xref: /openbmc/linux/drivers/dma/ppc4xx/adma.c (revision bc000245)
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_address.h>
46 #include <linux/of_irq.h>
47 #include <linux/of_platform.h>
48 #include <asm/dcr.h>
49 #include <asm/dcr-regs.h>
50 #include "adma.h"
51 #include "../dmaengine.h"
52 
53 enum ppc_adma_init_code {
54 	PPC_ADMA_INIT_OK = 0,
55 	PPC_ADMA_INIT_MEMRES,
56 	PPC_ADMA_INIT_MEMREG,
57 	PPC_ADMA_INIT_ALLOC,
58 	PPC_ADMA_INIT_COHERENT,
59 	PPC_ADMA_INIT_CHANNEL,
60 	PPC_ADMA_INIT_IRQ1,
61 	PPC_ADMA_INIT_IRQ2,
62 	PPC_ADMA_INIT_REGISTER
63 };
64 
65 static char *ppc_adma_errors[] = {
66 	[PPC_ADMA_INIT_OK] = "ok",
67 	[PPC_ADMA_INIT_MEMRES] = "failed to get memory resource",
68 	[PPC_ADMA_INIT_MEMREG] = "failed to request memory region",
69 	[PPC_ADMA_INIT_ALLOC] = "failed to allocate memory for adev "
70 				"structure",
71 	[PPC_ADMA_INIT_COHERENT] = "failed to allocate coherent memory for "
72 				   "hardware descriptors",
73 	[PPC_ADMA_INIT_CHANNEL] = "failed to allocate memory for channel",
74 	[PPC_ADMA_INIT_IRQ1] = "failed to request first irq",
75 	[PPC_ADMA_INIT_IRQ2] = "failed to request second irq",
76 	[PPC_ADMA_INIT_REGISTER] = "failed to register dma async device",
77 };
78 
79 static enum ppc_adma_init_code
80 ppc440spe_adma_devices[PPC440SPE_ADMA_ENGINES_NUM];
81 
82 struct ppc_dma_chan_ref {
83 	struct dma_chan *chan;
84 	struct list_head node;
85 };
86 
87 /* The list of channels exported by ppc440spe ADMA */
88 struct list_head
89 ppc440spe_adma_chan_list = LIST_HEAD_INIT(ppc440spe_adma_chan_list);
90 
91 /* This flag is set when want to refetch the xor chain in the interrupt
92  * handler
93  */
94 static u32 do_xor_refetch;
95 
96 /* Pointer to DMA0, DMA1 CP/CS FIFO */
97 static void *ppc440spe_dma_fifo_buf;
98 
99 /* Pointers to last submitted to DMA0, DMA1 CDBs */
100 static struct ppc440spe_adma_desc_slot *chan_last_sub[3];
101 static struct ppc440spe_adma_desc_slot *chan_first_cdb[3];
102 
103 /* Pointer to last linked and submitted xor CB */
104 static struct ppc440spe_adma_desc_slot *xor_last_linked;
105 static struct ppc440spe_adma_desc_slot *xor_last_submit;
106 
107 /* This array is used in data-check operations for storing a pattern */
108 static char ppc440spe_qword[16];
109 
110 static atomic_t ppc440spe_adma_err_irq_ref;
111 static dcr_host_t ppc440spe_mq_dcr_host;
112 static unsigned int ppc440spe_mq_dcr_len;
113 
114 /* Since RXOR operations use the common register (MQ0_CF2H) for setting-up
115  * the block size in transactions, then we do not allow to activate more than
116  * only one RXOR transactions simultaneously. So use this var to store
117  * the information about is RXOR currently active (PPC440SPE_RXOR_RUN bit is
118  * set) or not (PPC440SPE_RXOR_RUN is clear).
119  */
120 static unsigned long ppc440spe_rxor_state;
121 
122 /* These are used in enable & check routines
123  */
124 static u32 ppc440spe_r6_enabled;
125 static struct ppc440spe_adma_chan *ppc440spe_r6_tchan;
126 static struct completion ppc440spe_r6_test_comp;
127 
128 static int ppc440spe_adma_dma2rxor_prep_src(
129 		struct ppc440spe_adma_desc_slot *desc,
130 		struct ppc440spe_rxor *cursor, int index,
131 		int src_cnt, u32 addr);
132 static void ppc440spe_adma_dma2rxor_set_src(
133 		struct ppc440spe_adma_desc_slot *desc,
134 		int index, dma_addr_t addr);
135 static void ppc440spe_adma_dma2rxor_set_mult(
136 		struct ppc440spe_adma_desc_slot *desc,
137 		int index, u8 mult);
138 
139 #ifdef ADMA_LL_DEBUG
140 #define ADMA_LL_DBG(x) ({ if (1) x; 0; })
141 #else
142 #define ADMA_LL_DBG(x) ({ if (0) x; 0; })
143 #endif
144 
145 static void print_cb(struct ppc440spe_adma_chan *chan, void *block)
146 {
147 	struct dma_cdb *cdb;
148 	struct xor_cb *cb;
149 	int i;
150 
151 	switch (chan->device->id) {
152 	case 0:
153 	case 1:
154 		cdb = block;
155 
156 		pr_debug("CDB at %p [%d]:\n"
157 			"\t attr 0x%02x opc 0x%02x cnt 0x%08x\n"
158 			"\t sg1u 0x%08x sg1l 0x%08x\n"
159 			"\t sg2u 0x%08x sg2l 0x%08x\n"
160 			"\t sg3u 0x%08x sg3l 0x%08x\n",
161 			cdb, chan->device->id,
162 			cdb->attr, cdb->opc, le32_to_cpu(cdb->cnt),
163 			le32_to_cpu(cdb->sg1u), le32_to_cpu(cdb->sg1l),
164 			le32_to_cpu(cdb->sg2u), le32_to_cpu(cdb->sg2l),
165 			le32_to_cpu(cdb->sg3u), le32_to_cpu(cdb->sg3l)
166 		);
167 		break;
168 	case 2:
169 		cb = block;
170 
171 		pr_debug("CB at %p [%d]:\n"
172 			"\t cbc 0x%08x cbbc 0x%08x cbs 0x%08x\n"
173 			"\t cbtah 0x%08x cbtal 0x%08x\n"
174 			"\t cblah 0x%08x cblal 0x%08x\n",
175 			cb, chan->device->id,
176 			cb->cbc, cb->cbbc, cb->cbs,
177 			cb->cbtah, cb->cbtal,
178 			cb->cblah, cb->cblal);
179 		for (i = 0; i < 16; i++) {
180 			if (i && !cb->ops[i].h && !cb->ops[i].l)
181 				continue;
182 			pr_debug("\t ops[%2d]: h 0x%08x l 0x%08x\n",
183 				i, cb->ops[i].h, cb->ops[i].l);
184 		}
185 		break;
186 	}
187 }
188 
189 static void print_cb_list(struct ppc440spe_adma_chan *chan,
190 			  struct ppc440spe_adma_desc_slot *iter)
191 {
192 	for (; iter; iter = iter->hw_next)
193 		print_cb(chan, iter->hw_desc);
194 }
195 
196 static void prep_dma_xor_dbg(int id, dma_addr_t dst, dma_addr_t *src,
197 			     unsigned int src_cnt)
198 {
199 	int i;
200 
201 	pr_debug("\n%s(%d):\nsrc: ", __func__, id);
202 	for (i = 0; i < src_cnt; i++)
203 		pr_debug("\t0x%016llx ", src[i]);
204 	pr_debug("dst:\n\t0x%016llx\n", dst);
205 }
206 
207 static void prep_dma_pq_dbg(int id, dma_addr_t *dst, dma_addr_t *src,
208 			    unsigned int src_cnt)
209 {
210 	int i;
211 
212 	pr_debug("\n%s(%d):\nsrc: ", __func__, id);
213 	for (i = 0; i < src_cnt; i++)
214 		pr_debug("\t0x%016llx ", src[i]);
215 	pr_debug("dst: ");
216 	for (i = 0; i < 2; i++)
217 		pr_debug("\t0x%016llx ", dst[i]);
218 }
219 
220 static void prep_dma_pqzero_sum_dbg(int id, dma_addr_t *src,
221 				    unsigned int src_cnt,
222 				    const unsigned char *scf)
223 {
224 	int i;
225 
226 	pr_debug("\n%s(%d):\nsrc(coef): ", __func__, id);
227 	if (scf) {
228 		for (i = 0; i < src_cnt; i++)
229 			pr_debug("\t0x%016llx(0x%02x) ", src[i], scf[i]);
230 	} else {
231 		for (i = 0; i < src_cnt; i++)
232 			pr_debug("\t0x%016llx(no) ", src[i]);
233 	}
234 
235 	pr_debug("dst: ");
236 	for (i = 0; i < 2; i++)
237 		pr_debug("\t0x%016llx ", src[src_cnt + i]);
238 }
239 
240 /******************************************************************************
241  * Command (Descriptor) Blocks low-level routines
242  ******************************************************************************/
243 /**
244  * ppc440spe_desc_init_interrupt - initialize the descriptor for INTERRUPT
245  * pseudo operation
246  */
247 static void ppc440spe_desc_init_interrupt(struct ppc440spe_adma_desc_slot *desc,
248 					  struct ppc440spe_adma_chan *chan)
249 {
250 	struct xor_cb *p;
251 
252 	switch (chan->device->id) {
253 	case PPC440SPE_XOR_ID:
254 		p = desc->hw_desc;
255 		memset(desc->hw_desc, 0, sizeof(struct xor_cb));
256 		/* NOP with Command Block Complete Enable */
257 		p->cbc = XOR_CBCR_CBCE_BIT;
258 		break;
259 	case PPC440SPE_DMA0_ID:
260 	case PPC440SPE_DMA1_ID:
261 		memset(desc->hw_desc, 0, sizeof(struct dma_cdb));
262 		/* NOP with interrupt */
263 		set_bit(PPC440SPE_DESC_INT, &desc->flags);
264 		break;
265 	default:
266 		printk(KERN_ERR "Unsupported id %d in %s\n", chan->device->id,
267 				__func__);
268 		break;
269 	}
270 }
271 
272 /**
273  * ppc440spe_desc_init_null_xor - initialize the descriptor for NULL XOR
274  * pseudo operation
275  */
276 static void ppc440spe_desc_init_null_xor(struct ppc440spe_adma_desc_slot *desc)
277 {
278 	memset(desc->hw_desc, 0, sizeof(struct xor_cb));
279 	desc->hw_next = NULL;
280 	desc->src_cnt = 0;
281 	desc->dst_cnt = 1;
282 }
283 
284 /**
285  * ppc440spe_desc_init_xor - initialize the descriptor for XOR operation
286  */
287 static void ppc440spe_desc_init_xor(struct ppc440spe_adma_desc_slot *desc,
288 					 int src_cnt, unsigned long flags)
289 {
290 	struct xor_cb *hw_desc = desc->hw_desc;
291 
292 	memset(desc->hw_desc, 0, sizeof(struct xor_cb));
293 	desc->hw_next = NULL;
294 	desc->src_cnt = src_cnt;
295 	desc->dst_cnt = 1;
296 
297 	hw_desc->cbc = XOR_CBCR_TGT_BIT | src_cnt;
298 	if (flags & DMA_PREP_INTERRUPT)
299 		/* Enable interrupt on completion */
300 		hw_desc->cbc |= XOR_CBCR_CBCE_BIT;
301 }
302 
303 /**
304  * ppc440spe_desc_init_dma2pq - initialize the descriptor for PQ
305  * operation in DMA2 controller
306  */
307 static void ppc440spe_desc_init_dma2pq(struct ppc440spe_adma_desc_slot *desc,
308 		int dst_cnt, int src_cnt, unsigned long flags)
309 {
310 	struct xor_cb *hw_desc = desc->hw_desc;
311 
312 	memset(desc->hw_desc, 0, sizeof(struct xor_cb));
313 	desc->hw_next = NULL;
314 	desc->src_cnt = src_cnt;
315 	desc->dst_cnt = dst_cnt;
316 	memset(desc->reverse_flags, 0, sizeof(desc->reverse_flags));
317 	desc->descs_per_op = 0;
318 
319 	hw_desc->cbc = XOR_CBCR_TGT_BIT;
320 	if (flags & DMA_PREP_INTERRUPT)
321 		/* Enable interrupt on completion */
322 		hw_desc->cbc |= XOR_CBCR_CBCE_BIT;
323 }
324 
325 #define DMA_CTRL_FLAGS_LAST	DMA_PREP_FENCE
326 #define DMA_PREP_ZERO_P		(DMA_CTRL_FLAGS_LAST << 1)
327 #define DMA_PREP_ZERO_Q		(DMA_PREP_ZERO_P << 1)
328 
329 /**
330  * ppc440spe_desc_init_dma01pq - initialize the descriptors for PQ operation
331  * with DMA0/1
332  */
333 static void ppc440spe_desc_init_dma01pq(struct ppc440spe_adma_desc_slot *desc,
334 				int dst_cnt, int src_cnt, unsigned long flags,
335 				unsigned long op)
336 {
337 	struct dma_cdb *hw_desc;
338 	struct ppc440spe_adma_desc_slot *iter;
339 	u8 dopc;
340 
341 	/* Common initialization of a PQ descriptors chain */
342 	set_bits(op, &desc->flags);
343 	desc->src_cnt = src_cnt;
344 	desc->dst_cnt = dst_cnt;
345 
346 	/* WXOR MULTICAST if both P and Q are being computed
347 	 * MV_SG1_SG2 if Q only
348 	 */
349 	dopc = (desc->dst_cnt == DMA_DEST_MAX_NUM) ?
350 		DMA_CDB_OPC_MULTICAST : DMA_CDB_OPC_MV_SG1_SG2;
351 
352 	list_for_each_entry(iter, &desc->group_list, chain_node) {
353 		hw_desc = iter->hw_desc;
354 		memset(iter->hw_desc, 0, sizeof(struct dma_cdb));
355 
356 		if (likely(!list_is_last(&iter->chain_node,
357 				&desc->group_list))) {
358 			/* set 'next' pointer */
359 			iter->hw_next = list_entry(iter->chain_node.next,
360 				struct ppc440spe_adma_desc_slot, chain_node);
361 			clear_bit(PPC440SPE_DESC_INT, &iter->flags);
362 		} else {
363 			/* this is the last descriptor.
364 			 * this slot will be pasted from ADMA level
365 			 * each time it wants to configure parameters
366 			 * of the transaction (src, dst, ...)
367 			 */
368 			iter->hw_next = NULL;
369 			if (flags & DMA_PREP_INTERRUPT)
370 				set_bit(PPC440SPE_DESC_INT, &iter->flags);
371 			else
372 				clear_bit(PPC440SPE_DESC_INT, &iter->flags);
373 		}
374 	}
375 
376 	/* Set OPS depending on WXOR/RXOR type of operation */
377 	if (!test_bit(PPC440SPE_DESC_RXOR, &desc->flags)) {
378 		/* This is a WXOR only chain:
379 		 * - first descriptors are for zeroing destinations
380 		 *   if PPC440SPE_ZERO_P/Q set;
381 		 * - descriptors remained are for GF-XOR operations.
382 		 */
383 		iter = list_first_entry(&desc->group_list,
384 					struct ppc440spe_adma_desc_slot,
385 					chain_node);
386 
387 		if (test_bit(PPC440SPE_ZERO_P, &desc->flags)) {
388 			hw_desc = iter->hw_desc;
389 			hw_desc->opc = DMA_CDB_OPC_MV_SG1_SG2;
390 			iter = list_first_entry(&iter->chain_node,
391 					struct ppc440spe_adma_desc_slot,
392 					chain_node);
393 		}
394 
395 		if (test_bit(PPC440SPE_ZERO_Q, &desc->flags)) {
396 			hw_desc = iter->hw_desc;
397 			hw_desc->opc = DMA_CDB_OPC_MV_SG1_SG2;
398 			iter = list_first_entry(&iter->chain_node,
399 					struct ppc440spe_adma_desc_slot,
400 					chain_node);
401 		}
402 
403 		list_for_each_entry_from(iter, &desc->group_list, chain_node) {
404 			hw_desc = iter->hw_desc;
405 			hw_desc->opc = dopc;
406 		}
407 	} else {
408 		/* This is either RXOR-only or mixed RXOR/WXOR */
409 
410 		/* The first 1 or 2 slots in chain are always RXOR,
411 		 * if need to calculate P & Q, then there are two
412 		 * RXOR slots; if only P or only Q, then there is one
413 		 */
414 		iter = list_first_entry(&desc->group_list,
415 					struct ppc440spe_adma_desc_slot,
416 					chain_node);
417 		hw_desc = iter->hw_desc;
418 		hw_desc->opc = DMA_CDB_OPC_MV_SG1_SG2;
419 
420 		if (desc->dst_cnt == DMA_DEST_MAX_NUM) {
421 			iter = list_first_entry(&iter->chain_node,
422 						struct ppc440spe_adma_desc_slot,
423 						chain_node);
424 			hw_desc = iter->hw_desc;
425 			hw_desc->opc = DMA_CDB_OPC_MV_SG1_SG2;
426 		}
427 
428 		/* The remaining descs (if any) are WXORs */
429 		if (test_bit(PPC440SPE_DESC_WXOR, &desc->flags)) {
430 			iter = list_first_entry(&iter->chain_node,
431 						struct ppc440spe_adma_desc_slot,
432 						chain_node);
433 			list_for_each_entry_from(iter, &desc->group_list,
434 						chain_node) {
435 				hw_desc = iter->hw_desc;
436 				hw_desc->opc = dopc;
437 			}
438 		}
439 	}
440 }
441 
442 /**
443  * ppc440spe_desc_init_dma01pqzero_sum - initialize the descriptor
444  * for PQ_ZERO_SUM operation
445  */
446 static void ppc440spe_desc_init_dma01pqzero_sum(
447 				struct ppc440spe_adma_desc_slot *desc,
448 				int dst_cnt, int src_cnt)
449 {
450 	struct dma_cdb *hw_desc;
451 	struct ppc440spe_adma_desc_slot *iter;
452 	int i = 0;
453 	u8 dopc = (dst_cnt == 2) ? DMA_CDB_OPC_MULTICAST :
454 				   DMA_CDB_OPC_MV_SG1_SG2;
455 	/*
456 	 * Initialize starting from 2nd or 3rd descriptor dependent
457 	 * on dst_cnt. First one or two slots are for cloning P
458 	 * and/or Q to chan->pdest and/or chan->qdest as we have
459 	 * to preserve original P/Q.
460 	 */
461 	iter = list_first_entry(&desc->group_list,
462 				struct ppc440spe_adma_desc_slot, chain_node);
463 	iter = list_entry(iter->chain_node.next,
464 			  struct ppc440spe_adma_desc_slot, chain_node);
465 
466 	if (dst_cnt > 1) {
467 		iter = list_entry(iter->chain_node.next,
468 				  struct ppc440spe_adma_desc_slot, chain_node);
469 	}
470 	/* initialize each source descriptor in chain */
471 	list_for_each_entry_from(iter, &desc->group_list, chain_node) {
472 		hw_desc = iter->hw_desc;
473 		memset(iter->hw_desc, 0, sizeof(struct dma_cdb));
474 		iter->src_cnt = 0;
475 		iter->dst_cnt = 0;
476 
477 		/* This is a ZERO_SUM operation:
478 		 * - <src_cnt> descriptors starting from 2nd or 3rd
479 		 *   descriptor are for GF-XOR operations;
480 		 * - remaining <dst_cnt> descriptors are for checking the result
481 		 */
482 		if (i++ < src_cnt)
483 			/* MV_SG1_SG2 if only Q is being verified
484 			 * MULTICAST if both P and Q are being verified
485 			 */
486 			hw_desc->opc = dopc;
487 		else
488 			/* DMA_CDB_OPC_DCHECK128 operation */
489 			hw_desc->opc = DMA_CDB_OPC_DCHECK128;
490 
491 		if (likely(!list_is_last(&iter->chain_node,
492 					 &desc->group_list))) {
493 			/* set 'next' pointer */
494 			iter->hw_next = list_entry(iter->chain_node.next,
495 						struct ppc440spe_adma_desc_slot,
496 						chain_node);
497 		} else {
498 			/* this is the last descriptor.
499 			 * this slot will be pasted from ADMA level
500 			 * each time it wants to configure parameters
501 			 * of the transaction (src, dst, ...)
502 			 */
503 			iter->hw_next = NULL;
504 			/* always enable interrupt generation since we get
505 			 * the status of pqzero from the handler
506 			 */
507 			set_bit(PPC440SPE_DESC_INT, &iter->flags);
508 		}
509 	}
510 	desc->src_cnt = src_cnt;
511 	desc->dst_cnt = dst_cnt;
512 }
513 
514 /**
515  * ppc440spe_desc_init_memcpy - initialize the descriptor for MEMCPY operation
516  */
517 static void ppc440spe_desc_init_memcpy(struct ppc440spe_adma_desc_slot *desc,
518 					unsigned long flags)
519 {
520 	struct dma_cdb *hw_desc = desc->hw_desc;
521 
522 	memset(desc->hw_desc, 0, sizeof(struct dma_cdb));
523 	desc->hw_next = NULL;
524 	desc->src_cnt = 1;
525 	desc->dst_cnt = 1;
526 
527 	if (flags & DMA_PREP_INTERRUPT)
528 		set_bit(PPC440SPE_DESC_INT, &desc->flags);
529 	else
530 		clear_bit(PPC440SPE_DESC_INT, &desc->flags);
531 
532 	hw_desc->opc = DMA_CDB_OPC_MV_SG1_SG2;
533 }
534 
535 /**
536  * ppc440spe_desc_init_memset - initialize the descriptor for MEMSET operation
537  */
538 static void ppc440spe_desc_init_memset(struct ppc440spe_adma_desc_slot *desc,
539 					int value, unsigned long flags)
540 {
541 	struct dma_cdb *hw_desc = desc->hw_desc;
542 
543 	memset(desc->hw_desc, 0, sizeof(struct dma_cdb));
544 	desc->hw_next = NULL;
545 	desc->src_cnt = 1;
546 	desc->dst_cnt = 1;
547 
548 	if (flags & DMA_PREP_INTERRUPT)
549 		set_bit(PPC440SPE_DESC_INT, &desc->flags);
550 	else
551 		clear_bit(PPC440SPE_DESC_INT, &desc->flags);
552 
553 	hw_desc->sg1u = hw_desc->sg1l = cpu_to_le32((u32)value);
554 	hw_desc->sg3u = hw_desc->sg3l = cpu_to_le32((u32)value);
555 	hw_desc->opc = DMA_CDB_OPC_DFILL128;
556 }
557 
558 /**
559  * ppc440spe_desc_set_src_addr - set source address into the descriptor
560  */
561 static void ppc440spe_desc_set_src_addr(struct ppc440spe_adma_desc_slot *desc,
562 					struct ppc440spe_adma_chan *chan,
563 					int src_idx, dma_addr_t addrh,
564 					dma_addr_t addrl)
565 {
566 	struct dma_cdb *dma_hw_desc;
567 	struct xor_cb *xor_hw_desc;
568 	phys_addr_t addr64, tmplow, tmphi;
569 
570 	switch (chan->device->id) {
571 	case PPC440SPE_DMA0_ID:
572 	case PPC440SPE_DMA1_ID:
573 		if (!addrh) {
574 			addr64 = addrl;
575 			tmphi = (addr64 >> 32);
576 			tmplow = (addr64 & 0xFFFFFFFF);
577 		} else {
578 			tmphi = addrh;
579 			tmplow = addrl;
580 		}
581 		dma_hw_desc = desc->hw_desc;
582 		dma_hw_desc->sg1l = cpu_to_le32((u32)tmplow);
583 		dma_hw_desc->sg1u |= cpu_to_le32((u32)tmphi);
584 		break;
585 	case PPC440SPE_XOR_ID:
586 		xor_hw_desc = desc->hw_desc;
587 		xor_hw_desc->ops[src_idx].l = addrl;
588 		xor_hw_desc->ops[src_idx].h |= addrh;
589 		break;
590 	}
591 }
592 
593 /**
594  * ppc440spe_desc_set_src_mult - set source address mult into the descriptor
595  */
596 static void ppc440spe_desc_set_src_mult(struct ppc440spe_adma_desc_slot *desc,
597 			struct ppc440spe_adma_chan *chan, u32 mult_index,
598 			int sg_index, unsigned char mult_value)
599 {
600 	struct dma_cdb *dma_hw_desc;
601 	struct xor_cb *xor_hw_desc;
602 	u32 *psgu;
603 
604 	switch (chan->device->id) {
605 	case PPC440SPE_DMA0_ID:
606 	case PPC440SPE_DMA1_ID:
607 		dma_hw_desc = desc->hw_desc;
608 
609 		switch (sg_index) {
610 		/* for RXOR operations set multiplier
611 		 * into source cued address
612 		 */
613 		case DMA_CDB_SG_SRC:
614 			psgu = &dma_hw_desc->sg1u;
615 			break;
616 		/* for WXOR operations set multiplier
617 		 * into destination cued address(es)
618 		 */
619 		case DMA_CDB_SG_DST1:
620 			psgu = &dma_hw_desc->sg2u;
621 			break;
622 		case DMA_CDB_SG_DST2:
623 			psgu = &dma_hw_desc->sg3u;
624 			break;
625 		default:
626 			BUG();
627 		}
628 
629 		*psgu |= cpu_to_le32(mult_value << mult_index);
630 		break;
631 	case PPC440SPE_XOR_ID:
632 		xor_hw_desc = desc->hw_desc;
633 		break;
634 	default:
635 		BUG();
636 	}
637 }
638 
639 /**
640  * ppc440spe_desc_set_dest_addr - set destination address into the descriptor
641  */
642 static void ppc440spe_desc_set_dest_addr(struct ppc440spe_adma_desc_slot *desc,
643 				struct ppc440spe_adma_chan *chan,
644 				dma_addr_t addrh, dma_addr_t addrl,
645 				u32 dst_idx)
646 {
647 	struct dma_cdb *dma_hw_desc;
648 	struct xor_cb *xor_hw_desc;
649 	phys_addr_t addr64, tmphi, tmplow;
650 	u32 *psgu, *psgl;
651 
652 	switch (chan->device->id) {
653 	case PPC440SPE_DMA0_ID:
654 	case PPC440SPE_DMA1_ID:
655 		if (!addrh) {
656 			addr64 = addrl;
657 			tmphi = (addr64 >> 32);
658 			tmplow = (addr64 & 0xFFFFFFFF);
659 		} else {
660 			tmphi = addrh;
661 			tmplow = addrl;
662 		}
663 		dma_hw_desc = desc->hw_desc;
664 
665 		psgu = dst_idx ? &dma_hw_desc->sg3u : &dma_hw_desc->sg2u;
666 		psgl = dst_idx ? &dma_hw_desc->sg3l : &dma_hw_desc->sg2l;
667 
668 		*psgl = cpu_to_le32((u32)tmplow);
669 		*psgu |= cpu_to_le32((u32)tmphi);
670 		break;
671 	case PPC440SPE_XOR_ID:
672 		xor_hw_desc = desc->hw_desc;
673 		xor_hw_desc->cbtal = addrl;
674 		xor_hw_desc->cbtah |= addrh;
675 		break;
676 	}
677 }
678 
679 /**
680  * ppc440spe_desc_set_byte_count - set number of data bytes involved
681  * into the operation
682  */
683 static void ppc440spe_desc_set_byte_count(struct ppc440spe_adma_desc_slot *desc,
684 				struct ppc440spe_adma_chan *chan,
685 				u32 byte_count)
686 {
687 	struct dma_cdb *dma_hw_desc;
688 	struct xor_cb *xor_hw_desc;
689 
690 	switch (chan->device->id) {
691 	case PPC440SPE_DMA0_ID:
692 	case PPC440SPE_DMA1_ID:
693 		dma_hw_desc = desc->hw_desc;
694 		dma_hw_desc->cnt = cpu_to_le32(byte_count);
695 		break;
696 	case PPC440SPE_XOR_ID:
697 		xor_hw_desc = desc->hw_desc;
698 		xor_hw_desc->cbbc = byte_count;
699 		break;
700 	}
701 }
702 
703 /**
704  * ppc440spe_desc_set_rxor_block_size - set RXOR block size
705  */
706 static inline void ppc440spe_desc_set_rxor_block_size(u32 byte_count)
707 {
708 	/* assume that byte_count is aligned on the 512-boundary;
709 	 * thus write it directly to the register (bits 23:31 are
710 	 * reserved there).
