xref: /openbmc/linux/drivers/dma/ppc4xx/adma.c (revision 3a83e4e6)
1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3  * Copyright (C) 2006-2009 DENX Software Engineering.
4  *
5  * Author: Yuri Tikhonov <yur@emcraft.com>
6  *
7  * Further porting to arch/powerpc by
8  * 	Anatolij Gustschin <agust@denx.de>
9  */
10 
11 /*
12  * This driver supports the asynchrounous DMA copy and RAID engines available
13  * on the AMCC PPC440SPe Processors.
14  * Based on the Intel Xscale(R) family of I/O Processors (IOP 32x, 33x, 134x)
15  * ADMA driver written by D.Williams.
16  */
17 
18 #include <linux/init.h>
19 #include <linux/module.h>
20 #include <linux/async_tx.h>
21 #include <linux/delay.h>
22 #include <linux/dma-mapping.h>
23 #include <linux/spinlock.h>
24 #include <linux/interrupt.h>
25 #include <linux/slab.h>
26 #include <linux/uaccess.h>
27 #include <linux/proc_fs.h>
28 #include <linux/of.h>
29 #include <linux/of_address.h>
30 #include <linux/of_irq.h>
31 #include <linux/of_platform.h>
32 #include <asm/dcr.h>
33 #include <asm/dcr-regs.h>
34 #include "adma.h"
35 #include "../dmaengine.h"
36 
37 enum ppc_adma_init_code {
38 	PPC_ADMA_INIT_OK = 0,
39 	PPC_ADMA_INIT_MEMRES,
40 	PPC_ADMA_INIT_MEMREG,
41 	PPC_ADMA_INIT_ALLOC,
42 	PPC_ADMA_INIT_COHERENT,
43 	PPC_ADMA_INIT_CHANNEL,
44 	PPC_ADMA_INIT_IRQ1,
45 	PPC_ADMA_INIT_IRQ2,
46 	PPC_ADMA_INIT_REGISTER
47 };
48 
49 static char *ppc_adma_errors[] = {
50 	[PPC_ADMA_INIT_OK] = "ok",
51 	[PPC_ADMA_INIT_MEMRES] = "failed to get memory resource",
52 	[PPC_ADMA_INIT_MEMREG] = "failed to request memory region",
53 	[PPC_ADMA_INIT_ALLOC] = "failed to allocate memory for adev "
54 				"structure",
55 	[PPC_ADMA_INIT_COHERENT] = "failed to allocate coherent memory for "
56 				   "hardware descriptors",
57 	[PPC_ADMA_INIT_CHANNEL] = "failed to allocate memory for channel",
58 	[PPC_ADMA_INIT_IRQ1] = "failed to request first irq",
59 	[PPC_ADMA_INIT_IRQ2] = "failed to request second irq",
60 	[PPC_ADMA_INIT_REGISTER] = "failed to register dma async device",
61 };
62 
63 static enum ppc_adma_init_code
64 ppc440spe_adma_devices[PPC440SPE_ADMA_ENGINES_NUM];
65 
66 struct ppc_dma_chan_ref {
67 	struct dma_chan *chan;
68 	struct list_head node;
69 };
70 
71 /* The list of channels exported by ppc440spe ADMA */
72 struct list_head
73 ppc440spe_adma_chan_list = LIST_HEAD_INIT(ppc440spe_adma_chan_list);
74 
75 /* This flag is set when want to refetch the xor chain in the interrupt
76  * handler
77  */
78 static u32 do_xor_refetch;
79 
80 /* Pointer to DMA0, DMA1 CP/CS FIFO */
81 static void *ppc440spe_dma_fifo_buf;
82 
83 /* Pointers to last submitted to DMA0, DMA1 CDBs */
84 static struct ppc440spe_adma_desc_slot *chan_last_sub[3];
85 static struct ppc440spe_adma_desc_slot *chan_first_cdb[3];
86 
87 /* Pointer to last linked and submitted xor CB */
88 static struct ppc440spe_adma_desc_slot *xor_last_linked;
89 static struct ppc440spe_adma_desc_slot *xor_last_submit;
90 
91 /* This array is used in data-check operations for storing a pattern */
92 static char ppc440spe_qword[16];
93 
94 static atomic_t ppc440spe_adma_err_irq_ref;
95 static dcr_host_t ppc440spe_mq_dcr_host;
96 static unsigned int ppc440spe_mq_dcr_len;
97 
98 /* Since RXOR operations use the common register (MQ0_CF2H) for setting-up
99  * the block size in transactions, then we do not allow to activate more than
100  * only one RXOR transactions simultaneously. So use this var to store
101  * the information about is RXOR currently active (PPC440SPE_RXOR_RUN bit is
102  * set) or not (PPC440SPE_RXOR_RUN is clear).
103  */
104 static unsigned long ppc440spe_rxor_state;
105 
106 /* These are used in enable & check routines
107  */
108 static u32 ppc440spe_r6_enabled;
109 static struct ppc440spe_adma_chan *ppc440spe_r6_tchan;
110 static struct completion ppc440spe_r6_test_comp;
111 
112 static int ppc440spe_adma_dma2rxor_prep_src(
113 		struct ppc440spe_adma_desc_slot *desc,
114 		struct ppc440spe_rxor *cursor, int index,
115 		int src_cnt, u32 addr);
116 static void ppc440spe_adma_dma2rxor_set_src(
117 		struct ppc440spe_adma_desc_slot *desc,
118 		int index, dma_addr_t addr);
119 static void ppc440spe_adma_dma2rxor_set_mult(
120 		struct ppc440spe_adma_desc_slot *desc,
121 		int index, u8 mult);
122 
123 #ifdef ADMA_LL_DEBUG
124 #define ADMA_LL_DBG(x) ({ if (1) x; 0; })
125 #else
126 #define ADMA_LL_DBG(x) ({ if (0) x; 0; })
127 #endif
128 
129 static void print_cb(struct ppc440spe_adma_chan *chan, void *block)
130 {
131 	struct dma_cdb *cdb;
132 	struct xor_cb *cb;
133 	int i;
134 
135 	switch (chan->device->id) {
136 	case 0:
137 	case 1:
138 		cdb = block;
139 
140 		pr_debug("CDB at %p [%d]:\n"
141 			"\t attr 0x%02x opc 0x%02x cnt 0x%08x\n"
142 			"\t sg1u 0x%08x sg1l 0x%08x\n"
143 			"\t sg2u 0x%08x sg2l 0x%08x\n"
144 			"\t sg3u 0x%08x sg3l 0x%08x\n",
145 			cdb, chan->device->id,
146 			cdb->attr, cdb->opc, le32_to_cpu(cdb->cnt),
147 			le32_to_cpu(cdb->sg1u), le32_to_cpu(cdb->sg1l),
148 			le32_to_cpu(cdb->sg2u), le32_to_cpu(cdb->sg2l),
149 			le32_to_cpu(cdb->sg3u), le32_to_cpu(cdb->sg3l)
150 		);
151 		break;
152 	case 2:
153 		cb = block;
154 
155 		pr_debug("CB at %p [%d]:\n"
156 			"\t cbc 0x%08x cbbc 0x%08x cbs 0x%08x\n"
157 			"\t cbtah 0x%08x cbtal 0x%08x\n"
158 			"\t cblah 0x%08x cblal 0x%08x\n",
159 			cb, chan->device->id,
160 			cb->cbc, cb->cbbc, cb->cbs,
161 			cb->cbtah, cb->cbtal,
162 			cb->cblah, cb->cblal);
163 		for (i = 0; i < 16; i++) {
164 			if (i && !cb->ops[i].h && !cb->ops[i].l)
165 				continue;
166 			pr_debug("\t ops[%2d]: h 0x%08x l 0x%08x\n",
167 				i, cb->ops[i].h, cb->ops[i].l);
168 		}
169 		break;
170 	}
171 }
172 
173 static void print_cb_list(struct ppc440spe_adma_chan *chan,
174 			  struct ppc440spe_adma_desc_slot *iter)
175 {
176 	for (; iter; iter = iter->hw_next)
177 		print_cb(chan, iter->hw_desc);
178 }
179 
180 static void prep_dma_xor_dbg(int id, dma_addr_t dst, dma_addr_t *src,
181 			     unsigned int src_cnt)
182 {
183 	int i;
184 
185 	pr_debug("\n%s(%d):\nsrc: ", __func__, id);
186 	for (i = 0; i < src_cnt; i++)
187 		pr_debug("\t0x%016llx ", src[i]);
188 	pr_debug("dst:\n\t0x%016llx\n", dst);
189 }
190 
191 static void prep_dma_pq_dbg(int id, dma_addr_t *dst, dma_addr_t *src,
192 			    unsigned int src_cnt)
193 {
194 	int i;
195 
196 	pr_debug("\n%s(%d):\nsrc: ", __func__, id);
197 	for (i = 0; i < src_cnt; i++)
198 		pr_debug("\t0x%016llx ", src[i]);
199 	pr_debug("dst: ");
200 	for (i = 0; i < 2; i++)
201 		pr_debug("\t0x%016llx ", dst[i]);
202 }
203 
204 static void prep_dma_pqzero_sum_dbg(int id, dma_addr_t *src,
205 				    unsigned int src_cnt,
206 				    const unsigned char *scf)
207 {
208 	int i;
209 
210 	pr_debug("\n%s(%d):\nsrc(coef): ", __func__, id);
211 	if (scf) {
212 		for (i = 0; i < src_cnt; i++)
213 			pr_debug("\t0x%016llx(0x%02x) ", src[i], scf[i]);
214 	} else {
215 		for (i = 0; i < src_cnt; i++)
216 			pr_debug("\t0x%016llx(no) ", src[i]);
217 	}
218 
219 	pr_debug("dst: ");
220 	for (i = 0; i < 2; i++)
221 		pr_debug("\t0x%016llx ", src[src_cnt + i]);
222 }
223 
224 /******************************************************************************
225  * Command (Descriptor) Blocks low-level routines
226  ******************************************************************************/
227 /**
228  * ppc440spe_desc_init_interrupt - initialize the descriptor for INTERRUPT
229  * pseudo operation
230  */
231 static void ppc440spe_desc_init_interrupt(struct ppc440spe_adma_desc_slot *desc,
232 					  struct ppc440spe_adma_chan *chan)
233 {
234 	struct xor_cb *p;
235 
236 	switch (chan->device->id) {
237 	case PPC440SPE_XOR_ID:
238 		p = desc->hw_desc;
239 		memset(desc->hw_desc, 0, sizeof(struct xor_cb));
240 		/* NOP with Command Block Complete Enable */
241 		p->cbc = XOR_CBCR_CBCE_BIT;
242 		break;
243 	case PPC440SPE_DMA0_ID:
244 	case PPC440SPE_DMA1_ID:
245 		memset(desc->hw_desc, 0, sizeof(struct dma_cdb));
246 		/* NOP with interrupt */
247 		set_bit(PPC440SPE_DESC_INT, &desc->flags);
248 		break;
249 	default:
250 		printk(KERN_ERR "Unsupported id %d in %s\n", chan->device->id,
251 				__func__);
252 		break;
253 	}
254 }
255 
256 /**
257  * ppc440spe_desc_init_null_xor - initialize the descriptor for NULL XOR
258  * pseudo operation
259  */
260 static void ppc440spe_desc_init_null_xor(struct ppc440spe_adma_desc_slot *desc)
261 {
262 	memset(desc->hw_desc, 0, sizeof(struct xor_cb));
263 	desc->hw_next = NULL;
264 	desc->src_cnt = 0;
265 	desc->dst_cnt = 1;
266 }
267 
268 /**
269  * ppc440spe_desc_init_xor - initialize the descriptor for XOR operation
270  */
271 static void ppc440spe_desc_init_xor(struct ppc440spe_adma_desc_slot *desc,
272 					 int src_cnt, unsigned long flags)
273 {
274 	struct xor_cb *hw_desc = desc->hw_desc;
275 
276 	memset(desc->hw_desc, 0, sizeof(struct xor_cb));
277 	desc->hw_next = NULL;
278 	desc->src_cnt = src_cnt;
279 	desc->dst_cnt = 1;
280 
281 	hw_desc->cbc = XOR_CBCR_TGT_BIT | src_cnt;
282 	if (flags & DMA_PREP_INTERRUPT)
283 		/* Enable interrupt on completion */
284 		hw_desc->cbc |= XOR_CBCR_CBCE_BIT;
285 }
286 
287 /**
288  * ppc440spe_desc_init_dma2pq - initialize the descriptor for PQ
289  * operation in DMA2 controller
290  */
291 static void ppc440spe_desc_init_dma2pq(struct ppc440spe_adma_desc_slot *desc,
292 		int dst_cnt, int src_cnt, unsigned long flags)
293 {
294 	struct xor_cb *hw_desc = desc->hw_desc;
295 
296 	memset(desc->hw_desc, 0, sizeof(struct xor_cb));
297 	desc->hw_next = NULL;
298 	desc->src_cnt = src_cnt;
299 	desc->dst_cnt = dst_cnt;
300 	memset(desc->reverse_flags, 0, sizeof(desc->reverse_flags));
301 	desc->descs_per_op = 0;
302 
303 	hw_desc->cbc = XOR_CBCR_TGT_BIT;
304 	if (flags & DMA_PREP_INTERRUPT)
305 		/* Enable interrupt on completion */
306 		hw_desc->cbc |= XOR_CBCR_CBCE_BIT;
307 }
308 
309 #define DMA_CTRL_FLAGS_LAST	DMA_PREP_FENCE
310 #define DMA_PREP_ZERO_P		(DMA_CTRL_FLAGS_LAST << 1)
311 #define DMA_PREP_ZERO_Q		(DMA_PREP_ZERO_P << 1)
312 
313 /**
314  * ppc440spe_desc_init_dma01pq - initialize the descriptors for PQ operation
315  * with DMA0/1
316  */
317 static void ppc440spe_desc_init_dma01pq(struct ppc440spe_adma_desc_slot *desc,
318 				int dst_cnt, int src_cnt, unsigned long flags,
319 				unsigned long op)
320 {
321 	struct dma_cdb *hw_desc;
322 	struct ppc440spe_adma_desc_slot *iter;
323 	u8 dopc;
324 
325 	/* Common initialization of a PQ descriptors chain */
326 	set_bits(op, &desc->flags);
327 	desc->src_cnt = src_cnt;
328 	desc->dst_cnt = dst_cnt;
329 
330 	/* WXOR MULTICAST if both P and Q are being computed
331 	 * MV_SG1_SG2 if Q only
332 	 */
333 	dopc = (desc->dst_cnt == DMA_DEST_MAX_NUM) ?
