xref: /openbmc/linux/drivers/dma/ppc4xx/adma.c (revision 8fdff1dc)
1 /*
2  * Copyright (C) 2006-2009 DENX Software Engineering.
3  *
4  * Author: Yuri Tikhonov <yur@emcraft.com>
5  *
6  * Further porting to arch/powerpc by
7  * 	Anatolij Gustschin <agust@denx.de>
8  *
9  * This program is free software; you can redistribute it and/or modify it
10  * under the terms of the GNU General Public License as published by the Free
11  * Software Foundation; either version 2 of the License, or (at your option)
12  * any later version.
13  *
14  * This program is distributed in the hope that it will be useful, but WITHOUT
15  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
16  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
17  * more details.
18  *
19  * You should have received a copy of the GNU General Public License along with
20  * this program; if not, write to the Free Software Foundation, Inc., 59
21  * Temple Place - Suite 330, Boston, MA  02111-1307, USA.
22  *
23  * The full GNU General Public License is included in this distribution in the
24  * file called COPYING.
25  */
26 
27 /*
28  * This driver supports the asynchrounous DMA copy and RAID engines available
29  * on the AMCC PPC440SPe Processors.
30  * Based on the Intel Xscale(R) family of I/O Processors (IOP 32x, 33x, 134x)
31  * ADMA driver written by D.Williams.
32  */
33 
34 #include <linux/init.h>
35 #include <linux/module.h>
36 #include <linux/async_tx.h>
37 #include <linux/delay.h>
38 #include <linux/dma-mapping.h>
39 #include <linux/spinlock.h>
40 #include <linux/interrupt.h>
41 #include <linux/slab.h>
42 #include <linux/uaccess.h>
43 #include <linux/proc_fs.h>
44 #include <linux/of.h>
45 #include <linux/of_platform.h>
46 #include <asm/dcr.h>
47 #include <asm/dcr-regs.h>
48 #include "adma.h"
49 #include "../dmaengine.h"
50 
51 enum ppc_adma_init_code {
52 	PPC_ADMA_INIT_OK = 0,
53 	PPC_ADMA_INIT_MEMRES,
54 	PPC_ADMA_INIT_MEMREG,
55 	PPC_ADMA_INIT_ALLOC,
56 	PPC_ADMA_INIT_COHERENT,
57 	PPC_ADMA_INIT_CHANNEL,
58 	PPC_ADMA_INIT_IRQ1,
59 	PPC_ADMA_INIT_IRQ2,
60 	PPC_ADMA_INIT_REGISTER
61 };
62 
63 static char *ppc_adma_errors[] = {
64 	[PPC_ADMA_INIT_OK] = "ok",
65 	[PPC_ADMA_INIT_MEMRES] = "failed to get memory resource",
66 	[PPC_ADMA_INIT_MEMREG] = "failed to request memory region",
67 	[PPC_ADMA_INIT_ALLOC] = "failed to allocate memory for adev "
68 				"structure",
69 	[PPC_ADMA_INIT_COHERENT] = "failed to allocate coherent memory for "
70 				   "hardware descriptors",
71 	[PPC_ADMA_INIT_CHANNEL] = "failed to allocate memory for channel",
72 	[PPC_ADMA_INIT_IRQ1] = "failed to request first irq",
73 	[PPC_ADMA_INIT_IRQ2] = "failed to request second irq",
74 	[PPC_ADMA_INIT_REGISTER] = "failed to register dma async device",
75 };
76 
77 static enum ppc_adma_init_code
78 ppc440spe_adma_devices[PPC440SPE_ADMA_ENGINES_NUM];
79 
80 struct ppc_dma_chan_ref {
81 	struct dma_chan *chan;
82 	struct list_head node;
83 };
84 
85 /* The list of channels exported by ppc440spe ADMA */
86 struct list_head
87 ppc440spe_adma_chan_list = LIST_HEAD_INIT(ppc440spe_adma_chan_list);
88 
89 /* This flag is set when want to refetch the xor chain in the interrupt
90  * handler
91  */
92 static u32 do_xor_refetch;
93 
94 /* Pointer to DMA0, DMA1 CP/CS FIFO */
95 static void *ppc440spe_dma_fifo_buf;
96 
97 /* Pointers to last submitted to DMA0, DMA1 CDBs */
98 static struct ppc440spe_adma_desc_slot *chan_last_sub[3];
99 static struct ppc440spe_adma_desc_slot *chan_first_cdb[3];
100 
101 /* Pointer to last linked and submitted xor CB */
102 static struct ppc440spe_adma_desc_slot *xor_last_linked;
103 static struct ppc440spe_adma_desc_slot *xor_last_submit;
104 
105 /* This array is used in data-check operations for storing a pattern */
106 static char ppc440spe_qword[16];
107 
108 static atomic_t ppc440spe_adma_err_irq_ref;
109 static dcr_host_t ppc440spe_mq_dcr_host;
110 static unsigned int ppc440spe_mq_dcr_len;
111 
112 /* Since RXOR operations use the common register (MQ0_CF2H) for setting-up
113  * the block size in transactions, then we do not allow to activate more than
114  * only one RXOR transactions simultaneously. So use this var to store
115  * the information about is RXOR currently active (PPC440SPE_RXOR_RUN bit is
116  * set) or not (PPC440SPE_RXOR_RUN is clear).
117  */
118 static unsigned long ppc440spe_rxor_state;
119 
120 /* These are used in enable & check routines
121  */
122 static u32 ppc440spe_r6_enabled;
123 static struct ppc440spe_adma_chan *ppc440spe_r6_tchan;
124 static struct completion ppc440spe_r6_test_comp;
125 
126 static int ppc440spe_adma_dma2rxor_prep_src(
127 		struct ppc440spe_adma_desc_slot *desc,
128 		struct ppc440spe_rxor *cursor, int index,
129 		int src_cnt, u32 addr);
130 static void ppc440spe_adma_dma2rxor_set_src(
131 		struct ppc440spe_adma_desc_slot *desc,
132 		int index, dma_addr_t addr);
133 static void ppc440spe_adma_dma2rxor_set_mult(
134 		struct ppc440spe_adma_desc_slot *desc,
135 		int index, u8 mult);
136 
137 #ifdef ADMA_LL_DEBUG
138 #define ADMA_LL_DBG(x) ({ if (1) x; 0; })
139 #else
140 #define ADMA_LL_DBG(x) ({ if (0) x; 0; })
141 #endif
142 
143 static void print_cb(struct ppc440spe_adma_chan *chan, void *block)
144 {
145 	struct dma_cdb *cdb;
146 	struct xor_cb *cb;
147 	int i;
148 
149 	switch (chan->device->id) {
150 	case 0:
151 	case 1:
152 		cdb = block;
153 
154 		pr_debug("CDB at %p [%d]:\n"
155 			"\t attr 0x%02x opc 0x%02x cnt 0x%08x\n"
156 			"\t sg1u 0x%08x sg1l 0x%08x\n"
157 			"\t sg2u 0x%08x sg2l 0x%08x\n"
158 			"\t sg3u 0x%08x sg3l 0x%08x\n",
159 			cdb, chan->device->id,
160 			cdb->attr, cdb->opc, le32_to_cpu(cdb->cnt),
161 			le32_to_cpu(cdb->sg1u), le32_to_cpu(cdb->sg1l),
162 			le32_to_cpu(cdb->sg2u), le32_to_cpu(cdb->sg2l),
163 			le32_to_cpu(cdb->sg3u), le32_to_cpu(cdb->sg3l)
164 		);
165 		break;
166 	case 2:
167 		cb = block;
168 
169 		pr_debug("CB at %p [%d]:\n"
170 			"\t cbc 0x%08x cbbc 0x%08x cbs 0x%08x\n"
171 			"\t cbtah 0x%08x cbtal 0x%08x\n"
172 			"\t cblah 0x%08x cblal 0x%08x\n",
173 			cb, chan->device->id,
174 			cb->cbc, cb->cbbc, cb->cbs,
175 			cb->cbtah, cb->cbtal,
176 			cb->cblah, cb->cblal);
177 		for (i = 0; i < 16; i++) {
178 			if (i && !cb->ops[i].h && !cb->ops[i].l)
179 				continue;
180 			pr_debug("\t ops[%2d]: h 0x%08x l 0x%08x\n",
181 				i, cb->ops[i].h, cb->ops[i].l);
182 		}
183 		break;
184 	}
185 }
186 
187 static void print_cb_list(struct ppc440spe_adma_chan *chan,
188 			  struct ppc440spe_adma_desc_slot *iter)
189 {
190 	for (; iter; iter = iter->hw_next)
191 		print_cb(chan, iter->hw_desc);
192 }
193 
194 static void prep_dma_xor_dbg(int id, dma_addr_t dst, dma_addr_t *src,
195 			     unsigned int src_cnt)
196 {
197 	int i;
198 
199 	pr_debug("\n%s(%d):\nsrc: ", __func__, id);
200 	for (i = 0; i < src_cnt; i++)
201 		pr_debug("\t0x%016llx ", src[i]);
202 	pr_debug("dst:\n\t0x%016llx\n", dst);
203 }
204 
205 static void prep_dma_pq_dbg(int id, dma_addr_t *dst, dma_addr_t *src,
206 			    unsigned int src_cnt)
207 {
208 	int i;
209 
210 	pr_debug("\n%s(%d):\nsrc: ", __func__, id);
211 	for (i = 0; i < src_cnt; i++)
212 		pr_debug("\t0x%016llx ", src[i]);
213 	pr_debug("dst: ");
214 	for (i = 0; i < 2; i++)
215 		pr_debug("\t0x%016llx ", dst[i]);
216 }
217 
218 static void prep_dma_pqzero_sum_dbg(int id, dma_addr_t *src,
219 				    unsigned int src_cnt,
220 				    const unsigned char *scf)
221 {
222 	int i;
223 
224 	pr_debug("\n%s(%d):\nsrc(coef): ", __func__, id);
225 	if (scf) {
226 		for (i = 0; i < src_cnt; i++)
227 			pr_debug("\t0x%016llx(0x%02x) ", src[i], scf[i]);
228 	} else {
229 		for (i = 0; i < src_cnt; i++)
230 			pr_debug("\t0x%016llx(no) ", src[i]);
231 	}
232 
233 	pr_debug("dst: ");
234 	for (i = 0; i < 2; i++)
235 		pr_debug("\t0x%016llx ", src[src_cnt + i]);
236 }
237 
238 /******************************************************************************
239  * Command (Descriptor) Blocks low-level routines
240  ******************************************************************************/
241 /**
242  * ppc440spe_desc_init_interrupt - initialize the descriptor for INTERRUPT
243  * pseudo operation
244  */
245 static void ppc440spe_desc_init_interrupt(struct ppc440spe_adma_desc_slot *desc,
246 					  struct ppc440spe_adma_chan *chan)
247 {
248 	struct xor_cb *p;
249 
250 	switch (chan->device->id) {
251 	case PPC440SPE_XOR_ID:
252 		p = desc->hw_desc;
253 		memset(desc->hw_desc, 0, sizeof(struct xor_cb));
254 		/* NOP with Command Block Complete Enable */
255 		p->cbc = XOR_CBCR_CBCE_BIT;
256 		break;
257 	case PPC440SPE_DMA0_ID:
258 	case PPC440SPE_DMA1_ID:
259 		memset(desc->hw_desc, 0, sizeof(struct dma_cdb));
260 		/* NOP with interrupt */
261 		set_bit(PPC440SPE_DESC_INT, &desc->flags);
262 		break;
263 	default:
264 		printk(KERN_ERR "Unsupported id %d in %s\n", chan->device->id,
265 				__func__);
266 		break;
267 	}
268 }
269 
270 /**
271  * ppc440spe_desc_init_null_xor - initialize the descriptor for NULL XOR
272  * pseudo operation
273  */
274 static void ppc440spe_desc_init_null_xor(struct ppc440spe_adma_desc_slot *desc)
275 {
276 	memset(desc->hw_desc, 0, sizeof(struct xor_cb));
277 	desc->hw_next = NULL;
278 	desc->src_cnt = 0;
279 	desc->dst_cnt = 1;
280 }
281 
282 /**
283  * ppc440spe_desc_init_xor - initialize the descriptor for XOR operation
284  */
285 static void ppc440spe_desc_init_xor(struct ppc440spe_adma_desc_slot *desc,
286 					 int src_cnt, unsigned long flags)
287 {
288 	struct xor_cb *hw_desc = desc->hw_desc;
289 
290 	memset(desc->hw_desc, 0, sizeof(struct xor_cb));
291 	desc->hw_next = NULL;
292 	desc->src_cnt = src_cnt;
293 	desc->dst_cnt = 1;
294 
295 	hw_desc->cbc = XOR_CBCR_TGT_BIT | src_cnt;
296 	if (flags & DMA_PREP_INTERRUPT)
297 		/* Enable interrupt on completion */
298 		hw_desc->cbc |= XOR_CBCR_CBCE_BIT;
299 }
300 
301 /**
302  * ppc440spe_desc_init_dma2pq - initialize the descriptor for PQ
303  * operation in DMA2 controller
304  */
305 static void ppc440spe_desc_init_dma2pq(struct ppc440spe_adma_desc_slot *desc,
306 		int dst_cnt, int src_cnt, unsigned long flags)
307 {
308 	struct xor_cb *hw_desc = desc->hw_desc;
309 
310 	memset(desc->hw_desc, 0, sizeof(struct xor_cb));
311 	desc->hw_next = NULL;
312 	desc->src_cnt = src_cnt;
313 	desc->dst_cnt = dst_cnt;
314 	memset(desc->reverse_flags, 0, sizeof(desc->reverse_flags));
315 	desc->descs_per_op = 0;
316 
317 	hw_desc->cbc = XOR_CBCR_TGT_BIT;
318 	if (flags & DMA_PREP_INTERRUPT)
319 		/* Enable interrupt on completion */
320 		hw_desc->cbc |= XOR_CBCR_CBCE_BIT;
321 }
322 
323 #define DMA_CTRL_FLAGS_LAST	DMA_PREP_FENCE
324 #define DMA_PREP_ZERO_P		(DMA_CTRL_FLAGS_LAST << 1)
325 #define DMA_PREP_ZERO_Q		(DMA_PREP_ZERO_P << 1)
326 
327 /**
328  * ppc440spe_desc_init_dma01pq - initialize the descriptors for PQ operation
329  * with DMA0/1
330  */
331 static void ppc440spe_desc_init_dma01pq(struct ppc440spe_adma_desc_slot *desc,
332 				int dst_cnt, int src_cnt, unsigned long flags,
333 				unsigned long op)
334 {
335 	struct dma_cdb *hw_desc;
336 	struct ppc440spe_adma_desc_slot *iter;
337 	u8 dopc;
338 
339 	/* Common initialization of a PQ descriptors chain */
340 	set_bits(op, &desc->flags);
341 	desc->src_cnt = src_cnt;
342 	desc->dst_cnt = dst_cnt;
343 
344 	/* WXOR MULTICAST if both P and Q are being computed
345 	 * MV_SG1_SG2 if Q only
346 	 */
347 	dopc = (desc->dst_cnt == DMA_DEST_MAX_NUM) ?
348 		DMA_CDB_OPC_MULTICAST : DMA_CDB_OPC_MV_SG1_SG2;
349 
350 	list_for_each_entry(iter, &desc->group_list, chain_node) {
351 		hw_desc = iter->hw_desc;
352 		memset(iter->hw_desc, 0, sizeof(struct dma_cdb));
353 
354 		if (likely(!list_is_last(&iter->chain_node,
355 				&desc->group_list))) {
356 			/* set 'next' pointer */
357 			iter->hw_next = list_entry(iter->chain_node.next,
358 				struct ppc440spe_adma_desc_slot, chain_node);
359 			clear_bit(PPC440SPE_DESC_INT, &iter->flags);
360 		} else {
361 			/* this is the last descriptor.
362 			 * this slot will be pasted from ADMA level
363 			 * each time it wants to configure parameters
364 			 * of the transaction (src, dst, ...)
365 			 */
366 			iter->hw_next = NULL;
367 			if (flags & DMA_PREP_INTERRUPT)
368 				set_bit(PPC440SPE_DESC_INT, &iter->flags);
369 			else
370 				clear_bit(PPC440SPE_DESC_INT, &iter->flags);
371 		}
372 	}
373 
374 	/* Set OPS depending on WXOR/RXOR type of operation */
375 	if (!test_bit(PPC440SPE_DESC_RXOR, &desc->flags)) {
376 		/* This is a WXOR only chain:
377 		 * - first descriptors are for zeroing destinations
378 		 *   if PPC440SPE_ZERO_P/Q set;
379 		 * - descriptors remained are for GF-XOR operations.
380 		 */
381 		iter = list_first_entry(&desc->group_list,
382 					struct ppc440spe_adma_desc_slot,
383 					chain_node);
384 
385 		if (test_bit(PPC440SPE_ZERO_P, &desc->flags)) {
386 			hw_desc = iter->hw_desc;
387 			hw_desc->opc = DMA_CDB_OPC_MV_SG1_SG2;
388 			iter = list_first_entry(&iter->chain_node,
389 					struct ppc440spe_adma_desc_slot,
390 					chain_node);
391 		}
392 
393 		if (test_bit(PPC440SPE_ZERO_Q, &desc->flags)) {
394 			hw_desc = iter->hw_desc;
395 			hw_desc->opc = DMA_CDB_OPC_MV_SG1_SG2;
396 			iter = list_first_entry(&iter->chain_node,
397 					struct ppc440spe_adma_desc_slot,
398 					chain_node);
399 		}
400 
401 		list_for_each_entry_from(iter, &desc->group_list, chain_node) {
402 			hw_desc = iter->hw_desc;
403 			hw_desc->opc = dopc;
404 		}
405 	} else {
406 		/* This is either RXOR-only or mixed RXOR/WXOR */
407 
408 		/* The first 1 or 2 slots in chain are always RXOR,
409 		 * if need to calculate P & Q, then there are two
410 		 * RXOR slots; if only P or only Q, then there is one
411 		 */
412 		iter = list_first_entry(&desc->group_list,
413 					struct ppc440spe_adma_desc_slot,
414 					chain_node);
415 		hw_desc = iter->hw_desc;
416 		hw_desc->opc = DMA_CDB_OPC_MV_SG1_SG2;
417 
418 		if (desc->dst_cnt == DMA_DEST_MAX_NUM) {
419 			iter = list_first_entry(&iter->chain_node,
420 						struct ppc440spe_adma_desc_slot,
421 						chain_node);
422 			hw_desc = iter->hw_desc;
423 			hw_desc->opc = DMA_CDB_OPC_MV_SG1_SG2;
424 		}
425 
426 		/* The remaining descs (if any) are WXORs */
427 		if (test_bit(PPC440SPE_DESC_WXOR, &desc->flags)) {
428 			iter = list_first_entry(&iter->chain_node,
429 						struct ppc440spe_adma_desc_slot,
430 						chain_node);
431 			list_for_each_entry_from(iter, &desc->group_list,
432 						chain_node) {
433 				hw_desc = iter->hw_desc;
434 				hw_desc->opc = dopc;
435 			}
436 		}
437 	}
438 }
439 
440 /**
441  * ppc440spe_desc_init_dma01pqzero_sum - initialize the descriptor
442  * for PQ_ZERO_SUM operation
443  */
444 static void ppc440spe_desc_init_dma01pqzero_sum(
445 				struct ppc440spe_adma_desc_slot *desc,
446 				int dst_cnt, int src_cnt)
447 {
448 	struct dma_cdb *hw_desc;
449 	struct ppc440spe_adma_desc_slot *iter;
450 	int i = 0;
451 	u8 dopc = (dst_cnt == 2) ? DMA_CDB_OPC_MULTICAST :
452 				   DMA_CDB_OPC_MV_SG1_SG2;
453 	/*
454 	 * Initialize starting from 2nd or 3rd descriptor dependent
455 	 * on dst_cnt. First one or two slots are for cloning P
456 	 * and/or Q to chan->pdest and/or chan->qdest as we have
457 	 * to preserve original P/Q.
458 	 */
459 	iter = list_first_entry(&desc->group_list,
460 				struct ppc440spe_adma_desc_slot, chain_node);
461 	iter = list_entry(iter->chain_node.next,
462 			  struct ppc440spe_adma_desc_slot, chain_node);
463 
464 	if (dst_cnt > 1) {
465 		iter = list_entry(iter->chain_node.next,
466 				  struct ppc440spe_adma_desc_slot, chain_node);
467 	}
468 	/* initialize each source descriptor in chain */
469 	list_for_each_entry_from(iter, &desc->group_list, chain_node) {
470 		hw_desc = iter->hw_desc;
471 		memset(iter->hw_desc, 0, sizeof(struct dma_cdb));
472 		iter->src_cnt = 0;
473 		iter->dst_cnt = 0;
474 
475 		/* This is a ZERO_SUM operation:
476 		 * - <src_cnt> descriptors starting from 2nd or 3rd
477 		 *   descriptor are for GF-XOR operations;
478 		 * - remaining <dst_cnt> descriptors are for checking the result
479 		 */
480 		if (i++ < src_cnt)
481 			/* MV_SG1_SG2 if only Q is being verified
482 			 * MULTICAST if both P and Q are being verified
483 			 */
484 			hw_desc->opc = dopc;
485 		else
486 			/* DMA_CDB_OPC_DCHECK128 operation */
487 			hw_desc->opc = DMA_CDB_OPC_DCHECK128;
488 
489 		if (likely(!list_is_last(&iter->chain_node,
490 					 &desc->group_list))) {
491 			/* set 'next' pointer */
492 			iter->hw_next = list_entry(iter->chain_node.next,
493 						struct ppc440spe_adma_desc_slot,
494 						chain_node);
495 		} else {
496 			/* this is the last descriptor.
497 			 * this slot will be pasted from ADMA level
498 			 * each time it wants to configure parameters
499 			 * of the transaction (src, dst, ...)
500 			 */
501 			iter->hw_next = NULL;
502 			/* always enable interrupt generation since we get
503 			 * the status of pqzero from the handler
504 			 */
505 			set_bit(PPC440SPE_DESC_INT, &iter->flags);
506 		}
507 	}
508 	desc->src_cnt = src_cnt;
509 	desc->dst_cnt = dst_cnt;
510 }
511 
512 /**
513  * ppc440spe_desc_init_memcpy - initialize the descriptor for MEMCPY operation
514  */
515 static void ppc440spe_desc_init_memcpy(struct ppc440spe_adma_desc_slot *desc,
516 					unsigned long flags)
517 {
518 	struct dma_cdb *hw_desc = desc->hw_desc;
519 
520 	memset(desc->hw_desc, 0, sizeof(struct dma_cdb));
521 	desc->hw_next = NULL;
522 	desc->src_cnt = 1;
523 	desc->dst_cnt = 1;
524 
525 	if (flags & DMA_PREP_INTERRUPT)
526 		set_bit(PPC440SPE_DESC_INT, &desc->flags);
527 	else
528 		clear_bit(PPC440SPE_DESC_INT, &desc->flags);
529 
530 	hw_desc->opc = DMA_CDB_OPC_MV_SG1_SG2;
531 }
532 
533 /**
534  * ppc440spe_desc_init_memset - initialize the descriptor for MEMSET operation
535  */
536 static void ppc440spe_desc_init_memset(struct ppc440spe_adma_desc_slot *desc,
537 					int value, unsigned long flags)
538 {
539 	struct dma_cdb *hw_desc = desc->hw_desc;
540 
541 	memset(desc->hw_desc, 0, sizeof(struct dma_cdb));
542 	desc->hw_next = NULL;
543 	desc->src_cnt = 1;
544 	desc->dst_cnt = 1;
545 
546 	if (flags & DMA_PREP_INTERRUPT)
547 		set_bit(PPC440SPE_DESC_INT, &desc->flags);
548 	else
549 		clear_bit(PPC440SPE_DESC_INT, &desc->flags);
550 
551 	hw_desc->sg1u = hw_desc->sg1l = cpu_to_le32((u32)value);
552 	hw_desc->sg3u = hw_desc->sg3l = cpu_to_le32((u32)value);
553 	hw_desc->opc = DMA_CDB_OPC_DFILL128;
554 }
555 
556 /**
557  * ppc440spe_desc_set_src_addr - set source address into the descriptor
558  */
559 static void ppc440spe_desc_set_src_addr(struct ppc440spe_adma_desc_slot *desc,
560 					struct ppc440spe_adma_chan *chan,
561 					int src_idx, dma_addr_t addrh,
562 					dma_addr_t addrl)
563 {
564 	struct dma_cdb *dma_hw_desc;
565 	struct xor_cb *xor_hw_desc;
566 	phys_addr_t addr64, tmplow, tmphi;
567 
568 	switch (chan->device->id) {
569 	case PPC440SPE_DMA0_ID:
570 	case PPC440SPE_DMA1_ID:
571 		if (!addrh) {
572 			addr64 = addrl;
573 			tmphi = (addr64 >> 32);
574 			tmplow = (addr64 & 0xFFFFFFFF);
575 		} else {
576 			tmphi = addrh;
577 			tmplow = addrl;
578 		}
579 		dma_hw_desc = desc->hw_desc;
580 		dma_hw_desc->sg1l = cpu_to_le32((u32)tmplow);
581 		dma_hw_desc->sg1u |= cpu_to_le32((u32)tmphi);
582 		break;
583 	case PPC440SPE_XOR_ID:
584 		xor_hw_desc = desc->hw_desc;
585 		xor_hw_desc->ops[src_idx].l = addrl;
586 		xor_hw_desc->ops[src_idx].h |= addrh;
587 		break;
588 	}
589 }
590 
591 /**
592  * ppc440spe_desc_set_src_mult - set source address mult into the descriptor
593  */
594 static void ppc440spe_desc_set_src_mult(struct ppc440spe_adma_desc_slot *desc,
595 			struct ppc440spe_adma_chan *chan, u32 mult_index,
596 			int sg_index, unsigned char mult_value)
597 {
598 	struct dma_cdb *dma_hw_desc;
599 	struct xor_cb *xor_hw_desc;
600 	u32 *psgu;
601 
602 	switch (chan->device->id) {
603 	case PPC440SPE_DMA0_ID:
604 	case PPC440SPE_DMA1_ID:
605 		dma_hw_desc = desc->hw_desc;
606 
607 		switch (sg_index) {
608 		/* for RXOR operations set multiplier
609 		 * into source cued address
610 		 */
611 		case DMA_CDB_SG_SRC:
612 			psgu = &dma_hw_desc->sg1u;
613 			break;
614 		/* for WXOR operations set multiplier
615 		 * into destination cued address(es)
616 		 */
617 		case DMA_CDB_SG_DST1:
618 			psgu = &dma_hw_desc->sg2u;
619 			break;
620 		case DMA_CDB_SG_DST2:
621 			psgu = &dma_hw_desc->sg3u;
622 			break;
623 		default:
624 			BUG();
625 		}
626 
627 		*psgu |= cpu_to_le32(mult_value << mult_index);
628 		break;
629 	case PPC440SPE_XOR_ID:
630 		xor_hw_desc = desc->hw_desc;
631 		break;
632 	default:
633 		BUG();
634 	}
635 }
636 
637 /**
638  * ppc440spe_desc_set_dest_addr - set destination address into the descriptor
639  */
640 static void ppc440spe_desc_set_dest_addr(struct ppc440spe_adma_desc_slot *desc,
641 				struct ppc440spe_adma_chan *chan,
642 				dma_addr_t addrh, dma_addr_t addrl,
643 				u32 dst_idx)
644 {
645 	struct dma_cdb *dma_hw_desc;
646 	struct xor_cb *xor_hw_desc;
647 	phys_addr_t addr64, tmphi, tmplow;
648 	u32 *psgu, *psgl;
649 
650 	switch (chan->device->id) {
651 	case PPC440SPE_DMA0_ID:
652 	case PPC440SPE_DMA1_ID:
653 		if (!addrh) {
654 			addr64 = addrl;
655 			tmphi = (addr64 >> 32);
656 			tmplow = (addr64 & 0xFFFFFFFF);
657 		} else {
658 			tmphi = addrh;
659 			tmplow = addrl;
660 		}
661 		dma_hw_desc = desc->hw_desc;
662 
663 		psgu = dst_idx ? &dma_hw_desc->sg3u : &dma_hw_desc->sg2u;
664 		psgl = dst_idx ? &dma_hw_desc->sg3l : &dma_hw_desc->sg2l;
665 
666 		*psgl = cpu_to_le32((u32)tmplow);
667 		*psgu |= cpu_to_le32((u32)tmphi);
668 		break;
669 	case PPC440SPE_XOR_ID:
670 		xor_hw_desc = desc->hw_desc;
671 		xor_hw_desc->cbtal = addrl;
672 		xor_hw_desc->cbtah |= addrh;
673 		break;
674 	}
675 }
676 
677 /**
678  * ppc440spe_desc_set_byte_count - set number of data bytes involved
679  * into the operation
680  */
681 static void ppc440spe_desc_set_byte_count(struct ppc440spe_adma_desc_slot *desc,
682 				struct ppc440spe_adma_chan *chan,
683 				u32 byte_count)
684 {
685 	struct dma_cdb *dma_hw_desc;
686 	struct xor_cb *xor_hw_desc;
687 
688 	switch (chan->device->id) {
689 	case PPC440SPE_DMA0_ID:
690 	case PPC440SPE_DMA1_ID:
691 		dma_hw_desc = desc->hw_desc;
692 		dma_hw_desc->cnt = cpu_to_le32(byte_count);
693 		break;
694 	case PPC440SPE_XOR_ID:
695 		xor_hw_desc = desc->hw_desc;
696 		xor_hw_desc->cbbc = byte_count;
697 		break;
698 	}
699 }
700 
701 /**
702  * ppc440spe_desc_set_rxor_block_size - set RXOR block size
703  */
704 static inline void ppc440spe_desc_set_rxor_block_size(u32 byte_count)
705 {
706 	/* assume that byte_count is aligned on the 512-boundary;
707 	 * thus write it directly to the register (bits 23:31 are
708 	 * reserved there).
