xref: /openbmc/linux/drivers/dma/ppc4xx/adma.c (revision 2c64e9cb)
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  * The full GNU General Public License is included in this distribution in the
20  * file called COPYING.
21  */
22 
23 /*
24  * This driver supports the asynchrounous DMA copy and RAID engines available
25  * on the AMCC PPC440SPe Processors.
26  * Based on the Intel Xscale(R) family of I/O Processors (IOP 32x, 33x, 134x)
27  * ADMA driver written by D.Williams.
28  */
29 
30 #include <linux/init.h>
31 #include <linux/module.h>
32 #include <linux/async_tx.h>
33 #include <linux/delay.h>
34 #include <linux/dma-mapping.h>
35 #include <linux/spinlock.h>
36 #include <linux/interrupt.h>
37 #include <linux/slab.h>
38 #include <linux/uaccess.h>
39 #include <linux/proc_fs.h>
40 #include <linux/of.h>
41 #include <linux/of_address.h>
42 #include <linux/of_irq.h>
43 #include <linux/of_platform.h>
44 #include <asm/dcr.h>
45 #include <asm/dcr-regs.h>
46 #include "adma.h"
47 #include "../dmaengine.h"
48 
49 enum ppc_adma_init_code {
50 	PPC_ADMA_INIT_OK = 0,
51 	PPC_ADMA_INIT_MEMRES,
52 	PPC_ADMA_INIT_MEMREG,
53 	PPC_ADMA_INIT_ALLOC,
54 	PPC_ADMA_INIT_COHERENT,
55 	PPC_ADMA_INIT_CHANNEL,
56 	PPC_ADMA_INIT_IRQ1,
57 	PPC_ADMA_INIT_IRQ2,
58 	PPC_ADMA_INIT_REGISTER
59 };
60 
61 static char *ppc_adma_errors[] = {
62 	[PPC_ADMA_INIT_OK] = "ok",
63 	[PPC_ADMA_INIT_MEMRES] = "failed to get memory resource",
64 	[PPC_ADMA_INIT_MEMREG] = "failed to request memory region",
65 	[PPC_ADMA_INIT_ALLOC] = "failed to allocate memory for adev "
66 				"structure",
67 	[PPC_ADMA_INIT_COHERENT] = "failed to allocate coherent memory for "
68 				   "hardware descriptors",
69 	[PPC_ADMA_INIT_CHANNEL] = "failed to allocate memory for channel",
70 	[PPC_ADMA_INIT_IRQ1] = "failed to request first irq",
71 	[PPC_ADMA_INIT_IRQ2] = "failed to request second irq",
72 	[PPC_ADMA_INIT_REGISTER] = "failed to register dma async device",
73 };
74 
75 static enum ppc_adma_init_code
76 ppc440spe_adma_devices[PPC440SPE_ADMA_ENGINES_NUM];
77 
78 struct ppc_dma_chan_ref {
79 	struct dma_chan *chan;
80 	struct list_head node;
81 };
82 
83 /* The list of channels exported by ppc440spe ADMA */
84 struct list_head
85 ppc440spe_adma_chan_list = LIST_HEAD_INIT(ppc440spe_adma_chan_list);
86 
87 /* This flag is set when want to refetch the xor chain in the interrupt
88  * handler
89  */
90 static u32 do_xor_refetch;
91 
92 /* Pointer to DMA0, DMA1 CP/CS FIFO */
93 static void *ppc440spe_dma_fifo_buf;
94 
95 /* Pointers to last submitted to DMA0, DMA1 CDBs */
96 static struct ppc440spe_adma_desc_slot *chan_last_sub[3];
97 static struct ppc440spe_adma_desc_slot *chan_first_cdb[3];
98 
99 /* Pointer to last linked and submitted xor CB */
100 static struct ppc440spe_adma_desc_slot *xor_last_linked;
101 static struct ppc440spe_adma_desc_slot *xor_last_submit;
102 
103 /* This array is used in data-check operations for storing a pattern */
104 static char ppc440spe_qword[16];
105 
106 static atomic_t ppc440spe_adma_err_irq_ref;
107 static dcr_host_t ppc440spe_mq_dcr_host;
108 static unsigned int ppc440spe_mq_dcr_len;
109 
110 /* Since RXOR operations use the common register (MQ0_CF2H) for setting-up
111  * the block size in transactions, then we do not allow to activate more than
112  * only one RXOR transactions simultaneously. So use this var to store
113  * the information about is RXOR currently active (PPC440SPE_RXOR_RUN bit is
114  * set) or not (PPC440SPE_RXOR_RUN is clear).
115  */
116 static unsigned long ppc440spe_rxor_state;
117 
118 /* These are used in enable & check routines
119  */
120 static u32 ppc440spe_r6_enabled;
121 static struct ppc440spe_adma_chan *ppc440spe_r6_tchan;
122 static struct completion ppc440spe_r6_test_comp;
123 
124 static int ppc440spe_adma_dma2rxor_prep_src(
125 		struct ppc440spe_adma_desc_slot *desc,
126 		struct ppc440spe_rxor *cursor, int index,
127 		int src_cnt, u32 addr);
128 static void ppc440spe_adma_dma2rxor_set_src(
129 		struct ppc440spe_adma_desc_slot *desc,
130 		int index, dma_addr_t addr);
131 static void ppc440spe_adma_dma2rxor_set_mult(
132 		struct ppc440spe_adma_desc_slot *desc,
133 		int index, u8 mult);
134 
135 #ifdef ADMA_LL_DEBUG
136 #define ADMA_LL_DBG(x) ({ if (1) x; 0; })
137 #else
138 #define ADMA_LL_DBG(x) ({ if (0) x; 0; })
139 #endif
140 
141 static void print_cb(struct ppc440spe_adma_chan *chan, void *block)
142 {
143 	struct dma_cdb *cdb;
144 	struct xor_cb *cb;
145 	int i;
146 
147 	switch (chan->device->id) {
148 	case 0:
149 	case 1:
150 		cdb = block;
151 
152 		pr_debug("CDB at %p [%d]:\n"
153 			"\t attr 0x%02x opc 0x%02x cnt 0x%08x\n"
154 			"\t sg1u 0x%08x sg1l 0x%08x\n"
155 			"\t sg2u 0x%08x sg2l 0x%08x\n"
156 			"\t sg3u 0x%08x sg3l 0x%08x\n",
157 			cdb, chan->device->id,
158 			cdb->attr, cdb->opc, le32_to_cpu(cdb->cnt),
159 			le32_to_cpu(cdb->sg1u), le32_to_cpu(cdb->sg1l),
160 			le32_to_cpu(cdb->sg2u), le32_to_cpu(cdb->sg2l),
161 			le32_to_cpu(cdb->sg3u), le32_to_cpu(cdb->sg3l)
162 		);
163 		break;
164 	case 2:
165 		cb = block;
166 
167 		pr_debug("CB at %p [%d]:\n"
168 			"\t cbc 0x%08x cbbc 0x%08x cbs 0x%08x\n"
169 			"\t cbtah 0x%08x cbtal 0x%08x\n"
170 			"\t cblah 0x%08x cblal 0x%08x\n",
171 			cb, chan->device->id,
172 			cb->cbc, cb->cbbc, cb->cbs,
173 			cb->cbtah, cb->cbtal,
174 			cb->cblah, cb->cblal);
175 		for (i = 0; i < 16; i++) {
176 			if (i && !cb->ops[i].h && !cb->ops[i].l)
177 				continue;
178 			pr_debug("\t ops[%2d]: h 0x%08x l 0x%08x\n",
179 				i, cb->ops[i].h, cb->ops[i].l);
180 		}
181 		break;
182 	}
183 }
184 
185 static void print_cb_list(struct ppc440spe_adma_chan *chan,
186 			  struct ppc440spe_adma_desc_slot *iter)
187 {
188 	for (; iter; iter = iter->hw_next)
189 		print_cb(chan, iter->hw_desc);
190 }
191 
192 static void prep_dma_xor_dbg(int id, dma_addr_t dst, dma_addr_t *src,
193 			     unsigned int src_cnt)
194 {
195 	int i;
196 
197 	pr_debug("\n%s(%d):\nsrc: ", __func__, id);
198 	for (i = 0; i < src_cnt; i++)
199 		pr_debug("\t0x%016llx ", src[i]);
200 	pr_debug("dst:\n\t0x%016llx\n", dst);
201 }
202 
203 static void prep_dma_pq_dbg(int id, dma_addr_t *dst, dma_addr_t *src,
204 			    unsigned int src_cnt)
205 {
206 	int i;
207 
208 	pr_debug("\n%s(%d):\nsrc: ", __func__, id);
209 	for (i = 0; i < src_cnt; i++)
210 		pr_debug("\t0x%016llx ", src[i]);
211 	pr_debug("dst: ");
212 	for (i = 0; i < 2; i++)
213 		pr_debug("\t0x%016llx ", dst[i]);
214 }
215 
216 static void prep_dma_pqzero_sum_dbg(int id, dma_addr_t *src,
217 				    unsigned int src_cnt,
218 				    const unsigned char *scf)
219 {
220 	int i;
221 
222 	pr_debug("\n%s(%d):\nsrc(coef): ", __func__, id);
223 	if (scf) {
224 		for (i = 0; i < src_cnt; i++)
225 			pr_debug("\t0x%016llx(0x%02x) ", src[i], scf[i]);
226 	} else {
227 		for (i = 0; i < src_cnt; i++)
228 			pr_debug("\t0x%016llx(no) ", src[i]);
229 	}
230 
231 	pr_debug("dst: ");
232 	for (i = 0; i < 2; i++)
233 		pr_debug("\t0x%016llx ", src[src_cnt + i]);
234 }
235 
236 /******************************************************************************
237  * Command (Descriptor) Blocks low-level routines
238  ******************************************************************************/
239 /**
240  * ppc440spe_desc_init_interrupt - initialize the descriptor for INTERRUPT
241  * pseudo operation
242  */
243 static void ppc440spe_desc_init_interrupt(struct ppc440spe_adma_desc_slot *desc,
244 					  struct ppc440spe_adma_chan *chan)
245 {
246 	struct xor_cb *p;
247 
248 	switch (chan->device->id) {
249 	case PPC440SPE_XOR_ID:
250 		p = desc->hw_desc;
251 		memset(desc->hw_desc, 0, sizeof(struct xor_cb));
252 		/* NOP with Command Block Complete Enable */
253 		p->cbc = XOR_CBCR_CBCE_BIT;
254 		break;
255 	case PPC440SPE_DMA0_ID:
256 	case PPC440SPE_DMA1_ID:
257 		memset(desc->hw_desc, 0, sizeof(struct dma_cdb));
258 		/* NOP with interrupt */
259 		set_bit(PPC440SPE_DESC_INT, &desc->flags);
260 		break;
261 	default:
262 		printk(KERN_ERR "Unsupported id %d in %s\n", chan->device->id,
263 				__func__);
264 		break;
265 	}
266 }
267 
268 /**
269  * ppc440spe_desc_init_null_xor - initialize the descriptor for NULL XOR
270  * pseudo operation
271  */
272 static void ppc440spe_desc_init_null_xor(struct ppc440spe_adma_desc_slot *desc)
273 {
274 	memset(desc->hw_desc, 0, sizeof(struct xor_cb));
275 	desc->hw_next = NULL;
276 	desc->src_cnt = 0;
277 	desc->dst_cnt = 1;
278 }
279 
280 /**
281  * ppc440spe_desc_init_xor - initialize the descriptor for XOR operation
282  */
283 static void ppc440spe_desc_init_xor(struct ppc440spe_adma_desc_slot *desc,
284 					 int src_cnt, unsigned long flags)
285 {
286 	struct xor_cb *hw_desc = desc->hw_desc;
287 
288 	memset(desc->hw_desc, 0, sizeof(struct xor_cb));
289 	desc->hw_next = NULL;
290 	desc->src_cnt = src_cnt;
291 	desc->dst_cnt = 1;
292 
293 	hw_desc->cbc = XOR_CBCR_TGT_BIT | src_cnt;
294 	if (flags & DMA_PREP_INTERRUPT)
295 		/* Enable interrupt on completion */
296 		hw_desc->cbc |= XOR_CBCR_CBCE_BIT;
297 }
298 
299 /**
300  * ppc440spe_desc_init_dma2pq - initialize the descriptor for PQ
301  * operation in DMA2 controller
302  */
303 static void ppc440spe_desc_init_dma2pq(struct ppc440spe_adma_desc_slot *desc,
304 		int dst_cnt, int src_cnt, unsigned long flags)
305 {
306 	struct xor_cb *hw_desc = desc->hw_desc;
307 
308 	memset(desc->hw_desc, 0, sizeof(struct xor_cb));
309 	desc->hw_next = NULL;
310 	desc->src_cnt = src_cnt;
311 	desc->dst_cnt = dst_cnt;
312 	memset(desc->reverse_flags, 0, sizeof(desc->reverse_flags));
313 	desc->descs_per_op = 0;
314 
315 	hw_desc->cbc = XOR_CBCR_TGT_BIT;
316 	if (flags & DMA_PREP_INTERRUPT)
317 		/* Enable interrupt on completion */
318 		hw_desc->cbc |= XOR_CBCR_CBCE_BIT;
319 }
320 
321 #define DMA_CTRL_FLAGS_LAST	DMA_PREP_FENCE
322 #define DMA_PREP_ZERO_P		(DMA_CTRL_FLAGS_LAST << 1)
323 #define DMA_PREP_ZERO_Q		(DMA_PREP_ZERO_P << 1)
324 
325 /**
326  * ppc440spe_desc_init_dma01pq - initialize the descriptors for PQ operation
327  * with DMA0/1
328  */
329 static void ppc440spe_desc_init_dma01pq(struct ppc440spe_adma_desc_slot *desc,
330 				int dst_cnt, int src_cnt, unsigned long flags,
331 				unsigned long op)
332 {
333 	struct dma_cdb *hw_desc;
334 	struct ppc440spe_adma_desc_slot *iter;
335 	u8 dopc;
336 
337 	/* Common initialization of a PQ descriptors chain */
338 	set_bits(op, &desc->flags);
339 	desc->src_cnt = src_cnt;
340 	desc->dst_cnt = dst_cnt;
341 
342 	/* WXOR MULTICAST if both P and Q are being computed
343 	 * MV_SG1_SG2 if Q only
344 	 */
345 	dopc = (desc->dst_cnt == DMA_DEST_MAX_NUM) ?
346 		DMA_CDB_OPC_MULTICAST : DMA_CDB_OPC_MV_SG1_SG2;
347 
348 	list_for_each_entry(iter, &desc->group_list, chain_node) {
349 		hw_desc = iter->hw_desc;
350 		memset(iter->hw_desc, 0, sizeof(struct dma_cdb));
351 
352 		if (likely(!list_is_last(&iter->chain_node,
353 				&desc->group_list))) {
354 			/* set 'next' pointer */
355 			iter->hw_next = list_entry(iter->chain_node.next,
356 				struct ppc440spe_adma_desc_slot, chain_node);
357 			clear_bit(PPC440SPE_DESC_INT, &iter->flags);
358 		} else {
359 			/* this is the last descriptor.
360 			 * this slot will be pasted from ADMA level
361 			 * each time it wants to configure parameters
362 			 * of the transaction (src, dst, ...)
363 			 */
364 			iter->hw_next = NULL;
365 			if (flags & DMA_PREP_INTERRUPT)
366 				set_bit(PPC440SPE_DESC_INT, &iter->flags);
367 			else
368 				clear_bit(PPC440SPE_DESC_INT, &iter->flags);
369 		}
370 	}
371 
372 	/* Set OPS depending on WXOR/RXOR type of operation */
373 	if (!test_bit(PPC440SPE_DESC_RXOR, &desc->flags)) {
374 		/* This is a WXOR only chain:
375 		 * - first descriptors are for zeroing destinations
376 		 *   if PPC440SPE_ZERO_P/Q set;
377 		 * - descriptors remained are for GF-XOR operations.
378 		 */
379 		iter = list_first_entry(&desc->group_list,
380 					struct ppc440spe_adma_desc_slot,
381 					chain_node);
382 
383 		if (test_bit(PPC440SPE_ZERO_P, &desc->flags)) {
384 			hw_desc = iter->hw_desc;
385 			hw_desc->opc = DMA_CDB_OPC_MV_SG1_SG2;
386 			iter = list_first_entry(&iter->chain_node,
387 					struct ppc440spe_adma_desc_slot,
388 					chain_node);
389 		}
390 
391 		if (test_bit(PPC440SPE_ZERO_Q, &desc->flags)) {
392 			hw_desc = iter->hw_desc;
393 			hw_desc->opc = DMA_CDB_OPC_MV_SG1_SG2;
394 			iter = list_first_entry(&iter->chain_node,
395 					struct ppc440spe_adma_desc_slot,
396 					chain_node);
397 		}
398 
399 		list_for_each_entry_from(iter, &desc->group_list, chain_node) {
400 			hw_desc = iter->hw_desc;
401 			hw_desc->opc = dopc;
402 		}
403 	} else {
404 		/* This is either RXOR-only or mixed RXOR/WXOR */
405 
406 		/* The first 1 or 2 slots in chain are always RXOR,
407 		 * if need to calculate P & Q, then there are two
408 		 * RXOR slots; if only P or only Q, then there is one
409 		 */
410 		iter = list_first_entry(&desc->group_list,
411 					struct ppc440spe_adma_desc_slot,
412 					chain_node);
413 		hw_desc = iter->hw_desc;
414 		hw_desc->opc = DMA_CDB_OPC_MV_SG1_SG2;
415 
416 		if (desc->dst_cnt == DMA_DEST_MAX_NUM) {
417 			iter = list_first_entry(&iter->chain_node,
418 						struct ppc440spe_adma_desc_slot,
419 						chain_node);
420 			hw_desc = iter->hw_desc;
421 			hw_desc->opc = DMA_CDB_OPC_MV_SG1_SG2;
422 		}
423 
424 		/* The remaining descs (if any) are WXORs */
425 		if (test_bit(PPC440SPE_DESC_WXOR, &desc->flags)) {
426 			iter = list_first_entry(&iter->chain_node,
427 						struct ppc440spe_adma_desc_slot,
428 						chain_node);
429 			list_for_each_entry_from(iter, &desc->group_list,
430 						chain_node) {
431 				hw_desc = iter->hw_desc;
432 				hw_desc->opc = dopc;
433 			}
434 		}
435 	}
436 }
437 
438 /**
439  * ppc440spe_desc_init_dma01pqzero_sum - initialize the descriptor
440  * for PQ_ZERO_SUM operation
441  */
442 static void ppc440spe_desc_init_dma01pqzero_sum(
443 				struct ppc440spe_adma_desc_slot *desc,
444 				int dst_cnt, int src_cnt)
445 {
446 	struct dma_cdb *hw_desc;
447 	struct ppc440spe_adma_desc_slot *iter;
448 	int i = 0;
449 	u8 dopc = (dst_cnt == 2) ? DMA_CDB_OPC_MULTICAST :
450 				   DMA_CDB_OPC_MV_SG1_SG2;
451 	/*
452 	 * Initialize starting from 2nd or 3rd descriptor dependent
453 	 * on dst_cnt. First one or two slots are for cloning P
454 	 * and/or Q to chan->pdest and/or chan->qdest as we have
455 	 * to preserve original P/Q.
456 	 */
457 	iter = list_first_entry(&desc->group_list,
458 				struct ppc440spe_adma_desc_slot, chain_node);
459 	iter = list_entry(iter->chain_node.next,
460 			  struct ppc440spe_adma_desc_slot, chain_node);
461 
462 	if (dst_cnt > 1) {
463 		iter = list_entry(iter->chain_node.next,
464 				  struct ppc440spe_adma_desc_slot, chain_node);
465 	}
466 	/* initialize each source descriptor in chain */
467 	list_for_each_entry_from(iter, &desc->group_list, chain_node) {
468 		hw_desc = iter->hw_desc;
469 		memset(iter->hw_desc, 0, sizeof(struct dma_cdb));
470 		iter->src_cnt = 0;
471 		iter->dst_cnt = 0;
472 
473 		/* This is a ZERO_SUM operation:
474 		 * - <src_cnt> descriptors starting from 2nd or 3rd
475 		 *   descriptor are for GF-XOR operations;
476 		 * - remaining <dst_cnt> descriptors are for checking the result
477 		 */
478 		if (i++ < src_cnt)
479 			/* MV_SG1_SG2 if only Q is being verified
480 			 * MULTICAST if both P and Q are being verified
481 			 */
482 			hw_desc->opc = dopc;
483 		else
484 			/* DMA_CDB_OPC_DCHECK128 operation */
485 			hw_desc->opc = DMA_CDB_OPC_DCHECK128;
486 
487 		if (likely(!list_is_last(&iter->chain_node,
488 					 &desc->group_list))) {
489 			/* set 'next' pointer */
490 			iter->hw_next = list_entry(iter->chain_node.next,
491 						struct ppc440spe_adma_desc_slot,
492 						chain_node);
493 		} else {
494 			/* this is the last descriptor.
495 			 * this slot will be pasted from ADMA level
496 			 * each time it wants to configure parameters
497 			 * of the transaction (src, dst, ...)
498 			 */
499 			iter->hw_next = NULL;
500 			/* always enable interrupt generation since we get
501 			 * the status of pqzero from the handler
502 			 */
503 			set_bit(PPC440SPE_DESC_INT, &iter->flags);
504 		}
505 	}
506 	desc->src_cnt = src_cnt;
507 	desc->dst_cnt = dst_cnt;
508 }
509 
510 /**
511  * ppc440spe_desc_init_memcpy - initialize the descriptor for MEMCPY operation
512  */
513 static void ppc440spe_desc_init_memcpy(struct ppc440spe_adma_desc_slot *desc,
514 					unsigned long flags)
515 {
516 	struct dma_cdb *hw_desc = desc->hw_desc;
517 
518 	memset(desc->hw_desc, 0, sizeof(struct dma_cdb));
519 	desc->hw_next = NULL;
520 	desc->src_cnt = 1;
521 	desc->dst_cnt = 1;
522 
523 	if (flags & DMA_PREP_INTERRUPT)
524 		set_bit(PPC440SPE_DESC_INT, &desc->flags);
525 	else
526 		clear_bit(PPC440SPE_DESC_INT, &desc->flags);
527 
528 	hw_desc->opc = DMA_CDB_OPC_MV_SG1_SG2;
529 }
530 
531 /**
532  * ppc440spe_desc_set_src_addr - set source address into the descriptor
533  */
534 static void ppc440spe_desc_set_src_addr(struct ppc440spe_adma_desc_slot *desc,
535 					struct ppc440spe_adma_chan *chan,
536 					int src_idx, dma_addr_t addrh,
537 					dma_addr_t addrl)
538 {
539 	struct dma_cdb *dma_hw_desc;
540 	struct xor_cb *xor_hw_desc;
541 	phys_addr_t addr64, tmplow, tmphi;
542 
543 	switch (chan->device->id) {
544 	case PPC440SPE_DMA0_ID:
545 	case PPC440SPE_DMA1_ID:
546 		if (!addrh) {
547 			addr64 = addrl;
548 			tmphi = (addr64 >> 32);
549 			tmplow = (addr64 & 0xFFFFFFFF);
550 		} else {
551 			tmphi = addrh;
552 			tmplow = addrl;
553 		}
554 		dma_hw_desc = desc->hw_desc;
555 		dma_hw_desc->sg1l = cpu_to_le32((u32)tmplow);
556 		dma_hw_desc->sg1u |= cpu_to_le32((u32)tmphi);
557 		break;
558 	case PPC440SPE_XOR_ID:
559 		xor_hw_desc = desc->hw_desc;
560 		xor_hw_desc->ops[src_idx].l = addrl;
561 		xor_hw_desc->ops[src_idx].h |= addrh;
562 		break;
563 	}
564 }
565 
566 /**
567  * ppc440spe_desc_set_src_mult - set source address mult into the descriptor
568  */
569 static void ppc440spe_desc_set_src_mult(struct ppc440spe_adma_desc_slot *desc,
570 			struct ppc440spe_adma_chan *chan, u32 mult_index,
571 			int sg_index, unsigned char mult_value)
572 {
573 	struct dma_cdb *dma_hw_desc;
574 	struct xor_cb *xor_hw_desc;
575 	u32 *psgu;
576 
577 	switch (chan->device->id) {
578 	case PPC440SPE_DMA0_ID:
579 	case PPC440SPE_DMA1_ID:
580 		dma_hw_desc = desc->hw_desc;
581 
582 		switch (sg_index) {
583 		/* for RXOR operations set multiplier
584 		 * into source cued address
585 		 */
586 		case DMA_CDB_SG_SRC:
587 			psgu = &dma_hw_desc->sg1u;
588 			break;
589 		/* for WXOR operations set multiplier
590 		 * into destination cued address(es)
591 		 */
592 		case DMA_CDB_SG_DST1:
593 			psgu = &dma_hw_desc->sg2u;
594 			break;
595 		case DMA_CDB_SG_DST2:
596 			psgu = &dma_hw_desc->sg3u;
597 			break;
598 		default:
599 			BUG();
600 		}
601 
602 		*psgu |= cpu_to_le32(mult_value << mult_index);
603 		break;
604 	case PPC440SPE_XOR_ID:
605 		xor_hw_desc = desc->hw_desc;
606 		break;
607 	default:
608 		BUG();
609 	}
610 }
611 
612 /**
613  * ppc440spe_desc_set_dest_addr - set destination address into the descriptor
614  */
615 static void ppc440spe_desc_set_dest_addr(struct ppc440spe_adma_desc_slot *desc,
616 				struct ppc440spe_adma_chan *chan,
617 				dma_addr_t addrh, dma_addr_t addrl,
618 				u32 dst_idx)
619 {
620 	struct dma_cdb *dma_hw_desc;
621 	struct xor_cb *xor_hw_desc;
622 	phys_addr_t addr64, tmphi, tmplow;
623 	u32 *psgu, *psgl;
624 
625 	switch (chan->device->id) {
626 	case PPC440SPE_DMA0_ID:
627 	case PPC440SPE_DMA1_ID:
628 		if (!addrh) {
629 			addr64 = addrl;
630 			tmphi = (addr64 >> 32);
631 			tmplow = (addr64 & 0xFFFFFFFF);
632 		} else {
633 			tmphi = addrh;
634 			tmplow = addrl;
635 		}
636 		dma_hw_desc = desc->hw_desc;
637 
638 		psgu = dst_idx ? &dma_hw_desc->sg3u : &dma_hw_desc->sg2u;
639 		psgl = dst_idx ? &dma_hw_desc->sg3l : &dma_hw_desc->sg2l;
640 
641 		*psgl = cpu_to_le32((u32)tmplow);
642 		*psgu |= cpu_to_le32((u32)tmphi);
643 		break;
644 	case PPC440SPE_XOR_ID:
645 		xor_hw_desc = desc->hw_desc;
646 		xor_hw_desc->cbtal = addrl;
647 		xor_hw_desc->cbtah |= addrh;
648 		break;
649 	}
650 }
651 
652 /**
653  * ppc440spe_desc_set_byte_count - set number of data bytes involved
654  * into the operation
655  */
656 static void ppc440spe_desc_set_byte_count(struct ppc440spe_adma_desc_slot *desc,
657 				struct ppc440spe_adma_chan *chan,
658 				u32 byte_count)
659 {
660 	struct dma_cdb *dma_hw_desc;
661 	struct xor_cb *xor_hw_desc;
662 
663 	switch (chan->device->id) {
664 	case PPC440SPE_DMA0_ID:
665 	case PPC440SPE_DMA1_ID:
666 		dma_hw_desc = desc->hw_desc;
667 		dma_hw_desc->cnt = cpu_to_le32(byte_count);
668 		break;
669 	case PPC440SPE_XOR_ID:
670 		xor_hw_desc = desc->hw_desc;
671 		xor_hw_desc->cbbc = byte_count;
672 		break;
673 	}
674 }
675 
676 /**
677  * ppc440spe_desc_set_rxor_block_size - set RXOR block size
678  */
679 static inline void ppc440spe_desc_set_rxor_block_size(u32 byte_count)
680 {
681 	/* assume that byte_count is aligned on the 512-boundary;
682 	 * thus write it directly to the register (bits 23:31 are
683 	 * reserved there).