334 		DMA_CDB_OPC_MULTICAST : DMA_CDB_OPC_MV_SG1_SG2;
335 
336 	list_for_each_entry(iter, &desc->group_list, chain_node) {
337 		hw_desc = iter->hw_desc;
338 		memset(iter->hw_desc, 0, sizeof(struct dma_cdb));
339 
340 		if (likely(!list_is_last(&iter->chain_node,
341 				&desc->group_list))) {
342 			/* set 'next' pointer */
343 			iter->hw_next = list_entry(iter->chain_node.next,
344 				struct ppc440spe_adma_desc_slot, chain_node);
345 			clear_bit(PPC440SPE_DESC_INT, &iter->flags);
346 		} else {
347 			/* this is the last descriptor.
348 			 * this slot will be pasted from ADMA level
349 			 * each time it wants to configure parameters
350 			 * of the transaction (src, dst, ...)
351 			 */
352 			iter->hw_next = NULL;
353 			if (flags & DMA_PREP_INTERRUPT)
354 				set_bit(PPC440SPE_DESC_INT, &iter->flags);
355 			else
356 				clear_bit(PPC440SPE_DESC_INT, &iter->flags);
357 		}
358 	}
359 
360 	/* Set OPS depending on WXOR/RXOR type of operation */
361 	if (!test_bit(PPC440SPE_DESC_RXOR, &desc->flags)) {
362 		/* This is a WXOR only chain:
363 		 * - first descriptors are for zeroing destinations
364 		 *   if PPC440SPE_ZERO_P/Q set;
365 		 * - descriptors remained are for GF-XOR operations.
366 		 */
367 		iter = list_first_entry(&desc->group_list,
368 					struct ppc440spe_adma_desc_slot,
369 					chain_node);
370 
371 		if (test_bit(PPC440SPE_ZERO_P, &desc->flags)) {
372 			hw_desc = iter->hw_desc;
373 			hw_desc->opc = DMA_CDB_OPC_MV_SG1_SG2;
374 			iter = list_first_entry(&iter->chain_node,
375 					struct ppc440spe_adma_desc_slot,
376 					chain_node);
377 		}
378 
379 		if (test_bit(PPC440SPE_ZERO_Q, &desc->flags)) {
380 			hw_desc = iter->hw_desc;
381 			hw_desc->opc = DMA_CDB_OPC_MV_SG1_SG2;
382 			iter = list_first_entry(&iter->chain_node,
383 					struct ppc440spe_adma_desc_slot,
384 					chain_node);
385 		}
386 
387 		list_for_each_entry_from(iter, &desc->group_list, chain_node) {
388 			hw_desc = iter->hw_desc;
389 			hw_desc->opc = dopc;
390 		}
391 	} else {
392 		/* This is either RXOR-only or mixed RXOR/WXOR */
393 
394 		/* The first 1 or 2 slots in chain are always RXOR,
395 		 * if need to calculate P & Q, then there are two
396 		 * RXOR slots; if only P or only Q, then there is one
397 		 */
398 		iter = list_first_entry(&desc->group_list,
399 					struct ppc440spe_adma_desc_slot,
400 					chain_node);
401 		hw_desc = iter->hw_desc;
402 		hw_desc->opc = DMA_CDB_OPC_MV_SG1_SG2;
403 
404 		if (desc->dst_cnt == DMA_DEST_MAX_NUM) {
405 			iter = list_first_entry(&iter->chain_node,
406 						struct ppc440spe_adma_desc_slot,
407 						chain_node);
408 			hw_desc = iter->hw_desc;
409 			hw_desc->opc = DMA_CDB_OPC_MV_SG1_SG2;
410 		}
411 
412 		/* The remaining descs (if any) are WXORs */
413 		if (test_bit(PPC440SPE_DESC_WXOR, &desc->flags)) {
414 			iter = list_first_entry(&iter->chain_node,
415 						struct ppc440spe_adma_desc_slot,
416 						chain_node);
417 			list_for_each_entry_from(iter, &desc->group_list,
418 						chain_node) {
419 				hw_desc = iter->hw_desc;
420 				hw_desc->opc = dopc;
421 			}
422 		}
423 	}
424 }
425 
426 /**
427  * ppc440spe_desc_init_dma01pqzero_sum - initialize the descriptor
428  * for PQ_ZERO_SUM operation
429  */
430 static void ppc440spe_desc_init_dma01pqzero_sum(
431 				struct ppc440spe_adma_desc_slot *desc,
432 				int dst_cnt, int src_cnt)
433 {
434 	struct dma_cdb *hw_desc;
435 	struct ppc440spe_adma_desc_slot *iter;
436 	int i = 0;
437 	u8 dopc = (dst_cnt == 2) ? DMA_CDB_OPC_MULTICAST :
438 				   DMA_CDB_OPC_MV_SG1_SG2;
439 	/*
440 	 * Initialize starting from 2nd or 3rd descriptor dependent
441 	 * on dst_cnt. First one or two slots are for cloning P
442 	 * and/or Q to chan->pdest and/or chan->qdest as we have
443 	 * to preserve original P/Q.
444 	 */
445 	iter = list_first_entry(&desc->group_list,
446 				struct ppc440spe_adma_desc_slot, chain_node);
447 	iter = list_entry(iter->chain_node.next,
448 			  struct ppc440spe_adma_desc_slot, chain_node);
449 
450 	if (dst_cnt > 1) {
451 		iter = list_entry(iter->chain_node.next,
452 				  struct ppc440spe_adma_desc_slot, chain_node);
453 	}
454 	/* initialize each source descriptor in chain */
455 	list_for_each_entry_from(iter, &desc->group_list, chain_node) {
456 		hw_desc = iter->hw_desc;
457 		memset(iter->hw_desc, 0, sizeof(struct dma_cdb));
458 		iter->src_cnt = 0;
459 		iter->dst_cnt = 0;
460 
461 		/* This is a ZERO_SUM operation:
462 		 * - <src_cnt> descriptors starting from 2nd or 3rd
463 		 *   descriptor are for GF-XOR operations;
464 		 * - remaining <dst_cnt> descriptors are for checking the result
465 		 */
466 		if (i++ < src_cnt)
467 			/* MV_SG1_SG2 if only Q is being verified
468 			 * MULTICAST if both P and Q are being verified
469 			 */
470 			hw_desc->opc = dopc;
471 		else
472 			/* DMA_CDB_OPC_DCHECK128 operation */
473 			hw_desc->opc = DMA_CDB_OPC_DCHECK128;
474 
475 		if (likely(!list_is_last(&iter->chain_node,
476 					 &desc->group_list))) {
477 			/* set 'next' pointer */
478 			iter->hw_next = list_entry(iter->chain_node.next,
479 						struct ppc440spe_adma_desc_slot,
480 						chain_node);
481 		} else {
482 			/* this is the last descriptor.
483 			 * this slot will be pasted from ADMA level
484 			 * each time it wants to configure parameters
485 			 * of the transaction (src, dst, ...)
486 			 */
487 			iter->hw_next = NULL;
488 			/* always enable interrupt generation since we get
489 			 * the status of pqzero from the handler
490 			 */
491 			set_bit(PPC440SPE_DESC_INT, &iter->flags);
492 		}
493 	}
494 	desc->src_cnt = src_cnt;
495 	desc->dst_cnt = dst_cnt;
496 }
497 
498 /**
499  * ppc440spe_desc_init_memcpy - initialize the descriptor for MEMCPY operation
500  */
501 static void ppc440spe_desc_init_memcpy(struct ppc440spe_adma_desc_slot *desc,
502 					unsigned long flags)
503 {
504 	struct dma_cdb *hw_desc = desc->hw_desc;
505 
506 	memset(desc->hw_desc, 0, sizeof(struct dma_cdb));
507 	desc->hw_next = NULL;
508 	desc->src_cnt = 1;
509 	desc->dst_cnt = 1;
510 
511 	if (flags & DMA_PREP_INTERRUPT)
512 		set_bit(PPC440SPE_DESC_INT, &desc->flags);
513 	else
514 		clear_bit(PPC440SPE_DESC_INT, &desc->flags);
515 
516 	hw_desc->opc = DMA_CDB_OPC_MV_SG1_SG2;
517 }
518 
519 /**
520  * ppc440spe_desc_set_src_addr - set source address into the descriptor
521  */
522 static void ppc440spe_desc_set_src_addr(struct ppc440spe_adma_desc_slot *desc,
523 					struct ppc440spe_adma_chan *chan,
524 					int src_idx, dma_addr_t addrh,
525 					dma_addr_t addrl)
526 {
527 	struct dma_cdb *dma_hw_desc;
528 	struct xor_cb *xor_hw_desc;
529 	phys_addr_t addr64, tmplow, tmphi;
530 
531 	switch (chan->device->id) {
532 	case PPC440SPE_DMA0_ID:
533 	case PPC440SPE_DMA1_ID:
534 		if (!addrh) {
535 			addr64 = addrl;
536 			tmphi = (addr64 >> 32);
537 			tmplow = (addr64 & 0xFFFFFFFF);
538 		} else {
539 			tmphi = addrh;
540 			tmplow = addrl;
541 		}
542 		dma_hw_desc = desc->hw_desc;
543 		dma_hw_desc->sg1l = cpu_to_le32((u32)tmplow);
544 		dma_hw_desc->sg1u |= cpu_to_le32((u32)tmphi);
545 		break;
546 	case PPC440SPE_XOR_ID:
547 		xor_hw_desc = desc->hw_desc;
548 		xor_hw_desc->ops[src_idx].l = addrl;
549 		xor_hw_desc->ops[src_idx].h |= addrh;
550 		break;
551 	}
552 }
553 
554 /**
555  * ppc440spe_desc_set_src_mult - set source address mult into the descriptor
556  */
557 static void ppc440spe_desc_set_src_mult(struct ppc440spe_adma_desc_slot *desc,
558 			struct ppc440spe_adma_chan *chan, u32 mult_index,
559 			int sg_index, unsigned char mult_value)
560 {
561 	struct dma_cdb *dma_hw_desc;
562 	struct xor_cb *xor_hw_desc;
563 	u32 *psgu;
564 
565 	switch (chan->device->id) {
566 	case PPC440SPE_DMA0_ID:
567 	case PPC440SPE_DMA1_ID:
568 		dma_hw_desc = desc->hw_desc;
569 
570 		switch (sg_index) {
571 		/* for RXOR operations set multiplier
572 		 * into source cued address
573 		 */
574 		case DMA_CDB_SG_SRC:
575 			psgu = &dma_hw_desc->sg1u;
576 			break;
577 		/* for WXOR operations set multiplier
578 		 * into destination cued address(es)
579 		 */
580 		case DMA_CDB_SG_DST1:
581 			psgu = &dma_hw_desc->sg2u;
582 			break;
583 		case DMA_CDB_SG_DST2:
584 			psgu = &dma_hw_desc->sg3u;
585 			break;
586 		default:
587 			BUG();
588 		}
589 
590 		*psgu |= cpu_to_le32(mult_value << mult_index);
591 		break;
592 	case PPC440SPE_XOR_ID:
593 		xor_hw_desc = desc->hw_desc;
594 		break;
595 	default:
596 		BUG();
597 	}
598 }
599 
600 /**
601  * ppc440spe_desc_set_dest_addr - set destination address into the descriptor
602  */
603 static void ppc440spe_desc_set_dest_addr(struct ppc440spe_adma_desc_slot *desc,
604 				struct ppc440spe_adma_chan *chan,
605 				dma_addr_t addrh, dma_addr_t addrl,
606 				u32 dst_idx)
607 {
608 	struct dma_cdb *dma_hw_desc;
609 	struct xor_cb *xor_hw_desc;
610 	phys_addr_t addr64, tmphi, tmplow;
611 	u32 *psgu, *psgl;
612 
613 	switch (chan->device->id) {
614 	case PPC440SPE_DMA0_ID:
615 	case PPC440SPE_DMA1_ID:
616 		if (!addrh) {
617 			addr64 = addrl;
618 			tmphi = (addr64 >> 32);
619 			tmplow = (addr64 & 0xFFFFFFFF);
620 		} else {
621 			tmphi = addrh;
622 			tmplow = addrl;
623 		}
624 		dma_hw_desc = desc->hw_desc;
625 
626 		psgu = dst_idx ? &dma_hw_desc->sg3u : &dma_hw_desc->sg2u;
627 		psgl = dst_idx ? &dma_hw_desc->sg3l : &dma_hw_desc->sg2l;
628 
629 		*psgl = cpu_to_le32((u32)tmplow);
630 		*psgu |= cpu_to_le32((u32)tmphi);
631 		break;
632 	case PPC440SPE_XOR_ID:
633 		xor_hw_desc = desc->hw_desc;
634 		xor_hw_desc->cbtal = addrl;
635 		xor_hw_desc->cbtah |= addrh;
636 		break;
637 	}
638 }
639 
640 /**
641  * ppc440spe_desc_set_byte_count - set number of data bytes involved
642  * into the operation
643  */
644 static void ppc440spe_desc_set_byte_count(struct ppc440spe_adma_desc_slot *desc,
645 				struct ppc440spe_adma_chan *chan,
646 				u32 byte_count)
647 {
648 	struct dma_cdb *dma_hw_desc;
649 	struct xor_cb *xor_hw_desc;
650 
651 	switch (chan->device->id) {
652 	case PPC440SPE_DMA0_ID:
653 	case PPC440SPE_DMA1_ID:
654 		dma_hw_desc = desc->hw_desc;
655 		dma_hw_desc->cnt = cpu_to_le32(byte_count);
656 		break;
657 	case PPC440SPE_XOR_ID:
658 		xor_hw_desc = desc->hw_desc;
659 		xor_hw_desc->cbbc = byte_count;
660 		break;
661 	}
662 }
663 
664 /**
665  * ppc440spe_desc_set_rxor_block_size - set RXOR block size
666  */
667 static inline void ppc440spe_desc_set_rxor_block_size(u32 byte_count)
668 {
669 	/* assume that byte_count is aligned on the 512-boundary;
670 	 * thus write it directly to the register (bits 23:31 are
671 	 * reserved there).