709 	 */
710 	dcr_write(ppc440spe_mq_dcr_host, DCRN_MQ0_CF2H, byte_count);
711 }
712 
713 /**
714  * ppc440spe_desc_set_dcheck - set CHECK pattern
715  */
716 static void ppc440spe_desc_set_dcheck(struct ppc440spe_adma_desc_slot *desc,
717 				struct ppc440spe_adma_chan *chan, u8 *qword)
718 {
719 	struct dma_cdb *dma_hw_desc;
720 
721 	switch (chan->device->id) {
722 	case PPC440SPE_DMA0_ID:
723 	case PPC440SPE_DMA1_ID:
724 		dma_hw_desc = desc->hw_desc;
725 		iowrite32(qword[0], &dma_hw_desc->sg3l);
726 		iowrite32(qword[4], &dma_hw_desc->sg3u);
727 		iowrite32(qword[8], &dma_hw_desc->sg2l);
728 		iowrite32(qword[12], &dma_hw_desc->sg2u);
729 		break;
730 	default:
731 		BUG();
732 	}
733 }
734 
735 /**
736  * ppc440spe_xor_set_link - set link address in xor CB
737  */
738 static void ppc440spe_xor_set_link(struct ppc440spe_adma_desc_slot *prev_desc,
739 				struct ppc440spe_adma_desc_slot *next_desc)
740 {
741 	struct xor_cb *xor_hw_desc = prev_desc->hw_desc;
742 
743 	if (unlikely(!next_desc || !(next_desc->phys))) {
744 		printk(KERN_ERR "%s: next_desc=0x%p; next_desc->phys=0x%llx\n",
745 			__func__, next_desc,
746 			next_desc ? next_desc->phys : 0);
747 		BUG();
748 	}
749 
750 	xor_hw_desc->cbs = 0;
751 	xor_hw_desc->cblal = next_desc->phys;
752 	xor_hw_desc->cblah = 0;
753 	xor_hw_desc->cbc |= XOR_CBCR_LNK_BIT;
754 }
755 
756 /**
757  * ppc440spe_desc_set_link - set the address of descriptor following this
758  * descriptor in chain
759  */
760 static void ppc440spe_desc_set_link(struct ppc440spe_adma_chan *chan,
761 				struct ppc440spe_adma_desc_slot *prev_desc,
762 				struct ppc440spe_adma_desc_slot *next_desc)
763 {
764 	unsigned long flags;
765 	struct ppc440spe_adma_desc_slot *tail = next_desc;
766 
767 	if (unlikely(!prev_desc || !next_desc ||
768 		(prev_desc->hw_next && prev_desc->hw_next != next_desc))) {
769 		/* If previous next is overwritten something is wrong.
770 		 * though we may refetch from append to initiate list
771 		 * processing; in this case - it's ok.
772 		 */
773 		printk(KERN_ERR "%s: prev_desc=0x%p; next_desc=0x%p; "
774 			"prev->hw_next=0x%p\n", __func__, prev_desc,
775 			next_desc, prev_desc ? prev_desc->hw_next : 0);
776 		BUG();
777 	}
778 
779 	local_irq_save(flags);
780 
781 	/* do s/w chaining both for DMA and XOR descriptors */
782 	prev_desc->hw_next = next_desc;
783 
784 	switch (chan->device->id) {
785 	case PPC440SPE_DMA0_ID:
786 	case PPC440SPE_DMA1_ID:
787 		break;
788 	case PPC440SPE_XOR_ID:
789 		/* bind descriptor to the chain */
790 		while (tail->hw_next)
791 			tail = tail->hw_next;
792 		xor_last_linked = tail;
793 
794 		if (prev_desc == xor_last_submit)
795 			/* do not link to the last submitted CB */
796 			break;
797 		ppc440spe_xor_set_link(prev_desc, next_desc);
798 		break;
799 	}
800 
801 	local_irq_restore(flags);
802 }
803 
804 /**
805  * ppc440spe_desc_get_src_addr - extract the source address from the descriptor
806  */
807 static u32 ppc440spe_desc_get_src_addr(struct ppc440spe_adma_desc_slot *desc,
808 				struct ppc440spe_adma_chan *chan, int src_idx)
809 {
810 	struct dma_cdb *dma_hw_desc;
811 	struct xor_cb *xor_hw_desc;
812 
813 	switch (chan->device->id) {
814 	case PPC440SPE_DMA0_ID:
815 	case PPC440SPE_DMA1_ID:
816 		dma_hw_desc = desc->hw_desc;
817 		/* May have 0, 1, 2, or 3 sources */
818 		switch (dma_hw_desc->opc) {
819 		case DMA_CDB_OPC_NO_OP:
820 		case DMA_CDB_OPC_DFILL128:
821 			return 0;
822 		case DMA_CDB_OPC_DCHECK128:
823 			if (unlikely(src_idx)) {
824 				printk(KERN_ERR "%s: try to get %d source for"
825 				    " DCHECK128\n", __func__, src_idx);
826 				BUG();
827 			}
828 			return le32_to_cpu(dma_hw_desc->sg1l);
829 		case DMA_CDB_OPC_MULTICAST:
830 		case DMA_CDB_OPC_MV_SG1_SG2:
831 			if (unlikely(src_idx > 2)) {
832 				printk(KERN_ERR "%s: try to get %d source from"
833 				    " DMA descr\n", __func__, src_idx);
834 				BUG();
835 			}
836 			if (src_idx) {
837 				if (le32_to_cpu(dma_hw_desc->sg1u) &
838 				    DMA_CUED_XOR_WIN_MSK) {
839 					u8 region;
840 
841 					if (src_idx == 1)
842 						return le32_to_cpu(
843 						    dma_hw_desc->sg1l) +
844 							desc->unmap_len;
845 
846 					region = (le32_to_cpu(
847 					    dma_hw_desc->sg1u)) >>
848 						DMA_CUED_REGION_OFF;
849 
850 					region &= DMA_CUED_REGION_MSK;
851 					switch (region) {
852 					case DMA_RXOR123:
853 						return le32_to_cpu(
854 						    dma_hw_desc->sg1l) +
855 							(desc->unmap_len << 1);
856 					case DMA_RXOR124:
857 						return le32_to_cpu(
858 						    dma_hw_desc->sg1l) +
859 							(desc->unmap_len * 3);
860 					case DMA_RXOR125:
861 						return le32_to_cpu(
862 						    dma_hw_desc->sg1l) +
863 							(desc->unmap_len << 2);
864 					default:
865 						printk(KERN_ERR
866 						    "%s: try to"
867 						    " get src3 for region %02x"
868 						    "PPC440SPE_DESC_RXOR12?\n",
869 						    __func__, region);
870 						BUG();
871 					}
872 				} else {
873 					printk(KERN_ERR
874 						"%s: try to get %d"
875 						" source for non-cued descr\n",
876 						__func__, src_idx);
877 					BUG();
878 				}
879 			}
880 			return le32_to_cpu(dma_hw_desc->sg1l);
881 		default:
882 			printk(KERN_ERR "%s: unknown OPC 0x%02x\n",
883 				__func__, dma_hw_desc->opc);
884 			BUG();
885 		}
886 		return le32_to_cpu(dma_hw_desc->sg1l);
887 	case PPC440SPE_XOR_ID:
888 		/* May have up to 16 sources */
889 		xor_hw_desc = desc->hw_desc;
890 		return xor_hw_desc->ops[src_idx].l;
891 	}
892 	return 0;
893 }
894 
895 /**
896  * ppc440spe_desc_get_dest_addr - extract the destination address from the
897  * descriptor
898  */
899 static u32 ppc440spe_desc_get_dest_addr(struct ppc440spe_adma_desc_slot *desc,
900 				struct ppc440spe_adma_chan *chan, int idx)
901 {
902 	struct dma_cdb *dma_hw_desc;
903 	struct xor_cb *xor_hw_desc;
904 
905 	switch (chan->device->id) {
906 	case PPC440SPE_DMA0_ID:
907 	case PPC440SPE_DMA1_ID:
908 		dma_hw_desc = desc->hw_desc;
909 
910 		if (likely(!idx))
911 			return le32_to_cpu(dma_hw_desc->sg2l);
912 		return le32_to_cpu(dma_hw_desc->sg3l);
913 	case PPC440SPE_XOR_ID:
914 		xor_hw_desc = desc->hw_desc;
915 		return xor_hw_desc->cbtal;
916 	}
917 	return 0;
918 }
919 
920 /**
921  * ppc440spe_desc_get_src_num - extract the number of source addresses from
922  * the descriptor
923  */
924 static u32 ppc440spe_desc_get_src_num(struct ppc440spe_adma_desc_slot *desc,
925 				struct ppc440spe_adma_chan *chan)
926 {
927 	struct dma_cdb *dma_hw_desc;
928 	struct xor_cb *xor_hw_desc;
929 
930 	switch (chan->device->id) {
931 	case PPC440SPE_DMA0_ID:
932 	case PPC440SPE_DMA1_ID:
933 		dma_hw_desc = desc->hw_desc;
934 
935 		switch (dma_hw_desc->opc) {
936 		case DMA_CDB_OPC_NO_OP:
937 		case DMA_CDB_OPC_DFILL128:
938 			return 0;
939 		case DMA_CDB_OPC_DCHECK128:
940 			return 1;
941 		case DMA_CDB_OPC_MV_SG1_SG2:
942 		case DMA_CDB_OPC_MULTICAST:
943 			/*
944 			 * Only for RXOR operations we have more than
945 			 * one source
946 			 */
947 			if (le32_to_cpu(dma_hw_desc->sg1u) &
948 			    DMA_CUED_XOR_WIN_MSK) {
949 				/* RXOR op, there are 2 or 3 sources */
950 				if (((le32_to_cpu(dma_hw_desc->sg1u) >>
951 				    DMA_CUED_REGION_OFF) &
952 				      DMA_CUED_REGION_MSK) == DMA_RXOR12) {
953 					/* RXOR 1-2 */
954 					return 2;
955 				} else {
956 					/* RXOR 1-2-3/1-2-4/1-2-5 */
957 					return 3;
958 				}
959 			}
960 			return 1;
961 		default:
962 			printk(KERN_ERR "%s: unknown OPC 0x%02x\n",
963 				__func__, dma_hw_desc->opc);
964 			BUG();
965 		}
966 	case PPC440SPE_XOR_ID:
967 		/* up to 16 sources */
968 		xor_hw_desc = desc->hw_desc;
969 		return xor_hw_desc->cbc & XOR_CDCR_OAC_MSK;
970 	default:
971 		BUG();
972 	}
973 	return 0;
974 }
975 
976 /**
977  * ppc440spe_desc_get_dst_num - get the number of destination addresses in
978  * this descriptor
979  */
980 static u32 ppc440spe_desc_get_dst_num(struct ppc440spe_adma_desc_slot *desc,
981 				struct ppc440spe_adma_chan *chan)
982 {
983 	struct dma_cdb *dma_hw_desc;
984 
985 	switch (chan->device->id) {
986 	case PPC440SPE_DMA0_ID:
987 	case PPC440SPE_DMA1_ID:
988 		/* May be 1 or 2 destinations */
989 		dma_hw_desc = desc->hw_desc;
990 		switch (dma_hw_desc->opc) {
991 		case DMA_CDB_OPC_NO_OP:
992 		case DMA_CDB_OPC_DCHECK128:
993 			return 0;
994 		case DMA_CDB_OPC_MV_SG1_SG2:
995 		case DMA_CDB_OPC_DFILL128:
996 			return 1;
997 		case DMA_CDB_OPC_MULTICAST:
998 			if (desc->dst_cnt == 2)
999 				return 2;
1000 			else
1001 				return 1;
1002 		default:
1003 			printk(KERN_ERR "%s: unknown OPC 0x%02x\n",
1004 				__func__, dma_hw_desc->opc);
1005 			BUG();
1006 		}
1007 	case PPC440SPE_XOR_ID:
1008 		/* Always only 1 destination */
1009 		return 1;
1010 	default:
1011 		BUG();
1012 	}
1013 	return 0;
1014 }
1015 
1016 /**
1017  * ppc440spe_desc_get_link - get the address of the descriptor that
1018  * follows this one
1019  */
1020 static inline u32 ppc440spe_desc_get_link(struct ppc440spe_adma_desc_slot *desc,
1021 					struct ppc440spe_adma_chan *chan)
1022 {
1023 	if (!desc->hw_next)
1024 		return 0;
1025 
1026 	return desc->hw_next->phys;
1027 }
1028 
1029 /**
1030  * ppc440spe_desc_is_aligned - check alignment
1031  */
1032 static inline int ppc440spe_desc_is_aligned(
1033 	struct ppc440spe_adma_desc_slot *desc, int num_slots)
1034 {
1035 	return (desc->idx & (num_slots - 1)) ? 0 : 1;
1036 }
1037 
1038 /**
1039  * ppc440spe_chan_xor_slot_count - get the number of slots necessary for
1040  * XOR operation
1041  */
1042 static int ppc440spe_chan_xor_slot_count(size_t len, int src_cnt,
1043 			int *slots_per_op)
1044 {
1045 	int slot_cnt;
1046 
1047 	/* each XOR descriptor provides up to 16 source operands */
1048 	slot_cnt = *slots_per_op = (src_cnt + XOR_MAX_OPS - 1)/XOR_MAX_OPS;
1049 
1050 	if (likely(len <= PPC440SPE_ADMA_XOR_MAX_BYTE_COUNT))
1051 		return slot_cnt;
1052 
1053 	printk(KERN_ERR "%s: len %d > max %d !!\n",
1054 		__func__, len, PPC440SPE_ADMA_XOR_MAX_BYTE_COUNT);
1055 	BUG();
1056 	return slot_cnt;
1057 }
1058 
1059 /**
1060  * ppc440spe_dma2_pq_slot_count - get the number of slots necessary for
1061  * DMA2 PQ operation
1062  */
1063 static int ppc440spe_dma2_pq_slot_count(dma_addr_t *srcs,
1064 		int src_cnt, size_t len)
1065 {
1066 	signed long long order = 0;
1067 	int state = 0;
1068 	int addr_count = 0;
1069 	int i;
1070 	for (i = 1; i < src_cnt; i++) {
1071 		dma_addr_t cur_addr = srcs[i];
1072 		dma_addr_t old_addr = srcs[i-1];
1073 		switch (state) {
1074 		case 0:
1075 			if (cur_addr == old_addr + len) {
1076 				/* direct RXOR */
1077 				order = 1;
1078 				state = 1;
1079 				if (i == src_cnt-1)
1080 					addr_count++;
1081 			} else if (old_addr == cur_addr + len) {
1082 				/* reverse RXOR */
1083 				order = -1;
1084 				state = 1;
1085 				if (i == src_cnt-1)
1086 					addr_count++;
1087 			} else {
1088 				state = 3;
1089 			}
1090 			break;
1091 		case 1:
1092 			if (i == src_cnt-2 || (order == -1
1093 				&& cur_addr != old_addr - len)) {
1094 				order = 0;
1095 				state = 0;
1096 				addr_count++;
1097 			} else if (cur_addr == old_addr + len*order) {
1098 				state = 2;
1099 				if (i == src_cnt-1)
1100 					addr_count++;
1101 			} else if (cur_addr == old_addr + 2*len) {
1102 				state = 2;
1103 				if (i == src_cnt-1)
1104 					addr_count++;
1105 			} else if (cur_addr == old_addr + 3*len) {
1106 				state = 2;
1107 				if (i == src_cnt-1)
1108 					addr_count++;
1109 			} else {
1110 				order = 0;
1111 				state = 0;
1112 				addr_count++;
1113 			}
1114 			break;
1115 		case 2:
1116 			order = 0;
1117 			state = 0;
1118 			addr_count++;
1119 				break;
1120 		}
1121 		if (state == 3)
1122 			break;
1123 	}
1124 	if (src_cnt <= 1 || (state != 1 && state != 2)) {
1125 		pr_err("%s: src_cnt=%d, state=%d, addr_count=%d, order=%lld\n",
1126 			__func__, src_cnt, state, addr_count, order);
1127 		for (i = 0; i < src_cnt; i++)
1128 			pr_err("\t[%d] 0x%llx \n", i, srcs[i]);
1129 		BUG();
1130 	}
1131 
1132 	return (addr_count + XOR_MAX_OPS - 1) / XOR_MAX_OPS;
1133 }
1134 
1135 
1136 /******************************************************************************
1137  * ADMA channel low-level routines
1138  ******************************************************************************/
1139 
1140 static u32
1141 ppc440spe_chan_get_current_descriptor(struct ppc440spe_adma_chan *chan);
1142 static void ppc440spe_chan_append(struct ppc440spe_adma_chan *chan);
1143 
1144 /**
1145  * ppc440spe_adma_device_clear_eot_status - interrupt ack to XOR or DMA engine
1146  */
1147 static void ppc440spe_adma_device_clear_eot_status(
1148 					struct ppc440spe_adma_chan *chan)
1149 {
1150 	struct dma_regs *dma_reg;
1151 	struct xor_regs *xor_reg;
1152 	u8 *p = chan->device->dma_desc_pool_virt;
1153 	struct dma_cdb *cdb;
1154 	u32 rv, i;
1155 
1156 	switch (chan->device->id) {
1157 	case PPC440SPE_DMA0_ID:
1158 	case PPC440SPE_DMA1_ID:
1159 		/* read FIFO to ack */
1160 		dma_reg = chan->device->dma_reg;
1161 		while ((rv = ioread32(&dma_reg->csfpl))) {
1162 			i = rv & DMA_CDB_ADDR_MSK;
1163 			cdb = (struct dma_cdb *)&p[i -
1164 			    (u32)chan->device->dma_desc_pool];
1165 
1166 			/* Clear opcode to ack. This is necessary for
1167 			 * ZeroSum operations only
1168 			 */
1169 			cdb->opc = 0;
1170 
1171 			if (test_bit(PPC440SPE_RXOR_RUN,
1172 			    &ppc440spe_rxor_state)) {
1173 				/* probably this is a completed RXOR op,
1174 				 * get pointer to CDB using the fact that
1175 				 * physical and virtual addresses of CDB
1176 				 * in pools have the same offsets
1177 				 */
1178 				if (le32_to_cpu(cdb->sg1u) &
1179 				    DMA_CUED_XOR_BASE) {
1180 					/* this is a RXOR */
1181 					clear_bit(PPC440SPE_RXOR_RUN,
1182 						  &ppc440spe_rxor_state);
1183 				}
1184 			}
1185 
1186 			if (rv & DMA_CDB_STATUS_MSK) {
1187 				/* ZeroSum check failed
1188 				 */
1189 				struct ppc440spe_adma_desc_slot *iter;
1190 				dma_addr_t phys = rv & ~DMA_CDB_MSK;
1191 
1192 				/*
1193 				 * Update the status of corresponding
1194 				 * descriptor.
1195 				 */
1196 				list_for_each_entry(iter, &chan->chain,
1197 				    chain_node) {
1198 					if (iter->phys == phys)
1199 						break;
1200 				}
1201 				/*
1202 				 * if cannot find the corresponding
1203 				 * slot it's a bug
1204 				 */
1205 				BUG_ON(&iter->chain_node == &chan->chain);
1206 
1207 				if (iter->xor_check_result) {
1208 					if (test_bit(PPC440SPE_DESC_PCHECK,
1209 						     &iter->flags)) {
1210 						*iter->xor_check_result |=
1211 							SUM_CHECK_P_RESULT;
1212 					} else
1213 					if (test_bit(PPC440SPE_DESC_QCHECK,
1214 						     &iter->flags)) {
1215 						*iter->xor_check_result |=
1216 							SUM_CHECK_Q_RESULT;
1217 					} else
1218 						BUG();
1219 				}
1220 			}
1221 		}
1222 
1223 		rv = ioread32(&dma_reg->dsts);
1224 		if (rv) {
1225 			pr_err("DMA%d err status: 0x%x\n",
1226 			       chan->device->id, rv);
1227 			/* write back to clear */
1228 			iowrite32(rv, &dma_reg->dsts);
1229 		}
1230 		break;
1231 	case PPC440SPE_XOR_ID:
1232 		/* reset status bits to ack */
1233 		xor_reg = chan->device->xor_reg;
1234 		rv = ioread32be(&xor_reg->sr);
1235 		iowrite32be(rv, &xor_reg->sr);
1236 
1237 		if (rv & (XOR_IE_ICBIE_BIT|XOR_IE_ICIE_BIT|XOR_IE_RPTIE_BIT)) {
1238 			if (rv & XOR_IE_RPTIE_BIT) {
1239 				/* Read PLB Timeout Error.
1240 				 * Try to resubmit the CB
1241 				 */
1242 				u32 val = ioread32be(&xor_reg->ccbalr);
1243 
1244 				iowrite32be(val, &xor_reg->cblalr);
1245 
1246 				val = ioread32be(&xor_reg->crsr);
1247 				iowrite32be(val | XOR_CRSR_XAE_BIT,
1248 					    &xor_reg->crsr);
1249 			} else
1250 				pr_err("XOR ERR 0x%x status\n", rv);
1251 			break;
1252 		}
1253 
1254 		/*  if the XORcore is idle, but there are unprocessed CBs
1255 		 * then refetch the s/w chain here
1256 		 */
1257 		if (!(ioread32be(&xor_reg->sr) & XOR_SR_XCP_BIT) &&
1258 		    do_xor_refetch)
1259 			ppc440spe_chan_append(chan);
1260 		break;
1261 	}
1262 }
1263 
1264 /**
1265  * ppc440spe_chan_is_busy - get the channel status
1266  */
1267 static int ppc440spe_chan_is_busy(struct ppc440spe_adma_chan *chan)
1268 {
1269 	struct dma_regs *dma_reg;
1270 	struct xor_regs *xor_reg;
1271 	int busy = 0;
1272 
1273 	switch (chan->device->id) {
1274 	case PPC440SPE_DMA0_ID:
1275 	case PPC440SPE_DMA1_ID:
1276 		dma_reg = chan->device->dma_reg;
1277 		/*  if command FIFO's head and tail pointers are equal and
1278 		 * status tail is the same as command, then channel is free
1279 		 */
1280 		if (ioread16(&dma_reg->cpfhp) != ioread16(&dma_reg->cpftp) ||
1281 		    ioread16(&dma_reg->cpftp) != ioread16(&dma_reg->csftp))
1282 			busy = 1;
1283 		break;
1284 	case PPC440SPE_XOR_ID:
1285 		/* use the special status bit for the XORcore
1286 		 */
1287 		xor_reg = chan->device->xor_reg;
1288 		busy = (ioread32be(&xor_reg->sr) & XOR_SR_XCP_BIT) ? 1 : 0;
1289 		break;
1290 	}
1291 
1292 	return busy;
1293 }
1294 
1295 /**
1296  * ppc440spe_chan_set_first_xor_descriptor -  init XORcore chain
1297  */
1298 static void ppc440spe_chan_set_first_xor_descriptor(
1299 				struct ppc440spe_adma_chan *chan,
1300 				struct ppc440spe_adma_desc_slot *next_desc)
1301 {
1302 	struct xor_regs *xor_reg = chan->device->xor_reg;
1303 
1304 	if (ioread32be(&xor_reg->sr) & XOR_SR_XCP_BIT)
1305 		printk(KERN_INFO "%s: Warn: XORcore is running "
1306 			"when try to set the first CDB!\n",
1307 			__func__);
1308 
1309 	xor_last_submit = xor_last_linked = next_desc;
1310 
1311 	iowrite32be(XOR_CRSR_64BA_BIT, &xor_reg->crsr);
1312 
1313 	iowrite32be(next_desc->phys, &xor_reg->cblalr);
1314 	iowrite32be(0, &xor_reg->cblahr);
1315 	iowrite32be(ioread32be(&xor_reg->cbcr) | XOR_CBCR_LNK_BIT,
1316 		    &xor_reg->cbcr);
1317 
1318 	chan->hw_chain_inited = 1;
1319 }
1320 
1321 /**
1322  * ppc440spe_dma_put_desc - put DMA0,1 descriptor to FIFO.