711 	 */
712 	dcr_write(ppc440spe_mq_dcr_host, DCRN_MQ0_CF2H, byte_count);
713 }
714 
715 /**
716  * ppc440spe_desc_set_dcheck - set CHECK pattern
717  */
718 static void ppc440spe_desc_set_dcheck(struct ppc440spe_adma_desc_slot *desc,
719 				struct ppc440spe_adma_chan *chan, u8 *qword)
720 {
721 	struct dma_cdb *dma_hw_desc;
722 
723 	switch (chan->device->id) {
724 	case PPC440SPE_DMA0_ID:
725 	case PPC440SPE_DMA1_ID:
726 		dma_hw_desc = desc->hw_desc;
727 		iowrite32(qword[0], &dma_hw_desc->sg3l);
728 		iowrite32(qword[4], &dma_hw_desc->sg3u);
729 		iowrite32(qword[8], &dma_hw_desc->sg2l);
730 		iowrite32(qword[12], &dma_hw_desc->sg2u);
731 		break;
732 	default:
733 		BUG();
734 	}
735 }
736 
737 /**
738  * ppc440spe_xor_set_link - set link address in xor CB
739  */
740 static void ppc440spe_xor_set_link(struct ppc440spe_adma_desc_slot *prev_desc,
741 				struct ppc440spe_adma_desc_slot *next_desc)
742 {
743 	struct xor_cb *xor_hw_desc = prev_desc->hw_desc;
744 
745 	if (unlikely(!next_desc || !(next_desc->phys))) {
746 		printk(KERN_ERR "%s: next_desc=0x%p; next_desc->phys=0x%llx\n",
747 			__func__, next_desc,
748 			next_desc ? next_desc->phys : 0);
749 		BUG();
750 	}
751 
752 	xor_hw_desc->cbs = 0;
753 	xor_hw_desc->cblal = next_desc->phys;
754 	xor_hw_desc->cblah = 0;
755 	xor_hw_desc->cbc |= XOR_CBCR_LNK_BIT;
756 }
757 
758 /**
759  * ppc440spe_desc_set_link - set the address of descriptor following this
760  * descriptor in chain
761  */
762 static void ppc440spe_desc_set_link(struct ppc440spe_adma_chan *chan,
763 				struct ppc440spe_adma_desc_slot *prev_desc,
764 				struct ppc440spe_adma_desc_slot *next_desc)
765 {
766 	unsigned long flags;
767 	struct ppc440spe_adma_desc_slot *tail = next_desc;
768 
769 	if (unlikely(!prev_desc || !next_desc ||
770 		(prev_desc->hw_next && prev_desc->hw_next != next_desc))) {
771 		/* If previous next is overwritten something is wrong.
772 		 * though we may refetch from append to initiate list
773 		 * processing; in this case - it's ok.
774 		 */
775 		printk(KERN_ERR "%s: prev_desc=0x%p; next_desc=0x%p; "
776 			"prev->hw_next=0x%p\n", __func__, prev_desc,
777 			next_desc, prev_desc ? prev_desc->hw_next : 0);
778 		BUG();
779 	}
780 
781 	local_irq_save(flags);
782 
783 	/* do s/w chaining both for DMA and XOR descriptors */
784 	prev_desc->hw_next = next_desc;
785 
786 	switch (chan->device->id) {
787 	case PPC440SPE_DMA0_ID:
788 	case PPC440SPE_DMA1_ID:
789 		break;
790 	case PPC440SPE_XOR_ID:
791 		/* bind descriptor to the chain */
792 		while (tail->hw_next)
793 			tail = tail->hw_next;
794 		xor_last_linked = tail;
795 
796 		if (prev_desc == xor_last_submit)
797 			/* do not link to the last submitted CB */
798 			break;
799 		ppc440spe_xor_set_link(prev_desc, next_desc);
800 		break;
801 	}
802 
803 	local_irq_restore(flags);
804 }
805 
806 /**
807  * ppc440spe_desc_get_link - get the address of the descriptor that
808  * follows this one
809  */
810 static inline u32 ppc440spe_desc_get_link(struct ppc440spe_adma_desc_slot *desc,
811 					struct ppc440spe_adma_chan *chan)
812 {
813 	if (!desc->hw_next)
814 		return 0;
815 
816 	return desc->hw_next->phys;
817 }
818 
819 /**
820  * ppc440spe_desc_is_aligned - check alignment
821  */
822 static inline int ppc440spe_desc_is_aligned(
823 	struct ppc440spe_adma_desc_slot *desc, int num_slots)
824 {
825 	return (desc->idx & (num_slots - 1)) ? 0 : 1;
826 }
827 
828 /**
829  * ppc440spe_chan_xor_slot_count - get the number of slots necessary for
830  * XOR operation
831  */
832 static int ppc440spe_chan_xor_slot_count(size_t len, int src_cnt,
833 			int *slots_per_op)
834 {
835 	int slot_cnt;
836 
837 	/* each XOR descriptor provides up to 16 source operands */
838 	slot_cnt = *slots_per_op = (src_cnt + XOR_MAX_OPS - 1)/XOR_MAX_OPS;
839 
840 	if (likely(len <= PPC440SPE_ADMA_XOR_MAX_BYTE_COUNT))
841 		return slot_cnt;
842 
843 	printk(KERN_ERR "%s: len %d > max %d !!\n",
844 		__func__, len, PPC440SPE_ADMA_XOR_MAX_BYTE_COUNT);
845 	BUG();
846 	return slot_cnt;
847 }
848 
849 /**
850  * ppc440spe_dma2_pq_slot_count - get the number of slots necessary for
851  * DMA2 PQ operation
852  */
853 static int ppc440spe_dma2_pq_slot_count(dma_addr_t *srcs,
854 		int src_cnt, size_t len)
855 {
856 	signed long long order = 0;
857 	int state = 0;
858 	int addr_count = 0;
859 	int i;
860 	for (i = 1; i < src_cnt; i++) {
861 		dma_addr_t cur_addr = srcs[i];
862 		dma_addr_t old_addr = srcs[i-1];
863 		switch (state) {
864 		case 0:
865 			if (cur_addr == old_addr + len) {
866 				/* direct RXOR */
867 				order = 1;
868 				state = 1;
869 				if (i == src_cnt-1)
870 					addr_count++;
871 			} else if (old_addr == cur_addr + len) {
872 				/* reverse RXOR */
873 				order = -1;
874 				state = 1;
875 				if (i == src_cnt-1)
876 					addr_count++;
877 			} else {
878 				state = 3;
879 			}
880 			break;
881 		case 1:
882 			if (i == src_cnt-2 || (order == -1
883 				&& cur_addr != old_addr - len)) {
884 				order = 0;
885 				state = 0;
886 				addr_count++;
887 			} else if (cur_addr == old_addr + len*order) {
888 				state = 2;
889 				if (i == src_cnt-1)
890 					addr_count++;
891 			} else if (cur_addr == old_addr + 2*len) {
892 				state = 2;
893 				if (i == src_cnt-1)
894 					addr_count++;
895 			} else if (cur_addr == old_addr + 3*len) {
896 				state = 2;
897 				if (i == src_cnt-1)
898 					addr_count++;
899 			} else {
900 				order = 0;
901 				state = 0;
902 				addr_count++;
903 			}
904 			break;
905 		case 2:
906 			order = 0;
907 			state = 0;
908 			addr_count++;
909 				break;
910 		}
911 		if (state == 3)
912 			break;
913 	}
914 	if (src_cnt <= 1 || (state != 1 && state != 2)) {
915 		pr_err("%s: src_cnt=%d, state=%d, addr_count=%d, order=%lld\n",
916 			__func__, src_cnt, state, addr_count, order);
917 		for (i = 0; i < src_cnt; i++)
918 			pr_err("\t[%d] 0x%llx \n", i, srcs[i]);
919 		BUG();
920 	}
921 
922 	return (addr_count + XOR_MAX_OPS - 1) / XOR_MAX_OPS;
923 }
924 
925 
926 /******************************************************************************
927  * ADMA channel low-level routines
928  ******************************************************************************/
929 
930 static u32
931 ppc440spe_chan_get_current_descriptor(struct ppc440spe_adma_chan *chan);
932 static void ppc440spe_chan_append(struct ppc440spe_adma_chan *chan);
933 
934 /**
935  * ppc440spe_adma_device_clear_eot_status - interrupt ack to XOR or DMA engine
936  */
937 static void ppc440spe_adma_device_clear_eot_status(
938 					struct ppc440spe_adma_chan *chan)
939 {
940 	struct dma_regs *dma_reg;
941 	struct xor_regs *xor_reg;
942 	u8 *p = chan->device->dma_desc_pool_virt;
943 	struct dma_cdb *cdb;
944 	u32 rv, i;
945 
946 	switch (chan->device->id) {
947 	case PPC440SPE_DMA0_ID:
948 	case PPC440SPE_DMA1_ID:
949 		/* read FIFO to ack */
950 		dma_reg = chan->device->dma_reg;
951 		while ((rv = ioread32(&dma_reg->csfpl))) {
952 			i = rv & DMA_CDB_ADDR_MSK;
953 			cdb = (struct dma_cdb *)&p[i -
954 			    (u32)chan->device->dma_desc_pool];
955 
956 			/* Clear opcode to ack. This is necessary for
957 			 * ZeroSum operations only
958 			 */
959 			cdb->opc = 0;
960 
961 			if (test_bit(PPC440SPE_RXOR_RUN,
962 			    &ppc440spe_rxor_state)) {
963 				/* probably this is a completed RXOR op,
964 				 * get pointer to CDB using the fact that
965 				 * physical and virtual addresses of CDB
966 				 * in pools have the same offsets
967 				 */
968 				if (le32_to_cpu(cdb->sg1u) &
969 				    DMA_CUED_XOR_BASE) {
970 					/* this is a RXOR */
971 					clear_bit(PPC440SPE_RXOR_RUN,
972 						  &ppc440spe_rxor_state);
973 				}
974 			}
975 
976 			if (rv & DMA_CDB_STATUS_MSK) {
977 				/* ZeroSum check failed
978 				 */
979 				struct ppc440spe_adma_desc_slot *iter;
980 				dma_addr_t phys = rv & ~DMA_CDB_MSK;
981 
982 				/*
983 				 * Update the status of corresponding
984 				 * descriptor.
985 				 */
986 				list_for_each_entry(iter, &chan->chain,
987 				    chain_node) {
988 					if (iter->phys == phys)
989 						break;
990 				}
991 				/*
992 				 * if cannot find the corresponding
993 				 * slot it's a bug
994 				 */
995 				BUG_ON(&iter->chain_node == &chan->chain);
996 
997 				if (iter->xor_check_result) {
998 					if (test_bit(PPC440SPE_DESC_PCHECK,
999 						     &iter->flags)) {
1000 						*iter->xor_check_result |=
1001 							SUM_CHECK_P_RESULT;
1002 					} else
1003 					if (test_bit(PPC440SPE_DESC_QCHECK,
1004 						     &iter->flags)) {
1005 						*iter->xor_check_result |=
1006 							SUM_CHECK_Q_RESULT;
1007 					} else
1008 						BUG();
1009 				}
1010 			}
1011 		}
1012 
1013 		rv = ioread32(&dma_reg->dsts);
1014 		if (rv) {
1015 			pr_err("DMA%d err status: 0x%x\n",
1016 			       chan->device->id, rv);
1017 			/* write back to clear */
1018 			iowrite32(rv, &dma_reg->dsts);
1019 		}
1020 		break;
1021 	case PPC440SPE_XOR_ID:
1022 		/* reset status bits to ack */
1023 		xor_reg = chan->device->xor_reg;
1024 		rv = ioread32be(&xor_reg->sr);
1025 		iowrite32be(rv, &xor_reg->sr);
1026 
1027 		if (rv & (XOR_IE_ICBIE_BIT|XOR_IE_ICIE_BIT|XOR_IE_RPTIE_BIT)) {
1028 			if (rv & XOR_IE_RPTIE_BIT) {
1029 				/* Read PLB Timeout Error.
1030 				 * Try to resubmit the CB
1031 				 */
1032 				u32 val = ioread32be(&xor_reg->ccbalr);
1033 
1034 				iowrite32be(val, &xor_reg->cblalr);
1035 
1036 				val = ioread32be(&xor_reg->crsr);
1037 				iowrite32be(val | XOR_CRSR_XAE_BIT,
1038 					    &xor_reg->crsr);
1039 			} else
1040 				pr_err("XOR ERR 0x%x status\n", rv);
1041 			break;
1042 		}
1043 
1044 		/*  if the XORcore is idle, but there are unprocessed CBs
1045 		 * then refetch the s/w chain here
1046 		 */
1047 		if (!(ioread32be(&xor_reg->sr) & XOR_SR_XCP_BIT) &&
1048 		    do_xor_refetch)
1049 			ppc440spe_chan_append(chan);
1050 		break;
1051 	}
1052 }
1053 
1054 /**
1055  * ppc440spe_chan_is_busy - get the channel status
1056  */
1057 static int ppc440spe_chan_is_busy(struct ppc440spe_adma_chan *chan)
1058 {
1059 	struct dma_regs *dma_reg;
1060 	struct xor_regs *xor_reg;
1061 	int busy = 0;
1062 
1063 	switch (chan->device->id) {
1064 	case PPC440SPE_DMA0_ID:
1065 	case PPC440SPE_DMA1_ID:
1066 		dma_reg = chan->device->dma_reg;
1067 		/*  if command FIFO's head and tail pointers are equal and
1068 		 * status tail is the same as command, then channel is free
1069 		 */
1070 		if (ioread16(&dma_reg->cpfhp) != ioread16(&dma_reg->cpftp) ||
1071 		    ioread16(&dma_reg->cpftp) != ioread16(&dma_reg->csftp))
1072 			busy = 1;
1073 		break;
1074 	case PPC440SPE_XOR_ID:
1075 		/* use the special status bit for the XORcore
1076 		 */
1077 		xor_reg = chan->device->xor_reg;
1078 		busy = (ioread32be(&xor_reg->sr) & XOR_SR_XCP_BIT) ? 1 : 0;
1079 		break;
1080 	}
1081 
1082 	return busy;
1083 }
1084 
1085 /**
1086  * ppc440spe_chan_set_first_xor_descriptor -  init XORcore chain
1087  */
1088 static void ppc440spe_chan_set_first_xor_descriptor(
1089 				struct ppc440spe_adma_chan *chan,
1090 				struct ppc440spe_adma_desc_slot *next_desc)
1091 {
1092 	struct xor_regs *xor_reg = chan->device->xor_reg;
1093 
1094 	if (ioread32be(&xor_reg->sr) & XOR_SR_XCP_BIT)
1095 		printk(KERN_INFO "%s: Warn: XORcore is running "
1096 			"when try to set the first CDB!\n",
1097 			__func__);
1098 
1099 	xor_last_submit = xor_last_linked = next_desc;
1100 
1101 	iowrite32be(XOR_CRSR_64BA_BIT, &xor_reg->crsr);
1102 
1103 	iowrite32be(next_desc->phys, &xor_reg->cblalr);
1104 	iowrite32be(0, &xor_reg->cblahr);
1105 	iowrite32be(ioread32be(&xor_reg->cbcr) | XOR_CBCR_LNK_BIT,
1106 		    &xor_reg->cbcr);
1107 
1108 	chan->hw_chain_inited = 1;
1109 }
1110 
1111 /**
1112  * ppc440spe_dma_put_desc - put DMA0,1 descriptor to FIFO.
1113  * called with irqs disabled
1114  */
1115 static void ppc440spe_dma_put_desc(struct ppc440spe_adma_chan *chan,
1116 		struct ppc440spe_adma_desc_slot *desc)
1117 {
1118 	u32 pcdb;
1119 	struct dma_regs *dma_reg = chan->device->dma_reg;
1120 
1121 	pcdb = desc->phys;
1122 	if (!test_bit(PPC440SPE_DESC_INT, &desc->flags))
1123 		pcdb |= DMA_CDB_NO_INT;
1124 
1125 	chan_last_sub[chan->device->id] = desc;
1126 
1127 	ADMA_LL_DBG(print_cb(chan, desc->hw_desc));
1128 
1129 	iowrite32(pcdb, &dma_reg->cpfpl);
1130 }
1131 
1132 /**
1133  * ppc440spe_chan_append - update the h/w chain in the channel
1134  */
1135 static void ppc440spe_chan_append(struct ppc440spe_adma_chan *chan)
1136 {
1137 	struct xor_regs *xor_reg;
1138 	struct ppc440spe_adma_desc_slot *iter;
1139 	struct xor_cb *xcb;
1140 	u32 cur_desc;
1141 	unsigned long flags;
1142 
1143 	local_irq_save(flags);
1144 
1145 	switch (chan->device->id) {
1146 	case PPC440SPE_DMA0_ID:
1147 	case PPC440SPE_DMA1_ID:
1148 		cur_desc = ppc440spe_chan_get_current_descriptor(chan);
1149 
1150 		if (likely(cur_desc)) {
1151 			iter = chan_last_sub[chan->device->id];
1152 			BUG_ON(!iter);
1153 		} else {
1154 			/* first peer */
1155 			iter = chan_first_cdb[chan->device->id];
1156 			BUG_ON(!iter);
1157 			ppc440spe_dma_put_desc(chan, iter);
1158 			chan->hw_chain_inited = 1;
1159 		}
1160 
1161 		/* is there something new to append */
1162 		if (!iter->hw_next)
1163 			break;
1164 
1165 		/* flush descriptors from the s/w queue to fifo */
1166 		list_for_each_entry_continue(iter, &chan->chain, chain_node) {
1167 			ppc440spe_dma_put_desc(chan, iter);
1168 			if (!iter->hw_next)
1169 				break;
1170 		}
1171 		break;
1172 	case PPC440SPE_XOR_ID:
1173 		/* update h/w links and refetch */
1174 		if (!xor_last_submit->hw_next)
1175 			break;
1176 
1177 		xor_reg = chan->device->xor_reg;
1178 		/* the last linked CDB has to generate an interrupt
1179 		 * that we'd be able to append the next lists to h/w
1180 		 * regardless of the XOR engine state at the moment of
1181 		 * appending of these next lists
1182 		 */
1183 		xcb = xor_last_linked->hw_desc;
1184 		xcb->cbc |= XOR_CBCR_CBCE_BIT;
1185 
1186 		if (!(ioread32be(&xor_reg->sr) & XOR_SR_XCP_BIT)) {
1187 			/* XORcore is idle. Refetch now */
1188 			do_xor_refetch = 0;
1189 			ppc440spe_xor_set_link(xor_last_submit,
1190 				xor_last_submit->hw_next);
1191 
1192 			ADMA_LL_DBG(print_cb_list(chan,
1193 				xor_last_submit->hw_next));
1194 
1195 			xor_last_submit = xor_last_linked;
1196 			iowrite32be(ioread32be(&xor_reg->crsr) |
1197 				    XOR_CRSR_RCBE_BIT | XOR_CRSR_64BA_BIT,
1198 				    &xor_reg->crsr);
1199 		} else {
1200 			/* XORcore is running. Refetch later in the handler */
1201 			do_xor_refetch = 1;
1202 		}
1203 
1204 		break;
1205 	}
1206 
1207 	local_irq_restore(flags);
1208 }
1209 
1210 /**
1211  * ppc440spe_chan_get_current_descriptor - get the currently executed descriptor
1212  */
1213 static u32
1214 ppc440spe_chan_get_current_descriptor(struct ppc440spe_adma_chan *chan)
1215 {
1216 	struct dma_regs *dma_reg;
1217 	struct xor_regs *xor_reg;
1218 
1219 	if (unlikely(!chan->hw_chain_inited))
1220 		/* h/w descriptor chain is not initialized yet */
1221 		return 0;
1222 
1223 	switch (chan->device->id) {
1224 	case PPC440SPE_DMA0_ID:
1225 	case PPC440SPE_DMA1_ID:
1226 		dma_reg = chan->device->dma_reg;
1227 		return ioread32(&dma_reg->acpl) & (~DMA_CDB_MSK);
1228 	case PPC440SPE_XOR_ID:
1229 		xor_reg = chan->device->xor_reg;
1230 		return ioread32be(&xor_reg->ccbalr);
1231 	}
1232 	return 0;
1233 }
1234 
1235 /**
1236  * ppc440spe_chan_run - enable the channel
1237  */
1238 static void ppc440spe_chan_run(struct ppc440spe_adma_chan *chan)
1239 {
1240 	struct xor_regs *xor_reg;
1241 
1242 	switch (chan->device->id) {
1243 	case PPC440SPE_DMA0_ID:
1244 	case PPC440SPE_DMA1_ID:
1245 		/* DMAs are always enabled, do nothing */
1246 		break;
1247 	case PPC440SPE_XOR_ID:
1248 		/* drain write buffer */
1249 		xor_reg = chan->device->xor_reg;
1250 
1251 		/* fetch descriptor pointed to in <link> */
1252 		iowrite32be(XOR_CRSR_64BA_BIT | XOR_CRSR_XAE_BIT,
1253 			    &xor_reg->crsr);
1254 		break;
1255 	}
1256 }
1257 
1258 /******************************************************************************
1259  * ADMA device level
1260  ******************************************************************************/
1261 
1262 static void ppc440spe_chan_start_null_xor(struct ppc440spe_adma_chan *chan);
1263 static int ppc440spe_adma_alloc_chan_resources(struct dma_chan *chan);
1264 
1265 static dma_cookie_t
1266 ppc440spe_adma_tx_submit(struct dma_async_tx_descriptor *tx);
1267 
1268 static void ppc440spe_adma_set_dest(struct ppc440spe_adma_desc_slot *tx,
1269 				    dma_addr_t addr, int index);
1270 static void
1271 ppc440spe_adma_memcpy_xor_set_src(struct ppc440spe_adma_desc_slot *tx,
1272 				  dma_addr_t addr, int index);
1273 
1274 static void
1275 ppc440spe_adma_pq_set_dest(struct ppc440spe_adma_desc_slot *tx,
1276 			   dma_addr_t *paddr, unsigned long flags);
1277 static void
1278 ppc440spe_adma_pq_set_src(struct ppc440spe_adma_desc_slot *tx,
1279 			  dma_addr_t addr, int index);
1280 static void
1281 ppc440spe_adma_pq_set_src_mult(struct ppc440spe_adma_desc_slot *tx,
1282 			       unsigned char mult, int index, int dst_pos);
1283 static void
1284 ppc440spe_adma_pqzero_sum_set_dest(struct ppc440spe_adma_desc_slot *tx,
1285 				   dma_addr_t paddr, dma_addr_t qaddr);
1286 
1287 static struct page *ppc440spe_rxor_srcs[32];
1288 
1289 /**
1290  * ppc440spe_can_rxor - check if the operands may be processed with RXOR
1291  */
1292 static int ppc440spe_can_rxor(struct page **srcs, int src_cnt, size_t len)
1293 {
1294 	int i, order = 0, state = 0;
1295 	int idx = 0;
1296 
1297 	if (unlikely(!(src_cnt > 1)))
1298 		return 0;
1299 
1300 	BUG_ON(src_cnt > ARRAY_SIZE(ppc440spe_rxor_srcs));
1301 
1302 	/* Skip holes in the source list before checking */
1303 	for (i = 0; i < src_cnt; i++) {
1304 		if (!srcs[i])
1305 			continue;
1306 		ppc440spe_rxor_srcs[idx++] = srcs[i];
1307 	}
1308 	src_cnt = idx;
1309 
1310 	for (i = 1; i < src_cnt; i++) {
1311 		char *cur_addr = page_address(ppc440spe_rxor_srcs[i]);
1312 		char *old_addr = page_address(ppc440spe_rxor_srcs[i - 1]);
1313 
1314 		switch (state) {
1315 		case 0:
1316 			if (cur_addr == old_addr + len) {
1317 				/* direct RXOR */
1318 				order = 1;
1319 				state = 1;
1320 			} else if (old_addr == cur_addr + len) {
1321 				/* reverse RXOR */
1322 				order = -1;
1323 				state = 1;
1324 			} else
1325 				goto out;
1326 			break;
1327 		case 1:
1328 			if ((i == src_cnt - 2) ||
1329 			    (order == -1 && cur_addr != old_addr - len)) {
1330 				order = 0;
1331 				state = 0;
1332 			} else if ((cur_addr == old_addr + len * order) ||
1333 				   (cur_addr == old_addr + 2 * len) ||
1334 				   (cur_addr == old_addr + 3 * len)) {
1335 				state = 2;
1336 			} else {
1337 				order = 0;
1338 				state = 0;
1339 			}
1340 			break;
1341 		case 2:
1342 			order = 0;
1343 			state = 0;
1344 			break;
1345 		}
1346 	}
1347 
1348 out:
1349 	if (state == 1 || state == 2)
1350 		return 1;
1351 
1352 	return 0;
1353 }
1354 
1355 /**
1356  * ppc440spe_adma_device_estimate - estimate the efficiency of processing
1357  *	the operation given on this channel. It's assumed that 'chan' is
1358  *	capable to process 'cap' type of operation.