672 	 */
673 	dcr_write(ppc440spe_mq_dcr_host, DCRN_MQ0_CF2H, byte_count);
674 }
675 
676 /**
677  * ppc440spe_desc_set_dcheck - set CHECK pattern
678  */
679 static void ppc440spe_desc_set_dcheck(struct ppc440spe_adma_desc_slot *desc,
680 				struct ppc440spe_adma_chan *chan, u8 *qword)
681 {
682 	struct dma_cdb *dma_hw_desc;
683 
684 	switch (chan->device->id) {
685 	case PPC440SPE_DMA0_ID:
686 	case PPC440SPE_DMA1_ID:
687 		dma_hw_desc = desc->hw_desc;
688 		iowrite32(qword[0], &dma_hw_desc->sg3l);
689 		iowrite32(qword[4], &dma_hw_desc->sg3u);
690 		iowrite32(qword[8], &dma_hw_desc->sg2l);
691 		iowrite32(qword[12], &dma_hw_desc->sg2u);
692 		break;
693 	default:
694 		BUG();
695 	}
696 }
697 
698 /**
699  * ppc440spe_xor_set_link - set link address in xor CB
700  */
701 static void ppc440spe_xor_set_link(struct ppc440spe_adma_desc_slot *prev_desc,
702 				struct ppc440spe_adma_desc_slot *next_desc)
703 {
704 	struct xor_cb *xor_hw_desc = prev_desc->hw_desc;
705 
706 	if (unlikely(!next_desc || !(next_desc->phys))) {
707 		printk(KERN_ERR "%s: next_desc=0x%p; next_desc->phys=0x%llx\n",
708 			__func__, next_desc,
709 			next_desc ? next_desc->phys : 0);
710 		BUG();
711 	}
712 
713 	xor_hw_desc->cbs = 0;
714 	xor_hw_desc->cblal = next_desc->phys;
715 	xor_hw_desc->cblah = 0;
716 	xor_hw_desc->cbc |= XOR_CBCR_LNK_BIT;
717 }
718 
719 /**
720  * ppc440spe_desc_set_link - set the address of descriptor following this
721  * descriptor in chain
722  */
723 static void ppc440spe_desc_set_link(struct ppc440spe_adma_chan *chan,
724 				struct ppc440spe_adma_desc_slot *prev_desc,
725 				struct ppc440spe_adma_desc_slot *next_desc)
726 {
727 	unsigned long flags;
728 	struct ppc440spe_adma_desc_slot *tail = next_desc;
729 
730 	if (unlikely(!prev_desc || !next_desc ||
731 		(prev_desc->hw_next && prev_desc->hw_next != next_desc))) {
732 		/* If previous next is overwritten something is wrong.
733 		 * though we may refetch from append to initiate list
734 		 * processing; in this case - it's ok.
735 		 */
736 		printk(KERN_ERR "%s: prev_desc=0x%p; next_desc=0x%p; "
737 			"prev->hw_next=0x%p\n", __func__, prev_desc,
738 			next_desc, prev_desc ? prev_desc->hw_next : 0);
739 		BUG();
740 	}
741 
742 	local_irq_save(flags);
743 
744 	/* do s/w chaining both for DMA and XOR descriptors */
745 	prev_desc->hw_next = next_desc;
746 
747 	switch (chan->device->id) {
748 	case PPC440SPE_DMA0_ID:
749 	case PPC440SPE_DMA1_ID:
750 		break;
751 	case PPC440SPE_XOR_ID:
752 		/* bind descriptor to the chain */
753 		while (tail->hw_next)
754 			tail = tail->hw_next;
755 		xor_last_linked = tail;
756 
757 		if (prev_desc == xor_last_submit)
758 			/* do not link to the last submitted CB */
759 			break;
760 		ppc440spe_xor_set_link(prev_desc, next_desc);
761 		break;
762 	}
763 
764 	local_irq_restore(flags);
765 }
766 
767 /**
768  * ppc440spe_desc_get_link - get the address of the descriptor that
769  * follows this one
770  */
771 static inline u32 ppc440spe_desc_get_link(struct ppc440spe_adma_desc_slot *desc,
772 					struct ppc440spe_adma_chan *chan)
773 {
774 	if (!desc->hw_next)
775 		return 0;
776 
777 	return desc->hw_next->phys;
778 }
779 
780 /**
781  * ppc440spe_desc_is_aligned - check alignment
782  */
783 static inline int ppc440spe_desc_is_aligned(
784 	struct ppc440spe_adma_desc_slot *desc, int num_slots)
785 {
786 	return (desc->idx & (num_slots - 1)) ? 0 : 1;
787 }
788 
789 /**
790  * ppc440spe_chan_xor_slot_count - get the number of slots necessary for
791  * XOR operation
792  */
793 static int ppc440spe_chan_xor_slot_count(size_t len, int src_cnt,
794 			int *slots_per_op)
795 {
796 	int slot_cnt;
797 
798 	/* each XOR descriptor provides up to 16 source operands */
799 	slot_cnt = *slots_per_op = (src_cnt + XOR_MAX_OPS - 1)/XOR_MAX_OPS;
800 
801 	if (likely(len <= PPC440SPE_ADMA_XOR_MAX_BYTE_COUNT))
802 		return slot_cnt;
803 
804 	printk(KERN_ERR "%s: len %d > max %d !!\n",
805 		__func__, len, PPC440SPE_ADMA_XOR_MAX_BYTE_COUNT);
806 	BUG();
807 	return slot_cnt;
808 }
809 
810 /**
811  * ppc440spe_dma2_pq_slot_count - get the number of slots necessary for
812  * DMA2 PQ operation
813  */
814 static int ppc440spe_dma2_pq_slot_count(dma_addr_t *srcs,
815 		int src_cnt, size_t len)
816 {
817 	signed long long order = 0;
818 	int state = 0;
819 	int addr_count = 0;
820 	int i;
821 	for (i = 1; i < src_cnt; i++) {
822 		dma_addr_t cur_addr = srcs[i];
823 		dma_addr_t old_addr = srcs[i-1];
824 		switch (state) {
825 		case 0:
826 			if (cur_addr == old_addr + len) {
827 				/* direct RXOR */
828 				order = 1;
829 				state = 1;
830 				if (i == src_cnt-1)
831 					addr_count++;
832 			} else if (old_addr == cur_addr + len) {
833 				/* reverse RXOR */
834 				order = -1;
835 				state = 1;
836 				if (i == src_cnt-1)
837 					addr_count++;
838 			} else {
839 				state = 3;
840 			}
841 			break;
842 		case 1:
843 			if (i == src_cnt-2 || (order == -1
844 				&& cur_addr != old_addr - len)) {
845 				order = 0;
846 				state = 0;
847 				addr_count++;
848 			} else if (cur_addr == old_addr + len*order) {
849 				state = 2;
850 				if (i == src_cnt-1)
851 					addr_count++;
852 			} else if (cur_addr == old_addr + 2*len) {
853 				state = 2;
854 				if (i == src_cnt-1)
855 					addr_count++;
856 			} else if (cur_addr == old_addr + 3*len) {
857 				state = 2;
858 				if (i == src_cnt-1)
859 					addr_count++;
860 			} else {
861 				order = 0;
862 				state = 0;
863 				addr_count++;
864 			}
865 			break;
866 		case 2:
867 			order = 0;
868 			state = 0;
869 			addr_count++;
870 				break;
871 		}
872 		if (state == 3)
873 			break;
874 	}
875 	if (src_cnt <= 1 || (state != 1 && state != 2)) {
876 		pr_err("%s: src_cnt=%d, state=%d, addr_count=%d, order=%lld\n",
877 			__func__, src_cnt, state, addr_count, order);
878 		for (i = 0; i < src_cnt; i++)
879 			pr_err("\t[%d] 0x%llx \n", i, srcs[i]);
880 		BUG();
881 	}
882 
883 	return (addr_count + XOR_MAX_OPS - 1) / XOR_MAX_OPS;
884 }
885 
886 
887 /******************************************************************************
888  * ADMA channel low-level routines
889  ******************************************************************************/
890 
891 static u32
892 ppc440spe_chan_get_current_descriptor(struct ppc440spe_adma_chan *chan);
893 static void ppc440spe_chan_append(struct ppc440spe_adma_chan *chan);
894 
895 /**
896  * ppc440spe_adma_device_clear_eot_status - interrupt ack to XOR or DMA engine
897  */
898 static void ppc440spe_adma_device_clear_eot_status(
899 					struct ppc440spe_adma_chan *chan)
900 {
901 	struct dma_regs *dma_reg;
902 	struct xor_regs *xor_reg;
903 	u8 *p = chan->device->dma_desc_pool_virt;
904 	struct dma_cdb *cdb;
905 	u32 rv, i;
906 
907 	switch (chan->device->id) {
908 	case PPC440SPE_DMA0_ID:
909 	case PPC440SPE_DMA1_ID:
910 		/* read FIFO to ack */
911 		dma_reg = chan->device->dma_reg;
912 		while ((rv = ioread32(&dma_reg->csfpl))) {
913 			i = rv & DMA_CDB_ADDR_MSK;
914 			cdb = (struct dma_cdb *)&p[i -
915 			    (u32)chan->device->dma_desc_pool];
916 
917 			/* Clear opcode to ack. This is necessary for
918 			 * ZeroSum operations only
919 			 */
920 			cdb->opc = 0;
921 
922 			if (test_bit(PPC440SPE_RXOR_RUN,
923 			    &ppc440spe_rxor_state)) {
924 				/* probably this is a completed RXOR op,
925 				 * get pointer to CDB using the fact that
926 				 * physical and virtual addresses of CDB
927 				 * in pools have the same offsets
928 				 */
929 				if (le32_to_cpu(cdb->sg1u) &
930 				    DMA_CUED_XOR_BASE) {
931 					/* this is a RXOR */
932 					clear_bit(PPC440SPE_RXOR_RUN,
933 						  &ppc440spe_rxor_state);
934 				}
935 			}
936 
937 			if (rv & DMA_CDB_STATUS_MSK) {
938 				/* ZeroSum check failed
939 				 */
940 				struct ppc440spe_adma_desc_slot *iter;
941 				dma_addr_t phys = rv & ~DMA_CDB_MSK;
942 
943 				/*
944 				 * Update the status of corresponding
945 				 * descriptor.