1323  * called with irqs disabled
1324  */
1325 static void ppc440spe_dma_put_desc(struct ppc440spe_adma_chan *chan,
1326 		struct ppc440spe_adma_desc_slot *desc)
1327 {
1328 	u32 pcdb;
1329 	struct dma_regs *dma_reg = chan->device->dma_reg;
1330 
1331 	pcdb = desc->phys;
1332 	if (!test_bit(PPC440SPE_DESC_INT, &desc->flags))
1333 		pcdb |= DMA_CDB_NO_INT;
1334 
1335 	chan_last_sub[chan->device->id] = desc;
1336 
1337 	ADMA_LL_DBG(print_cb(chan, desc->hw_desc));
1338 
1339 	iowrite32(pcdb, &dma_reg->cpfpl);
1340 }
1341 
1342 /**
1343  * ppc440spe_chan_append - update the h/w chain in the channel
1344  */
1345 static void ppc440spe_chan_append(struct ppc440spe_adma_chan *chan)
1346 {
1347 	struct xor_regs *xor_reg;
1348 	struct ppc440spe_adma_desc_slot *iter;
1349 	struct xor_cb *xcb;
1350 	u32 cur_desc;
1351 	unsigned long flags;
1352 
1353 	local_irq_save(flags);
1354 
1355 	switch (chan->device->id) {
1356 	case PPC440SPE_DMA0_ID:
1357 	case PPC440SPE_DMA1_ID:
1358 		cur_desc = ppc440spe_chan_get_current_descriptor(chan);
1359 
1360 		if (likely(cur_desc)) {
1361 			iter = chan_last_sub[chan->device->id];
1362 			BUG_ON(!iter);
1363 		} else {
1364 			/* first peer */
1365 			iter = chan_first_cdb[chan->device->id];
1366 			BUG_ON(!iter);
1367 			ppc440spe_dma_put_desc(chan, iter);
1368 			chan->hw_chain_inited = 1;
1369 		}
1370 
1371 		/* is there something new to append */
1372 		if (!iter->hw_next)
1373 			break;
1374 
1375 		/* flush descriptors from the s/w queue to fifo */
1376 		list_for_each_entry_continue(iter, &chan->chain, chain_node) {
1377 			ppc440spe_dma_put_desc(chan, iter);
1378 			if (!iter->hw_next)
1379 				break;
1380 		}
1381 		break;
1382 	case PPC440SPE_XOR_ID:
1383 		/* update h/w links and refetch */
1384 		if (!xor_last_submit->hw_next)
1385 			break;
1386 
1387 		xor_reg = chan->device->xor_reg;
1388 		/* the last linked CDB has to generate an interrupt
1389 		 * that we'd be able to append the next lists to h/w
1390 		 * regardless of the XOR engine state at the moment of
1391 		 * appending of these next lists
1392 		 */
1393 		xcb = xor_last_linked->hw_desc;
1394 		xcb->cbc |= XOR_CBCR_CBCE_BIT;
1395 
1396 		if (!(ioread32be(&xor_reg->sr) & XOR_SR_XCP_BIT)) {
1397 			/* XORcore is idle. Refetch now */
1398 			do_xor_refetch = 0;
1399 			ppc440spe_xor_set_link(xor_last_submit,
1400 				xor_last_submit->hw_next);
1401 
1402 			ADMA_LL_DBG(print_cb_list(chan,
1403 				xor_last_submit->hw_next));
1404 
1405 			xor_last_submit = xor_last_linked;
1406 			iowrite32be(ioread32be(&xor_reg->crsr) |
1407 				    XOR_CRSR_RCBE_BIT | XOR_CRSR_64BA_BIT,
1408 				    &xor_reg->crsr);
1409 		} else {
1410 			/* XORcore is running. Refetch later in the handler */
1411 			do_xor_refetch = 1;
1412 		}
1413 
1414 		break;
1415 	}
1416 
1417 	local_irq_restore(flags);
1418 }
1419 
1420 /**
1421  * ppc440spe_chan_get_current_descriptor - get the currently executed descriptor
1422  */
1423 static u32
1424 ppc440spe_chan_get_current_descriptor(struct ppc440spe_adma_chan *chan)
1425 {
1426 	struct dma_regs *dma_reg;
1427 	struct xor_regs *xor_reg;
1428 
1429 	if (unlikely(!chan->hw_chain_inited))
1430 		/* h/w descriptor chain is not initialized yet */
1431 		return 0;
1432 
1433 	switch (chan->device->id) {
1434 	case PPC440SPE_DMA0_ID:
1435 	case PPC440SPE_DMA1_ID:
1436 		dma_reg = chan->device->dma_reg;
1437 		return ioread32(&dma_reg->acpl) & (~DMA_CDB_MSK);
1438 	case PPC440SPE_XOR_ID:
1439 		xor_reg = chan->device->xor_reg;
1440 		return ioread32be(&xor_reg->ccbalr);
1441 	}
1442 	return 0;
1443 }
1444 
1445 /**
1446  * ppc440spe_chan_run - enable the channel
1447  */
1448 static void ppc440spe_chan_run(struct ppc440spe_adma_chan *chan)
1449 {
1450 	struct xor_regs *xor_reg;
1451 
1452 	switch (chan->device->id) {
1453 	case PPC440SPE_DMA0_ID:
1454 	case PPC440SPE_DMA1_ID:
1455 		/* DMAs are always enabled, do nothing */
1456 		break;
1457 	case PPC440SPE_XOR_ID:
1458 		/* drain write buffer */
1459 		xor_reg = chan->device->xor_reg;
1460 
1461 		/* fetch descriptor pointed to in <link> */
1462 		iowrite32be(XOR_CRSR_64BA_BIT | XOR_CRSR_XAE_BIT,
1463 			    &xor_reg->crsr);
1464 		break;
1465 	}
1466 }
1467 
1468 /******************************************************************************
1469  * ADMA device level
1470  ******************************************************************************/
1471 
1472 static void ppc440spe_chan_start_null_xor(struct ppc440spe_adma_chan *chan);
1473 static int ppc440spe_adma_alloc_chan_resources(struct dma_chan *chan);
1474 
1475 static dma_cookie_t
1476 ppc440spe_adma_tx_submit(struct dma_async_tx_descriptor *tx);
1477 
1478 static void ppc440spe_adma_set_dest(struct ppc440spe_adma_desc_slot *tx,
1479 				    dma_addr_t addr, int index);
1480 static void
1481 ppc440spe_adma_memcpy_xor_set_src(struct ppc440spe_adma_desc_slot *tx,
1482 				  dma_addr_t addr, int index);
1483 
1484 static void
1485 ppc440spe_adma_pq_set_dest(struct ppc440spe_adma_desc_slot *tx,
1486 			   dma_addr_t *paddr, unsigned long flags);
1487 static void
1488 ppc440spe_adma_pq_set_src(struct ppc440spe_adma_desc_slot *tx,
1489 			  dma_addr_t addr, int index);
1490 static void
1491 ppc440spe_adma_pq_set_src_mult(struct ppc440spe_adma_desc_slot *tx,
1492 			       unsigned char mult, int index, int dst_pos);
1493 static void
1494 ppc440spe_adma_pqzero_sum_set_dest(struct ppc440spe_adma_desc_slot *tx,
1495 				   dma_addr_t paddr, dma_addr_t qaddr);
1496 
1497 static struct page *ppc440spe_rxor_srcs[32];
1498 
1499 /**
1500  * ppc440spe_can_rxor - check if the operands may be processed with RXOR
1501  */
1502 static int ppc440spe_can_rxor(struct page **srcs, int src_cnt, size_t len)
1503 {
1504 	int i, order = 0, state = 0;
1505 	int idx = 0;
1506 
1507 	if (unlikely(!(src_cnt > 1)))
1508 		return 0;
1509 
1510 	BUG_ON(src_cnt > ARRAY_SIZE(ppc440spe_rxor_srcs));
1511 
1512 	/* Skip holes in the source list before checking */
1513 	for (i = 0; i < src_cnt; i++) {
1514 		if (!srcs[i])
1515 			continue;
1516 		ppc440spe_rxor_srcs[idx++] = srcs[i];
1517 	}
1518 	src_cnt = idx;
1519 
1520 	for (i = 1; i < src_cnt; i++) {
1521 		char *cur_addr = page_address(ppc440spe_rxor_srcs[i]);
1522 		char *old_addr = page_address(ppc440spe_rxor_srcs[i - 1]);
1523 
1524 		switch (state) {
1525 		case 0:
1526 			if (cur_addr == old_addr + len) {
1527 				/* direct RXOR */
1528 				order = 1;
1529 				state = 1;
1530 			} else if (old_addr == cur_addr + len) {
1531 				/* reverse RXOR */
1532 				order = -1;
1533 				state = 1;
1534 			} else
1535 				goto out;
1536 			break;
1537 		case 1:
1538 			if ((i == src_cnt - 2) ||
1539 			    (order == -1 && cur_addr != old_addr - len)) {
1540 				order = 0;
1541 				state = 0;
1542 			} else if ((cur_addr == old_addr + len * order) ||
1543 				   (cur_addr == old_addr + 2 * len) ||
1544 				   (cur_addr == old_addr + 3 * len)) {
1545 				state = 2;
1546 			} else {
1547 				order = 0;
1548 				state = 0;
1549 			}
1550 			break;
1551 		case 2:
1552 			order = 0;
1553 			state = 0;
1554 			break;
1555 		}
1556 	}
1557 
1558 out:
1559 	if (state == 1 || state == 2)
1560 		return 1;
1561 
1562 	return 0;
1563 }
1564 
1565 /**
1566  * ppc440spe_adma_device_estimate - estimate the efficiency of processing
1567  *	the operation given on this channel. It's assumed that 'chan' is
1568  *	capable to process 'cap' type of operation.
1569  * @chan: channel to use
1570  * @cap: type of transaction
1571  * @dst_lst: array of destination pointers
1572  * @dst_cnt: number of destination operands
1573  * @src_lst: array of source pointers
1574  * @src_cnt: number of source operands
1575  * @src_sz: size of each source operand
1576  */
1577 static int ppc440spe_adma_estimate(struct dma_chan *chan,
1578 	enum dma_transaction_type cap, struct page **dst_lst, int dst_cnt,
1579 	struct page **src_lst, int src_cnt, size_t src_sz)
1580 {
1581 	int ef = 1;
1582 
1583 	if (cap == DMA_PQ || cap == DMA_PQ_VAL) {
1584 		/* If RAID-6 capabilities were not activated don't try
1585 		 * to use them
1586 		 */
1587 		if (unlikely(!ppc440spe_r6_enabled))
1588 			return -1;
1589 	}
1590 	/*  In the current implementation of ppc440spe ADMA driver it
1591 	 * makes sense to pick out only pq case, because it may be
1592 	 * processed:
1593 	 * (1) either using Biskup method on DMA2;
1594 	 * (2) or on DMA0/1.
1595 	 *  Thus we give a favour to (1) if the sources are suitable;
1596 	 * else let it be processed on one of the DMA0/1 engines.
1597 	 *  In the sum_product case where destination is also the
1598 	 * source process it on DMA0/1 only.
1599 	 */
1600 	if (cap == DMA_PQ && chan->chan_id == PPC440SPE_XOR_ID) {
1601 
1602 		if (dst_cnt == 1 && src_cnt == 2 && dst_lst[0] == src_lst[1])
1603 			ef = 0; /* sum_product case, process on DMA0/1 */
1604 		else if (ppc440spe_can_rxor(src_lst, src_cnt, src_sz))
1605 			ef = 3; /* override (DMA0/1 + idle) */
1606 		else
1607 			ef = 0; /* can't process on DMA2 if !rxor */
1608 	}
1609 
1610 	/* channel idleness increases the priority */
1611 	if (likely(ef) &&
1612 	    !ppc440spe_chan_is_busy(to_ppc440spe_adma_chan(chan)))
1613 		ef++;
1614 
1615 	return ef;
1616 }
1617 
1618 struct dma_chan *
1619 ppc440spe_async_tx_find_best_channel(enum dma_transaction_type cap,
1620 	struct page **dst_lst, int dst_cnt, struct page **src_lst,
1621 	int src_cnt, size_t src_sz)
1622 {
1623 	struct dma_chan *best_chan = NULL;
1624 	struct ppc_dma_chan_ref *ref;
1625 	int best_rank = -1;
1626 
1627 	if (unlikely(!src_sz))
1628 		return NULL;
1629 	if (src_sz > PAGE_SIZE) {
1630 		/*
1631 		 * should a user of the api ever pass > PAGE_SIZE requests
1632 		 * we sort out cases where temporary page-sized buffers
1633 		 * are used.
1634 		 */
1635 		switch (cap) {
1636 		case DMA_PQ:
1637 			if (src_cnt == 1 && dst_lst[1] == src_lst[0])
1638 				return NULL;
1639 			if (src_cnt == 2 && dst_lst[1] == src_lst[1])
1640 				return NULL;
1641 			break;
1642 		case DMA_PQ_VAL:
1643 		case DMA_XOR_VAL:
1644 			return NULL;
1645 		default:
1646 			break;
1647 		}
1648 	}
1649 
1650 	list_for_each_entry(ref, &ppc440spe_adma_chan_list, node) {
1651 		if (dma_has_cap(cap, ref->chan->device->cap_mask)) {
1652 			int rank;
1653 
1654 			rank = ppc440spe_adma_estimate(ref->chan, cap, dst_lst,
1655 					dst_cnt, src_lst, src_cnt, src_sz);
1656 			if (rank > best_rank) {
1657 				best_rank = rank;
1658 				best_chan = ref->chan;
1659 			}
1660 		}
1661 	}
1662 
1663 	return best_chan;
1664 }
1665 EXPORT_SYMBOL_GPL(ppc440spe_async_tx_find_best_channel);
1666 
1667 /**
1668  * ppc440spe_get_group_entry - get group entry with index idx
1669  * @tdesc: is the last allocated slot in the group.
1670  */
1671 static struct ppc440spe_adma_desc_slot *
1672 ppc440spe_get_group_entry(struct ppc440spe_adma_desc_slot *tdesc, u32 entry_idx)
1673 {
1674 	struct ppc440spe_adma_desc_slot *iter = tdesc->group_head;
1675 	int i = 0;
1676 
1677 	if (entry_idx < 0 || entry_idx >= (tdesc->src_cnt + tdesc->dst_cnt)) {
1678 		printk("%s: entry_idx %d, src_cnt %d, dst_cnt %d\n",
1679 			__func__, entry_idx, tdesc->src_cnt, tdesc->dst_cnt);
1680 		BUG();
1681 	}
1682 
1683 	list_for_each_entry(iter, &tdesc->group_list, chain_node) {
1684 		if (i++ == entry_idx)
1685 			break;
1686 	}
1687 	return iter;
1688 }
1689 
1690 /**
1691  * ppc440spe_adma_free_slots - flags descriptor slots for reuse
1692  * @slot: Slot to free
1693  * Caller must hold &ppc440spe_chan->lock while calling this function
1694  */
1695 static void ppc440spe_adma_free_slots(struct ppc440spe_adma_desc_slot *slot,
1696 				      struct ppc440spe_adma_chan *chan)
1697 {
1698 	int stride = slot->slots_per_op;
1699 
1700 	while (stride--) {
1701 		slot->slots_per_op = 0;
1702 		slot = list_entry(slot->slot_node.next,
1703 				struct ppc440spe_adma_desc_slot,
1704 				slot_node);
1705 	}
1706 }
1707 
1708 static void ppc440spe_adma_unmap(struct ppc440spe_adma_chan *chan,
1709 				 struct ppc440spe_adma_desc_slot *desc)
1710 {
1711 	u32 src_cnt, dst_cnt;
1712 	dma_addr_t addr;
1713 
1714 	/*
1715 	 * get the number of sources & destination
1716 	 * included in this descriptor and unmap
1717 	 * them all
1718 	 */
1719 	src_cnt = ppc440spe_desc_get_src_num(desc, chan);
1720 	dst_cnt = ppc440spe_desc_get_dst_num(desc, chan);
1721 
1722 	/* unmap destinations */
1723 	if (!(desc->async_tx.flags & DMA_COMPL_SKIP_DEST_UNMAP)) {
1724 		while (dst_cnt--) {
1725 			addr = ppc440spe_desc_get_dest_addr(
1726 				desc, chan, dst_cnt);
1727 			dma_unmap_page(chan->device->dev,
1728 					addr, desc->unmap_len,
1729 					DMA_FROM_DEVICE);
1730 		}
1731 	}
1732 
1733 	/* unmap sources */
1734 	if (!(desc->async_tx.flags & DMA_COMPL_SKIP_SRC_UNMAP)) {
1735 		while (src_cnt--) {
1736 			addr = ppc440spe_desc_get_src_addr(
1737 				desc, chan, src_cnt);
1738 			dma_unmap_page(chan->device->dev,
1739 					addr, desc->unmap_len,
1740 					DMA_TO_DEVICE);
1741 		}
1742 	}
1743 }
1744 
1745 /**
1746  * ppc440spe_adma_run_tx_complete_actions - call functions to be called
1747  * upon completion
1748  */
1749 static dma_cookie_t ppc440spe_adma_run_tx_complete_actions(
1750 		struct ppc440spe_adma_desc_slot *desc,
1751 		struct ppc440spe_adma_chan *chan,
1752 		dma_cookie_t cookie)
1753 {
1754 	int i;
1755 
1756 	BUG_ON(desc->async_tx.cookie < 0);
1757 	if (desc->async_tx.cookie > 0) {
1758 		cookie = desc->async_tx.cookie;
1759 		desc->async_tx.cookie = 0;
1760 
1761 		/* call the callback (must not sleep or submit new
1762 		 * operations to this channel)
1763 		 */
1764 		if (desc->async_tx.callback)
1765 			desc->async_tx.callback(
1766 				desc->async_tx.callback_param);
1767 
1768 		/* unmap dma addresses
1769 		 * (unmap_single vs unmap_page?)
1770 		 *
1771 		 * actually, ppc's dma_unmap_page() functions are empty, so
1772 		 * the following code is just for the sake of completeness
1773 		 */
1774 		if (chan && chan->needs_unmap && desc->group_head &&
1775 		     desc->unmap_len) {
1776 			struct ppc440spe_adma_desc_slot *unmap =
1777 							desc->group_head;
1778 			/* assume 1 slot per op always */
1779 			u32 slot_count = unmap->slot_cnt;
1780 
1781 			/* Run through the group list and unmap addresses */
1782 			for (i = 0; i < slot_count; i++) {
1783 				BUG_ON(!unmap);
1784 				ppc440spe_adma_unmap(chan, unmap);
1785 				unmap = unmap->hw_next;
1786 			}
1787 		}
1788 	}
1789 
1790 	/* run dependent operations */
1791 	dma_run_dependencies(&desc->async_tx);
1792 
1793 	return cookie;
1794 }
1795 
1796 /**
1797  * ppc440spe_adma_clean_slot - clean up CDB slot (if ack is set)
1798  */
1799 static int ppc440spe_adma_clean_slot(struct ppc440spe_adma_desc_slot *desc,
1800 		struct ppc440spe_adma_chan *chan)
1801 {
1802 	/* the client is allowed to attach dependent operations
1803 	 * until 'ack' is set
1804 	 */
1805 	if (!async_tx_test_ack(&desc->async_tx))
1806 		return 0;
1807 
1808 	/* leave the last descriptor in the chain
1809 	 * so we can append to it
1810 	 */
1811 	if (list_is_last(&desc->chain_node, &chan->chain) ||
1812 	    desc->phys == ppc440spe_chan_get_current_descriptor(chan))
1813 		return 1;
1814 
1815 	if (chan->device->id != PPC440SPE_XOR_ID) {
1816 		/* our DMA interrupt handler clears opc field of
1817 		 * each processed descriptor. For all types of
1818 		 * operations except for ZeroSum we do not actually
1819 		 * need ack from the interrupt handler. ZeroSum is a
1820 		 * special case since the result of this operation
1821 		 * is available from the handler only, so if we see
1822 		 * such type of descriptor (which is unprocessed yet)
1823 		 * then leave it in chain.
1824 		 */
1825 		struct dma_cdb *cdb = desc->hw_desc;
1826 		if (cdb->opc == DMA_CDB_OPC_DCHECK128)
1827 			return 1;
1828 	}
1829 
1830 	dev_dbg(chan->device->common.dev, "\tfree slot %llx: %d stride: %d\n",
1831 		desc->phys, desc->idx, desc->slots_per_op);
1832 
1833 	list_del(&desc->chain_node);
1834 	ppc440spe_adma_free_slots(desc, chan);
1835 	return 0;
1836 }
1837 
1838 /**
1839  * __ppc440spe_adma_slot_cleanup - this is the common clean-up routine
1840  *	which runs through the channel CDBs list until reach the descriptor
1841  *	currently processed. When routine determines that all CDBs of group
1842  *	are completed then corresponding callbacks (if any) are called and slots
1843  *	are freed.
1844  */
1845 static void __ppc440spe_adma_slot_cleanup(struct ppc440spe_adma_chan *chan)
1846 {
1847 	struct ppc440spe_adma_desc_slot *iter, *_iter, *group_start = NULL;
1848 	dma_cookie_t cookie = 0;
1849 	u32 current_desc = ppc440spe_chan_get_current_descriptor(chan);
1850 	int busy = ppc440spe_chan_is_busy(chan);
1851 	int seen_current = 0, slot_cnt = 0, slots_per_op = 0;
1852 
1853 	dev_dbg(chan->device->common.dev, "ppc440spe adma%d: %s\n",
1854 		chan->device->id, __func__);
1855 
1856 	if (!current_desc) {
1857 		/*  There were no transactions yet, so
1858 		 * nothing to clean
1859 		 */
1860 		return;
1861 	}
1862 
1863 	/* free completed slots from the chain starting with
1864 	 * the oldest descriptor
1865 	 */
1866 	list_for_each_entry_safe(iter, _iter, &chan->chain,
1867 					chain_node) {
1868 		dev_dbg(chan->device->common.dev, "\tcookie: %d slot: %d "
1869 		    "busy: %d this_desc: %#llx next_desc: %#x "
1870 		    "cur: %#x ack: %d\n",
1871 		    iter->async_tx.cookie, iter->idx, busy, iter->phys,
1872 		    ppc440spe_desc_get_link(iter, chan), current_desc,
1873 		    async_tx_test_ack(&iter->async_tx));
1874 		prefetch(_iter);
1875 		prefetch(&_iter->async_tx);
1876 
1877 		/* do not advance past the current descriptor loaded into the
1878 		 * hardware channel,subsequent descriptors are either in process
1879 		 * or have not been submitted
1880 		 */
1881 		if (seen_current)
1882 			break;
1883 
1884 		/* stop the search if we reach the current descriptor and the
1885 		 * channel is busy, or if it appears that the current descriptor
1886 		 * needs to be re-read (i.e. has been appended to)
1887 		 */
1888 		if (iter->phys == current_desc) {
1889 			BUG_ON(seen_current++);
1890 			if (busy || ppc440spe_desc_get_link(iter, chan)) {
1891 				/* not all descriptors of the group have
1892 				 * been completed; exit.