1359  * @chan: channel to use
1360  * @cap: type of transaction
1361  * @dst_lst: array of destination pointers
1362  * @dst_cnt: number of destination operands
1363  * @src_lst: array of source pointers
1364  * @src_cnt: number of source operands
1365  * @src_sz: size of each source operand
1366  */
1367 static int ppc440spe_adma_estimate(struct dma_chan *chan,
1368 	enum dma_transaction_type cap, struct page **dst_lst, int dst_cnt,
1369 	struct page **src_lst, int src_cnt, size_t src_sz)
1370 {
1371 	int ef = 1;
1372 
1373 	if (cap == DMA_PQ || cap == DMA_PQ_VAL) {
1374 		/* If RAID-6 capabilities were not activated don't try
1375 		 * to use them
1376 		 */
1377 		if (unlikely(!ppc440spe_r6_enabled))
1378 			return -1;
1379 	}
1380 	/*  In the current implementation of ppc440spe ADMA driver it
1381 	 * makes sense to pick out only pq case, because it may be
1382 	 * processed:
1383 	 * (1) either using Biskup method on DMA2;
1384 	 * (2) or on DMA0/1.
1385 	 *  Thus we give a favour to (1) if the sources are suitable;
1386 	 * else let it be processed on one of the DMA0/1 engines.
1387 	 *  In the sum_product case where destination is also the
1388 	 * source process it on DMA0/1 only.
1389 	 */
1390 	if (cap == DMA_PQ && chan->chan_id == PPC440SPE_XOR_ID) {
1391 
1392 		if (dst_cnt == 1 && src_cnt == 2 && dst_lst[0] == src_lst[1])
1393 			ef = 0; /* sum_product case, process on DMA0/1 */
1394 		else if (ppc440spe_can_rxor(src_lst, src_cnt, src_sz))
1395 			ef = 3; /* override (DMA0/1 + idle) */
1396 		else
1397 			ef = 0; /* can't process on DMA2 if !rxor */
1398 	}
1399 
1400 	/* channel idleness increases the priority */
1401 	if (likely(ef) &&
1402 	    !ppc440spe_chan_is_busy(to_ppc440spe_adma_chan(chan)))
1403 		ef++;
1404 
1405 	return ef;
1406 }
1407 
1408 struct dma_chan *
1409 ppc440spe_async_tx_find_best_channel(enum dma_transaction_type cap,
1410 	struct page **dst_lst, int dst_cnt, struct page **src_lst,
1411 	int src_cnt, size_t src_sz)
1412 {
1413 	struct dma_chan *best_chan = NULL;
1414 	struct ppc_dma_chan_ref *ref;
1415 	int best_rank = -1;
1416 
1417 	if (unlikely(!src_sz))
1418 		return NULL;
1419 	if (src_sz > PAGE_SIZE) {
1420 		/*
1421 		 * should a user of the api ever pass > PAGE_SIZE requests
1422 		 * we sort out cases where temporary page-sized buffers
1423 		 * are used.
1424 		 */
1425 		switch (cap) {
1426 		case DMA_PQ:
1427 			if (src_cnt == 1 && dst_lst[1] == src_lst[0])
1428 				return NULL;
1429 			if (src_cnt == 2 && dst_lst[1] == src_lst[1])
1430 				return NULL;
1431 			break;
1432 		case DMA_PQ_VAL:
1433 		case DMA_XOR_VAL:
1434 			return NULL;
1435 		default:
1436 			break;
1437 		}
1438 	}
1439 
1440 	list_for_each_entry(ref, &ppc440spe_adma_chan_list, node) {
1441 		if (dma_has_cap(cap, ref->chan->device->cap_mask)) {
1442 			int rank;
1443 
1444 			rank = ppc440spe_adma_estimate(ref->chan, cap, dst_lst,
1445 					dst_cnt, src_lst, src_cnt, src_sz);
1446 			if (rank > best_rank) {
1447 				best_rank = rank;
1448 				best_chan = ref->chan;
1449 			}
1450 		}
1451 	}
1452 
1453 	return best_chan;
1454 }
1455 EXPORT_SYMBOL_GPL(ppc440spe_async_tx_find_best_channel);
1456 
1457 /**
1458  * ppc440spe_get_group_entry - get group entry with index idx
1459  * @tdesc: is the last allocated slot in the group.
1460  */
1461 static struct ppc440spe_adma_desc_slot *
1462 ppc440spe_get_group_entry(struct ppc440spe_adma_desc_slot *tdesc, u32 entry_idx)
1463 {
1464 	struct ppc440spe_adma_desc_slot *iter = tdesc->group_head;
1465 	int i = 0;
1466 
1467 	if (entry_idx < 0 || entry_idx >= (tdesc->src_cnt + tdesc->dst_cnt)) {
1468 		printk("%s: entry_idx %d, src_cnt %d, dst_cnt %d\n",
1469 			__func__, entry_idx, tdesc->src_cnt, tdesc->dst_cnt);
1470 		BUG();
1471 	}
1472 
1473 	list_for_each_entry(iter, &tdesc->group_list, chain_node) {
1474 		if (i++ == entry_idx)
1475 			break;
1476 	}
1477 	return iter;
1478 }
1479 
1480 /**
1481  * ppc440spe_adma_free_slots - flags descriptor slots for reuse
1482  * @slot: Slot to free
1483  * Caller must hold &ppc440spe_chan->lock while calling this function
1484  */
1485 static void ppc440spe_adma_free_slots(struct ppc440spe_adma_desc_slot *slot,
1486 				      struct ppc440spe_adma_chan *chan)
1487 {
1488 	int stride = slot->slots_per_op;
1489 
1490 	while (stride--) {
1491 		slot->slots_per_op = 0;
1492 		slot = list_entry(slot->slot_node.next,
1493 				struct ppc440spe_adma_desc_slot,
1494 				slot_node);
1495 	}
1496 }
1497 
1498 /**
1499  * ppc440spe_adma_run_tx_complete_actions - call functions to be called
1500  * upon completion
1501  */
1502 static dma_cookie_t ppc440spe_adma_run_tx_complete_actions(
1503 		struct ppc440spe_adma_desc_slot *desc,
1504 		struct ppc440spe_adma_chan *chan,
1505 		dma_cookie_t cookie)
1506 {
1507 	int i;
1508 
1509 	BUG_ON(desc->async_tx.cookie < 0);
1510 	if (desc->async_tx.cookie > 0) {
1511 		cookie = desc->async_tx.cookie;
1512 		desc->async_tx.cookie = 0;
1513 
1514 		/* call the callback (must not sleep or submit new
1515 		 * operations to this channel)
1516 		 */
1517 		if (desc->async_tx.callback)
1518 			desc->async_tx.callback(
1519 				desc->async_tx.callback_param);
1520 
1521 		dma_descriptor_unmap(&desc->async_tx);
1522 	}
1523 
1524 	/* run dependent operations */
1525 	dma_run_dependencies(&desc->async_tx);
1526 
1527 	return cookie;
1528 }
1529 
1530 /**
1531  * ppc440spe_adma_clean_slot - clean up CDB slot (if ack is set)
1532  */
1533 static int ppc440spe_adma_clean_slot(struct ppc440spe_adma_desc_slot *desc,
1534 		struct ppc440spe_adma_chan *chan)
1535 {
1536 	/* the client is allowed to attach dependent operations
1537 	 * until 'ack' is set
1538 	 */
1539 	if (!async_tx_test_ack(&desc->async_tx))
1540 		return 0;
1541 
1542 	/* leave the last descriptor in the chain
1543 	 * so we can append to it
1544 	 */
1545 	if (list_is_last(&desc->chain_node, &chan->chain) ||
1546 	    desc->phys == ppc440spe_chan_get_current_descriptor(chan))
1547 		return 1;
1548 
1549 	if (chan->device->id != PPC440SPE_XOR_ID) {
1550 		/* our DMA interrupt handler clears opc field of
1551 		 * each processed descriptor. For all types of
1552 		 * operations except for ZeroSum we do not actually
1553 		 * need ack from the interrupt handler. ZeroSum is a
1554 		 * special case since the result of this operation
1555 		 * is available from the handler only, so if we see
1556 		 * such type of descriptor (which is unprocessed yet)
1557 		 * then leave it in chain.
1558 		 */
1559 		struct dma_cdb *cdb = desc->hw_desc;
1560 		if (cdb->opc == DMA_CDB_OPC_DCHECK128)
1561 			return 1;
1562 	}
1563 
1564 	dev_dbg(chan->device->common.dev, "\tfree slot %llx: %d stride: %d\n",
1565 		desc->phys, desc->idx, desc->slots_per_op);
1566 
1567 	list_del(&desc->chain_node);
1568 	ppc440spe_adma_free_slots(desc, chan);
1569 	return 0;
1570 }
1571 
1572 /**
1573  * __ppc440spe_adma_slot_cleanup - this is the common clean-up routine
1574  *	which runs through the channel CDBs list until reach the descriptor
1575  *	currently processed. When routine determines that all CDBs of group
1576  *	are completed then corresponding callbacks (if any) are called and slots
1577  *	are freed.
1578  */
1579 static void __ppc440spe_adma_slot_cleanup(struct ppc440spe_adma_chan *chan)
1580 {
1581 	struct ppc440spe_adma_desc_slot *iter, *_iter, *group_start = NULL;
1582 	dma_cookie_t cookie = 0;
1583 	u32 current_desc = ppc440spe_chan_get_current_descriptor(chan);
1584 	int busy = ppc440spe_chan_is_busy(chan);
1585 	int seen_current = 0, slot_cnt = 0, slots_per_op = 0;
1586 
1587 	dev_dbg(chan->device->common.dev, "ppc440spe adma%d: %s\n",
1588 		chan->device->id, __func__);
1589 
1590 	if (!current_desc) {
1591 		/*  There were no transactions yet, so
1592 		 * nothing to clean
1593 		 */
1594 		return;
1595 	}
1596 
1597 	/* free completed slots from the chain starting with
1598 	 * the oldest descriptor
1599 	 */
1600 	list_for_each_entry_safe(iter, _iter, &chan->chain,
1601 					chain_node) {
1602 		dev_dbg(chan->device->common.dev, "\tcookie: %d slot: %d "
1603 		    "busy: %d this_desc: %#llx next_desc: %#x "
1604 		    "cur: %#x ack: %d\n",
1605 		    iter->async_tx.cookie, iter->idx, busy, iter->phys,
1606 		    ppc440spe_desc_get_link(iter, chan), current_desc,
1607 		    async_tx_test_ack(&iter->async_tx));
1608 		prefetch(_iter);
1609 		prefetch(&_iter->async_tx);
1610 
1611 		/* do not advance past the current descriptor loaded into the
1612 		 * hardware channel,subsequent descriptors are either in process
1613 		 * or have not been submitted
1614 		 */
1615 		if (seen_current)
1616 			break;
1617 
1618 		/* stop the search if we reach the current descriptor and the
1619 		 * channel is busy, or if it appears that the current descriptor
1620 		 * needs to be re-read (i.e. has been appended to)
1621 		 */
1622 		if (iter->phys == current_desc) {
1623 			BUG_ON(seen_current++);
1624 			if (busy || ppc440spe_desc_get_link(iter, chan)) {
1625 				/* not all descriptors of the group have
1626 				 * been completed; exit.
1627 				 */
1628 				break;
1629 			}
1630 		}
1631 
1632 		/* detect the start of a group transaction */
1633 		if (!slot_cnt && !slots_per_op) {
1634 			slot_cnt = iter->slot_cnt;
1635 			slots_per_op = iter->slots_per_op;
1636 			if (slot_cnt <= slots_per_op) {
1637 				slot_cnt = 0;
1638 				slots_per_op = 0;
1639 			}
1640 		}
1641 
1642 		if (slot_cnt) {
1643 			if (!group_start)
1644 				group_start = iter;
1645 			slot_cnt -= slots_per_op;
1646 		}
1647 
1648 		/* all the members of a group are complete */
1649 		if (slots_per_op != 0 && slot_cnt == 0) {
1650 			struct ppc440spe_adma_desc_slot *grp_iter, *_grp_iter;
1651 			int end_of_chain = 0;
1652 
1653 			/* clean up the group */
1654 			slot_cnt = group_start->slot_cnt;
1655 			grp_iter = group_start;
1656 			list_for_each_entry_safe_from(grp_iter, _grp_iter,
1657 				&chan->chain, chain_node) {
1658 
1659 				cookie = ppc440spe_adma_run_tx_complete_actions(
1660 					grp_iter, chan, cookie);
1661 
1662 				slot_cnt -= slots_per_op;
1663 				end_of_chain = ppc440spe_adma_clean_slot(
1664 				    grp_iter, chan);
1665 				if (end_of_chain && slot_cnt) {
1666 					/* Should wait for ZeroSum completion */
1667 					if (cookie > 0)
1668 						chan->common.completed_cookie = cookie;
1669 					return;
1670 				}
1671 
1672 				if (slot_cnt == 0 || end_of_chain)
1673 					break;
1674 			}
1675 
1676 			/* the group should be complete at this point */
1677 			BUG_ON(slot_cnt);
1678 
1679 			slots_per_op = 0;
1680 			group_start = NULL;
1681 			if (end_of_chain)
1682 				break;
1683 			else
1684 				continue;
1685 		} else if (slots_per_op) /* wait for group completion */
1686 			continue;
1687 
1688 		cookie = ppc440spe_adma_run_tx_complete_actions(iter, chan,
1689 		    cookie);
1690 
1691 		if (ppc440spe_adma_clean_slot(iter, chan))
1692 			break;
1693 	}
1694 
1695 	BUG_ON(!seen_current);
1696 
1697 	if (cookie > 0) {
1698 		chan->common.completed_cookie = cookie;
1699 		pr_debug("\tcompleted cookie %d\n", cookie);
1700 	}
1701 
1702 }
1703 
1704 /**
1705  * ppc440spe_adma_tasklet - clean up watch-dog initiator
1706  */
1707 static void ppc440spe_adma_tasklet(unsigned long data)
1708 {
1709 	struct ppc440spe_adma_chan *chan = (struct ppc440spe_adma_chan *) data;
1710 
1711 	spin_lock_nested(&chan->lock, SINGLE_DEPTH_NESTING);
1712 	__ppc440spe_adma_slot_cleanup(chan);
1713 	spin_unlock(&chan->lock);
1714 }
1715 
1716 /**
1717  * ppc440spe_adma_slot_cleanup - clean up scheduled initiator
1718  */
1719 static void ppc440spe_adma_slot_cleanup(struct ppc440spe_adma_chan *chan)
1720 {
1721 	spin_lock_bh(&chan->lock);
1722 	__ppc440spe_adma_slot_cleanup(chan);
1723 	spin_unlock_bh(&chan->lock);
1724 }
1725 
1726 /**
1727  * ppc440spe_adma_alloc_slots - allocate free slots (if any)
1728  */
1729 static struct ppc440spe_adma_desc_slot *ppc440spe_adma_alloc_slots(
1730 		struct ppc440spe_adma_chan *chan, int num_slots,
1731 		int slots_per_op)
1732 {
1733 	struct ppc440spe_adma_desc_slot *iter = NULL, *_iter;
1734 	struct ppc440spe_adma_desc_slot *alloc_start = NULL;
1735 	struct list_head chain = LIST_HEAD_INIT(chain);
1736 	int slots_found, retry = 0;
1737 
1738 
1739 	BUG_ON(!num_slots || !slots_per_op);
1740 	/* start search from the last allocated descrtiptor
1741 	 * if a contiguous allocation can not be found start searching
1742 	 * from the beginning of the list
1743 	 */
1744 retry:
1745 	slots_found = 0;
1746 	if (retry == 0)
1747 		iter = chan->last_used;
1748 	else
1749 		iter = list_entry(&chan->all_slots,
1750 				  struct ppc440spe_adma_desc_slot,
1751 				  slot_node);
1752 	list_for_each_entry_safe_continue(iter, _iter, &chan->all_slots,
1753 	    slot_node) {
1754 		prefetch(_iter);
1755 		prefetch(&_iter->async_tx);
1756 		if (iter->slots_per_op) {
1757 			slots_found = 0;
1758 			continue;
1759 		}
1760 
1761 		/* start the allocation if the slot is correctly aligned */
1762 		if (!slots_found++)
1763 			alloc_start = iter;
1764 
1765 		if (slots_found == num_slots) {
1766 			struct ppc440spe_adma_desc_slot *alloc_tail = NULL;
1767 			struct ppc440spe_adma_desc_slot *last_used = NULL;
1768 
1769 			iter = alloc_start;
1770 			while (num_slots) {
1771 				int i;
1772 				/* pre-ack all but the last descriptor */
1773 				if (num_slots != slots_per_op)
1774 					async_tx_ack(&iter->async_tx);
1775 
1776 				list_add_tail(&iter->chain_node, &chain);
1777 				alloc_tail = iter;
1778 				iter->async_tx.cookie = 0;
1779 				iter->hw_next = NULL;
1780 				iter->flags = 0;
1781 				iter->slot_cnt = num_slots;
1782 				iter->xor_check_result = NULL;
1783 				for (i = 0; i < slots_per_op; i++) {
1784 					iter->slots_per_op = slots_per_op - i;
1785 					last_used = iter;
1786 					iter = list_entry(iter->slot_node.next,
1787 						struct ppc440spe_adma_desc_slot,
1788 						slot_node);
1789 				}
1790 				num_slots -= slots_per_op;
1791 			}
1792 			alloc_tail->group_head = alloc_start;
1793 			alloc_tail->async_tx.cookie = -EBUSY;
1794 			list_splice(&chain, &alloc_tail->group_list);
1795 			chan->last_used = last_used;
1796 			return alloc_tail;
1797 		}
1798 	}
1799 	if (!retry++)
1800 		goto retry;
1801 
1802 	/* try to free some slots if the allocation fails */
1803 	tasklet_schedule(&chan->irq_tasklet);
1804 	return NULL;
1805 }
1806 
1807 /**
1808  * ppc440spe_adma_alloc_chan_resources -  allocate pools for CDB slots
1809  */
1810 static int ppc440spe_adma_alloc_chan_resources(struct dma_chan *chan)
1811 {
1812 	struct ppc440spe_adma_chan *ppc440spe_chan;
1813 	struct ppc440spe_adma_desc_slot *slot = NULL;
1814 	char *hw_desc;
1815 	int i, db_sz;
1816 	int init;
1817 
1818 	ppc440spe_chan = to_ppc440spe_adma_chan(chan);
1819 	init = ppc440spe_chan->slots_allocated ? 0 : 1;
1820 	chan->chan_id = ppc440spe_chan->device->id;
1821 
1822 	/* Allocate descriptor slots */
1823 	i = ppc440spe_chan->slots_allocated;
1824 	if (ppc440spe_chan->device->id != PPC440SPE_XOR_ID)
1825 		db_sz = sizeof(struct dma_cdb);
1826 	else
1827 		db_sz = sizeof(struct xor_cb);
1828 
1829 	for (; i < (ppc440spe_chan->device->pool_size / db_sz); i++) {
1830 		slot = kzalloc(sizeof(struct ppc440spe_adma_desc_slot),
1831 			       GFP_KERNEL);
1832 		if (!slot) {
1833 			printk(KERN_INFO "SPE ADMA Channel only initialized"
1834 				" %d descriptor slots", i--);
1835 			break;
1836 		}
1837 
1838 		hw_desc = (char *) ppc440spe_chan->device->dma_desc_pool_virt;
1839 		slot->hw_desc = (void *) &hw_desc[i * db_sz];
1840 		dma_async_tx_descriptor_init(&slot->async_tx, chan);
1841 		slot->async_tx.tx_submit = ppc440spe_adma_tx_submit;
1842 		INIT_LIST_HEAD(&slot->chain_node);
1843 		INIT_LIST_HEAD(&slot->slot_node);
1844 		INIT_LIST_HEAD(&slot->group_list);
1845 		slot->phys = ppc440spe_chan->device->dma_desc_pool + i * db_sz;
1846 		slot->idx = i;
1847 
1848 		spin_lock_bh(&ppc440spe_chan->lock);
1849 		ppc440spe_chan->slots_allocated++;
1850 		list_add_tail(&slot->slot_node, &ppc440spe_chan->all_slots);
1851 		spin_unlock_bh(&ppc440spe_chan->lock);
1852 	}
1853 
1854 	if (i && !ppc440spe_chan->last_used) {
1855 		ppc440spe_chan->last_used =
1856 			list_entry(ppc440spe_chan->all_slots.next,
1857 				struct ppc440spe_adma_desc_slot,
1858 				slot_node);
1859 	}
1860 
1861 	dev_dbg(ppc440spe_chan->device->common.dev,
1862 		"ppc440spe adma%d: allocated %d descriptor slots\n",
1863 		ppc440spe_chan->device->id, i);
1864 
1865 	/* initialize the channel and the chain with a null operation */
1866 	if (init) {
1867 		switch (ppc440spe_chan->device->id) {
1868 		case PPC440SPE_DMA0_ID:
1869 		case PPC440SPE_DMA1_ID:
1870 			ppc440spe_chan->hw_chain_inited = 0;
1871 			/* Use WXOR for self-testing */
1872 			if (!ppc440spe_r6_tchan)
1873 				ppc440spe_r6_tchan = ppc440spe_chan;
1874 			break;
1875 		case PPC440SPE_XOR_ID:
1876 			ppc440spe_chan_start_null_xor(ppc440spe_chan);
1877 			break;
1878 		default:
1879 			BUG();
1880 		}
1881 		ppc440spe_chan->needs_unmap = 1;
1882 	}
1883 
1884 	return (i > 0) ? i : -ENOMEM;
1885 }
1886 
1887 /**
1888  * ppc440spe_rxor_set_region_data -
1889  */
1890 static void ppc440spe_rxor_set_region(struct ppc440spe_adma_desc_slot *desc,
1891 	u8 xor_arg_no, u32 mask)
1892 {
1893 	struct xor_cb *xcb = desc->hw_desc;
1894 
1895 	xcb->ops[xor_arg_no].h |= mask;
1896 }
1897 
1898 /**
1899  * ppc440spe_rxor_set_src -
1900  */
1901 static void ppc440spe_rxor_set_src(struct ppc440spe_adma_desc_slot *desc,
1902 	u8 xor_arg_no, dma_addr_t addr)
1903 {
1904 	struct xor_cb *xcb = desc->hw_desc;
1905 
1906 	xcb->ops[xor_arg_no].h |= DMA_CUED_XOR_BASE;
1907 	xcb->ops[xor_arg_no].l = addr;
1908 }
1909 
1910 /**
1911  * ppc440spe_rxor_set_mult -
1912  */
1913 static void ppc440spe_rxor_set_mult(struct ppc440spe_adma_desc_slot *desc,
1914 	u8 xor_arg_no, u8 idx, u8 mult)
1915 {
1916 	struct xor_cb *xcb = desc->hw_desc;
1917 
1918 	xcb->ops[xor_arg_no].h |= mult << (DMA_CUED_MULT1_OFF + idx * 8);
1919 }
1920 
1921 /**
1922  * ppc440spe_adma_check_threshold - append CDBs to h/w chain if threshold
1923  *	has been achieved
1924  */
1925 static void ppc440spe_adma_check_threshold(struct ppc440spe_adma_chan *chan)
1926 {
1927 	dev_dbg(chan->device->common.dev, "ppc440spe adma%d: pending: %d\n",
1928 		chan->device->id, chan->pending);
1929 
1930 	if (chan->pending >= PPC440SPE_ADMA_THRESHOLD) {