946 				 */
947 				list_for_each_entry(iter, &chan->chain,
948 				    chain_node) {
949 					if (iter->phys == phys)
950 						break;
951 				}
952 				/*
953 				 * if cannot find the corresponding
954 				 * slot it's a bug
955 				 */
956 				BUG_ON(&iter->chain_node == &chan->chain);
957 
958 				if (iter->xor_check_result) {
959 					if (test_bit(PPC440SPE_DESC_PCHECK,
960 						     &iter->flags)) {
961 						*iter->xor_check_result |=
962 							SUM_CHECK_P_RESULT;
963 					} else
964 					if (test_bit(PPC440SPE_DESC_QCHECK,
965 						     &iter->flags)) {
966 						*iter->xor_check_result |=
967 							SUM_CHECK_Q_RESULT;
968 					} else
969 						BUG();
970 				}
971 			}
972 		}
973 
974 		rv = ioread32(&dma_reg->dsts);
975 		if (rv) {
976 			pr_err("DMA%d err status: 0x%x\n",
977 			       chan->device->id, rv);
978 			/* write back to clear */
979 			iowrite32(rv, &dma_reg->dsts);
980 		}
981 		break;
982 	case PPC440SPE_XOR_ID:
983 		/* reset status bits to ack */
984 		xor_reg = chan->device->xor_reg;
985 		rv = ioread32be(&xor_reg->sr);
986 		iowrite32be(rv, &xor_reg->sr);
987 
988 		if (rv & (XOR_IE_ICBIE_BIT|XOR_IE_ICIE_BIT|XOR_IE_RPTIE_BIT)) {
989 			if (rv & XOR_IE_RPTIE_BIT) {
990 				/* Read PLB Timeout Error.
991 				 * Try to resubmit the CB
992 				 */
993 				u32 val = ioread32be(&xor_reg->ccbalr);
994 
995 				iowrite32be(val, &xor_reg->cblalr);
996 
997 				val = ioread32be(&xor_reg->crsr);
998 				iowrite32be(val | XOR_CRSR_XAE_BIT,
999 					    &xor_reg->crsr);
1000 			} else
1001 				pr_err("XOR ERR 0x%x status\n", rv);
1002 			break;
1003 		}
1004 
1005 		/*  if the XORcore is idle, but there are unprocessed CBs
1006 		 * then refetch the s/w chain here
1007 		 */
1008 		if (!(ioread32be(&xor_reg->sr) & XOR_SR_XCP_BIT) &&
1009 		    do_xor_refetch)
1010 			ppc440spe_chan_append(chan);
1011 		break;
1012 	}
1013 }
1014 
1015 /**
1016  * ppc440spe_chan_is_busy - get the channel status
1017  */
1018 static int ppc440spe_chan_is_busy(struct ppc440spe_adma_chan *chan)
1019 {
1020 	struct dma_regs *dma_reg;
1021 	struct xor_regs *xor_reg;
1022 	int busy = 0;
1023 
1024 	switch (chan->device->id) {
1025 	case PPC440SPE_DMA0_ID:
1026 	case PPC440SPE_DMA1_ID:
1027 		dma_reg = chan->device->dma_reg;
1028 		/*  if command FIFO's head and tail pointers are equal and
1029 		 * status tail is the same as command, then channel is free
1030 		 */
1031 		if (ioread16(&dma_reg->cpfhp) != ioread16(&dma_reg->cpftp) ||
1032 		    ioread16(&dma_reg->cpftp) != ioread16(&dma_reg->csftp))
1033 			busy = 1;
1034 		break;
1035 	case PPC440SPE_XOR_ID:
1036 		/* use the special status bit for the XORcore
1037 		 */
1038 		xor_reg = chan->device->xor_reg;
1039 		busy = (ioread32be(&xor_reg->sr) & XOR_SR_XCP_BIT) ? 1 : 0;
1040 		break;
1041 	}
1042 
1043 	return busy;
1044 }
1045 
1046 /**
1047  * ppc440spe_chan_set_first_xor_descriptor -  init XORcore chain
1048  */
1049 static void ppc440spe_chan_set_first_xor_descriptor(
1050 				struct ppc440spe_adma_chan *chan,
1051 				struct ppc440spe_adma_desc_slot *next_desc)
1052 {
1053 	struct xor_regs *xor_reg = chan->device->xor_reg;
1054 
1055 	if (ioread32be(&xor_reg->sr) & XOR_SR_XCP_BIT)
1056 		printk(KERN_INFO "%s: Warn: XORcore is running "
1057 			"when try to set the first CDB!\n",
1058 			__func__);
1059 
1060 	xor_last_submit = xor_last_linked = next_desc;
1061 
1062 	iowrite32be(XOR_CRSR_64BA_BIT, &xor_reg->crsr);
1063 
1064 	iowrite32be(next_desc->phys, &xor_reg->cblalr);
1065 	iowrite32be(0, &xor_reg->cblahr);
1066 	iowrite32be(ioread32be(&xor_reg->cbcr) | XOR_CBCR_LNK_BIT,
1067 		    &xor_reg->cbcr);
1068 
1069 	chan->hw_chain_inited = 1;
1070 }
1071 
1072 /**
1073  * ppc440spe_dma_put_desc - put DMA0,1 descriptor to FIFO.
1074  * called with irqs disabled
1075  */
1076 static void ppc440spe_dma_put_desc(struct ppc440spe_adma_chan *chan,
1077 		struct ppc440spe_adma_desc_slot *desc)
1078 {
1079 	u32 pcdb;
1080 	struct dma_regs *dma_reg = chan->device->dma_reg;
1081 
1082 	pcdb = desc->phys;
1083 	if (!test_bit(PPC440SPE_DESC_INT, &desc->flags))
1084 		pcdb |= DMA_CDB_NO_INT;
1085 
1086 	chan_last_sub[chan->device->id] = desc;
1087 
1088 	ADMA_LL_DBG(print_cb(chan, desc->hw_desc));
1089 
1090 	iowrite32(pcdb, &dma_reg->cpfpl);
1091 }
1092 
1093 /**
1094  * ppc440spe_chan_append - update the h/w chain in the channel
1095  */
1096 static void ppc440spe_chan_append(struct ppc440spe_adma_chan *chan)
1097 {
1098 	struct xor_regs *xor_reg;
1099 	struct ppc440spe_adma_desc_slot *iter;
1100 	struct xor_cb *xcb;
1101 	u32 cur_desc;
1102 	unsigned long flags;
1103 
1104 	local_irq_save(flags);
1105 
1106 	switch (chan->device->id) {
1107 	case PPC440SPE_DMA0_ID:
1108 	case PPC440SPE_DMA1_ID:
1109 		cur_desc = ppc440spe_chan_get_current_descriptor(chan);
1110 
1111 		if (likely(cur_desc)) {
1112 			iter = chan_last_sub[chan->device->id];
1113 			BUG_ON(!iter);
1114 		} else {
1115 			/* first peer */
1116 			iter = chan_first_cdb[chan->device->id];
1117 			BUG_ON(!iter);
1118 			ppc440spe_dma_put_desc(chan, iter);
1119 			chan->hw_chain_inited = 1;
1120 		}
1121 
1122 		/* is there something new to append */
1123 		if (!iter->hw_next)
1124 			break;
1125 
1126 		/* flush descriptors from the s/w queue to fifo */
1127 		list_for_each_entry_continue(iter, &chan->chain, chain_node) {
1128 			ppc440spe_dma_put_desc(chan, iter);
1129 			if (!iter->hw_next)
1130 				break;
1131 		}
1132 		break;
1133 	case PPC440SPE_XOR_ID:
1134 		/* update h/w links and refetch */
1135 		if (!xor_last_submit->hw_next)
1136 			break;
1137 
1138 		xor_reg = chan->device->xor_reg;
1139 		/* the last linked CDB has to generate an interrupt
1140 		 * that we'd be able to append the next lists to h/w
1141 		 * regardless of the XOR engine state at the moment of
1142 		 * appending of these next lists
1143 		 */
1144 		xcb = xor_last_linked->hw_desc;
1145 		xcb->cbc |= XOR_CBCR_CBCE_BIT;
1146 
1147 		if (!(ioread32be(&xor_reg->sr) & XOR_SR_XCP_BIT)) {
1148 			/* XORcore is idle. Refetch now */
1149 			do_xor_refetch = 0;
1150 			ppc440spe_xor_set_link(xor_last_submit,
1151 				xor_last_submit->hw_next);
1152 
1153 			ADMA_LL_DBG(print_cb_list(chan,
1154 				xor_last_submit->hw_next));
1155 
1156 			xor_last_submit = xor_last_linked;
1157 			iowrite32be(ioread32be(&xor_reg->crsr) |
1158 				    XOR_CRSR_RCBE_BIT | XOR_CRSR_64BA_BIT,
1159 				    &xor_reg->crsr);
1160 		} else {
1161 			/* XORcore is running. Refetch later in the handler */
1162 			do_xor_refetch = 1;
1163 		}
1164 
1165 		break;
1166 	}
1167 
1168 	local_irq_restore(flags);
1169 }
1170 
1171 /**
1172  * ppc440spe_chan_get_current_descriptor - get the currently executed descriptor
1173  */
1174 static u32
1175 ppc440spe_chan_get_current_descriptor(struct ppc440spe_adma_chan *chan)
1176 {
1177 	struct dma_regs *dma_reg;
1178 	struct xor_regs *xor_reg;
1179 
1180 	if (unlikely(!chan->hw_chain_inited))
1181 		/* h/w descriptor chain is not initialized yet */
1182 		return 0;
1183 
1184 	switch (chan->device->id) {
1185 	case PPC440SPE_DMA0_ID:
1186 	case PPC440SPE_DMA1_ID:
1187 		dma_reg = chan->device->dma_reg;
1188 		return ioread32(&dma_reg->acpl) & (~DMA_CDB_MSK);
1189 	case PPC440SPE_XOR_ID:
1190 		xor_reg = chan->device->xor_reg;
1191 		return ioread32be(&xor_reg->ccbalr);
1192 	}
1193 	return 0;
1194 }
1195 
1196 /**
1197  * ppc440spe_chan_run - enable the channel
1198  */
1199 static void ppc440spe_chan_run(struct ppc440spe_adma_chan *chan)
1200 {
1201 	struct xor_regs *xor_reg;
1202 
1203 	switch (chan->device->id) {
1204 	case PPC440SPE_DMA0_ID:
1205 	case PPC440SPE_DMA1_ID:
1206 		/* DMAs are always enabled, do nothing */
1207 		break;
1208 	case PPC440SPE_XOR_ID:
1209 		/* drain write buffer */
1210 		xor_reg = chan->device->xor_reg;
1211 
1212 		/* fetch descriptor pointed to in <link> */
1213 		iowrite32be(XOR_CRSR_64BA_BIT | XOR_CRSR_XAE_BIT,
1214 			    &xor_reg->crsr);
1215 		break;
1216 	}
1217 }
1218 
1219 /******************************************************************************
1220  * ADMA device level
1221  ******************************************************************************/
1222 
1223 static void ppc440spe_chan_start_null_xor(struct ppc440spe_adma_chan *chan);
1224 static int ppc440spe_adma_alloc_chan_resources(struct dma_chan *chan);
1225 
1226 static dma_cookie_t
1227 ppc440spe_adma_tx_submit(struct dma_async_tx_descriptor *tx);
1228 
1229 static void ppc440spe_adma_set_dest(struct ppc440spe_adma_desc_slot *tx,
1230 				    dma_addr_t addr, int index);
1231 static void
1232 ppc440spe_adma_memcpy_xor_set_src(struct ppc440spe_adma_desc_slot *tx,
1233 				  dma_addr_t addr, int index);
1234 
1235 static void
1236 ppc440spe_adma_pq_set_dest(struct ppc440spe_adma_desc_slot *tx,
1237 			   dma_addr_t *paddr, unsigned long flags);
1238 static void
1239 ppc440spe_adma_pq_set_src(struct ppc440spe_adma_desc_slot *tx,
1240 			  dma_addr_t addr, int index);
1241 static void
1242 ppc440spe_adma_pq_set_src_mult(struct ppc440spe_adma_desc_slot *tx,
1243 			       unsigned char mult, int index, int dst_pos);
1244 static void
1245 ppc440spe_adma_pqzero_sum_set_dest(struct ppc440spe_adma_desc_slot *tx,
1246 				   dma_addr_t paddr, dma_addr_t qaddr);
1247 
1248 static struct page *ppc440spe_rxor_srcs[32];
1249 
1250 /**
1251  * ppc440spe_can_rxor - check if the operands may be processed with RXOR
1252  */
1253 static int ppc440spe_can_rxor(struct page **srcs, int src_cnt, size_t len)
1254 {
1255 	int i, order = 0, state = 0;
1256 	int idx = 0;
1257 
1258 	if (unlikely(!(src_cnt > 1)))
1259 		return 0;
1260 
1261 	BUG_ON(src_cnt > ARRAY_SIZE(ppc440spe_rxor_srcs));
1262 
1263 	/* Skip holes in the source list before checking */
1264 	for (i = 0; i < src_cnt; i++) {
1265 		if (!srcs[i])
1266 			continue;
1267 		ppc440spe_rxor_srcs[idx++] = srcs[i];
1268 	}
1269 	src_cnt = idx;
1270 
1271 	for (i = 1; i < src_cnt; i++) {
1272 		char *cur_addr = page_address(ppc440spe_rxor_srcs[i]);
1273 		char *old_addr = page_address(ppc440spe_rxor_srcs[i - 1]);
1274 
1275 		switch (state) {
1276 		case 0:
1277 			if (cur_addr == old_addr + len) {
1278 				/* direct RXOR */
1279 				order = 1;
1280 				state = 1;
1281 			} else if (old_addr == cur_addr + len) {
1282 				/* reverse RXOR */
1283 				order = -1;
1284 				state = 1;
1285 			} else
1286 				goto out;
1287 			break;
1288 		case 1:
1289 			if ((i == src_cnt - 2) ||
1290 			    (order == -1 && cur_addr != old_addr - len)) {
1291 				order = 0;
1292 				state = 0;
1293 			} else if ((cur_addr == old_addr + len * order) ||
1294 				   (cur_addr == old_addr + 2 * len) ||
1295 				   (cur_addr == old_addr + 3 * len)) {
1296 				state = 2;
1297 			} else {
1298 				order = 0;
1299 				state = 0;
1300 			}
1301 			break;
1302 		case 2:
1303 			order = 0;
1304 			state = 0;
1305 			break;
1306 		}
1307 	}
1308 
1309 out:
1310 	if (state == 1 || state == 2)
1311 		return 1;
1312 
1313 	return 0;
1314 }
1315 
1316 /**
1317  * ppc440spe_adma_device_estimate - estimate the efficiency of processing
1318  *	the operation given on this channel. It's assumed that 'chan' is
1319  *	capable to process 'cap' type of operation.