1893 				 */
1894 				break;
1895 			}
1896 		}
1897 
1898 		/* detect the start of a group transaction */
1899 		if (!slot_cnt && !slots_per_op) {
1900 			slot_cnt = iter->slot_cnt;
1901 			slots_per_op = iter->slots_per_op;
1902 			if (slot_cnt <= slots_per_op) {
1903 				slot_cnt = 0;
1904 				slots_per_op = 0;
1905 			}
1906 		}
1907 
1908 		if (slot_cnt) {
1909 			if (!group_start)
1910 				group_start = iter;
1911 			slot_cnt -= slots_per_op;
1912 		}
1913 
1914 		/* all the members of a group are complete */
1915 		if (slots_per_op != 0 && slot_cnt == 0) {
1916 			struct ppc440spe_adma_desc_slot *grp_iter, *_grp_iter;
1917 			int end_of_chain = 0;
1918 
1919 			/* clean up the group */
1920 			slot_cnt = group_start->slot_cnt;
1921 			grp_iter = group_start;
1922 			list_for_each_entry_safe_from(grp_iter, _grp_iter,
1923 				&chan->chain, chain_node) {
1924 
1925 				cookie = ppc440spe_adma_run_tx_complete_actions(
1926 					grp_iter, chan, cookie);
1927 
1928 				slot_cnt -= slots_per_op;
1929 				end_of_chain = ppc440spe_adma_clean_slot(
1930 				    grp_iter, chan);
1931 				if (end_of_chain && slot_cnt) {
1932 					/* Should wait for ZeroSum completion */
1933 					if (cookie > 0)
1934 						chan->common.completed_cookie = cookie;
1935 					return;
1936 				}
1937 
1938 				if (slot_cnt == 0 || end_of_chain)
1939 					break;
1940 			}
1941 
1942 			/* the group should be complete at this point */
1943 			BUG_ON(slot_cnt);
1944 
1945 			slots_per_op = 0;
1946 			group_start = NULL;
1947 			if (end_of_chain)
1948 				break;
1949 			else
1950 				continue;
1951 		} else if (slots_per_op) /* wait for group completion */
1952 			continue;
1953 
1954 		cookie = ppc440spe_adma_run_tx_complete_actions(iter, chan,
1955 		    cookie);
1956 
1957 		if (ppc440spe_adma_clean_slot(iter, chan))
1958 			break;
1959 	}
1960 
1961 	BUG_ON(!seen_current);
1962 
1963 	if (cookie > 0) {
1964 		chan->common.completed_cookie = cookie;
1965 		pr_debug("\tcompleted cookie %d\n", cookie);
1966 	}
1967 
1968 }
1969 
1970 /**
1971  * ppc440spe_adma_tasklet - clean up watch-dog initiator
1972  */
1973 static void ppc440spe_adma_tasklet(unsigned long data)
1974 {
1975 	struct ppc440spe_adma_chan *chan = (struct ppc440spe_adma_chan *) data;
1976 
1977 	spin_lock_nested(&chan->lock, SINGLE_DEPTH_NESTING);
1978 	__ppc440spe_adma_slot_cleanup(chan);
1979 	spin_unlock(&chan->lock);
1980 }
1981 
1982 /**
1983  * ppc440spe_adma_slot_cleanup - clean up scheduled initiator
1984  */
1985 static void ppc440spe_adma_slot_cleanup(struct ppc440spe_adma_chan *chan)
1986 {
1987 	spin_lock_bh(&chan->lock);
1988 	__ppc440spe_adma_slot_cleanup(chan);
1989 	spin_unlock_bh(&chan->lock);
1990 }
1991 
1992 /**
1993  * ppc440spe_adma_alloc_slots - allocate free slots (if any)
1994  */
1995 static struct ppc440spe_adma_desc_slot *ppc440spe_adma_alloc_slots(
1996 		struct ppc440spe_adma_chan *chan, int num_slots,
1997 		int slots_per_op)
1998 {
1999 	struct ppc440spe_adma_desc_slot *iter = NULL, *_iter;
2000 	struct ppc440spe_adma_desc_slot *alloc_start = NULL;
2001 	struct list_head chain = LIST_HEAD_INIT(chain);
2002 	int slots_found, retry = 0;
2003 
2004 
2005 	BUG_ON(!num_slots || !slots_per_op);
2006 	/* start search from the last allocated descrtiptor
2007 	 * if a contiguous allocation can not be found start searching
2008 	 * from the beginning of the list
2009 	 */
2010 retry:
2011 	slots_found = 0;
2012 	if (retry == 0)
2013 		iter = chan->last_used;
2014 	else
2015 		iter = list_entry(&chan->all_slots,
2016 				  struct ppc440spe_adma_desc_slot,
2017 				  slot_node);
2018 	list_for_each_entry_safe_continue(iter, _iter, &chan->all_slots,
2019 	    slot_node) {
2020 		prefetch(_iter);
2021 		prefetch(&_iter->async_tx);
2022 		if (iter->slots_per_op) {
2023 			slots_found = 0;
2024 			continue;
2025 		}
2026 
2027 		/* start the allocation if the slot is correctly aligned */
2028 		if (!slots_found++)
2029 			alloc_start = iter;
2030 
2031 		if (slots_found == num_slots) {
2032 			struct ppc440spe_adma_desc_slot *alloc_tail = NULL;
2033 			struct ppc440spe_adma_desc_slot *last_used = NULL;
2034 
2035 			iter = alloc_start;
2036 			while (num_slots) {
2037 				int i;
2038 				/* pre-ack all but the last descriptor */
2039 				if (num_slots != slots_per_op)
2040 					async_tx_ack(&iter->async_tx);
2041 
2042 				list_add_tail(&iter->chain_node, &chain);
2043 				alloc_tail = iter;
2044 				iter->async_tx.cookie = 0;
2045 				iter->hw_next = NULL;
2046 				iter->flags = 0;
2047 				iter->slot_cnt = num_slots;
2048 				iter->xor_check_result = NULL;
2049 				for (i = 0; i < slots_per_op; i++) {
2050 					iter->slots_per_op = slots_per_op - i;
2051 					last_used = iter;
2052 					iter = list_entry(iter->slot_node.next,
2053 						struct ppc440spe_adma_desc_slot,
2054 						slot_node);
2055 				}
2056 				num_slots -= slots_per_op;
2057 			}
2058 			alloc_tail->group_head = alloc_start;
2059 			alloc_tail->async_tx.cookie = -EBUSY;
2060 			list_splice(&chain, &alloc_tail->group_list);
2061 			chan->last_used = last_used;
2062 			return alloc_tail;
2063 		}
2064 	}
2065 	if (!retry++)
2066 		goto retry;
2067 
2068 	/* try to free some slots if the allocation fails */
2069 	tasklet_schedule(&chan->irq_tasklet);
2070 	return NULL;
2071 }
2072 
2073 /**
2074  * ppc440spe_adma_alloc_chan_resources -  allocate pools for CDB slots
2075  */
2076 static int ppc440spe_adma_alloc_chan_resources(struct dma_chan *chan)
2077 {
2078 	struct ppc440spe_adma_chan *ppc440spe_chan;
2079 	struct ppc440spe_adma_desc_slot *slot = NULL;
2080 	char *hw_desc;
2081 	int i, db_sz;
2082 	int init;
2083 
2084 	ppc440spe_chan = to_ppc440spe_adma_chan(chan);
2085 	init = ppc440spe_chan->slots_allocated ? 0 : 1;
2086 	chan->chan_id = ppc440spe_chan->device->id;
2087 
2088 	/* Allocate descriptor slots */
2089 	i = ppc440spe_chan->slots_allocated;
2090 	if (ppc440spe_chan->device->id != PPC440SPE_XOR_ID)
2091 		db_sz = sizeof(struct dma_cdb);
2092 	else
2093 		db_sz = sizeof(struct xor_cb);
2094 
2095 	for (; i < (ppc440spe_chan->device->pool_size / db_sz); i++) {
2096 		slot = kzalloc(sizeof(struct ppc440spe_adma_desc_slot),
2097 			       GFP_KERNEL);
2098 		if (!slot) {
2099 			printk(KERN_INFO "SPE ADMA Channel only initialized"
2100 				" %d descriptor slots", i--);
2101 			break;
2102 		}
2103 
2104 		hw_desc = (char *) ppc440spe_chan->device->dma_desc_pool_virt;
2105 		slot->hw_desc = (void *) &hw_desc[i * db_sz];
2106 		dma_async_tx_descriptor_init(&slot->async_tx, chan);
2107 		slot->async_tx.tx_submit = ppc440spe_adma_tx_submit;
2108 		INIT_LIST_HEAD(&slot->chain_node);
2109 		INIT_LIST_HEAD(&slot->slot_node);
2110 		INIT_LIST_HEAD(&slot->group_list);
2111 		slot->phys = ppc440spe_chan->device->dma_desc_pool + i * db_sz;
2112 		slot->idx = i;
2113 
2114 		spin_lock_bh(&ppc440spe_chan->lock);
2115 		ppc440spe_chan->slots_allocated++;
2116 		list_add_tail(&slot->slot_node, &ppc440spe_chan->all_slots);
2117 		spin_unlock_bh(&ppc440spe_chan->lock);
2118 	}
2119 
2120 	if (i && !ppc440spe_chan->last_used) {
2121 		ppc440spe_chan->last_used =
2122 			list_entry(ppc440spe_chan->all_slots.next,
2123 				struct ppc440spe_adma_desc_slot,
2124 				slot_node);
2125 	}
2126 
2127 	dev_dbg(ppc440spe_chan->device->common.dev,
2128 		"ppc440spe adma%d: allocated %d descriptor slots\n",
2129 		ppc440spe_chan->device->id, i);
2130 
2131 	/* initialize the channel and the chain with a null operation */
2132 	if (init) {
2133 		switch (ppc440spe_chan->device->id) {
2134 		case PPC440SPE_DMA0_ID:
2135 		case PPC440SPE_DMA1_ID:
2136 			ppc440spe_chan->hw_chain_inited = 0;
2137 			/* Use WXOR for self-testing */
2138 			if (!ppc440spe_r6_tchan)
2139 				ppc440spe_r6_tchan = ppc440spe_chan;
2140 			break;
2141 		case PPC440SPE_XOR_ID:
2142 			ppc440spe_chan_start_null_xor(ppc440spe_chan);
2143 			break;
2144 		default:
2145 			BUG();
2146 		}
2147 		ppc440spe_chan->needs_unmap = 1;
2148 	}
2149 
2150 	return (i > 0) ? i : -ENOMEM;
2151 }
2152 
2153 /**
2154  * ppc440spe_rxor_set_region_data -
2155  */
2156 static void ppc440spe_rxor_set_region(struct ppc440spe_adma_desc_slot *desc,
2157 	u8 xor_arg_no, u32 mask)
2158 {
2159 	struct xor_cb *xcb = desc->hw_desc;
2160 
2161 	xcb->ops[xor_arg_no].h |= mask;
2162 }
2163 
2164 /**
2165  * ppc440spe_rxor_set_src -
2166  */
2167 static void ppc440spe_rxor_set_src(struct ppc440spe_adma_desc_slot *desc,
2168 	u8 xor_arg_no, dma_addr_t addr)
2169 {
2170 	struct xor_cb *xcb = desc->hw_desc;
2171 
2172 	xcb->ops[xor_arg_no].h |= DMA_CUED_XOR_BASE;
2173 	xcb->ops[xor_arg_no].l = addr;
2174 }
2175 
2176 /**
2177  * ppc440spe_rxor_set_mult -
2178  */
2179 static void ppc440spe_rxor_set_mult(struct ppc440spe_adma_desc_slot *desc,
2180 	u8 xor_arg_no, u8 idx, u8 mult)
2181 {
2182 	struct xor_cb *xcb = desc->hw_desc;
2183 
2184 	xcb->ops[xor_arg_no].h |= mult << (DMA_CUED_MULT1_OFF + idx * 8);
2185 }
2186 
2187 /**
2188  * ppc440spe_adma_check_threshold - append CDBs to h/w chain if threshold
2189  *	has been achieved
2190  */
2191 static void ppc440spe_adma_check_threshold(struct ppc440spe_adma_chan *chan)
2192 {
2193 	dev_dbg(chan->device->common.dev, "ppc440spe adma%d: pending: %d\n",
2194 		chan->device->id, chan->pending);
2195 
2196 	if (chan->pending >= PPC440SPE_ADMA_THRESHOLD) {
2197 		chan->pending = 0;
2198 		ppc440spe_chan_append(chan);
2199 	}
2200 }
2201 
2202 /**
2203  * ppc440spe_adma_tx_submit - submit new descriptor group to the channel
2204  *	(it's not necessary that descriptors will be submitted to the h/w
2205  *	chains too right now)
2206  */
2207 static dma_cookie_t ppc440spe_adma_tx_submit(struct dma_async_tx_descriptor *tx)
2208 {
2209 	struct ppc440spe_adma_desc_slot *sw_desc;
2210 	struct ppc440spe_adma_chan *chan = to_ppc440spe_adma_chan(tx->chan);
2211 	struct ppc440spe_adma_desc_slot *group_start, *old_chain_tail;
2212 	int slot_cnt;
2213 	int slots_per_op;
2214 	dma_cookie_t cookie;
2215 
2216 	sw_desc = tx_to_ppc440spe_adma_slot(tx);
2217 
2218 	group_start = sw_desc->group_head;
2219 	slot_cnt = group_start->slot_cnt;
2220 	slots_per_op = group_start->slots_per_op;
2221 
2222 	spin_lock_bh(&chan->lock);
2223 	cookie = dma_cookie_assign(tx);
2224 
2225 	if (unlikely(list_empty(&chan->chain))) {
2226 		/* first peer */
2227 		list_splice_init(&sw_desc->group_list, &chan->chain);
2228 		chan_first_cdb[chan->device->id] = group_start;
2229 	} else {
2230 		/* isn't first peer, bind CDBs to chain */
2231 		old_chain_tail = list_entry(chan->chain.prev,
2232 					struct ppc440spe_adma_desc_slot,
2233 					chain_node);
2234 		list_splice_init(&sw_desc->group_list,
2235 		    &old_chain_tail->chain_node);
2236 		/* fix up the hardware chain */
2237 		ppc440spe_desc_set_link(chan, old_chain_tail, group_start);
2238 	}
2239 
2240 	/* increment the pending count by the number of operations */
2241 	chan->pending += slot_cnt / slots_per_op;
2242 	ppc440spe_adma_check_threshold(chan);
2243 	spin_unlock_bh(&chan->lock);
2244 
2245 	dev_dbg(chan->device->common.dev,
2246 		"ppc440spe adma%d: %s cookie: %d slot: %d tx %p\n",
2247 		chan->device->id, __func__,
2248 		sw_desc->async_tx.cookie, sw_desc->idx, sw_desc);
2249 
2250 	return cookie;
2251 }
2252 
2253 /**
2254  * ppc440spe_adma_prep_dma_interrupt - prepare CDB for a pseudo DMA operation
2255  */
2256 static struct dma_async_tx_descriptor *ppc440spe_adma_prep_dma_interrupt(
2257 		struct dma_chan *chan, unsigned long flags)
2258 {
2259 	struct ppc440spe_adma_chan *ppc440spe_chan;
2260 	struct ppc440spe_adma_desc_slot *sw_desc, *group_start;
2261 	int slot_cnt, slots_per_op;
2262 
2263 	ppc440spe_chan = to_ppc440spe_adma_chan(chan);
2264 
2265 	dev_dbg(ppc440spe_chan->device->common.dev,
2266 		"ppc440spe adma%d: %s\n", ppc440spe_chan->device->id,
2267 		__func__);
2268 
2269 	spin_lock_bh(&ppc440spe_chan->lock);
2270 	slot_cnt = slots_per_op = 1;
2271 	sw_desc = ppc440spe_adma_alloc_slots(ppc440spe_chan, slot_cnt,
2272 			slots_per_op);
2273 	if (sw_desc) {
2274 		group_start = sw_desc->group_head;
2275 		ppc440spe_desc_init_interrupt(group_start, ppc440spe_chan);
2276 		group_start->unmap_len = 0;
2277 		sw_desc->async_tx.flags = flags;
2278 	}
2279 	spin_unlock_bh(&ppc440spe_chan->lock);
2280 
2281 	return sw_desc ? &sw_desc->async_tx : NULL;
2282 }
2283 
2284 /**
2285  * ppc440spe_adma_prep_dma_memcpy - prepare CDB for a MEMCPY operation
2286  */
2287 static struct dma_async_tx_descriptor *ppc440spe_adma_prep_dma_memcpy(
2288 		struct dma_chan *chan, dma_addr_t dma_dest,
2289 		dma_addr_t dma_src, size_t len, unsigned long flags)
2290 {
2291 	struct ppc440spe_adma_chan *ppc440spe_chan;
2292 	struct ppc440spe_adma_desc_slot *sw_desc, *group_start;
2293 	int slot_cnt, slots_per_op;
2294 
2295 	ppc440spe_chan = to_ppc440spe_adma_chan(chan);
2296 
2297 	if (unlikely(!len))
2298 		return NULL;
2299 
2300 	BUG_ON(len > PPC440SPE_ADMA_DMA_MAX_BYTE_COUNT);
2301 
2302 	spin_lock_bh(&ppc440spe_chan->lock);
2303 
2304 	dev_dbg(ppc440spe_chan->device->common.dev,
2305 		"ppc440spe adma%d: %s len: %u int_en %d\n",
2306 		ppc440spe_chan->device->id, __func__, len,
2307 		flags & DMA_PREP_INTERRUPT ? 1 : 0);
2308 	slot_cnt = slots_per_op = 1;
2309 	sw_desc = ppc440spe_adma_alloc_slots(ppc440spe_chan, slot_cnt,
2310 		slots_per_op);
2311 	if (sw_desc) {
2312 		group_start = sw_desc->group_head;
2313 		ppc440spe_desc_init_memcpy(group_start, flags);
2314 		ppc440spe_adma_set_dest(group_start, dma_dest, 0);
2315 		ppc440spe_adma_memcpy_xor_set_src(group_start, dma_src, 0);
2316 		ppc440spe_desc_set_byte_count(group_start, ppc440spe_chan, len);
2317 		sw_desc->unmap_len = len;
2318 		sw_desc->async_tx.flags = flags;
2319 	}
2320 	spin_unlock_bh(&ppc440spe_chan->lock);
2321 
2322 	return sw_desc ? &sw_desc->async_tx : NULL;
2323 }
2324 
2325 /**
2326  * ppc440spe_adma_prep_dma_memset - prepare CDB for a MEMSET operation
2327  */
2328 static struct dma_async_tx_descriptor *ppc440spe_adma_prep_dma_memset(
2329 		struct dma_chan *chan, dma_addr_t dma_dest, int value,
2330 		size_t len, unsigned long flags)
2331 {
2332 	struct ppc440spe_adma_chan *ppc440spe_chan;
2333 	struct ppc440spe_adma_desc_slot *sw_desc, *group_start;
2334 	int slot_cnt, slots_per_op;
2335 
2336 	ppc440spe_chan = to_ppc440spe_adma_chan(chan);
2337 
2338 	if (unlikely(!len))
2339 		return NULL;
2340 
2341 	BUG_ON(len > PPC440SPE_ADMA_DMA_MAX_BYTE_COUNT);
2342 
2343 	spin_lock_bh(&ppc440spe_chan->lock);
2344 
2345 	dev_dbg(ppc440spe_chan->device->common.dev,
2346 		"ppc440spe adma%d: %s cal: %u len: %u int_en %d\n",
2347 		ppc440spe_chan->device->id, __func__, value, len,
2348 		flags & DMA_PREP_INTERRUPT ? 1 : 0);
2349 
2350 	slot_cnt = slots_per_op = 1;
2351 	sw_desc = ppc440spe_adma_alloc_slots(ppc440spe_chan, slot_cnt,
2352 		slots_per_op);
2353 	if (sw_desc) {
2354 		group_start = sw_desc->group_head;
2355 		ppc440spe_desc_init_memset(group_start, value, flags);
2356 		ppc440spe_adma_set_dest(group_start, dma_dest, 0);
2357 		ppc440spe_desc_set_byte_count(group_start, ppc440spe_chan, len);
2358 		sw_desc->unmap_len = len;
2359 		sw_desc->async_tx.flags = flags;
2360 	}
2361 	spin_unlock_bh(&ppc440spe_chan->lock);
2362 
2363 	return sw_desc ? &sw_desc->async_tx : NULL;
2364 }
2365 
2366 /**
2367  * ppc440spe_adma_prep_dma_xor - prepare CDB for a XOR operation
2368  */
2369 static struct dma_async_tx_descriptor *ppc440spe_adma_prep_dma_xor(
2370 		struct dma_chan *chan, dma_addr_t dma_dest,
2371 		dma_addr_t *dma_src, u32 src_cnt, size_t len,
2372 		unsigned long flags)
2373 {
2374 	struct ppc440spe_adma_chan *ppc440spe_chan;
2375 	struct ppc440spe_adma_desc_slot *sw_desc, *group_start;
2376 	int slot_cnt, slots_per_op;
2377 
2378 	ppc440spe_chan = to_ppc440spe_adma_chan(chan);
2379 
2380 	ADMA_LL_DBG(prep_dma_xor_dbg(ppc440spe_chan->device->id,
2381 				     dma_dest, dma_src, src_cnt));
2382 	if (unlikely(!len))
2383 		return NULL;
2384 	BUG_ON(len > PPC440SPE_ADMA_XOR_MAX_BYTE_COUNT);
2385 
2386 	dev_dbg(ppc440spe_chan->device->common.dev,
2387 		"ppc440spe adma%d: %s src_cnt: %d len: %u int_en: %d\n",
2388 		ppc440spe_chan->device->id, __func__, src_cnt, len,
2389 		flags & DMA_PREP_INTERRUPT ? 1 : 0);
2390 
2391 	spin_lock_bh(&ppc440spe_chan->lock);
2392 	slot_cnt = ppc440spe_chan_xor_slot_count(len, src_cnt, &slots_per_op);
2393 	sw_desc = ppc440spe_adma_alloc_slots(ppc440spe_chan, slot_cnt,
2394 			slots_per_op);
2395 	if (sw_desc) {
2396 		group_start = sw_desc->group_head;
2397 		ppc440spe_desc_init_xor(group_start, src_cnt, flags);
2398 		ppc440spe_adma_set_dest(group_start, dma_dest, 0);
2399 		while (src_cnt--)
2400 			ppc440spe_adma_memcpy_xor_set_src(group_start,
2401 				dma_src[src_cnt], src_cnt);
2402 		ppc440spe_desc_set_byte_count(group_start, ppc440spe_chan, len);
2403 		sw_desc->unmap_len = len;
2404 		sw_desc->async_tx.flags = flags;
2405 	}
2406 	spin_unlock_bh(&ppc440spe_chan->lock);
2407 
2408 	return sw_desc ? &sw_desc->async_tx : NULL;
2409 }
2410 
2411 static inline void
2412 ppc440spe_desc_set_xor_src_cnt(struct ppc440spe_adma_desc_slot *desc,
2413 				int src_cnt);
2414 static void ppc440spe_init_rxor_cursor(struct ppc440spe_rxor *cursor);
2415 
2416 /**
2417  * ppc440spe_adma_init_dma2rxor_slot -
2418  */
2419 static void ppc440spe_adma_init_dma2rxor_slot(
2420 		struct ppc440spe_adma_desc_slot *desc,
2421 		dma_addr_t *src, int src_cnt)
2422 {
2423 	int i;
2424 
2425 	/* initialize CDB */
2426 	for (i = 0; i < src_cnt; i++) {
2427 		ppc440spe_adma_dma2rxor_prep_src(desc, &desc->rxor_cursor, i,
2428 						 desc->src_cnt, (u32)src[i]);
2429 	}
2430 }
2431 
2432 /**
2433  * ppc440spe_dma01_prep_mult -
2434  * for Q operation where destination is also the source
2435  */
2436 static struct ppc440spe_adma_desc_slot *ppc440spe_dma01_prep_mult(
2437 		struct ppc440spe_adma_chan *ppc440spe_chan,
2438 		dma_addr_t *dst, int dst_cnt, dma_addr_t *src, int src_cnt,
2439 		const unsigned char *scf, size_t len, unsigned long flags)
2440 {
2441 	struct ppc440spe_adma_desc_slot *sw_desc = NULL;
2442 	unsigned long op = 0;
2443 	int slot_cnt;
2444 
2445 	set_bit(PPC440SPE_DESC_WXOR, &op);
2446 	slot_cnt = 2;
2447 
2448 	spin_lock_bh(&ppc440spe_chan->lock);
2449 
2450 	/* use WXOR, each descriptor occupies one slot */
2451 	sw_desc = ppc440spe_adma_alloc_slots(ppc440spe_chan, slot_cnt, 1);
2452 	if (sw_desc) {
2453 		struct ppc440spe_adma_chan *chan;
2454 		struct ppc440spe_adma_desc_slot *iter;
2455 		struct dma_cdb *hw_desc;
2456 
2457 		chan = to_ppc440spe_adma_chan(sw_desc->async_tx.chan);
2458 		set_bits(op, &sw_desc->flags);
2459 		sw_desc->src_cnt = src_cnt;
2460 		sw_desc->dst_cnt = dst_cnt;
2461 		/* First descriptor, zero data in the destination and copy it
2462 		 * to q page using MULTICAST transfer.
2463 		 */
2464 		iter = list_first_entry(&sw_desc->group_list,
2465 					struct ppc440spe_adma_desc_slot,
2466 					chain_node);
2467 		memset(iter->hw_desc, 0, sizeof(struct dma_cdb));
2468 		/* set 'next' pointer */
2469 		iter->hw_next = list_entry(iter->chain_node.next,
2470 					   struct ppc440spe_adma_desc_slot,
2471 					   chain_node);
2472 		clear_bit(PPC440SPE_DESC_INT, &iter->flags);
2473 		hw_desc = iter->hw_desc;
2474 		hw_desc->opc = DMA_CDB_OPC_MULTICAST;
2475 
2476 		ppc440spe_desc_set_dest_addr(iter, chan,
2477 					     DMA_CUED_XOR_BASE, dst[0], 0);
2478 		ppc440spe_desc_set_dest_addr(iter, chan, 0, dst[1], 1);
2479 		ppc440spe_desc_set_src_addr(iter, chan, 0, DMA_CUED_XOR_HB,
2480 					    src[0]);
2481 		ppc440spe_desc_set_byte_count(iter, ppc440spe_chan, len);
2482 		iter->unmap_len = len;
2483 
2484 		/*
2485 		 * Second descriptor, multiply data from the q page
2486 		 * and store the result in real destination.
2487 		 */
2488 		iter = list_first_entry(&iter->chain_node,
2489 					struct ppc440spe_adma_desc_slot,
2490 					chain_node);
2491 		memset(iter->hw_desc, 0, sizeof(struct dma_cdb));
2492 		iter->hw_next = NULL;
2493 		if (flags & DMA_PREP_INTERRUPT)
2494 			set_bit(PPC440SPE_DESC_INT, &iter->flags);
2495 		else
2496 			clear_bit(PPC440SPE_DESC_INT, &iter->flags);
2497 
2498 		hw_desc = iter->hw_desc;
2499 		hw_desc->opc = DMA_CDB_OPC_MV_SG1_SG2;
2500 		ppc440spe_desc_set_src_addr(iter, chan, 0,
2501 					    DMA_CUED_XOR_HB, dst[1]);
2502 		ppc440spe_desc_set_dest_addr(iter, chan,
2503 					     DMA_CUED_XOR_BASE, dst[0], 0);
2504 
2505 		ppc440spe_desc_set_src_mult(iter, chan, DMA_CUED_MULT1_OFF,
2506 					    DMA_CDB_SG_DST1, scf[0]);
2507 		ppc440spe_desc_set_byte_count(iter, ppc440spe_chan, len);
2508 		iter->unmap_len = len;
2509 		sw_desc->async_tx.flags = flags;
2510 	}
2511 
2512 	spin_unlock_bh(&ppc440spe_chan->lock);
2513 
2514 	return sw_desc;
2515 }
2516 
2517 /**
2518  * ppc440spe_dma01_prep_sum_product -
2519  * Dx = A*(P+Pxy) + B*(Q+Qxy) operation where destination is also
2520  * the source.
2521  */
2522 static struct ppc440spe_adma_desc_slot *ppc440spe_dma01_prep_sum_product(
2523 		struct ppc440spe_adma_chan *ppc440spe_chan,
2524 		dma_addr_t *dst, dma_addr_t *src, int src_cnt,
2525 		const unsigned char *scf, size_t len, unsigned long flags)
2526 {
2527 	struct ppc440spe_adma_desc_slot *sw_desc = NULL;
2528 	unsigned long op = 0;
2529 	int slot_cnt;
2530 
2531 	set_bit(PPC440SPE_DESC_WXOR, &op);
2532 	slot_cnt = 3;
2533 
2534 	spin_lock_bh(&ppc440spe_chan->lock);
2535 
2536 	/* WXOR, each descriptor occupies one slot */
2537 	sw_desc = ppc440spe_adma_alloc_slots(ppc440spe_chan, slot_cnt, 1);
2538 	if (sw_desc) {
2539 		struct ppc440spe_adma_chan *chan;
2540 		struct ppc440spe_adma_desc_slot *iter;
2541 		struct dma_cdb *hw_desc;
2542 
2543 		chan = to_ppc440spe_adma_chan(sw_desc->async_tx.chan);
2544 		set_bits(op, &sw_desc->flags);
2545 		sw_desc->src_cnt = src_cnt;
2546 		sw_desc->dst_cnt = 1;
2547 		/* 1st descriptor, src[1] data to q page and zero destination */
2548 		iter = list_first_entry(&sw_desc->group_list,
2549 					struct ppc440spe_adma_desc_slot,
2550 					chain_node);
2551 		memset(iter->hw_desc, 0, sizeof(struct dma_cdb));
2552 		iter->hw_next = list_entry(iter->chain_node.next,
2553 					   struct ppc440spe_adma_desc_slot,
2554 					   chain_node);
2555 		clear_bit(PPC440SPE_DESC_INT, &iter->flags);
2556 		hw_desc = iter->hw_desc;
2557 		hw_desc->opc = DMA_CDB_OPC_MULTICAST;
2558 
2559 		ppc440spe_desc_set_dest_addr(iter, chan, DMA_CUED_XOR_BASE,
2560 					     *dst, 0);
2561 		ppc440spe_desc_set_dest_addr(iter, chan, 0,
2562 					     ppc440spe_chan->qdest, 1);
2563 		ppc440spe_desc_set_src_addr(iter, chan, 0, DMA_CUED_XOR_HB,
2564 					    src[1]);
2565 		ppc440spe_desc_set_byte_count(iter, ppc440spe_chan, len);
2566 		iter->unmap_len = len;
2567 
2568 		/* 2nd descriptor, multiply src[1] data and store the
2569 		 * result in destination */
2570 		iter = list_first_entry(&iter->chain_node,
2571 					struct ppc440spe_adma_desc_slot,
2572 					chain_node);
2573 		memset(iter->hw_desc, 0, sizeof(struct dma_cdb));
2574 		/* set 'next' pointer */
2575 		iter->hw_next = list_entry(iter->chain_node.next,
2576 					   struct ppc440spe_adma_desc_slot,
2577 					   chain_node);
2578 		if (flags & DMA_PREP_INTERRUPT)
2579 			set_bit(PPC440SPE_DESC_INT, &iter->flags);
2580 		else
2581 			clear_bit(PPC440SPE_DESC_INT, &iter->flags);
2582 
2583 		hw_desc = iter->hw_desc;
2584 		hw_desc->opc = DMA_CDB_OPC_MV_SG1_SG2;
2585 		ppc440spe_desc_set_src_addr(iter, chan, 0, DMA_CUED_XOR_HB,
2586 					    ppc440spe_chan->qdest);
2587 		ppc440spe_desc_set_dest_addr(iter, chan, DMA_CUED_XOR_BASE,
2588 					     *dst, 0);
2589 		ppc440spe_desc_set_src_mult(iter, chan,	DMA_CUED_MULT1_OFF,
2590 					    DMA_CDB_SG_DST1, scf[1]);
2591 		ppc440spe_desc_set_byte_count(iter, ppc440spe_chan, len);
2592 		iter->unmap_len = len;
2593 
2594 		/*
2595 		 * 3rd descriptor, multiply src[0] data and xor it
2596 		 * with destination
2597 		 */
2598 		iter = list_first_entry(&iter->chain_node,
2599 					struct ppc440spe_adma_desc_slot,
2600 					chain_node);
2601 		memset(iter->hw_desc, 0, sizeof(struct dma_cdb));
2602 		iter->hw_next = NULL;
2603 		if (flags & DMA_PREP_INTERRUPT)
2604 			set_bit(PPC440SPE_DESC_INT, &iter->flags);
2605 		else
2606 			clear_bit(PPC440SPE_DESC_INT, &iter->flags);
2607 
2608 		hw_desc = iter->hw_desc;
2609 		hw_desc->opc = DMA_CDB_OPC_MV_SG1_SG2;
2610 		ppc440spe_desc_set_src_addr(iter, chan, 0, DMA_CUED_XOR_HB,
2611 					    src[0]);
2612 		ppc440spe_desc_set_dest_addr(iter, chan, DMA_CUED_XOR_BASE,
2613 					     *dst, 0);
2614 		ppc440spe_desc_set_src_mult(iter, chan, DMA_CUED_MULT1_OFF,
2615 					    DMA_CDB_SG_DST1, scf[0]);
2616 		ppc440spe_desc_set_byte_count(iter, ppc440spe_chan, len);
2617 		iter->unmap_len = len;
2618 		sw_desc->async_tx.flags = flags;
2619 	}
2620 
2621 	spin_unlock_bh(&ppc440spe_chan->lock);
2622 
2623 	return sw_desc;
2624 }
2625 
2626 static struct ppc440spe_adma_desc_slot *ppc440spe_dma01_prep_pq(
2627 		struct ppc440spe_adma_chan *ppc440spe_chan,
2628 		dma_addr_t *dst, int dst_cnt, dma_addr_t *src, int src_cnt,
2629 		const unsigned char *scf, size_t len, unsigned long flags)
2630 {
2631 	int slot_cnt;
2632 	struct ppc440spe_adma_desc_slot *sw_desc = NULL, *iter;
2633 	unsigned long op = 0;
2634 	unsigned char mult = 1;
2635 
2636 	pr_debug("%s: dst_cnt %d, src_cnt %d, len %d\n",
2637 		 __func__, dst_cnt, src_cnt, len);
2638 	/*  select operations WXOR/RXOR depending on the
2639 	 * source addresses of operators and the number
2640 	 * of destinations (RXOR support only Q-parity calculations)
2641 	 */
2642 	set_bit(PPC440SPE_DESC_WXOR, &op);
2643 	if (!test_and_set_bit(PPC440SPE_RXOR_RUN, &ppc440spe_rxor_state)) {
2644 		/* no active RXOR;
2645 		 * do RXOR if:
2646 		 * - there are more than 1 source,
2647 		 * - len is aligned on 512-byte boundary,
2648 		 * - source addresses fit to one of 4 possible regions.