1931 		chan->pending = 0;
1932 		ppc440spe_chan_append(chan);
1933 	}
1934 }
1935 
1936 /**
1937  * ppc440spe_adma_tx_submit - submit new descriptor group to the channel
1938  *	(it's not necessary that descriptors will be submitted to the h/w
1939  *	chains too right now)
1940  */
1941 static dma_cookie_t ppc440spe_adma_tx_submit(struct dma_async_tx_descriptor *tx)
1942 {
1943 	struct ppc440spe_adma_desc_slot *sw_desc;
1944 	struct ppc440spe_adma_chan *chan = to_ppc440spe_adma_chan(tx->chan);
1945 	struct ppc440spe_adma_desc_slot *group_start, *old_chain_tail;
1946 	int slot_cnt;
1947 	int slots_per_op;
1948 	dma_cookie_t cookie;
1949 
1950 	sw_desc = tx_to_ppc440spe_adma_slot(tx);
1951 
1952 	group_start = sw_desc->group_head;
1953 	slot_cnt = group_start->slot_cnt;
1954 	slots_per_op = group_start->slots_per_op;
1955 
1956 	spin_lock_bh(&chan->lock);
1957 	cookie = dma_cookie_assign(tx);
1958 
1959 	if (unlikely(list_empty(&chan->chain))) {
1960 		/* first peer */
1961 		list_splice_init(&sw_desc->group_list, &chan->chain);
1962 		chan_first_cdb[chan->device->id] = group_start;
1963 	} else {
1964 		/* isn't first peer, bind CDBs to chain */
1965 		old_chain_tail = list_entry(chan->chain.prev,
1966 					struct ppc440spe_adma_desc_slot,
1967 					chain_node);
1968 		list_splice_init(&sw_desc->group_list,
1969 		    &old_chain_tail->chain_node);
1970 		/* fix up the hardware chain */
1971 		ppc440spe_desc_set_link(chan, old_chain_tail, group_start);
1972 	}
1973 
1974 	/* increment the pending count by the number of operations */
1975 	chan->pending += slot_cnt / slots_per_op;
1976 	ppc440spe_adma_check_threshold(chan);
1977 	spin_unlock_bh(&chan->lock);
1978 
1979 	dev_dbg(chan->device->common.dev,
1980 		"ppc440spe adma%d: %s cookie: %d slot: %d tx %p\n",
1981 		chan->device->id, __func__,
1982 		sw_desc->async_tx.cookie, sw_desc->idx, sw_desc);
1983 
1984 	return cookie;
1985 }
1986 
1987 /**
1988  * ppc440spe_adma_prep_dma_interrupt - prepare CDB for a pseudo DMA operation
1989  */
1990 static struct dma_async_tx_descriptor *ppc440spe_adma_prep_dma_interrupt(
1991 		struct dma_chan *chan, unsigned long flags)
1992 {
1993 	struct ppc440spe_adma_chan *ppc440spe_chan;
1994 	struct ppc440spe_adma_desc_slot *sw_desc, *group_start;
1995 	int slot_cnt, slots_per_op;
1996 
1997 	ppc440spe_chan = to_ppc440spe_adma_chan(chan);
1998 
1999 	dev_dbg(ppc440spe_chan->device->common.dev,
2000 		"ppc440spe adma%d: %s\n", ppc440spe_chan->device->id,
2001 		__func__);
2002 
2003 	spin_lock_bh(&ppc440spe_chan->lock);
2004 	slot_cnt = slots_per_op = 1;
2005 	sw_desc = ppc440spe_adma_alloc_slots(ppc440spe_chan, slot_cnt,
2006 			slots_per_op);
2007 	if (sw_desc) {
2008 		group_start = sw_desc->group_head;
2009 		ppc440spe_desc_init_interrupt(group_start, ppc440spe_chan);
2010 		group_start->unmap_len = 0;
2011 		sw_desc->async_tx.flags = flags;
2012 	}
2013 	spin_unlock_bh(&ppc440spe_chan->lock);
2014 
2015 	return sw_desc ? &sw_desc->async_tx : NULL;
2016 }
2017 
2018 /**
2019  * ppc440spe_adma_prep_dma_memcpy - prepare CDB for a MEMCPY operation
2020  */
2021 static struct dma_async_tx_descriptor *ppc440spe_adma_prep_dma_memcpy(
2022 		struct dma_chan *chan, dma_addr_t dma_dest,
2023 		dma_addr_t dma_src, size_t len, unsigned long flags)
2024 {
2025 	struct ppc440spe_adma_chan *ppc440spe_chan;
2026 	struct ppc440spe_adma_desc_slot *sw_desc, *group_start;
2027 	int slot_cnt, slots_per_op;
2028 
2029 	ppc440spe_chan = to_ppc440spe_adma_chan(chan);
2030 
2031 	if (unlikely(!len))
2032 		return NULL;
2033 
2034 	BUG_ON(len > PPC440SPE_ADMA_DMA_MAX_BYTE_COUNT);
2035 
2036 	spin_lock_bh(&ppc440spe_chan->lock);
2037 
2038 	dev_dbg(ppc440spe_chan->device->common.dev,
2039 		"ppc440spe adma%d: %s len: %u int_en %d\n",
2040 		ppc440spe_chan->device->id, __func__, len,
2041 		flags & DMA_PREP_INTERRUPT ? 1 : 0);
2042 	slot_cnt = slots_per_op = 1;
2043 	sw_desc = ppc440spe_adma_alloc_slots(ppc440spe_chan, slot_cnt,
2044 		slots_per_op);
2045 	if (sw_desc) {
2046 		group_start = sw_desc->group_head;
2047 		ppc440spe_desc_init_memcpy(group_start, flags);
2048 		ppc440spe_adma_set_dest(group_start, dma_dest, 0);
2049 		ppc440spe_adma_memcpy_xor_set_src(group_start, dma_src, 0);
2050 		ppc440spe_desc_set_byte_count(group_start, ppc440spe_chan, len);
2051 		sw_desc->unmap_len = len;
2052 		sw_desc->async_tx.flags = flags;
2053 	}
2054 	spin_unlock_bh(&ppc440spe_chan->lock);
2055 
2056 	return sw_desc ? &sw_desc->async_tx : NULL;
2057 }
2058 
2059 /**
2060  * ppc440spe_adma_prep_dma_xor - prepare CDB for a XOR operation
2061  */
2062 static struct dma_async_tx_descriptor *ppc440spe_adma_prep_dma_xor(
2063 		struct dma_chan *chan, dma_addr_t dma_dest,
2064 		dma_addr_t *dma_src, u32 src_cnt, size_t len,
2065 		unsigned long flags)
2066 {
2067 	struct ppc440spe_adma_chan *ppc440spe_chan;
2068 	struct ppc440spe_adma_desc_slot *sw_desc, *group_start;
2069 	int slot_cnt, slots_per_op;
2070 
2071 	ppc440spe_chan = to_ppc440spe_adma_chan(chan);
2072 
2073 	ADMA_LL_DBG(prep_dma_xor_dbg(ppc440spe_chan->device->id,
2074 				     dma_dest, dma_src, src_cnt));
2075 	if (unlikely(!len))
2076 		return NULL;
2077 	BUG_ON(len > PPC440SPE_ADMA_XOR_MAX_BYTE_COUNT);
2078 
2079 	dev_dbg(ppc440spe_chan->device->common.dev,
2080 		"ppc440spe adma%d: %s src_cnt: %d len: %u int_en: %d\n",
2081 		ppc440spe_chan->device->id, __func__, src_cnt, len,
2082 		flags & DMA_PREP_INTERRUPT ? 1 : 0);
2083 
2084 	spin_lock_bh(&ppc440spe_chan->lock);
2085 	slot_cnt = ppc440spe_chan_xor_slot_count(len, src_cnt, &slots_per_op);
2086 	sw_desc = ppc440spe_adma_alloc_slots(ppc440spe_chan, slot_cnt,
2087 			slots_per_op);
2088 	if (sw_desc) {
2089 		group_start = sw_desc->group_head;
2090 		ppc440spe_desc_init_xor(group_start, src_cnt, flags);
2091 		ppc440spe_adma_set_dest(group_start, dma_dest, 0);
2092 		while (src_cnt--)
2093 			ppc440spe_adma_memcpy_xor_set_src(group_start,
2094 				dma_src[src_cnt], src_cnt);
2095 		ppc440spe_desc_set_byte_count(group_start, ppc440spe_chan, len);
2096 		sw_desc->unmap_len = len;
2097 		sw_desc->async_tx.flags = flags;
2098 	}
2099 	spin_unlock_bh(&ppc440spe_chan->lock);
2100 
2101 	return sw_desc ? &sw_desc->async_tx : NULL;
2102 }
2103 
2104 static inline void
2105 ppc440spe_desc_set_xor_src_cnt(struct ppc440spe_adma_desc_slot *desc,
2106 				int src_cnt);
2107 static void ppc440spe_init_rxor_cursor(struct ppc440spe_rxor *cursor);
2108 
2109 /**
2110  * ppc440spe_adma_init_dma2rxor_slot -
2111  */
2112 static void ppc440spe_adma_init_dma2rxor_slot(
2113 		struct ppc440spe_adma_desc_slot *desc,
2114 		dma_addr_t *src, int src_cnt)
2115 {
2116 	int i;
2117 
2118 	/* initialize CDB */
2119 	for (i = 0; i < src_cnt; i++) {
2120 		ppc440spe_adma_dma2rxor_prep_src(desc, &desc->rxor_cursor, i,
2121 						 desc->src_cnt, (u32)src[i]);
2122 	}
2123 }
2124 
2125 /**
2126  * ppc440spe_dma01_prep_mult -
2127  * for Q operation where destination is also the source
2128  */
2129 static struct ppc440spe_adma_desc_slot *ppc440spe_dma01_prep_mult(
2130 		struct ppc440spe_adma_chan *ppc440spe_chan,
2131 		dma_addr_t *dst, int dst_cnt, dma_addr_t *src, int src_cnt,
2132 		const unsigned char *scf, size_t len, unsigned long flags)
2133 {
2134 	struct ppc440spe_adma_desc_slot *sw_desc = NULL;
2135 	unsigned long op = 0;
2136 	int slot_cnt;
2137 
2138 	set_bit(PPC440SPE_DESC_WXOR, &op);
2139 	slot_cnt = 2;
2140 
2141 	spin_lock_bh(&ppc440spe_chan->lock);
2142 
2143 	/* use WXOR, each descriptor occupies one slot */
2144 	sw_desc = ppc440spe_adma_alloc_slots(ppc440spe_chan, slot_cnt, 1);
2145 	if (sw_desc) {
2146 		struct ppc440spe_adma_chan *chan;
2147 		struct ppc440spe_adma_desc_slot *iter;
2148 		struct dma_cdb *hw_desc;
2149 
2150 		chan = to_ppc440spe_adma_chan(sw_desc->async_tx.chan);
2151 		set_bits(op, &sw_desc->flags);
2152 		sw_desc->src_cnt = src_cnt;
2153 		sw_desc->dst_cnt = dst_cnt;
2154 		/* First descriptor, zero data in the destination and copy it
2155 		 * to q page using MULTICAST transfer.
2156 		 */
2157 		iter = list_first_entry(&sw_desc->group_list,
2158 					struct ppc440spe_adma_desc_slot,
2159 					chain_node);
2160 		memset(iter->hw_desc, 0, sizeof(struct dma_cdb));
2161 		/* set 'next' pointer */
2162 		iter->hw_next = list_entry(iter->chain_node.next,
2163 					   struct ppc440spe_adma_desc_slot,
2164 					   chain_node);
2165 		clear_bit(PPC440SPE_DESC_INT, &iter->flags);
2166 		hw_desc = iter->hw_desc;
2167 		hw_desc->opc = DMA_CDB_OPC_MULTICAST;
2168 
2169 		ppc440spe_desc_set_dest_addr(iter, chan,
2170 					     DMA_CUED_XOR_BASE, dst[0], 0);
2171 		ppc440spe_desc_set_dest_addr(iter, chan, 0, dst[1], 1);
2172 		ppc440spe_desc_set_src_addr(iter, chan, 0, DMA_CUED_XOR_HB,
2173 					    src[0]);
2174 		ppc440spe_desc_set_byte_count(iter, ppc440spe_chan, len);
2175 		iter->unmap_len = len;
2176 
2177 		/*
2178 		 * Second descriptor, multiply data from the q page
2179 		 * and store the result in real destination.
2180 		 */
2181 		iter = list_first_entry(&iter->chain_node,
2182 					struct ppc440spe_adma_desc_slot,
2183 					chain_node);
2184 		memset(iter->hw_desc, 0, sizeof(struct dma_cdb));
2185 		iter->hw_next = NULL;
2186 		if (flags & DMA_PREP_INTERRUPT)
2187 			set_bit(PPC440SPE_DESC_INT, &iter->flags);
2188 		else
2189 			clear_bit(PPC440SPE_DESC_INT, &iter->flags);
2190 
2191 		hw_desc = iter->hw_desc;
2192 		hw_desc->opc = DMA_CDB_OPC_MV_SG1_SG2;
2193 		ppc440spe_desc_set_src_addr(iter, chan, 0,
2194 					    DMA_CUED_XOR_HB, dst[1]);
2195 		ppc440spe_desc_set_dest_addr(iter, chan,
2196 					     DMA_CUED_XOR_BASE, dst[0], 0);
2197 
2198 		ppc440spe_desc_set_src_mult(iter, chan, DMA_CUED_MULT1_OFF,
2199 					    DMA_CDB_SG_DST1, scf[0]);
2200 		ppc440spe_desc_set_byte_count(iter, ppc440spe_chan, len);
2201 		iter->unmap_len = len;
2202 		sw_desc->async_tx.flags = flags;
2203 	}
2204 
2205 	spin_unlock_bh(&ppc440spe_chan->lock);
2206 
2207 	return sw_desc;
2208 }
2209 
2210 /**
2211  * ppc440spe_dma01_prep_sum_product -
2212  * Dx = A*(P+Pxy) + B*(Q+Qxy) operation where destination is also
2213  * the source.
2214  */
2215 static struct ppc440spe_adma_desc_slot *ppc440spe_dma01_prep_sum_product(
2216 		struct ppc440spe_adma_chan *ppc440spe_chan,
2217 		dma_addr_t *dst, dma_addr_t *src, int src_cnt,
2218 		const unsigned char *scf, size_t len, unsigned long flags)
2219 {
2220 	struct ppc440spe_adma_desc_slot *sw_desc = NULL;
2221 	unsigned long op = 0;
2222 	int slot_cnt;
2223 
2224 	set_bit(PPC440SPE_DESC_WXOR, &op);
2225 	slot_cnt = 3;
2226 
2227 	spin_lock_bh(&ppc440spe_chan->lock);
2228 
2229 	/* WXOR, each descriptor occupies one slot */
2230 	sw_desc = ppc440spe_adma_alloc_slots(ppc440spe_chan, slot_cnt, 1);
2231 	if (sw_desc) {
2232 		struct ppc440spe_adma_chan *chan;
2233 		struct ppc440spe_adma_desc_slot *iter;
2234 		struct dma_cdb *hw_desc;
2235 
2236 		chan = to_ppc440spe_adma_chan(sw_desc->async_tx.chan);
2237 		set_bits(op, &sw_desc->flags);
2238 		sw_desc->src_cnt = src_cnt;
2239 		sw_desc->dst_cnt = 1;
2240 		/* 1st descriptor, src[1] data to q page and zero destination */
2241 		iter = list_first_entry(&sw_desc->group_list,
2242 					struct ppc440spe_adma_desc_slot,
2243 					chain_node);
2244 		memset(iter->hw_desc, 0, sizeof(struct dma_cdb));
2245 		iter->hw_next = list_entry(iter->chain_node.next,
2246 					   struct ppc440spe_adma_desc_slot,
2247 					   chain_node);
2248 		clear_bit(PPC440SPE_DESC_INT, &iter->flags);
2249 		hw_desc = iter->hw_desc;
2250 		hw_desc->opc = DMA_CDB_OPC_MULTICAST;
2251 
2252 		ppc440spe_desc_set_dest_addr(iter, chan, DMA_CUED_XOR_BASE,
2253 					     *dst, 0);
2254 		ppc440spe_desc_set_dest_addr(iter, chan, 0,
2255 					     ppc440spe_chan->qdest, 1);
2256 		ppc440spe_desc_set_src_addr(iter, chan, 0, DMA_CUED_XOR_HB,
2257 					    src[1]);
2258 		ppc440spe_desc_set_byte_count(iter, ppc440spe_chan, len);
2259 		iter->unmap_len = len;
2260 
2261 		/* 2nd descriptor, multiply src[1] data and store the
2262 		 * result in destination */
2263 		iter = list_first_entry(&iter->chain_node,
2264 					struct ppc440spe_adma_desc_slot,
2265 					chain_node);
2266 		memset(iter->hw_desc, 0, sizeof(struct dma_cdb));
2267 		/* set 'next' pointer */
2268 		iter->hw_next = list_entry(iter->chain_node.next,
2269 					   struct ppc440spe_adma_desc_slot,
2270 					   chain_node);
2271 		if (flags & DMA_PREP_INTERRUPT)
2272 			set_bit(PPC440SPE_DESC_INT, &iter->flags);
2273 		else
2274 			clear_bit(PPC440SPE_DESC_INT, &iter->flags);
2275 
2276 		hw_desc = iter->hw_desc;
2277 		hw_desc->opc = DMA_CDB_OPC_MV_SG1_SG2;
2278 		ppc440spe_desc_set_src_addr(iter, chan, 0, DMA_CUED_XOR_HB,
2279 					    ppc440spe_chan->qdest);
2280 		ppc440spe_desc_set_dest_addr(iter, chan, DMA_CUED_XOR_BASE,
2281 					     *dst, 0);
2282 		ppc440spe_desc_set_src_mult(iter, chan,	DMA_CUED_MULT1_OFF,
2283 					    DMA_CDB_SG_DST1, scf[1]);
2284 		ppc440spe_desc_set_byte_count(iter, ppc440spe_chan, len);
2285 		iter->unmap_len = len;
2286 
2287 		/*
2288 		 * 3rd descriptor, multiply src[0] data and xor it
2289 		 * with destination
2290 		 */
2291 		iter = list_first_entry(&iter->chain_node,
2292 					struct ppc440spe_adma_desc_slot,
2293 					chain_node);
2294 		memset(iter->hw_desc, 0, sizeof(struct dma_cdb));
2295 		iter->hw_next = NULL;
2296 		if (flags & DMA_PREP_INTERRUPT)
2297 			set_bit(PPC440SPE_DESC_INT, &iter->flags);
2298 		else
2299 			clear_bit(PPC440SPE_DESC_INT, &iter->flags);
2300 
2301 		hw_desc = iter->hw_desc;
2302 		hw_desc->opc = DMA_CDB_OPC_MV_SG1_SG2;
2303 		ppc440spe_desc_set_src_addr(iter, chan, 0, DMA_CUED_XOR_HB,
2304 					    src[0]);
2305 		ppc440spe_desc_set_dest_addr(iter, chan, DMA_CUED_XOR_BASE,
2306 					     *dst, 0);
2307 		ppc440spe_desc_set_src_mult(iter, chan, DMA_CUED_MULT1_OFF,
2308 					    DMA_CDB_SG_DST1, scf[0]);
2309 		ppc440spe_desc_set_byte_count(iter, ppc440spe_chan, len);
2310 		iter->unmap_len = len;
2311 		sw_desc->async_tx.flags = flags;
2312 	}
2313 
2314 	spin_unlock_bh(&ppc440spe_chan->lock);
2315 
2316 	return sw_desc;
2317 }
2318 
2319 static struct ppc440spe_adma_desc_slot *ppc440spe_dma01_prep_pq(
2320 		struct ppc440spe_adma_chan *ppc440spe_chan,
2321 		dma_addr_t *dst, int dst_cnt, dma_addr_t *src, int src_cnt,
2322 		const unsigned char *scf, size_t len, unsigned long flags)
2323 {
2324 	int slot_cnt;
2325 	struct ppc440spe_adma_desc_slot *sw_desc = NULL, *iter;
2326 	unsigned long op = 0;
2327 	unsigned char mult = 1;
2328 
2329 	pr_debug("%s: dst_cnt %d, src_cnt %d, len %d\n",
2330 		 __func__, dst_cnt, src_cnt, len);
2331 	/*  select operations WXOR/RXOR depending on the
2332 	 * source addresses of operators and the number
2333 	 * of destinations (RXOR support only Q-parity calculations)
2334 	 */
2335 	set_bit(PPC440SPE_DESC_WXOR, &op);
2336 	if (!test_and_set_bit(PPC440SPE_RXOR_RUN, &ppc440spe_rxor_state)) {
2337 		/* no active RXOR;
2338 		 * do RXOR if:
2339 		 * - there are more than 1 source,
2340 		 * - len is aligned on 512-byte boundary,
2341 		 * - source addresses fit to one of 4 possible regions.
2342 		 */
2343 		if (src_cnt > 1 &&
2344 		    !(len & MQ0_CF2H_RXOR_BS_MASK) &&
2345 		    (src[0] + len) == src[1]) {
2346 			/* may do RXOR R1 R2 */
2347 			set_bit(PPC440SPE_DESC_RXOR, &op);
2348 			if (src_cnt != 2) {
2349 				/* may try to enhance region of RXOR */
2350 				if ((src[1] + len) == src[2]) {
2351 					/* do RXOR R1 R2 R3 */
2352 					set_bit(PPC440SPE_DESC_RXOR123,
2353 						&op);
2354 				} else if ((src[1] + len * 2) == src[2]) {
2355 					/* do RXOR R1 R2 R4 */
2356 					set_bit(PPC440SPE_DESC_RXOR124, &op);
2357 				} else if ((src[1] + len * 3) == src[2]) {
2358 					/* do RXOR R1 R2 R5 */
2359 					set_bit(PPC440SPE_DESC_RXOR125,
2360 						&op);
2361 				} else {
2362 					/* do RXOR R1 R2 */
2363 					set_bit(PPC440SPE_DESC_RXOR12,
2364 						&op);
2365 				}
2366 			} else {
2367 				/* do RXOR R1 R2 */
2368 				set_bit(PPC440SPE_DESC_RXOR12, &op);
2369 			}
2370 		}
2371 
2372 		if (!test_bit(PPC440SPE_DESC_RXOR, &op)) {
2373 			/* can not do this operation with RXOR */
2374 			clear_bit(PPC440SPE_RXOR_RUN,
2375 				&ppc440spe_rxor_state);
2376 		} else {
2377 			/* can do; set block size right now */
2378 			ppc440spe_desc_set_rxor_block_size(len);
2379 		}
2380 	}
2381 
2382 	/* Number of necessary slots depends on operation type selected */
2383 	if (!test_bit(PPC440SPE_DESC_RXOR, &op)) {
2384 		/*  This is a WXOR only chain. Need descriptors for each
2385 		 * source to GF-XOR them with WXOR, and need descriptors
2386 		 * for each destination to zero them with WXOR
2387 		 */
2388 		slot_cnt = src_cnt;
2389 
2390 		if (flags & DMA_PREP_ZERO_P) {
2391 			slot_cnt++;
2392 			set_bit(PPC440SPE_ZERO_P, &op);
2393 		}
2394 		if (flags & DMA_PREP_ZERO_Q) {
2395 			slot_cnt++;
2396 			set_bit(PPC440SPE_ZERO_Q, &op);
2397 		}
2398 	} else {
2399 		/*  Need 1/2 descriptor for RXOR operation, and
2400 		 * need (src_cnt - (2 or 3)) for WXOR of sources
2401 		 * remained (if any)
2402 		 */
2403 		slot_cnt = dst_cnt;
2404 
2405 		if (flags & DMA_PREP_ZERO_P)
2406 			set_bit(PPC440SPE_ZERO_P, &op);
2407 		if (flags & DMA_PREP_ZERO_Q)
2408 			set_bit(PPC440SPE_ZERO_Q, &op);
2409 
2410 		if (test_bit(PPC440SPE_DESC_RXOR12, &op))
2411 			slot_cnt += src_cnt - 2;
2412 		else
2413 			slot_cnt += src_cnt - 3;
2414 
2415 		/*  Thus we have either RXOR only chain or
2416 		 * mixed RXOR/WXOR
2417 		 */
2418 		if (slot_cnt == dst_cnt)
2419 			/* RXOR only chain */
2420 			clear_bit(PPC440SPE_DESC_WXOR, &op);
2421 	}
2422 
2423 	spin_lock_bh(&ppc440spe_chan->lock);
2424 	/* for both RXOR/WXOR each descriptor occupies one slot */
2425 	sw_desc = ppc440spe_adma_alloc_slots(ppc440spe_chan, slot_cnt, 1);
2426 	if (sw_desc) {
2427 		ppc440spe_desc_init_dma01pq(sw_desc, dst_cnt, src_cnt,
2428 				flags, op);
2429 
2430 		/* setup dst/src/mult */
2431 		pr_debug("%s: set dst descriptor 0, 1: 0x%016llx, 0x%016llx\n",
2432 			 __func__, dst[0], dst[1]);
2433 		ppc440spe_adma_pq_set_dest(sw_desc, dst, flags);
2434 		while (src_cnt--) {
2435 			ppc440spe_adma_pq_set_src(sw_desc, src[src_cnt],
2436 						  src_cnt);
2437 
2438 			/* NOTE: "Multi = 0 is equivalent to = 1" as it
2439 			 * stated in 440SPSPe_RAID6_Addendum_UM_1_17.pdf
2440 			 * doesn't work for RXOR with DMA0/1! Instead, multi=0
2441 			 * leads to zeroing source data after RXOR.