1320  * @chan: channel to use
1321  * @cap: type of transaction
1322  * @dst_lst: array of destination pointers
1323  * @dst_cnt: number of destination operands
1324  * @src_lst: array of source pointers
1325  * @src_cnt: number of source operands
1326  * @src_sz: size of each source operand
1327  */
1328 static int ppc440spe_adma_estimate(struct dma_chan *chan,
1329 	enum dma_transaction_type cap, struct page **dst_lst, int dst_cnt,
1330 	struct page **src_lst, int src_cnt, size_t src_sz)
1331 {
1332 	int ef = 1;
1333 
1334 	if (cap == DMA_PQ || cap == DMA_PQ_VAL) {
1335 		/* If RAID-6 capabilities were not activated don't try
1336 		 * to use them
1337 		 */
1338 		if (unlikely(!ppc440spe_r6_enabled))
1339 			return -1;
1340 	}
1341 	/*  In the current implementation of ppc440spe ADMA driver it
1342 	 * makes sense to pick out only pq case, because it may be
1343 	 * processed:
1344 	 * (1) either using Biskup method on DMA2;
1345 	 * (2) or on DMA0/1.
1346 	 *  Thus we give a favour to (1) if the sources are suitable;
1347 	 * else let it be processed on one of the DMA0/1 engines.
1348 	 *  In the sum_product case where destination is also the
1349 	 * source process it on DMA0/1 only.
1350 	 */
1351 	if (cap == DMA_PQ && chan->chan_id == PPC440SPE_XOR_ID) {
1352 
1353 		if (dst_cnt == 1 && src_cnt == 2 && dst_lst[0] == src_lst[1])
1354 			ef = 0; /* sum_product case, process on DMA0/1 */
1355 		else if (ppc440spe_can_rxor(src_lst, src_cnt, src_sz))
1356 			ef = 3; /* override (DMA0/1 + idle) */
1357 		else
1358 			ef = 0; /* can't process on DMA2 if !rxor */
1359 	}
1360 
1361 	/* channel idleness increases the priority */
1362 	if (likely(ef) &&
1363 	    !ppc440spe_chan_is_busy(to_ppc440spe_adma_chan(chan)))
1364 		ef++;
1365 
1366 	return ef;
1367 }
1368 
1369 struct dma_chan *
1370 ppc440spe_async_tx_find_best_channel(enum dma_transaction_type cap,
1371 	struct page **dst_lst, int dst_cnt, struct page **src_lst,
1372 	int src_cnt, size_t src_sz)
1373 {
1374 	struct dma_chan *best_chan = NULL;
1375 	struct ppc_dma_chan_ref *ref;
1376 	int best_rank = -1;
1377 
1378 	if (unlikely(!src_sz))
1379 		return NULL;
1380 	if (src_sz > PAGE_SIZE) {
1381 		/*
1382 		 * should a user of the api ever pass > PAGE_SIZE requests
1383 		 * we sort out cases where temporary page-sized buffers
1384 		 * are used.
1385 		 */
1386 		switch (cap) {
1387 		case DMA_PQ:
1388 			if (src_cnt == 1 && dst_lst[1] == src_lst[0])
1389 				return NULL;
1390 			if (src_cnt == 2 && dst_lst[1] == src_lst[1])
1391 				return NULL;
1392 			break;
1393 		case DMA_PQ_VAL:
1394 		case DMA_XOR_VAL:
1395 			return NULL;
1396 		default:
1397 			break;
1398 		}
1399 	}
1400 
1401 	list_for_each_entry(ref, &ppc440spe_adma_chan_list, node) {
1402 		if (dma_has_cap(cap, ref->chan->device->cap_mask)) {
1403 			int rank;
1404 
1405 			rank = ppc440spe_adma_estimate(ref->chan, cap, dst_lst,
1406 					dst_cnt, src_lst, src_cnt, src_sz);
1407 			if (rank > best_rank) {
1408 				best_rank = rank;
1409 				best_chan = ref->chan;
1410 			}
1411 		}
1412 	}
1413 
1414 	return best_chan;
1415 }
1416 EXPORT_SYMBOL_GPL(ppc440spe_async_tx_find_best_channel);
1417 
1418 /**
1419  * ppc440spe_get_group_entry - get group entry with index idx
1420  * @tdesc: is the last allocated slot in the group.
1421  */
1422 static struct ppc440spe_adma_desc_slot *
1423 ppc440spe_get_group_entry(struct ppc440spe_adma_desc_slot *tdesc, u32 entry_idx)
1424 {
1425 	struct ppc440spe_adma_desc_slot *iter = tdesc->group_head;
1426 	int i = 0;
1427 
1428 	if (entry_idx < 0 || entry_idx >= (tdesc->src_cnt + tdesc->dst_cnt)) {
1429 		printk("%s: entry_idx %d, src_cnt %d, dst_cnt %d\n",
1430 			__func__, entry_idx, tdesc->src_cnt, tdesc->dst_cnt);
1431 		BUG();
1432 	}
1433 
1434 	list_for_each_entry(iter, &tdesc->group_list, chain_node) {
1435 		if (i++ == entry_idx)
1436 			break;
1437 	}
1438 	return iter;
1439 }
1440 
1441 /**
1442  * ppc440spe_adma_free_slots - flags descriptor slots for reuse
1443  * @slot: Slot to free
1444  * Caller must hold &ppc440spe_chan->lock while calling this function
1445  */
1446 static void ppc440spe_adma_free_slots(struct ppc440spe_adma_desc_slot *slot,
1447 				      struct ppc440spe_adma_chan *chan)
1448 {
1449 	int stride = slot->slots_per_op;
1450 
1451 	while (stride--) {
1452 		slot->slots_per_op = 0;
1453 		slot = list_entry(slot->slot_node.next,
1454 				struct ppc440spe_adma_desc_slot,
1455 				slot_node);
1456 	}
1457 }
1458 
1459 /**
1460  * ppc440spe_adma_run_tx_complete_actions - call functions to be called
1461  * upon completion
1462  */
1463 static dma_cookie_t ppc440spe_adma_run_tx_complete_actions(
1464 		struct ppc440spe_adma_desc_slot *desc,
1465 		struct ppc440spe_adma_chan *chan,
1466 		dma_cookie_t cookie)
1467 {
1468 	BUG_ON(desc->async_tx.cookie < 0);
1469 	if (desc->async_tx.cookie > 0) {
1470 		cookie = desc->async_tx.cookie;
1471 		desc->async_tx.cookie = 0;
1472 
1473 		dma_descriptor_unmap(&desc->async_tx);
1474 		/* call the callback (must not sleep or submit new
1475 		 * operations to this channel)
1476 		 */
1477 		dmaengine_desc_get_callback_invoke(&desc->async_tx, NULL);
1478 	}
1479 
1480 	/* run dependent operations */
1481 	dma_run_dependencies(&desc->async_tx);
1482 
1483 	return cookie;
1484 }
1485 
1486 /**
1487  * ppc440spe_adma_clean_slot - clean up CDB slot (if ack is set)
1488  */
1489 static int ppc440spe_adma_clean_slot(struct ppc440spe_adma_desc_slot *desc,
1490 		struct ppc440spe_adma_chan *chan)
1491 {
1492 	/* the client is allowed to attach dependent operations
1493 	 * until 'ack' is set
1494 	 */
1495 	if (!async_tx_test_ack(&desc->async_tx))
1496 		return 0;
1497 
1498 	/* leave the last descriptor in the chain
1499 	 * so we can append to it
1500 	 */
1501 	if (list_is_last(&desc->chain_node, &chan->chain) ||
1502 	    desc->phys == ppc440spe_chan_get_current_descriptor(chan))
1503 		return 1;
1504 
1505 	if (chan->device->id != PPC440SPE_XOR_ID) {
1506 		/* our DMA interrupt handler clears opc field of
1507 		 * each processed descriptor. For all types of
1508 		 * operations except for ZeroSum we do not actually
1509 		 * need ack from the interrupt handler. ZeroSum is a
1510 		 * special case since the result of this operation
1511 		 * is available from the handler only, so if we see
1512 		 * such type of descriptor (which is unprocessed yet)
1513 		 * then leave it in chain.
1514 		 */
1515 		struct dma_cdb *cdb = desc->hw_desc;
1516 		if (cdb->opc == DMA_CDB_OPC_DCHECK128)
1517 			return 1;
1518 	}
1519 
1520 	dev_dbg(chan->device->common.dev, "\tfree slot %llx: %d stride: %d\n",
1521 		desc->phys, desc->idx, desc->slots_per_op);
1522 
1523 	list_del(&desc->chain_node);
1524 	ppc440spe_adma_free_slots(desc, chan);
1525 	return 0;
1526 }
1527 
1528 /**
1529  * __ppc440spe_adma_slot_cleanup - this is the common clean-up routine
1530  *	which runs through the channel CDBs list until reach the descriptor
1531  *	currently processed. When routine determines that all CDBs of group
1532  *	are completed then corresponding callbacks (if any) are called and slots
1533  *	are freed.