684 	 */
685 	dcr_write(ppc440spe_mq_dcr_host, DCRN_MQ0_CF2H, byte_count);
686 }
687 
688 /**
689  * ppc440spe_desc_set_dcheck - set CHECK pattern
690  */
691 static void ppc440spe_desc_set_dcheck(struct ppc440spe_adma_desc_slot *desc,
692 				struct ppc440spe_adma_chan *chan, u8 *qword)
693 {
694 	struct dma_cdb *dma_hw_desc;
695 
696 	switch (chan->device->id) {
697 	case PPC440SPE_DMA0_ID:
698 	case PPC440SPE_DMA1_ID:
699 		dma_hw_desc = desc->hw_desc;
700 		iowrite32(qword[0], &dma_hw_desc->sg3l);
701 		iowrite32(qword[4], &dma_hw_desc->sg3u);
702 		iowrite32(qword[8], &dma_hw_desc->sg2l);
703 		iowrite32(qword[12], &dma_hw_desc->sg2u);
704 		break;
705 	default:
706 		BUG();
707 	}
708 }
709 
710 /**
711  * ppc440spe_xor_set_link - set link address in xor CB
712  */
713 static void ppc440spe_xor_set_link(struct ppc440spe_adma_desc_slot *prev_desc,
714 				struct ppc440spe_adma_desc_slot *next_desc)
715 {
716 	struct xor_cb *xor_hw_desc = prev_desc->hw_desc;
717 
718 	if (unlikely(!next_desc || !(next_desc->phys))) {
719 		printk(KERN_ERR "%s: next_desc=0x%p; next_desc->phys=0x%llx\n",
720 			__func__, next_desc,
721 			next_desc ? next_desc->phys : 0);
722 		BUG();
723 	}
724 
725 	xor_hw_desc->cbs = 0;
726 	xor_hw_desc->cblal = next_desc->phys;
727 	xor_hw_desc->cblah = 0;
728 	xor_hw_desc->cbc |= XOR_CBCR_LNK_BIT;
729 }
730 
731 /**
732  * ppc440spe_desc_set_link - set the address of descriptor following this
733  * descriptor in chain
734  */
735 static void ppc440spe_desc_set_link(struct ppc440spe_adma_chan *chan,
736 				struct ppc440spe_adma_desc_slot *prev_desc,
737 				struct ppc440spe_adma_desc_slot *next_desc)
738 {
739 	unsigned long flags;
740 	struct ppc440spe_adma_desc_slot *tail = next_desc;
741 
742 	if (unlikely(!prev_desc || !next_desc ||
743 		(prev_desc->hw_next && prev_desc->hw_next != next_desc))) {
744 		/* If previous next is overwritten something is wrong.
745 		 * though we may refetch from append to initiate list
746 		 * processing; in this case - it's ok.
747 		 */
748 		printk(KERN_ERR "%s: prev_desc=0x%p; next_desc=0x%p; "
749 			"prev->hw_next=0x%p\n", __func__, prev_desc,
750 			next_desc, prev_desc ? prev_desc->hw_next : 0);
751 		BUG();
752 	}
753 
754 	local_irq_save(flags);
755 
756 	/* do s/w chaining both for DMA and XOR descriptors */
757 	prev_desc->hw_next = next_desc;
758 
759 	switch (chan->device->id) {
760 	case PPC440SPE_DMA0_ID:
761 	case PPC440SPE_DMA1_ID:
762 		break;
763 	case PPC440SPE_XOR_ID:
764 		/* bind descriptor to the chain */
765 		while (tail->hw_next)
766 			tail = tail->hw_next;
767 		xor_last_linked = tail;
768 
769 		if (prev_desc == xor_last_submit)
770 			/* do not link to the last submitted CB */
771 			break;
772 		ppc440spe_xor_set_link(prev_desc, next_desc);
773 		break;
774 	}
775 
776 	local_irq_restore(flags);
777 }
778 
779 /**
780  * ppc440spe_desc_get_link - get the address of the descriptor that
781  * follows this one
782  */
783 static inline u32 ppc440spe_desc_get_link(struct ppc440spe_adma_desc_slot *desc,
784 					struct ppc440spe_adma_chan *chan)
785 {
786 	if (!desc->hw_next)
787 		return 0;
788 
789 	return desc->hw_next->phys;
790 }
791 
792 /**
793  * ppc440spe_desc_is_aligned - check alignment
794  */
795 static inline int ppc440spe_desc_is_aligned(
796 	struct ppc440spe_adma_desc_slot *desc, int num_slots)
797 {
798 	return (desc->idx & (num_slots - 1)) ? 0 : 1;
799 }
800 
801 /**
802  * ppc440spe_chan_xor_slot_count - get the number of slots necessary for
803  * XOR operation
804  */
805 static int ppc440spe_chan_xor_slot_count(size_t len, int src_cnt,
806 			int *slots_per_op)
807 {
808 	int slot_cnt;
809 
810 	/* each XOR descriptor provides up to 16 source operands */
811 	slot_cnt = *slots_per_op = (src_cnt + XOR_MAX_OPS - 1)/XOR_MAX_OPS;
812 
813 	if (likely(len <= PPC440SPE_ADMA_XOR_MAX_BYTE_COUNT))
814 		return slot_cnt;
815 
816 	printk(KERN_ERR "%s: len %d > max %d !!\n",
817 		__func__, len, PPC440SPE_ADMA_XOR_MAX_BYTE_COUNT);
818 	BUG();
819 	return slot_cnt;
820 }
821 
822 /**
823  * ppc440spe_dma2_pq_slot_count - get the number of slots necessary for
824  * DMA2 PQ operation
825  */
826 static int ppc440spe_dma2_pq_slot_count(dma_addr_t *srcs,
827 		int src_cnt, size_t len)
828 {
829 	signed long long order = 0;
830 	int state = 0;
831 	int addr_count = 0;
832 	int i;
833 	for (i = 1; i < src_cnt; i++) {
834 		dma_addr_t cur_addr = srcs[i];
835 		dma_addr_t old_addr = srcs[i-1];
836 		switch (state) {
837 		case 0:
838 			if (cur_addr == old_addr + len) {
839 				/* direct RXOR */
840 				order = 1;
841 				state = 1;
842 				if (i == src_cnt-1)
843 					addr_count++;
844 			} else if (old_addr == cur_addr + len) {
845 				/* reverse RXOR */
846 				order = -1;
847 				state = 1;
848 				if (i == src_cnt-1)
849 					addr_count++;
850 			} else {
851 				state = 3;
852 			}
853 			break;
854 		case 1:
855 			if (i == src_cnt-2 || (order == -1
856 				&& cur_addr != old_addr - len)) {
857 				order = 0;
858 				state = 0;
859 				addr_count++;
860 			} else if (cur_addr == old_addr + len*order) {
861 				state = 2;
862 				if (i == src_cnt-1)
863 					addr_count++;
864 			} else if (cur_addr == old_addr + 2*len) {
865 				state = 2;
866 				if (i == src_cnt-1)
867 					addr_count++;
868 			} else if (cur_addr == old_addr + 3*len) {
869 				state = 2;
870 				if (i == src_cnt-1)
871 					addr_count++;
872 			} else {
873 				order = 0;
874 				state = 0;
875 				addr_count++;
876 			}
877 			break;
878 		case 2:
879 			order = 0;
880 			state = 0;
881 			addr_count++;
882 				break;
883 		}
884 		if (state == 3)
885 			break;
886 	}
887 	if (src_cnt <= 1 || (state != 1 && state != 2)) {
888 		pr_err("%s: src_cnt=%d, state=%d, addr_count=%d, order=%lld\n",
889 			__func__, src_cnt, state, addr_count, order);
890 		for (i = 0; i < src_cnt; i++)
891 			pr_err("\t[%d] 0x%llx \n", i, srcs[i]);
892 		BUG();
893 	}
894 
895 	return (addr_count + XOR_MAX_OPS - 1) / XOR_MAX_OPS;
896 }
897 
898 
899 /******************************************************************************
900  * ADMA channel low-level routines
901  ******************************************************************************/
902 
903 static u32
904 ppc440spe_chan_get_current_descriptor(struct ppc440spe_adma_chan *chan);
905 static void ppc440spe_chan_append(struct ppc440spe_adma_chan *chan);
906 
907 /**
908  * ppc440spe_adma_device_clear_eot_status - interrupt ack to XOR or DMA engine
909  */
910 static void ppc440spe_adma_device_clear_eot_status(
911 					struct ppc440spe_adma_chan *chan)
912 {
913 	struct dma_regs *dma_reg;
914 	struct xor_regs *xor_reg;
915 	u8 *p = chan->device->dma_desc_pool_virt;
916 	struct dma_cdb *cdb;
917 	u32 rv, i;
918 
919 	switch (chan->device->id) {
920 	case PPC440SPE_DMA0_ID:
921 	case PPC440SPE_DMA1_ID:
922 		/* read FIFO to ack */
923 		dma_reg = chan->device->dma_reg;
924 		while ((rv = ioread32(&dma_reg->csfpl))) {
925 			i = rv & DMA_CDB_ADDR_MSK;
926 			cdb = (struct dma_cdb *)&p[i -
927 			    (u32)chan->device->dma_desc_pool];
928 
929 			/* Clear opcode to ack. This is necessary for
930 			 * ZeroSum operations only
931 			 */
932 			cdb->opc = 0;
933 
934 			if (test_bit(PPC440SPE_RXOR_RUN,
935 			    &ppc440spe_rxor_state)) {
936 				/* probably this is a completed RXOR op,
937 				 * get pointer to CDB using the fact that
938 				 * physical and virtual addresses of CDB
939 				 * in pools have the same offsets
940 				 */
941 				if (le32_to_cpu(cdb->sg1u) &
942 				    DMA_CUED_XOR_BASE) {
943 					/* this is a RXOR */
944 					clear_bit(PPC440SPE_RXOR_RUN,
945 						  &ppc440spe_rxor_state);
946 				}
947 			}
948 
949 			if (rv & DMA_CDB_STATUS_MSK) {
950 				/* ZeroSum check failed
951 				 */
952 				struct ppc440spe_adma_desc_slot *iter;
953 				dma_addr_t phys = rv & ~DMA_CDB_MSK;
954 
955 				/*
956 				 * Update the status of corresponding
957 				 * descriptor.
958 				 */
959 				list_for_each_entry(iter, &chan->chain,
960 				    chain_node) {
961 					if (iter->phys == phys)
962 						break;
963 				}
964 				/*
965 				 * if cannot find the corresponding
966 				 * slot it's a bug
967 				 */
968 				BUG_ON(&iter->chain_node == &chan->chain);
969 
970 				if (iter->xor_check_result) {
971 					if (test_bit(PPC440SPE_DESC_PCHECK,
972 						     &iter->flags)) {
973 						*iter->xor_check_result |=
974 							SUM_CHECK_P_RESULT;
975 					} else
976 					if (test_bit(PPC440SPE_DESC_QCHECK,
977 						     &iter->flags)) {
978 						*iter->xor_check_result |=
979 							SUM_CHECK_Q_RESULT;
980 					} else
981 						BUG();
982 				}
983 			}
984 		}
985 
986 		rv = ioread32(&dma_reg->dsts);
987 		if (rv) {
988 			pr_err("DMA%d err status: 0x%x\n",
989 			       chan->device->id, rv);
990 			/* write back to clear */
991 			iowrite32(rv, &dma_reg->dsts);
992 		}
993 		break;
994 	case PPC440SPE_XOR_ID:
995 		/* reset status bits to ack */
996 		xor_reg = chan->device->xor_reg;
997 		rv = ioread32be(&xor_reg->sr);
998 		iowrite32be(rv, &xor_reg->sr);
999 
1000 		if (rv & (XOR_IE_ICBIE_BIT|XOR_IE_ICIE_BIT|XOR_IE_RPTIE_BIT)) {
1001 			if (rv & XOR_IE_RPTIE_BIT) {
1002 				/* Read PLB Timeout Error.
1003 				 * Try to resubmit the CB
1004 				 */
1005 				u32 val = ioread32be(&xor_reg->ccbalr);
1006 
1007 				iowrite32be(val, &xor_reg->cblalr);
1008 
1009 				val = ioread32be(&xor_reg->crsr);
1010 				iowrite32be(val | XOR_CRSR_XAE_BIT,
1011 					    &xor_reg->crsr);
1012 			} else
1013 				pr_err("XOR ERR 0x%x status\n", rv);
1014 			break;
1015 		}
1016 
1017 		/*  if the XORcore is idle, but there are unprocessed CBs
1018 		 * then refetch the s/w chain here
1019 		 */
1020 		if (!(ioread32be(&xor_reg->sr) & XOR_SR_XCP_BIT) &&
1021 		    do_xor_refetch)
1022 			ppc440spe_chan_append(chan);
1023 		break;
1024 	}
1025 }
1026 
1027 /**
1028  * ppc440spe_chan_is_busy - get the channel status
1029  */
1030 static int ppc440spe_chan_is_busy(struct ppc440spe_adma_chan *chan)
1031 {
1032 	struct dma_regs *dma_reg;
1033 	struct xor_regs *xor_reg;
1034 	int busy = 0;
1035 
1036 	switch (chan->device->id) {
1037 	case PPC440SPE_DMA0_ID:
1038 	case PPC440SPE_DMA1_ID:
1039 		dma_reg = chan->device->dma_reg;
1040 		/*  if command FIFO's head and tail pointers are equal and
1041 		 * status tail is the same as command, then channel is free
1042 		 */
1043 		if (ioread16(&dma_reg->cpfhp) != ioread16(&dma_reg->cpftp) ||
1044 		    ioread16(&dma_reg->cpftp) != ioread16(&dma_reg->csftp))
1045 			busy = 1;
1046 		break;
1047 	case PPC440SPE_XOR_ID:
1048 		/* use the special status bit for the XORcore
1049 		 */
1050 		xor_reg = chan->device->xor_reg;
1051 		busy = (ioread32be(&xor_reg->sr) & XOR_SR_XCP_BIT) ? 1 : 0;
1052 		break;
1053 	}
1054 
1055 	return busy;
1056 }
1057 
1058 /**
1059  * ppc440spe_chan_set_first_xor_descriptor -  init XORcore chain
1060  */
1061 static void ppc440spe_chan_set_first_xor_descriptor(
1062 				struct ppc440spe_adma_chan *chan,
1063 				struct ppc440spe_adma_desc_slot *next_desc)
1064 {
1065 	struct xor_regs *xor_reg = chan->device->xor_reg;
1066 
1067 	if (ioread32be(&xor_reg->sr) & XOR_SR_XCP_BIT)
1068 		printk(KERN_INFO "%s: Warn: XORcore is running "
1069 			"when try to set the first CDB!\n",
1070 			__func__);
1071 
1072 	xor_last_submit = xor_last_linked = next_desc;
1073 
1074 	iowrite32be(XOR_CRSR_64BA_BIT, &xor_reg->crsr);
1075 
1076 	iowrite32be(next_desc->phys, &xor_reg->cblalr);
1077 	iowrite32be(0, &xor_reg->cblahr);
1078 	iowrite32be(ioread32be(&xor_reg->cbcr) | XOR_CBCR_LNK_BIT,
1079 		    &xor_reg->cbcr);
1080 
1081 	chan->hw_chain_inited = 1;
1082 }
1083 
1084 /**
1085  * ppc440spe_dma_put_desc - put DMA0,1 descriptor to FIFO.
1086  * called with irqs disabled
1087  */
1088 static void ppc440spe_dma_put_desc(struct ppc440spe_adma_chan *chan,
1089 		struct ppc440spe_adma_desc_slot *desc)
1090 {
1091 	u32 pcdb;
1092 	struct dma_regs *dma_reg = chan->device->dma_reg;
1093 
1094 	pcdb = desc->phys;
1095 	if (!test_bit(PPC440SPE_DESC_INT, &desc->flags))
1096 		pcdb |= DMA_CDB_NO_INT;
1097 
1098 	chan_last_sub[chan->device->id] = desc;
1099 
1100 	ADMA_LL_DBG(print_cb(chan, desc->hw_desc));
1101 
1102 	iowrite32(pcdb, &dma_reg->cpfpl);
1103 }
1104 
1105 /**
1106  * ppc440spe_chan_append - update the h/w chain in the channel
1107  */
1108 static void ppc440spe_chan_append(struct ppc440spe_adma_chan *chan)
1109 {
1110 	struct xor_regs *xor_reg;
1111 	struct ppc440spe_adma_desc_slot *iter;
1112 	struct xor_cb *xcb;
1113 	u32 cur_desc;
1114 	unsigned long flags;
1115 
1116 	local_irq_save(flags);
1117 
1118 	switch (chan->device->id) {
1119 	case PPC440SPE_DMA0_ID:
1120 	case PPC440SPE_DMA1_ID:
1121 		cur_desc = ppc440spe_chan_get_current_descriptor(chan);
1122 
1123 		if (likely(cur_desc)) {
1124 			iter = chan_last_sub[chan->device->id];
1125 			BUG_ON(!iter);
1126 		} else {
1127 			/* first peer */
1128 			iter = chan_first_cdb[chan->device->id];
1129 			BUG_ON(!iter);
1130 			ppc440spe_dma_put_desc(chan, iter);
1131 			chan->hw_chain_inited = 1;
1132 		}
1133 
1134 		/* is there something new to append */
1135 		if (!iter->hw_next)
1136 			break;
1137 
1138 		/* flush descriptors from the s/w queue to fifo */
1139 		list_for_each_entry_continue(iter, &chan->chain, chain_node) {
1140 			ppc440spe_dma_put_desc(chan, iter);
1141 			if (!iter->hw_next)
1142 				break;
1143 		}
1144 		break;
1145 	case PPC440SPE_XOR_ID:
1146 		/* update h/w links and refetch */
1147 		if (!xor_last_submit->hw_next)
1148 			break;
1149 
1150 		xor_reg = chan->device->xor_reg;
1151 		/* the last linked CDB has to generate an interrupt
1152 		 * that we'd be able to append the next lists to h/w
1153 		 * regardless of the XOR engine state at the moment of
1154 		 * appending of these next lists
1155 		 */
1156 		xcb = xor_last_linked->hw_desc;
1157 		xcb->cbc |= XOR_CBCR_CBCE_BIT;
1158 
1159 		if (!(ioread32be(&xor_reg->sr) & XOR_SR_XCP_BIT)) {
1160 			/* XORcore is idle. Refetch now */
1161 			do_xor_refetch = 0;
1162 			ppc440spe_xor_set_link(xor_last_submit,
1163 				xor_last_submit->hw_next);
1164 
1165 			ADMA_LL_DBG(print_cb_list(chan,
1166 				xor_last_submit->hw_next));
1167 
1168 			xor_last_submit = xor_last_linked;
1169 			iowrite32be(ioread32be(&xor_reg->crsr) |
1170 				    XOR_CRSR_RCBE_BIT | XOR_CRSR_64BA_BIT,
1171 				    &xor_reg->crsr);
1172 		} else {
1173 			/* XORcore is running. Refetch later in the handler */
1174 			do_xor_refetch = 1;
1175 		}
1176 
1177 		break;
1178 	}
1179 
1180 	local_irq_restore(flags);
1181 }
1182 
1183 /**
1184  * ppc440spe_chan_get_current_descriptor - get the currently executed descriptor
1185  */
1186 static u32
1187 ppc440spe_chan_get_current_descriptor(struct ppc440spe_adma_chan *chan)
1188 {
1189 	struct dma_regs *dma_reg;
1190 	struct xor_regs *xor_reg;
1191 
1192 	if (unlikely(!chan->hw_chain_inited))
1193 		/* h/w descriptor chain is not initialized yet */
1194 		return 0;
1195 
1196 	switch (chan->device->id) {
1197 	case PPC440SPE_DMA0_ID:
1198 	case PPC440SPE_DMA1_ID:
1199 		dma_reg = chan->device->dma_reg;
1200 		return ioread32(&dma_reg->acpl) & (~DMA_CDB_MSK);
1201 	case PPC440SPE_XOR_ID:
1202 		xor_reg = chan->device->xor_reg;
1203 		return ioread32be(&xor_reg->ccbalr);
1204 	}
1205 	return 0;
1206 }
1207 
1208 /**
1209  * ppc440spe_chan_run - enable the channel
1210  */
1211 static void ppc440spe_chan_run(struct ppc440spe_adma_chan *chan)
1212 {
1213 	struct xor_regs *xor_reg;
1214 
1215 	switch (chan->device->id) {
1216 	case PPC440SPE_DMA0_ID:
1217 	case PPC440SPE_DMA1_ID:
1218 		/* DMAs are always enabled, do nothing */
1219 		break;
1220 	case PPC440SPE_XOR_ID:
1221 		/* drain write buffer */
1222 		xor_reg = chan->device->xor_reg;
1223 
1224 		/* fetch descriptor pointed to in <link> */
1225 		iowrite32be(XOR_CRSR_64BA_BIT | XOR_CRSR_XAE_BIT,
1226 			    &xor_reg->crsr);
1227 		break;
1228 	}
1229 }
1230 
1231 /******************************************************************************
1232  * ADMA device level
1233  ******************************************************************************/
1234 
1235 static void ppc440spe_chan_start_null_xor(struct ppc440spe_adma_chan *chan);
1236 static int ppc440spe_adma_alloc_chan_resources(struct dma_chan *chan);
1237 
1238 static dma_cookie_t
1239 ppc440spe_adma_tx_submit(struct dma_async_tx_descriptor *tx);
1240 
1241 static void ppc440spe_adma_set_dest(struct ppc440spe_adma_desc_slot *tx,
1242 				    dma_addr_t addr, int index);
1243 static void
1244 ppc440spe_adma_memcpy_xor_set_src(struct ppc440spe_adma_desc_slot *tx,
1245 				  dma_addr_t addr, int index);
1246 
1247 static void
1248 ppc440spe_adma_pq_set_dest(struct ppc440spe_adma_desc_slot *tx,
1249 			   dma_addr_t *paddr, unsigned long flags);
1250 static void
1251 ppc440spe_adma_pq_set_src(struct ppc440spe_adma_desc_slot *tx,
1252 			  dma_addr_t addr, int index);
1253 static void
1254 ppc440spe_adma_pq_set_src_mult(struct ppc440spe_adma_desc_slot *tx,
1255 			       unsigned char mult, int index, int dst_pos);
1256 static void
1257 ppc440spe_adma_pqzero_sum_set_dest(struct ppc440spe_adma_desc_slot *tx,
1258 				   dma_addr_t paddr, dma_addr_t qaddr);
1259 
1260 static struct page *ppc440spe_rxor_srcs[32];
1261 
1262 /**
1263  * ppc440spe_can_rxor - check if the operands may be processed with RXOR
1264  */
1265 static int ppc440spe_can_rxor(struct page **srcs, int src_cnt, size_t len)
1266 {
1267 	int i, order = 0, state = 0;
1268 	int idx = 0;
1269 
1270 	if (unlikely(!(src_cnt > 1)))
1271 		return 0;
1272 
1273 	BUG_ON(src_cnt > ARRAY_SIZE(ppc440spe_rxor_srcs));
1274 
1275 	/* Skip holes in the source list before checking */
1276 	for (i = 0; i < src_cnt; i++) {
1277 		if (!srcs[i])
1278 			continue;
1279 		ppc440spe_rxor_srcs[idx++] = srcs[i];
1280 	}
1281 	src_cnt = idx;
1282 
1283 	for (i = 1; i < src_cnt; i++) {
1284 		char *cur_addr = page_address(ppc440spe_rxor_srcs[i]);
1285 		char *old_addr = page_address(ppc440spe_rxor_srcs[i - 1]);
1286 
1287 		switch (state) {
1288 		case 0:
1289 			if (cur_addr == old_addr + len) {
1290 				/* direct RXOR */
1291 				order = 1;
1292 				state = 1;
1293 			} else if (old_addr == cur_addr + len) {
1294 				/* reverse RXOR */
1295 				order = -1;
1296 				state = 1;
1297 			} else
1298 				goto out;
1299 			break;
1300 		case 1:
1301 			if ((i == src_cnt - 2) ||
1302 			    (order == -1 && cur_addr != old_addr - len)) {
1303 				order = 0;
1304 				state = 0;
1305 			} else if ((cur_addr == old_addr + len * order) ||
1306 				   (cur_addr == old_addr + 2 * len) ||
1307 				   (cur_addr == old_addr + 3 * len)) {
1308 				state = 2;
1309 			} else {
1310 				order = 0;
1311 				state = 0;
1312 			}
1313 			break;
1314 		case 2:
1315 			order = 0;
1316 			state = 0;
1317 			break;
1318 		}
1319 	}
1320 
1321 out:
1322 	if (state == 1 || state == 2)
1323 		return 1;
1324 
1325 	return 0;
1326 }
1327 
1328 /**
1329  * ppc440spe_adma_device_estimate - estimate the efficiency of processing
1330  *	the operation given on this channel. It's assumed that 'chan' is
1331  *	capable to process 'cap' type of operation.