2649 		 */
2650 		if (src_cnt > 1 &&
2651 		    !(len & MQ0_CF2H_RXOR_BS_MASK) &&
2652 		    (src[0] + len) == src[1]) {
2653 			/* may do RXOR R1 R2 */
2654 			set_bit(PPC440SPE_DESC_RXOR, &op);
2655 			if (src_cnt != 2) {
2656 				/* may try to enhance region of RXOR */
2657 				if ((src[1] + len) == src[2]) {
2658 					/* do RXOR R1 R2 R3 */
2659 					set_bit(PPC440SPE_DESC_RXOR123,
2660 						&op);
2661 				} else if ((src[1] + len * 2) == src[2]) {
2662 					/* do RXOR R1 R2 R4 */
2663 					set_bit(PPC440SPE_DESC_RXOR124, &op);
2664 				} else if ((src[1] + len * 3) == src[2]) {
2665 					/* do RXOR R1 R2 R5 */
2666 					set_bit(PPC440SPE_DESC_RXOR125,
2667 						&op);
2668 				} else {
2669 					/* do RXOR R1 R2 */
2670 					set_bit(PPC440SPE_DESC_RXOR12,
2671 						&op);
2672 				}
2673 			} else {
2674 				/* do RXOR R1 R2 */
2675 				set_bit(PPC440SPE_DESC_RXOR12, &op);
2676 			}
2677 		}
2678 
2679 		if (!test_bit(PPC440SPE_DESC_RXOR, &op)) {
2680 			/* can not do this operation with RXOR */
2681 			clear_bit(PPC440SPE_RXOR_RUN,
2682 				&ppc440spe_rxor_state);
2683 		} else {
2684 			/* can do; set block size right now */
2685 			ppc440spe_desc_set_rxor_block_size(len);
2686 		}
2687 	}
2688 
2689 	/* Number of necessary slots depends on operation type selected */
2690 	if (!test_bit(PPC440SPE_DESC_RXOR, &op)) {
2691 		/*  This is a WXOR only chain. Need descriptors for each
2692 		 * source to GF-XOR them with WXOR, and need descriptors
2693 		 * for each destination to zero them with WXOR
2694 		 */
2695 		slot_cnt = src_cnt;
2696 
2697 		if (flags & DMA_PREP_ZERO_P) {
2698 			slot_cnt++;
2699 			set_bit(PPC440SPE_ZERO_P, &op);
2700 		}
2701 		if (flags & DMA_PREP_ZERO_Q) {
2702 			slot_cnt++;
2703 			set_bit(PPC440SPE_ZERO_Q, &op);
2704 		}
2705 	} else {
2706 		/*  Need 1/2 descriptor for RXOR operation, and
2707 		 * need (src_cnt - (2 or 3)) for WXOR of sources
2708 		 * remained (if any)
2709 		 */
2710 		slot_cnt = dst_cnt;
2711 
2712 		if (flags & DMA_PREP_ZERO_P)
2713 			set_bit(PPC440SPE_ZERO_P, &op);
2714 		if (flags & DMA_PREP_ZERO_Q)
2715 			set_bit(PPC440SPE_ZERO_Q, &op);
2716 
2717 		if (test_bit(PPC440SPE_DESC_RXOR12, &op))
2718 			slot_cnt += src_cnt - 2;
2719 		else
2720 			slot_cnt += src_cnt - 3;
2721 
2722 		/*  Thus we have either RXOR only chain or
2723 		 * mixed RXOR/WXOR
2724 		 */
2725 		if (slot_cnt == dst_cnt)
2726 			/* RXOR only chain */
2727 			clear_bit(PPC440SPE_DESC_WXOR, &op);
2728 	}
2729 
2730 	spin_lock_bh(&ppc440spe_chan->lock);
2731 	/* for both RXOR/WXOR each descriptor occupies one slot */
2732 	sw_desc = ppc440spe_adma_alloc_slots(ppc440spe_chan, slot_cnt, 1);
2733 	if (sw_desc) {
2734 		ppc440spe_desc_init_dma01pq(sw_desc, dst_cnt, src_cnt,
2735 				flags, op);
2736 
2737 		/* setup dst/src/mult */
2738 		pr_debug("%s: set dst descriptor 0, 1: 0x%016llx, 0x%016llx\n",
2739 			 __func__, dst[0], dst[1]);
2740 		ppc440spe_adma_pq_set_dest(sw_desc, dst, flags);
2741 		while (src_cnt--) {
2742 			ppc440spe_adma_pq_set_src(sw_desc, src[src_cnt],
2743 						  src_cnt);
2744 
2745 			/* NOTE: "Multi = 0 is equivalent to = 1" as it
2746 			 * stated in 440SPSPe_RAID6_Addendum_UM_1_17.pdf
2747 			 * doesn't work for RXOR with DMA0/1! Instead, multi=0
2748 			 * leads to zeroing source data after RXOR.
2749 			 * So, for P case set-up mult=1 explicitly.
2750 			 */
2751 			if (!(flags & DMA_PREP_PQ_DISABLE_Q))
2752 				mult = scf[src_cnt];
2753 			ppc440spe_adma_pq_set_src_mult(sw_desc,
2754 				mult, src_cnt,  dst_cnt - 1);
2755 		}
2756 
2757 		/* Setup byte count foreach slot just allocated */
2758 		sw_desc->async_tx.flags = flags;
2759 		list_for_each_entry(iter, &sw_desc->group_list,
2760 				chain_node) {
2761 			ppc440spe_desc_set_byte_count(iter,
2762 				ppc440spe_chan, len);
2763 			iter->unmap_len = len;
2764 		}
2765 	}
2766 	spin_unlock_bh(&ppc440spe_chan->lock);
2767 
2768 	return sw_desc;
2769 }
2770 
2771 static struct ppc440spe_adma_desc_slot *ppc440spe_dma2_prep_pq(
2772 		struct ppc440spe_adma_chan *ppc440spe_chan,
2773 		dma_addr_t *dst, int dst_cnt, dma_addr_t *src, int src_cnt,
2774 		const unsigned char *scf, size_t len, unsigned long flags)
2775 {
2776 	int slot_cnt, descs_per_op;
2777 	struct ppc440spe_adma_desc_slot *sw_desc = NULL, *iter;
2778 	unsigned long op = 0;
2779 	unsigned char mult = 1;
2780 
2781 	BUG_ON(!dst_cnt);
2782 	/*pr_debug("%s: dst_cnt %d, src_cnt %d, len %d\n",
2783 		 __func__, dst_cnt, src_cnt, len);*/
2784 
2785 	spin_lock_bh(&ppc440spe_chan->lock);
2786 	descs_per_op = ppc440spe_dma2_pq_slot_count(src, src_cnt, len);
2787 	if (descs_per_op < 0) {
2788 		spin_unlock_bh(&ppc440spe_chan->lock);
2789 		return NULL;
2790 	}
2791 
2792 	/* depending on number of sources we have 1 or 2 RXOR chains */
2793 	slot_cnt = descs_per_op * dst_cnt;
2794 
2795 	sw_desc = ppc440spe_adma_alloc_slots(ppc440spe_chan, slot_cnt, 1);
2796 	if (sw_desc) {
2797 		op = slot_cnt;
2798 		sw_desc->async_tx.flags = flags;
2799 		list_for_each_entry(iter, &sw_desc->group_list, chain_node) {
2800 			ppc440spe_desc_init_dma2pq(iter, dst_cnt, src_cnt,
2801 				--op ? 0 : flags);
2802 			ppc440spe_desc_set_byte_count(iter, ppc440spe_chan,
2803 				len);
2804 			iter->unmap_len = len;
2805 
2806 			ppc440spe_init_rxor_cursor(&(iter->rxor_cursor));
2807 			iter->rxor_cursor.len = len;
2808 			iter->descs_per_op = descs_per_op;
2809 		}
2810 		op = 0;
2811 		list_for_each_entry(iter, &sw_desc->group_list, chain_node) {
2812 			op++;
2813 			if (op % descs_per_op == 0)
2814 				ppc440spe_adma_init_dma2rxor_slot(iter, src,
2815 								  src_cnt);
2816 			if (likely(!list_is_last(&iter->chain_node,
2817 						 &sw_desc->group_list))) {
2818 				/* set 'next' pointer */
2819 				iter->hw_next =
2820 					list_entry(iter->chain_node.next,
2821 						struct ppc440spe_adma_desc_slot,
2822 						chain_node);
2823 				ppc440spe_xor_set_link(iter, iter->hw_next);
2824 			} else {
2825 				/* this is the last descriptor. */
2826 				iter->hw_next = NULL;
2827 			}
2828 		}
2829 
2830 		/* fixup head descriptor */
2831 		sw_desc->dst_cnt = dst_cnt;
2832 		if (flags & DMA_PREP_ZERO_P)
2833 			set_bit(PPC440SPE_ZERO_P, &sw_desc->flags);
2834 		if (flags & DMA_PREP_ZERO_Q)
2835 			set_bit(PPC440SPE_ZERO_Q, &sw_desc->flags);
2836 
2837 		/* setup dst/src/mult */
2838 		ppc440spe_adma_pq_set_dest(sw_desc, dst, flags);
2839 
2840 		while (src_cnt--) {
2841 			/* handle descriptors (if dst_cnt == 2) inside
2842 			 * the ppc440spe_adma_pq_set_srcxxx() functions
2843 			 */
2844 			ppc440spe_adma_pq_set_src(sw_desc, src[src_cnt],
2845 						  src_cnt);
2846 			if (!(flags & DMA_PREP_PQ_DISABLE_Q))
2847 				mult = scf[src_cnt];
2848 			ppc440spe_adma_pq_set_src_mult(sw_desc,
2849 					mult, src_cnt, dst_cnt - 1);
2850 		}
2851 	}
2852 	spin_unlock_bh(&ppc440spe_chan->lock);
2853 	ppc440spe_desc_set_rxor_block_size(len);
2854 	return sw_desc;
2855 }
2856 
2857 /**
2858  * ppc440spe_adma_prep_dma_pq - prepare CDB (group) for a GF-XOR operation
2859  */
2860 static struct dma_async_tx_descriptor *ppc440spe_adma_prep_dma_pq(
2861 		struct dma_chan *chan, dma_addr_t *dst, dma_addr_t *src,
2862 		unsigned int src_cnt, const unsigned char *scf,
2863 		size_t len, unsigned long flags)
2864 {
2865 	struct ppc440spe_adma_chan *ppc440spe_chan;
2866 	struct ppc440spe_adma_desc_slot *sw_desc = NULL;
2867 	int dst_cnt = 0;
2868 
2869 	ppc440spe_chan = to_ppc440spe_adma_chan(chan);
2870 
2871 	ADMA_LL_DBG(prep_dma_pq_dbg(ppc440spe_chan->device->id,
2872 				    dst, src, src_cnt));
2873 	BUG_ON(!len);
2874 	BUG_ON(len > PPC440SPE_ADMA_XOR_MAX_BYTE_COUNT);
2875 	BUG_ON(!src_cnt);
2876 
2877 	if (src_cnt == 1 && dst[1] == src[0]) {
2878 		dma_addr_t dest[2];
2879 
2880 		/* dst[1] is real destination (Q) */
2881 		dest[0] = dst[1];
2882 		/* this is the page to multicast source data to */
2883 		dest[1] = ppc440spe_chan->qdest;
2884 		sw_desc = ppc440spe_dma01_prep_mult(ppc440spe_chan,
2885 				dest, 2, src, src_cnt, scf, len, flags);
2886 		return sw_desc ? &sw_desc->async_tx : NULL;
2887 	}
2888 
2889 	if (src_cnt == 2 && dst[1] == src[1]) {
2890 		sw_desc = ppc440spe_dma01_prep_sum_product(ppc440spe_chan,
2891 					&dst[1], src, 2, scf, len, flags);
2892 		return sw_desc ? &sw_desc->async_tx : NULL;
2893 	}
2894 
2895 	if (!(flags & DMA_PREP_PQ_DISABLE_P)) {
2896 		BUG_ON(!dst[0]);
2897 		dst_cnt++;
2898 		flags |= DMA_PREP_ZERO_P;
2899 	}
2900 
2901 	if (!(flags & DMA_PREP_PQ_DISABLE_Q)) {
2902 		BUG_ON(!dst[1]);
2903 		dst_cnt++;
2904 		flags |= DMA_PREP_ZERO_Q;
2905 	}
2906 
2907 	BUG_ON(!dst_cnt);
2908 
2909 	dev_dbg(ppc440spe_chan->device->common.dev,
2910 		"ppc440spe adma%d: %s src_cnt: %d len: %u int_en: %d\n",
2911 		ppc440spe_chan->device->id, __func__, src_cnt, len,
2912 		flags & DMA_PREP_INTERRUPT ? 1 : 0);
2913 
2914 	switch (ppc440spe_chan->device->id) {
2915 	case PPC440SPE_DMA0_ID:
2916 	case PPC440SPE_DMA1_ID:
2917 		sw_desc = ppc440spe_dma01_prep_pq(ppc440spe_chan,
2918 				dst, dst_cnt, src, src_cnt, scf,
2919 				len, flags);
2920 		break;
2921 
2922 	case PPC440SPE_XOR_ID:
2923 		sw_desc = ppc440spe_dma2_prep_pq(ppc440spe_chan,
2924 				dst, dst_cnt, src, src_cnt, scf,
2925 				len, flags);
2926 		break;
2927 	}
2928 
2929 	return sw_desc ? &sw_desc->async_tx : NULL;
2930 }
2931 
2932 /**
2933  * ppc440spe_adma_prep_dma_pqzero_sum - prepare CDB group for
2934  * a PQ_ZERO_SUM operation
2935  */
2936 static struct dma_async_tx_descriptor *ppc440spe_adma_prep_dma_pqzero_sum(
2937 		struct dma_chan *chan, dma_addr_t *pq, dma_addr_t *src,
2938 		unsigned int src_cnt, const unsigned char *scf, size_t len,
2939 		enum sum_check_flags *pqres, unsigned long flags)
2940 {
2941 	struct ppc440spe_adma_chan *ppc440spe_chan;
2942 	struct ppc440spe_adma_desc_slot *sw_desc, *iter;
2943 	dma_addr_t pdest, qdest;
2944 	int slot_cnt, slots_per_op, idst, dst_cnt;
2945 
2946 	ppc440spe_chan = to_ppc440spe_adma_chan(chan);
2947 
2948 	if (flags & DMA_PREP_PQ_DISABLE_P)
2949 		pdest = 0;
2950 	else
2951 		pdest = pq[0];
2952 
2953 	if (flags & DMA_PREP_PQ_DISABLE_Q)
2954 		qdest = 0;
2955 	else
2956 		qdest = pq[1];
2957 
2958 	ADMA_LL_DBG(prep_dma_pqzero_sum_dbg(ppc440spe_chan->device->id,
2959 					    src, src_cnt, scf));
2960 
2961 	/* Always use WXOR for P/Q calculations (two destinations).
2962 	 * Need 1 or 2 extra slots to verify results are zero.
2963 	 */
2964 	idst = dst_cnt = (pdest && qdest) ? 2 : 1;
2965 
2966 	/* One additional slot per destination to clone P/Q
2967 	 * before calculation (we have to preserve destinations).
2968 	 */
2969 	slot_cnt = src_cnt + dst_cnt * 2;
2970 	slots_per_op = 1;
2971 
2972 	spin_lock_bh(&ppc440spe_chan->lock);
2973 	sw_desc = ppc440spe_adma_alloc_slots(ppc440spe_chan, slot_cnt,
2974 					     slots_per_op);
2975 	if (sw_desc) {
2976 		ppc440spe_desc_init_dma01pqzero_sum(sw_desc, dst_cnt, src_cnt);
2977 
2978 		/* Setup byte count for each slot just allocated */
2979 		sw_desc->async_tx.flags = flags;
2980 		list_for_each_entry(iter, &sw_desc->group_list, chain_node) {
2981 			ppc440spe_desc_set_byte_count(iter, ppc440spe_chan,
2982 						      len);
2983 			iter->unmap_len = len;
2984 		}
2985 
2986 		if (pdest) {
2987 			struct dma_cdb *hw_desc;
2988 			struct ppc440spe_adma_chan *chan;
2989 
2990 			iter = sw_desc->group_head;
2991 			chan = to_ppc440spe_adma_chan(iter->async_tx.chan);
2992 			memset(iter->hw_desc, 0, sizeof(struct dma_cdb));
2993 			iter->hw_next = list_entry(iter->chain_node.next,
2994 						struct ppc440spe_adma_desc_slot,
2995 						chain_node);
2996 			hw_desc = iter->hw_desc;
2997 			hw_desc->opc = DMA_CDB_OPC_MV_SG1_SG2;
2998 			iter->src_cnt = 0;
2999 			iter->dst_cnt = 0;
3000 			ppc440spe_desc_set_dest_addr(iter, chan, 0,
3001 						     ppc440spe_chan->pdest, 0);
3002 			ppc440spe_desc_set_src_addr(iter, chan, 0, 0, pdest);
3003 			ppc440spe_desc_set_byte_count(iter, ppc440spe_chan,
3004 						      len);
3005 			iter->unmap_len = 0;
3006 			/* override pdest to preserve original P */
3007 			pdest = ppc440spe_chan->pdest;
3008 		}
3009 		if (qdest) {
3010 			struct dma_cdb *hw_desc;
3011 			struct ppc440spe_adma_chan *chan;
3012 
3013 			iter = list_first_entry(&sw_desc->group_list,
3014 						struct ppc440spe_adma_desc_slot,
3015 						chain_node);
3016 			chan = to_ppc440spe_adma_chan(iter->async_tx.chan);
3017 
3018 			if (pdest) {
3019 				iter = list_entry(iter->chain_node.next,
3020 						struct ppc440spe_adma_desc_slot,
3021 						chain_node);
3022 			}
3023 
3024 			memset(iter->hw_desc, 0, sizeof(struct dma_cdb));
3025 			iter->hw_next = list_entry(iter->chain_node.next,
3026 						struct ppc440spe_adma_desc_slot,
3027 						chain_node);
3028 			hw_desc = iter->hw_desc;
3029 			hw_desc->opc = DMA_CDB_OPC_MV_SG1_SG2;
3030 			iter->src_cnt = 0;
3031 			iter->dst_cnt = 0;
3032 			ppc440spe_desc_set_dest_addr(iter, chan, 0,
3033 						     ppc440spe_chan->qdest, 0);
3034 			ppc440spe_desc_set_src_addr(iter, chan, 0, 0, qdest);
3035 			ppc440spe_desc_set_byte_count(iter, ppc440spe_chan,
3036 						      len);
3037 			iter->unmap_len = 0;
3038 			/* override qdest to preserve original Q */
3039 			qdest = ppc440spe_chan->qdest;
3040 		}
3041 
3042 		/* Setup destinations for P/Q ops */
3043 		ppc440spe_adma_pqzero_sum_set_dest(sw_desc, pdest, qdest);
3044 
3045 		/* Setup zero QWORDs into DCHECK CDBs */
3046 		idst = dst_cnt;
3047 		list_for_each_entry_reverse(iter, &sw_desc->group_list,
3048 					    chain_node) {
3049 			/*
3050 			 * The last CDB corresponds to Q-parity check,
3051 			 * the one before last CDB corresponds
3052 			 * P-parity check
3053 			 */
3054 			if (idst == DMA_DEST_MAX_NUM) {
3055 				if (idst == dst_cnt) {
3056 					set_bit(PPC440SPE_DESC_QCHECK,
3057 						&iter->flags);
3058 				} else {
3059 					set_bit(PPC440SPE_DESC_PCHECK,
3060 						&iter->flags);
3061 				}
3062 			} else {
3063 				if (qdest) {
3064 					set_bit(PPC440SPE_DESC_QCHECK,
3065 						&iter->flags);
3066 				} else {
3067 					set_bit(PPC440SPE_DESC_PCHECK,
3068 						&iter->flags);
3069 				}
3070 			}
3071 			iter->xor_check_result = pqres;
3072 
3073 			/*
3074 			 * set it to zero, if check fail then result will
3075 			 * be updated
3076 			 */
3077 			*iter->xor_check_result = 0;
3078 			ppc440spe_desc_set_dcheck(iter, ppc440spe_chan,
3079 				ppc440spe_qword);
3080 
3081 			if (!(--dst_cnt))
3082 				break;
3083 		}
3084 
3085 		/* Setup sources and mults for P/Q ops */
3086 		list_for_each_entry_continue_reverse(iter, &sw_desc->group_list,
3087 						     chain_node) {
3088 			struct ppc440spe_adma_chan *chan;
3089 			u32 mult_dst;
3090 
3091 			chan = to_ppc440spe_adma_chan(iter->async_tx.chan);
3092 			ppc440spe_desc_set_src_addr(iter, chan, 0,
3093 						    DMA_CUED_XOR_HB,
3094 						    src[src_cnt - 1]);
3095 			if (qdest) {
3096 				mult_dst = (dst_cnt - 1) ? DMA_CDB_SG_DST2 :
3097 							   DMA_CDB_SG_DST1;
3098 				ppc440spe_desc_set_src_mult(iter, chan,
3099 							    DMA_CUED_MULT1_OFF,
3100 							    mult_dst,
3101 							    scf[src_cnt - 1]);
3102 			}
3103 			if (!(--src_cnt))
3104 				break;
3105 		}
3106 	}
3107 	spin_unlock_bh(&ppc440spe_chan->lock);
3108 	return sw_desc ? &sw_desc->async_tx : NULL;
3109 }
3110 
3111 /**
3112  * ppc440spe_adma_prep_dma_xor_zero_sum - prepare CDB group for
3113  * XOR ZERO_SUM operation
3114  */
3115 static struct dma_async_tx_descriptor *ppc440spe_adma_prep_dma_xor_zero_sum(
3116 		struct dma_chan *chan, dma_addr_t *src, unsigned int src_cnt,
3117 		size_t len, enum sum_check_flags *result, unsigned long flags)
3118 {
3119 	struct dma_async_tx_descriptor *tx;
3120 	dma_addr_t pq[2];
3121 
3122 	/* validate P, disable Q */
3123 	pq[0] = src[0];
3124 	pq[1] = 0;
3125 	flags |= DMA_PREP_PQ_DISABLE_Q;
3126 
3127 	tx = ppc440spe_adma_prep_dma_pqzero_sum(chan, pq, &src[1],
3128 						src_cnt - 1, 0, len,
3129 						result, flags);
3130 	return tx;
3131 }
3132 
3133 /**
3134  * ppc440spe_adma_set_dest - set destination address into descriptor
3135  */
3136 static void ppc440spe_adma_set_dest(struct ppc440spe_adma_desc_slot *sw_desc,
3137 		dma_addr_t addr, int index)
3138 {
3139 	struct ppc440spe_adma_chan *chan;
3140 
3141 	BUG_ON(index >= sw_desc->dst_cnt);
3142 
3143 	chan = to_ppc440spe_adma_chan(sw_desc->async_tx.chan);
3144 
3145 	switch (chan->device->id) {
3146 	case PPC440SPE_DMA0_ID:
3147 	case PPC440SPE_DMA1_ID:
3148 		/* to do: support transfers lengths >
3149 		 * PPC440SPE_ADMA_DMA/XOR_MAX_BYTE_COUNT
3150 		 */
3151 		ppc440spe_desc_set_dest_addr(sw_desc->group_head,
3152 			chan, 0, addr, index);
3153 		break;
3154 	case PPC440SPE_XOR_ID:
3155 		sw_desc = ppc440spe_get_group_entry(sw_desc, index);
3156 		ppc440spe_desc_set_dest_addr(sw_desc,
3157 			chan, 0, addr, index);
3158 		break;
3159 	}
3160 }
3161 
3162 static void ppc440spe_adma_pq_zero_op(struct ppc440spe_adma_desc_slot *iter,
3163 		struct ppc440spe_adma_chan *chan, dma_addr_t addr)
3164 {
3165 	/*  To clear destinations update the descriptor
3166 	 * (P or Q depending on index) as follows:
3167 	 * addr is destination (0 corresponds to SG2):
3168 	 */
3169 	ppc440spe_desc_set_dest_addr(iter, chan, DMA_CUED_XOR_BASE, addr, 0);
3170 
3171 	/* ... and the addr is source: */
3172 	ppc440spe_desc_set_src_addr(iter, chan, 0, DMA_CUED_XOR_HB, addr);
3173 
3174 	/* addr is always SG2 then the mult is always DST1 */
3175 	ppc440spe_desc_set_src_mult(iter, chan, DMA_CUED_MULT1_OFF,
3176 				    DMA_CDB_SG_DST1, 1);
3177 }
3178 
3179 /**
3180  * ppc440spe_adma_pq_set_dest - set destination address into descriptor
3181  * for the PQXOR operation
3182  */
3183 static void ppc440spe_adma_pq_set_dest(struct ppc440spe_adma_desc_slot *sw_desc,
3184 		dma_addr_t *addrs, unsigned long flags)
3185 {
3186 	struct ppc440spe_adma_desc_slot *iter;
3187 	struct ppc440spe_adma_chan *chan;
3188 	dma_addr_t paddr, qaddr;
3189 	dma_addr_t addr = 0, ppath, qpath;
3190 	int index = 0, i;
3191 
3192 	chan = to_ppc440spe_adma_chan(sw_desc->async_tx.chan);
3193 
3194 	if (flags & DMA_PREP_PQ_DISABLE_P)
3195 		paddr = 0;
3196 	else
3197 		paddr = addrs[0];
3198 
3199 	if (flags & DMA_PREP_PQ_DISABLE_Q)
3200 		qaddr = 0;
3201 	else
3202 		qaddr = addrs[1];
3203 
3204 	if (!paddr || !qaddr)
3205 		addr = paddr ? paddr : qaddr;
3206 
3207 	switch (chan->device->id) {
3208 	case PPC440SPE_DMA0_ID:
3209 	case PPC440SPE_DMA1_ID:
3210 		/* walk through the WXOR source list and set P/Q-destinations
3211 		 * for each slot:
3212 		 */
3213 		if (!test_bit(PPC440SPE_DESC_RXOR, &sw_desc->flags)) {
3214 			/* This is WXOR-only chain; may have 1/2 zero descs */
3215 			if (test_bit(PPC440SPE_ZERO_P, &sw_desc->flags))
3216 				index++;
3217 			if (test_bit(PPC440SPE_ZERO_Q, &sw_desc->flags))
3218 				index++;
3219 
3220 			iter = ppc440spe_get_group_entry(sw_desc, index);
3221 			if (addr) {
3222 				/* one destination */
3223 				list_for_each_entry_from(iter,
3224 					&sw_desc->group_list, chain_node)
3225 					ppc440spe_desc_set_dest_addr(iter, chan,
3226 						DMA_CUED_XOR_BASE, addr, 0);
3227 			} else {
3228 				/* two destinations */
3229 				list_for_each_entry_from(iter,
3230 					&sw_desc->group_list, chain_node) {
3231 					ppc440spe_desc_set_dest_addr(iter, chan,
3232 						DMA_CUED_XOR_BASE, paddr, 0);
3233 					ppc440spe_desc_set_dest_addr(iter, chan,
3234 						DMA_CUED_XOR_BASE, qaddr, 1);
3235 				}
3236 			}
3237 
3238 			if (index) {
3239 				/*  To clear destinations update the descriptor
3240 				 * (1st,2nd, or both depending on flags)
3241 				 */
3242 				index = 0;
3243 				if (test_bit(PPC440SPE_ZERO_P,
3244 						&sw_desc->flags)) {
3245 					iter = ppc440spe_get_group_entry(
3246 							sw_desc, index++);
3247 					ppc440spe_adma_pq_zero_op(iter, chan,
3248 							paddr);
3249 				}
3250 
3251 				if (test_bit(PPC440SPE_ZERO_Q,
3252 						&sw_desc->flags)) {
3253 					iter = ppc440spe_get_group_entry(
3254 							sw_desc, index++);
3255 					ppc440spe_adma_pq_zero_op(iter, chan,
3256 							qaddr);
3257 				}
3258 
3259 				return;
3260 			}
3261 		} else {
3262 			/* This is RXOR-only or RXOR/WXOR mixed chain */
3263 
3264 			/* If we want to include destination into calculations,
3265 			 * then make dest addresses cued with mult=1 (XOR).