2442 			 * So, for P case set-up mult=1 explicitly.
2443 			 */
2444 			if (!(flags & DMA_PREP_PQ_DISABLE_Q))
2445 				mult = scf[src_cnt];
2446 			ppc440spe_adma_pq_set_src_mult(sw_desc,
2447 				mult, src_cnt,  dst_cnt - 1);
2448 		}
2449 
2450 		/* Setup byte count foreach slot just allocated */
2451 		sw_desc->async_tx.flags = flags;
2452 		list_for_each_entry(iter, &sw_desc->group_list,
2453 				chain_node) {
2454 			ppc440spe_desc_set_byte_count(iter,
2455 				ppc440spe_chan, len);
2456 			iter->unmap_len = len;
2457 		}
2458 	}
2459 	spin_unlock_bh(&ppc440spe_chan->lock);
2460 
2461 	return sw_desc;
2462 }
2463 
2464 static struct ppc440spe_adma_desc_slot *ppc440spe_dma2_prep_pq(
2465 		struct ppc440spe_adma_chan *ppc440spe_chan,
2466 		dma_addr_t *dst, int dst_cnt, dma_addr_t *src, int src_cnt,
2467 		const unsigned char *scf, size_t len, unsigned long flags)
2468 {
2469 	int slot_cnt, descs_per_op;
2470 	struct ppc440spe_adma_desc_slot *sw_desc = NULL, *iter;
2471 	unsigned long op = 0;
2472 	unsigned char mult = 1;
2473 
2474 	BUG_ON(!dst_cnt);
2475 	/*pr_debug("%s: dst_cnt %d, src_cnt %d, len %d\n",
2476 		 __func__, dst_cnt, src_cnt, len);*/
2477 
2478 	spin_lock_bh(&ppc440spe_chan->lock);
2479 	descs_per_op = ppc440spe_dma2_pq_slot_count(src, src_cnt, len);
2480 	if (descs_per_op < 0) {
2481 		spin_unlock_bh(&ppc440spe_chan->lock);
2482 		return NULL;
2483 	}
2484 
2485 	/* depending on number of sources we have 1 or 2 RXOR chains */
2486 	slot_cnt = descs_per_op * dst_cnt;
2487 
2488 	sw_desc = ppc440spe_adma_alloc_slots(ppc440spe_chan, slot_cnt, 1);
2489 	if (sw_desc) {
2490 		op = slot_cnt;
2491 		sw_desc->async_tx.flags = flags;
2492 		list_for_each_entry(iter, &sw_desc->group_list, chain_node) {
2493 			ppc440spe_desc_init_dma2pq(iter, dst_cnt, src_cnt,
2494 				--op ? 0 : flags);
2495 			ppc440spe_desc_set_byte_count(iter, ppc440spe_chan,
2496 				len);
2497 			iter->unmap_len = len;
2498 
2499 			ppc440spe_init_rxor_cursor(&(iter->rxor_cursor));
2500 			iter->rxor_cursor.len = len;
2501 			iter->descs_per_op = descs_per_op;
2502 		}
2503 		op = 0;
2504 		list_for_each_entry(iter, &sw_desc->group_list, chain_node) {
2505 			op++;
2506 			if (op % descs_per_op == 0)
2507 				ppc440spe_adma_init_dma2rxor_slot(iter, src,
2508 								  src_cnt);
2509 			if (likely(!list_is_last(&iter->chain_node,
2510 						 &sw_desc->group_list))) {
2511 				/* set 'next' pointer */
2512 				iter->hw_next =
2513 					list_entry(iter->chain_node.next,
2514 						struct ppc440spe_adma_desc_slot,
2515 						chain_node);
2516 				ppc440spe_xor_set_link(iter, iter->hw_next);
2517 			} else {
2518 				/* this is the last descriptor. */
2519 				iter->hw_next = NULL;
2520 			}
2521 		}
2522 
2523 		/* fixup head descriptor */
2524 		sw_desc->dst_cnt = dst_cnt;
2525 		if (flags & DMA_PREP_ZERO_P)
2526 			set_bit(PPC440SPE_ZERO_P, &sw_desc->flags);
2527 		if (flags & DMA_PREP_ZERO_Q)
2528 			set_bit(PPC440SPE_ZERO_Q, &sw_desc->flags);
2529 
2530 		/* setup dst/src/mult */
2531 		ppc440spe_adma_pq_set_dest(sw_desc, dst, flags);
2532 
2533 		while (src_cnt--) {
2534 			/* handle descriptors (if dst_cnt == 2) inside
2535 			 * the ppc440spe_adma_pq_set_srcxxx() functions
2536 			 */
2537 			ppc440spe_adma_pq_set_src(sw_desc, src[src_cnt],
2538 						  src_cnt);
2539 			if (!(flags & DMA_PREP_PQ_DISABLE_Q))
2540 				mult = scf[src_cnt];
2541 			ppc440spe_adma_pq_set_src_mult(sw_desc,
2542 					mult, src_cnt, dst_cnt - 1);
2543 		}
2544 	}
2545 	spin_unlock_bh(&ppc440spe_chan->lock);
2546 	ppc440spe_desc_set_rxor_block_size(len);
2547 	return sw_desc;
2548 }
2549 
2550 /**
2551  * ppc440spe_adma_prep_dma_pq - prepare CDB (group) for a GF-XOR operation
2552  */
2553 static struct dma_async_tx_descriptor *ppc440spe_adma_prep_dma_pq(
2554 		struct dma_chan *chan, dma_addr_t *dst, dma_addr_t *src,
2555 		unsigned int src_cnt, const unsigned char *scf,
2556 		size_t len, unsigned long flags)
2557 {
2558 	struct ppc440spe_adma_chan *ppc440spe_chan;
2559 	struct ppc440spe_adma_desc_slot *sw_desc = NULL;
2560 	int dst_cnt = 0;
2561 
2562 	ppc440spe_chan = to_ppc440spe_adma_chan(chan);
2563 
2564 	ADMA_LL_DBG(prep_dma_pq_dbg(ppc440spe_chan->device->id,
2565 				    dst, src, src_cnt));
2566 	BUG_ON(!len);
2567 	BUG_ON(len > PPC440SPE_ADMA_XOR_MAX_BYTE_COUNT);
2568 	BUG_ON(!src_cnt);
2569 
2570 	if (src_cnt == 1 && dst[1] == src[0]) {
2571 		dma_addr_t dest[2];
2572 
2573 		/* dst[1] is real destination (Q) */
2574 		dest[0] = dst[1];
2575 		/* this is the page to multicast source data to */
2576 		dest[1] = ppc440spe_chan->qdest;
2577 		sw_desc = ppc440spe_dma01_prep_mult(ppc440spe_chan,
2578 				dest, 2, src, src_cnt, scf, len, flags);
2579 		return sw_desc ? &sw_desc->async_tx : NULL;
2580 	}
2581 
2582 	if (src_cnt == 2 && dst[1] == src[1]) {
2583 		sw_desc = ppc440spe_dma01_prep_sum_product(ppc440spe_chan,
2584 					&dst[1], src, 2, scf, len, flags);
2585 		return sw_desc ? &sw_desc->async_tx : NULL;
2586 	}
2587 
2588 	if (!(flags & DMA_PREP_PQ_DISABLE_P)) {
2589 		BUG_ON(!dst[0]);
2590 		dst_cnt++;
2591 		flags |= DMA_PREP_ZERO_P;
2592 	}
2593 
2594 	if (!(flags & DMA_PREP_PQ_DISABLE_Q)) {
2595 		BUG_ON(!dst[1]);
2596 		dst_cnt++;
2597 		flags |= DMA_PREP_ZERO_Q;
2598 	}
2599 
2600 	BUG_ON(!dst_cnt);
2601 
2602 	dev_dbg(ppc440spe_chan->device->common.dev,
2603 		"ppc440spe adma%d: %s src_cnt: %d len: %u int_en: %d\n",
2604 		ppc440spe_chan->device->id, __func__, src_cnt, len,
2605 		flags & DMA_PREP_INTERRUPT ? 1 : 0);
2606 
2607 	switch (ppc440spe_chan->device->id) {
2608 	case PPC440SPE_DMA0_ID:
2609 	case PPC440SPE_DMA1_ID:
2610 		sw_desc = ppc440spe_dma01_prep_pq(ppc440spe_chan,
2611 				dst, dst_cnt, src, src_cnt, scf,
2612 				len, flags);
2613 		break;
2614 
2615 	case PPC440SPE_XOR_ID:
2616 		sw_desc = ppc440spe_dma2_prep_pq(ppc440spe_chan,
2617 				dst, dst_cnt, src, src_cnt, scf,
2618 				len, flags);
2619 		break;
2620 	}
2621 
2622 	return sw_desc ? &sw_desc->async_tx : NULL;
2623 }
2624 
2625 /**
2626  * ppc440spe_adma_prep_dma_pqzero_sum - prepare CDB group for
2627  * a PQ_ZERO_SUM operation
2628  */
2629 static struct dma_async_tx_descriptor *ppc440spe_adma_prep_dma_pqzero_sum(
2630 		struct dma_chan *chan, dma_addr_t *pq, dma_addr_t *src,
2631 		unsigned int src_cnt, const unsigned char *scf, size_t len,
2632 		enum sum_check_flags *pqres, unsigned long flags)
2633 {
2634 	struct ppc440spe_adma_chan *ppc440spe_chan;
2635 	struct ppc440spe_adma_desc_slot *sw_desc, *iter;
2636 	dma_addr_t pdest, qdest;
2637 	int slot_cnt, slots_per_op, idst, dst_cnt;
2638 
2639 	ppc440spe_chan = to_ppc440spe_adma_chan(chan);
2640 
2641 	if (flags & DMA_PREP_PQ_DISABLE_P)
2642 		pdest = 0;
2643 	else
2644 		pdest = pq[0];
2645 
2646 	if (flags & DMA_PREP_PQ_DISABLE_Q)
2647 		qdest = 0;
2648 	else
2649 		qdest = pq[1];
2650 
2651 	ADMA_LL_DBG(prep_dma_pqzero_sum_dbg(ppc440spe_chan->device->id,
2652 					    src, src_cnt, scf));
2653 
2654 	/* Always use WXOR for P/Q calculations (two destinations).
2655 	 * Need 1 or 2 extra slots to verify results are zero.
2656 	 */
2657 	idst = dst_cnt = (pdest && qdest) ? 2 : 1;
2658 
2659 	/* One additional slot per destination to clone P/Q
2660 	 * before calculation (we have to preserve destinations).
2661 	 */
2662 	slot_cnt = src_cnt + dst_cnt * 2;
2663 	slots_per_op = 1;
2664 
2665 	spin_lock_bh(&ppc440spe_chan->lock);
2666 	sw_desc = ppc440spe_adma_alloc_slots(ppc440spe_chan, slot_cnt,
2667 					     slots_per_op);
2668 	if (sw_desc) {
2669 		ppc440spe_desc_init_dma01pqzero_sum(sw_desc, dst_cnt, src_cnt);
2670 
2671 		/* Setup byte count for each slot just allocated */
2672 		sw_desc->async_tx.flags = flags;
2673 		list_for_each_entry(iter, &sw_desc->group_list, chain_node) {
2674 			ppc440spe_desc_set_byte_count(iter, ppc440spe_chan,
2675 						      len);
2676 			iter->unmap_len = len;
2677 		}
2678 
2679 		if (pdest) {
2680 			struct dma_cdb *hw_desc;
2681 			struct ppc440spe_adma_chan *chan;
2682 
2683 			iter = sw_desc->group_head;
2684 			chan = to_ppc440spe_adma_chan(iter->async_tx.chan);
2685 			memset(iter->hw_desc, 0, sizeof(struct dma_cdb));
2686 			iter->hw_next = list_entry(iter->chain_node.next,
2687 						struct ppc440spe_adma_desc_slot,
2688 						chain_node);
2689 			hw_desc = iter->hw_desc;
2690 			hw_desc->opc = DMA_CDB_OPC_MV_SG1_SG2;
2691 			iter->src_cnt = 0;
2692 			iter->dst_cnt = 0;
2693 			ppc440spe_desc_set_dest_addr(iter, chan, 0,
2694 						     ppc440spe_chan->pdest, 0);
2695 			ppc440spe_desc_set_src_addr(iter, chan, 0, 0, pdest);
2696 			ppc440spe_desc_set_byte_count(iter, ppc440spe_chan,
2697 						      len);
2698 			iter->unmap_len = 0;
2699 			/* override pdest to preserve original P */
2700 			pdest = ppc440spe_chan->pdest;
2701 		}
2702 		if (qdest) {
2703 			struct dma_cdb *hw_desc;
2704 			struct ppc440spe_adma_chan *chan;
2705 
2706 			iter = list_first_entry(&sw_desc->group_list,
2707 						struct ppc440spe_adma_desc_slot,
2708 						chain_node);
2709 			chan = to_ppc440spe_adma_chan(iter->async_tx.chan);
2710 
2711 			if (pdest) {
2712 				iter = list_entry(iter->chain_node.next,
2713 						struct ppc440spe_adma_desc_slot,
2714 						chain_node);
2715 			}
2716 
2717 			memset(iter->hw_desc, 0, sizeof(struct dma_cdb));
2718 			iter->hw_next = list_entry(iter->chain_node.next,
2719 						struct ppc440spe_adma_desc_slot,
2720 						chain_node);
2721 			hw_desc = iter->hw_desc;
2722 			hw_desc->opc = DMA_CDB_OPC_MV_SG1_SG2;
2723 			iter->src_cnt = 0;
2724 			iter->dst_cnt = 0;
2725 			ppc440spe_desc_set_dest_addr(iter, chan, 0,
2726 						     ppc440spe_chan->qdest, 0);
2727 			ppc440spe_desc_set_src_addr(iter, chan, 0, 0, qdest);
2728 			ppc440spe_desc_set_byte_count(iter, ppc440spe_chan,
2729 						      len);
2730 			iter->unmap_len = 0;
2731 			/* override qdest to preserve original Q */
2732 			qdest = ppc440spe_chan->qdest;
2733 		}
2734 
2735 		/* Setup destinations for P/Q ops */
2736 		ppc440spe_adma_pqzero_sum_set_dest(sw_desc, pdest, qdest);
2737 
2738 		/* Setup zero QWORDs into DCHECK CDBs */
2739 		idst = dst_cnt;
2740 		list_for_each_entry_reverse(iter, &sw_desc->group_list,
2741 					    chain_node) {
2742 			/*
2743 			 * The last CDB corresponds to Q-parity check,
2744 			 * the one before last CDB corresponds
2745 			 * P-parity check
2746 			 */
2747 			if (idst == DMA_DEST_MAX_NUM) {
2748 				if (idst == dst_cnt) {
2749 					set_bit(PPC440SPE_DESC_QCHECK,
2750 						&iter->flags);
2751 				} else {
2752 					set_bit(PPC440SPE_DESC_PCHECK,
2753 						&iter->flags);
2754 				}
2755 			} else {
2756 				if (qdest) {
2757 					set_bit(PPC440SPE_DESC_QCHECK,
2758 						&iter->flags);
2759 				} else {
2760 					set_bit(PPC440SPE_DESC_PCHECK,
2761 						&iter->flags);
2762 				}
2763 			}
2764 			iter->xor_check_result = pqres;
2765 
2766 			/*
2767 			 * set it to zero, if check fail then result will
2768 			 * be updated
2769 			 */
2770 			*iter->xor_check_result = 0;
2771 			ppc440spe_desc_set_dcheck(iter, ppc440spe_chan,
2772 				ppc440spe_qword);
2773 
2774 			if (!(--dst_cnt))
2775 				break;
2776 		}
2777 
2778 		/* Setup sources and mults for P/Q ops */
2779 		list_for_each_entry_continue_reverse(iter, &sw_desc->group_list,
2780 						     chain_node) {
2781 			struct ppc440spe_adma_chan *chan;
2782 			u32 mult_dst;
2783 
2784 			chan = to_ppc440spe_adma_chan(iter->async_tx.chan);
2785 			ppc440spe_desc_set_src_addr(iter, chan, 0,
2786 						    DMA_CUED_XOR_HB,
2787 						    src[src_cnt - 1]);
2788 			if (qdest) {
2789 				mult_dst = (dst_cnt - 1) ? DMA_CDB_SG_DST2 :
2790 							   DMA_CDB_SG_DST1;
2791 				ppc440spe_desc_set_src_mult(iter, chan,
2792 							    DMA_CUED_MULT1_OFF,
2793 							    mult_dst,
2794 							    scf[src_cnt - 1]);
2795 			}
2796 			if (!(--src_cnt))
2797 				break;
2798 		}
2799 	}
2800 	spin_unlock_bh(&ppc440spe_chan->lock);
2801 	return sw_desc ? &sw_desc->async_tx : NULL;
2802 }
2803 
2804 /**
2805  * ppc440spe_adma_prep_dma_xor_zero_sum - prepare CDB group for
2806  * XOR ZERO_SUM operation
2807  */
2808 static struct dma_async_tx_descriptor *ppc440spe_adma_prep_dma_xor_zero_sum(
2809 		struct dma_chan *chan, dma_addr_t *src, unsigned int src_cnt,
2810 		size_t len, enum sum_check_flags *result, unsigned long flags)
2811 {
2812 	struct dma_async_tx_descriptor *tx;
2813 	dma_addr_t pq[2];
2814 
2815 	/* validate P, disable Q */
2816 	pq[0] = src[0];
2817 	pq[1] = 0;
2818 	flags |= DMA_PREP_PQ_DISABLE_Q;
2819 
2820 	tx = ppc440spe_adma_prep_dma_pqzero_sum(chan, pq, &src[1],
2821 						src_cnt - 1, 0, len,
2822 						result, flags);
2823 	return tx;
2824 }
2825 
2826 /**
2827  * ppc440spe_adma_set_dest - set destination address into descriptor
2828  */
2829 static void ppc440spe_adma_set_dest(struct ppc440spe_adma_desc_slot *sw_desc,
2830 		dma_addr_t addr, int index)
2831 {
2832 	struct ppc440spe_adma_chan *chan;
2833 
2834 	BUG_ON(index >= sw_desc->dst_cnt);
2835 
2836 	chan = to_ppc440spe_adma_chan(sw_desc->async_tx.chan);
2837 
2838 	switch (chan->device->id) {
2839 	case PPC440SPE_DMA0_ID:
2840 	case PPC440SPE_DMA1_ID:
2841 		/* to do: support transfers lengths >
2842 		 * PPC440SPE_ADMA_DMA/XOR_MAX_BYTE_COUNT
2843 		 */
2844 		ppc440spe_desc_set_dest_addr(sw_desc->group_head,
2845 			chan, 0, addr, index);
2846 		break;
2847 	case PPC440SPE_XOR_ID:
2848 		sw_desc = ppc440spe_get_group_entry(sw_desc, index);
2849 		ppc440spe_desc_set_dest_addr(sw_desc,
2850 			chan, 0, addr, index);
2851 		break;
2852 	}
2853 }
2854 
2855 static void ppc440spe_adma_pq_zero_op(struct ppc440spe_adma_desc_slot *iter,
2856 		struct ppc440spe_adma_chan *chan, dma_addr_t addr)
2857 {
2858 	/*  To clear destinations update the descriptor
2859 	 * (P or Q depending on index) as follows:
2860 	 * addr is destination (0 corresponds to SG2):
2861 	 */
2862 	ppc440spe_desc_set_dest_addr(iter, chan, DMA_CUED_XOR_BASE, addr, 0);
2863 
2864 	/* ... and the addr is source: */
2865 	ppc440spe_desc_set_src_addr(iter, chan, 0, DMA_CUED_XOR_HB, addr);
2866 
2867 	/* addr is always SG2 then the mult is always DST1 */
2868 	ppc440spe_desc_set_src_mult(iter, chan, DMA_CUED_MULT1_OFF,
2869 				    DMA_CDB_SG_DST1, 1);
2870 }
2871 
2872 /**
2873  * ppc440spe_adma_pq_set_dest - set destination address into descriptor
2874  * for the PQXOR operation
2875  */
2876 static void ppc440spe_adma_pq_set_dest(struct ppc440spe_adma_desc_slot *sw_desc,
2877 		dma_addr_t *addrs, unsigned long flags)
2878 {
2879 	struct ppc440spe_adma_desc_slot *iter;
2880 	struct ppc440spe_adma_chan *chan;
2881 	dma_addr_t paddr, qaddr;
2882 	dma_addr_t addr = 0, ppath, qpath;
2883 	int index = 0, i;
2884 
2885 	chan = to_ppc440spe_adma_chan(sw_desc->async_tx.chan);
2886 
2887 	if (flags & DMA_PREP_PQ_DISABLE_P)
2888 		paddr = 0;
2889 	else
2890 		paddr = addrs[0];
2891 
2892 	if (flags & DMA_PREP_PQ_DISABLE_Q)
2893 		qaddr = 0;
2894 	else
2895 		qaddr = addrs[1];
2896 
2897 	if (!paddr || !qaddr)
2898 		addr = paddr ? paddr : qaddr;
2899 
2900 	switch (chan->device->id) {
2901 	case PPC440SPE_DMA0_ID:
2902 	case PPC440SPE_DMA1_ID:
2903 		/* walk through the WXOR source list and set P/Q-destinations
2904 		 * for each slot:
2905 		 */
2906 		if (!test_bit(PPC440SPE_DESC_RXOR, &sw_desc->flags)) {
2907 			/* This is WXOR-only chain; may have 1/2 zero descs */
2908 			if (test_bit(PPC440SPE_ZERO_P, &sw_desc->flags))
2909 				index++;
2910 			if (test_bit(PPC440SPE_ZERO_Q, &sw_desc->flags))
2911 				index++;
2912 
2913 			iter = ppc440spe_get_group_entry(sw_desc, index);
2914 			if (addr) {
2915 				/* one destination */
2916 				list_for_each_entry_from(iter,
2917 					&sw_desc->group_list, chain_node)
2918 					ppc440spe_desc_set_dest_addr(iter, chan,
2919 						DMA_CUED_XOR_BASE, addr, 0);
2920 			} else {
2921 				/* two destinations */
2922 				list_for_each_entry_from(iter,
2923 					&sw_desc->group_list, chain_node) {
2924 					ppc440spe_desc_set_dest_addr(iter, chan,
2925 						DMA_CUED_XOR_BASE, paddr, 0);
2926 					ppc440spe_desc_set_dest_addr(iter, chan,
2927 						DMA_CUED_XOR_BASE, qaddr, 1);
2928 				}
2929 			}
2930 
2931 			if (index) {
2932 				/*  To clear destinations update the descriptor
2933 				 * (1st,2nd, or both depending on flags)
2934 				 */
2935 				index = 0;
2936 				if (test_bit(PPC440SPE_ZERO_P,
2937 						&sw_desc->flags)) {
2938 					iter = ppc440spe_get_group_entry(
2939 							sw_desc, index++);
2940 					ppc440spe_adma_pq_zero_op(iter, chan,
2941 							paddr);
2942 				}
2943 
2944 				if (test_bit(PPC440SPE_ZERO_Q,
2945 						&sw_desc->flags)) {
2946 					iter = ppc440spe_get_group_entry(
2947 							sw_desc, index++);
2948 					ppc440spe_adma_pq_zero_op(iter, chan,
2949 							qaddr);
2950 				}
2951 
2952 				return;
2953 			}
2954 		} else {
2955 			/* This is RXOR-only or RXOR/WXOR mixed chain */
2956 
2957 			/* If we want to include destination into calculations,
2958 			 * then make dest addresses cued with mult=1 (XOR).
2959 			 */
2960 			ppath = test_bit(PPC440SPE_ZERO_P, &sw_desc->flags) ?
2961 					DMA_CUED_XOR_HB :
2962 					DMA_CUED_XOR_BASE |
2963 						(1 << DMA_CUED_MULT1_OFF);
2964 			qpath = test_bit(PPC440SPE_ZERO_Q, &sw_desc->flags) ?