1332  * @chan: channel to use
1333  * @cap: type of transaction
1334  * @dst_lst: array of destination pointers
1335  * @dst_cnt: number of destination operands
1336  * @src_lst: array of source pointers
1337  * @src_cnt: number of source operands
1338  * @src_sz: size of each source operand
1339  */
1340 static int ppc440spe_adma_estimate(struct dma_chan *chan,
1341 	enum dma_transaction_type cap, struct page **dst_lst, int dst_cnt,
1342 	struct page **src_lst, int src_cnt, size_t src_sz)
1343 {
1344 	int ef = 1;
1345 
1346 	if (cap == DMA_PQ || cap == DMA_PQ_VAL) {
1347 		/* If RAID-6 capabilities were not activated don't try
1348 		 * to use them
1349 		 */
1350 		if (unlikely(!ppc440spe_r6_enabled))
1351 			return -1;
1352 	}
1353 	/*  In the current implementation of ppc440spe ADMA driver it
1354 	 * makes sense to pick out only pq case, because it may be
1355 	 * processed:
1356 	 * (1) either using Biskup method on DMA2;
1357 	 * (2) or on DMA0/1.
1358 	 *  Thus we give a favour to (1) if the sources are suitable;
1359 	 * else let it be processed on one of the DMA0/1 engines.
1360 	 *  In the sum_product case where destination is also the
1361 	 * source process it on DMA0/1 only.
1362 	 */
1363 	if (cap == DMA_PQ && chan->chan_id == PPC440SPE_XOR_ID) {
1364 
1365 		if (dst_cnt == 1 && src_cnt == 2 && dst_lst[0] == src_lst[1])
1366 			ef = 0; /* sum_product case, process on DMA0/1 */
1367 		else if (ppc440spe_can_rxor(src_lst, src_cnt, src_sz))
1368 			ef = 3; /* override (DMA0/1 + idle) */
1369 		else
1370 			ef = 0; /* can't process on DMA2 if !rxor */
1371 	}
1372 
1373 	/* channel idleness increases the priority */
1374 	if (likely(ef) &&
1375 	    !ppc440spe_chan_is_busy(to_ppc440spe_adma_chan(chan)))
1376 		ef++;
1377 
1378 	return ef;
1379 }
1380 
1381 struct dma_chan *
1382 ppc440spe_async_tx_find_best_channel(enum dma_transaction_type cap,
1383 	struct page **dst_lst, int dst_cnt, struct page **src_lst,
1384 	int src_cnt, size_t src_sz)
1385 {
1386 	struct dma_chan *best_chan = NULL;
1387 	struct ppc_dma_chan_ref *ref;
1388 	int best_rank = -1;
1389 
1390 	if (unlikely(!src_sz))
1391 		return NULL;
1392 	if (src_sz > PAGE_SIZE) {
1393 		/*
1394 		 * should a user of the api ever pass > PAGE_SIZE requests
1395 		 * we sort out cases where temporary page-sized buffers
1396 		 * are used.
1397 		 */
1398 		switch (cap) {
1399 		case DMA_PQ:
1400 			if (src_cnt == 1 && dst_lst[1] == src_lst[0])
1401 				return NULL;
1402 			if (src_cnt == 2 && dst_lst[1] == src_lst[1])
1403 				return NULL;
1404 			break;
1405 		case DMA_PQ_VAL:
1406 		case DMA_XOR_VAL:
1407 			return NULL;
1408 		default:
1409 			break;
1410 		}
1411 	}
1412 
1413 	list_for_each_entry(ref, &ppc440spe_adma_chan_list, node) {
1414 		if (dma_has_cap(cap, ref->chan->device->cap_mask)) {
1415 			int rank;
1416 
1417 			rank = ppc440spe_adma_estimate(ref->chan, cap, dst_lst,
1418 					dst_cnt, src_lst, src_cnt, src_sz);
1419 			if (rank > best_rank) {
1420 				best_rank = rank;
1421 				best_chan = ref->chan;
1422 			}
1423 		}
1424 	}
1425 
1426 	return best_chan;
1427 }
1428 EXPORT_SYMBOL_GPL(ppc440spe_async_tx_find_best_channel);
1429 
1430 /**
1431  * ppc440spe_get_group_entry - get group entry with index idx
1432  * @tdesc: is the last allocated slot in the group.
1433  */
1434 static struct ppc440spe_adma_desc_slot *
1435 ppc440spe_get_group_entry(struct ppc440spe_adma_desc_slot *tdesc, u32 entry_idx)
1436 {
1437 	struct ppc440spe_adma_desc_slot *iter = tdesc->group_head;
1438 	int i = 0;
1439 
1440 	if (entry_idx < 0 || entry_idx >= (tdesc->src_cnt + tdesc->dst_cnt)) {
1441 		printk("%s: entry_idx %d, src_cnt %d, dst_cnt %d\n",
1442 			__func__, entry_idx, tdesc->src_cnt, tdesc->dst_cnt);
1443 		BUG();
1444 	}
1445 
1446 	list_for_each_entry(iter, &tdesc->group_list, chain_node) {
1447 		if (i++ == entry_idx)
1448 			break;
1449 	}
1450 	return iter;
1451 }
1452 
1453 /**
1454  * ppc440spe_adma_free_slots - flags descriptor slots for reuse
1455  * @slot: Slot to free
1456  * Caller must hold &ppc440spe_chan->lock while calling this function
1457  */
1458 static void ppc440spe_adma_free_slots(struct ppc440spe_adma_desc_slot *slot,
1459 				      struct ppc440spe_adma_chan *chan)
1460 {
1461 	int stride = slot->slots_per_op;
1462 
1463 	while (stride--) {
1464 		slot->slots_per_op = 0;
1465 		slot = list_entry(slot->slot_node.next,
1466 				struct ppc440spe_adma_desc_slot,
1467 				slot_node);
1468 	}
1469 }
1470 
1471 /**
1472  * ppc440spe_adma_run_tx_complete_actions - call functions to be called
1473  * upon completion
1474  */
1475 static dma_cookie_t ppc440spe_adma_run_tx_complete_actions(
1476 		struct ppc440spe_adma_desc_slot *desc,
1477 		struct ppc440spe_adma_chan *chan,
1478 		dma_cookie_t cookie)
1479 {
1480 	BUG_ON(desc->async_tx.cookie < 0);
1481 	if (desc->async_tx.cookie > 0) {
1482 		cookie = desc->async_tx.cookie;
1483 		desc->async_tx.cookie = 0;
1484 
1485 		dma_descriptor_unmap(&desc->async_tx);
1486 		/* call the callback (must not sleep or submit new
1487 		 * operations to this channel)
1488 		 */
1489 		dmaengine_desc_get_callback_invoke(&desc->async_tx, NULL);
1490 	}
1491 
1492 	/* run dependent operations */
1493 	dma_run_dependencies(&desc->async_tx);
1494 
1495 	return cookie;
1496 }
1497 
1498 /**
1499  * ppc440spe_adma_clean_slot - clean up CDB slot (if ack is set)
1500  */
1501 static int ppc440spe_adma_clean_slot(struct ppc440spe_adma_desc_slot *desc,
1502 		struct ppc440spe_adma_chan *chan)
1503 {
1504 	/* the client is allowed to attach dependent operations
1505 	 * until 'ack' is set
1506 	 */
1507 	if (!async_tx_test_ack(&desc->async_tx))
1508 		return 0;
1509 
1510 	/* leave the last descriptor in the chain
1511 	 * so we can append to it
1512 	 */
1513 	if (list_is_last(&desc->chain_node, &chan->chain) ||
1514 	    desc->phys == ppc440spe_chan_get_current_descriptor(chan))
1515 		return 1;
1516 
1517 	if (chan->device->id != PPC440SPE_XOR_ID) {
1518 		/* our DMA interrupt handler clears opc field of
1519 		 * each processed descriptor. For all types of
1520 		 * operations except for ZeroSum we do not actually
1521 		 * need ack from the interrupt handler. ZeroSum is a
1522 		 * special case since the result of this operation
1523 		 * is available from the handler only, so if we see
1524 		 * such type of descriptor (which is unprocessed yet)
1525 		 * then leave it in chain.
1526 		 */
1527 		struct dma_cdb *cdb = desc->hw_desc;
1528 		if (cdb->opc == DMA_CDB_OPC_DCHECK128)
1529 			return 1;
1530 	}
1531 
1532 	dev_dbg(chan->device->common.dev, "\tfree slot %llx: %d stride: %d\n",
1533 		desc->phys, desc->idx, desc->slots_per_op);
1534 
1535 	list_del(&desc->chain_node);
1536 	ppc440spe_adma_free_slots(desc, chan);
1537 	return 0;
1538 }
1539 
1540 /**
1541  * __ppc440spe_adma_slot_cleanup - this is the common clean-up routine
1542  *	which runs through the channel CDBs list until reach the descriptor
1543  *	currently processed. When routine determines that all CDBs of group
1544  *	are completed then corresponding callbacks (if any) are called and slots
1545  *	are freed.
1546  */
1547 static void __ppc440spe_adma_slot_cleanup(struct ppc440spe_adma_chan *chan)
1548 {
1549 	struct ppc440spe_adma_desc_slot *iter, *_iter, *group_start = NULL;
1550 	dma_cookie_t cookie = 0;
1551 	u32 current_desc = ppc440spe_chan_get_current_descriptor(chan);
1552 	int busy = ppc440spe_chan_is_busy(chan);
1553 	int seen_current = 0, slot_cnt = 0, slots_per_op = 0;
1554 
1555 	dev_dbg(chan->device->common.dev, "ppc440spe adma%d: %s\n",
1556 		chan->device->id, __func__);
1557 
1558 	if (!current_desc) {
1559 		/*  There were no transactions yet, so
1560 		 * nothing to clean
1561 		 */
1562 		return;
1563 	}
1564 
1565 	/* free completed slots from the chain starting with
1566 	 * the oldest descriptor
1567 	 */
1568 	list_for_each_entry_safe(iter, _iter, &chan->chain,
1569 					chain_node) {
1570 		dev_dbg(chan->device->common.dev, "\tcookie: %d slot: %d "
1571 		    "busy: %d this_desc: %#llx next_desc: %#x "
1572 		    "cur: %#x ack: %d\n",
1573 		    iter->async_tx.cookie, iter->idx, busy, iter->phys,
1574 		    ppc440spe_desc_get_link(iter, chan), current_desc,
1575 		    async_tx_test_ack(&iter->async_tx));
1576 		prefetch(_iter);
1577 		prefetch(&_iter->async_tx);
1578 
1579 		/* do not advance past the current descriptor loaded into the
1580 		 * hardware channel,subsequent descriptors are either in process
1581 		 * or have not been submitted
1582 		 */
1583 		if (seen_current)
1584 			break;
1585 
1586 		/* stop the search if we reach the current descriptor and the
1587 		 * channel is busy, or if it appears that the current descriptor
1588 		 * needs to be re-read (i.e. has been appended to)
1589 		 */
1590 		if (iter->phys == current_desc) {
1591 			BUG_ON(seen_current++);
1592 			if (busy || ppc440spe_desc_get_link(iter, chan)) {
1593 				/* not all descriptors of the group have
1594 				 * been completed; exit.
1595 				 */
1596 				break;
1597 			}
1598 		}
1599 
1600 		/* detect the start of a group transaction */
1601 		if (!slot_cnt && !slots_per_op) {
1602 			slot_cnt = iter->slot_cnt;
1603 			slots_per_op = iter->slots_per_op;
1604 			if (slot_cnt <= slots_per_op) {
1605 				slot_cnt = 0;
1606 				slots_per_op = 0;
1607 			}
1608 		}
1609 
1610 		if (slot_cnt) {
1611 			if (!group_start)
1612 				group_start = iter;
1613 			slot_cnt -= slots_per_op;
1614 		}
1615 
1616 		/* all the members of a group are complete */
1617 		if (slots_per_op != 0 && slot_cnt == 0) {
1618 			struct ppc440spe_adma_desc_slot *grp_iter, *_grp_iter;
1619 			int end_of_chain = 0;
1620 
1621 			/* clean up the group */
1622 			slot_cnt = group_start->slot_cnt;
1623 			grp_iter = group_start;
1624 			list_for_each_entry_safe_from(grp_iter, _grp_iter,
1625 				&chan->chain, chain_node) {
1626 
1627 				cookie = ppc440spe_adma_run_tx_complete_actions(
1628 					grp_iter, chan, cookie);
1629 
1630 				slot_cnt -= slots_per_op;
1631 				end_of_chain = ppc440spe_adma_clean_slot(
1632 				    grp_iter, chan);
1633 				if (end_of_chain && slot_cnt) {
1634 					/* Should wait for ZeroSum completion */
1635 					if (cookie > 0)
1636 						chan->common.completed_cookie = cookie;
1637 					return;
1638 				}
1639 
1640 				if (slot_cnt == 0 || end_of_chain)
1641 					break;
1642 			}
1643 
1644 			/* the group should be complete at this point */
1645 			BUG_ON(slot_cnt);
1646 
1647 			slots_per_op = 0;
1648 			group_start = NULL;
1649 			if (end_of_chain)
1650 				break;
1651 			else
1652 				continue;
1653 		} else if (slots_per_op) /* wait for group completion */
1654 			continue;
1655 
1656 		cookie = ppc440spe_adma_run_tx_complete_actions(iter, chan,
1657 		    cookie);
1658 
1659 		if (ppc440spe_adma_clean_slot(iter, chan))
1660 			break;
1661 	}
1662 
1663 	BUG_ON(!seen_current);
1664 
1665 	if (cookie > 0) {
1666 		chan->common.completed_cookie = cookie;
1667 		pr_debug("\tcompleted cookie %d\n", cookie);
1668 	}
1669 
1670 }
1671 
1672 /**
1673  * ppc440spe_adma_tasklet - clean up watch-dog initiator
1674  */
1675 static void ppc440spe_adma_tasklet(unsigned long data)
1676 {
1677 	struct ppc440spe_adma_chan *chan = (struct ppc440spe_adma_chan *) data;
1678 
1679 	spin_lock_nested(&chan->lock, SINGLE_DEPTH_NESTING);
1680 	__ppc440spe_adma_slot_cleanup(chan);
1681 	spin_unlock(&chan->lock);
1682 }
1683 
1684 /**
1685  * ppc440spe_adma_slot_cleanup - clean up scheduled initiator
1686  */
1687 static void ppc440spe_adma_slot_cleanup(struct ppc440spe_adma_chan *chan)
1688 {
1689 	spin_lock_bh(&chan->lock);
1690 	__ppc440spe_adma_slot_cleanup(chan);
1691 	spin_unlock_bh(&chan->lock);
1692 }
1693 
1694 /**
1695  * ppc440spe_adma_alloc_slots - allocate free slots (if any)
1696  */
1697 static struct ppc440spe_adma_desc_slot *ppc440spe_adma_alloc_slots(
1698 		struct ppc440spe_adma_chan *chan, int num_slots,
1699 		int slots_per_op)
1700 {
1701 	struct ppc440spe_adma_desc_slot *iter = NULL, *_iter;
1702 	struct ppc440spe_adma_desc_slot *alloc_start = NULL;
1703 	struct list_head chain = LIST_HEAD_INIT(chain);
1704 	int slots_found, retry = 0;
1705 
1706 
1707 	BUG_ON(!num_slots || !slots_per_op);
1708 	/* start search from the last allocated descrtiptor
1709 	 * if a contiguous allocation can not be found start searching
1710 	 * from the beginning of the list
1711 	 */
1712 retry:
1713 	slots_found = 0;
1714 	if (retry == 0)
1715 		iter = chan->last_used;
1716 	else
1717 		iter = list_entry(&chan->all_slots,
1718 				  struct ppc440spe_adma_desc_slot,
1719 				  slot_node);
1720 	list_for_each_entry_safe_continue(iter, _iter, &chan->all_slots,
1721 	    slot_node) {
1722 		prefetch(_iter);
1723 		prefetch(&_iter->async_tx);
1724 		if (iter->slots_per_op) {
1725 			slots_found = 0;
1726 			continue;
1727 		}
1728 
1729 		/* start the allocation if the slot is correctly aligned */
1730 		if (!slots_found++)
1731 			alloc_start = iter;
1732 
1733 		if (slots_found == num_slots) {
1734 			struct ppc440spe_adma_desc_slot *alloc_tail = NULL;
1735 			struct ppc440spe_adma_desc_slot *last_used = NULL;
1736 
1737 			iter = alloc_start;
1738 			while (num_slots) {
1739 				int i;
1740 				/* pre-ack all but the last descriptor */
1741 				if (num_slots != slots_per_op)
1742 					async_tx_ack(&iter->async_tx);
1743 
1744 				list_add_tail(&iter->chain_node, &chain);
1745 				alloc_tail = iter;
1746 				iter->async_tx.cookie = 0;
1747 				iter->hw_next = NULL;
1748 				iter->flags = 0;
1749 				iter->slot_cnt = num_slots;
1750 				iter->xor_check_result = NULL;
1751 				for (i = 0; i < slots_per_op; i++) {
1752 					iter->slots_per_op = slots_per_op - i;
1753 					last_used = iter;
1754 					iter = list_entry(iter->slot_node.next,
1755 						struct ppc440spe_adma_desc_slot,
1756 						slot_node);
1757 				}
1758 				num_slots -= slots_per_op;
1759 			}
1760 			alloc_tail->group_head = alloc_start;
1761 			alloc_tail->async_tx.cookie = -EBUSY;
1762 			list_splice(&chain, &alloc_tail->group_list);
1763 			chan->last_used = last_used;
1764 			return alloc_tail;
1765 		}
1766 	}
1767 	if (!retry++)
1768 		goto retry;
1769 
1770 	/* try to free some slots if the allocation fails */
1771 	tasklet_schedule(&chan->irq_tasklet);
1772 	return NULL;
1773 }
1774 
1775 /**
1776  * ppc440spe_adma_alloc_chan_resources -  allocate pools for CDB slots
1777  */
1778 static int ppc440spe_adma_alloc_chan_resources(struct dma_chan *chan)
1779 {
1780 	struct ppc440spe_adma_chan *ppc440spe_chan;
1781 	struct ppc440spe_adma_desc_slot *slot = NULL;
1782 	char *hw_desc;
1783 	int i, db_sz;
1784 	int init;
1785 
1786 	ppc440spe_chan = to_ppc440spe_adma_chan(chan);
1787 	init = ppc440spe_chan->slots_allocated ? 0 : 1;
1788 	chan->chan_id = ppc440spe_chan->device->id;
1789 
1790 	/* Allocate descriptor slots */
1791 	i = ppc440spe_chan->slots_allocated;
1792 	if (ppc440spe_chan->device->id != PPC440SPE_XOR_ID)
1793 		db_sz = sizeof(struct dma_cdb);
1794 	else
1795 		db_sz = sizeof(struct xor_cb);
1796 
1797 	for (; i < (ppc440spe_chan->device->pool_size / db_sz); i++) {
1798 		slot = kzalloc(sizeof(struct ppc440spe_adma_desc_slot),
1799 			       GFP_KERNEL);
1800 		if (!slot) {
1801 			printk(KERN_INFO "SPE ADMA Channel only initialized"
1802 				" %d descriptor slots", i--);
1803 			break;
1804 		}
1805 
1806 		hw_desc = (char *) ppc440spe_chan->device->dma_desc_pool_virt;
1807 		slot->hw_desc = (void *) &hw_desc[i * db_sz];
1808 		dma_async_tx_descriptor_init(&slot->async_tx, chan);
1809 		slot->async_tx.tx_submit = ppc440spe_adma_tx_submit;
1810 		INIT_LIST_HEAD(&slot->chain_node);
1811 		INIT_LIST_HEAD(&slot->slot_node);
1812 		INIT_LIST_HEAD(&slot->group_list);
1813 		slot->phys = ppc440spe_chan->device->dma_desc_pool + i * db_sz;
1814 		slot->idx = i;
1815 
1816 		spin_lock_bh(&ppc440spe_chan->lock);
1817 		ppc440spe_chan->slots_allocated++;
1818 		list_add_tail(&slot->slot_node, &ppc440spe_chan->all_slots);
1819 		spin_unlock_bh(&ppc440spe_chan->lock);
1820 	}
1821 
1822 	if (i && !ppc440spe_chan->last_used) {
1823 		ppc440spe_chan->last_used =
1824 			list_entry(ppc440spe_chan->all_slots.next,
1825 				struct ppc440spe_adma_desc_slot,
1826 				slot_node);
1827 	}
1828 
1829 	dev_dbg(ppc440spe_chan->device->common.dev,
1830 		"ppc440spe adma%d: allocated %d descriptor slots\n",
1831 		ppc440spe_chan->device->id, i);
1832 
1833 	/* initialize the channel and the chain with a null operation */
1834 	if (init) {
1835 		switch (ppc440spe_chan->device->id) {
1836 		case PPC440SPE_DMA0_ID:
1837 		case PPC440SPE_DMA1_ID:
1838 			ppc440spe_chan->hw_chain_inited = 0;
1839 			/* Use WXOR for self-testing */
1840 			if (!ppc440spe_r6_tchan)
1841 				ppc440spe_r6_tchan = ppc440spe_chan;
1842 			break;
1843 		case PPC440SPE_XOR_ID:
1844 			ppc440spe_chan_start_null_xor(ppc440spe_chan);
1845 			break;
1846 		default:
1847 			BUG();
1848 		}
1849 		ppc440spe_chan->needs_unmap = 1;
1850 	}
1851 
1852 	return (i > 0) ? i : -ENOMEM;
1853 }
1854 
1855 /**
1856  * ppc440spe_rxor_set_region_data -
1857  */
1858 static void ppc440spe_rxor_set_region(struct ppc440spe_adma_desc_slot *desc,
1859 	u8 xor_arg_no, u32 mask)
1860 {
1861 	struct xor_cb *xcb = desc->hw_desc;
1862 
1863 	xcb->ops[xor_arg_no].h |= mask;
1864 }
1865 
1866 /**
1867  * ppc440spe_rxor_set_src -
1868  */
1869 static void ppc440spe_rxor_set_src(struct ppc440spe_adma_desc_slot *desc,
1870 	u8 xor_arg_no, dma_addr_t addr)
1871 {
1872 	struct xor_cb *xcb = desc->hw_desc;
1873 
1874 	xcb->ops[xor_arg_no].h |= DMA_CUED_XOR_BASE;
1875 	xcb->ops[xor_arg_no].l = addr;
1876 }
1877 
1878 /**
1879  * ppc440spe_rxor_set_mult -
1880  */
1881 static void ppc440spe_rxor_set_mult(struct ppc440spe_adma_desc_slot *desc,
1882 	u8 xor_arg_no, u8 idx, u8 mult)
1883 {
1884 	struct xor_cb *xcb = desc->hw_desc;
1885 
1886 	xcb->ops[xor_arg_no].h |= mult << (DMA_CUED_MULT1_OFF + idx * 8);
1887 }
1888 
1889 /**
1890  * ppc440spe_adma_check_threshold - append CDBs to h/w chain if threshold
1891  *	has been achieved
1892  */
1893 static void ppc440spe_adma_check_threshold(struct ppc440spe_adma_chan *chan)
1894 {
1895 	dev_dbg(chan->device->common.dev, "ppc440spe adma%d: pending: %d\n",
1896 		chan->device->id, chan->pending);