3266 			 */
3267 			ppath = test_bit(PPC440SPE_ZERO_P, &sw_desc->flags) ?
3268 					DMA_CUED_XOR_HB :
3269 					DMA_CUED_XOR_BASE |
3270 						(1 << DMA_CUED_MULT1_OFF);
3271 			qpath = test_bit(PPC440SPE_ZERO_Q, &sw_desc->flags) ?
3272 					DMA_CUED_XOR_HB :
3273 					DMA_CUED_XOR_BASE |
3274 						(1 << DMA_CUED_MULT1_OFF);
3275 
3276 			/* Setup destination(s) in RXOR slot(s) */
3277 			iter = ppc440spe_get_group_entry(sw_desc, index++);
3278 			ppc440spe_desc_set_dest_addr(iter, chan,
3279 						paddr ? ppath : qpath,
3280 						paddr ? paddr : qaddr, 0);
3281 			if (!addr) {
3282 				/* two destinations */
3283 				iter = ppc440spe_get_group_entry(sw_desc,
3284 								 index++);
3285 				ppc440spe_desc_set_dest_addr(iter, chan,
3286 						qpath, qaddr, 0);
3287 			}
3288 
3289 			if (test_bit(PPC440SPE_DESC_WXOR, &sw_desc->flags)) {
3290 				/* Setup destination(s) in remaining WXOR
3291 				 * slots
3292 				 */
3293 				iter = ppc440spe_get_group_entry(sw_desc,
3294 								 index);
3295 				if (addr) {
3296 					/* one destination */
3297 					list_for_each_entry_from(iter,
3298 					    &sw_desc->group_list,
3299 					    chain_node)
3300 						ppc440spe_desc_set_dest_addr(
3301 							iter, chan,
3302 							DMA_CUED_XOR_BASE,
3303 							addr, 0);
3304 
3305 				} else {
3306 					/* two destinations */
3307 					list_for_each_entry_from(iter,
3308 					    &sw_desc->group_list,
3309 					    chain_node) {
3310 						ppc440spe_desc_set_dest_addr(
3311 							iter, chan,
3312 							DMA_CUED_XOR_BASE,
3313 							paddr, 0);
3314 						ppc440spe_desc_set_dest_addr(
3315 							iter, chan,
3316 							DMA_CUED_XOR_BASE,
3317 							qaddr, 1);
3318 					}
3319 				}
3320 			}
3321 
3322 		}
3323 		break;
3324 
3325 	case PPC440SPE_XOR_ID:
3326 		/* DMA2 descriptors have only 1 destination, so there are
3327 		 * two chains - one for each dest.
3328 		 * If we want to include destination into calculations,
3329 		 * then make dest addresses cued with mult=1 (XOR).
3330 		 */
3331 		ppath = test_bit(PPC440SPE_ZERO_P, &sw_desc->flags) ?
3332 				DMA_CUED_XOR_HB :
3333 				DMA_CUED_XOR_BASE |
3334 					(1 << DMA_CUED_MULT1_OFF);
3335 
3336 		qpath = test_bit(PPC440SPE_ZERO_Q, &sw_desc->flags) ?
3337 				DMA_CUED_XOR_HB :
3338 				DMA_CUED_XOR_BASE |
3339 					(1 << DMA_CUED_MULT1_OFF);
3340 
3341 		iter = ppc440spe_get_group_entry(sw_desc, 0);
3342 		for (i = 0; i < sw_desc->descs_per_op; i++) {
3343 			ppc440spe_desc_set_dest_addr(iter, chan,
3344 				paddr ? ppath : qpath,
3345 				paddr ? paddr : qaddr, 0);
3346 			iter = list_entry(iter->chain_node.next,
3347 					  struct ppc440spe_adma_desc_slot,
3348 					  chain_node);
3349 		}
3350 
3351 		if (!addr) {
3352 			/* Two destinations; setup Q here */
3353 			iter = ppc440spe_get_group_entry(sw_desc,
3354 				sw_desc->descs_per_op);
3355 			for (i = 0; i < sw_desc->descs_per_op; i++) {
3356 				ppc440spe_desc_set_dest_addr(iter,
3357 					chan, qpath, qaddr, 0);
3358 				iter = list_entry(iter->chain_node.next,
3359 						struct ppc440spe_adma_desc_slot,
3360 						chain_node);
3361 			}
3362 		}
3363 
3364 		break;
3365 	}
3366 }
3367 
3368 /**
3369  * ppc440spe_adma_pq_zero_sum_set_dest - set destination address into descriptor
3370  * for the PQ_ZERO_SUM operation
3371  */
3372 static void ppc440spe_adma_pqzero_sum_set_dest(
3373 		struct ppc440spe_adma_desc_slot *sw_desc,
3374 		dma_addr_t paddr, dma_addr_t qaddr)
3375 {
3376 	struct ppc440spe_adma_desc_slot *iter, *end;
3377 	struct ppc440spe_adma_chan *chan;
3378 	dma_addr_t addr = 0;
3379 	int idx;
3380 
3381 	chan = to_ppc440spe_adma_chan(sw_desc->async_tx.chan);
3382 
3383 	/* walk through the WXOR source list and set P/Q-destinations
3384 	 * for each slot
3385 	 */
3386 	idx = (paddr && qaddr) ? 2 : 1;
3387 	/* set end */
3388 	list_for_each_entry_reverse(end, &sw_desc->group_list,
3389 				    chain_node) {
3390 		if (!(--idx))
3391 			break;
3392 	}
3393 	/* set start */
3394 	idx = (paddr && qaddr) ? 2 : 1;
3395 	iter = ppc440spe_get_group_entry(sw_desc, idx);
3396 
3397 	if (paddr && qaddr) {
3398 		/* two destinations */
3399 		list_for_each_entry_from(iter, &sw_desc->group_list,
3400 					 chain_node) {
3401 			if (unlikely(iter == end))
3402 				break;
3403 			ppc440spe_desc_set_dest_addr(iter, chan,
3404 						DMA_CUED_XOR_BASE, paddr, 0);
3405 			ppc440spe_desc_set_dest_addr(iter, chan,
3406 						DMA_CUED_XOR_BASE, qaddr, 1);
3407 		}
3408 	} else {
3409 		/* one destination */
3410 		addr = paddr ? paddr : qaddr;
3411 		list_for_each_entry_from(iter, &sw_desc->group_list,
3412 					 chain_node) {
3413 			if (unlikely(iter == end))
3414 				break;
3415 			ppc440spe_desc_set_dest_addr(iter, chan,
3416 						DMA_CUED_XOR_BASE, addr, 0);
3417 		}
3418 	}
3419 
3420 	/*  The remaining descriptors are DATACHECK. These have no need in
3421 	 * destination. Actually, these destinations are used there
3422 	 * as sources for check operation. So, set addr as source.
3423 	 */
3424 	ppc440spe_desc_set_src_addr(end, chan, 0, 0, addr ? addr : paddr);
3425 
3426 	if (!addr) {
3427 		end = list_entry(end->chain_node.next,
3428 				 struct ppc440spe_adma_desc_slot, chain_node);
3429 		ppc440spe_desc_set_src_addr(end, chan, 0, 0, qaddr);
3430 	}
3431 }
3432 
3433 /**
3434  * ppc440spe_desc_set_xor_src_cnt - set source count into descriptor
3435  */
3436 static inline void ppc440spe_desc_set_xor_src_cnt(
3437 			struct ppc440spe_adma_desc_slot *desc,
3438 			int src_cnt)
3439 {
3440 	struct xor_cb *hw_desc = desc->hw_desc;
3441 
3442 	hw_desc->cbc &= ~XOR_CDCR_OAC_MSK;
3443 	hw_desc->cbc |= src_cnt;
3444 }
3445 
3446 /**
3447  * ppc440spe_adma_pq_set_src - set source address into descriptor
3448  */
3449 static void ppc440spe_adma_pq_set_src(struct ppc440spe_adma_desc_slot *sw_desc,
3450 		dma_addr_t addr, int index)
3451 {
3452 	struct ppc440spe_adma_chan *chan;
3453 	dma_addr_t haddr = 0;
3454 	struct ppc440spe_adma_desc_slot *iter = NULL;
3455 
3456 	chan = to_ppc440spe_adma_chan(sw_desc->async_tx.chan);
3457 
3458 	switch (chan->device->id) {
3459 	case PPC440SPE_DMA0_ID:
3460 	case PPC440SPE_DMA1_ID:
3461 		/* DMA0,1 may do: WXOR, RXOR, RXOR+WXORs chain
3462 		 */
3463 		if (test_bit(PPC440SPE_DESC_RXOR, &sw_desc->flags)) {
3464 			/* RXOR-only or RXOR/WXOR operation */
3465 			int iskip = test_bit(PPC440SPE_DESC_RXOR12,
3466 				&sw_desc->flags) ?  2 : 3;
3467 
3468 			if (index == 0) {
3469 				/* 1st slot (RXOR) */
3470 				/* setup sources region (R1-2-3, R1-2-4,
3471 				 * or R1-2-5)
3472 				 */
3473 				if (test_bit(PPC440SPE_DESC_RXOR12,
3474 						&sw_desc->flags))
3475 					haddr = DMA_RXOR12 <<
3476 						DMA_CUED_REGION_OFF;
3477 				else if (test_bit(PPC440SPE_DESC_RXOR123,
3478 				    &sw_desc->flags))
3479 					haddr = DMA_RXOR123 <<
3480 						DMA_CUED_REGION_OFF;
3481 				else if (test_bit(PPC440SPE_DESC_RXOR124,
3482 				    &sw_desc->flags))
3483 					haddr = DMA_RXOR124 <<
3484 						DMA_CUED_REGION_OFF;
3485 				else if (test_bit(PPC440SPE_DESC_RXOR125,
3486 				    &sw_desc->flags))
3487 					haddr = DMA_RXOR125 <<
3488 						DMA_CUED_REGION_OFF;
3489 				else
3490 					BUG();
3491 				haddr |= DMA_CUED_XOR_BASE;
3492 				iter = ppc440spe_get_group_entry(sw_desc, 0);
3493 			} else if (index < iskip) {
3494 				/* 1st slot (RXOR)
3495 				 * shall actually set source address only once
3496 				 * instead of first <iskip>
3497 				 */
3498 				iter = NULL;
3499 			} else {
3500 				/* 2nd/3d and next slots (WXOR);
3501 				 * skip first slot with RXOR
3502 				 */
3503 				haddr = DMA_CUED_XOR_HB;
3504 				iter = ppc440spe_get_group_entry(sw_desc,
3505 				    index - iskip + sw_desc->dst_cnt);
3506 			}
3507 		} else {
3508 			int znum = 0;
3509 
3510 			/* WXOR-only operation; skip first slots with
3511 			 * zeroing destinations
3512 			 */
3513 			if (test_bit(PPC440SPE_ZERO_P, &sw_desc->flags))
3514 				znum++;
3515 			if (test_bit(PPC440SPE_ZERO_Q, &sw_desc->flags))
3516 				znum++;
3517 
3518 			haddr = DMA_CUED_XOR_HB;
3519 			iter = ppc440spe_get_group_entry(sw_desc,
3520 					index + znum);
3521 		}
3522 
3523 		if (likely(iter)) {
3524 			ppc440spe_desc_set_src_addr(iter, chan, 0, haddr, addr);
3525 
3526 			if (!index &&
3527 			    test_bit(PPC440SPE_DESC_RXOR, &sw_desc->flags) &&
3528 			    sw_desc->dst_cnt == 2) {
3529 				/* if we have two destinations for RXOR, then
3530 				 * setup source in the second descr too
3531 				 */
3532 				iter = ppc440spe_get_group_entry(sw_desc, 1);
3533 				ppc440spe_desc_set_src_addr(iter, chan, 0,
3534 					haddr, addr);
3535 			}
3536 		}
3537 		break;
3538 
3539 	case PPC440SPE_XOR_ID:
3540 		/* DMA2 may do Biskup */
3541 		iter = sw_desc->group_head;
3542 		if (iter->dst_cnt == 2) {
3543 			/* both P & Q calculations required; set P src here */
3544 			ppc440spe_adma_dma2rxor_set_src(iter, index, addr);
3545 
3546 			/* this is for Q */
3547 			iter = ppc440spe_get_group_entry(sw_desc,
3548 				sw_desc->descs_per_op);
3549 		}
3550 		ppc440spe_adma_dma2rxor_set_src(iter, index, addr);
3551 		break;
3552 	}
3553 }
3554 
3555 /**
3556  * ppc440spe_adma_memcpy_xor_set_src - set source address into descriptor
3557  */
3558 static void ppc440spe_adma_memcpy_xor_set_src(
3559 		struct ppc440spe_adma_desc_slot *sw_desc,
3560 		dma_addr_t addr, int index)
3561 {
3562 	struct ppc440spe_adma_chan *chan;
3563 
3564 	chan = to_ppc440spe_adma_chan(sw_desc->async_tx.chan);
3565 	sw_desc = sw_desc->group_head;
3566 
3567 	if (likely(sw_desc))
3568 		ppc440spe_desc_set_src_addr(sw_desc, chan, index, 0, addr);
3569 }
3570 
3571 /**
3572  * ppc440spe_adma_dma2rxor_inc_addr  -
3573  */
3574 static void ppc440spe_adma_dma2rxor_inc_addr(
3575 		struct ppc440spe_adma_desc_slot *desc,
3576 		struct ppc440spe_rxor *cursor, int index, int src_cnt)
3577 {
3578 	cursor->addr_count++;
3579 	if (index == src_cnt - 1) {
3580 		ppc440spe_desc_set_xor_src_cnt(desc, cursor->addr_count);
3581 	} else if (cursor->addr_count == XOR_MAX_OPS) {
3582 		ppc440spe_desc_set_xor_src_cnt(desc, cursor->addr_count);
3583 		cursor->addr_count = 0;
3584 		cursor->desc_count++;
3585 	}
3586 }
3587 
3588 /**
3589  * ppc440spe_adma_dma2rxor_prep_src - setup RXOR types in DMA2 CDB
3590  */
3591 static int ppc440spe_adma_dma2rxor_prep_src(
3592 		struct ppc440spe_adma_desc_slot *hdesc,
3593 		struct ppc440spe_rxor *cursor, int index,
3594 		int src_cnt, u32 addr)
3595 {
3596 	int rval = 0;
3597 	u32 sign;
3598 	struct ppc440spe_adma_desc_slot *desc = hdesc;
3599 	int i;
3600 
3601 	for (i = 0; i < cursor->desc_count; i++) {
3602 		desc = list_entry(hdesc->chain_node.next,
3603 				  struct ppc440spe_adma_desc_slot,
3604 				  chain_node);
3605 	}
3606 
3607 	switch (cursor->state) {
3608 	case 0:
3609 		if (addr == cursor->addrl + cursor->len) {
3610 			/* direct RXOR */
3611 			cursor->state = 1;
3612 			cursor->xor_count++;
3613 			if (index == src_cnt-1) {
3614 				ppc440spe_rxor_set_region(desc,
3615 					cursor->addr_count,
3616 					DMA_RXOR12 << DMA_CUED_REGION_OFF);
3617 				ppc440spe_adma_dma2rxor_inc_addr(
3618 					desc, cursor, index, src_cnt);
3619 			}
3620 		} else if (cursor->addrl == addr + cursor->len) {
3621 			/* reverse RXOR */
3622 			cursor->state = 1;
3623 			cursor->xor_count++;
3624 			set_bit(cursor->addr_count, &desc->reverse_flags[0]);
3625 			if (index == src_cnt-1) {
3626 				ppc440spe_rxor_set_region(desc,
3627 					cursor->addr_count,
3628 					DMA_RXOR12 << DMA_CUED_REGION_OFF);
3629 				ppc440spe_adma_dma2rxor_inc_addr(
3630 					desc, cursor, index, src_cnt);
3631 			}
3632 		} else {
3633 			printk(KERN_ERR "Cannot build "
3634 				"DMA2 RXOR command block.\n");
3635 			BUG();
3636 		}
3637 		break;
3638 	case 1:
3639 		sign = test_bit(cursor->addr_count,
3640 				desc->reverse_flags)
3641 			? -1 : 1;
3642 		if (index == src_cnt-2 || (sign == -1
3643 			&& addr != cursor->addrl - 2*cursor->len)) {
3644 			cursor->state = 0;
3645 			cursor->xor_count = 1;
3646 			cursor->addrl = addr;
3647 			ppc440spe_rxor_set_region(desc,
3648 				cursor->addr_count,
3649 				DMA_RXOR12 << DMA_CUED_REGION_OFF);
3650 			ppc440spe_adma_dma2rxor_inc_addr(
3651 				desc, cursor, index, src_cnt);
3652 		} else if (addr == cursor->addrl + 2*sign*cursor->len) {
3653 			cursor->state = 2;
3654 			cursor->xor_count = 0;
3655 			ppc440spe_rxor_set_region(desc,
3656 				cursor->addr_count,
3657 				DMA_RXOR123 << DMA_CUED_REGION_OFF);
3658 			if (index == src_cnt-1) {
3659 				ppc440spe_adma_dma2rxor_inc_addr(
3660 					desc, cursor, index, src_cnt);
3661 			}
3662 		} else if (addr == cursor->addrl + 3*cursor->len) {
3663 			cursor->state = 2;
3664 			cursor->xor_count = 0;
3665 			ppc440spe_rxor_set_region(desc,
3666 				cursor->addr_count,
3667 				DMA_RXOR124 << DMA_CUED_REGION_OFF);
3668 			if (index == src_cnt-1) {
3669 				ppc440spe_adma_dma2rxor_inc_addr(
3670 					desc, cursor, index, src_cnt);
3671 			}
3672 		} else if (addr == cursor->addrl + 4*cursor->len) {
3673 			cursor->state = 2;
3674 			cursor->xor_count = 0;
3675 			ppc440spe_rxor_set_region(desc,
3676 				cursor->addr_count,
3677 				DMA_RXOR125 << DMA_CUED_REGION_OFF);
3678 			if (index == src_cnt-1) {
3679 				ppc440spe_adma_dma2rxor_inc_addr(
3680 					desc, cursor, index, src_cnt);
3681 			}
3682 		} else {
3683 			cursor->state = 0;
3684 			cursor->xor_count = 1;
3685 			cursor->addrl = addr;
3686 			ppc440spe_rxor_set_region(desc,
3687 				cursor->addr_count,
3688 				DMA_RXOR12 << DMA_CUED_REGION_OFF);
3689 			ppc440spe_adma_dma2rxor_inc_addr(
3690 				desc, cursor, index, src_cnt);
3691 		}
3692 		break;
3693 	case 2:
3694 		cursor->state = 0;
3695 		cursor->addrl = addr;
3696 		cursor->xor_count++;
3697 		if (index) {
3698 			ppc440spe_adma_dma2rxor_inc_addr(
3699 				desc, cursor, index, src_cnt);
3700 		}
3701 		break;
3702 	}
3703 
3704 	return rval;
3705 }
3706 
3707 /**
3708  * ppc440spe_adma_dma2rxor_set_src - set RXOR source address; it's assumed that
3709  *	ppc440spe_adma_dma2rxor_prep_src() has already done prior this call
3710  */
3711 static void ppc440spe_adma_dma2rxor_set_src(
3712 		struct ppc440spe_adma_desc_slot *desc,
3713 		int index, dma_addr_t addr)
3714 {
3715 	struct xor_cb *xcb = desc->hw_desc;
3716 	int k = 0, op = 0, lop = 0;
3717 
3718 	/* get the RXOR operand which corresponds to index addr */
3719 	while (op <= index) {
3720 		lop = op;
3721 		if (k == XOR_MAX_OPS) {
3722 			k = 0;
3723 			desc = list_entry(desc->chain_node.next,
3724 				struct ppc440spe_adma_desc_slot, chain_node);
3725 			xcb = desc->hw_desc;
3726 
3727 		}
3728 		if ((xcb->ops[k++].h & (DMA_RXOR12 << DMA_CUED_REGION_OFF)) ==
3729 		    (DMA_RXOR12 << DMA_CUED_REGION_OFF))
3730 			op += 2;
3731 		else
3732 			op += 3;
3733 	}
3734 
3735 	BUG_ON(k < 1);
3736 
3737 	if (test_bit(k-1, desc->reverse_flags)) {
3738 		/* reverse operand order; put last op in RXOR group */
3739 		if (index == op - 1)
3740 			ppc440spe_rxor_set_src(desc, k - 1, addr);
3741 	} else {
3742 		/* direct operand order; put first op in RXOR group */
3743 		if (index == lop)
3744 			ppc440spe_rxor_set_src(desc, k - 1, addr);
3745 	}
3746 }
3747 
3748 /**
3749  * ppc440spe_adma_dma2rxor_set_mult - set RXOR multipliers; it's assumed that
3750  *	ppc440spe_adma_dma2rxor_prep_src() has already done prior this call
3751  */
3752 static void ppc440spe_adma_dma2rxor_set_mult(
3753 		struct ppc440spe_adma_desc_slot *desc,
3754 		int index, u8 mult)
3755 {
3756 	struct xor_cb *xcb = desc->hw_desc;
3757 	int k = 0, op = 0, lop = 0;
3758 
3759 	/* get the RXOR operand which corresponds to index mult */
3760 	while (op <= index) {
3761 		lop = op;
3762 		if (k == XOR_MAX_OPS) {
3763 			k = 0;
3764 			desc = list_entry(desc->chain_node.next,
3765 					  struct ppc440spe_adma_desc_slot,
3766 					  chain_node);
3767 			xcb = desc->hw_desc;
3768 
3769 		}
3770 		if ((xcb->ops[k++].h & (DMA_RXOR12 << DMA_CUED_REGION_OFF)) ==
3771 		    (DMA_RXOR12 << DMA_CUED_REGION_OFF))
3772 			op += 2;
3773 		else
3774 			op += 3;
3775 	}
3776 
3777 	BUG_ON(k < 1);
3778 	if (test_bit(k-1, desc->reverse_flags)) {
3779 		/* reverse order */
3780 		ppc440spe_rxor_set_mult(desc, k - 1, op - index - 1, mult);
3781 	} else {
3782 		/* direct order */
3783 		ppc440spe_rxor_set_mult(desc, k - 1, index - lop, mult);
3784 	}
3785 }
3786 
3787 /**
3788  * ppc440spe_init_rxor_cursor -
3789  */
3790 static void ppc440spe_init_rxor_cursor(struct ppc440spe_rxor *cursor)
3791 {
3792 	memset(cursor, 0, sizeof(struct ppc440spe_rxor));
3793 	cursor->state = 2;
3794 }
3795 
3796 /**
3797  * ppc440spe_adma_pq_set_src_mult - set multiplication coefficient into
3798  * descriptor for the PQXOR operation
3799  */
3800 static void ppc440spe_adma_pq_set_src_mult(
3801 		struct ppc440spe_adma_desc_slot *sw_desc,
3802 		unsigned char mult, int index, int dst_pos)
3803 {
3804 	struct ppc440spe_adma_chan *chan;
3805 	u32 mult_idx, mult_dst;
3806 	struct ppc440spe_adma_desc_slot *iter = NULL, *iter1 = NULL;
3807 
3808 	chan = to_ppc440spe_adma_chan(sw_desc->async_tx.chan);
3809 
3810 	switch (chan->device->id) {
3811 	case PPC440SPE_DMA0_ID:
3812 	case PPC440SPE_DMA1_ID:
3813 		if (test_bit(PPC440SPE_DESC_RXOR, &sw_desc->flags)) {
3814 			int region = test_bit(PPC440SPE_DESC_RXOR12,
3815 					&sw_desc->flags) ? 2 : 3;
3816 
3817 			if (index < region) {
3818 				/* RXOR multipliers */
3819 				iter = ppc440spe_get_group_entry(sw_desc,
3820 					sw_desc->dst_cnt - 1);
3821 				if (sw_desc->dst_cnt == 2)
3822 					iter1 = ppc440spe_get_group_entry(
3823 							sw_desc, 0);
3824 
3825 				mult_idx = DMA_CUED_MULT1_OFF + (index << 3);
3826 				mult_dst = DMA_CDB_SG_SRC;
3827 			} else {
3828 				/* WXOR multiplier */
3829 				iter = ppc440spe_get_group_entry(sw_desc,
3830 							index - region +
3831 							sw_desc->dst_cnt);
3832 				mult_idx = DMA_CUED_MULT1_OFF;
3833 				mult_dst = dst_pos ? DMA_CDB_SG_DST2 :
3834 						     DMA_CDB_SG_DST1;
3835 			}
3836 		} else {
3837 			int znum = 0;
3838 
3839 			/* WXOR-only;
3840 			 * skip first slots with destinations (if ZERO_DST has
3841 			 * place)
3842 			 */
3843 			if (test_bit(PPC440SPE_ZERO_P, &sw_desc->flags))
3844 				znum++;
3845 			if (test_bit(PPC440SPE_ZERO_Q, &sw_desc->flags))
3846 				znum++;
3847 
3848 			iter = ppc440spe_get_group_entry(sw_desc, index + znum);
3849 			mult_idx = DMA_CUED_MULT1_OFF;
3850 			mult_dst = dst_pos ? DMA_CDB_SG_DST2 : DMA_CDB_SG_DST1;
3851 		}
3852 
3853 		if (likely(iter)) {
3854 			ppc440spe_desc_set_src_mult(iter, chan,
3855 				mult_idx, mult_dst, mult);
3856 
3857 			if (unlikely(iter1)) {
3858 				/* if we have two destinations for RXOR, then
3859 				 * we've just set Q mult. Set-up P now.