2965 					DMA_CUED_XOR_HB :
2966 					DMA_CUED_XOR_BASE |
2967 						(1 << DMA_CUED_MULT1_OFF);
2968 
2969 			/* Setup destination(s) in RXOR slot(s) */
2970 			iter = ppc440spe_get_group_entry(sw_desc, index++);
2971 			ppc440spe_desc_set_dest_addr(iter, chan,
2972 						paddr ? ppath : qpath,
2973 						paddr ? paddr : qaddr, 0);
2974 			if (!addr) {
2975 				/* two destinations */
2976 				iter = ppc440spe_get_group_entry(sw_desc,
2977 								 index++);
2978 				ppc440spe_desc_set_dest_addr(iter, chan,
2979 						qpath, qaddr, 0);
2980 			}
2981 
2982 			if (test_bit(PPC440SPE_DESC_WXOR, &sw_desc->flags)) {
2983 				/* Setup destination(s) in remaining WXOR
2984 				 * slots
2985 				 */
2986 				iter = ppc440spe_get_group_entry(sw_desc,
2987 								 index);
2988 				if (addr) {
2989 					/* one destination */
2990 					list_for_each_entry_from(iter,
2991 					    &sw_desc->group_list,
2992 					    chain_node)
2993 						ppc440spe_desc_set_dest_addr(
2994 							iter, chan,
2995 							DMA_CUED_XOR_BASE,
2996 							addr, 0);
2997 
2998 				} else {
2999 					/* two destinations */
3000 					list_for_each_entry_from(iter,
3001 					    &sw_desc->group_list,
3002 					    chain_node) {
3003 						ppc440spe_desc_set_dest_addr(
3004 							iter, chan,
3005 							DMA_CUED_XOR_BASE,
3006 							paddr, 0);
3007 						ppc440spe_desc_set_dest_addr(
3008 							iter, chan,
3009 							DMA_CUED_XOR_BASE,
3010 							qaddr, 1);
3011 					}
3012 				}
3013 			}
3014 
3015 		}
3016 		break;
3017 
3018 	case PPC440SPE_XOR_ID:
3019 		/* DMA2 descriptors have only 1 destination, so there are
3020 		 * two chains - one for each dest.
3021 		 * If we want to include destination into calculations,
3022 		 * then make dest addresses cued with mult=1 (XOR).
3023 		 */
3024 		ppath = test_bit(PPC440SPE_ZERO_P, &sw_desc->flags) ?
3025 				DMA_CUED_XOR_HB :
3026 				DMA_CUED_XOR_BASE |
3027 					(1 << DMA_CUED_MULT1_OFF);
3028 
3029 		qpath = test_bit(PPC440SPE_ZERO_Q, &sw_desc->flags) ?
3030 				DMA_CUED_XOR_HB :
3031 				DMA_CUED_XOR_BASE |
3032 					(1 << DMA_CUED_MULT1_OFF);
3033 
3034 		iter = ppc440spe_get_group_entry(sw_desc, 0);
3035 		for (i = 0; i < sw_desc->descs_per_op; i++) {
3036 			ppc440spe_desc_set_dest_addr(iter, chan,
3037 				paddr ? ppath : qpath,
3038 				paddr ? paddr : qaddr, 0);
3039 			iter = list_entry(iter->chain_node.next,
3040 					  struct ppc440spe_adma_desc_slot,
3041 					  chain_node);
3042 		}
3043 
3044 		if (!addr) {
3045 			/* Two destinations; setup Q here */
3046 			iter = ppc440spe_get_group_entry(sw_desc,
3047 				sw_desc->descs_per_op);
3048 			for (i = 0; i < sw_desc->descs_per_op; i++) {
3049 				ppc440spe_desc_set_dest_addr(iter,
3050 					chan, qpath, qaddr, 0);
3051 				iter = list_entry(iter->chain_node.next,
3052 						struct ppc440spe_adma_desc_slot,
3053 						chain_node);
3054 			}
3055 		}
3056 
3057 		break;
3058 	}
3059 }
3060 
3061 /**
3062  * ppc440spe_adma_pq_zero_sum_set_dest - set destination address into descriptor
3063  * for the PQ_ZERO_SUM operation
3064  */
3065 static void ppc440spe_adma_pqzero_sum_set_dest(
3066 		struct ppc440spe_adma_desc_slot *sw_desc,
3067 		dma_addr_t paddr, dma_addr_t qaddr)
3068 {
3069 	struct ppc440spe_adma_desc_slot *iter, *end;
3070 	struct ppc440spe_adma_chan *chan;
3071 	dma_addr_t addr = 0;
3072 	int idx;
3073 
3074 	chan = to_ppc440spe_adma_chan(sw_desc->async_tx.chan);
3075 
3076 	/* walk through the WXOR source list and set P/Q-destinations
3077 	 * for each slot
3078 	 */
3079 	idx = (paddr && qaddr) ? 2 : 1;
3080 	/* set end */
3081 	list_for_each_entry_reverse(end, &sw_desc->group_list,
3082 				    chain_node) {
3083 		if (!(--idx))
3084 			break;
3085 	}
3086 	/* set start */
3087 	idx = (paddr && qaddr) ? 2 : 1;
3088 	iter = ppc440spe_get_group_entry(sw_desc, idx);
3089 
3090 	if (paddr && qaddr) {
3091 		/* two destinations */
3092 		list_for_each_entry_from(iter, &sw_desc->group_list,
3093 					 chain_node) {
3094 			if (unlikely(iter == end))
3095 				break;
3096 			ppc440spe_desc_set_dest_addr(iter, chan,
3097 						DMA_CUED_XOR_BASE, paddr, 0);
3098 			ppc440spe_desc_set_dest_addr(iter, chan,
3099 						DMA_CUED_XOR_BASE, qaddr, 1);
3100 		}
3101 	} else {
3102 		/* one destination */
3103 		addr = paddr ? paddr : qaddr;
3104 		list_for_each_entry_from(iter, &sw_desc->group_list,
3105 					 chain_node) {
3106 			if (unlikely(iter == end))
3107 				break;
3108 			ppc440spe_desc_set_dest_addr(iter, chan,
3109 						DMA_CUED_XOR_BASE, addr, 0);
3110 		}
3111 	}
3112 
3113 	/*  The remaining descriptors are DATACHECK. These have no need in
3114 	 * destination. Actually, these destinations are used there
3115 	 * as sources for check operation. So, set addr as source.
3116 	 */
3117 	ppc440spe_desc_set_src_addr(end, chan, 0, 0, addr ? addr : paddr);
3118 
3119 	if (!addr) {
3120 		end = list_entry(end->chain_node.next,
3121 				 struct ppc440spe_adma_desc_slot, chain_node);
3122 		ppc440spe_desc_set_src_addr(end, chan, 0, 0, qaddr);
3123 	}
3124 }
3125 
3126 /**
3127  * ppc440spe_desc_set_xor_src_cnt - set source count into descriptor
3128  */
3129 static inline void ppc440spe_desc_set_xor_src_cnt(
3130 			struct ppc440spe_adma_desc_slot *desc,
3131 			int src_cnt)
3132 {
3133 	struct xor_cb *hw_desc = desc->hw_desc;
3134 
3135 	hw_desc->cbc &= ~XOR_CDCR_OAC_MSK;
3136 	hw_desc->cbc |= src_cnt;
3137 }
3138 
3139 /**
3140  * ppc440spe_adma_pq_set_src - set source address into descriptor
3141  */
3142 static void ppc440spe_adma_pq_set_src(struct ppc440spe_adma_desc_slot *sw_desc,
3143 		dma_addr_t addr, int index)
3144 {
3145 	struct ppc440spe_adma_chan *chan;
3146 	dma_addr_t haddr = 0;
3147 	struct ppc440spe_adma_desc_slot *iter = NULL;
3148 
3149 	chan = to_ppc440spe_adma_chan(sw_desc->async_tx.chan);
3150 
3151 	switch (chan->device->id) {
3152 	case PPC440SPE_DMA0_ID:
3153 	case PPC440SPE_DMA1_ID:
3154 		/* DMA0,1 may do: WXOR, RXOR, RXOR+WXORs chain
3155 		 */
3156 		if (test_bit(PPC440SPE_DESC_RXOR, &sw_desc->flags)) {
3157 			/* RXOR-only or RXOR/WXOR operation */
3158 			int iskip = test_bit(PPC440SPE_DESC_RXOR12,
3159 				&sw_desc->flags) ?  2 : 3;
3160 
3161 			if (index == 0) {
3162 				/* 1st slot (RXOR) */
3163 				/* setup sources region (R1-2-3, R1-2-4,
3164 				 * or R1-2-5)
3165 				 */
3166 				if (test_bit(PPC440SPE_DESC_RXOR12,
3167 						&sw_desc->flags))
3168 					haddr = DMA_RXOR12 <<
3169 						DMA_CUED_REGION_OFF;
3170 				else if (test_bit(PPC440SPE_DESC_RXOR123,
3171 				    &sw_desc->flags))
3172 					haddr = DMA_RXOR123 <<
3173 						DMA_CUED_REGION_OFF;
3174 				else if (test_bit(PPC440SPE_DESC_RXOR124,
3175 				    &sw_desc->flags))
3176 					haddr = DMA_RXOR124 <<
3177 						DMA_CUED_REGION_OFF;
3178 				else if (test_bit(PPC440SPE_DESC_RXOR125,
3179 				    &sw_desc->flags))
3180 					haddr = DMA_RXOR125 <<
3181 						DMA_CUED_REGION_OFF;
3182 				else
3183 					BUG();
3184 				haddr |= DMA_CUED_XOR_BASE;
3185 				iter = ppc440spe_get_group_entry(sw_desc, 0);
3186 			} else if (index < iskip) {
3187 				/* 1st slot (RXOR)
3188 				 * shall actually set source address only once
3189 				 * instead of first <iskip>
3190 				 */
3191 				iter = NULL;
3192 			} else {
3193 				/* 2nd/3d and next slots (WXOR);
3194 				 * skip first slot with RXOR
3195 				 */
3196 				haddr = DMA_CUED_XOR_HB;
3197 				iter = ppc440spe_get_group_entry(sw_desc,
3198 				    index - iskip + sw_desc->dst_cnt);
3199 			}
3200 		} else {
3201 			int znum = 0;
3202 
3203 			/* WXOR-only operation; skip first slots with
3204 			 * zeroing destinations
3205 			 */
3206 			if (test_bit(PPC440SPE_ZERO_P, &sw_desc->flags))
3207 				znum++;
3208 			if (test_bit(PPC440SPE_ZERO_Q, &sw_desc->flags))
3209 				znum++;
3210 
3211 			haddr = DMA_CUED_XOR_HB;
3212 			iter = ppc440spe_get_group_entry(sw_desc,
3213 					index + znum);
3214 		}
3215 
3216 		if (likely(iter)) {
3217 			ppc440spe_desc_set_src_addr(iter, chan, 0, haddr, addr);
3218 
3219 			if (!index &&
3220 			    test_bit(PPC440SPE_DESC_RXOR, &sw_desc->flags) &&
3221 			    sw_desc->dst_cnt == 2) {
3222 				/* if we have two destinations for RXOR, then
3223 				 * setup source in the second descr too
3224 				 */
3225 				iter = ppc440spe_get_group_entry(sw_desc, 1);
3226 				ppc440spe_desc_set_src_addr(iter, chan, 0,
3227 					haddr, addr);
3228 			}
3229 		}
3230 		break;
3231 
3232 	case PPC440SPE_XOR_ID:
3233 		/* DMA2 may do Biskup */
3234 		iter = sw_desc->group_head;
3235 		if (iter->dst_cnt == 2) {
3236 			/* both P & Q calculations required; set P src here */
3237 			ppc440spe_adma_dma2rxor_set_src(iter, index, addr);
3238 
3239 			/* this is for Q */
3240 			iter = ppc440spe_get_group_entry(sw_desc,
3241 				sw_desc->descs_per_op);
3242 		}
3243 		ppc440spe_adma_dma2rxor_set_src(iter, index, addr);
3244 		break;
3245 	}
3246 }
3247 
3248 /**
3249  * ppc440spe_adma_memcpy_xor_set_src - set source address into descriptor
3250  */
3251 static void ppc440spe_adma_memcpy_xor_set_src(
3252 		struct ppc440spe_adma_desc_slot *sw_desc,
3253 		dma_addr_t addr, int index)
3254 {
3255 	struct ppc440spe_adma_chan *chan;
3256 
3257 	chan = to_ppc440spe_adma_chan(sw_desc->async_tx.chan);
3258 	sw_desc = sw_desc->group_head;
3259 
3260 	if (likely(sw_desc))
3261 		ppc440spe_desc_set_src_addr(sw_desc, chan, index, 0, addr);
3262 }
3263 
3264 /**
3265  * ppc440spe_adma_dma2rxor_inc_addr  -
3266  */
3267 static void ppc440spe_adma_dma2rxor_inc_addr(
3268 		struct ppc440spe_adma_desc_slot *desc,
3269 		struct ppc440spe_rxor *cursor, int index, int src_cnt)
3270 {
3271 	cursor->addr_count++;
3272 	if (index == src_cnt - 1) {
3273 		ppc440spe_desc_set_xor_src_cnt(desc, cursor->addr_count);
3274 	} else if (cursor->addr_count == XOR_MAX_OPS) {
3275 		ppc440spe_desc_set_xor_src_cnt(desc, cursor->addr_count);
3276 		cursor->addr_count = 0;
3277 		cursor->desc_count++;
3278 	}
3279 }
3280 
3281 /**
3282  * ppc440spe_adma_dma2rxor_prep_src - setup RXOR types in DMA2 CDB
3283  */
3284 static int ppc440spe_adma_dma2rxor_prep_src(
3285 		struct ppc440spe_adma_desc_slot *hdesc,
3286 		struct ppc440spe_rxor *cursor, int index,
3287 		int src_cnt, u32 addr)
3288 {
3289 	int rval = 0;
3290 	u32 sign;
3291 	struct ppc440spe_adma_desc_slot *desc = hdesc;
3292 	int i;
3293 
3294 	for (i = 0; i < cursor->desc_count; i++) {
3295 		desc = list_entry(hdesc->chain_node.next,
3296 				  struct ppc440spe_adma_desc_slot,
3297 				  chain_node);
3298 	}
3299 
3300 	switch (cursor->state) {
3301 	case 0:
3302 		if (addr == cursor->addrl + cursor->len) {
3303 			/* direct RXOR */
3304 			cursor->state = 1;
3305 			cursor->xor_count++;
3306 			if (index == src_cnt-1) {
3307 				ppc440spe_rxor_set_region(desc,
3308 					cursor->addr_count,
3309 					DMA_RXOR12 << DMA_CUED_REGION_OFF);
3310 				ppc440spe_adma_dma2rxor_inc_addr(
3311 					desc, cursor, index, src_cnt);
3312 			}
3313 		} else if (cursor->addrl == addr + cursor->len) {
3314 			/* reverse RXOR */
3315 			cursor->state = 1;
3316 			cursor->xor_count++;
3317 			set_bit(cursor->addr_count, &desc->reverse_flags[0]);
3318 			if (index == src_cnt-1) {
3319 				ppc440spe_rxor_set_region(desc,
3320 					cursor->addr_count,
3321 					DMA_RXOR12 << DMA_CUED_REGION_OFF);
3322 				ppc440spe_adma_dma2rxor_inc_addr(
3323 					desc, cursor, index, src_cnt);
3324 			}
3325 		} else {
3326 			printk(KERN_ERR "Cannot build "
3327 				"DMA2 RXOR command block.\n");
3328 			BUG();
3329 		}
3330 		break;
3331 	case 1:
3332 		sign = test_bit(cursor->addr_count,
3333 				desc->reverse_flags)
3334 			? -1 : 1;
3335 		if (index == src_cnt-2 || (sign == -1
3336 			&& addr != cursor->addrl - 2*cursor->len)) {
3337 			cursor->state = 0;
3338 			cursor->xor_count = 1;
3339 			cursor->addrl = addr;
3340 			ppc440spe_rxor_set_region(desc,
3341 				cursor->addr_count,
3342 				DMA_RXOR12 << DMA_CUED_REGION_OFF);
3343 			ppc440spe_adma_dma2rxor_inc_addr(
3344 				desc, cursor, index, src_cnt);
3345 		} else if (addr == cursor->addrl + 2*sign*cursor->len) {
3346 			cursor->state = 2;
3347 			cursor->xor_count = 0;
3348 			ppc440spe_rxor_set_region(desc,
3349 				cursor->addr_count,
3350 				DMA_RXOR123 << DMA_CUED_REGION_OFF);
3351 			if (index == src_cnt-1) {
3352 				ppc440spe_adma_dma2rxor_inc_addr(
3353 					desc, cursor, index, src_cnt);
3354 			}
3355 		} else if (addr == cursor->addrl + 3*cursor->len) {
3356 			cursor->state = 2;
3357 			cursor->xor_count = 0;
3358 			ppc440spe_rxor_set_region(desc,
3359 				cursor->addr_count,
3360 				DMA_RXOR124 << DMA_CUED_REGION_OFF);
3361 			if (index == src_cnt-1) {
3362 				ppc440spe_adma_dma2rxor_inc_addr(
3363 					desc, cursor, index, src_cnt);
3364 			}
3365 		} else if (addr == cursor->addrl + 4*cursor->len) {
3366 			cursor->state = 2;
3367 			cursor->xor_count = 0;
3368 			ppc440spe_rxor_set_region(desc,
3369 				cursor->addr_count,
3370 				DMA_RXOR125 << DMA_CUED_REGION_OFF);
3371 			if (index == src_cnt-1) {
3372 				ppc440spe_adma_dma2rxor_inc_addr(
3373 					desc, cursor, index, src_cnt);
3374 			}
3375 		} else {
3376 			cursor->state = 0;
3377 			cursor->xor_count = 1;
3378 			cursor->addrl = addr;
3379 			ppc440spe_rxor_set_region(desc,
3380 				cursor->addr_count,
3381 				DMA_RXOR12 << DMA_CUED_REGION_OFF);
3382 			ppc440spe_adma_dma2rxor_inc_addr(
3383 				desc, cursor, index, src_cnt);
3384 		}
3385 		break;
3386 	case 2:
3387 		cursor->state = 0;
3388 		cursor->addrl = addr;
3389 		cursor->xor_count++;
3390 		if (index) {
3391 			ppc440spe_adma_dma2rxor_inc_addr(
3392 				desc, cursor, index, src_cnt);
3393 		}
3394 		break;
3395 	}
3396 
3397 	return rval;
3398 }
3399 
3400 /**
3401  * ppc440spe_adma_dma2rxor_set_src - set RXOR source address; it's assumed that
3402  *	ppc440spe_adma_dma2rxor_prep_src() has already done prior this call
3403  */
3404 static void ppc440spe_adma_dma2rxor_set_src(
3405 		struct ppc440spe_adma_desc_slot *desc,
3406 		int index, dma_addr_t addr)
3407 {
3408 	struct xor_cb *xcb = desc->hw_desc;
3409 	int k = 0, op = 0, lop = 0;
3410 
3411 	/* get the RXOR operand which corresponds to index addr */
3412 	while (op <= index) {
3413 		lop = op;
3414 		if (k == XOR_MAX_OPS) {
3415 			k = 0;
3416 			desc = list_entry(desc->chain_node.next,
3417 				struct ppc440spe_adma_desc_slot, chain_node);
3418 			xcb = desc->hw_desc;
3419 
3420 		}
3421 		if ((xcb->ops[k++].h & (DMA_RXOR12 << DMA_CUED_REGION_OFF)) ==
3422 		    (DMA_RXOR12 << DMA_CUED_REGION_OFF))
3423 			op += 2;
3424 		else
3425 			op += 3;
3426 	}
3427 
3428 	BUG_ON(k < 1);
3429 
3430 	if (test_bit(k-1, desc->reverse_flags)) {
3431 		/* reverse operand order; put last op in RXOR group */
3432 		if (index == op - 1)
3433 			ppc440spe_rxor_set_src(desc, k - 1, addr);
3434 	} else {
3435 		/* direct operand order; put first op in RXOR group */
3436 		if (index == lop)
3437 			ppc440spe_rxor_set_src(desc, k - 1, addr);
3438 	}
3439 }
3440 
3441 /**
3442  * ppc440spe_adma_dma2rxor_set_mult - set RXOR multipliers; it's assumed that
3443  *	ppc440spe_adma_dma2rxor_prep_src() has already done prior this call
3444  */
3445 static void ppc440spe_adma_dma2rxor_set_mult(
3446 		struct ppc440spe_adma_desc_slot *desc,
3447 		int index, u8 mult)
3448 {
3449 	struct xor_cb *xcb = desc->hw_desc;
3450 	int k = 0, op = 0, lop = 0;
3451 
3452 	/* get the RXOR operand which corresponds to index mult */
3453 	while (op <= index) {
3454 		lop = op;
3455 		if (k == XOR_MAX_OPS) {
3456 			k = 0;
3457 			desc = list_entry(desc->chain_node.next,
3458 					  struct ppc440spe_adma_desc_slot,
3459 					  chain_node);
3460 			xcb = desc->hw_desc;
3461 
3462 		}
3463 		if ((xcb->ops[k++].h & (DMA_RXOR12 << DMA_CUED_REGION_OFF)) ==
3464 		    (DMA_RXOR12 << DMA_CUED_REGION_OFF))
3465 			op += 2;
3466 		else
3467 			op += 3;
3468 	}
3469 
3470 	BUG_ON(k < 1);
3471 	if (test_bit(k-1, desc->reverse_flags)) {
3472 		/* reverse order */
3473 		ppc440spe_rxor_set_mult(desc, k - 1, op - index - 1, mult);
3474 	} else {
3475 		/* direct order */
3476 		ppc440spe_rxor_set_mult(desc, k - 1, index - lop, mult);
3477 	}
3478 }
3479 
3480 /**
3481  * ppc440spe_init_rxor_cursor -
3482  */
3483 static void ppc440spe_init_rxor_cursor(struct ppc440spe_rxor *cursor)
3484 {
3485 	memset(cursor, 0, sizeof(struct ppc440spe_rxor));
3486 	cursor->state = 2;
3487 }
3488 
3489 /**
3490  * ppc440spe_adma_pq_set_src_mult - set multiplication coefficient into
3491  * descriptor for the PQXOR operation
3492  */
3493 static void ppc440spe_adma_pq_set_src_mult(
3494 		struct ppc440spe_adma_desc_slot *sw_desc,
3495 		unsigned char mult, int index, int dst_pos)
3496 {
3497 	struct ppc440spe_adma_chan *chan;
3498 	u32 mult_idx, mult_dst;
3499 	struct ppc440spe_adma_desc_slot *iter = NULL, *iter1 = NULL;
3500 
3501 	chan = to_ppc440spe_adma_chan(sw_desc->async_tx.chan);
3502 
3503 	switch (chan->device->id) {
3504 	case PPC440SPE_DMA0_ID:
3505 	case PPC440SPE_DMA1_ID:
3506 		if (test_bit(PPC440SPE_DESC_RXOR, &sw_desc->flags)) {
3507 			int region = test_bit(PPC440SPE_DESC_RXOR12,
3508 					&sw_desc->flags) ? 2 : 3;
3509 
3510 			if (index < region) {
3511 				/* RXOR multipliers */
3512 				iter = ppc440spe_get_group_entry(sw_desc,
3513 					sw_desc->dst_cnt - 1);
3514 				if (sw_desc->dst_cnt == 2)
3515 					iter1 = ppc440spe_get_group_entry(
3516 							sw_desc, 0);
3517 
3518 				mult_idx = DMA_CUED_MULT1_OFF + (index << 3);
3519 				mult_dst = DMA_CDB_SG_SRC;
3520 			} else {
3521 				/* WXOR multiplier */
3522 				iter = ppc440spe_get_group_entry(sw_desc,
3523 							index - region +
3524 							sw_desc->dst_cnt);
3525 				mult_idx = DMA_CUED_MULT1_OFF;
3526 				mult_dst = dst_pos ? DMA_CDB_SG_DST2 :
3527 						     DMA_CDB_SG_DST1;
3528 			}
3529 		} else {
3530 			int znum = 0;
3531 
3532 			/* WXOR-only;
3533 			 * skip first slots with destinations (if ZERO_DST has
3534 			 * place)
3535 			 */
3536 			if (test_bit(PPC440SPE_ZERO_P, &sw_desc->flags))
3537 				znum++;
3538 			if (test_bit(PPC440SPE_ZERO_Q, &sw_desc->flags))
3539 				znum++;
3540 
3541 			iter = ppc440spe_get_group_entry(sw_desc, index + znum);
3542 			mult_idx = DMA_CUED_MULT1_OFF;
3543 			mult_dst = dst_pos ? DMA_CDB_SG_DST2 : DMA_CDB_SG_DST1;
3544 		}
3545 
3546 		if (likely(iter)) {
3547 			ppc440spe_desc_set_src_mult(iter, chan,
3548 				mult_idx, mult_dst, mult);
3549 
3550 			if (unlikely(iter1)) {
3551 				/* if we have two destinations for RXOR, then
3552 				 * we've just set Q mult. Set-up P now.