1897 
1898 	if (chan->pending >= PPC440SPE_ADMA_THRESHOLD) {
1899 		chan->pending = 0;
1900 		ppc440spe_chan_append(chan);
1901 	}
1902 }
1903 
1904 /**
1905  * ppc440spe_adma_tx_submit - submit new descriptor group to the channel
1906  *	(it's not necessary that descriptors will be submitted to the h/w
1907  *	chains too right now)
1908  */
1909 static dma_cookie_t ppc440spe_adma_tx_submit(struct dma_async_tx_descriptor *tx)
1910 {
1911 	struct ppc440spe_adma_desc_slot *sw_desc;
1912 	struct ppc440spe_adma_chan *chan = to_ppc440spe_adma_chan(tx->chan);
1913 	struct ppc440spe_adma_desc_slot *group_start, *old_chain_tail;
1914 	int slot_cnt;
1915 	int slots_per_op;
1916 	dma_cookie_t cookie;
1917 
1918 	sw_desc = tx_to_ppc440spe_adma_slot(tx);
1919 
1920 	group_start = sw_desc->group_head;
1921 	slot_cnt = group_start->slot_cnt;
1922 	slots_per_op = group_start->slots_per_op;
1923 
1924 	spin_lock_bh(&chan->lock);
1925 	cookie = dma_cookie_assign(tx);
1926 
1927 	if (unlikely(list_empty(&chan->chain))) {
1928 		/* first peer */
1929 		list_splice_init(&sw_desc->group_list, &chan->chain);
1930 		chan_first_cdb[chan->device->id] = group_start;
1931 	} else {
1932 		/* isn't first peer, bind CDBs to chain */
1933 		old_chain_tail = list_entry(chan->chain.prev,
1934 					struct ppc440spe_adma_desc_slot,
1935 					chain_node);
1936 		list_splice_init(&sw_desc->group_list,
1937 		    &old_chain_tail->chain_node);
1938 		/* fix up the hardware chain */
1939 		ppc440spe_desc_set_link(chan, old_chain_tail, group_start);
1940 	}
1941 
1942 	/* increment the pending count by the number of operations */
1943 	chan->pending += slot_cnt / slots_per_op;
1944 	ppc440spe_adma_check_threshold(chan);
1945 	spin_unlock_bh(&chan->lock);
1946 
1947 	dev_dbg(chan->device->common.dev,
1948 		"ppc440spe adma%d: %s cookie: %d slot: %d tx %p\n",
1949 		chan->device->id, __func__,
1950 		sw_desc->async_tx.cookie, sw_desc->idx, sw_desc);
1951 
1952 	return cookie;
1953 }
1954 
1955 /**
1956  * ppc440spe_adma_prep_dma_interrupt - prepare CDB for a pseudo DMA operation
1957  */
1958 static struct dma_async_tx_descriptor *ppc440spe_adma_prep_dma_interrupt(
1959 		struct dma_chan *chan, unsigned long flags)
1960 {
1961 	struct ppc440spe_adma_chan *ppc440spe_chan;
1962 	struct ppc440spe_adma_desc_slot *sw_desc, *group_start;
1963 	int slot_cnt, slots_per_op;
1964 
1965 	ppc440spe_chan = to_ppc440spe_adma_chan(chan);
1966 
1967 	dev_dbg(ppc440spe_chan->device->common.dev,
1968 		"ppc440spe adma%d: %s\n", ppc440spe_chan->device->id,
1969 		__func__);
1970 
1971 	spin_lock_bh(&ppc440spe_chan->lock);
1972 	slot_cnt = slots_per_op = 1;
1973 	sw_desc = ppc440spe_adma_alloc_slots(ppc440spe_chan, slot_cnt,
1974 			slots_per_op);
1975 	if (sw_desc) {
1976 		group_start = sw_desc->group_head;
1977 		ppc440spe_desc_init_interrupt(group_start, ppc440spe_chan);
1978 		group_start->unmap_len = 0;
1979 		sw_desc->async_tx.flags = flags;
1980 	}
1981 	spin_unlock_bh(&ppc440spe_chan->lock);
1982 
1983 	return sw_desc ? &sw_desc->async_tx : NULL;
1984 }
1985 
1986 /**
1987  * ppc440spe_adma_prep_dma_memcpy - prepare CDB for a MEMCPY operation
1988  */
1989 static struct dma_async_tx_descriptor *ppc440spe_adma_prep_dma_memcpy(
1990 		struct dma_chan *chan, dma_addr_t dma_dest,
1991 		dma_addr_t dma_src, size_t len, 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 	if (unlikely(!len))
2000 		return NULL;
2001 
2002 	BUG_ON(len > PPC440SPE_ADMA_DMA_MAX_BYTE_COUNT);
2003 
2004 	spin_lock_bh(&ppc440spe_chan->lock);
2005 
2006 	dev_dbg(ppc440spe_chan->device->common.dev,
2007 		"ppc440spe adma%d: %s len: %u int_en %d\n",
2008 		ppc440spe_chan->device->id, __func__, len,
2009 		flags & DMA_PREP_INTERRUPT ? 1 : 0);
2010 	slot_cnt = slots_per_op = 1;
2011 	sw_desc = ppc440spe_adma_alloc_slots(ppc440spe_chan, slot_cnt,
2012 		slots_per_op);
2013 	if (sw_desc) {
2014 		group_start = sw_desc->group_head;
2015 		ppc440spe_desc_init_memcpy(group_start, flags);
2016 		ppc440spe_adma_set_dest(group_start, dma_dest, 0);
2017 		ppc440spe_adma_memcpy_xor_set_src(group_start, dma_src, 0);
2018 		ppc440spe_desc_set_byte_count(group_start, ppc440spe_chan, len);
2019 		sw_desc->unmap_len = len;
2020 		sw_desc->async_tx.flags = flags;
2021 	}
2022 	spin_unlock_bh(&ppc440spe_chan->lock);
2023 
2024 	return sw_desc ? &sw_desc->async_tx : NULL;
2025 }
2026 
2027 /**
2028  * ppc440spe_adma_prep_dma_xor - prepare CDB for a XOR operation
2029  */
2030 static struct dma_async_tx_descriptor *ppc440spe_adma_prep_dma_xor(
2031 		struct dma_chan *chan, dma_addr_t dma_dest,
2032 		dma_addr_t *dma_src, u32 src_cnt, size_t len,
2033 		unsigned long flags)
2034 {
2035 	struct ppc440spe_adma_chan *ppc440spe_chan;
2036 	struct ppc440spe_adma_desc_slot *sw_desc, *group_start;
2037 	int slot_cnt, slots_per_op;
2038 
2039 	ppc440spe_chan = to_ppc440spe_adma_chan(chan);
2040 
2041 	ADMA_LL_DBG(prep_dma_xor_dbg(ppc440spe_chan->device->id,
2042 				     dma_dest, dma_src, src_cnt));
2043 	if (unlikely(!len))
2044 		return NULL;
2045 	BUG_ON(len > PPC440SPE_ADMA_XOR_MAX_BYTE_COUNT);
2046 
2047 	dev_dbg(ppc440spe_chan->device->common.dev,
2048 		"ppc440spe adma%d: %s src_cnt: %d len: %u int_en: %d\n",
2049 		ppc440spe_chan->device->id, __func__, src_cnt, len,
2050 		flags & DMA_PREP_INTERRUPT ? 1 : 0);
2051 
2052 	spin_lock_bh(&ppc440spe_chan->lock);
2053 	slot_cnt = ppc440spe_chan_xor_slot_count(len, src_cnt, &slots_per_op);
2054 	sw_desc = ppc440spe_adma_alloc_slots(ppc440spe_chan, slot_cnt,
2055 			slots_per_op);
2056 	if (sw_desc) {
2057 		group_start = sw_desc->group_head;
2058 		ppc440spe_desc_init_xor(group_start, src_cnt, flags);
2059 		ppc440spe_adma_set_dest(group_start, dma_dest, 0);
2060 		while (src_cnt--)
2061 			ppc440spe_adma_memcpy_xor_set_src(group_start,
2062 				dma_src[src_cnt], src_cnt);
2063 		ppc440spe_desc_set_byte_count(group_start, ppc440spe_chan, len);
2064 		sw_desc->unmap_len = len;
2065 		sw_desc->async_tx.flags = flags;
2066 	}
2067 	spin_unlock_bh(&ppc440spe_chan->lock);
2068 
2069 	return sw_desc ? &sw_desc->async_tx : NULL;
2070 }
2071 
2072 static inline void
2073 ppc440spe_desc_set_xor_src_cnt(struct ppc440spe_adma_desc_slot *desc,
2074 				int src_cnt);
2075 static void ppc440spe_init_rxor_cursor(struct ppc440spe_rxor *cursor);
2076 
2077 /**
2078  * ppc440spe_adma_init_dma2rxor_slot -
2079  */
2080 static void ppc440spe_adma_init_dma2rxor_slot(
2081 		struct ppc440spe_adma_desc_slot *desc,
2082 		dma_addr_t *src, int src_cnt)
2083 {
2084 	int i;
2085 
2086 	/* initialize CDB */
2087 	for (i = 0; i < src_cnt; i++) {
2088 		ppc440spe_adma_dma2rxor_prep_src(desc, &desc->rxor_cursor, i,
2089 						 desc->src_cnt, (u32)src[i]);
2090 	}
2091 }
2092 
2093 /**
2094  * ppc440spe_dma01_prep_mult -
2095  * for Q operation where destination is also the source
2096  */
2097 static struct ppc440spe_adma_desc_slot *ppc440spe_dma01_prep_mult(
2098 		struct ppc440spe_adma_chan *ppc440spe_chan,
2099 		dma_addr_t *dst, int dst_cnt, dma_addr_t *src, int src_cnt,
2100 		const unsigned char *scf, size_t len, unsigned long flags)
2101 {
2102 	struct ppc440spe_adma_desc_slot *sw_desc = NULL;
2103 	unsigned long op = 0;
2104 	int slot_cnt;
2105 
2106 	set_bit(PPC440SPE_DESC_WXOR, &op);
2107 	slot_cnt = 2;
2108 
2109 	spin_lock_bh(&ppc440spe_chan->lock);
2110 
2111 	/* use WXOR, each descriptor occupies one slot */
2112 	sw_desc = ppc440spe_adma_alloc_slots(ppc440spe_chan, slot_cnt, 1);
2113 	if (sw_desc) {
2114 		struct ppc440spe_adma_chan *chan;
2115 		struct ppc440spe_adma_desc_slot *iter;
2116 		struct dma_cdb *hw_desc;
2117 
2118 		chan = to_ppc440spe_adma_chan(sw_desc->async_tx.chan);
2119 		set_bits(op, &sw_desc->flags);
2120 		sw_desc->src_cnt = src_cnt;
2121 		sw_desc->dst_cnt = dst_cnt;
2122 		/* First descriptor, zero data in the destination and copy it
2123 		 * to q page using MULTICAST transfer.
2124 		 */
2125 		iter = list_first_entry(&sw_desc->group_list,
2126 					struct ppc440spe_adma_desc_slot,
2127 					chain_node);
2128 		memset(iter->hw_desc, 0, sizeof(struct dma_cdb));
2129 		/* set 'next' pointer */
2130 		iter->hw_next = list_entry(iter->chain_node.next,
2131 					   struct ppc440spe_adma_desc_slot,
2132 					   chain_node);
2133 		clear_bit(PPC440SPE_DESC_INT, &iter->flags);
2134 		hw_desc = iter->hw_desc;
2135 		hw_desc->opc = DMA_CDB_OPC_MULTICAST;
2136 
2137 		ppc440spe_desc_set_dest_addr(iter, chan,
2138 					     DMA_CUED_XOR_BASE, dst[0], 0);
2139 		ppc440spe_desc_set_dest_addr(iter, chan, 0, dst[1], 1);
2140 		ppc440spe_desc_set_src_addr(iter, chan, 0, DMA_CUED_XOR_HB,
2141 					    src[0]);
2142 		ppc440spe_desc_set_byte_count(iter, ppc440spe_chan, len);
2143 		iter->unmap_len = len;
2144 
2145 		/*
2146 		 * Second descriptor, multiply data from the q page
2147 		 * and store the result in real destination.
2148 		 */
2149 		iter = list_first_entry(&iter->chain_node,
2150 					struct ppc440spe_adma_desc_slot,
2151 					chain_node);
2152 		memset(iter->hw_desc, 0, sizeof(struct dma_cdb));
2153 		iter->hw_next = NULL;
2154 		if (flags & DMA_PREP_INTERRUPT)
2155 			set_bit(PPC440SPE_DESC_INT, &iter->flags);
2156 		else
2157 			clear_bit(PPC440SPE_DESC_INT, &iter->flags);
2158 
2159 		hw_desc = iter->hw_desc;
2160 		hw_desc->opc = DMA_CDB_OPC_MV_SG1_SG2;
2161 		ppc440spe_desc_set_src_addr(iter, chan, 0,
2162 					    DMA_CUED_XOR_HB, dst[1]);
2163 		ppc440spe_desc_set_dest_addr(iter, chan,
2164 					     DMA_CUED_XOR_BASE, dst[0], 0);
2165 
2166 		ppc440spe_desc_set_src_mult(iter, chan, DMA_CUED_MULT1_OFF,
2167 					    DMA_CDB_SG_DST1, scf[0]);
2168 		ppc440spe_desc_set_byte_count(iter, ppc440spe_chan, len);
2169 		iter->unmap_len = len;
2170 		sw_desc->async_tx.flags = flags;
2171 	}
2172 
2173 	spin_unlock_bh(&ppc440spe_chan->lock);
2174 
2175 	return sw_desc;
2176 }
2177 
2178 /**
2179  * ppc440spe_dma01_prep_sum_product -
2180  * Dx = A*(P+Pxy) + B*(Q+Qxy) operation where destination is also
2181  * the source.
2182  */
2183 static struct ppc440spe_adma_desc_slot *ppc440spe_dma01_prep_sum_product(
2184 		struct ppc440spe_adma_chan *ppc440spe_chan,
2185 		dma_addr_t *dst, dma_addr_t *src, int src_cnt,
2186 		const unsigned char *scf, size_t len, unsigned long flags)
2187 {
2188 	struct ppc440spe_adma_desc_slot *sw_desc = NULL;
2189 	unsigned long op = 0;
2190 	int slot_cnt;
2191 
2192 	set_bit(PPC440SPE_DESC_WXOR, &op);
2193 	slot_cnt = 3;
2194 
2195 	spin_lock_bh(&ppc440spe_chan->lock);
2196 
2197 	/* WXOR, each descriptor occupies one slot */
2198 	sw_desc = ppc440spe_adma_alloc_slots(ppc440spe_chan, slot_cnt, 1);
2199 	if (sw_desc) {
2200 		struct ppc440spe_adma_chan *chan;
2201 		struct ppc440spe_adma_desc_slot *iter;
2202 		struct dma_cdb *hw_desc;
2203 
2204 		chan = to_ppc440spe_adma_chan(sw_desc->async_tx.chan);
2205 		set_bits(op, &sw_desc->flags);
2206 		sw_desc->src_cnt = src_cnt;
2207 		sw_desc->dst_cnt = 1;
2208 		/* 1st descriptor, src[1] data to q page and zero destination */
2209 		iter = list_first_entry(&sw_desc->group_list,
2210 					struct ppc440spe_adma_desc_slot,
2211 					chain_node);
2212 		memset(iter->hw_desc, 0, sizeof(struct dma_cdb));
2213 		iter->hw_next = list_entry(iter->chain_node.next,
2214 					   struct ppc440spe_adma_desc_slot,
2215 					   chain_node);
2216 		clear_bit(PPC440SPE_DESC_INT, &iter->flags);
2217 		hw_desc = iter->hw_desc;
2218 		hw_desc->opc = DMA_CDB_OPC_MULTICAST;
2219 
2220 		ppc440spe_desc_set_dest_addr(iter, chan, DMA_CUED_XOR_BASE,
2221 					     *dst, 0);
2222 		ppc440spe_desc_set_dest_addr(iter, chan, 0,
2223 					     ppc440spe_chan->qdest, 1);
2224 		ppc440spe_desc_set_src_addr(iter, chan, 0, DMA_CUED_XOR_HB,
2225 					    src[1]);
2226 		ppc440spe_desc_set_byte_count(iter, ppc440spe_chan, len);
2227 		iter->unmap_len = len;
2228 
2229 		/* 2nd descriptor, multiply src[1] data and store the
2230 		 * result in destination */
2231 		iter = list_first_entry(&iter->chain_node,
2232 					struct ppc440spe_adma_desc_slot,
2233 					chain_node);
2234 		memset(iter->hw_desc, 0, sizeof(struct dma_cdb));
2235 		/* set 'next' pointer */
2236 		iter->hw_next = list_entry(iter->chain_node.next,
2237 					   struct ppc440spe_adma_desc_slot,
2238 					   chain_node);
2239 		if (flags & DMA_PREP_INTERRUPT)
2240 			set_bit(PPC440SPE_DESC_INT, &iter->flags);
2241 		else
2242 			clear_bit(PPC440SPE_DESC_INT, &iter->flags);
2243 
2244 		hw_desc = iter->hw_desc;
2245 		hw_desc->opc = DMA_CDB_OPC_MV_SG1_SG2;
2246 		ppc440spe_desc_set_src_addr(iter, chan, 0, DMA_CUED_XOR_HB,
2247 					    ppc440spe_chan->qdest);
2248 		ppc440spe_desc_set_dest_addr(iter, chan, DMA_CUED_XOR_BASE,
2249 					     *dst, 0);
2250 		ppc440spe_desc_set_src_mult(iter, chan,	DMA_CUED_MULT1_OFF,
2251 					    DMA_CDB_SG_DST1, scf[1]);
2252 		ppc440spe_desc_set_byte_count(iter, ppc440spe_chan, len);
2253 		iter->unmap_len = len;
2254 
2255 		/*
2256 		 * 3rd descriptor, multiply src[0] data and xor it
2257 		 * with destination
2258 		 */
2259 		iter = list_first_entry(&iter->chain_node,
2260 					struct ppc440spe_adma_desc_slot,
2261 					chain_node);
2262 		memset(iter->hw_desc, 0, sizeof(struct dma_cdb));
2263 		iter->hw_next = NULL;
2264 		if (flags & DMA_PREP_INTERRUPT)
2265 			set_bit(PPC440SPE_DESC_INT, &iter->flags);
2266 		else
2267 			clear_bit(PPC440SPE_DESC_INT, &iter->flags);
2268 
2269 		hw_desc = iter->hw_desc;
2270 		hw_desc->opc = DMA_CDB_OPC_MV_SG1_SG2;
2271 		ppc440spe_desc_set_src_addr(iter, chan, 0, DMA_CUED_XOR_HB,
2272 					    src[0]);
2273 		ppc440spe_desc_set_dest_addr(iter, chan, DMA_CUED_XOR_BASE,
2274 					     *dst, 0);
2275 		ppc440spe_desc_set_src_mult(iter, chan, DMA_CUED_MULT1_OFF,
2276 					    DMA_CDB_SG_DST1, scf[0]);
2277 		ppc440spe_desc_set_byte_count(iter, ppc440spe_chan, len);
2278 		iter->unmap_len = len;
2279 		sw_desc->async_tx.flags = flags;
2280 	}
2281 
2282 	spin_unlock_bh(&ppc440spe_chan->lock);
2283 
2284 	return sw_desc;
2285 }
2286 
2287 static struct ppc440spe_adma_desc_slot *ppc440spe_dma01_prep_pq(
2288 		struct ppc440spe_adma_chan *ppc440spe_chan,
2289 		dma_addr_t *dst, int dst_cnt, dma_addr_t *src, int src_cnt,
2290 		const unsigned char *scf, size_t len, unsigned long flags)
2291 {
2292 	int slot_cnt;
2293 	struct ppc440spe_adma_desc_slot *sw_desc = NULL, *iter;
2294 	unsigned long op = 0;
2295 	unsigned char mult = 1;
2296 
2297 	pr_debug("%s: dst_cnt %d, src_cnt %d, len %d\n",
2298 		 __func__, dst_cnt, src_cnt, len);
2299 	/*  select operations WXOR/RXOR depending on the
2300 	 * source addresses of operators and the number
2301 	 * of destinations (RXOR support only Q-parity calculations)
2302 	 */
2303 	set_bit(PPC440SPE_DESC_WXOR, &op);
2304 	if (!test_and_set_bit(PPC440SPE_RXOR_RUN, &ppc440spe_rxor_state)) {
2305 		/* no active RXOR;
2306 		 * do RXOR if:
2307 		 * - there are more than 1 source,
2308 		 * - len is aligned on 512-byte boundary,
2309 		 * - source addresses fit to one of 4 possible regions.
2310 		 */
2311 		if (src_cnt > 1 &&
2312 		    !(len & MQ0_CF2H_RXOR_BS_MASK) &&
2313 		    (src[0] + len) == src[1]) {
2314 			/* may do RXOR R1 R2 */
2315 			set_bit(PPC440SPE_DESC_RXOR, &op);
2316 			if (src_cnt != 2) {
2317 				/* may try to enhance region of RXOR */
2318 				if ((src[1] + len) == src[2]) {
2319 					/* do RXOR R1 R2 R3 */
2320 					set_bit(PPC440SPE_DESC_RXOR123,
2321 						&op);
2322 				} else if ((src[1] + len * 2) == src[2]) {
2323 					/* do RXOR R1 R2 R4 */
2324 					set_bit(PPC440SPE_DESC_RXOR124, &op);
2325 				} else if ((src[1] + len * 3) == src[2]) {
2326 					/* do RXOR R1 R2 R5 */
2327 					set_bit(PPC440SPE_DESC_RXOR125,
2328 						&op);
2329 				} else {
2330 					/* do RXOR R1 R2 */
2331 					set_bit(PPC440SPE_DESC_RXOR12,
2332 						&op);
2333 				}
2334 			} else {
2335 				/* do RXOR R1 R2 */
2336 				set_bit(PPC440SPE_DESC_RXOR12, &op);
2337 			}
2338 		}
2339 
2340 		if (!test_bit(PPC440SPE_DESC_RXOR, &op)) {
2341 			/* can not do this operation with RXOR */
2342 			clear_bit(PPC440SPE_RXOR_RUN,
2343 				&ppc440spe_rxor_state);
2344 		} else {
2345 			/* can do; set block size right now */
2346 			ppc440spe_desc_set_rxor_block_size(len);
2347 		}
2348 	}
2349 
2350 	/* Number of necessary slots depends on operation type selected */
2351 	if (!test_bit(PPC440SPE_DESC_RXOR, &op)) {
2352 		/*  This is a WXOR only chain. Need descriptors for each
2353 		 * source to GF-XOR them with WXOR, and need descriptors
2354 		 * for each destination to zero them with WXOR
2355 		 */
2356 		slot_cnt = src_cnt;
2357 
2358 		if (flags & DMA_PREP_ZERO_P) {
2359 			slot_cnt++;
2360 			set_bit(PPC440SPE_ZERO_P, &op);
2361 		}
2362 		if (flags & DMA_PREP_ZERO_Q) {
2363 			slot_cnt++;
2364 			set_bit(PPC440SPE_ZERO_Q, &op);
2365 		}
2366 	} else {
2367 		/*  Need 1/2 descriptor for RXOR operation, and
2368 		 * need (src_cnt - (2 or 3)) for WXOR of sources
2369 		 * remained (if any)
2370 		 */
2371 		slot_cnt = dst_cnt;
2372 
2373 		if (flags & DMA_PREP_ZERO_P)
2374 			set_bit(PPC440SPE_ZERO_P, &op);
2375 		if (flags & DMA_PREP_ZERO_Q)
2376 			set_bit(PPC440SPE_ZERO_Q, &op);
2377 
2378 		if (test_bit(PPC440SPE_DESC_RXOR12, &op))
2379 			slot_cnt += src_cnt - 2;
2380 		else
2381 			slot_cnt += src_cnt - 3;
2382 
2383 		/*  Thus we have either RXOR only chain or
2384 		 * mixed RXOR/WXOR
2385 		 */
2386 		if (slot_cnt == dst_cnt)
2387 			/* RXOR only chain */
2388 			clear_bit(PPC440SPE_DESC_WXOR, &op);
2389 	}
2390 
2391 	spin_lock_bh(&ppc440spe_chan->lock);
2392 	/* for both RXOR/WXOR each descriptor occupies one slot */
2393 	sw_desc = ppc440spe_adma_alloc_slots(ppc440spe_chan, slot_cnt, 1);
2394 	if (sw_desc) {
2395 		ppc440spe_desc_init_dma01pq(sw_desc, dst_cnt, src_cnt,
2396 				flags, op);
2397 
2398 		/* setup dst/src/mult */
2399 		pr_debug("%s: set dst descriptor 0, 1: 0x%016llx, 0x%016llx\n",
2400 			 __func__, dst[0], dst[1]);
2401 		ppc440spe_adma_pq_set_dest(sw_desc, dst, flags);
2402 		while (src_cnt--) {
2403 			ppc440spe_adma_pq_set_src(sw_desc, src[src_cnt],
2404 						  src_cnt);
2405 
2406 			/* NOTE: "Multi = 0 is equivalent to = 1" as it
2407 			 * stated in 440SPSPe_RAID6_Addendum_UM_1_17.pdf
2408 			 * doesn't work for RXOR with DMA0/1! Instead, multi=0
2409 			 * leads to zeroing source data after RXOR.