1534  */
1535 static void __ppc440spe_adma_slot_cleanup(struct ppc440spe_adma_chan *chan)
1536 {
1537 	struct ppc440spe_adma_desc_slot *iter, *_iter, *group_start = NULL;
1538 	dma_cookie_t cookie = 0;
1539 	u32 current_desc = ppc440spe_chan_get_current_descriptor(chan);
1540 	int busy = ppc440spe_chan_is_busy(chan);
1541 	int seen_current = 0, slot_cnt = 0, slots_per_op = 0;
1542 
1543 	dev_dbg(chan->device->common.dev, "ppc440spe adma%d: %s\n",
1544 		chan->device->id, __func__);
1545 
1546 	if (!current_desc) {
1547 		/*  There were no transactions yet, so
1548 		 * nothing to clean
1549 		 */
1550 		return;
1551 	}
1552 
1553 	/* free completed slots from the chain starting with
1554 	 * the oldest descriptor
1555 	 */
1556 	list_for_each_entry_safe(iter, _iter, &chan->chain,
1557 					chain_node) {
1558 		dev_dbg(chan->device->common.dev, "\tcookie: %d slot: %d "
1559 		    "busy: %d this_desc: %#llx next_desc: %#x "
1560 		    "cur: %#x ack: %d\n",
1561 		    iter->async_tx.cookie, iter->idx, busy, iter->phys,
1562 		    ppc440spe_desc_get_link(iter, chan), current_desc,
1563 		    async_tx_test_ack(&iter->async_tx));
1564 		prefetch(_iter);
1565 		prefetch(&_iter->async_tx);
1566 
1567 		/* do not advance past the current descriptor loaded into the
1568 		 * hardware channel,subsequent descriptors are either in process
1569 		 * or have not been submitted
1570 		 */
1571 		if (seen_current)
1572 			break;
1573 
1574 		/* stop the search if we reach the current descriptor and the
1575 		 * channel is busy, or if it appears that the current descriptor
1576 		 * needs to be re-read (i.e. has been appended to)
1577 		 */
1578 		if (iter->phys == current_desc) {
1579 			BUG_ON(seen_current++);
1580 			if (busy || ppc440spe_desc_get_link(iter, chan)) {
1581 				/* not all descriptors of the group have
1582 				 * been completed; exit.
1583 				 */
1584 				break;
1585 			}
1586 		}
1587 
1588 		/* detect the start of a group transaction */
1589 		if (!slot_cnt && !slots_per_op) {
1590 			slot_cnt = iter->slot_cnt;
1591 			slots_per_op = iter->slots_per_op;
1592 			if (slot_cnt <= slots_per_op) {
1593 				slot_cnt = 0;
1594 				slots_per_op = 0;
1595 			}
1596 		}
1597 
1598 		if (slot_cnt) {
1599 			if (!group_start)
1600 				group_start = iter;
1601 			slot_cnt -= slots_per_op;
1602 		}
1603 
1604 		/* all the members of a group are complete */
1605 		if (slots_per_op != 0 && slot_cnt == 0) {
1606 			struct ppc440spe_adma_desc_slot *grp_iter, *_grp_iter;
1607 			int end_of_chain = 0;
1608 
1609 			/* clean up the group */
1610 			slot_cnt = group_start->slot_cnt;
1611 			grp_iter = group_start;
1612 			list_for_each_entry_safe_from(grp_iter, _grp_iter,
1613 				&chan->chain, chain_node) {
1614 
1615 				cookie = ppc440spe_adma_run_tx_complete_actions(
1616 					grp_iter, chan, cookie);
1617 
1618 				slot_cnt -= slots_per_op;
1619 				end_of_chain = ppc440spe_adma_clean_slot(
1620 				    grp_iter, chan);
1621 				if (end_of_chain && slot_cnt) {
1622 					/* Should wait for ZeroSum completion */
1623 					if (cookie > 0)
1624 						chan->common.completed_cookie = cookie;
1625 					return;
1626 				}
1627 
1628 				if (slot_cnt == 0 || end_of_chain)
1629 					break;
1630 			}
1631 
1632 			/* the group should be complete at this point */
1633 			BUG_ON(slot_cnt);
1634 
1635 			slots_per_op = 0;
1636 			group_start = NULL;
1637 			if (end_of_chain)
1638 				break;
1639 			else
1640 				continue;
1641 		} else if (slots_per_op) /* wait for group completion */
1642 			continue;
1643 
1644 		cookie = ppc440spe_adma_run_tx_complete_actions(iter, chan,
1645 		    cookie);
1646 
1647 		if (ppc440spe_adma_clean_slot(iter, chan))
1648 			break;
1649 	}
1650 
1651 	BUG_ON(!seen_current);
1652 
1653 	if (cookie > 0) {
1654 		chan->common.completed_cookie = cookie;
1655 		pr_debug("\tcompleted cookie %d\n", cookie);
1656 	}
1657 
1658 }
1659 
1660 /**
1661  * ppc440spe_adma_tasklet - clean up watch-dog initiator
1662  */
1663 static void ppc440spe_adma_tasklet(unsigned long data)
1664 {
1665 	struct ppc440spe_adma_chan *chan = (struct ppc440spe_adma_chan *) data;
1666 
1667 	spin_lock_nested(&chan->lock, SINGLE_DEPTH_NESTING);
1668 	__ppc440spe_adma_slot_cleanup(chan);
1669 	spin_unlock(&chan->lock);
1670 }
1671 
1672 /**
1673  * ppc440spe_adma_slot_cleanup - clean up scheduled initiator
1674  */
1675 static void ppc440spe_adma_slot_cleanup(struct ppc440spe_adma_chan *chan)
1676 {
1677 	spin_lock_bh(&chan->lock);
1678 	__ppc440spe_adma_slot_cleanup(chan);
1679 	spin_unlock_bh(&chan->lock);
1680 }
1681 
1682 /**
1683  * ppc440spe_adma_alloc_slots - allocate free slots (if any)
1684  */
1685 static struct ppc440spe_adma_desc_slot *ppc440spe_adma_alloc_slots(
1686 		struct ppc440spe_adma_chan *chan, int num_slots,
1687 		int slots_per_op)
1688 {
1689 	struct ppc440spe_adma_desc_slot *iter = NULL, *_iter;
1690 	struct ppc440spe_adma_desc_slot *alloc_start = NULL;
1691 	struct list_head chain = LIST_HEAD_INIT(chain);
1692 	int slots_found, retry = 0;
1693 
1694 
1695 	BUG_ON(!num_slots || !slots_per_op);
1696 	/* start search from the last allocated descrtiptor
1697 	 * if a contiguous allocation can not be found start searching
1698 	 * from the beginning of the list
1699 	 */
1700 retry:
1701 	slots_found = 0;
1702 	if (retry == 0)
1703 		iter = chan->last_used;
1704 	else
1705 		iter = list_entry(&chan->all_slots,
1706 				  struct ppc440spe_adma_desc_slot,
1707 				  slot_node);
1708 	list_for_each_entry_safe_continue(iter, _iter, &chan->all_slots,
1709 	    slot_node) {
1710 		prefetch(_iter);
1711 		prefetch(&_iter->async_tx);
1712 		if (iter->slots_per_op) {
1713 			slots_found = 0;
1714 			continue;
1715 		}
1716 
1717 		/* start the allocation if the slot is correctly aligned */
1718 		if (!slots_found++)
1719 			alloc_start = iter;
1720 
1721 		if (slots_found == num_slots) {
1722 			struct ppc440spe_adma_desc_slot *alloc_tail = NULL;
1723 			struct ppc440spe_adma_desc_slot *last_used = NULL;
1724 
1725 			iter = alloc_start;
1726 			while (num_slots) {
1727 				int i;
1728 				/* pre-ack all but the last descriptor */
1729 				if (num_slots != slots_per_op)
1730 					async_tx_ack(&iter->async_tx);
1731 
1732 				list_add_tail(&iter->chain_node, &chain);
1733 				alloc_tail = iter;
1734 				iter->async_tx.cookie = 0;
1735 				iter->hw_next = NULL;
1736 				iter->flags = 0;
1737 				iter->slot_cnt = num_slots;
1738 				iter->xor_check_result = NULL;
1739 				for (i = 0; i < slots_per_op; i++) {
1740 					iter->slots_per_op = slots_per_op - i;
1741 					last_used = iter;
1742 					iter = list_entry(iter->slot_node.next,
1743 						struct ppc440spe_adma_desc_slot,
1744 						slot_node);
1745 				}
1746 				num_slots -= slots_per_op;
1747 			}
1748 			alloc_tail->group_head = alloc_start;
1749 			alloc_tail->async_tx.cookie = -EBUSY;
1750 			list_splice(&chain, &alloc_tail->group_list);
1751 			chan->last_used = last_used;
1752 			return alloc_tail;
1753 		}
1754 	}
1755 	if (!retry++)
1756 		goto retry;
1757 
1758 	/* try to free some slots if the allocation fails */
1759 	tasklet_schedule(&chan->irq_tasklet);
1760 	return NULL;
1761 }
1762 
1763 /**
1764  * ppc440spe_adma_alloc_chan_resources -  allocate pools for CDB slots
1765  */
1766 static int ppc440spe_adma_alloc_chan_resources(struct dma_chan *chan)
1767 {
1768 	struct ppc440spe_adma_chan *ppc440spe_chan;
1769 	struct ppc440spe_adma_desc_slot *slot = NULL;
1770 	char *hw_desc;
1771 	int i, db_sz;
1772 	int init;
1773 
1774 	ppc440spe_chan = to_ppc440spe_adma_chan(chan);
1775 	init = ppc440spe_chan->slots_allocated ? 0 : 1;
1776 	chan->chan_id = ppc440spe_chan->device->id;
1777 
1778 	/* Allocate descriptor slots */
1779 	i = ppc440spe_chan->slots_allocated;
1780 	if (ppc440spe_chan->device->id != PPC440SPE_XOR_ID)
1781 		db_sz = sizeof(struct dma_cdb);
1782 	else
1783 		db_sz = sizeof(struct xor_cb);
1784 
1785 	for (; i < (ppc440spe_chan->device->pool_size / db_sz); i++) {
1786 		slot = kzalloc(sizeof(struct ppc440spe_adma_desc_slot),
1787 			       GFP_KERNEL);
1788 		if (!slot) {
1789 			printk(KERN_INFO "SPE ADMA Channel only initialized"
1790 				" %d descriptor slots", i--);
1791 			break;
1792 		}
1793 
1794 		hw_desc = (char *) ppc440spe_chan->device->dma_desc_pool_virt;
1795 		slot->hw_desc = (void *) &hw_desc[i * db_sz];
1796 		dma_async_tx_descriptor_init(&slot->async_tx, chan);
1797 		slot->async_tx.tx_submit = ppc440spe_adma_tx_submit;
1798 		INIT_LIST_HEAD(&slot->chain_node);
1799 		INIT_LIST_HEAD(&slot->slot_node);
1800 		INIT_LIST_HEAD(&slot->group_list);
1801 		slot->phys = ppc440spe_chan->device->dma_desc_pool + i * db_sz;
1802 		slot->idx = i;
1803 
1804 		spin_lock_bh(&ppc440spe_chan->lock);
1805 		ppc440spe_chan->slots_allocated++;
1806 		list_add_tail(&slot->slot_node, &ppc440spe_chan->all_slots);
1807 		spin_unlock_bh(&ppc440spe_chan->lock);
1808 	}
1809 
1810 	if (i && !ppc440spe_chan->last_used) {
1811 		ppc440spe_chan->last_used =
1812 			list_entry(ppc440spe_chan->all_slots.next,
1813 				struct ppc440spe_adma_desc_slot,
1814 				slot_node);
1815 	}
1816 
1817 	dev_dbg(ppc440spe_chan->device->common.dev,
1818 		"ppc440spe adma%d: allocated %d descriptor slots\n",
1819 		ppc440spe_chan->device->id, i);
1820 
1821 	/* initialize the channel and the chain with a null operation */
1822 	if (init) {
1823 		switch (ppc440spe_chan->device->id) {
1824 		case PPC440SPE_DMA0_ID:
1825 		case PPC440SPE_DMA1_ID:
1826 			ppc440spe_chan->hw_chain_inited = 0;
1827 			/* Use WXOR for self-testing */
1828 			if (!ppc440spe_r6_tchan)