3553 				 */
3554 				ppc440spe_desc_set_src_mult(iter1, chan,
3555 					mult_idx, mult_dst, 1);
3556 			}
3557 
3558 		}
3559 		break;
3560 
3561 	case PPC440SPE_XOR_ID:
3562 		iter = sw_desc->group_head;
3563 		if (sw_desc->dst_cnt == 2) {
3564 			/* both P & Q calculations required; set P mult here */
3565 			ppc440spe_adma_dma2rxor_set_mult(iter, index, 1);
3566 
3567 			/* and then set Q mult */
3568 			iter = ppc440spe_get_group_entry(sw_desc,
3569 			       sw_desc->descs_per_op);
3570 		}
3571 		ppc440spe_adma_dma2rxor_set_mult(iter, index, mult);
3572 		break;
3573 	}
3574 }
3575 
3576 /**
3577  * ppc440spe_adma_free_chan_resources - free the resources allocated
3578  */
3579 static void ppc440spe_adma_free_chan_resources(struct dma_chan *chan)
3580 {
3581 	struct ppc440spe_adma_chan *ppc440spe_chan;
3582 	struct ppc440spe_adma_desc_slot *iter, *_iter;
3583 	int in_use_descs = 0;
3584 
3585 	ppc440spe_chan = to_ppc440spe_adma_chan(chan);
3586 	ppc440spe_adma_slot_cleanup(ppc440spe_chan);
3587 
3588 	spin_lock_bh(&ppc440spe_chan->lock);
3589 	list_for_each_entry_safe(iter, _iter, &ppc440spe_chan->chain,
3590 					chain_node) {
3591 		in_use_descs++;
3592 		list_del(&iter->chain_node);
3593 	}
3594 	list_for_each_entry_safe_reverse(iter, _iter,
3595 			&ppc440spe_chan->all_slots, slot_node) {
3596 		list_del(&iter->slot_node);
3597 		kfree(iter);
3598 		ppc440spe_chan->slots_allocated--;
3599 	}
3600 	ppc440spe_chan->last_used = NULL;
3601 
3602 	dev_dbg(ppc440spe_chan->device->common.dev,
3603 		"ppc440spe adma%d %s slots_allocated %d\n",
3604 		ppc440spe_chan->device->id,
3605 		__func__, ppc440spe_chan->slots_allocated);
3606 	spin_unlock_bh(&ppc440spe_chan->lock);
3607 
3608 	/* one is ok since we left it on there on purpose */
3609 	if (in_use_descs > 1)
3610 		printk(KERN_ERR "SPE: Freeing %d in use descriptors!\n",
3611 			in_use_descs - 1);
3612 }
3613 
3614 /**
3615  * ppc440spe_adma_tx_status - poll the status of an ADMA transaction
3616  * @chan: ADMA channel handle
3617  * @cookie: ADMA transaction identifier
3618  * @txstate: a holder for the current state of the channel
3619  */
3620 static enum dma_status ppc440spe_adma_tx_status(struct dma_chan *chan,
3621 			dma_cookie_t cookie, struct dma_tx_state *txstate)
3622 {
3623 	struct ppc440spe_adma_chan *ppc440spe_chan;
3624 	enum dma_status ret;
3625 
3626 	ppc440spe_chan = to_ppc440spe_adma_chan(chan);
3627 	ret = dma_cookie_status(chan, cookie, txstate);
3628 	if (ret == DMA_COMPLETE)
3629 		return ret;
3630 
3631 	ppc440spe_adma_slot_cleanup(ppc440spe_chan);
3632 
3633 	return dma_cookie_status(chan, cookie, txstate);
3634 }
3635 
3636 /**
3637  * ppc440spe_adma_eot_handler - end of transfer interrupt handler
3638  */
3639 static irqreturn_t ppc440spe_adma_eot_handler(int irq, void *data)
3640 {
3641 	struct ppc440spe_adma_chan *chan = data;
3642 
3643 	dev_dbg(chan->device->common.dev,
3644 		"ppc440spe adma%d: %s\n", chan->device->id, __func__);
3645 
3646 	tasklet_schedule(&chan->irq_tasklet);
3647 	ppc440spe_adma_device_clear_eot_status(chan);
3648 
3649 	return IRQ_HANDLED;
3650 }
3651 
3652 /**
3653  * ppc440spe_adma_err_handler - DMA error interrupt handler;
3654  *	do the same things as a eot handler
3655  */
3656 static irqreturn_t ppc440spe_adma_err_handler(int irq, void *data)
3657 {
3658 	struct ppc440spe_adma_chan *chan = data;
3659 
3660 	dev_dbg(chan->device->common.dev,
3661 		"ppc440spe adma%d: %s\n", chan->device->id, __func__);
3662 
3663 	tasklet_schedule(&chan->irq_tasklet);
3664 	ppc440spe_adma_device_clear_eot_status(chan);
3665 
3666 	return IRQ_HANDLED;
3667 }
3668 
3669 /**
3670  * ppc440spe_test_callback - called when test operation has been done
3671  */
3672 static void ppc440spe_test_callback(void *unused)
3673 {
3674 	complete(&ppc440spe_r6_test_comp);
3675 }
3676 
3677 /**
3678  * ppc440spe_adma_issue_pending - flush all pending descriptors to h/w
3679  */
3680 static void ppc440spe_adma_issue_pending(struct dma_chan *chan)
3681 {
3682 	struct ppc440spe_adma_chan *ppc440spe_chan;
3683 
3684 	ppc440spe_chan = to_ppc440spe_adma_chan(chan);
3685 	dev_dbg(ppc440spe_chan->device->common.dev,
3686 		"ppc440spe adma%d: %s %d \n", ppc440spe_chan->device->id,
3687 		__func__, ppc440spe_chan->pending);
3688 
3689 	if (ppc440spe_chan->pending) {
3690 		ppc440spe_chan->pending = 0;
3691 		ppc440spe_chan_append(ppc440spe_chan);
3692 	}
3693 }
3694 
3695 /**
3696  * ppc440spe_chan_start_null_xor - initiate the first XOR operation (DMA engines
3697  *	use FIFOs (as opposite to chains used in XOR) so this is a XOR
3698  *	specific operation)
3699  */
3700 static void ppc440spe_chan_start_null_xor(struct ppc440spe_adma_chan *chan)
3701 {
3702 	struct ppc440spe_adma_desc_slot *sw_desc, *group_start;
3703 	dma_cookie_t cookie;
3704 	int slot_cnt, slots_per_op;
3705 
3706 	dev_dbg(chan->device->common.dev,
3707 		"ppc440spe adma%d: %s\n", chan->device->id, __func__);
3708 
3709 	spin_lock_bh(&chan->lock);
3710 	slot_cnt = ppc440spe_chan_xor_slot_count(0, 2, &slots_per_op);
3711 	sw_desc = ppc440spe_adma_alloc_slots(chan, slot_cnt, slots_per_op);
3712 	if (sw_desc) {
3713 		group_start = sw_desc->group_head;
3714 		list_splice_init(&sw_desc->group_list, &chan->chain);
3715 		async_tx_ack(&sw_desc->async_tx);
3716 		ppc440spe_desc_init_null_xor(group_start);
3717 
3718 		cookie = dma_cookie_assign(&sw_desc->async_tx);
3719 
3720 		/* initialize the completed cookie to be less than
3721 		 * the most recently used cookie
3722 		 */
3723 		chan->common.completed_cookie = cookie - 1;
3724 
3725 		/* channel should not be busy */
3726 		BUG_ON(ppc440spe_chan_is_busy(chan));
3727 
3728 		/* set the descriptor address */
3729 		ppc440spe_chan_set_first_xor_descriptor(chan, sw_desc);
3730 
3731 		/* run the descriptor */
3732 		ppc440spe_chan_run(chan);
3733 	} else
3734 		printk(KERN_ERR "ppc440spe adma%d"
3735 			" failed to allocate null descriptor\n",
3736 			chan->device->id);
3737 	spin_unlock_bh(&chan->lock);
3738 }
3739 
3740 /**
3741  * ppc440spe_test_raid6 - test are RAID-6 capabilities enabled successfully.
3742  *	For this we just perform one WXOR operation with the same source
3743  *	and destination addresses, the GF-multiplier is 1; so if RAID-6
3744  *	capabilities are enabled then we'll get src/dst filled with zero.
3745  */
3746 static int ppc440spe_test_raid6(struct ppc440spe_adma_chan *chan)
3747 {
3748 	struct ppc440spe_adma_desc_slot *sw_desc, *iter;
3749 	struct page *pg;
3750 	char *a;
3751 	dma_addr_t dma_addr, addrs[2];
3752 	unsigned long op = 0;
3753 	int rval = 0;
3754 
3755 	set_bit(PPC440SPE_DESC_WXOR, &op);
3756 
3757 	pg = alloc_page(GFP_KERNEL);
3758 	if (!pg)
3759 		return -ENOMEM;
3760 
3761 	spin_lock_bh(&chan->lock);
3762 	sw_desc = ppc440spe_adma_alloc_slots(chan, 1, 1);
3763 	if (sw_desc) {
3764 		/* 1 src, 1 dsr, int_ena, WXOR */
3765 		ppc440spe_desc_init_dma01pq(sw_desc, 1, 1, 1, op);
3766 		list_for_each_entry(iter, &sw_desc->group_list, chain_node) {
3767 			ppc440spe_desc_set_byte_count(iter, chan, PAGE_SIZE);
3768 			iter->unmap_len = PAGE_SIZE;
3769 		}
3770 	} else {
3771 		rval = -EFAULT;
3772 		spin_unlock_bh(&chan->lock);
3773 		goto exit;
3774 	}
3775 	spin_unlock_bh(&chan->lock);
3776 
3777 	/* Fill the test page with ones */
3778 	memset(page_address(pg), 0xFF, PAGE_SIZE);
3779 	dma_addr = dma_map_page(chan->device->dev, pg, 0,
3780 				PAGE_SIZE, DMA_BIDIRECTIONAL);
3781 
3782 	/* Setup addresses */
3783 	ppc440spe_adma_pq_set_src(sw_desc, dma_addr, 0);
3784 	ppc440spe_adma_pq_set_src_mult(sw_desc, 1, 0, 0);
3785 	addrs[0] = dma_addr;
3786 	addrs[1] = 0;
3787 	ppc440spe_adma_pq_set_dest(sw_desc, addrs, DMA_PREP_PQ_DISABLE_Q);
3788 
3789 	async_tx_ack(&sw_desc->async_tx);
3790 	sw_desc->async_tx.callback = ppc440spe_test_callback;
3791 	sw_desc->async_tx.callback_param = NULL;
3792 
3793 	init_completion(&ppc440spe_r6_test_comp);
3794 
3795 	ppc440spe_adma_tx_submit(&sw_desc->async_tx);
3796 	ppc440spe_adma_issue_pending(&chan->common);
3797 
3798 	wait_for_completion(&ppc440spe_r6_test_comp);
3799 
3800 	/* Now check if the test page is zeroed */
3801 	a = page_address(pg);
3802 	if ((*(u32 *)a) == 0 && memcmp(a, a+4, PAGE_SIZE-4) == 0) {
3803 		/* page is zero - RAID-6 enabled */
3804 		rval = 0;
3805 	} else {
3806 		/* RAID-6 was not enabled */
3807 		rval = -EINVAL;
3808 	}
3809 exit:
3810 	__free_page(pg);
3811 	return rval;
3812 }
3813 
3814 static void ppc440spe_adma_init_capabilities(struct ppc440spe_adma_device *adev)
3815 {
3816 	switch (adev->id) {
3817 	case PPC440SPE_DMA0_ID:
3818 	case PPC440SPE_DMA1_ID:
3819 		dma_cap_set(DMA_MEMCPY, adev->common.cap_mask);
3820 		dma_cap_set(DMA_INTERRUPT, adev->common.cap_mask);
3821 		dma_cap_set(DMA_PQ, adev->common.cap_mask);
3822 		dma_cap_set(DMA_PQ_VAL, adev->common.cap_mask);
3823 		dma_cap_set(DMA_XOR_VAL, adev->common.cap_mask);
3824 		break;
3825 	case PPC440SPE_XOR_ID:
3826 		dma_cap_set(DMA_XOR, adev->common.cap_mask);
3827 		dma_cap_set(DMA_PQ, adev->common.cap_mask);
3828 		dma_cap_set(DMA_INTERRUPT, adev->common.cap_mask);
3829 		adev->common.cap_mask = adev->common.cap_mask;
3830 		break;
3831 	}
3832 
3833 	/* Set base routines */
3834 	adev->common.device_alloc_chan_resources =
3835 				ppc440spe_adma_alloc_chan_resources;
3836 	adev->common.device_free_chan_resources =
3837 				ppc440spe_adma_free_chan_resources;
3838 	adev->common.device_tx_status = ppc440spe_adma_tx_status;
3839 	adev->common.device_issue_pending = ppc440spe_adma_issue_pending;
3840 
3841 	/* Set prep routines based on capability */
3842 	if (dma_has_cap(DMA_MEMCPY, adev->common.cap_mask)) {
3843 		adev->common.device_prep_dma_memcpy =
3844 			ppc440spe_adma_prep_dma_memcpy;
3845 	}
3846 	if (dma_has_cap(DMA_XOR, adev->common.cap_mask)) {
3847 		adev->common.max_xor = XOR_MAX_OPS;
3848 		adev->common.device_prep_dma_xor =
3849 			ppc440spe_adma_prep_dma_xor;
3850 	}
3851 	if (dma_has_cap(DMA_PQ, adev->common.cap_mask)) {
3852 		switch (adev->id) {
3853 		case PPC440SPE_DMA0_ID:
3854 			dma_set_maxpq(&adev->common,
3855 				DMA0_FIFO_SIZE / sizeof(struct dma_cdb), 0);
3856 			break;
3857 		case PPC440SPE_DMA1_ID:
3858 			dma_set_maxpq(&adev->common,
3859 				DMA1_FIFO_SIZE / sizeof(struct dma_cdb), 0);
3860 			break;
3861 		case PPC440SPE_XOR_ID:
3862 			adev->common.max_pq = XOR_MAX_OPS * 3;
3863 			break;
3864 		}
3865 		adev->common.device_prep_dma_pq =
3866 			ppc440spe_adma_prep_dma_pq;
3867 	}
3868 	if (dma_has_cap(DMA_PQ_VAL, adev->common.cap_mask)) {
3869 		switch (adev->id) {
3870 		case PPC440SPE_DMA0_ID:
3871 			adev->common.max_pq = DMA0_FIFO_SIZE /
3872 						sizeof(struct dma_cdb);
3873 			break;
3874 		case PPC440SPE_DMA1_ID:
3875 			adev->common.max_pq = DMA1_FIFO_SIZE /
3876 						sizeof(struct dma_cdb);
3877 			break;
3878 		}
3879 		adev->common.device_prep_dma_pq_val =
3880 			ppc440spe_adma_prep_dma_pqzero_sum;
3881 	}
3882 	if (dma_has_cap(DMA_XOR_VAL, adev->common.cap_mask)) {
3883 		switch (adev->id) {
3884 		case PPC440SPE_DMA0_ID:
3885 			adev->common.max_xor = DMA0_FIFO_SIZE /
3886 						sizeof(struct dma_cdb);
3887 			break;
3888 		case PPC440SPE_DMA1_ID:
3889 			adev->common.max_xor = DMA1_FIFO_SIZE /
3890 						sizeof(struct dma_cdb);
3891 			break;
3892 		}
3893 		adev->common.device_prep_dma_xor_val =
3894 			ppc440spe_adma_prep_dma_xor_zero_sum;
3895 	}
3896 	if (dma_has_cap(DMA_INTERRUPT, adev->common.cap_mask)) {
3897 		adev->common.device_prep_dma_interrupt =
3898 			ppc440spe_adma_prep_dma_interrupt;
3899 	}
3900 	pr_info("%s: AMCC(R) PPC440SP(E) ADMA Engine: "
3901 	  "( %s%s%s%s%s%s%s)\n",
3902 	  dev_name(adev->dev),
3903 	  dma_has_cap(DMA_PQ, adev->common.cap_mask) ? "pq " : "",
3904 	  dma_has_cap(DMA_PQ_VAL, adev->common.cap_mask) ? "pq_val " : "",
3905 	  dma_has_cap(DMA_XOR, adev->common.cap_mask) ? "xor " : "",
3906 	  dma_has_cap(DMA_XOR_VAL, adev->common.cap_mask) ? "xor_val " : "",
3907 	  dma_has_cap(DMA_MEMCPY, adev->common.cap_mask) ? "memcpy " : "",
3908 	  dma_has_cap(DMA_INTERRUPT, adev->common.cap_mask) ? "intr " : "");
3909 }
3910 
3911 static int ppc440spe_adma_setup_irqs(struct ppc440spe_adma_device *adev,
3912 				     struct ppc440spe_adma_chan *chan,
3913 				     int *initcode)
3914 {
3915 	struct platform_device *ofdev;
3916 	struct device_node *np;
3917 	int ret;
3918 
3919 	ofdev = container_of(adev->dev, struct platform_device, dev);
3920 	np = ofdev->dev.of_node;
3921 	if (adev->id != PPC440SPE_XOR_ID) {
3922 		adev->err_irq = irq_of_parse_and_map(np, 1);
3923 		if (adev->err_irq == NO_IRQ) {
3924 			dev_warn(adev->dev, "no err irq resource?\n");
3925 			*initcode = PPC_ADMA_INIT_IRQ2;
3926 			adev->err_irq = -ENXIO;
3927 		} else
3928 			atomic_inc(&ppc440spe_adma_err_irq_ref);
3929 	} else {
3930 		adev->err_irq = -ENXIO;
3931 	}
3932 
3933 	adev->irq = irq_of_parse_and_map(np, 0);
3934 	if (adev->irq == NO_IRQ) {
3935 		dev_err(adev->dev, "no irq resource\n");
3936 		*initcode = PPC_ADMA_INIT_IRQ1;
3937 		ret = -ENXIO;
3938 		goto err_irq_map;
3939 	}
3940 	dev_dbg(adev->dev, "irq %d, err irq %d\n",
3941 		adev->irq, adev->err_irq);
3942 
3943 	ret = request_irq(adev->irq, ppc440spe_adma_eot_handler,
3944 			  0, dev_driver_string(adev->dev), chan);
3945 	if (ret) {
3946 		dev_err(adev->dev, "can't request irq %d\n",
3947 			adev->irq);
3948 		*initcode = PPC_ADMA_INIT_IRQ1;
3949 		ret = -EIO;
3950 		goto err_req1;
3951 	}
3952 
3953 	/* only DMA engines have a separate error IRQ
3954 	 * so it's Ok if err_irq < 0 in XOR engine case.
3955 	 */
3956 	if (adev->err_irq > 0) {
3957 		/* both DMA engines share common error IRQ */
3958 		ret = request_irq(adev->err_irq,
3959 				  ppc440spe_adma_err_handler,
3960 				  IRQF_SHARED,
3961 				  dev_driver_string(adev->dev),
3962 				  chan);
3963 		if (ret) {
3964 			dev_err(adev->dev, "can't request irq %d\n",
3965 				adev->err_irq);
3966 			*initcode = PPC_ADMA_INIT_IRQ2;
3967 			ret = -EIO;
3968 			goto err_req2;
3969 		}
3970 	}
3971 
3972 	if (adev->id == PPC440SPE_XOR_ID) {
3973 		/* enable XOR engine interrupts */
3974 		iowrite32be(XOR_IE_CBCIE_BIT | XOR_IE_ICBIE_BIT |
3975 			    XOR_IE_ICIE_BIT | XOR_IE_RPTIE_BIT,
3976 			    &adev->xor_reg->ier);
3977 	} else {
3978 		u32 mask, enable;
3979 
3980 		np = of_find_compatible_node(NULL, NULL, "ibm,i2o-440spe");
3981 		if (!np) {
3982 			pr_err("%s: can't find I2O device tree node\n",
3983 				__func__);
3984 			ret = -ENODEV;
3985 			goto err_req2;
3986 		}
3987 		adev->i2o_reg = of_iomap(np, 0);
3988 		if (!adev->i2o_reg) {
3989 			pr_err("%s: failed to map I2O registers\n", __func__);
3990 			of_node_put(np);
3991 			ret = -EINVAL;
3992 			goto err_req2;
3993 		}
3994 		of_node_put(np);
3995 		/* Unmask 'CS FIFO Attention' interrupts and
3996 		 * enable generating interrupts on errors
3997 		 */
3998 		enable = (adev->id == PPC440SPE_DMA0_ID) ?
3999 			 ~(I2O_IOPIM_P0SNE | I2O_IOPIM_P0EM) :
4000 			 ~(I2O_IOPIM_P1SNE | I2O_IOPIM_P1EM);
4001 		mask = ioread32(&adev->i2o_reg->iopim) & enable;
4002 		iowrite32(mask, &adev->i2o_reg->iopim);
4003 	}
4004 	return 0;
4005 
4006 err_req2:
4007 	free_irq(adev->irq, chan);
4008 err_req1:
4009 	irq_dispose_mapping(adev->irq);
4010 err_irq_map:
4011 	if (adev->err_irq > 0) {
4012 		if (atomic_dec_and_test(&ppc440spe_adma_err_irq_ref))
4013 			irq_dispose_mapping(adev->err_irq);
4014 	}
4015 	return ret;
4016 }
4017 
4018 static void ppc440spe_adma_release_irqs(struct ppc440spe_adma_device *adev,
4019 					struct ppc440spe_adma_chan *chan)
4020 {
4021 	u32 mask, disable;
4022 
4023 	if (adev->id == PPC440SPE_XOR_ID) {
4024 		/* disable XOR engine interrupts */
4025 		mask = ioread32be(&adev->xor_reg->ier);
4026 		mask &= ~(XOR_IE_CBCIE_BIT | XOR_IE_ICBIE_BIT |
4027 			  XOR_IE_ICIE_BIT | XOR_IE_RPTIE_BIT);
4028 		iowrite32be(mask, &adev->xor_reg->ier);
4029 	} else {
4030 		/* disable DMAx engine interrupts */
4031 		disable = (adev->id == PPC440SPE_DMA0_ID) ?
4032 			  (I2O_IOPIM_P0SNE | I2O_IOPIM_P0EM) :
4033 			  (I2O_IOPIM_P1SNE | I2O_IOPIM_P1EM);
4034 		mask = ioread32(&adev->i2o_reg->iopim) | disable;
4035 		iowrite32(mask, &adev->i2o_reg->iopim);
4036 	}
4037 	free_irq(adev->irq, chan);
4038 	irq_dispose_mapping(adev->irq);
4039 	if (adev->err_irq > 0) {
4040 		free_irq(adev->err_irq, chan);
4041 		if (atomic_dec_and_test(&ppc440spe_adma_err_irq_ref)) {
4042 			irq_dispose_mapping(adev->err_irq);
4043 			iounmap(adev->i2o_reg);
4044 		}
4045 	}
4046 }
4047 
4048 /**
4049  * ppc440spe_adma_probe - probe the asynch device
4050  */
4051 static int ppc440spe_adma_probe(struct platform_device *ofdev)
4052 {
4053 	struct device_node *np = ofdev->dev.of_node;
4054 	struct resource res;
4055 	struct ppc440spe_adma_device *adev;
4056 	struct ppc440spe_adma_chan *chan;
4057 	struct ppc_dma_chan_ref *ref, *_ref;
4058 	int ret = 0, initcode = PPC_ADMA_INIT_OK;
4059 	const u32 *idx;
4060 	int len;
4061 	void *regs;
4062 	u32 id, pool_size;
4063 
4064 	if (of_device_is_compatible(np, "amcc,xor-accelerator")) {
4065 		id = PPC440SPE_XOR_ID;
4066 		/* As far as the XOR engine is concerned, it does not
4067 		 * use FIFOs but uses linked list. So there is no dependency
4068 		 * between pool size to allocate and the engine configuration.
4069 		 */
4070 		pool_size = PAGE_SIZE << 1;
4071 	} else {
4072 		/* it is DMA0 or DMA1 */
4073 		idx = of_get_property(np, "cell-index", &len);
4074 		if (!idx || (len != sizeof(u32))) {
4075 			dev_err(&ofdev->dev, "Device node %s has missing "
4076 				"or invalid cell-index property\n",
4077 				np->full_name);
4078 			return -EINVAL;
4079 		}
4080 		id = *idx;
4081 		/* DMA0,1 engines use FIFO to maintain CDBs, so we
4082 		 * should allocate the pool accordingly to size of this
4083 		 * FIFO. Thus, the pool size depends on the FIFO depth:
4084 		 * how much CDBs pointers the FIFO may contain then so
4085 		 * much CDBs we should provide in the pool.
4086 		 * That is
4087 		 *   CDB size = 32B;
4088 		 *   CDBs number = (DMA0_FIFO_SIZE >> 3);
4089 		 *   Pool size = CDBs number * CDB size =
4090 		 *      = (DMA0_FIFO_SIZE >> 3) << 5 = DMA0_FIFO_SIZE << 2.
4091 		 */
4092 		pool_size = (id == PPC440SPE_DMA0_ID) ?