2410 			 * So, for P case set-up mult=1 explicitly.
2411 			 */
2412 			if (!(flags & DMA_PREP_PQ_DISABLE_Q))
2413 				mult = scf[src_cnt];
2414 			ppc440spe_adma_pq_set_src_mult(sw_desc,
2415 				mult, src_cnt,  dst_cnt - 1);
2416 		}
2417 
2418 		/* Setup byte count foreach slot just allocated */
2419 		sw_desc->async_tx.flags = flags;
2420 		list_for_each_entry(iter, &sw_desc->group_list,
2421 				chain_node) {
2422 			ppc440spe_desc_set_byte_count(iter,
2423 				ppc440spe_chan, len);
2424 			iter->unmap_len = len;
2425 		}
2426 	}
2427 	spin_unlock_bh(&ppc440spe_chan->lock);
2428 
2429 	return sw_desc;
2430 }
2431 
2432 static struct ppc440spe_adma_desc_slot *ppc440spe_dma2_prep_pq(
2433 		struct ppc440spe_adma_chan *ppc440spe_chan,
2434 		dma_addr_t *dst, int dst_cnt, dma_addr_t *src, int src_cnt,
2435 		const unsigned char *scf, size_t len, unsigned long flags)
2436 {
2437 	int slot_cnt, descs_per_op;
2438 	struct ppc440spe_adma_desc_slot *sw_desc = NULL, *iter;
2439 	unsigned long op = 0;
2440 	unsigned char mult = 1;
2441 
2442 	BUG_ON(!dst_cnt);
2443 	/*pr_debug("%s: dst_cnt %d, src_cnt %d, len %d\n",
2444 		 __func__, dst_cnt, src_cnt, len);*/
2445 
2446 	spin_lock_bh(&ppc440spe_chan->lock);
2447 	descs_per_op = ppc440spe_dma2_pq_slot_count(src, src_cnt, len);
2448 	if (descs_per_op < 0) {
2449 		spin_unlock_bh(&ppc440spe_chan->lock);
2450 		return NULL;
2451 	}
2452 
2453 	/* depending on number of sources we have 1 or 2 RXOR chains */
2454 	slot_cnt = descs_per_op * dst_cnt;
2455 
2456 	sw_desc = ppc440spe_adma_alloc_slots(ppc440spe_chan, slot_cnt, 1);
2457 	if (sw_desc) {
2458 		op = slot_cnt;
2459 		sw_desc->async_tx.flags = flags;
2460 		list_for_each_entry(iter, &sw_desc->group_list, chain_node) {
2461 			ppc440spe_desc_init_dma2pq(iter, dst_cnt, src_cnt,
2462 				--op ? 0 : flags);
2463 			ppc440spe_desc_set_byte_count(iter, ppc440spe_chan,
2464 				len);
2465 			iter->unmap_len = len;
2466 
2467 			ppc440spe_init_rxor_cursor(&(iter->rxor_cursor));
2468 			iter->rxor_cursor.len = len;
2469 			iter->descs_per_op = descs_per_op;
2470 		}
2471 		op = 0;
2472 		list_for_each_entry(iter, &sw_desc->group_list, chain_node) {
2473 			op++;
2474 			if (op % descs_per_op == 0)
2475 				ppc440spe_adma_init_dma2rxor_slot(iter, src,
2476 								  src_cnt);
2477 			if (likely(!list_is_last(&iter->chain_node,
2478 						 &sw_desc->group_list))) {
2479 				/* set 'next' pointer */
2480 				iter->hw_next =
2481 					list_entry(iter->chain_node.next,
2482 						struct ppc440spe_adma_desc_slot,
2483 						chain_node);
2484 				ppc440spe_xor_set_link(iter, iter->hw_next);
2485 			} else {
2486 				/* this is the last descriptor. */
2487 				iter->hw_next = NULL;
2488 			}
2489 		}
2490 
2491 		/* fixup head descriptor */
2492 		sw_desc->dst_cnt = dst_cnt;
2493 		if (flags & DMA_PREP_ZERO_P)
2494 			set_bit(PPC440SPE_ZERO_P, &sw_desc->flags);
2495 		if (flags & DMA_PREP_ZERO_Q)
2496 			set_bit(PPC440SPE_ZERO_Q, &sw_desc->flags);
2497 
2498 		/* setup dst/src/mult */
2499 		ppc440spe_adma_pq_set_dest(sw_desc, dst, flags);
2500 
2501 		while (src_cnt--) {
2502 			/* handle descriptors (if dst_cnt == 2) inside
2503 			 * the ppc440spe_adma_pq_set_srcxxx() functions
2504 			 */
2505 			ppc440spe_adma_pq_set_src(sw_desc, src[src_cnt],
2506 						  src_cnt);
2507 			if (!(flags & DMA_PREP_PQ_DISABLE_Q))
2508 				mult = scf[src_cnt];
2509 			ppc440spe_adma_pq_set_src_mult(sw_desc,
2510 					mult, src_cnt, dst_cnt - 1);
2511 		}
2512 	}
2513 	spin_unlock_bh(&ppc440spe_chan->lock);
2514 	ppc440spe_desc_set_rxor_block_size(len);
2515 	return sw_desc;
2516 }
2517 
2518 /**
2519  * ppc440spe_adma_prep_dma_pq - prepare CDB (group) for a GF-XOR operation
2520  */
2521 static struct dma_async_tx_descriptor *ppc440spe_adma_prep_dma_pq(
2522 		struct dma_chan *chan, dma_addr_t *dst, dma_addr_t *src,
2523 		unsigned int src_cnt, const unsigned char *scf,
2524 		size_t len, unsigned long flags)
2525 {
2526 	struct ppc440spe_adma_chan *ppc440spe_chan;
2527 	struct ppc440spe_adma_desc_slot *sw_desc = NULL;
2528 	int dst_cnt = 0;
2529 
2530 	ppc440spe_chan = to_ppc440spe_adma_chan(chan);
2531 
2532 	ADMA_LL_DBG(prep_dma_pq_dbg(ppc440spe_chan->device->id,
2533 				    dst, src, src_cnt));
2534 	BUG_ON(!len);
2535 	BUG_ON(len > PPC440SPE_ADMA_XOR_MAX_BYTE_COUNT);
2536 	BUG_ON(!src_cnt);
2537 
2538 	if (src_cnt == 1 && dst[1] == src[0]) {
2539 		dma_addr_t dest[2];
2540 
2541 		/* dst[1] is real destination (Q) */
2542 		dest[0] = dst[1];
2543 		/* this is the page to multicast source data to */
2544 		dest[1] = ppc440spe_chan->qdest;
2545 		sw_desc = ppc440spe_dma01_prep_mult(ppc440spe_chan,
2546 				dest, 2, src, src_cnt, scf, len, flags);
2547 		return sw_desc ? &sw_desc->async_tx : NULL;
2548 	}
2549 
2550 	if (src_cnt == 2 && dst[1] == src[1]) {
2551 		sw_desc = ppc440spe_dma01_prep_sum_product(ppc440spe_chan,
2552 					&dst[1], src, 2, scf, len, flags);
2553 		return sw_desc ? &sw_desc->async_tx : NULL;
2554 	}
2555 
2556 	if (!(flags & DMA_PREP_PQ_DISABLE_P)) {
2557 		BUG_ON(!dst[0]);
2558 		dst_cnt++;
2559 		flags |= DMA_PREP_ZERO_P;
2560 	}
2561 
2562 	if (!(flags & DMA_PREP_PQ_DISABLE_Q)) {
2563 		BUG_ON(!dst[1]);
2564 		dst_cnt++;
2565 		flags |= DMA_PREP_ZERO_Q;
2566 	}
2567 
2568 	BUG_ON(!dst_cnt);
2569 
2570 	dev_dbg(ppc440spe_chan->device->common.dev,
2571 		"ppc440spe adma%d: %s src_cnt: %d len: %u int_en: %d\n",
2572 		ppc440spe_chan->device->id, __func__, src_cnt, len,
2573 		flags & DMA_PREP_INTERRUPT ? 1 : 0);
2574 
2575 	switch (ppc440spe_chan->device->id) {
2576 	case PPC440SPE_DMA0_ID:
2577 	case PPC440SPE_DMA1_ID:
2578 		sw_desc = ppc440spe_dma01_prep_pq(ppc440spe_chan,
2579 				dst, dst_cnt, src, src_cnt, scf,
2580 				len, flags);
2581 		break;
2582 
2583 	case PPC440SPE_XOR_ID:
2584 		sw_desc = ppc440spe_dma2_prep_pq(ppc440spe_chan,
2585 				dst, dst_cnt, src, src_cnt, scf,
2586 				len, flags);
2587 		break;
2588 	}
2589 
2590 	return sw_desc ? &sw_desc->async_tx : NULL;
2591 }
2592 
2593 /**
2594  * ppc440spe_adma_prep_dma_pqzero_sum - prepare CDB group for
2595  * a PQ_ZERO_SUM operation
2596  */
2597 static struct dma_async_tx_descriptor *ppc440spe_adma_prep_dma_pqzero_sum(
2598 		struct dma_chan *chan, dma_addr_t *pq, dma_addr_t *src,
2599 		unsigned int src_cnt, const unsigned char *scf, size_t len,
2600 		enum sum_check_flags *pqres, unsigned long flags)
2601 {
2602 	struct ppc440spe_adma_chan *ppc440spe_chan;
2603 	struct ppc440spe_adma_desc_slot *sw_desc, *iter;
2604 	dma_addr_t pdest, qdest;
2605 	int slot_cnt, slots_per_op, idst, dst_cnt;
2606 
2607 	ppc440spe_chan = to_ppc440spe_adma_chan(chan);
2608 
2609 	if (flags & DMA_PREP_PQ_DISABLE_P)
2610 		pdest = 0;
2611 	else
2612 		pdest = pq[0];
2613 
2614 	if (flags & DMA_PREP_PQ_DISABLE_Q)
2615 		qdest = 0;
2616 	else
2617 		qdest = pq[1];
2618 
2619 	ADMA_LL_DBG(prep_dma_pqzero_sum_dbg(ppc440spe_chan->device->id,
2620 					    src, src_cnt, scf));
2621 
2622 	/* Always use WXOR for P/Q calculations (two destinations).
2623 	 * Need 1 or 2 extra slots to verify results are zero.
2624 	 */
2625 	idst = dst_cnt = (pdest && qdest) ? 2 : 1;
2626 
2627 	/* One additional slot per destination to clone P/Q
2628 	 * before calculation (we have to preserve destinations).
2629 	 */
2630 	slot_cnt = src_cnt + dst_cnt * 2;
2631 	slots_per_op = 1;
2632 
2633 	spin_lock_bh(&ppc440spe_chan->lock);
2634 	sw_desc = ppc440spe_adma_alloc_slots(ppc440spe_chan, slot_cnt,
2635 					     slots_per_op);
2636 	if (sw_desc) {
2637 		ppc440spe_desc_init_dma01pqzero_sum(sw_desc, dst_cnt, src_cnt);
2638 
2639 		/* Setup byte count for each slot just allocated */
2640 		sw_desc->async_tx.flags = flags;
2641 		list_for_each_entry(iter, &sw_desc->group_list, chain_node) {
2642 			ppc440spe_desc_set_byte_count(iter, ppc440spe_chan,
2643 						      len);
2644 			iter->unmap_len = len;
2645 		}
2646 
2647 		if (pdest) {
2648 			struct dma_cdb *hw_desc;
2649 			struct ppc440spe_adma_chan *chan;
2650 
2651 			iter = sw_desc->group_head;
2652 			chan = to_ppc440spe_adma_chan(iter->async_tx.chan);
2653 			memset(iter->hw_desc, 0, sizeof(struct dma_cdb));
2654 			iter->hw_next = list_entry(iter->chain_node.next,
2655 						struct ppc440spe_adma_desc_slot,
2656 						chain_node);
2657 			hw_desc = iter->hw_desc;
2658 			hw_desc->opc = DMA_CDB_OPC_MV_SG1_SG2;
2659 			iter->src_cnt = 0;
2660 			iter->dst_cnt = 0;
2661 			ppc440spe_desc_set_dest_addr(iter, chan, 0,
2662 						     ppc440spe_chan->pdest, 0);
2663 			ppc440spe_desc_set_src_addr(iter, chan, 0, 0, pdest);
2664 			ppc440spe_desc_set_byte_count(iter, ppc440spe_chan,
2665 						      len);
2666 			iter->unmap_len = 0;
2667 			/* override pdest to preserve original P */
2668 			pdest = ppc440spe_chan->pdest;
2669 		}
2670 		if (qdest) {
2671 			struct dma_cdb *hw_desc;
2672 			struct ppc440spe_adma_chan *chan;
2673 
2674 			iter = list_first_entry(&sw_desc->group_list,
2675 						struct ppc440spe_adma_desc_slot,
2676 						chain_node);
2677 			chan = to_ppc440spe_adma_chan(iter->async_tx.chan);
2678 
2679 			if (pdest) {
2680 				iter = list_entry(iter->chain_node.next,
2681 						struct ppc440spe_adma_desc_slot,
2682 						chain_node);
2683 			}
2684 
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->qdest, 0);
2695 			ppc440spe_desc_set_src_addr(iter, chan, 0, 0, qdest);
2696 			ppc440spe_desc_set_byte_count(iter, ppc440spe_chan,
2697 						      len);
2698 			iter->unmap_len = 0;
2699 			/* override qdest to preserve original Q */
2700 			qdest = ppc440spe_chan->qdest;
2701 		}
2702 
2703 		/* Setup destinations for P/Q ops */
2704 		ppc440spe_adma_pqzero_sum_set_dest(sw_desc, pdest, qdest);
2705 
2706 		/* Setup zero QWORDs into DCHECK CDBs */
2707 		idst = dst_cnt;
2708 		list_for_each_entry_reverse(iter, &sw_desc->group_list,
2709 					    chain_node) {
2710 			/*
2711 			 * The last CDB corresponds to Q-parity check,
2712 			 * the one before last CDB corresponds
2713 			 * P-parity check
2714 			 */
2715 			if (idst == DMA_DEST_MAX_NUM) {
2716 				if (idst == dst_cnt) {
2717 					set_bit(PPC440SPE_DESC_QCHECK,
2718 						&iter->flags);
2719 				} else {
2720 					set_bit(PPC440SPE_DESC_PCHECK,
2721 						&iter->flags);
2722 				}
2723 			} else {
2724 				if (qdest) {
2725 					set_bit(PPC440SPE_DESC_QCHECK,
2726 						&iter->flags);
2727 				} else {
2728 					set_bit(PPC440SPE_DESC_PCHECK,
2729 						&iter->flags);
2730 				}
2731 			}
2732 			iter->xor_check_result = pqres;
2733 
2734 			/*
2735 			 * set it to zero, if check fail then result will
2736 			 * be updated
2737 			 */
2738 			*iter->xor_check_result = 0;
2739 			ppc440spe_desc_set_dcheck(iter, ppc440spe_chan,
2740 				ppc440spe_qword);
2741 
2742 			if (!(--dst_cnt))
2743 				break;
2744 		}
2745 
2746 		/* Setup sources and mults for P/Q ops */
2747 		list_for_each_entry_continue_reverse(iter, &sw_desc->group_list,
2748 						     chain_node) {
2749 			struct ppc440spe_adma_chan *chan;
2750 			u32 mult_dst;
2751 
2752 			chan = to_ppc440spe_adma_chan(iter->async_tx.chan);
2753 			ppc440spe_desc_set_src_addr(iter, chan, 0,
2754 						    DMA_CUED_XOR_HB,
2755 						    src[src_cnt - 1]);
2756 			if (qdest) {
2757 				mult_dst = (dst_cnt - 1) ? DMA_CDB_SG_DST2 :
2758 							   DMA_CDB_SG_DST1;
2759 				ppc440spe_desc_set_src_mult(iter, chan,
2760 							    DMA_CUED_MULT1_OFF,
2761 							    mult_dst,
2762 							    scf[src_cnt - 1]);
2763 			}
2764 			if (!(--src_cnt))
2765 				break;
2766 		}
2767 	}
2768 	spin_unlock_bh(&ppc440spe_chan->lock);
2769 	return sw_desc ? &sw_desc->async_tx : NULL;
2770 }
2771 
2772 /**
2773  * ppc440spe_adma_prep_dma_xor_zero_sum - prepare CDB group for
2774  * XOR ZERO_SUM operation
2775  */
2776 static struct dma_async_tx_descriptor *ppc440spe_adma_prep_dma_xor_zero_sum(
2777 		struct dma_chan *chan, dma_addr_t *src, unsigned int src_cnt,
2778 		size_t len, enum sum_check_flags *result, unsigned long flags)
2779 {
2780 	struct dma_async_tx_descriptor *tx;
2781 	dma_addr_t pq[2];
2782 
2783 	/* validate P, disable Q */
2784 	pq[0] = src[0];
2785 	pq[1] = 0;
2786 	flags |= DMA_PREP_PQ_DISABLE_Q;
2787 
2788 	tx = ppc440spe_adma_prep_dma_pqzero_sum(chan, pq, &src[1],
2789 						src_cnt - 1, 0, len,
2790 						result, flags);
2791 	return tx;
2792 }
2793 
2794 /**
2795  * ppc440spe_adma_set_dest - set destination address into descriptor
2796  */
2797 static void ppc440spe_adma_set_dest(struct ppc440spe_adma_desc_slot *sw_desc,
2798 		dma_addr_t addr, int index)
2799 {
2800 	struct ppc440spe_adma_chan *chan;
2801 
2802 	BUG_ON(index >= sw_desc->dst_cnt);
2803 
2804 	chan = to_ppc440spe_adma_chan(sw_desc->async_tx.chan);
2805 
2806 	switch (chan->device->id) {
2807 	case PPC440SPE_DMA0_ID:
2808 	case PPC440SPE_DMA1_ID:
2809 		/* to do: support transfers lengths >
2810 		 * PPC440SPE_ADMA_DMA/XOR_MAX_BYTE_COUNT
2811 		 */
2812 		ppc440spe_desc_set_dest_addr(sw_desc->group_head,
2813 			chan, 0, addr, index);
2814 		break;
2815 	case PPC440SPE_XOR_ID:
2816 		sw_desc = ppc440spe_get_group_entry(sw_desc, index);
2817 		ppc440spe_desc_set_dest_addr(sw_desc,
2818 			chan, 0, addr, index);
2819 		break;
2820 	}
2821 }
2822 
2823 static void ppc440spe_adma_pq_zero_op(struct ppc440spe_adma_desc_slot *iter,
2824 		struct ppc440spe_adma_chan *chan, dma_addr_t addr)
2825 {
2826 	/*  To clear destinations update the descriptor
2827 	 * (P or Q depending on index) as follows:
2828 	 * addr is destination (0 corresponds to SG2):
2829 	 */
2830 	ppc440spe_desc_set_dest_addr(iter, chan, DMA_CUED_XOR_BASE, addr, 0);
2831 
2832 	/* ... and the addr is source: */
2833 	ppc440spe_desc_set_src_addr(iter, chan, 0, DMA_CUED_XOR_HB, addr);
2834 
2835 	/* addr is always SG2 then the mult is always DST1 */
2836 	ppc440spe_desc_set_src_mult(iter, chan, DMA_CUED_MULT1_OFF,
2837 				    DMA_CDB_SG_DST1, 1);
2838 }
2839 
2840 /**
2841  * ppc440spe_adma_pq_set_dest - set destination address into descriptor
2842  * for the PQXOR operation
2843  */
2844 static void ppc440spe_adma_pq_set_dest(struct ppc440spe_adma_desc_slot *sw_desc,
2845 		dma_addr_t *addrs, unsigned long flags)
2846 {
2847 	struct ppc440spe_adma_desc_slot *iter;
2848 	struct ppc440spe_adma_chan *chan;
2849 	dma_addr_t paddr, qaddr;
2850 	dma_addr_t addr = 0, ppath, qpath;
2851 	int index = 0, i;
2852 
2853 	chan = to_ppc440spe_adma_chan(sw_desc->async_tx.chan);
2854 
2855 	if (flags & DMA_PREP_PQ_DISABLE_P)
2856 		paddr = 0;
2857 	else
2858 		paddr = addrs[0];
2859 
2860 	if (flags & DMA_PREP_PQ_DISABLE_Q)
2861 		qaddr = 0;
2862 	else
2863 		qaddr = addrs[1];
2864 
2865 	if (!paddr || !qaddr)
2866 		addr = paddr ? paddr : qaddr;
2867 
2868 	switch (chan->device->id) {
2869 	case PPC440SPE_DMA0_ID:
2870 	case PPC440SPE_DMA1_ID:
2871 		/* walk through the WXOR source list and set P/Q-destinations
2872 		 * for each slot:
2873 		 */
2874 		if (!test_bit(PPC440SPE_DESC_RXOR, &sw_desc->flags)) {
2875 			/* This is WXOR-only chain; may have 1/2 zero descs */
2876 			if (test_bit(PPC440SPE_ZERO_P, &sw_desc->flags))
2877 				index++;
2878 			if (test_bit(PPC440SPE_ZERO_Q, &sw_desc->flags))
2879 				index++;
2880 
2881 			iter = ppc440spe_get_group_entry(sw_desc, index);
2882 			if (addr) {
2883 				/* one destination */
2884 				list_for_each_entry_from(iter,
2885 					&sw_desc->group_list, chain_node)
2886 					ppc440spe_desc_set_dest_addr(iter, chan,
2887 						DMA_CUED_XOR_BASE, addr, 0);
2888 			} else {
2889 				/* two destinations */
2890 				list_for_each_entry_from(iter,
2891 					&sw_desc->group_list, chain_node) {
2892 					ppc440spe_desc_set_dest_addr(iter, chan,
2893 						DMA_CUED_XOR_BASE, paddr, 0);
2894 					ppc440spe_desc_set_dest_addr(iter, chan,
2895 						DMA_CUED_XOR_BASE, qaddr, 1);
2896 				}
2897 			}
2898 
2899 			if (index) {
2900 				/*  To clear destinations update the descriptor
2901 				 * (1st,2nd, or both depending on flags)
2902 				 */
2903 				index = 0;
2904 				if (test_bit(PPC440SPE_ZERO_P,
2905 						&sw_desc->flags)) {
2906 					iter = ppc440spe_get_group_entry(
2907 							sw_desc, index++);
2908 					ppc440spe_adma_pq_zero_op(iter, chan,
2909 							paddr);
2910 				}
2911 
2912 				if (test_bit(PPC440SPE_ZERO_Q,
2913 						&sw_desc->flags)) {
2914 					iter = ppc440spe_get_group_entry(
2915 							sw_desc, index++);
2916 					ppc440spe_adma_pq_zero_op(iter, chan,
2917 							qaddr);
2918 				}
2919 
2920 				return;
2921 			}
2922 		} else {
2923 			/* This is RXOR-only or RXOR/WXOR mixed chain */
2924 
2925 			/* If we want to include destination into calculations,
2926 			 * then make dest addresses cued with mult=1 (XOR).
2927 			 */
2928 			ppath = test_bit(PPC440SPE_ZERO_P, &sw_desc->flags) ?
2929 					DMA_CUED_XOR_HB :
2930 					DMA_CUED_XOR_BASE |
2931 						(1 << DMA_CUED_MULT1_OFF);
2932 			qpath = test_bit(PPC440SPE_ZERO_Q, &sw_desc->flags) ?