3860 				 */
3861 				ppc440spe_desc_set_src_mult(iter1, chan,
3862 					mult_idx, mult_dst, 1);
3863 			}
3864 
3865 		}
3866 		break;
3867 
3868 	case PPC440SPE_XOR_ID:
3869 		iter = sw_desc->group_head;
3870 		if (sw_desc->dst_cnt == 2) {
3871 			/* both P & Q calculations required; set P mult here */
3872 			ppc440spe_adma_dma2rxor_set_mult(iter, index, 1);
3873 
3874 			/* and then set Q mult */
3875 			iter = ppc440spe_get_group_entry(sw_desc,
3876 			       sw_desc->descs_per_op);
3877 		}
3878 		ppc440spe_adma_dma2rxor_set_mult(iter, index, mult);
3879 		break;
3880 	}
3881 }
3882 
3883 /**
3884  * ppc440spe_adma_free_chan_resources - free the resources allocated
3885  */
3886 static void ppc440spe_adma_free_chan_resources(struct dma_chan *chan)
3887 {
3888 	struct ppc440spe_adma_chan *ppc440spe_chan;
3889 	struct ppc440spe_adma_desc_slot *iter, *_iter;
3890 	int in_use_descs = 0;
3891 
3892 	ppc440spe_chan = to_ppc440spe_adma_chan(chan);
3893 	ppc440spe_adma_slot_cleanup(ppc440spe_chan);
3894 
3895 	spin_lock_bh(&ppc440spe_chan->lock);
3896 	list_for_each_entry_safe(iter, _iter, &ppc440spe_chan->chain,
3897 					chain_node) {
3898 		in_use_descs++;
3899 		list_del(&iter->chain_node);
3900 	}
3901 	list_for_each_entry_safe_reverse(iter, _iter,
3902 			&ppc440spe_chan->all_slots, slot_node) {
3903 		list_del(&iter->slot_node);
3904 		kfree(iter);
3905 		ppc440spe_chan->slots_allocated--;
3906 	}
3907 	ppc440spe_chan->last_used = NULL;
3908 
3909 	dev_dbg(ppc440spe_chan->device->common.dev,
3910 		"ppc440spe adma%d %s slots_allocated %d\n",
3911 		ppc440spe_chan->device->id,
3912 		__func__, ppc440spe_chan->slots_allocated);
3913 	spin_unlock_bh(&ppc440spe_chan->lock);
3914 
3915 	/* one is ok since we left it on there on purpose */
3916 	if (in_use_descs > 1)
3917 		printk(KERN_ERR "SPE: Freeing %d in use descriptors!\n",
3918 			in_use_descs - 1);
3919 }
3920 
3921 /**
3922  * ppc440spe_adma_tx_status - poll the status of an ADMA transaction
3923  * @chan: ADMA channel handle
3924  * @cookie: ADMA transaction identifier
3925  * @txstate: a holder for the current state of the channel
3926  */
3927 static enum dma_status ppc440spe_adma_tx_status(struct dma_chan *chan,
3928 			dma_cookie_t cookie, struct dma_tx_state *txstate)
3929 {
3930 	struct ppc440spe_adma_chan *ppc440spe_chan;
3931 	enum dma_status ret;
3932 
3933 	ppc440spe_chan = to_ppc440spe_adma_chan(chan);
3934 	ret = dma_cookie_status(chan, cookie, txstate);
3935 	if (ret == DMA_SUCCESS)
3936 		return ret;
3937 
3938 	ppc440spe_adma_slot_cleanup(ppc440spe_chan);
3939 
3940 	return dma_cookie_status(chan, cookie, txstate);
3941 }
3942 
3943 /**
3944  * ppc440spe_adma_eot_handler - end of transfer interrupt handler
3945  */
3946 static irqreturn_t ppc440spe_adma_eot_handler(int irq, void *data)
3947 {
3948 	struct ppc440spe_adma_chan *chan = data;
3949 
3950 	dev_dbg(chan->device->common.dev,
3951 		"ppc440spe adma%d: %s\n", chan->device->id, __func__);
3952 
3953 	tasklet_schedule(&chan->irq_tasklet);
3954 	ppc440spe_adma_device_clear_eot_status(chan);
3955 
3956 	return IRQ_HANDLED;
3957 }
3958 
3959 /**
3960  * ppc440spe_adma_err_handler - DMA error interrupt handler;
3961  *	do the same things as a eot handler
3962  */
3963 static irqreturn_t ppc440spe_adma_err_handler(int irq, void *data)
3964 {
3965 	struct ppc440spe_adma_chan *chan = data;
3966 
3967 	dev_dbg(chan->device->common.dev,
3968 		"ppc440spe adma%d: %s\n", chan->device->id, __func__);
3969 
3970 	tasklet_schedule(&chan->irq_tasklet);
3971 	ppc440spe_adma_device_clear_eot_status(chan);
3972 
3973 	return IRQ_HANDLED;
3974 }
3975 
3976 /**
3977  * ppc440spe_test_callback - called when test operation has been done
3978  */
3979 static void ppc440spe_test_callback(void *unused)
3980 {
3981 	complete(&ppc440spe_r6_test_comp);
3982 }
3983 
3984 /**
3985  * ppc440spe_adma_issue_pending - flush all pending descriptors to h/w
3986  */
3987 static void ppc440spe_adma_issue_pending(struct dma_chan *chan)
3988 {
3989 	struct ppc440spe_adma_chan *ppc440spe_chan;
3990 
3991 	ppc440spe_chan = to_ppc440spe_adma_chan(chan);
3992 	dev_dbg(ppc440spe_chan->device->common.dev,
3993 		"ppc440spe adma%d: %s %d \n", ppc440spe_chan->device->id,
3994 		__func__, ppc440spe_chan->pending);
3995 
3996 	if (ppc440spe_chan->pending) {
3997 		ppc440spe_chan->pending = 0;
3998 		ppc440spe_chan_append(ppc440spe_chan);
3999 	}
4000 }
4001 
4002 /**
4003  * ppc440spe_chan_start_null_xor - initiate the first XOR operation (DMA engines
4004  *	use FIFOs (as opposite to chains used in XOR) so this is a XOR
4005  *	specific operation)
4006  */
4007 static void ppc440spe_chan_start_null_xor(struct ppc440spe_adma_chan *chan)
4008 {
4009 	struct ppc440spe_adma_desc_slot *sw_desc, *group_start;
4010 	dma_cookie_t cookie;
4011 	int slot_cnt, slots_per_op;
4012 
4013 	dev_dbg(chan->device->common.dev,
4014 		"ppc440spe adma%d: %s\n", chan->device->id, __func__);
4015 
4016 	spin_lock_bh(&chan->lock);
4017 	slot_cnt = ppc440spe_chan_xor_slot_count(0, 2, &slots_per_op);
4018 	sw_desc = ppc440spe_adma_alloc_slots(chan, slot_cnt, slots_per_op);
4019 	if (sw_desc) {
4020 		group_start = sw_desc->group_head;
4021 		list_splice_init(&sw_desc->group_list, &chan->chain);
4022 		async_tx_ack(&sw_desc->async_tx);
4023 		ppc440spe_desc_init_null_xor(group_start);
4024 
4025 		cookie = dma_cookie_assign(&sw_desc->async_tx);
4026 
4027 		/* initialize the completed cookie to be less than
4028 		 * the most recently used cookie
4029 		 */
4030 		chan->common.completed_cookie = cookie - 1;
4031 
4032 		/* channel should not be busy */
4033 		BUG_ON(ppc440spe_chan_is_busy(chan));
4034 
4035 		/* set the descriptor address */
4036 		ppc440spe_chan_set_first_xor_descriptor(chan, sw_desc);
4037 
4038 		/* run the descriptor */
4039 		ppc440spe_chan_run(chan);
4040 	} else
4041 		printk(KERN_ERR "ppc440spe adma%d"
4042 			" failed to allocate null descriptor\n",
4043 			chan->device->id);
4044 	spin_unlock_bh(&chan->lock);
4045 }
4046 
4047 /**
4048  * ppc440spe_test_raid6 - test are RAID-6 capabilities enabled successfully.
4049  *	For this we just perform one WXOR operation with the same source
4050  *	and destination addresses, the GF-multiplier is 1; so if RAID-6
4051  *	capabilities are enabled then we'll get src/dst filled with zero.
4052  */
4053 static int ppc440spe_test_raid6(struct ppc440spe_adma_chan *chan)
4054 {
4055 	struct ppc440spe_adma_desc_slot *sw_desc, *iter;
4056 	struct page *pg;
4057 	char *a;
4058 	dma_addr_t dma_addr, addrs[2];
4059 	unsigned long op = 0;
4060 	int rval = 0;
4061 
4062 	set_bit(PPC440SPE_DESC_WXOR, &op);
4063 
4064 	pg = alloc_page(GFP_KERNEL);
4065 	if (!pg)
4066 		return -ENOMEM;
4067 
4068 	spin_lock_bh(&chan->lock);
4069 	sw_desc = ppc440spe_adma_alloc_slots(chan, 1, 1);
4070 	if (sw_desc) {
4071 		/* 1 src, 1 dsr, int_ena, WXOR */
4072 		ppc440spe_desc_init_dma01pq(sw_desc, 1, 1, 1, op);
4073 		list_for_each_entry(iter, &sw_desc->group_list, chain_node) {
4074 			ppc440spe_desc_set_byte_count(iter, chan, PAGE_SIZE);
4075 			iter->unmap_len = PAGE_SIZE;
4076 		}
4077 	} else {
4078 		rval = -EFAULT;
4079 		spin_unlock_bh(&chan->lock);
4080 		goto exit;
4081 	}
4082 	spin_unlock_bh(&chan->lock);
4083 
4084 	/* Fill the test page with ones */
4085 	memset(page_address(pg), 0xFF, PAGE_SIZE);
4086 	dma_addr = dma_map_page(chan->device->dev, pg, 0,
4087 				PAGE_SIZE, DMA_BIDIRECTIONAL);
4088 
4089 	/* Setup addresses */
4090 	ppc440spe_adma_pq_set_src(sw_desc, dma_addr, 0);
4091 	ppc440spe_adma_pq_set_src_mult(sw_desc, 1, 0, 0);
4092 	addrs[0] = dma_addr;
4093 	addrs[1] = 0;
4094 	ppc440spe_adma_pq_set_dest(sw_desc, addrs, DMA_PREP_PQ_DISABLE_Q);
4095 
4096 	async_tx_ack(&sw_desc->async_tx);
4097 	sw_desc->async_tx.callback = ppc440spe_test_callback;
4098 	sw_desc->async_tx.callback_param = NULL;
4099 
4100 	init_completion(&ppc440spe_r6_test_comp);
4101 
4102 	ppc440spe_adma_tx_submit(&sw_desc->async_tx);
4103 	ppc440spe_adma_issue_pending(&chan->common);
4104 
4105 	wait_for_completion(&ppc440spe_r6_test_comp);
4106 
4107 	/* Now check if the test page is zeroed */
4108 	a = page_address(pg);
4109 	if ((*(u32 *)a) == 0 && memcmp(a, a+4, PAGE_SIZE-4) == 0) {
4110 		/* page is zero - RAID-6 enabled */
4111 		rval = 0;
4112 	} else {
4113 		/* RAID-6 was not enabled */
4114 		rval = -EINVAL;
4115 	}
4116 exit:
4117 	__free_page(pg);
4118 	return rval;
4119 }
4120 
4121 static void ppc440spe_adma_init_capabilities(struct ppc440spe_adma_device *adev)
4122 {
4123 	switch (adev->id) {
4124 	case PPC440SPE_DMA0_ID:
4125 	case PPC440SPE_DMA1_ID:
4126 		dma_cap_set(DMA_MEMCPY, adev->common.cap_mask);
4127 		dma_cap_set(DMA_INTERRUPT, adev->common.cap_mask);
4128 		dma_cap_set(DMA_MEMSET, adev->common.cap_mask);
4129 		dma_cap_set(DMA_PQ, adev->common.cap_mask);
4130 		dma_cap_set(DMA_PQ_VAL, adev->common.cap_mask);
4131 		dma_cap_set(DMA_XOR_VAL, adev->common.cap_mask);
4132 		break;
4133 	case PPC440SPE_XOR_ID:
4134 		dma_cap_set(DMA_XOR, adev->common.cap_mask);
4135 		dma_cap_set(DMA_PQ, adev->common.cap_mask);
4136 		dma_cap_set(DMA_INTERRUPT, adev->common.cap_mask);
4137 		adev->common.cap_mask = adev->common.cap_mask;
4138 		break;
4139 	}
4140 
4141 	/* Set base routines */
4142 	adev->common.device_alloc_chan_resources =
4143 				ppc440spe_adma_alloc_chan_resources;
4144 	adev->common.device_free_chan_resources =
4145 				ppc440spe_adma_free_chan_resources;
4146 	adev->common.device_tx_status = ppc440spe_adma_tx_status;
4147 	adev->common.device_issue_pending = ppc440spe_adma_issue_pending;
4148 
4149 	/* Set prep routines based on capability */
4150 	if (dma_has_cap(DMA_MEMCPY, adev->common.cap_mask)) {
4151 		adev->common.device_prep_dma_memcpy =
4152 			ppc440spe_adma_prep_dma_memcpy;
4153 	}
4154 	if (dma_has_cap(DMA_MEMSET, adev->common.cap_mask)) {
4155 		adev->common.device_prep_dma_memset =
4156 			ppc440spe_adma_prep_dma_memset;
4157 	}
4158 	if (dma_has_cap(DMA_XOR, adev->common.cap_mask)) {
4159 		adev->common.max_xor = XOR_MAX_OPS;
4160 		adev->common.device_prep_dma_xor =
4161 			ppc440spe_adma_prep_dma_xor;
4162 	}
4163 	if (dma_has_cap(DMA_PQ, adev->common.cap_mask)) {
4164 		switch (adev->id) {
4165 		case PPC440SPE_DMA0_ID:
4166 			dma_set_maxpq(&adev->common,
4167 				DMA0_FIFO_SIZE / sizeof(struct dma_cdb), 0);
4168 			break;
4169 		case PPC440SPE_DMA1_ID:
4170 			dma_set_maxpq(&adev->common,
4171 				DMA1_FIFO_SIZE / sizeof(struct dma_cdb), 0);
4172 			break;
4173 		case PPC440SPE_XOR_ID:
4174 			adev->common.max_pq = XOR_MAX_OPS * 3;
4175 			break;
4176 		}
4177 		adev->common.device_prep_dma_pq =
4178 			ppc440spe_adma_prep_dma_pq;
4179 	}
4180 	if (dma_has_cap(DMA_PQ_VAL, adev->common.cap_mask)) {
4181 		switch (adev->id) {
4182 		case PPC440SPE_DMA0_ID:
4183 			adev->common.max_pq = DMA0_FIFO_SIZE /
4184 						sizeof(struct dma_cdb);
4185 			break;
4186 		case PPC440SPE_DMA1_ID:
4187 			adev->common.max_pq = DMA1_FIFO_SIZE /
4188 						sizeof(struct dma_cdb);
4189 			break;
4190 		}
4191 		adev->common.device_prep_dma_pq_val =
4192 			ppc440spe_adma_prep_dma_pqzero_sum;
4193 	}
4194 	if (dma_has_cap(DMA_XOR_VAL, adev->common.cap_mask)) {
4195 		switch (adev->id) {
4196 		case PPC440SPE_DMA0_ID:
4197 			adev->common.max_xor = DMA0_FIFO_SIZE /
4198 						sizeof(struct dma_cdb);
4199 			break;
4200 		case PPC440SPE_DMA1_ID:
4201 			adev->common.max_xor = DMA1_FIFO_SIZE /
4202 						sizeof(struct dma_cdb);
4203 			break;
4204 		}
4205 		adev->common.device_prep_dma_xor_val =
4206 			ppc440spe_adma_prep_dma_xor_zero_sum;
4207 	}
4208 	if (dma_has_cap(DMA_INTERRUPT, adev->common.cap_mask)) {
4209 		adev->common.device_prep_dma_interrupt =
4210 			ppc440spe_adma_prep_dma_interrupt;
4211 	}
4212 	pr_info("%s: AMCC(R) PPC440SP(E) ADMA Engine: "
4213 	  "( %s%s%s%s%s%s%s)\n",
4214 	  dev_name(adev->dev),
4215 	  dma_has_cap(DMA_PQ, adev->common.cap_mask) ? "pq " : "",
4216 	  dma_has_cap(DMA_PQ_VAL, adev->common.cap_mask) ? "pq_val " : "",
4217 	  dma_has_cap(DMA_XOR, adev->common.cap_mask) ? "xor " : "",
4218 	  dma_has_cap(DMA_XOR_VAL, adev->common.cap_mask) ? "xor_val " : "",
4219 	  dma_has_cap(DMA_MEMCPY, adev->common.cap_mask) ? "memcpy " : "",
4220 	  dma_has_cap(DMA_MEMSET, adev->common.cap_mask)  ? "memset " : "",
4221 	  dma_has_cap(DMA_INTERRUPT, adev->common.cap_mask) ? "intr " : "");
4222 }
4223 
4224 static int ppc440spe_adma_setup_irqs(struct ppc440spe_adma_device *adev,
4225 				     struct ppc440spe_adma_chan *chan,
4226 				     int *initcode)
4227 {
4228 	struct platform_device *ofdev;
4229 	struct device_node *np;
4230 	int ret;
4231 
4232 	ofdev = container_of(adev->dev, struct platform_device, dev);
4233 	np = ofdev->dev.of_node;
4234 	if (adev->id != PPC440SPE_XOR_ID) {
4235 		adev->err_irq = irq_of_parse_and_map(np, 1);
4236 		if (adev->err_irq == NO_IRQ) {
4237 			dev_warn(adev->dev, "no err irq resource?\n");
4238 			*initcode = PPC_ADMA_INIT_IRQ2;
4239 			adev->err_irq = -ENXIO;
4240 		} else
4241 			atomic_inc(&ppc440spe_adma_err_irq_ref);
4242 	} else {
4243 		adev->err_irq = -ENXIO;
4244 	}
4245 
4246 	adev->irq = irq_of_parse_and_map(np, 0);
4247 	if (adev->irq == NO_IRQ) {
4248 		dev_err(adev->dev, "no irq resource\n");
4249 		*initcode = PPC_ADMA_INIT_IRQ1;
4250 		ret = -ENXIO;
4251 		goto err_irq_map;
4252 	}
4253 	dev_dbg(adev->dev, "irq %d, err irq %d\n",
4254 		adev->irq, adev->err_irq);
4255 
4256 	ret = request_irq(adev->irq, ppc440spe_adma_eot_handler,
4257 			  0, dev_driver_string(adev->dev), chan);
4258 	if (ret) {
4259 		dev_err(adev->dev, "can't request irq %d\n",
4260 			adev->irq);
4261 		*initcode = PPC_ADMA_INIT_IRQ1;
4262 		ret = -EIO;
4263 		goto err_req1;
4264 	}
4265 
4266 	/* only DMA engines have a separate error IRQ
4267 	 * so it's Ok if err_irq < 0 in XOR engine case.
4268 	 */
4269 	if (adev->err_irq > 0) {
4270 		/* both DMA engines share common error IRQ */
4271 		ret = request_irq(adev->err_irq,
4272 				  ppc440spe_adma_err_handler,
4273 				  IRQF_SHARED,
4274 				  dev_driver_string(adev->dev),
4275 				  chan);
4276 		if (ret) {
4277 			dev_err(adev->dev, "can't request irq %d\n",
4278 				adev->err_irq);
4279 			*initcode = PPC_ADMA_INIT_IRQ2;
4280 			ret = -EIO;
4281 			goto err_req2;
4282 		}
4283 	}
4284 
4285 	if (adev->id == PPC440SPE_XOR_ID) {
4286 		/* enable XOR engine interrupts */
4287 		iowrite32be(XOR_IE_CBCIE_BIT | XOR_IE_ICBIE_BIT |
4288 			    XOR_IE_ICIE_BIT | XOR_IE_RPTIE_BIT,
4289 			    &adev->xor_reg->ier);
4290 	} else {
4291 		u32 mask, enable;
4292 
4293 		np = of_find_compatible_node(NULL, NULL, "ibm,i2o-440spe");
4294 		if (!np) {
4295 			pr_err("%s: can't find I2O device tree node\n",
4296 				__func__);
4297 			ret = -ENODEV;
4298 			goto err_req2;
4299 		}
4300 		adev->i2o_reg = of_iomap(np, 0);
4301 		if (!adev->i2o_reg) {
4302 			pr_err("%s: failed to map I2O registers\n", __func__);
4303 			of_node_put(np);
4304 			ret = -EINVAL;
4305 			goto err_req2;
4306 		}
4307 		of_node_put(np);
4308 		/* Unmask 'CS FIFO Attention' interrupts and
4309 		 * enable generating interrupts on errors
4310 		 */
4311 		enable = (adev->id == PPC440SPE_DMA0_ID) ?
4312 			 ~(I2O_IOPIM_P0SNE | I2O_IOPIM_P0EM) :
4313 			 ~(I2O_IOPIM_P1SNE | I2O_IOPIM_P1EM);
4314 		mask = ioread32(&adev->i2o_reg->iopim) & enable;
4315 		iowrite32(mask, &adev->i2o_reg->iopim);
4316 	}
4317 	return 0;
4318 
4319 err_req2:
4320 	free_irq(adev->irq, chan);
4321 err_req1:
4322 	irq_dispose_mapping(adev->irq);
4323 err_irq_map:
4324 	if (adev->err_irq > 0) {
4325 		if (atomic_dec_and_test(&ppc440spe_adma_err_irq_ref))
4326 			irq_dispose_mapping(adev->err_irq);
4327 	}
4328 	return ret;
4329 }
4330 
4331 static void ppc440spe_adma_release_irqs(struct ppc440spe_adma_device *adev,
4332 					struct ppc440spe_adma_chan *chan)
4333 {
4334 	u32 mask, disable;
4335 
4336 	if (adev->id == PPC440SPE_XOR_ID) {
4337 		/* disable XOR engine interrupts */
4338 		mask = ioread32be(&adev->xor_reg->ier);
4339 		mask &= ~(XOR_IE_CBCIE_BIT | XOR_IE_ICBIE_BIT |
4340 			  XOR_IE_ICIE_BIT | XOR_IE_RPTIE_BIT);
4341 		iowrite32be(mask, &adev->xor_reg->ier);
4342 	} else {
4343 		/* disable DMAx engine interrupts */
4344 		disable = (adev->id == PPC440SPE_DMA0_ID) ?
4345 			  (I2O_IOPIM_P0SNE | I2O_IOPIM_P0EM) :
4346 			  (I2O_IOPIM_P1SNE | I2O_IOPIM_P1EM);
4347 		mask = ioread32(&adev->i2o_reg->iopim) | disable;
4348 		iowrite32(mask, &adev->i2o_reg->iopim);
4349 	}
4350 	free_irq(adev->irq, chan);
4351 	irq_dispose_mapping(adev->irq);
4352 	if (adev->err_irq > 0) {
4353 		free_irq(adev->err_irq, chan);
4354 		if (atomic_dec_and_test(&ppc440spe_adma_err_irq_ref)) {
4355 			irq_dispose_mapping(adev->err_irq);
4356 			iounmap(adev->i2o_reg);
4357 		}
4358 	}
4359 }
4360 
4361 /**
4362  * ppc440spe_adma_probe - probe the asynch device
4363  */
4364 static int ppc440spe_adma_probe(struct platform_device *ofdev)
4365 {
4366 	struct device_node *np = ofdev->dev.of_node;
4367 	struct resource res;
4368 	struct ppc440spe_adma_device *adev;
4369 	struct ppc440spe_adma_chan *chan;
4370 	struct ppc_dma_chan_ref *ref, *_ref;
4371 	int ret = 0, initcode = PPC_ADMA_INIT_OK;
4372 	const u32 *idx;
4373 	int len;
4374 	void *regs;
4375 	u32 id, pool_size;
4376 
4377 	if (of_device_is_compatible(np, "amcc,xor-accelerator")) {
4378 		id = PPC440SPE_XOR_ID;
4379 		/* As far as the XOR engine is concerned, it does not
4380 		 * use FIFOs but uses linked list. So there is no dependency
4381 		 * between pool size to allocate and the engine configuration.
4382 		 */
4383 		pool_size = PAGE_SIZE << 1;
4384 	} else {
4385 		/* it is DMA0 or DMA1 */
4386 		idx = of_get_property(np, "cell-index", &len);
4387 		if (!idx || (len != sizeof(u32))) {
4388 			dev_err(&ofdev->dev, "Device node %s has missing "
4389 				"or invalid cell-index property\n",
4390 				np->full_name);
4391 			return -EINVAL;
4392 		}
4393 		id = *idx;
4394 		/* DMA0,1 engines use FIFO to maintain CDBs, so we
4395 		 * should allocate the pool accordingly to size of this
4396 		 * FIFO. Thus, the pool size depends on the FIFO depth:
4397 		 * how much CDBs pointers the FIFO may contain then so
4398 		 * much CDBs we should provide in the pool.