4093 			    DMA0_FIFO_SIZE : DMA1_FIFO_SIZE;
4094 		pool_size <<= 2;
4095 	}
4096 
4097 	if (of_address_to_resource(np, 0, &res)) {
4098 		dev_err(&ofdev->dev, "failed to get memory resource\n");
4099 		initcode = PPC_ADMA_INIT_MEMRES;
4100 		ret = -ENODEV;
4101 		goto out;
4102 	}
4103 
4104 	if (!request_mem_region(res.start, resource_size(&res),
4105 				dev_driver_string(&ofdev->dev))) {
4106 		dev_err(&ofdev->dev, "failed to request memory region %pR\n",
4107 			&res);
4108 		initcode = PPC_ADMA_INIT_MEMREG;
4109 		ret = -EBUSY;
4110 		goto out;
4111 	}
4112 
4113 	/* create a device */
4114 	adev = kzalloc(sizeof(*adev), GFP_KERNEL);
4115 	if (!adev) {
4116 		dev_err(&ofdev->dev, "failed to allocate device\n");
4117 		initcode = PPC_ADMA_INIT_ALLOC;
4118 		ret = -ENOMEM;
4119 		goto err_adev_alloc;
4120 	}
4121 
4122 	adev->id = id;
4123 	adev->pool_size = pool_size;
4124 	/* allocate coherent memory for hardware descriptors */
4125 	adev->dma_desc_pool_virt = dma_alloc_coherent(&ofdev->dev,
4126 					adev->pool_size, &adev->dma_desc_pool,
4127 					GFP_KERNEL);
4128 	if (adev->dma_desc_pool_virt == NULL) {
4129 		dev_err(&ofdev->dev, "failed to allocate %d bytes of coherent "
4130 			"memory for hardware descriptors\n",
4131 			adev->pool_size);
4132 		initcode = PPC_ADMA_INIT_COHERENT;
4133 		ret = -ENOMEM;
4134 		goto err_dma_alloc;
4135 	}
4136 	dev_dbg(&ofdev->dev, "allocated descriptor pool virt 0x%p phys 0x%llx\n",
4137 		adev->dma_desc_pool_virt, (u64)adev->dma_desc_pool);
4138 
4139 	regs = ioremap(res.start, resource_size(&res));
4140 	if (!regs) {
4141 		dev_err(&ofdev->dev, "failed to ioremap regs!\n");
4142 		goto err_regs_alloc;
4143 	}
4144 
4145 	if (adev->id == PPC440SPE_XOR_ID) {
4146 		adev->xor_reg = regs;
4147 		/* Reset XOR */
4148 		iowrite32be(XOR_CRSR_XASR_BIT, &adev->xor_reg->crsr);
4149 		iowrite32be(XOR_CRSR_64BA_BIT, &adev->xor_reg->crrr);
4150 	} else {
4151 		size_t fifo_size = (adev->id == PPC440SPE_DMA0_ID) ?
4152 				   DMA0_FIFO_SIZE : DMA1_FIFO_SIZE;
4153 		adev->dma_reg = regs;
4154 		/* DMAx_FIFO_SIZE is defined in bytes,
4155 		 * <fsiz> - is defined in number of CDB pointers (8byte).
4156 		 * DMA FIFO Length = CSlength + CPlength, where
4157 		 * CSlength = CPlength = (fsiz + 1) * 8.
4158 		 */
4159 		iowrite32(DMA_FIFO_ENABLE | ((fifo_size >> 3) - 2),
4160 			  &adev->dma_reg->fsiz);
4161 		/* Configure DMA engine */
4162 		iowrite32(DMA_CFG_DXEPR_HP | DMA_CFG_DFMPP_HP | DMA_CFG_FALGN,
4163 			  &adev->dma_reg->cfg);
4164 		/* Clear Status */
4165 		iowrite32(~0, &adev->dma_reg->dsts);
4166 	}
4167 
4168 	adev->dev = &ofdev->dev;
4169 	adev->common.dev = &ofdev->dev;
4170 	INIT_LIST_HEAD(&adev->common.channels);
4171 	platform_set_drvdata(ofdev, adev);
4172 
4173 	/* create a channel */
4174 	chan = kzalloc(sizeof(*chan), GFP_KERNEL);
4175 	if (!chan) {
4176 		dev_err(&ofdev->dev, "can't allocate channel structure\n");
4177 		initcode = PPC_ADMA_INIT_CHANNEL;
4178 		ret = -ENOMEM;
4179 		goto err_chan_alloc;
4180 	}
4181 
4182 	spin_lock_init(&chan->lock);
4183 	INIT_LIST_HEAD(&chan->chain);
4184 	INIT_LIST_HEAD(&chan->all_slots);
4185 	chan->device = adev;
4186 	chan->common.device = &adev->common;
4187 	dma_cookie_init(&chan->common);
4188 	list_add_tail(&chan->common.device_node, &adev->common.channels);
4189 	tasklet_init(&chan->irq_tasklet, ppc440spe_adma_tasklet,
4190 		     (unsigned long)chan);
4191 
4192 	/* allocate and map helper pages for async validation or
4193 	 * async_mult/async_sum_product operations on DMA0/1.
4194 	 */
4195 	if (adev->id != PPC440SPE_XOR_ID) {
4196 		chan->pdest_page = alloc_page(GFP_KERNEL);
4197 		chan->qdest_page = alloc_page(GFP_KERNEL);
4198 		if (!chan->pdest_page ||
4199 		    !chan->qdest_page) {
4200 			if (chan->pdest_page)
4201 				__free_page(chan->pdest_page);
4202 			if (chan->qdest_page)
4203 				__free_page(chan->qdest_page);
4204 			ret = -ENOMEM;
4205 			goto err_page_alloc;
4206 		}
4207 		chan->pdest = dma_map_page(&ofdev->dev, chan->pdest_page, 0,
4208 					   PAGE_SIZE, DMA_BIDIRECTIONAL);
4209 		chan->qdest = dma_map_page(&ofdev->dev, chan->qdest_page, 0,
4210 					   PAGE_SIZE, DMA_BIDIRECTIONAL);
4211 	}
4212 
4213 	ref = kmalloc(sizeof(*ref), GFP_KERNEL);
4214 	if (ref) {
4215 		ref->chan = &chan->common;
4216 		INIT_LIST_HEAD(&ref->node);
4217 		list_add_tail(&ref->node, &ppc440spe_adma_chan_list);
4218 	} else {
4219 		dev_err(&ofdev->dev, "failed to allocate channel reference!\n");
4220 		ret = -ENOMEM;
4221 		goto err_ref_alloc;
4222 	}
4223 
4224 	ret = ppc440spe_adma_setup_irqs(adev, chan, &initcode);
4225 	if (ret)
4226 		goto err_irq;
4227 
4228 	ppc440spe_adma_init_capabilities(adev);
4229 
4230 	ret = dma_async_device_register(&adev->common);
4231 	if (ret) {
4232 		initcode = PPC_ADMA_INIT_REGISTER;
4233 		dev_err(&ofdev->dev, "failed to register dma device\n");
4234 		goto err_dev_reg;
4235 	}
4236 
4237 	goto out;
4238 
4239 err_dev_reg:
4240 	ppc440spe_adma_release_irqs(adev, chan);
4241 err_irq:
4242 	list_for_each_entry_safe(ref, _ref, &ppc440spe_adma_chan_list, node) {
4243 		if (chan == to_ppc440spe_adma_chan(ref->chan)) {
4244 			list_del(&ref->node);
4245 			kfree(ref);
4246 		}
4247 	}
4248 err_ref_alloc:
4249 	if (adev->id != PPC440SPE_XOR_ID) {
4250 		dma_unmap_page(&ofdev->dev, chan->pdest,
4251 			       PAGE_SIZE, DMA_BIDIRECTIONAL);
4252 		dma_unmap_page(&ofdev->dev, chan->qdest,
4253 			       PAGE_SIZE, DMA_BIDIRECTIONAL);
4254 		__free_page(chan->pdest_page);
4255 		__free_page(chan->qdest_page);
4256 	}
4257 err_page_alloc:
4258 	kfree(chan);
4259 err_chan_alloc:
4260 	if (adev->id == PPC440SPE_XOR_ID)
4261 		iounmap(adev->xor_reg);
4262 	else
4263 		iounmap(adev->dma_reg);
4264 err_regs_alloc:
4265 	dma_free_coherent(adev->dev, adev->pool_size,
4266 			  adev->dma_desc_pool_virt,
4267 			  adev->dma_desc_pool);
4268 err_dma_alloc:
4269 	kfree(adev);
4270 err_adev_alloc:
4271 	release_mem_region(res.start, resource_size(&res));
4272 out:
4273 	if (id < PPC440SPE_ADMA_ENGINES_NUM)
4274 		ppc440spe_adma_devices[id] = initcode;
4275 
4276 	return ret;
4277 }
4278 
4279 /**
4280  * ppc440spe_adma_remove - remove the asynch device
4281  */
4282 static int ppc440spe_adma_remove(struct platform_device *ofdev)
4283 {
4284 	struct ppc440spe_adma_device *adev = platform_get_drvdata(ofdev);
4285 	struct device_node *np = ofdev->dev.of_node;
4286 	struct resource res;
4287 	struct dma_chan *chan, *_chan;
4288 	struct ppc_dma_chan_ref *ref, *_ref;
4289 	struct ppc440spe_adma_chan *ppc440spe_chan;
4290 
4291 	if (adev->id < PPC440SPE_ADMA_ENGINES_NUM)
4292 		ppc440spe_adma_devices[adev->id] = -1;
4293 
4294 	dma_async_device_unregister(&adev->common);
4295 
4296 	list_for_each_entry_safe(chan, _chan, &adev->common.channels,
4297 				 device_node) {
4298 		ppc440spe_chan = to_ppc440spe_adma_chan(chan);
4299 		ppc440spe_adma_release_irqs(adev, ppc440spe_chan);
4300 		tasklet_kill(&ppc440spe_chan->irq_tasklet);
4301 		if (adev->id != PPC440SPE_XOR_ID) {
4302 			dma_unmap_page(&ofdev->dev, ppc440spe_chan->pdest,
4303 					PAGE_SIZE, DMA_BIDIRECTIONAL);
4304 			dma_unmap_page(&ofdev->dev, ppc440spe_chan->qdest,
4305 					PAGE_SIZE, DMA_BIDIRECTIONAL);
4306 			__free_page(ppc440spe_chan->pdest_page);
4307 			__free_page(ppc440spe_chan->qdest_page);
4308 		}
4309 		list_for_each_entry_safe(ref, _ref, &ppc440spe_adma_chan_list,
4310 					 node) {
4311 			if (ppc440spe_chan ==
4312 			    to_ppc440spe_adma_chan(ref->chan)) {
4313 				list_del(&ref->node);
4314 				kfree(ref);
4315 			}
4316 		}
4317 		list_del(&chan->device_node);
4318 		kfree(ppc440spe_chan);
4319 	}
4320 
4321 	dma_free_coherent(adev->dev, adev->pool_size,
4322 			  adev->dma_desc_pool_virt, adev->dma_desc_pool);
4323 	if (adev->id == PPC440SPE_XOR_ID)
4324 		iounmap(adev->xor_reg);
4325 	else
4326 		iounmap(adev->dma_reg);
4327 	of_address_to_resource(np, 0, &res);
4328 	release_mem_region(res.start, resource_size(&res));
4329 	kfree(adev);
4330 	return 0;
4331 }
4332 
4333 /*
4334  * /sys driver interface to enable h/w RAID-6 capabilities
4335  * Files created in e.g. /sys/devices/plb.0/400100100.dma0/driver/
4336  * directory are "devices", "enable" and "poly".
4337  * "devices" shows available engines.
4338  * "enable" is used to enable RAID-6 capabilities or to check
4339  * whether these has been activated.
4340  * "poly" allows setting/checking used polynomial (for PPC440SPe only).
4341  */
4342 
4343 static ssize_t show_ppc440spe_devices(struct device_driver *dev, char *buf)
4344 {
4345 	ssize_t size = 0;
4346 	int i;
4347 
4348 	for (i = 0; i < PPC440SPE_ADMA_ENGINES_NUM; i++) {
4349 		if (ppc440spe_adma_devices[i] == -1)
4350 			continue;
4351 		size += snprintf(buf + size, PAGE_SIZE - size,
4352 				 "PPC440SP(E)-ADMA.%d: %s\n", i,
4353 				 ppc_adma_errors[ppc440spe_adma_devices[i]]);
4354 	}
4355 	return size;
4356 }
4357 
4358 static ssize_t show_ppc440spe_r6enable(struct device_driver *dev, char *buf)
4359 {
4360 	return snprintf(buf, PAGE_SIZE,
4361 			"PPC440SP(e) RAID-6 capabilities are %sABLED.\n",
4362 			ppc440spe_r6_enabled ? "EN" : "DIS");
4363 }
4364 
4365 static ssize_t store_ppc440spe_r6enable(struct device_driver *dev,
4366 					const char *buf, size_t count)
4367 {
4368 	unsigned long val;
4369 
4370 	if (!count || count > 11)
4371 		return -EINVAL;
4372 
4373 	if (!ppc440spe_r6_tchan)
4374 		return -EFAULT;
4375 
4376 	/* Write a key */
4377 	sscanf(buf, "%lx", &val);
4378 	dcr_write(ppc440spe_mq_dcr_host, DCRN_MQ0_XORBA, val);
4379 	isync();
4380 
4381 	/* Verify whether it really works now */
4382 	if (ppc440spe_test_raid6(ppc440spe_r6_tchan) == 0) {
4383 		pr_info("PPC440SP(e) RAID-6 has been activated "
4384 			"successfully\n");
4385 		ppc440spe_r6_enabled = 1;
4386 	} else {
4387 		pr_info("PPC440SP(e) RAID-6 hasn't been activated!"
4388 			" Error key ?\n");
4389 		ppc440spe_r6_enabled = 0;
4390 	}
4391 	return count;
4392 }
4393 
4394 static ssize_t show_ppc440spe_r6poly(struct device_driver *dev, char *buf)
4395 {
4396 	ssize_t size = 0;
4397 	u32 reg;
4398 
4399 #ifdef CONFIG_440SP
4400 	/* 440SP has fixed polynomial */
4401 	reg = 0x4d;
4402 #else
4403 	reg = dcr_read(ppc440spe_mq_dcr_host, DCRN_MQ0_CFBHL);
4404 	reg >>= MQ0_CFBHL_POLY;
4405 	reg &= 0xFF;
4406 #endif
4407 
4408 	size = snprintf(buf, PAGE_SIZE, "PPC440SP(e) RAID-6 driver "
4409 			"uses 0x1%02x polynomial.\n", reg);
4410 	return size;
4411 }
4412 
4413 static ssize_t store_ppc440spe_r6poly(struct device_driver *dev,
4414 				      const char *buf, size_t count)
4415 {
4416 	unsigned long reg, val;
4417 
4418 #ifdef CONFIG_440SP
4419 	/* 440SP uses default 0x14D polynomial only */
4420 	return -EINVAL;
4421 #endif
4422 
4423 	if (!count || count > 6)
4424 		return -EINVAL;
4425 
4426 	/* e.g., 0x14D or 0x11D */
4427 	sscanf(buf, "%lx", &val);
4428 
4429 	if (val & ~0x1FF)
4430 		return -EINVAL;
4431 
4432 	val &= 0xFF;
4433 	reg = dcr_read(ppc440spe_mq_dcr_host, DCRN_MQ0_CFBHL);
4434 	reg &= ~(0xFF << MQ0_CFBHL_POLY);
4435 	reg |= val << MQ0_CFBHL_POLY;
4436 	dcr_write(ppc440spe_mq_dcr_host, DCRN_MQ0_CFBHL, reg);
4437 
4438 	return count;
4439 }
4440 
4441 static DRIVER_ATTR(devices, S_IRUGO, show_ppc440spe_devices, NULL);
4442 static DRIVER_ATTR(enable, S_IRUGO | S_IWUSR, show_ppc440spe_r6enable,
4443 		   store_ppc440spe_r6enable);
4444 static DRIVER_ATTR(poly, S_IRUGO | S_IWUSR, show_ppc440spe_r6poly,
4445 		   store_ppc440spe_r6poly);
4446 
4447 /*
4448  * Common initialisation for RAID engines; allocate memory for
4449  * DMAx FIFOs, perform configuration common for all DMA engines.
4450  * Further DMA engine specific configuration is done at probe time.
4451  */
4452 static int ppc440spe_configure_raid_devices(void)
4453 {
4454 	struct device_node *np;
4455 	struct resource i2o_res;
4456 	struct i2o_regs __iomem *i2o_reg;
4457 	dcr_host_t i2o_dcr_host;
4458 	unsigned int dcr_base, dcr_len;
4459 	int i, ret;
4460 
4461 	np = of_find_compatible_node(NULL, NULL, "ibm,i2o-440spe");
4462 	if (!np) {
4463 		pr_err("%s: can't find I2O device tree node\n",
4464 			__func__);
4465 		return -ENODEV;
4466 	}
4467 
4468 	if (of_address_to_resource(np, 0, &i2o_res)) {
4469 		of_node_put(np);
4470 		return -EINVAL;
4471 	}
4472 
4473 	i2o_reg = of_iomap(np, 0);
4474 	if (!i2o_reg) {
4475 		pr_err("%s: failed to map I2O registers\n", __func__);
4476 		of_node_put(np);
4477 		return -EINVAL;
4478 	}
4479 
4480 	/* Get I2O DCRs base */
4481 	dcr_base = dcr_resource_start(np, 0);
4482 	dcr_len = dcr_resource_len(np, 0);
4483 	if (!dcr_base && !dcr_len) {
4484 		pr_err("%s: can't get DCR registers base/len!\n",
4485 			np->full_name);
4486 		of_node_put(np);
4487 		iounmap(i2o_reg);
4488 		return -ENODEV;
4489 	}
4490 
4491 	i2o_dcr_host = dcr_map(np, dcr_base, dcr_len);
4492 	if (!DCR_MAP_OK(i2o_dcr_host)) {
4493 		pr_err("%s: failed to map DCRs!\n", np->full_name);
4494 		of_node_put(np);
4495 		iounmap(i2o_reg);
4496 		return -ENODEV;
4497 	}
4498 	of_node_put(np);
4499 
4500 	/* Provide memory regions for DMA's FIFOs: I2O, DMA0 and DMA1 share
4501 	 * the base address of FIFO memory space.
4502 	 * Actually we need twice more physical memory than programmed in the
4503 	 * <fsiz> register (because there are two FIFOs for each DMA: CP and CS)
4504 	 */
4505 	ppc440spe_dma_fifo_buf = kmalloc((DMA0_FIFO_SIZE + DMA1_FIFO_SIZE) << 1,
4506 					 GFP_KERNEL);
4507 	if (!ppc440spe_dma_fifo_buf) {
4508 		pr_err("%s: DMA FIFO buffer allocation failed.\n", __func__);
4509 		iounmap(i2o_reg);
4510 		dcr_unmap(i2o_dcr_host, dcr_len);
4511 		return -ENOMEM;
4512 	}
4513 
4514 	/*
4515 	 * Configure h/w
4516 	 */
4517 	/* Reset I2O/DMA */
4518 	mtdcri(SDR0, DCRN_SDR0_SRST, DCRN_SDR0_SRST_I2ODMA);
4519 	mtdcri(SDR0, DCRN_SDR0_SRST, 0);
4520 
4521 	/* Setup the base address of mmaped registers */
4522 	dcr_write(i2o_dcr_host, DCRN_I2O0_IBAH, (u32)(i2o_res.start >> 32));
4523 	dcr_write(i2o_dcr_host, DCRN_I2O0_IBAL, (u32)(i2o_res.start) |
4524 						I2O_REG_ENABLE);
4525 	dcr_unmap(i2o_dcr_host, dcr_len);
4526 
4527 	/* Setup FIFO memory space base address */
4528 	iowrite32(0, &i2o_reg->ifbah);
4529 	iowrite32(((u32)__pa(ppc440spe_dma_fifo_buf)), &i2o_reg->ifbal);
4530 
4531 	/* set zero FIFO size for I2O, so the whole
4532 	 * ppc440spe_dma_fifo_buf is used by DMAs.
4533 	 * DMAx_FIFOs will be configured while probe.
4534 	 */
4535 	iowrite32(0, &i2o_reg->ifsiz);
4536 	iounmap(i2o_reg);
4537 
4538 	/* To prepare WXOR/RXOR functionality we need access to
4539 	 * Memory Queue Module DCRs (finally it will be enabled
4540 	 * via /sys interface of the ppc440spe ADMA driver).
4541 	 */
4542 	np = of_find_compatible_node(NULL, NULL, "ibm,mq-440spe");
4543 	if (!np) {
4544 		pr_err("%s: can't find MQ device tree node\n",
4545 			__func__);
4546 		ret = -ENODEV;
4547 		goto out_free;
4548 	}
4549 
4550 	/* Get MQ DCRs base */
4551 	dcr_base = dcr_resource_start(np, 0);
4552 	dcr_len = dcr_resource_len(np, 0);
4553 	if (!dcr_base && !dcr_len) {
4554 		pr_err("%s: can't get DCR registers base/len!\n",
4555 			np->full_name);
4556 		ret = -ENODEV;
4557 		goto out_mq;
4558 	}
4559 
4560 	ppc440spe_mq_dcr_host = dcr_map(np, dcr_base, dcr_len);
4561 	if (!DCR_MAP_OK(ppc440spe_mq_dcr_host)) {
4562 		pr_err("%s: failed to map DCRs!\n", np->full_name);
4563 		ret = -ENODEV;
4564 		goto out_mq;
4565 	}
4566 	of_node_put(np);
4567 	ppc440spe_mq_dcr_len = dcr_len;
4568 
4569 	/* Set HB alias */
4570 	dcr_write(ppc440spe_mq_dcr_host, DCRN_MQ0_BAUH, DMA_CUED_XOR_HB);
4571 
4572 	/* Set:
4573 	 * - LL transaction passing limit to 1;
4574 	 * - Memory controller cycle limit to 1;
4575 	 * - Galois Polynomial to 0x14d (default)
4576 	 */
4577 	dcr_write(ppc440spe_mq_dcr_host, DCRN_MQ0_CFBHL,
4578 		  (1 << MQ0_CFBHL_TPLM) | (1 << MQ0_CFBHL_HBCL) |
4579 		  (PPC440SPE_DEFAULT_POLY << MQ0_CFBHL_POLY));
4580 
4581 	atomic_set(&ppc440spe_adma_err_irq_ref, 0);
4582 	for (i = 0; i < PPC440SPE_ADMA_ENGINES_NUM; i++)
4583 		ppc440spe_adma_devices[i] = -1;
4584 
4585 	return 0;
4586 
4587 out_mq:
4588 	of_node_put(np);
4589 out_free:
4590 	kfree(ppc440spe_dma_fifo_buf);
4591 	return ret;
4592 }
4593 
4594 static const struct of_device_id ppc440spe_adma_of_match[] = {
4595 	{ .compatible	= "ibm,dma-440spe", },
4596 	{ .compatible	= "amcc,xor-accelerator", },
4597 	{},
4598 };
4599 MODULE_DEVICE_TABLE(of, ppc440spe_adma_of_match);
4600 
4601 static struct platform_driver ppc440spe_adma_driver = {
4602 	.probe = ppc440spe_adma_probe,
4603 	.remove = ppc440spe_adma_remove,
4604 	.driver = {
4605 		.name = "PPC440SP(E)-ADMA",
4606 		.owner = THIS_MODULE,
4607 		.of_match_table = ppc440spe_adma_of_match,
4608 	},
4609 };
4610 
4611 static __init int ppc440spe_adma_init(void)
4612 {
4613 	int ret;
4614 
4615 	ret = ppc440spe_configure_raid_devices();
4616 	if (ret)
4617 		return ret;
4618 
4619 	ret = platform_driver_register(&ppc440spe_adma_driver);
4620 	if (ret) {
4621 		pr_err("%s: failed to register platform driver\n",
4622 			__func__);
4623 		goto out_reg;
4624 	}
4625 
4626 	/* Initialization status */
4627 	ret = driver_create_file(&ppc440spe_adma_driver.driver,
4628 				 &driver_attr_devices);
4629 	if (ret)
4630 		goto out_dev;
4631 
4632 	/* RAID-6 h/w enable entry */
4633 	ret = driver_create_file(&ppc440spe_adma_driver.driver,
4634 				 &driver_attr_enable);
4635 	if (ret)
4636 		goto out_en;
4637 
4638 	/* GF polynomial to use */
4639 	ret = driver_create_file(&ppc440spe_adma_driver.driver,
4640 				 &driver_attr_poly);
4641 	if (!ret)
4642 		return ret;
4643 
4644 	driver_remove_file(&ppc440spe_adma_driver.driver,
4645 			   &driver_attr_enable);
4646 out_en:
4647 	driver_remove_file(&ppc440spe_adma_driver.driver,
4648 			   &driver_attr_devices);
4649 out_dev:
4650 	/* User will not be able to enable h/w RAID-6 */
4651 	pr_err("%s: failed to create RAID-6 driver interface\n",
4652 		__func__);
4653 	platform_driver_unregister(&ppc440spe_adma_driver);
4654 out_reg:
4655 	dcr_unmap(ppc440spe_mq_dcr_host, ppc440spe_mq_dcr_len);
4656 	kfree(ppc440spe_dma_fifo_buf);
4657 	return ret;
4658 }
4659 
4660 static void __exit ppc440spe_adma_exit(void)
4661 {
4662 	driver_remove_file(&ppc440spe_adma_driver.driver,
4663 			   &driver_attr_poly);
4664 	driver_remove_file(&ppc440spe_adma_driver.driver,
4665 			   &driver_attr_enable);
4666 	driver_remove_file(&ppc440spe_adma_driver.driver,
4667 			   &driver_attr_devices);
4668 	platform_driver_unregister(&ppc440spe_adma_driver);
4669 	dcr_unmap(ppc440spe_mq_dcr_host, ppc440spe_mq_dcr_len);
4670 	kfree(ppc440spe_dma_fifo_buf);
4671 }
4672 
4673 arch_initcall(ppc440spe_adma_init);
4674 module_exit(ppc440spe_adma_exit);
4675 
4676 MODULE_AUTHOR("Yuri Tikhonov <yur@emcraft.com>");
4677 MODULE_DESCRIPTION("PPC440SPE ADMA Engine Driver");
4678 MODULE_LICENSE("GPL");
4679