2933 					DMA_CUED_XOR_HB :
2934 					DMA_CUED_XOR_BASE |
2935 						(1 << DMA_CUED_MULT1_OFF);
2936 
2937 			/* Setup destination(s) in RXOR slot(s) */
2938 			iter = ppc440spe_get_group_entry(sw_desc, index++);
2939 			ppc440spe_desc_set_dest_addr(iter, chan,
2940 						paddr ? ppath : qpath,
2941 						paddr ? paddr : qaddr, 0);
2942 			if (!addr) {
2943 				/* two destinations */
2944 				iter = ppc440spe_get_group_entry(sw_desc,
2945 								 index++);
2946 				ppc440spe_desc_set_dest_addr(iter, chan,
2947 						qpath, qaddr, 0);
2948 			}
2949 
2950 			if (test_bit(PPC440SPE_DESC_WXOR, &sw_desc->flags)) {
2951 				/* Setup destination(s) in remaining WXOR
2952 				 * slots
2953 				 */
2954 				iter = ppc440spe_get_group_entry(sw_desc,
2955 								 index);
2956 				if (addr) {
2957 					/* one destination */
2958 					list_for_each_entry_from(iter,
2959 					    &sw_desc->group_list,
2960 					    chain_node)
2961 						ppc440spe_desc_set_dest_addr(
2962 							iter, chan,
2963 							DMA_CUED_XOR_BASE,
2964 							addr, 0);
2965 
2966 				} else {
2967 					/* two destinations */
2968 					list_for_each_entry_from(iter,
2969 					    &sw_desc->group_list,
2970 					    chain_node) {
2971 						ppc440spe_desc_set_dest_addr(
2972 							iter, chan,
2973 							DMA_CUED_XOR_BASE,
2974 							paddr, 0);
2975 						ppc440spe_desc_set_dest_addr(
2976 							iter, chan,
2977 							DMA_CUED_XOR_BASE,
2978 							qaddr, 1);
2979 					}
2980 				}
2981 			}
2982 
2983 		}
2984 		break;
2985 
2986 	case PPC440SPE_XOR_ID:
2987 		/* DMA2 descriptors have only 1 destination, so there are
2988 		 * two chains - one for each dest.
2989 		 * If we want to include destination into calculations,
2990 		 * then make dest addresses cued with mult=1 (XOR).
2991 		 */
2992 		ppath = test_bit(PPC440SPE_ZERO_P, &sw_desc->flags) ?
2993 				DMA_CUED_XOR_HB :
2994 				DMA_CUED_XOR_BASE |
2995 					(1 << DMA_CUED_MULT1_OFF);
2996 
2997 		qpath = test_bit(PPC440SPE_ZERO_Q, &sw_desc->flags) ?
2998 				DMA_CUED_XOR_HB :
2999 				DMA_CUED_XOR_BASE |
3000 					(1 << DMA_CUED_MULT1_OFF);
3001 
3002 		iter = ppc440spe_get_group_entry(sw_desc, 0);
3003 		for (i = 0; i < sw_desc->descs_per_op; i++) {
3004 			ppc440spe_desc_set_dest_addr(iter, chan,
3005 				paddr ? ppath : qpath,
3006 				paddr ? paddr : qaddr, 0);
3007 			iter = list_entry(iter->chain_node.next,
3008 					  struct ppc440spe_adma_desc_slot,
3009 					  chain_node);
3010 		}
3011 
3012 		if (!addr) {
3013 			/* Two destinations; setup Q here */
3014 			iter = ppc440spe_get_group_entry(sw_desc,
3015 				sw_desc->descs_per_op);
3016 			for (i = 0; i < sw_desc->descs_per_op; i++) {
3017 				ppc440spe_desc_set_dest_addr(iter,
3018 					chan, qpath, qaddr, 0);
3019 				iter = list_entry(iter->chain_node.next,
3020 						struct ppc440spe_adma_desc_slot,
3021 						chain_node);
3022 			}
3023 		}
3024 
3025 		break;
3026 	}
3027 }
3028 
3029 /**
3030  * ppc440spe_adma_pq_zero_sum_set_dest - set destination address into descriptor
3031  * for the PQ_ZERO_SUM operation
3032  */
3033 static void ppc440spe_adma_pqzero_sum_set_dest(
3034 		struct ppc440spe_adma_desc_slot *sw_desc,
3035 		dma_addr_t paddr, dma_addr_t qaddr)
3036 {
3037 	struct ppc440spe_adma_desc_slot *iter, *end;
3038 	struct ppc440spe_adma_chan *chan;
3039 	dma_addr_t addr = 0;
3040 	int idx;
3041 
3042 	chan = to_ppc440spe_adma_chan(sw_desc->async_tx.chan);
3043 
3044 	/* walk through the WXOR source list and set P/Q-destinations
3045 	 * for each slot
3046 	 */
3047 	idx = (paddr && qaddr) ? 2 : 1;
3048 	/* set end */
3049 	list_for_each_entry_reverse(end, &sw_desc->group_list,
3050 				    chain_node) {
3051 		if (!(--idx))
3052 			break;
3053 	}
3054 	/* set start */
3055 	idx = (paddr && qaddr) ? 2 : 1;
3056 	iter = ppc440spe_get_group_entry(sw_desc, idx);
3057 
3058 	if (paddr && qaddr) {
3059 		/* two destinations */
3060 		list_for_each_entry_from(iter, &sw_desc->group_list,
3061 					 chain_node) {
3062 			if (unlikely(iter == end))
3063 				break;
3064 			ppc440spe_desc_set_dest_addr(iter, chan,
3065 						DMA_CUED_XOR_BASE, paddr, 0);
3066 			ppc440spe_desc_set_dest_addr(iter, chan,
3067 						DMA_CUED_XOR_BASE, qaddr, 1);
3068 		}
3069 	} else {
3070 		/* one destination */
3071 		addr = paddr ? paddr : qaddr;
3072 		list_for_each_entry_from(iter, &sw_desc->group_list,
3073 					 chain_node) {
3074 			if (unlikely(iter == end))
3075 				break;
3076 			ppc440spe_desc_set_dest_addr(iter, chan,
3077 						DMA_CUED_XOR_BASE, addr, 0);
3078 		}
3079 	}
3080 
3081 	/*  The remaining descriptors are DATACHECK. These have no need in
3082 	 * destination. Actually, these destinations are used there
3083 	 * as sources for check operation. So, set addr as source.
3084 	 */
3085 	ppc440spe_desc_set_src_addr(end, chan, 0, 0, addr ? addr : paddr);
3086 
3087 	if (!addr) {
3088 		end = list_entry(end->chain_node.next,
3089 				 struct ppc440spe_adma_desc_slot, chain_node);
3090 		ppc440spe_desc_set_src_addr(end, chan, 0, 0, qaddr);
3091 	}
3092 }
3093 
3094 /**
3095  * ppc440spe_desc_set_xor_src_cnt - set source count into descriptor
3096  */
3097 static inline void ppc440spe_desc_set_xor_src_cnt(
3098 			struct ppc440spe_adma_desc_slot *desc,
3099 			int src_cnt)
3100 {
3101 	struct xor_cb *hw_desc = desc->hw_desc;
3102 
3103 	hw_desc->cbc &= ~XOR_CDCR_OAC_MSK;
3104 	hw_desc->cbc |= src_cnt;
3105 }
3106 
3107 /**
3108  * ppc440spe_adma_pq_set_src - set source address into descriptor
3109  */
3110 static void ppc440spe_adma_pq_set_src(struct ppc440spe_adma_desc_slot *sw_desc,
3111 		dma_addr_t addr, int index)
3112 {
3113 	struct ppc440spe_adma_chan *chan;
3114 	dma_addr_t haddr = 0;
3115 	struct ppc440spe_adma_desc_slot *iter = NULL;
3116 
3117 	chan = to_ppc440spe_adma_chan(sw_desc->async_tx.chan);
3118 
3119 	switch (chan->device->id) {
3120 	case PPC440SPE_DMA0_ID:
3121 	case PPC440SPE_DMA1_ID:
3122 		/* DMA0,1 may do: WXOR, RXOR, RXOR+WXORs chain
3123 		 */
3124 		if (test_bit(PPC440SPE_DESC_RXOR, &sw_desc->flags)) {
3125 			/* RXOR-only or RXOR/WXOR operation */
3126 			int iskip = test_bit(PPC440SPE_DESC_RXOR12,
3127 				&sw_desc->flags) ?  2 : 3;
3128 
3129 			if (index == 0) {
3130 				/* 1st slot (RXOR) */
3131 				/* setup sources region (R1-2-3, R1-2-4,
3132 				 * or R1-2-5)
3133 				 */
3134 				if (test_bit(PPC440SPE_DESC_RXOR12,
3135 						&sw_desc->flags))
3136 					haddr = DMA_RXOR12 <<
3137 						DMA_CUED_REGION_OFF;
3138 				else if (test_bit(PPC440SPE_DESC_RXOR123,
3139 				    &sw_desc->flags))
3140 					haddr = DMA_RXOR123 <<
3141 						DMA_CUED_REGION_OFF;
3142 				else if (test_bit(PPC440SPE_DESC_RXOR124,
3143 				    &sw_desc->flags))
3144 					haddr = DMA_RXOR124 <<
3145 						DMA_CUED_REGION_OFF;
3146 				else if (test_bit(PPC440SPE_DESC_RXOR125,
3147 				    &sw_desc->flags))
3148 					haddr = DMA_RXOR125 <<
3149 						DMA_CUED_REGION_OFF;
3150 				else
3151 					BUG();
3152 				haddr |= DMA_CUED_XOR_BASE;
3153 				iter = ppc440spe_get_group_entry(sw_desc, 0);
3154 			} else if (index < iskip) {
3155 				/* 1st slot (RXOR)
3156 				 * shall actually set source address only once
3157 				 * instead of first <iskip>
3158 				 */
3159 				iter = NULL;
3160 			} else {
3161 				/* 2nd/3d and next slots (WXOR);
3162 				 * skip first slot with RXOR
3163 				 */
3164 				haddr = DMA_CUED_XOR_HB;
3165 				iter = ppc440spe_get_group_entry(sw_desc,
3166 				    index - iskip + sw_desc->dst_cnt);
3167 			}
3168 		} else {
3169 			int znum = 0;
3170 
3171 			/* WXOR-only operation; skip first slots with
3172 			 * zeroing destinations
3173 			 */
3174 			if (test_bit(PPC440SPE_ZERO_P, &sw_desc->flags))
3175 				znum++;
3176 			if (test_bit(PPC440SPE_ZERO_Q, &sw_desc->flags))
3177 				znum++;
3178 
3179 			haddr = DMA_CUED_XOR_HB;
3180 			iter = ppc440spe_get_group_entry(sw_desc,
3181 					index + znum);
3182 		}
3183 
3184 		if (likely(iter)) {
3185 			ppc440spe_desc_set_src_addr(iter, chan, 0, haddr, addr);
3186 
3187 			if (!index &&
3188 			    test_bit(PPC440SPE_DESC_RXOR, &sw_desc->flags) &&
3189 			    sw_desc->dst_cnt == 2) {
3190 				/* if we have two destinations for RXOR, then
3191 				 * setup source in the second descr too
3192 				 */
3193 				iter = ppc440spe_get_group_entry(sw_desc, 1);
3194 				ppc440spe_desc_set_src_addr(iter, chan, 0,
3195 					haddr, addr);
3196 			}
3197 		}
3198 		break;
3199 
3200 	case PPC440SPE_XOR_ID:
3201 		/* DMA2 may do Biskup */
3202 		iter = sw_desc->group_head;
3203 		if (iter->dst_cnt == 2) {
3204 			/* both P & Q calculations required; set P src here */
3205 			ppc440spe_adma_dma2rxor_set_src(iter, index, addr);
3206 
3207 			/* this is for Q */
3208 			iter = ppc440spe_get_group_entry(sw_desc,
3209 				sw_desc->descs_per_op);
3210 		}
3211 		ppc440spe_adma_dma2rxor_set_src(iter, index, addr);
3212 		break;
3213 	}
3214 }
3215 
3216 /**
3217  * ppc440spe_adma_memcpy_xor_set_src - set source address into descriptor
3218  */
3219 static void ppc440spe_adma_memcpy_xor_set_src(
3220 		struct ppc440spe_adma_desc_slot *sw_desc,
3221 		dma_addr_t addr, int index)
3222 {
3223 	struct ppc440spe_adma_chan *chan;
3224 
3225 	chan = to_ppc440spe_adma_chan(sw_desc->async_tx.chan);
3226 	sw_desc = sw_desc->group_head;
3227 
3228 	if (likely(sw_desc))
3229 		ppc440spe_desc_set_src_addr(sw_desc, chan, index, 0, addr);
3230 }
3231 
3232 /**
3233  * ppc440spe_adma_dma2rxor_inc_addr  -
3234  */
3235 static void ppc440spe_adma_dma2rxor_inc_addr(
3236 		struct ppc440spe_adma_desc_slot *desc,
3237 		struct ppc440spe_rxor *cursor, int index, int src_cnt)
3238 {
3239 	cursor->addr_count++;
3240 	if (index == src_cnt - 1) {
3241 		ppc440spe_desc_set_xor_src_cnt(desc, cursor->addr_count);
3242 	} else if (cursor->addr_count == XOR_MAX_OPS) {
3243 		ppc440spe_desc_set_xor_src_cnt(desc, cursor->addr_count);
3244 		cursor->addr_count = 0;
3245 		cursor->desc_count++;
3246 	}
3247 }
3248 
3249 /**
3250  * ppc440spe_adma_dma2rxor_prep_src - setup RXOR types in DMA2 CDB
3251  */
3252 static int ppc440spe_adma_dma2rxor_prep_src(
3253 		struct ppc440spe_adma_desc_slot *hdesc,
3254 		struct ppc440spe_rxor *cursor, int index,
3255 		int src_cnt, u32 addr)
3256 {
3257 	int rval = 0;
3258 	u32 sign;
3259 	struct ppc440spe_adma_desc_slot *desc = hdesc;
3260 	int i;
3261 
3262 	for (i = 0; i < cursor->desc_count; i++) {
3263 		desc = list_entry(hdesc->chain_node.next,
3264 				  struct ppc440spe_adma_desc_slot,
3265 				  chain_node);
3266 	}
3267 
3268 	switch (cursor->state) {
3269 	case 0:
3270 		if (addr == cursor->addrl + cursor->len) {
3271 			/* direct RXOR */
3272 			cursor->state = 1;
3273 			cursor->xor_count++;
3274 			if (index == src_cnt-1) {
3275 				ppc440spe_rxor_set_region(desc,
3276 					cursor->addr_count,
3277 					DMA_RXOR12 << DMA_CUED_REGION_OFF);
3278 				ppc440spe_adma_dma2rxor_inc_addr(
3279 					desc, cursor, index, src_cnt);
3280 			}
3281 		} else if (cursor->addrl == addr + cursor->len) {
3282 			/* reverse RXOR */
3283 			cursor->state = 1;
3284 			cursor->xor_count++;
3285 			set_bit(cursor->addr_count, &desc->reverse_flags[0]);
3286 			if (index == src_cnt-1) {
3287 				ppc440spe_rxor_set_region(desc,
3288 					cursor->addr_count,
3289 					DMA_RXOR12 << DMA_CUED_REGION_OFF);
3290 				ppc440spe_adma_dma2rxor_inc_addr(
3291 					desc, cursor, index, src_cnt);
3292 			}
3293 		} else {
3294 			printk(KERN_ERR "Cannot build "
3295 				"DMA2 RXOR command block.\n");
3296 			BUG();
3297 		}
3298 		break;
3299 	case 1:
3300 		sign = test_bit(cursor->addr_count,
3301 				desc->reverse_flags)
3302 			? -1 : 1;
3303 		if (index == src_cnt-2 || (sign == -1
3304 			&& addr != cursor->addrl - 2*cursor->len)) {
3305 			cursor->state = 0;
3306 			cursor->xor_count = 1;
3307 			cursor->addrl = addr;
3308 			ppc440spe_rxor_set_region(desc,
3309 				cursor->addr_count,
3310 				DMA_RXOR12 << DMA_CUED_REGION_OFF);
3311 			ppc440spe_adma_dma2rxor_inc_addr(
3312 				desc, cursor, index, src_cnt);
3313 		} else if (addr == cursor->addrl + 2*sign*cursor->len) {
3314 			cursor->state = 2;
3315 			cursor->xor_count = 0;
3316 			ppc440spe_rxor_set_region(desc,
3317 				cursor->addr_count,
3318 				DMA_RXOR123 << DMA_CUED_REGION_OFF);
3319 			if (index == src_cnt-1) {
3320 				ppc440spe_adma_dma2rxor_inc_addr(
3321 					desc, cursor, index, src_cnt);
3322 			}
3323 		} else if (addr == cursor->addrl + 3*cursor->len) {
3324 			cursor->state = 2;
3325 			cursor->xor_count = 0;
3326 			ppc440spe_rxor_set_region(desc,
3327 				cursor->addr_count,
3328 				DMA_RXOR124 << DMA_CUED_REGION_OFF);
3329 			if (index == src_cnt-1) {
3330 				ppc440spe_adma_dma2rxor_inc_addr(
3331 					desc, cursor, index, src_cnt);
3332 			}
3333 		} else if (addr == cursor->addrl + 4*cursor->len) {
3334 			cursor->state = 2;
3335 			cursor->xor_count = 0;
3336 			ppc440spe_rxor_set_region(desc,
3337 				cursor->addr_count,
3338 				DMA_RXOR125 << DMA_CUED_REGION_OFF);
3339 			if (index == src_cnt-1) {
3340 				ppc440spe_adma_dma2rxor_inc_addr(
3341 					desc, cursor, index, src_cnt);
3342 			}
3343 		} else {
3344 			cursor->state = 0;
3345 			cursor->xor_count = 1;
3346 			cursor->addrl = addr;
3347 			ppc440spe_rxor_set_region(desc,
3348 				cursor->addr_count,
3349 				DMA_RXOR12 << DMA_CUED_REGION_OFF);
3350 			ppc440spe_adma_dma2rxor_inc_addr(
3351 				desc, cursor, index, src_cnt);
3352 		}
3353 		break;
3354 	case 2:
3355 		cursor->state = 0;
3356 		cursor->addrl = addr;
3357 		cursor->xor_count++;
3358 		if (index) {
3359 			ppc440spe_adma_dma2rxor_inc_addr(
3360 				desc, cursor, index, src_cnt);
3361 		}
3362 		break;
3363 	}
3364 
3365 	return rval;
3366 }
3367 
3368 /**
3369  * ppc440spe_adma_dma2rxor_set_src - set RXOR source address; it's assumed that
3370  *	ppc440spe_adma_dma2rxor_prep_src() has already done prior this call
3371  */
3372 static void ppc440spe_adma_dma2rxor_set_src(
3373 		struct ppc440spe_adma_desc_slot *desc,
3374 		int index, dma_addr_t addr)
3375 {
3376 	struct xor_cb *xcb = desc->hw_desc;
3377 	int k = 0, op = 0, lop = 0;
3378 
3379 	/* get the RXOR operand which corresponds to index addr */
3380 	while (op <= index) {
3381 		lop = op;
3382 		if (k == XOR_MAX_OPS) {
3383 			k = 0;
3384 			desc = list_entry(desc->chain_node.next,
3385 				struct ppc440spe_adma_desc_slot, chain_node);
3386 			xcb = desc->hw_desc;
3387 
3388 		}
3389 		if ((xcb->ops[k++].h & (DMA_RXOR12 << DMA_CUED_REGION_OFF)) ==
3390 		    (DMA_RXOR12 << DMA_CUED_REGION_OFF))
3391 			op += 2;
3392 		else
3393 			op += 3;
3394 	}
3395 
3396 	BUG_ON(k < 1);
3397 
3398 	if (test_bit(k-1, desc->reverse_flags)) {
3399 		/* reverse operand order; put last op in RXOR group */
3400 		if (index == op - 1)
3401 			ppc440spe_rxor_set_src(desc, k - 1, addr);
3402 	} else {
3403 		/* direct operand order; put first op in RXOR group */
3404 		if (index == lop)
3405 			ppc440spe_rxor_set_src(desc, k - 1, addr);
3406 	}
3407 }
3408 
3409 /**
3410  * ppc440spe_adma_dma2rxor_set_mult - set RXOR multipliers; it's assumed that
3411  *	ppc440spe_adma_dma2rxor_prep_src() has already done prior this call
3412  */
3413 static void ppc440spe_adma_dma2rxor_set_mult(
3414 		struct ppc440spe_adma_desc_slot *desc,
3415 		int index, u8 mult)
3416 {
3417 	struct xor_cb *xcb = desc->hw_desc;
3418 	int k = 0, op = 0, lop = 0;
3419 
3420 	/* get the RXOR operand which corresponds to index mult */
3421 	while (op <= index) {
3422 		lop = op;
3423 		if (k == XOR_MAX_OPS) {
3424 			k = 0;
3425 			desc = list_entry(desc->chain_node.next,
3426 					  struct ppc440spe_adma_desc_slot,
3427 					  chain_node);
3428 			xcb = desc->hw_desc;
3429 
3430 		}
3431 		if ((xcb->ops[k++].h & (DMA_RXOR12 << DMA_CUED_REGION_OFF)) ==
3432 		    (DMA_RXOR12 << DMA_CUED_REGION_OFF))
3433 			op += 2;
3434 		else
3435 			op += 3;
3436 	}
3437 
3438 	BUG_ON(k < 1);
3439 	if (test_bit(k-1, desc->reverse_flags)) {
3440 		/* reverse order */
3441 		ppc440spe_rxor_set_mult(desc, k - 1, op - index - 1, mult);
3442 	} else {
3443 		/* direct order */
3444 		ppc440spe_rxor_set_mult(desc, k - 1, index - lop, mult);
3445 	}
3446 }
3447 
3448 /**
3449  * ppc440spe_init_rxor_cursor -
3450  */
3451 static void ppc440spe_init_rxor_cursor(struct ppc440spe_rxor *cursor)
3452 {
3453 	memset(cursor, 0, sizeof(struct ppc440spe_rxor));
3454 	cursor->state = 2;
3455 }
3456 
3457 /**
3458  * ppc440spe_adma_pq_set_src_mult - set multiplication coefficient into
3459  * descriptor for the PQXOR operation
3460  */
3461 static void ppc440spe_adma_pq_set_src_mult(
3462 		struct ppc440spe_adma_desc_slot *sw_desc,
3463 		unsigned char mult, int index, int dst_pos)
3464 {
3465 	struct ppc440spe_adma_chan *chan;
3466 	u32 mult_idx, mult_dst;
3467 	struct ppc440spe_adma_desc_slot *iter = NULL, *iter1 = NULL;
3468 
3469 	chan = to_ppc440spe_adma_chan(sw_desc->async_tx.chan);
3470 
3471 	switch (chan->device->id) {
3472 	case PPC440SPE_DMA0_ID:
3473 	case PPC440SPE_DMA1_ID:
3474 		if (test_bit(PPC440SPE_DESC_RXOR, &sw_desc->flags)) {
3475 			int region = test_bit(PPC440SPE_DESC_RXOR12,
3476 					&sw_desc->flags) ? 2 : 3;
3477 
3478 			if (index < region) {
3479 				/* RXOR multipliers */
3480 				iter = ppc440spe_get_group_entry(sw_desc,
3481 					sw_desc->dst_cnt - 1);
3482 				if (sw_desc->dst_cnt == 2)
3483 					iter1 = ppc440spe_get_group_entry(
3484 							sw_desc, 0);
3485 
3486 				mult_idx = DMA_CUED_MULT1_OFF + (index << 3);
3487 				mult_dst = DMA_CDB_SG_SRC;
3488 			} else {
3489 				/* WXOR multiplier */
3490 				iter = ppc440spe_get_group_entry(sw_desc,
3491 							index - region +
3492 							sw_desc->dst_cnt);
3493 				mult_idx = DMA_CUED_MULT1_OFF;
3494 				mult_dst = dst_pos ? DMA_CDB_SG_DST2 :
3495 						     DMA_CDB_SG_DST1;
3496 			}
3497 		} else {
3498 			int znum = 0;
3499 
3500 			/* WXOR-only;
3501 			 * skip first slots with destinations (if ZERO_DST has
3502 			 * place)
3503 			 */
3504 			if (test_bit(PPC440SPE_ZERO_P, &sw_desc->flags))
3505 				znum++;
3506 			if (test_bit(PPC440SPE_ZERO_Q, &sw_desc->flags))
3507 				znum++;
3508 
3509 			iter = ppc440spe_get_group_entry(sw_desc, index + znum);
3510 			mult_idx = DMA_CUED_MULT1_OFF;
3511 			mult_dst = dst_pos ? DMA_CDB_SG_DST2 : DMA_CDB_SG_DST1;
3512 		}
3513 
3514 		if (likely(iter)) {
3515 			ppc440spe_desc_set_src_mult(iter, chan,
3516 				mult_idx, mult_dst, mult);
3517 
3518 			if (unlikely(iter1)) {
3519 				/* if we have two destinations for RXOR, then
3520 				 * we've just set Q mult. Set-up P now.