4399 		 * That is
4400 		 *   CDB size = 32B;
4401 		 *   CDBs number = (DMA0_FIFO_SIZE >> 3);
4402 		 *   Pool size = CDBs number * CDB size =
4403 		 *      = (DMA0_FIFO_SIZE >> 3) << 5 = DMA0_FIFO_SIZE << 2.
4404 		 */
4405 		pool_size = (id == PPC440SPE_DMA0_ID) ?
4406 			    DMA0_FIFO_SIZE : DMA1_FIFO_SIZE;
4407 		pool_size <<= 2;
4408 	}
4409 
4410 	if (of_address_to_resource(np, 0, &res)) {
4411 		dev_err(&ofdev->dev, "failed to get memory resource\n");
4412 		initcode = PPC_ADMA_INIT_MEMRES;
4413 		ret = -ENODEV;
4414 		goto out;
4415 	}
4416 
4417 	if (!request_mem_region(res.start, resource_size(&res),
4418 				dev_driver_string(&ofdev->dev))) {
4419 		dev_err(&ofdev->dev, "failed to request memory region %pR\n",
4420 			&res);
4421 		initcode = PPC_ADMA_INIT_MEMREG;
4422 		ret = -EBUSY;
4423 		goto out;
4424 	}
4425 
4426 	/* create a device */
4427 	adev = kzalloc(sizeof(*adev), GFP_KERNEL);
4428 	if (!adev) {
4429 		dev_err(&ofdev->dev, "failed to allocate device\n");
4430 		initcode = PPC_ADMA_INIT_ALLOC;
4431 		ret = -ENOMEM;
4432 		goto err_adev_alloc;
4433 	}
4434 
4435 	adev->id = id;
4436 	adev->pool_size = pool_size;
4437 	/* allocate coherent memory for hardware descriptors */
4438 	adev->dma_desc_pool_virt = dma_alloc_coherent(&ofdev->dev,
4439 					adev->pool_size, &adev->dma_desc_pool,
4440 					GFP_KERNEL);
4441 	if (adev->dma_desc_pool_virt == NULL) {
4442 		dev_err(&ofdev->dev, "failed to allocate %d bytes of coherent "
4443 			"memory for hardware descriptors\n",
4444 			adev->pool_size);
4445 		initcode = PPC_ADMA_INIT_COHERENT;
4446 		ret = -ENOMEM;
4447 		goto err_dma_alloc;
4448 	}
4449 	dev_dbg(&ofdev->dev, "allocated descriptor pool virt 0x%p phys 0x%llx\n",
4450 		adev->dma_desc_pool_virt, (u64)adev->dma_desc_pool);
4451 
4452 	regs = ioremap(res.start, resource_size(&res));
4453 	if (!regs) {
4454 		dev_err(&ofdev->dev, "failed to ioremap regs!\n");
4455 		goto err_regs_alloc;
4456 	}
4457 
4458 	if (adev->id == PPC440SPE_XOR_ID) {
4459 		adev->xor_reg = regs;
4460 		/* Reset XOR */
4461 		iowrite32be(XOR_CRSR_XASR_BIT, &adev->xor_reg->crsr);
4462 		iowrite32be(XOR_CRSR_64BA_BIT, &adev->xor_reg->crrr);
4463 	} else {
4464 		size_t fifo_size = (adev->id == PPC440SPE_DMA0_ID) ?
4465 				   DMA0_FIFO_SIZE : DMA1_FIFO_SIZE;
4466 		adev->dma_reg = regs;
4467 		/* DMAx_FIFO_SIZE is defined in bytes,
4468 		 * <fsiz> - is defined in number of CDB pointers (8byte).
4469 		 * DMA FIFO Length = CSlength + CPlength, where
4470 		 * CSlength = CPlength = (fsiz + 1) * 8.
4471 		 */
4472 		iowrite32(DMA_FIFO_ENABLE | ((fifo_size >> 3) - 2),
4473 			  &adev->dma_reg->fsiz);
4474 		/* Configure DMA engine */
4475 		iowrite32(DMA_CFG_DXEPR_HP | DMA_CFG_DFMPP_HP | DMA_CFG_FALGN,
4476 			  &adev->dma_reg->cfg);
4477 		/* Clear Status */
4478 		iowrite32(~0, &adev->dma_reg->dsts);
4479 	}
4480 
4481 	adev->dev = &ofdev->dev;
4482 	adev->common.dev = &ofdev->dev;
4483 	INIT_LIST_HEAD(&adev->common.channels);
4484 	dev_set_drvdata(&ofdev->dev, adev);
4485 
4486 	/* create a channel */
4487 	chan = kzalloc(sizeof(*chan), GFP_KERNEL);
4488 	if (!chan) {
4489 		dev_err(&ofdev->dev, "can't allocate channel structure\n");
4490 		initcode = PPC_ADMA_INIT_CHANNEL;
4491 		ret = -ENOMEM;
4492 		goto err_chan_alloc;
4493 	}
4494 
4495 	spin_lock_init(&chan->lock);
4496 	INIT_LIST_HEAD(&chan->chain);
4497 	INIT_LIST_HEAD(&chan->all_slots);
4498 	chan->device = adev;
4499 	chan->common.device = &adev->common;
4500 	dma_cookie_init(&chan->common);
4501 	list_add_tail(&chan->common.device_node, &adev->common.channels);
4502 	tasklet_init(&chan->irq_tasklet, ppc440spe_adma_tasklet,
4503 		     (unsigned long)chan);
4504 
4505 	/* allocate and map helper pages for async validation or
4506 	 * async_mult/async_sum_product operations on DMA0/1.
4507 	 */
4508 	if (adev->id != PPC440SPE_XOR_ID) {
4509 		chan->pdest_page = alloc_page(GFP_KERNEL);
4510 		chan->qdest_page = alloc_page(GFP_KERNEL);
4511 		if (!chan->pdest_page ||
4512 		    !chan->qdest_page) {
4513 			if (chan->pdest_page)
4514 				__free_page(chan->pdest_page);
4515 			if (chan->qdest_page)
4516 				__free_page(chan->qdest_page);
4517 			ret = -ENOMEM;
4518 			goto err_page_alloc;
4519 		}
4520 		chan->pdest = dma_map_page(&ofdev->dev, chan->pdest_page, 0,
4521 					   PAGE_SIZE, DMA_BIDIRECTIONAL);
4522 		chan->qdest = dma_map_page(&ofdev->dev, chan->qdest_page, 0,
4523 					   PAGE_SIZE, DMA_BIDIRECTIONAL);
4524 	}
4525 
4526 	ref = kmalloc(sizeof(*ref), GFP_KERNEL);
4527 	if (ref) {
4528 		ref->chan = &chan->common;
4529 		INIT_LIST_HEAD(&ref->node);
4530 		list_add_tail(&ref->node, &ppc440spe_adma_chan_list);
4531 	} else {
4532 		dev_err(&ofdev->dev, "failed to allocate channel reference!\n");
4533 		ret = -ENOMEM;
4534 		goto err_ref_alloc;
4535 	}
4536 
4537 	ret = ppc440spe_adma_setup_irqs(adev, chan, &initcode);
4538 	if (ret)
4539 		goto err_irq;
4540 
4541 	ppc440spe_adma_init_capabilities(adev);
4542 
4543 	ret = dma_async_device_register(&adev->common);
4544 	if (ret) {
4545 		initcode = PPC_ADMA_INIT_REGISTER;
4546 		dev_err(&ofdev->dev, "failed to register dma device\n");
4547 		goto err_dev_reg;
4548 	}
4549 
4550 	goto out;
4551 
4552 err_dev_reg:
4553 	ppc440spe_adma_release_irqs(adev, chan);
4554 err_irq:
4555 	list_for_each_entry_safe(ref, _ref, &ppc440spe_adma_chan_list, node) {
4556 		if (chan == to_ppc440spe_adma_chan(ref->chan)) {
4557 			list_del(&ref->node);
4558 			kfree(ref);
4559 		}
4560 	}
4561 err_ref_alloc:
4562 	if (adev->id != PPC440SPE_XOR_ID) {
4563 		dma_unmap_page(&ofdev->dev, chan->pdest,
4564 			       PAGE_SIZE, DMA_BIDIRECTIONAL);
4565 		dma_unmap_page(&ofdev->dev, chan->qdest,
4566 			       PAGE_SIZE, DMA_BIDIRECTIONAL);
4567 		__free_page(chan->pdest_page);
4568 		__free_page(chan->qdest_page);
4569 	}
4570 err_page_alloc:
4571 	kfree(chan);
4572 err_chan_alloc:
4573 	if (adev->id == PPC440SPE_XOR_ID)
4574 		iounmap(adev->xor_reg);
4575 	else
4576 		iounmap(adev->dma_reg);
4577 err_regs_alloc:
4578 	dma_free_coherent(adev->dev, adev->pool_size,
4579 			  adev->dma_desc_pool_virt,
4580 			  adev->dma_desc_pool);
4581 err_dma_alloc:
4582 	kfree(adev);
4583 err_adev_alloc:
4584 	release_mem_region(res.start, resource_size(&res));
4585 out:
4586 	if (id < PPC440SPE_ADMA_ENGINES_NUM)
4587 		ppc440spe_adma_devices[id] = initcode;
4588 
4589 	return ret;
4590 }
4591 
4592 /**
4593  * ppc440spe_adma_remove - remove the asynch device
4594  */
4595 static int ppc440spe_adma_remove(struct platform_device *ofdev)
4596 {
4597 	struct ppc440spe_adma_device *adev = dev_get_drvdata(&ofdev->dev);
4598 	struct device_node *np = ofdev->dev.of_node;
4599 	struct resource res;
4600 	struct dma_chan *chan, *_chan;
4601 	struct ppc_dma_chan_ref *ref, *_ref;
4602 	struct ppc440spe_adma_chan *ppc440spe_chan;
4603 
4604 	dev_set_drvdata(&ofdev->dev, NULL);
4605 	if (adev->id < PPC440SPE_ADMA_ENGINES_NUM)
4606 		ppc440spe_adma_devices[adev->id] = -1;
4607 
4608 	dma_async_device_unregister(&adev->common);
4609 
4610 	list_for_each_entry_safe(chan, _chan, &adev->common.channels,
4611 				 device_node) {
4612 		ppc440spe_chan = to_ppc440spe_adma_chan(chan);
4613 		ppc440spe_adma_release_irqs(adev, ppc440spe_chan);
4614 		tasklet_kill(&ppc440spe_chan->irq_tasklet);
4615 		if (adev->id != PPC440SPE_XOR_ID) {
4616 			dma_unmap_page(&ofdev->dev, ppc440spe_chan->pdest,
4617 					PAGE_SIZE, DMA_BIDIRECTIONAL);
4618 			dma_unmap_page(&ofdev->dev, ppc440spe_chan->qdest,
4619 					PAGE_SIZE, DMA_BIDIRECTIONAL);
4620 			__free_page(ppc440spe_chan->pdest_page);
4621 			__free_page(ppc440spe_chan->qdest_page);
4622 		}
4623 		list_for_each_entry_safe(ref, _ref, &ppc440spe_adma_chan_list,
4624 					 node) {
4625 			if (ppc440spe_chan ==
4626 			    to_ppc440spe_adma_chan(ref->chan)) {
4627 				list_del(&ref->node);
4628 				kfree(ref);
4629 			}
4630 		}
4631 		list_del(&chan->device_node);
4632 		kfree(ppc440spe_chan);
4633 	}
4634 
4635 	dma_free_coherent(adev->dev, adev->pool_size,
4636 			  adev->dma_desc_pool_virt, adev->dma_desc_pool);
4637 	if (adev->id == PPC440SPE_XOR_ID)
4638 		iounmap(adev->xor_reg);
4639 	else
4640 		iounmap(adev->dma_reg);
4641 	of_address_to_resource(np, 0, &res);
4642 	release_mem_region(res.start, resource_size(&res));
4643 	kfree(adev);
4644 	return 0;
4645 }
4646 
4647 /*
4648  * /sys driver interface to enable h/w RAID-6 capabilities
4649  * Files created in e.g. /sys/devices/plb.0/400100100.dma0/driver/
4650  * directory are "devices", "enable" and "poly".
4651  * "devices" shows available engines.
4652  * "enable" is used to enable RAID-6 capabilities or to check
4653  * whether these has been activated.
4654  * "poly" allows setting/checking used polynomial (for PPC440SPe only).
4655  */
4656 
4657 static ssize_t show_ppc440spe_devices(struct device_driver *dev, char *buf)
4658 {
4659 	ssize_t size = 0;
4660 	int i;
4661 
4662 	for (i = 0; i < PPC440SPE_ADMA_ENGINES_NUM; i++) {
4663 		if (ppc440spe_adma_devices[i] == -1)
4664 			continue;
4665 		size += snprintf(buf + size, PAGE_SIZE - size,
4666 				 "PPC440SP(E)-ADMA.%d: %s\n", i,
4667 				 ppc_adma_errors[ppc440spe_adma_devices[i]]);
4668 	}
4669 	return size;
4670 }
4671 
4672 static ssize_t show_ppc440spe_r6enable(struct device_driver *dev, char *buf)
4673 {
4674 	return snprintf(buf, PAGE_SIZE,
4675 			"PPC440SP(e) RAID-6 capabilities are %sABLED.\n",
4676 			ppc440spe_r6_enabled ? "EN" : "DIS");
4677 }
4678 
4679 static ssize_t store_ppc440spe_r6enable(struct device_driver *dev,
4680 					const char *buf, size_t count)
4681 {
4682 	unsigned long val;
4683 
4684 	if (!count || count > 11)
4685 		return -EINVAL;
4686 
4687 	if (!ppc440spe_r6_tchan)
4688 		return -EFAULT;
4689 
4690 	/* Write a key */
4691 	sscanf(buf, "%lx", &val);
4692 	dcr_write(ppc440spe_mq_dcr_host, DCRN_MQ0_XORBA, val);
4693 	isync();
4694 
4695 	/* Verify whether it really works now */
4696 	if (ppc440spe_test_raid6(ppc440spe_r6_tchan) == 0) {
4697 		pr_info("PPC440SP(e) RAID-6 has been activated "
4698 			"successfully\n");
4699 		ppc440spe_r6_enabled = 1;
4700 	} else {
4701 		pr_info("PPC440SP(e) RAID-6 hasn't been activated!"
4702 			" Error key ?\n");
4703 		ppc440spe_r6_enabled = 0;
4704 	}
4705 	return count;
4706 }
4707 
4708 static ssize_t show_ppc440spe_r6poly(struct device_driver *dev, char *buf)
4709 {
4710 	ssize_t size = 0;
4711 	u32 reg;
4712 
4713 #ifdef CONFIG_440SP
4714 	/* 440SP has fixed polynomial */
4715 	reg = 0x4d;
4716 #else
4717 	reg = dcr_read(ppc440spe_mq_dcr_host, DCRN_MQ0_CFBHL);
4718 	reg >>= MQ0_CFBHL_POLY;
4719 	reg &= 0xFF;
4720 #endif
4721 
4722 	size = snprintf(buf, PAGE_SIZE, "PPC440SP(e) RAID-6 driver "
4723 			"uses 0x1%02x polynomial.\n", reg);
4724 	return size;
4725 }
4726 
4727 static ssize_t store_ppc440spe_r6poly(struct device_driver *dev,
4728 				      const char *buf, size_t count)
4729 {
4730 	unsigned long reg, val;
4731 
4732 #ifdef CONFIG_440SP
4733 	/* 440SP uses default 0x14D polynomial only */
4734 	return -EINVAL;
4735 #endif
4736 
4737 	if (!count || count > 6)
4738 		return -EINVAL;
4739 
4740 	/* e.g., 0x14D or 0x11D */
4741 	sscanf(buf, "%lx", &val);
4742 
4743 	if (val & ~0x1FF)
4744 		return -EINVAL;
4745 
4746 	val &= 0xFF;
4747 	reg = dcr_read(ppc440spe_mq_dcr_host, DCRN_MQ0_CFBHL);
4748 	reg &= ~(0xFF << MQ0_CFBHL_POLY);
4749 	reg |= val << MQ0_CFBHL_POLY;
4750 	dcr_write(ppc440spe_mq_dcr_host, DCRN_MQ0_CFBHL, reg);
4751 
4752 	return count;
4753 }
4754 
4755 static DRIVER_ATTR(devices, S_IRUGO, show_ppc440spe_devices, NULL);
4756 static DRIVER_ATTR(enable, S_IRUGO | S_IWUSR, show_ppc440spe_r6enable,
4757 		   store_ppc440spe_r6enable);
4758 static DRIVER_ATTR(poly, S_IRUGO | S_IWUSR, show_ppc440spe_r6poly,
4759 		   store_ppc440spe_r6poly);
4760 
4761 /*
4762  * Common initialisation for RAID engines; allocate memory for
4763  * DMAx FIFOs, perform configuration common for all DMA engines.
4764  * Further DMA engine specific configuration is done at probe time.
4765  */
4766 static int ppc440spe_configure_raid_devices(void)
4767 {
4768 	struct device_node *np;
4769 	struct resource i2o_res;
4770 	struct i2o_regs __iomem *i2o_reg;
4771 	dcr_host_t i2o_dcr_host;
4772 	unsigned int dcr_base, dcr_len;
4773 	int i, ret;
4774 
4775 	np = of_find_compatible_node(NULL, NULL, "ibm,i2o-440spe");
4776 	if (!np) {
4777 		pr_err("%s: can't find I2O device tree node\n",
4778 			__func__);
4779 		return -ENODEV;
4780 	}
4781 
4782 	if (of_address_to_resource(np, 0, &i2o_res)) {
4783 		of_node_put(np);
4784 		return -EINVAL;
4785 	}
4786 
4787 	i2o_reg = of_iomap(np, 0);
4788 	if (!i2o_reg) {
4789 		pr_err("%s: failed to map I2O registers\n", __func__);
4790 		of_node_put(np);
4791 		return -EINVAL;
4792 	}
4793 
4794 	/* Get I2O DCRs base */
4795 	dcr_base = dcr_resource_start(np, 0);
4796 	dcr_len = dcr_resource_len(np, 0);
4797 	if (!dcr_base && !dcr_len) {
4798 		pr_err("%s: can't get DCR registers base/len!\n",
4799 			np->full_name);
4800 		of_node_put(np);
4801 		iounmap(i2o_reg);
4802 		return -ENODEV;
4803 	}
4804 
4805 	i2o_dcr_host = dcr_map(np, dcr_base, dcr_len);
4806 	if (!DCR_MAP_OK(i2o_dcr_host)) {
4807 		pr_err("%s: failed to map DCRs!\n", np->full_name);
4808 		of_node_put(np);
4809 		iounmap(i2o_reg);
4810 		return -ENODEV;
4811 	}
4812 	of_node_put(np);
4813 
4814 	/* Provide memory regions for DMA's FIFOs: I2O, DMA0 and DMA1 share
4815 	 * the base address of FIFO memory space.
4816 	 * Actually we need twice more physical memory than programmed in the
4817 	 * <fsiz> register (because there are two FIFOs for each DMA: CP and CS)
4818 	 */
4819 	ppc440spe_dma_fifo_buf = kmalloc((DMA0_FIFO_SIZE + DMA1_FIFO_SIZE) << 1,
4820 					 GFP_KERNEL);
4821 	if (!ppc440spe_dma_fifo_buf) {
4822 		pr_err("%s: DMA FIFO buffer allocation failed.\n", __func__);
4823 		iounmap(i2o_reg);
4824 		dcr_unmap(i2o_dcr_host, dcr_len);
4825 		return -ENOMEM;
4826 	}
4827 
4828 	/*
4829 	 * Configure h/w
4830 	 */
4831 	/* Reset I2O/DMA */
4832 	mtdcri(SDR0, DCRN_SDR0_SRST, DCRN_SDR0_SRST_I2ODMA);
4833 	mtdcri(SDR0, DCRN_SDR0_SRST, 0);
4834 
4835 	/* Setup the base address of mmaped registers */
4836 	dcr_write(i2o_dcr_host, DCRN_I2O0_IBAH, (u32)(i2o_res.start >> 32));
4837 	dcr_write(i2o_dcr_host, DCRN_I2O0_IBAL, (u32)(i2o_res.start) |
4838 						I2O_REG_ENABLE);
4839 	dcr_unmap(i2o_dcr_host, dcr_len);
4840 
4841 	/* Setup FIFO memory space base address */
4842 	iowrite32(0, &i2o_reg->ifbah);
4843 	iowrite32(((u32)__pa(ppc440spe_dma_fifo_buf)), &i2o_reg->ifbal);
4844 
4845 	/* set zero FIFO size for I2O, so the whole
4846 	 * ppc440spe_dma_fifo_buf is used by DMAs.
4847 	 * DMAx_FIFOs will be configured while probe.
4848 	 */
4849 	iowrite32(0, &i2o_reg->ifsiz);
4850 	iounmap(i2o_reg);
4851 
4852 	/* To prepare WXOR/RXOR functionality we need access to
4853 	 * Memory Queue Module DCRs (finally it will be enabled
4854 	 * via /sys interface of the ppc440spe ADMA driver).
4855 	 */
4856 	np = of_find_compatible_node(NULL, NULL, "ibm,mq-440spe");
4857 	if (!np) {
4858 		pr_err("%s: can't find MQ device tree node\n",
4859 			__func__);
4860 		ret = -ENODEV;
4861 		goto out_free;
4862 	}
4863 
4864 	/* Get MQ DCRs base */
4865 	dcr_base = dcr_resource_start(np, 0);
4866 	dcr_len = dcr_resource_len(np, 0);
4867 	if (!dcr_base && !dcr_len) {
4868 		pr_err("%s: can't get DCR registers base/len!\n",
4869 			np->full_name);
4870 		ret = -ENODEV;
4871 		goto out_mq;
4872 	}
4873 
4874 	ppc440spe_mq_dcr_host = dcr_map(np, dcr_base, dcr_len);
4875 	if (!DCR_MAP_OK(ppc440spe_mq_dcr_host)) {
4876 		pr_err("%s: failed to map DCRs!\n", np->full_name);
4877 		ret = -ENODEV;
4878 		goto out_mq;
4879 	}
4880 	of_node_put(np);
4881 	ppc440spe_mq_dcr_len = dcr_len;
4882 
4883 	/* Set HB alias */
4884 	dcr_write(ppc440spe_mq_dcr_host, DCRN_MQ0_BAUH, DMA_CUED_XOR_HB);
4885 
4886 	/* Set:
4887 	 * - LL transaction passing limit to 1;
4888 	 * - Memory controller cycle limit to 1;
4889 	 * - Galois Polynomial to 0x14d (default)
4890 	 */
4891 	dcr_write(ppc440spe_mq_dcr_host, DCRN_MQ0_CFBHL,
4892 		  (1 << MQ0_CFBHL_TPLM) | (1 << MQ0_CFBHL_HBCL) |
4893 		  (PPC440SPE_DEFAULT_POLY << MQ0_CFBHL_POLY));
4894 
4895 	atomic_set(&ppc440spe_adma_err_irq_ref, 0);
4896 	for (i = 0; i < PPC440SPE_ADMA_ENGINES_NUM; i++)
4897 		ppc440spe_adma_devices[i] = -1;
4898 
4899 	return 0;
4900 
4901 out_mq:
4902 	of_node_put(np);
4903 out_free:
4904 	kfree(ppc440spe_dma_fifo_buf);
4905 	return ret;
4906 }
4907 
4908 static const struct of_device_id ppc440spe_adma_of_match[] = {
4909 	{ .compatible	= "ibm,dma-440spe", },
4910 	{ .compatible	= "amcc,xor-accelerator", },
4911 	{},
4912 };
4913 MODULE_DEVICE_TABLE(of, ppc440spe_adma_of_match);
4914 
4915 static struct platform_driver ppc440spe_adma_driver = {
4916 	.probe = ppc440spe_adma_probe,
4917 	.remove = ppc440spe_adma_remove,
4918 	.driver = {
4919 		.name = "PPC440SP(E)-ADMA",
4920 		.owner = THIS_MODULE,
4921 		.of_match_table = ppc440spe_adma_of_match,
4922 	},
4923 };
4924 
4925 static __init int ppc440spe_adma_init(void)
4926 {
4927 	int ret;
4928 
4929 	ret = ppc440spe_configure_raid_devices();
4930 	if (ret)
4931 		return ret;
4932 
4933 	ret = platform_driver_register(&ppc440spe_adma_driver);
4934 	if (ret) {
4935 		pr_err("%s: failed to register platform driver\n",
4936 			__func__);
4937 		goto out_reg;
4938 	}
4939 
4940 	/* Initialization status */
4941 	ret = driver_create_file(&ppc440spe_adma_driver.driver,
4942 				 &driver_attr_devices);
4943 	if (ret)
4944 		goto out_dev;
4945 
4946 	/* RAID-6 h/w enable entry */
4947 	ret = driver_create_file(&ppc440spe_adma_driver.driver,
4948 				 &driver_attr_enable);
4949 	if (ret)
4950 		goto out_en;
4951 
4952 	/* GF polynomial to use */
4953 	ret = driver_create_file(&ppc440spe_adma_driver.driver,
4954 				 &driver_attr_poly);
4955 	if (!ret)
4956 		return ret;
4957 
4958 	driver_remove_file(&ppc440spe_adma_driver.driver,
4959 			   &driver_attr_enable);
4960 out_en:
4961 	driver_remove_file(&ppc440spe_adma_driver.driver,
4962 			   &driver_attr_devices);
4963 out_dev:
4964 	/* User will not be able to enable h/w RAID-6 */
4965 	pr_err("%s: failed to create RAID-6 driver interface\n",
4966 		__func__);
4967 	platform_driver_unregister(&ppc440spe_adma_driver);
4968 out_reg:
4969 	dcr_unmap(ppc440spe_mq_dcr_host, ppc440spe_mq_dcr_len);
4970 	kfree(ppc440spe_dma_fifo_buf);
4971 	return ret;
4972 }
4973 
4974 static void __exit ppc440spe_adma_exit(void)
4975 {
4976 	driver_remove_file(&ppc440spe_adma_driver.driver,
4977 			   &driver_attr_poly);
4978 	driver_remove_file(&ppc440spe_adma_driver.driver,
4979 			   &driver_attr_enable);
4980 	driver_remove_file(&ppc440spe_adma_driver.driver,
4981 			   &driver_attr_devices);
4982 	platform_driver_unregister(&ppc440spe_adma_driver);
4983 	dcr_unmap(ppc440spe_mq_dcr_host, ppc440spe_mq_dcr_len);
4984 	kfree(ppc440spe_dma_fifo_buf);
4985 }
4986 
4987 arch_initcall(ppc440spe_adma_init);
4988 module_exit(ppc440spe_adma_exit);
4989 
4990 MODULE_AUTHOR("Yuri Tikhonov <yur@emcraft.com>");
4991 MODULE_DESCRIPTION("PPC440SPE ADMA Engine Driver");
4992 MODULE_LICENSE("GPL");
4993