1829 				ppc440spe_r6_tchan = ppc440spe_chan;
1830 			break;
1831 		case PPC440SPE_XOR_ID:
1832 			ppc440spe_chan_start_null_xor(ppc440spe_chan);
1833 			break;
1834 		default:
1835 			BUG();
1836 		}
1837 		ppc440spe_chan->needs_unmap = 1;
1838 	}
1839 
1840 	return (i > 0) ? i : -ENOMEM;
1841 }
1842 
1843 /**
1844  * ppc440spe_rxor_set_region_data -
1845  */
1846 static void ppc440spe_rxor_set_region(struct ppc440spe_adma_desc_slot *desc,
1847 	u8 xor_arg_no, u32 mask)
1848 {
1849 	struct xor_cb *xcb = desc->hw_desc;
1850 
1851 	xcb->ops[xor_arg_no].h |= mask;
1852 }
1853 
1854 /**
1855  * ppc440spe_rxor_set_src -
1856  */
1857 static void ppc440spe_rxor_set_src(struct ppc440spe_adma_desc_slot *desc,
1858 	u8 xor_arg_no, dma_addr_t addr)
1859 {
1860 	struct xor_cb *xcb = desc->hw_desc;
1861 
1862 	xcb->ops[xor_arg_no].h |= DMA_CUED_XOR_BASE;
1863 	xcb->ops[xor_arg_no].l = addr;
1864 }
1865 
1866 /**
1867  * ppc440spe_rxor_set_mult -
1868  */
1869 static void ppc440spe_rxor_set_mult(struct ppc440spe_adma_desc_slot *desc,
1870 	u8 xor_arg_no, u8 idx, u8 mult)
1871 {
1872 	struct xor_cb *xcb = desc->hw_desc;
1873 
1874 	xcb->ops[xor_arg_no].h |= mult << (DMA_CUED_MULT1_OFF + idx * 8);
1875 }
1876 
1877 /**
1878  * ppc440spe_adma_check_threshold - append CDBs to h/w chain if threshold
1879  *	has been achieved
1880  */
1881 static void ppc440spe_adma_check_threshold(struct ppc440spe_adma_chan *chan)
1882 {
1883 	dev_dbg(chan->device->common.dev, "ppc440spe adma%d: pending: %d\n",
1884 		chan->device->id, chan->pending);
1885 
1886 	if (chan->pending >= PPC440SPE_ADMA_THRESHOLD) {
1887 		chan->pending = 0;
1888 		ppc440spe_chan_append(chan);
1889 	}
1890 }
1891 
1892 /**
1893  * ppc440spe_adma_tx_submit - submit new descriptor group to the channel
1894  *	(it's not necessary that descriptors will be submitted to the h/w
1895  *	chains too right now)
1896  */
1897 static dma_cookie_t ppc440spe_adma_tx_submit(struct dma_async_tx_descriptor *tx)
1898 {
1899 	struct ppc440spe_adma_desc_slot *sw_desc;
1900 	struct ppc440spe_adma_chan *chan = to_ppc440spe_adma_chan(tx->chan);
1901 	struct ppc440spe_adma_desc_slot *group_start, *old_chain_tail;
1902 	int slot_cnt;
1903 	int slots_per_op;
1904 	dma_cookie_t cookie;
1905 
1906 	sw_desc = tx_to_ppc440spe_adma_slot(tx);
1907 
1908 	group_start = sw_desc->group_head;
1909 	slot_cnt = group_start->slot_cnt;
1910 	slots_per_op = group_start->slots_per_op;
1911 
1912 	spin_lock_bh(&chan->lock);
1913 	cookie = dma_cookie_assign(tx);
1914 
1915 	if (unlikely(list_empty(&chan->chain))) {
1916 		/* first peer */
1917 		list_splice_init(&sw_desc->group_list, &chan->chain);
1918 		chan_first_cdb[chan->device->id] = group_start;
1919 	} else {
1920 		/* isn't first peer, bind CDBs to chain */
1921 		old_chain_tail = list_entry(chan->chain.prev,
1922 					struct ppc440spe_adma_desc_slot,
1923 					chain_node);
1924 		list_splice_init(&sw_desc->group_list,
1925 		    &old_chain_tail->chain_node);
1926 		/* fix up the hardware chain */
1927 		ppc440spe_desc_set_link(chan, old_chain_tail, group_start);
1928 	}
1929 
1930 	/* increment the pending count by the number of operations */
1931 	chan->pending += slot_cnt / slots_per_op;
1932 	ppc440spe_adma_check_threshold(chan);
1933 	spin_unlock_bh(&chan->lock);
1934 
1935 	dev_dbg(chan->device->common.dev,
1936 		"ppc440spe adma%d: %s cookie: %d slot: %d tx %p\n",
1937 		chan->device->id, __func__,
1938 		sw_desc->async_tx.cookie, sw_desc->idx, sw_desc);
1939 
1940 	return cookie;
1941 }
1942 
1943 /**
1944  * ppc440spe_adma_prep_dma_interrupt - prepare CDB for a pseudo DMA operation
1945  */
1946 static struct dma_async_tx_descriptor *ppc440spe_adma_prep_dma_interrupt(
1947 		struct dma_chan *chan, unsigned long flags)
1948 {
1949 	struct ppc440spe_adma_chan *ppc440spe_chan;
1950 	struct ppc440spe_adma_desc_slot *sw_desc, *group_start;
1951 	int slot_cnt, slots_per_op;
1952 
1953 	ppc440spe_chan = to_ppc440spe_adma_chan(chan);
1954 
1955 	dev_dbg(ppc440spe_chan->device->common.dev,
1956 		"ppc440spe adma%d: %s\n", ppc440spe_chan->device->id,
1957 		__func__);
1958 
1959 	spin_lock_bh(&ppc440spe_chan->lock);
1960 	slot_cnt = slots_per_op = 1;
1961 	sw_desc = ppc440spe_adma_alloc_slots(ppc440spe_chan, slot_cnt,
1962 			slots_per_op);
1963 	if (sw_desc) {
1964 		group_start = sw_desc->group_head;
1965 		ppc440spe_desc_init_interrupt(group_start, ppc440spe_chan);
1966 		group_start->unmap_len = 0;
1967 		sw_desc->async_tx.flags = flags;
1968 	}
1969 	spin_unlock_bh(&ppc440spe_chan->lock);
1970 
1971 	return sw_desc ? &sw_desc->async_tx : NULL;
1972 }
1973 
1974 /**
1975  * ppc440spe_adma_prep_dma_memcpy - prepare CDB for a MEMCPY operation
1976  */
1977 static struct dma_async_tx_descriptor *ppc440spe_adma_prep_dma_memcpy(
1978 		struct dma_chan *chan, dma_addr_t dma_dest,
1979 		dma_addr_t dma_src, size_t len, unsigned long flags)
1980 {
1981 	struct ppc440spe_adma_chan *ppc440spe_chan;
1982 	struct ppc440spe_adma_desc_slot *sw_desc, *group_start;
1983 	int slot_cnt, slots_per_op;
1984 
1985 	ppc440spe_chan = to_ppc440spe_adma_chan(chan);
1986 
1987 	if (unlikely(!len))
1988 		return NULL;
1989 
1990 	BUG_ON(len > PPC440SPE_ADMA_DMA_MAX_BYTE_COUNT);
1991 
1992 	spin_lock_bh(&ppc440spe_chan->lock);
1993 
1994 	dev_dbg(ppc440spe_chan->device->common.dev,
1995 		"ppc440spe adma%d: %s len: %u int_en %d\n",
1996 		ppc440spe_chan->device->id, __func__, len,
1997 		flags & DMA_PREP_INTERRUPT ? 1 : 0);
1998 	slot_cnt = slots_per_op = 1;
1999 	sw_desc = ppc440spe_adma_alloc_slots(ppc440spe_chan, slot_cnt,
2000 		slots_per_op);
2001 	if (sw_desc) {
2002 		group_start = sw_desc->group_head;
2003 		ppc440spe_desc_init_memcpy(group_start, flags);
2004 		ppc440spe_adma_set_dest(group_start, dma_dest, 0);
2005 		ppc440spe_adma_memcpy_xor_set_src(group_start, dma_src, 0);
2006 		ppc440spe_desc_set_byte_count(group_start, ppc440spe_chan, len);
2007 		sw_desc->unmap_len = len;
2008 		sw_desc->async_tx.flags = flags;
2009 	}
2010 	spin_unlock_bh(&ppc440spe_chan->lock);
2011 
2012 	return sw_desc ? &sw_desc->async_tx : NULL;
2013 }
2014 
2015 /**
2016  * ppc440spe_adma_prep_dma_xor - prepare CDB for a XOR operation
2017  */
2018 static struct dma_async_tx_descriptor *ppc440spe_adma_prep_dma_xor(
2019 		struct dma_chan *chan, dma_addr_t dma_dest,
2020 		dma_addr_t *dma_src, u32 src_cnt, size_t len,
2021 		unsigned long flags)
2022 {
2023 	struct ppc440spe_adma_chan *ppc440spe_chan;
2024 	struct ppc440spe_adma_desc_slot *sw_desc, *group_start;
2025 	int slot_cnt, slots_per_op;
2026 
2027 	ppc440spe_chan = to_ppc440spe_adma_chan(chan);
2028 
2029 	ADMA_LL_DBG(prep_dma_xor_dbg(ppc440spe_chan->device->id,
2030 				     dma_dest, dma_src, src_cnt));
2031 	if (unlikely(!len))
2032 		return NULL;
2033 	BUG_ON(len > PPC440SPE_ADMA_XOR_MAX_BYTE_COUNT);
2034 
2035 	dev_dbg(ppc440spe_chan->device->common.dev,
2036 		"ppc440spe adma%d: %s src_cnt: %d len: %u int_en: %d\n",
2037 		ppc440spe_chan->device->id, __func__, src_cnt, len,
2038 		flags & DMA_PREP_INTERRUPT ? 1 : 0);
2039 
2040 	spin_lock_bh(&ppc440spe_chan->lock);
2041 	slot_cnt = ppc440spe_chan_xor_slot_count(len, src_cnt, &slots_per_op);
2042 	sw_desc = ppc440spe_adma_alloc_slots(ppc440spe_chan, slot_cnt,
2043 			slots_per_op);
2044 	if (sw_desc) {
2045 		group_start = sw_desc->group_head;
2046 		ppc440spe_desc_init_xor(group_start, src_cnt, flags);
2047 		ppc440spe_adma_set_dest(group_start, dma_dest, 0);
2048 		while (src_cnt--)
2049 			ppc440spe_adma_memcpy_xor_set_src(group_start,
2050 				dma_src[src_cnt], src_cnt);
2051 		ppc440spe_desc_set_byte_count(group_start, ppc440spe_chan, len);
2052 		sw_desc->unmap_len = len;
2053 		sw_desc->async_tx.flags = flags;
2054 	}
2055 	spin_unlock_bh(&ppc440spe_chan->lock);
2056 
2057 	return sw_desc ? &sw_desc->async_tx : NULL;
2058 }
2059 
2060 static inline void
2061 ppc440spe_desc_set_xor_src_cnt(struct ppc440spe_adma_desc_slot *desc,
2062 				int src_cnt);
2063 static void ppc440spe_init_rxor_cursor(struct ppc440spe_rxor *cursor);
2064 
2065 /**
2066  * ppc440spe_adma_init_dma2rxor_slot -
2067  */
2068 static void ppc440spe_adma_init_dma2rxor_slot(
2069 		struct ppc440spe_adma_desc_slot *desc,
2070 		dma_addr_t *src, int src_cnt)
2071 {
2072 	int i;
2073 
2074 	/* initialize CDB */
2075 	for (i = 0; i < src_cnt; i++) {
2076 		ppc440spe_adma_dma2rxor_prep_src(desc, &desc->rxor_cursor, i,
2077 						 desc->src_cnt, (u32)src[i]);
2078 	}
2079 }
2080 
2081 /**
2082  * ppc440spe_dma01_prep_mult -
2083  * for Q operation where destination is also the source
2084  */
2085 static struct ppc440spe_adma_desc_slot *ppc440spe_dma01_prep_mult(
2086 		struct ppc440spe_adma_chan *ppc440spe_chan,
2087 		dma_addr_t *dst, int dst_cnt, dma_addr_t *src, int src_cnt,
2088 		const unsigned char *scf, size_t len, unsigned long flags)
2089 {
2090 	struct ppc440spe_adma_desc_slot *sw_desc = NULL;
2091 	unsigned long op = 0;
2092 	int slot_cnt;
2093 
2094 	set_bit(PPC440SPE_DESC_WXOR, &op);
2095 	slot_cnt = 2;
2096 
2097 	spin_lock_bh(&ppc440spe_chan->lock);
2098 
2099 	/* use WXOR, each descriptor occupies one slot */
2100 	sw_desc = ppc440spe_adma_alloc_slots(ppc440spe_chan, slot_cnt, 1);
2101 	if (sw_desc) {
2102 		struct ppc440spe_adma_chan *chan;
2103 		struct ppc440spe_adma_desc_slot *iter;
2104 		struct dma_cdb *hw_desc;
2105 
2106 		chan = to_ppc440spe_adma_chan(sw_desc->async_tx.chan);
2107 		set_bits(op, &sw_desc->flags);
2108 		sw_desc->src_cnt = src_cnt;
2109 		sw_desc->dst_cnt = dst_cnt;
2110 		/* First descriptor, zero data in the destination and copy it
2111 		 * to q page using MULTICAST transfer.