3521 				 */
3522 				ppc440spe_desc_set_src_mult(iter1, chan,
3523 					mult_idx, mult_dst, 1);
3524 			}
3525 
3526 		}
3527 		break;
3528 
3529 	case PPC440SPE_XOR_ID:
3530 		iter = sw_desc->group_head;
3531 		if (sw_desc->dst_cnt == 2) {
3532 			/* both P & Q calculations required; set P mult here */
3533 			ppc440spe_adma_dma2rxor_set_mult(iter, index, 1);
3534 
3535 			/* and then set Q mult */
3536 			iter = ppc440spe_get_group_entry(sw_desc,
3537 			       sw_desc->descs_per_op);
3538 		}
3539 		ppc440spe_adma_dma2rxor_set_mult(iter, index, mult);
3540 		break;
3541 	}
3542 }
3543 
3544 /**
3545  * ppc440spe_adma_free_chan_resources - free the resources allocated
3546  */
3547 static void ppc440spe_adma_free_chan_resources(struct dma_chan *chan)
3548 {
3549 	struct ppc440spe_adma_chan *ppc440spe_chan;
3550 	struct ppc440spe_adma_desc_slot *iter, *_iter;
3551 	int in_use_descs = 0;
3552 
3553 	ppc440spe_chan = to_ppc440spe_adma_chan(chan);
3554 	ppc440spe_adma_slot_cleanup(ppc440spe_chan);
3555 
3556 	spin_lock_bh(&ppc440spe_chan->lock);
3557 	list_for_each_entry_safe(iter, _iter, &ppc440spe_chan->chain,
3558 					chain_node) {
3559 		in_use_descs++;
3560 		list_del(&iter->chain_node);
3561 	}
3562 	list_for_each_entry_safe_reverse(iter, _iter,
3563 			&ppc440spe_chan->all_slots, slot_node) {
3564 		list_del(&iter->slot_node);
3565 		kfree(iter);
3566 		ppc440spe_chan->slots_allocated--;
3567 	}
3568 	ppc440spe_chan->last_used = NULL;
3569 
3570 	dev_dbg(ppc440spe_chan->device->common.dev,
3571 		"ppc440spe adma%d %s slots_allocated %d\n",
3572 		ppc440spe_chan->device->id,
3573 		__func__, ppc440spe_chan->slots_allocated);
3574 	spin_unlock_bh(&ppc440spe_chan->lock);
3575 
3576 	/* one is ok since we left it on there on purpose */
3577 	if (in_use_descs > 1)
3578 		printk(KERN_ERR "SPE: Freeing %d in use descriptors!\n",
3579 			in_use_descs - 1);
3580 }
3581 
3582 /**
3583  * ppc440spe_adma_tx_status - poll the status of an ADMA transaction
3584  * @chan: ADMA channel handle
3585  * @cookie: ADMA transaction identifier
3586  * @txstate: a holder for the current state of the channel
3587  */
3588 static enum dma_status ppc440spe_adma_tx_status(struct dma_chan *chan,
3589 			dma_cookie_t cookie, struct dma_tx_state *txstate)
3590 {
3591 	struct ppc440spe_adma_chan *ppc440spe_chan;
3592 	enum dma_status ret;
3593 
3594 	ppc440spe_chan = to_ppc440spe_adma_chan(chan);
3595 	ret = dma_cookie_status(chan, cookie, txstate);
3596 	if (ret == DMA_COMPLETE)
3597 		return ret;
3598 
3599 	ppc440spe_adma_slot_cleanup(ppc440spe_chan);
3600 
3601 	return dma_cookie_status(chan, cookie, txstate);
3602 }
3603 
3604 /**
3605  * ppc440spe_adma_eot_handler - end of transfer interrupt handler
3606  */
3607 static irqreturn_t ppc440spe_adma_eot_handler(int irq, void *data)
3608 {
3609 	struct ppc440spe_adma_chan *chan = data;
3610 
3611 	dev_dbg(chan->device->common.dev,
3612 		"ppc440spe adma%d: %s\n", chan->device->id, __func__);
3613 
3614 	tasklet_schedule(&chan->irq_tasklet);
3615 	ppc440spe_adma_device_clear_eot_status(chan);
3616 
3617 	return IRQ_HANDLED;
3618 }
3619 
3620 /**
3621  * ppc440spe_adma_err_handler - DMA error interrupt handler;
3622  *	do the same things as a eot handler
3623  */
3624 static irqreturn_t ppc440spe_adma_err_handler(int irq, void *data)
3625 {
3626 	struct ppc440spe_adma_chan *chan = data;
3627 
3628 	dev_dbg(chan->device->common.dev,
3629 		"ppc440spe adma%d: %s\n", chan->device->id, __func__);
3630 
3631 	tasklet_schedule(&chan->irq_tasklet);
3632 	ppc440spe_adma_device_clear_eot_status(chan);
3633 
3634 	return IRQ_HANDLED;
3635 }
3636 
3637 /**
3638  * ppc440spe_test_callback - called when test operation has been done
3639  */
3640 static void ppc440spe_test_callback(void *unused)
3641 {
3642 	complete(&ppc440spe_r6_test_comp);
3643 }
3644 
3645 /**
3646  * ppc440spe_adma_issue_pending - flush all pending descriptors to h/w
3647  */
3648 static void ppc440spe_adma_issue_pending(struct dma_chan *chan)
3649 {
3650 	struct ppc440spe_adma_chan *ppc440spe_chan;
3651 
3652 	ppc440spe_chan = to_ppc440spe_adma_chan(chan);
3653 	dev_dbg(ppc440spe_chan->device->common.dev,
3654 		"ppc440spe adma%d: %s %d \n", ppc440spe_chan->device->id,
3655 		__func__, ppc440spe_chan->pending);
3656 
3657 	if (ppc440spe_chan->pending) {
3658 		ppc440spe_chan->pending = 0;
3659 		ppc440spe_chan_append(ppc440spe_chan);
3660 	}
3661 }
3662 
3663 /**
3664  * ppc440spe_chan_start_null_xor - initiate the first XOR operation (DMA engines
3665  *	use FIFOs (as opposite to chains used in XOR) so this is a XOR
3666  *	specific operation)
3667  */
3668 static void ppc440spe_chan_start_null_xor(struct ppc440spe_adma_chan *chan)
3669 {
3670 	struct ppc440spe_adma_desc_slot *sw_desc, *group_start;
3671 	dma_cookie_t cookie;
3672 	int slot_cnt, slots_per_op;
3673 
3674 	dev_dbg(chan->device->common.dev,
3675 		"ppc440spe adma%d: %s\n", chan->device->id, __func__);
3676 
3677 	spin_lock_bh(&chan->lock);
3678 	slot_cnt = ppc440spe_chan_xor_slot_count(0, 2, &slots_per_op);
3679 	sw_desc = ppc440spe_adma_alloc_slots(chan, slot_cnt, slots_per_op);
3680 	if (sw_desc) {
3681 		group_start = sw_desc->group_head;
3682 		list_splice_init(&sw_desc->group_list, &chan->chain);
3683 		async_tx_ack(&sw_desc->async_tx);
3684 		ppc440spe_desc_init_null_xor(group_start);
3685 
3686 		cookie = dma_cookie_assign(&sw_desc->async_tx);
3687 
3688 		/* initialize the completed cookie to be less than
3689 		 * the most recently used cookie
3690 		 */
3691 		chan->common.completed_cookie = cookie - 1;
3692 
3693 		/* channel should not be busy */
3694 		BUG_ON(ppc440spe_chan_is_busy(chan));
3695 
3696 		/* set the descriptor address */
3697 		ppc440spe_chan_set_first_xor_descriptor(chan, sw_desc);
3698 
3699 		/* run the descriptor */
3700 		ppc440spe_chan_run(chan);
3701 	} else
3702 		printk(KERN_ERR "ppc440spe adma%d"
3703 			" failed to allocate null descriptor\n",
3704 			chan->device->id);
3705 	spin_unlock_bh(&chan->lock);
3706 }
3707 
3708 /**
3709  * ppc440spe_test_raid6 - test are RAID-6 capabilities enabled successfully.
3710  *	For this we just perform one WXOR operation with the same source
3711  *	and destination addresses, the GF-multiplier is 1; so if RAID-6
3712  *	capabilities are enabled then we'll get src/dst filled with zero.
3713  */
3714 static int ppc440spe_test_raid6(struct ppc440spe_adma_chan *chan)
3715 {
3716 	struct ppc440spe_adma_desc_slot *sw_desc, *iter;
3717 	struct page *pg;
3718 	char *a;
3719 	dma_addr_t dma_addr, addrs[2];
3720 	unsigned long op = 0;
3721 	int rval = 0;
3722 
3723 	set_bit(PPC440SPE_DESC_WXOR, &op);
3724 
3725 	pg = alloc_page(GFP_KERNEL);
3726 	if (!pg)
3727 		return -ENOMEM;
3728 
3729 	spin_lock_bh(&chan->lock);
3730 	sw_desc = ppc440spe_adma_alloc_slots(chan, 1, 1);
3731 	if (sw_desc) {
3732 		/* 1 src, 1 dsr, int_ena, WXOR */
3733 		ppc440spe_desc_init_dma01pq(sw_desc, 1, 1, 1, op);
3734 		list_for_each_entry(iter, &sw_desc->group_list, chain_node) {
3735 			ppc440spe_desc_set_byte_count(iter, chan, PAGE_SIZE);
3736 			iter->unmap_len = PAGE_SIZE;
3737 		}
3738 	} else {
3739 		rval = -EFAULT;
3740 		spin_unlock_bh(&chan->lock);
3741 		goto exit;
3742 	}
3743 	spin_unlock_bh(&chan->lock);
3744 
3745 	/* Fill the test page with ones */
3746 	memset(page_address(pg), 0xFF, PAGE_SIZE);
3747 	dma_addr = dma_map_page(chan->device->dev, pg, 0,
3748 				PAGE_SIZE, DMA_BIDIRECTIONAL);
3749 
3750 	/* Setup addresses */
3751 	ppc440spe_adma_pq_set_src(sw_desc, dma_addr, 0);
3752 	ppc440spe_adma_pq_set_src_mult(sw_desc, 1, 0, 0);
3753 	addrs[0] = dma_addr;
3754 	addrs[1] = 0;
3755 	ppc440spe_adma_pq_set_dest(sw_desc, addrs, DMA_PREP_PQ_DISABLE_Q);
3756 
3757 	async_tx_ack(&sw_desc->async_tx);
3758 	sw_desc->async_tx.callback = ppc440spe_test_callback;
3759 	sw_desc->async_tx.callback_param = NULL;
3760 
3761 	init_completion(&ppc440spe_r6_test_comp);
3762 
3763 	ppc440spe_adma_tx_submit(&sw_desc->async_tx);
3764 	ppc440spe_adma_issue_pending(&chan->common);
3765 
3766 	wait_for_completion(&ppc440spe_r6_test_comp);
3767 
3768 	/* Now check if the test page is zeroed */
3769 	a = page_address(pg);
3770 	if ((*(u32 *)a) == 0 && memcmp(a, a+4, PAGE_SIZE-4) == 0) {
3771 		/* page is zero - RAID-6 enabled */
3772 		rval = 0;
3773 	} else {
3774 		/* RAID-6 was not enabled */
3775 		rval = -EINVAL;
3776 	}
3777 exit:
3778 	__free_page(pg);
3779 	return rval;
3780 }
3781 
3782 static void ppc440spe_adma_init_capabilities(struct ppc440spe_adma_device *adev)
3783 {
3784 	switch (adev->id) {
3785 	case PPC440SPE_DMA0_ID:
3786 	case PPC440SPE_DMA1_ID:
3787 		dma_cap_set(DMA_MEMCPY, adev->common.cap_mask);
3788 		dma_cap_set(DMA_INTERRUPT, adev->common.cap_mask);
3789 		dma_cap_set(DMA_PQ, adev->common.cap_mask);
3790 		dma_cap_set(DMA_PQ_VAL, adev->common.cap_mask);
3791 		dma_cap_set(DMA_XOR_VAL, adev->common.cap_mask);
3792 		break;
3793 	case PPC440SPE_XOR_ID:
3794 		dma_cap_set(DMA_XOR, adev->common.cap_mask);
3795 		dma_cap_set(DMA_PQ, adev->common.cap_mask);
3796 		dma_cap_set(DMA_INTERRUPT, adev->common.cap_mask);
3797 		adev->common.cap_mask = adev->common.cap_mask;
3798 		break;
3799 	}
3800 
3801 	/* Set base routines */
3802 	adev->common.device_alloc_chan_resources =
3803 				ppc440spe_adma_alloc_chan_resources;
3804 	adev->common.device_free_chan_resources =
3805 				ppc440spe_adma_free_chan_resources;
3806 	adev->common.device_tx_status = ppc440spe_adma_tx_status;
3807 	adev->common.device_issue_pending = ppc440spe_adma_issue_pending;
3808 
3809 	/* Set prep routines based on capability */
3810 	if (dma_has_cap(DMA_MEMCPY, adev->common.cap_mask)) {
3811 		adev->common.device_prep_dma_memcpy =
3812 			ppc440spe_adma_prep_dma_memcpy;
3813 	}
3814 	if (dma_has_cap(DMA_XOR, adev->common.cap_mask)) {
3815 		adev->common.max_xor = XOR_MAX_OPS;
3816 		adev->common.device_prep_dma_xor =
3817 			ppc440spe_adma_prep_dma_xor;
3818 	}
3819 	if (dma_has_cap(DMA_PQ, adev->common.cap_mask)) {
3820 		switch (adev->id) {
3821 		case PPC440SPE_DMA0_ID:
3822 			dma_set_maxpq(&adev->common,
3823 				DMA0_FIFO_SIZE / sizeof(struct dma_cdb), 0);
3824 			break;
3825 		case PPC440SPE_DMA1_ID:
3826 			dma_set_maxpq(&adev->common,
3827 				DMA1_FIFO_SIZE / sizeof(struct dma_cdb), 0);
3828 			break;
3829 		case PPC440SPE_XOR_ID:
3830 			adev->common.max_pq = XOR_MAX_OPS * 3;
3831 			break;
3832 		}
3833 		adev->common.device_prep_dma_pq =
3834 			ppc440spe_adma_prep_dma_pq;
3835 	}
3836 	if (dma_has_cap(DMA_PQ_VAL, adev->common.cap_mask)) {
3837 		switch (adev->id) {
3838 		case PPC440SPE_DMA0_ID:
3839 			adev->common.max_pq = DMA0_FIFO_SIZE /
3840 						sizeof(struct dma_cdb);
3841 			break;
3842 		case PPC440SPE_DMA1_ID:
3843 			adev->common.max_pq = DMA1_FIFO_SIZE /
3844 						sizeof(struct dma_cdb);
3845 			break;
3846 		}
3847 		adev->common.device_prep_dma_pq_val =
3848 			ppc440spe_adma_prep_dma_pqzero_sum;
3849 	}
3850 	if (dma_has_cap(DMA_XOR_VAL, adev->common.cap_mask)) {
3851 		switch (adev->id) {
3852 		case PPC440SPE_DMA0_ID:
3853 			adev->common.max_xor = DMA0_FIFO_SIZE /
3854 						sizeof(struct dma_cdb);
3855 			break;
3856 		case PPC440SPE_DMA1_ID:
3857 			adev->common.max_xor = DMA1_FIFO_SIZE /
3858 						sizeof(struct dma_cdb);
3859 			break;
3860 		}
3861 		adev->common.device_prep_dma_xor_val =
3862 			ppc440spe_adma_prep_dma_xor_zero_sum;
3863 	}
3864 	if (dma_has_cap(DMA_INTERRUPT, adev->common.cap_mask)) {
3865 		adev->common.device_prep_dma_interrupt =
3866 			ppc440spe_adma_prep_dma_interrupt;
3867 	}
3868 	pr_info("%s: AMCC(R) PPC440SP(E) ADMA Engine: "
3869 	  "( %s%s%s%s%s%s)\n",
3870 	  dev_name(adev->dev),
3871 	  dma_has_cap(DMA_PQ, adev->common.cap_mask) ? "pq " : "",
3872 	  dma_has_cap(DMA_PQ_VAL, adev->common.cap_mask) ? "pq_val " : "",
3873 	  dma_has_cap(DMA_XOR, adev->common.cap_mask) ? "xor " : "",
3874 	  dma_has_cap(DMA_XOR_VAL, adev->common.cap_mask) ? "xor_val " : "",
3875 	  dma_has_cap(DMA_MEMCPY, adev->common.cap_mask) ? "memcpy " : "",
3876 	  dma_has_cap(DMA_INTERRUPT, adev->common.cap_mask) ? "intr " : "");
3877 }
3878 
3879 static int ppc440spe_adma_setup_irqs(struct ppc440spe_adma_device *adev,
3880 				     struct ppc440spe_adma_chan *chan,
3881 				     int *initcode)
3882 {
3883 	struct platform_device *ofdev;
3884 	struct device_node *np;
3885 	int ret;
3886 
3887 	ofdev = container_of(adev->dev, struct platform_device, dev);
3888 	np = ofdev->dev.of_node;
3889 	if (adev->id != PPC440SPE_XOR_ID) {
3890 		adev->err_irq = irq_of_parse_and_map(np, 1);
3891 		if (!adev->err_irq) {
3892 			dev_warn(adev->dev, "no err irq resource?\n");
3893 			*initcode = PPC_ADMA_INIT_IRQ2;
3894 			adev->err_irq = -ENXIO;
3895 		} else
3896 			atomic_inc(&ppc440spe_adma_err_irq_ref);
3897 	} else {
3898 		adev->err_irq = -ENXIO;
3899 	}
3900 
3901 	adev->irq = irq_of_parse_and_map(np, 0);
3902 	if (!adev->irq) {
3903 		dev_err(adev->dev, "no irq resource\n");
3904 		*initcode = PPC_ADMA_INIT_IRQ1;
3905 		ret = -ENXIO;
3906 		goto err_irq_map;
3907 	}
3908 	dev_dbg(adev->dev, "irq %d, err irq %d\n",
3909 		adev->irq, adev->err_irq);
3910 
3911 	ret = request_irq(adev->irq, ppc440spe_adma_eot_handler,
3912 			  0, dev_driver_string(adev->dev), chan);
3913 	if (ret) {
3914 		dev_err(adev->dev, "can't request irq %d\n",
3915 			adev->irq);
3916 		*initcode = PPC_ADMA_INIT_IRQ1;
3917 		ret = -EIO;
3918 		goto err_req1;
3919 	}
3920 
3921 	/* only DMA engines have a separate error IRQ
3922 	 * so it's Ok if err_irq < 0 in XOR engine case.
3923 	 */
3924 	if (adev->err_irq > 0) {
3925 		/* both DMA engines share common error IRQ */
3926 		ret = request_irq(adev->err_irq,
3927 				  ppc440spe_adma_err_handler,
3928 				  IRQF_SHARED,
3929 				  dev_driver_string(adev->dev),
3930 				  chan);
3931 		if (ret) {
3932 			dev_err(adev->dev, "can't request irq %d\n",
3933 				adev->err_irq);
3934 			*initcode = PPC_ADMA_INIT_IRQ2;
3935 			ret = -EIO;
3936 			goto err_req2;
3937 		}
3938 	}
3939 
3940 	if (adev->id == PPC440SPE_XOR_ID) {
3941 		/* enable XOR engine interrupts */
3942 		iowrite32be(XOR_IE_CBCIE_BIT | XOR_IE_ICBIE_BIT |
3943 			    XOR_IE_ICIE_BIT | XOR_IE_RPTIE_BIT,
3944 			    &adev->xor_reg->ier);
3945 	} else {
3946 		u32 mask, enable;
3947 
3948 		np = of_find_compatible_node(NULL, NULL, "ibm,i2o-440spe");
3949 		if (!np) {
3950 			pr_err("%s: can't find I2O device tree node\n",
3951 				__func__);
3952 			ret = -ENODEV;
3953 			goto err_req2;
3954 		}
3955 		adev->i2o_reg = of_iomap(np, 0);
3956 		if (!adev->i2o_reg) {
3957 			pr_err("%s: failed to map I2O registers\n", __func__);
3958 			of_node_put(np);
3959 			ret = -EINVAL;
3960 			goto err_req2;
3961 		}
3962 		of_node_put(np);
3963 		/* Unmask 'CS FIFO Attention' interrupts and
3964 		 * enable generating interrupts on errors
3965 		 */
3966 		enable = (adev->id == PPC440SPE_DMA0_ID) ?
3967 			 ~(I2O_IOPIM_P0SNE | I2O_IOPIM_P0EM) :
3968 			 ~(I2O_IOPIM_P1SNE | I2O_IOPIM_P1EM);
3969 		mask = ioread32(&adev->i2o_reg->iopim) & enable;
3970 		iowrite32(mask, &adev->i2o_reg->iopim);
3971 	}
3972 	return 0;
3973 
3974 err_req2:
3975 	free_irq(adev->irq, chan);
3976 err_req1:
3977 	irq_dispose_mapping(adev->irq);
3978 err_irq_map:
3979 	if (adev->err_irq > 0) {
3980 		if (atomic_dec_and_test(&ppc440spe_adma_err_irq_ref))
3981 			irq_dispose_mapping(adev->err_irq);
3982 	}
3983 	return ret;
3984 }
3985 
3986 static void ppc440spe_adma_release_irqs(struct ppc440spe_adma_device *adev,
3987 					struct ppc440spe_adma_chan *chan)
3988 {
3989 	u32 mask, disable;
3990 
3991 	if (adev->id == PPC440SPE_XOR_ID) {
3992 		/* disable XOR engine interrupts */
3993 		mask = ioread32be(&adev->xor_reg->ier);
3994 		mask &= ~(XOR_IE_CBCIE_BIT | XOR_IE_ICBIE_BIT |
3995 			  XOR_IE_ICIE_BIT | XOR_IE_RPTIE_BIT);
3996 		iowrite32be(mask, &adev->xor_reg->ier);
3997 	} else {
3998 		/* disable DMAx engine interrupts */
3999 		disable = (adev->id == PPC440SPE_DMA0_ID) ?
4000 			  (I2O_IOPIM_P0SNE | I2O_IOPIM_P0EM) :
4001 			  (I2O_IOPIM_P1SNE | I2O_IOPIM_P1EM);
4002 		mask = ioread32(&adev->i2o_reg->iopim) | disable;
4003 		iowrite32(mask, &adev->i2o_reg->iopim);
4004 	}
4005 	free_irq(adev->irq, chan);
4006 	irq_dispose_mapping(adev->irq);
4007 	if (adev->err_irq > 0) {
4008 		free_irq(adev->err_irq, chan);
4009 		if (atomic_dec_and_test(&ppc440spe_adma_err_irq_ref)) {
4010 			irq_dispose_mapping(adev->err_irq);
4011 			iounmap(adev->i2o_reg);
4012 		}
4013 	}
4014 }
4015 
4016 /**
4017  * ppc440spe_adma_probe - probe the asynch device
4018  */
4019 static int ppc440spe_adma_probe(struct platform_device *ofdev)
4020 {
4021 	struct device_node *np = ofdev->dev.of_node;
4022 	struct resource res;
4023 	struct ppc440spe_adma_device *adev;
4024 	struct ppc440spe_adma_chan *chan;
4025 	struct ppc_dma_chan_ref *ref, *_ref;
4026 	int ret = 0, initcode = PPC_ADMA_INIT_OK;
4027 	const u32 *idx;
4028 	int len;
4029 	void *regs;
4030 	u32 id, pool_size;
4031 
4032 	if (of_device_is_compatible(np, "amcc,xor-accelerator")) {
4033 		id = PPC440SPE_XOR_ID;
4034 		/* As far as the XOR engine is concerned, it does not
4035 		 * use FIFOs but uses linked list. So there is no dependency
4036 		 * between pool size to allocate and the engine configuration.
4037 		 */
4038 		pool_size = PAGE_SIZE << 1;
4039 	} else {
4040 		/* it is DMA0 or DMA1 */
4041 		idx = of_get_property(np, "cell-index", &len);
4042 		if (!idx || (len != sizeof(u32))) {
4043 			dev_err(&ofdev->dev, "Device node %pOF has missing "
4044 				"or invalid cell-index property\n",
4045 				np);
4046 			return -EINVAL;
4047 		}
4048 		id = *idx;
4049 		/* DMA0,1 engines use FIFO to maintain CDBs, so we
4050 		 * should allocate the pool accordingly to size of this
4051 		 * FIFO. Thus, the pool size depends on the FIFO depth:
4052 		 * how much CDBs pointers the FIFO may contain then so
4053 		 * much CDBs we should provide in the pool.
4054 		 * That is
4055 		 *   CDB size = 32B;
4056 		 *   CDBs number = (DMA0_FIFO_SIZE >> 3);
4057 		 *   Pool size = CDBs number * CDB size =
4058 		 *      = (DMA0_FIFO_SIZE >> 3) << 5 = DMA0_FIFO_SIZE << 2.
4059 		 */
4060 		pool_size = (id == PPC440SPE_DMA0_ID) ?
4061 			    DMA0_FIFO_SIZE : DMA1_FIFO_SIZE;
4062 		pool_size <<= 2;
4063 	}
4064 
4065 	if (of_address_to_resource(np, 0, &res)) {
4066 		dev_err(&ofdev->dev, "failed to get memory resource\n");
4067 		initcode = PPC_ADMA_INIT_MEMRES;
4068 		ret = -ENODEV;
4069 		goto out;
4070 	}
4071 
4072 	if (!request_mem_region(res.start, resource_size(&res),
4073 				dev_driver_string(&ofdev->dev))) {
4074 		dev_err(&ofdev->dev, "failed to request memory region %pR\n",
4075 			&res);
4076 		initcode = PPC_ADMA_INIT_MEMREG;
4077 		ret = -EBUSY;
4078 		goto out;
4079 	}
4080 
4081 	/* create a device */
4082 	adev = kzalloc(sizeof(*adev), GFP_KERNEL);
4083 	if (!adev) {
4084 		initcode = PPC_ADMA_INIT_ALLOC;
4085 		ret = -ENOMEM;
4086 		goto err_adev_alloc;
4087 	}
4088 
4089 	adev->id = id;
4090 	adev->pool_size = pool_size;
4091 	/* allocate coherent memory for hardware descriptors */
4092 	adev->dma_desc_pool_virt = dma_alloc_coherent(&ofdev->dev,
4093 					adev->pool_size, &adev->dma_desc_pool,
4094 					GFP_KERNEL);
4095 	if (adev->dma_desc_pool_virt == NULL) {
4096 		dev_err(&ofdev->dev, "failed to allocate %d bytes of coherent "
4097 			"memory for hardware descriptors\n",
4098 			adev->pool_size);
4099 		initcode = PPC_ADMA_INIT_COHERENT;
4100 		ret = -ENOMEM;
4101 		goto err_dma_alloc;
4102 	}
4103 	dev_dbg(&ofdev->dev, "allocated descriptor pool virt 0x%p phys 0x%llx\n",
4104 		adev->dma_desc_pool_virt, (u64)adev->dma_desc_pool);
4105 
4106 	regs = ioremap(res.start, resource_size(&res));
4107 	if (!regs) {
4108 		dev_err(&ofdev->dev, "failed to ioremap regs!\n");
4109 		ret = -ENOMEM;
4110 		goto err_regs_alloc;
4111 	}
4112 
4113 	if (adev->id == PPC440SPE_XOR_ID) {
4114 		adev->xor_reg = regs;
4115 		/* Reset XOR */
4116 		iowrite32be(XOR_CRSR_XASR_BIT, &adev->xor_reg->crsr);
4117 		iowrite32be(XOR_CRSR_64BA_BIT, &adev->xor_reg->crrr);
4118 	} else {
4119 		size_t fifo_size = (adev->id == PPC440SPE_DMA0_ID) ?
4120 				   DMA0_FIFO_SIZE : DMA1_FIFO_SIZE;
4121 		adev->dma_reg = regs;
4122 		/* DMAx_FIFO_SIZE is defined in bytes,
4123 		 * <fsiz> - is defined in number of CDB pointers (8byte).
4124 		 * DMA FIFO Length = CSlength + CPlength, where
4125 		 * CSlength = CPlength = (fsiz + 1) * 8.
4126 		 */
4127 		iowrite32(DMA_FIFO_ENABLE | ((fifo_size >> 3) - 2),
4128 			  &adev->dma_reg->fsiz);
4129 		/* Configure DMA engine */
4130 		iowrite32(DMA_CFG_DXEPR_HP | DMA_CFG_DFMPP_HP | DMA_CFG_FALGN,
4131 			  &adev->dma_reg->cfg);
4132 		/* Clear Status */
4133 		iowrite32(~0, &adev->dma_reg->dsts);
4134 	}
4135 
4136 	adev->dev = &ofdev->dev;
4137 	adev->common.dev = &ofdev->dev;
4138 	INIT_LIST_HEAD(&adev->common.channels);
4139 	platform_set_drvdata(ofdev, adev);
4140 
4141 	/* create a channel */
4142 	chan = kzalloc(sizeof(*chan), GFP_KERNEL);
4143 	if (!chan) {
4144 		initcode = PPC_ADMA_INIT_CHANNEL;
4145 		ret = -ENOMEM;
4146 		goto err_chan_alloc;
4147 	}
4148 
4149 	spin_lock_init(&chan->lock);
4150 	INIT_LIST_HEAD(&chan->chain);
4151 	INIT_LIST_HEAD(&chan->all_slots);
4152 	chan->device = adev;
4153 	chan->common.device = &adev->common;
4154 	dma_cookie_init(&chan->common);
4155 	list_add_tail(&chan->common.device_node, &adev->common.channels);
4156 	tasklet_init(&chan->irq_tasklet, ppc440spe_adma_tasklet,
4157 		     (unsigned long)chan);
4158 
4159 	/* allocate and map helper pages for async validation or
4160 	 * async_mult/async_sum_product operations on DMA0/1.
4161 	 */
4162 	if (adev->id != PPC440SPE_XOR_ID) {
4163 		chan->pdest_page = alloc_page(GFP_KERNEL);
4164 		chan->qdest_page = alloc_page(GFP_KERNEL);
4165 		if (!chan->pdest_page ||
4166 		    !chan->qdest_page) {
4167 			if (chan->pdest_page)
4168 				__free_page(chan->pdest_page);
4169 			if (chan->qdest_page)
4170 				__free_page(chan->qdest_page);
4171 			ret = -ENOMEM;
4172 			goto err_page_alloc;
4173 		}
4174 		chan->pdest = dma_map_page(&ofdev->dev, chan->pdest_page, 0,
4175 					   PAGE_SIZE, DMA_BIDIRECTIONAL);
4176 		chan->qdest = dma_map_page(&ofdev->dev, chan->qdest_page, 0,
4177 					   PAGE_SIZE, DMA_BIDIRECTIONAL);
4178 	}
4179 
4180 	ref = kmalloc(sizeof(*ref), GFP_KERNEL);
4181 	if (ref) {
4182 		ref->chan = &chan->common;
4183 		INIT_LIST_HEAD(&ref->node);
4184 		list_add_tail(&ref->node, &ppc440spe_adma_chan_list);
4185 	} else {
4186 		dev_err(&ofdev->dev, "failed to allocate channel reference!\n");
4187 		ret = -ENOMEM;
4188 		goto err_ref_alloc;
4189 	}
4190 
4191 	ret = ppc440spe_adma_setup_irqs(adev, chan, &initcode);
4192 	if (ret)
4193 		goto err_irq;
4194 
4195 	ppc440spe_adma_init_capabilities(adev);
4196 
4197 	ret = dma_async_device_register(&adev->common);
4198 	if (ret) {
4199 		initcode = PPC_ADMA_INIT_REGISTER;
4200 		dev_err(&ofdev->dev, "failed to register dma device\n");
4201 		goto err_dev_reg;
4202 	}
4203 
4204 	goto out;
4205 
4206 err_dev_reg:
4207 	ppc440spe_adma_release_irqs(adev, chan);
4208 err_irq:
4209 	list_for_each_entry_safe(ref, _ref, &ppc440spe_adma_chan_list, node) {
4210 		if (chan == to_ppc440spe_adma_chan(ref->chan)) {
4211 			list_del(&ref->node);
4212 			kfree(ref);
4213 		}
4214 	}
4215 err_ref_alloc:
4216 	if (adev->id != PPC440SPE_XOR_ID) {
4217 		dma_unmap_page(&ofdev->dev, chan->pdest,
4218 			       PAGE_SIZE, DMA_BIDIRECTIONAL);
4219 		dma_unmap_page(&ofdev->dev, chan->qdest,
4220 			       PAGE_SIZE, DMA_BIDIRECTIONAL);
4221 		__free_page(chan->pdest_page);
4222 		__free_page(chan->qdest_page);
4223 	}
4224 err_page_alloc:
4225 	kfree(chan);
4226 err_chan_alloc:
4227 	if (adev->id == PPC440SPE_XOR_ID)
4228 		iounmap(adev->xor_reg);
4229 	else
4230 		iounmap(adev->dma_reg);
4231 err_regs_alloc:
4232 	dma_free_coherent(adev->dev, adev->pool_size,
4233 			  adev->dma_desc_pool_virt,
4234 			  adev->dma_desc_pool);
4235 err_dma_alloc:
4236 	kfree(adev);
4237 err_adev_alloc:
4238 	release_mem_region(res.start, resource_size(&res));
4239 out:
4240 	if (id < PPC440SPE_ADMA_ENGINES_NUM)
4241 		ppc440spe_adma_devices[id] = initcode;
4242 
4243 	return ret;
4244 }
4245 
4246 /**
4247  * ppc440spe_adma_remove - remove the asynch device
4248  */
4249 static int ppc440spe_adma_remove(struct platform_device *ofdev)
4250 {
4251 	struct ppc440spe_adma_device *adev = platform_get_drvdata(ofdev);
4252 	struct device_node *np = ofdev->dev.of_node;
4253 	struct resource res;
4254 	struct dma_chan *chan, *_chan;
4255 	struct ppc_dma_chan_ref *ref, *_ref;
4256 	struct ppc440spe_adma_chan *ppc440spe_chan;
4257 
4258 	if (adev->id < PPC440SPE_ADMA_ENGINES_NUM)
4259 		ppc440spe_adma_devices[adev->id] = -1;
4260 
4261 	dma_async_device_unregister(&adev->common);
4262 
4263 	list_for_each_entry_safe(chan, _chan, &adev->common.channels,
4264 				 device_node) {
4265 		ppc440spe_chan = to_ppc440spe_adma_chan(chan);
4266 		ppc440spe_adma_release_irqs(adev, ppc440spe_chan);
4267 		tasklet_kill(&ppc440spe_chan->irq_tasklet);
4268 		if (adev->id != PPC440SPE_XOR_ID) {
4269 			dma_unmap_page(&ofdev->dev, ppc440spe_chan->pdest,
4270 					PAGE_SIZE, DMA_BIDIRECTIONAL);
4271 			dma_unmap_page(&ofdev->dev, ppc440spe_chan->qdest,
4272 					PAGE_SIZE, DMA_BIDIRECTIONAL);
4273 			__free_page(ppc440spe_chan->pdest_page);
4274 			__free_page(ppc440spe_chan->qdest_page);
4275 		}
4276 		list_for_each_entry_safe(ref, _ref, &ppc440spe_adma_chan_list,
4277 					 node) {
4278 			if (ppc440spe_chan ==
4279 			    to_ppc440spe_adma_chan(ref->chan)) {
4280 				list_del(&ref->node);
4281 				kfree(ref);
4282 			}
4283 		}
4284 		list_del(&chan->device_node);
4285 		kfree(ppc440spe_chan);
4286 	}
4287 
4288 	dma_free_coherent(adev->dev, adev->pool_size,
4289 			  adev->dma_desc_pool_virt, adev->dma_desc_pool);
4290 	if (adev->id == PPC440SPE_XOR_ID)
4291 		iounmap(adev->xor_reg);
4292 	else
4293 		iounmap(adev->dma_reg);
4294 	of_address_to_resource(np, 0, &res);
4295 	release_mem_region(res.start, resource_size(&res));
4296 	kfree(adev);
4297 	return 0;
4298 }
4299 
4300 /*
4301  * /sys driver interface to enable h/w RAID-6 capabilities
4302  * Files created in e.g. /sys/devices/plb.0/400100100.dma0/driver/
4303  * directory are "devices", "enable" and "poly".
4304  * "devices" shows available engines.
4305  * "enable" is used to enable RAID-6 capabilities or to check
4306  * whether these has been activated.
4307  * "poly" allows setting/checking used polynomial (for PPC440SPe only).
4308  */
4309 
4310 static ssize_t devices_show(struct device_driver *dev, char *buf)
4311 {
4312 	ssize_t size = 0;
4313 	int i;
4314 
4315 	for (i = 0; i < PPC440SPE_ADMA_ENGINES_NUM; i++) {
4316 		if (ppc440spe_adma_devices[i] == -1)
4317 			continue;
4318 		size += snprintf(buf + size, PAGE_SIZE - size,
4319 				 "PPC440SP(E)-ADMA.%d: %s\n", i,
4320 				 ppc_adma_errors[ppc440spe_adma_devices[i]]);
4321 	}
4322 	return size;
4323 }
4324 static DRIVER_ATTR_RO(devices);
4325 
4326 static ssize_t enable_show(struct device_driver *dev, char *buf)
4327 {
4328 	return snprintf(buf, PAGE_SIZE,
4329 			"PPC440SP(e) RAID-6 capabilities are %sABLED.\n",
4330 			ppc440spe_r6_enabled ? "EN" : "DIS");
4331 }
4332 
4333 static ssize_t enable_store(struct device_driver *dev, const char *buf,
4334 			    size_t count)
4335 {
4336 	unsigned long val;
4337 
4338 	if (!count || count > 11)
4339 		return -EINVAL;
4340 
4341 	if (!ppc440spe_r6_tchan)
4342 		return -EFAULT;
4343 
4344 	/* Write a key */
4345 	sscanf(buf, "%lx", &val);
4346 	dcr_write(ppc440spe_mq_dcr_host, DCRN_MQ0_XORBA, val);
4347 	isync();
4348 
4349 	/* Verify whether it really works now */
4350 	if (ppc440spe_test_raid6(ppc440spe_r6_tchan) == 0) {
4351 		pr_info("PPC440SP(e) RAID-6 has been activated "
4352 			"successfully\n");
4353 		ppc440spe_r6_enabled = 1;
4354 	} else {
4355 		pr_info("PPC440SP(e) RAID-6 hasn't been activated!"
4356 			" Error key ?\n");
4357 		ppc440spe_r6_enabled = 0;
4358 	}
4359 	return count;
4360 }
4361 static DRIVER_ATTR_RW(enable);
4362 
4363 static ssize_t poly_show(struct device_driver *dev, char *buf)
4364 {
4365 	ssize_t size = 0;
4366 	u32 reg;
4367 
4368 #ifdef CONFIG_440SP
4369 	/* 440SP has fixed polynomial */
4370 	reg = 0x4d;
4371 #else
4372 	reg = dcr_read(ppc440spe_mq_dcr_host, DCRN_MQ0_CFBHL);
4373 	reg >>= MQ0_CFBHL_POLY;
4374 	reg &= 0xFF;
4375 #endif
4376 
4377 	size = snprintf(buf, PAGE_SIZE, "PPC440SP(e) RAID-6 driver "
4378 			"uses 0x1%02x polynomial.\n", reg);
4379 	return size;
4380 }
4381 
4382 static ssize_t poly_store(struct device_driver *dev, const char *buf,
4383 			  size_t count)
4384 {
4385 	unsigned long reg, val;
4386 
4387 #ifdef CONFIG_440SP
4388 	/* 440SP uses default 0x14D polynomial only */
4389 	return -EINVAL;
4390 #endif
4391 
4392 	if (!count || count > 6)
4393 		return -EINVAL;
4394 
4395 	/* e.g., 0x14D or 0x11D */
4396 	sscanf(buf, "%lx", &val);
4397 
4398 	if (val & ~0x1FF)
4399 		return -EINVAL;
4400 
4401 	val &= 0xFF;
4402 	reg = dcr_read(ppc440spe_mq_dcr_host, DCRN_MQ0_CFBHL);
4403 	reg &= ~(0xFF << MQ0_CFBHL_POLY);
4404 	reg |= val << MQ0_CFBHL_POLY;
4405 	dcr_write(ppc440spe_mq_dcr_host, DCRN_MQ0_CFBHL, reg);
4406 
4407 	return count;
4408 }
4409 static DRIVER_ATTR_RW(poly);
4410 
4411 /*
4412  * Common initialisation for RAID engines; allocate memory for
4413  * DMAx FIFOs, perform configuration common for all DMA engines.
4414  * Further DMA engine specific configuration is done at probe time.
4415  */
4416 static int ppc440spe_configure_raid_devices(void)
4417 {
4418 	struct device_node *np;
4419 	struct resource i2o_res;
4420 	struct i2o_regs __iomem *i2o_reg;
4421 	dcr_host_t i2o_dcr_host;
4422 	unsigned int dcr_base, dcr_len;
4423 	int i, ret;
4424 
4425 	np = of_find_compatible_node(NULL, NULL, "ibm,i2o-440spe");
4426 	if (!np) {
4427 		pr_err("%s: can't find I2O device tree node\n",
4428 			__func__);
4429 		return -ENODEV;
4430 	}
4431 
4432 	if (of_address_to_resource(np, 0, &i2o_res)) {
4433 		of_node_put(np);
4434 		return -EINVAL;
4435 	}
4436 
4437 	i2o_reg = of_iomap(np, 0);
4438 	if (!i2o_reg) {
4439 		pr_err("%s: failed to map I2O registers\n", __func__);
4440 		of_node_put(np);
4441 		return -EINVAL;
4442 	}
4443 
4444 	/* Get I2O DCRs base */
4445 	dcr_base = dcr_resource_start(np, 0);
4446 	dcr_len = dcr_resource_len(np, 0);
4447 	if (!dcr_base && !dcr_len) {
4448 		pr_err("%pOF: can't get DCR registers base/len!\n", np);
4449 		of_node_put(np);
4450 		iounmap(i2o_reg);
4451 		return -ENODEV;
4452 	}
4453 
4454 	i2o_dcr_host = dcr_map(np, dcr_base, dcr_len);
4455 	if (!DCR_MAP_OK(i2o_dcr_host)) {
4456 		pr_err("%pOF: failed to map DCRs!\n", np);
4457 		of_node_put(np);
4458 		iounmap(i2o_reg);
4459 		return -ENODEV;
4460 	}
4461 	of_node_put(np);
4462 
4463 	/* Provide memory regions for DMA's FIFOs: I2O, DMA0 and DMA1 share
4464 	 * the base address of FIFO memory space.
4465 	 * Actually we need twice more physical memory than programmed in the
4466 	 * <fsiz> register (because there are two FIFOs for each DMA: CP and CS)
4467 	 */
4468 	ppc440spe_dma_fifo_buf = kmalloc((DMA0_FIFO_SIZE + DMA1_FIFO_SIZE) << 1,
4469 					 GFP_KERNEL);
4470 	if (!ppc440spe_dma_fifo_buf) {
4471 		pr_err("%s: DMA FIFO buffer allocation failed.\n", __func__);
4472 		iounmap(i2o_reg);
4473 		dcr_unmap(i2o_dcr_host, dcr_len);
4474 		return -ENOMEM;
4475 	}
4476 
4477 	/*
4478 	 * Configure h/w
4479 	 */
4480 	/* Reset I2O/DMA */
4481 	mtdcri(SDR0, DCRN_SDR0_SRST, DCRN_SDR0_SRST_I2ODMA);
4482 	mtdcri(SDR0, DCRN_SDR0_SRST, 0);
4483 
4484 	/* Setup the base address of mmaped registers */
4485 	dcr_write(i2o_dcr_host, DCRN_I2O0_IBAH, (u32)(i2o_res.start >> 32));
4486 	dcr_write(i2o_dcr_host, DCRN_I2O0_IBAL, (u32)(i2o_res.start) |
4487 						I2O_REG_ENABLE);
4488 	dcr_unmap(i2o_dcr_host, dcr_len);
4489 
4490 	/* Setup FIFO memory space base address */
4491 	iowrite32(0, &i2o_reg->ifbah);
4492 	iowrite32(((u32)__pa(ppc440spe_dma_fifo_buf)), &i2o_reg->ifbal);
4493 
4494 	/* set zero FIFO size for I2O, so the whole
4495 	 * ppc440spe_dma_fifo_buf is used by DMAs.
4496 	 * DMAx_FIFOs will be configured while probe.
4497 	 */
4498 	iowrite32(0, &i2o_reg->ifsiz);
4499 	iounmap(i2o_reg);
4500 
4501 	/* To prepare WXOR/RXOR functionality we need access to
4502 	 * Memory Queue Module DCRs (finally it will be enabled
4503 	 * via /sys interface of the ppc440spe ADMA driver).
4504 	 */
4505 	np = of_find_compatible_node(NULL, NULL, "ibm,mq-440spe");
4506 	if (!np) {
4507 		pr_err("%s: can't find MQ device tree node\n",
4508 			__func__);
4509 		ret = -ENODEV;
4510 		goto out_free;
4511 	}
4512 
4513 	/* Get MQ DCRs base */
4514 	dcr_base = dcr_resource_start(np, 0);
4515 	dcr_len = dcr_resource_len(np, 0);
4516 	if (!dcr_base && !dcr_len) {
4517 		pr_err("%pOF: can't get DCR registers base/len!\n", np);
4518 		ret = -ENODEV;
4519 		goto out_mq;
4520 	}
4521 
4522 	ppc440spe_mq_dcr_host = dcr_map(np, dcr_base, dcr_len);
4523 	if (!DCR_MAP_OK(ppc440spe_mq_dcr_host)) {
4524 		pr_err("%pOF: failed to map DCRs!\n", np);
4525 		ret = -ENODEV;
4526 		goto out_mq;
4527 	}
4528 	of_node_put(np);
4529 	ppc440spe_mq_dcr_len = dcr_len;
4530 
4531 	/* Set HB alias */
4532 	dcr_write(ppc440spe_mq_dcr_host, DCRN_MQ0_BAUH, DMA_CUED_XOR_HB);
4533 
4534 	/* Set:
4535 	 * - LL transaction passing limit to 1;
4536 	 * - Memory controller cycle limit to 1;
4537 	 * - Galois Polynomial to 0x14d (default)
4538 	 */
4539 	dcr_write(ppc440spe_mq_dcr_host, DCRN_MQ0_CFBHL,
4540 		  (1 << MQ0_CFBHL_TPLM) | (1 << MQ0_CFBHL_HBCL) |
4541 		  (PPC440SPE_DEFAULT_POLY << MQ0_CFBHL_POLY));
4542 
4543 	atomic_set(&ppc440spe_adma_err_irq_ref, 0);
4544 	for (i = 0; i < PPC440SPE_ADMA_ENGINES_NUM; i++)
4545 		ppc440spe_adma_devices[i] = -1;
4546 
4547 	return 0;
4548 
4549 out_mq:
4550 	of_node_put(np);
4551 out_free:
4552 	kfree(ppc440spe_dma_fifo_buf);
4553 	return ret;
4554 }
4555 
4556 static const struct of_device_id ppc440spe_adma_of_match[] = {
4557 	{ .compatible	= "ibm,dma-440spe", },
4558 	{ .compatible	= "amcc,xor-accelerator", },
4559 	{},
4560 };
4561 MODULE_DEVICE_TABLE(of, ppc440spe_adma_of_match);
4562 
4563 static struct platform_driver ppc440spe_adma_driver = {
4564 	.probe = ppc440spe_adma_probe,
4565 	.remove = ppc440spe_adma_remove,
4566 	.driver = {
4567 		.name = "PPC440SP(E)-ADMA",
4568 		.of_match_table = ppc440spe_adma_of_match,
4569 	},
4570 };
4571 
4572 static __init int ppc440spe_adma_init(void)
4573 {
4574 	int ret;
4575 
4576 	ret = ppc440spe_configure_raid_devices();
4577 	if (ret)
4578 		return ret;
4579 
4580 	ret = platform_driver_register(&ppc440spe_adma_driver);
4581 	if (ret) {
4582 		pr_err("%s: failed to register platform driver\n",
4583 			__func__);
4584 		goto out_reg;
4585 	}
4586 
4587 	/* Initialization status */
4588 	ret = driver_create_file(&ppc440spe_adma_driver.driver,
4589 				 &driver_attr_devices);
4590 	if (ret)
4591 		goto out_dev;
4592 
4593 	/* RAID-6 h/w enable entry */
4594 	ret = driver_create_file(&ppc440spe_adma_driver.driver,
4595 				 &driver_attr_enable);
4596 	if (ret)
4597 		goto out_en;
4598 
4599 	/* GF polynomial to use */
4600 	ret = driver_create_file(&ppc440spe_adma_driver.driver,
4601 				 &driver_attr_poly);
4602 	if (!ret)
4603 		return ret;
4604 
4605 	driver_remove_file(&ppc440spe_adma_driver.driver,
4606 			   &driver_attr_enable);
4607 out_en:
4608 	driver_remove_file(&ppc440spe_adma_driver.driver,
4609 			   &driver_attr_devices);
4610 out_dev:
4611 	/* User will not be able to enable h/w RAID-6 */
4612 	pr_err("%s: failed to create RAID-6 driver interface\n",
4613 		__func__);
4614 	platform_driver_unregister(&ppc440spe_adma_driver);
4615 out_reg:
4616 	dcr_unmap(ppc440spe_mq_dcr_host, ppc440spe_mq_dcr_len);
4617 	kfree(ppc440spe_dma_fifo_buf);
4618 	return ret;
4619 }
4620 
4621 static void __exit ppc440spe_adma_exit(void)
4622 {
4623 	driver_remove_file(&ppc440spe_adma_driver.driver,
4624 			   &driver_attr_poly);
4625 	driver_remove_file(&ppc440spe_adma_driver.driver,
4626 			   &driver_attr_enable);
4627 	driver_remove_file(&ppc440spe_adma_driver.driver,
4628 			   &driver_attr_devices);
4629 	platform_driver_unregister(&ppc440spe_adma_driver);
4630 	dcr_unmap(ppc440spe_mq_dcr_host, ppc440spe_mq_dcr_len);
4631 	kfree(ppc440spe_dma_fifo_buf);
4632 }
4633 
4634 arch_initcall(ppc440spe_adma_init);
4635 module_exit(ppc440spe_adma_exit);
4636 
4637 MODULE_AUTHOR("Yuri Tikhonov <yur@emcraft.com>");
4638 MODULE_DESCRIPTION("PPC440SPE ADMA Engine Driver");
4639 MODULE_LICENSE("GPL");
4640