2112 		 */
2113 		iter = list_first_entry(&sw_desc->group_list,
2114 					struct ppc440spe_adma_desc_slot,
2115 					chain_node);
2116 		memset(iter->hw_desc, 0, sizeof(struct dma_cdb));
2117 		/* set 'next' pointer */
2118 		iter->hw_next = list_entry(iter->chain_node.next,
2119 					   struct ppc440spe_adma_desc_slot,
2120 					   chain_node);
2121 		clear_bit(PPC440SPE_DESC_INT, &iter->flags);
2122 		hw_desc = iter->hw_desc;
2123 		hw_desc->opc = DMA_CDB_OPC_MULTICAST;
2124 
2125 		ppc440spe_desc_set_dest_addr(iter, chan,
2126 					     DMA_CUED_XOR_BASE, dst[0], 0);
2127 		ppc440spe_desc_set_dest_addr(iter, chan, 0, dst[1], 1);
2128 		ppc440spe_desc_set_src_addr(iter, chan, 0, DMA_CUED_XOR_HB,
2129 					    src[0]);
2130 		ppc440spe_desc_set_byte_count(iter, ppc440spe_chan, len);
2131 		iter->unmap_len = len;
2132 
2133 		/*
2134 		 * Second descriptor, multiply data from the q page
2135 		 * and store the result in real destination.
2136 		 */
2137 		iter = list_first_entry(&iter->chain_node,
2138 					struct ppc440spe_adma_desc_slot,
2139 					chain_node);
2140 		memset(iter->hw_desc, 0, sizeof(struct dma_cdb));
2141 		iter->hw_next = NULL;
2142 		if (flags & DMA_PREP_INTERRUPT)
2143 			set_bit(PPC440SPE_DESC_INT, &iter->flags);
2144 		else
2145 			clear_bit(PPC440SPE_DESC_INT, &iter->flags);
2146 
2147 		hw_desc = iter->hw_desc;
2148 		hw_desc->opc = DMA_CDB_OPC_MV_SG1_SG2;
2149 		ppc440spe_desc_set_src_addr(iter, chan, 0,
2150 					    DMA_CUED_XOR_HB, dst[1]);
2151 		ppc440spe_desc_set_dest_addr(iter, chan,
2152 					     DMA_CUED_XOR_BASE, dst[0], 0);
2153 
2154 		ppc440spe_desc_set_src_mult(iter, chan, DMA_CUED_MULT1_OFF,
2155 					    DMA_CDB_SG_DST1, scf[0]);
2156 		ppc440spe_desc_set_byte_count(iter, ppc440spe_chan, len);
2157 		iter->unmap_len = len;
2158 		sw_desc->async_tx.flags = flags;
2159 	}
2160 
2161 	spin_unlock_bh(&ppc440spe_chan->lock);
2162 
2163 	return sw_desc;
2164 }
2165 
2166 /**
2167  * ppc440spe_dma01_prep_sum_product -
2168  * Dx = A*(P+Pxy) + B*(Q+Qxy) operation where destination is also
2169  * the source.
2170  */
2171 static struct ppc440spe_adma_desc_slot *ppc440spe_dma01_prep_sum_product(
2172 		struct ppc440spe_adma_chan *ppc440spe_chan,
2173 		dma_addr_t *dst, dma_addr_t *src, int src_cnt,
2174 		const unsigned char *scf, size_t len, unsigned long flags)
2175 {
2176 	struct ppc440spe_adma_desc_slot *sw_desc = NULL;
2177 	unsigned long op = 0;
2178 	int slot_cnt;
2179 
2180 	set_bit(PPC440SPE_DESC_WXOR, &op);
2181 	slot_cnt = 3;
2182 
2183 	spin_lock_bh(&ppc440spe_chan->lock);
2184 
2185 	/* WXOR, each descriptor occupies one slot */
2186 	sw_desc = ppc440spe_adma_alloc_slots(ppc440spe_chan, slot_cnt, 1);
2187 	if (sw_desc) {
2188 		struct ppc440spe_adma_chan *chan;
2189 		struct ppc440spe_adma_desc_slot *iter;
2190 		struct dma_cdb *hw_desc;
2191 
2192 		chan = to_ppc440spe_adma_chan(sw_desc->async_tx.chan);
2193 		set_bits(op, &sw_desc->flags);
2194 		sw_desc->src_cnt = src_cnt;
2195 		sw_desc->dst_cnt = 1;
2196 		/* 1st descriptor, src[1] data to q page and zero destination */
2197 		iter = list_first_entry(&sw_desc->group_list,
2198 					struct ppc440spe_adma_desc_slot,
2199 					chain_node);
2200 		memset(iter->hw_desc, 0, sizeof(struct dma_cdb));
2201 		iter->hw_next = list_entry(iter->chain_node.next,
2202 					   struct ppc440spe_adma_desc_slot,
2203 					   chain_node);
2204 		clear_bit(PPC440SPE_DESC_INT, &iter->flags);
2205 		hw_desc = iter->hw_desc;
2206 		hw_desc->opc = DMA_CDB_OPC_MULTICAST;
2207 
2208 		ppc440spe_desc_set_dest_addr(iter, chan, DMA_CUED_XOR_BASE,
2209 					     *dst, 0);
2210 		ppc440spe_desc_set_dest_addr(iter, chan, 0,
2211 					     ppc440spe_chan->qdest, 1);
2212 		ppc440spe_desc_set_src_addr(iter, chan, 0, DMA_CUED_XOR_HB,
2213 					    src[1]);
2214 		ppc440spe_desc_set_byte_count(iter, ppc440spe_chan, len);
2215 		iter->unmap_len = len;
2216 
2217 		/* 2nd descriptor, multiply src[1] data and store the
2218 		 * result in destination */
2219 		iter = list_first_entry(&iter->chain_node,
2220 					struct ppc440spe_adma_desc_slot,
2221 					chain_node);
2222 		memset(iter->hw_desc, 0, sizeof(struct dma_cdb));
2223 		/* set 'next' pointer */
2224 		iter->hw_next = list_entry(iter->chain_node.next,
2225 					   struct ppc440spe_adma_desc_slot,
2226 					   chain_node);
2227 		if (flags & DMA_PREP_INTERRUPT)
2228 			set_bit(PPC440SPE_DESC_INT, &iter->flags);
2229 		else
2230 			clear_bit(PPC440SPE_DESC_INT, &iter->flags);
2231 
2232 		hw_desc = iter->hw_desc;
2233 		hw_desc->opc = DMA_CDB_OPC_MV_SG1_SG2;
2234 		ppc440spe_desc_set_src_addr(iter, chan, 0, DMA_CUED_XOR_HB,
2235 					    ppc440spe_chan->qdest);
2236 		ppc440spe_desc_set_dest_addr(iter, chan, DMA_CUED_XOR_BASE,
2237 					     *dst, 0);
2238 		ppc440spe_desc_set_src_mult(iter, chan,	DMA_CUED_MULT1_OFF,
2239 					    DMA_CDB_SG_DST1, scf[1]);
2240 		ppc440spe_desc_set_byte_count(iter, ppc440spe_chan, len);
2241 		iter->unmap_len = len;
2242 
2243 		/*
2244 		 * 3rd descriptor, multiply src[0] data and xor it
2245 		 * with destination
2246 		 */
2247 		iter = list_first_entry(&iter->chain_node,
2248 					struct ppc440spe_adma_desc_slot,
2249 					chain_node);
2250 		memset(iter->hw_desc, 0, sizeof(struct dma_cdb));
2251 		iter->hw_next = NULL;
2252 		if (flags & DMA_PREP_INTERRUPT)
2253 			set_bit(PPC440SPE_DESC_INT, &iter->flags);
2254 		else
2255 			clear_bit(PPC440SPE_DESC_INT, &iter->flags);
2256 
2257 		hw_desc = iter->hw_desc;
2258 		hw_desc->opc = DMA_CDB_OPC_MV_SG1_SG2;
2259 		ppc440spe_desc_set_src_addr(iter, chan, 0, DMA_CUED_XOR_HB,
2260 					    src[0]);
2261 		ppc440spe_desc_set_dest_addr(iter, chan, DMA_CUED_XOR_BASE,
2262 					     *dst, 0);
2263 		ppc440spe_desc_set_src_mult(iter, chan, DMA_CUED_MULT1_OFF,
2264 					    DMA_CDB_SG_DST1, scf[0]);
2265 		ppc440spe_desc_set_byte_count(iter, ppc440spe_chan, len);
2266 		iter->unmap_len = len;
2267 		sw_desc->async_tx.flags = flags;
2268 	}
2269 
2270 	spin_unlock_bh(&ppc440spe_chan->lock);
2271 
2272 	return sw_desc;
2273 }
2274 
2275 static struct ppc440spe_adma_desc_slot *ppc440spe_dma01_prep_pq(
2276 		struct ppc440spe_adma_chan *ppc440spe_chan,
2277 		dma_addr_t *dst, int dst_cnt, dma_addr_t *src, int src_cnt,
2278 		const unsigned char *scf, size_t len, unsigned long flags)
2279 {
2280 	int slot_cnt;
2281 	struct ppc440spe_adma_desc_slot *sw_desc = NULL, *iter;
2282 	unsigned long op = 0;
2283 	unsigned char mult = 1;
2284 
2285 	pr_debug("%s: dst_cnt %d, src_cnt %d, len %d\n",
2286 		 __func__, dst_cnt, src_cnt, len);
2287 	/*  select operations WXOR/RXOR depending on the
2288 	 * source addresses of operators and the number
2289 	 * of destinations (RXOR support only Q-parity calculations)
2290 	 */
2291 	set_bit(PPC440SPE_DESC_WXOR, &op);
2292 	if (!test_and_set_bit(PPC440SPE_RXOR_RUN, &ppc440spe_rxor_state)) {
2293 		/* no active RXOR;
2294 		 * do RXOR if:
2295 		 * - there are more than 1 source,
2296 		 * - len is aligned on 512-byte boundary,
2297 		 * - source addresses fit to one of 4 possible regions.
2298 		 */
2299 		if (src_cnt > 1 &&
2300 		    !(len & MQ0_CF2H_RXOR_BS_MASK) &&
2301 		    (src[0] + len) == src[1]) {
2302 			/* may do RXOR R1 R2 */
2303 			set_bit(PPC440SPE_DESC_RXOR, &op);
2304 			if (src_cnt != 2) {
2305 				/* may try to enhance region of RXOR */
2306 				if ((src[1] + len) == src[2]) {
2307 					/* do RXOR R1 R2 R3 */
2308 					set_bit(PPC440SPE_DESC_RXOR123,
2309 						&op);
2310 				} else if ((src[1] + len * 2) == src[2]) {
2311 					/* do RXOR R1 R2 R4 */
2312 					set_bit(PPC440SPE_DESC_RXOR124, &op);
2313 				} else if ((src[1] + len * 3) == src[2]) {
2314 					/* do RXOR R1 R2 R5 */
2315 					set_bit(PPC440SPE_DESC_RXOR125,
2316 						&op);
2317 				} else {
2318 					/* do RXOR R1 R2 */
2319 					set_bit(PPC440SPE_DESC_RXOR12,
2320 						&op);
2321 				}
2322 			} else {
2323 				/* do RXOR R1 R2 */
2324 				set_bit(PPC440SPE_DESC_RXOR12, &op);
2325 			}
2326 		}
2327 
2328 		if (!test_bit(PPC440SPE_DESC_RXOR, &op)) {
2329 			/* can not do this operation with RXOR */
2330 			clear_bit(PPC440SPE_RXOR_RUN,
2331 				&ppc440spe_rxor_state);
2332 		} else {
2333 			/* can do; set block size right now */
2334 			ppc440spe_desc_set_rxor_block_size(len);
2335 		}
2336 	}
2337 
2338 	/* Number of necessary slots depends on operation type selected */
2339 	if (!test_bit(PPC440SPE_DESC_RXOR, &op)) {
2340 		/*  This is a WXOR only chain. Need descriptors for each
2341 		 * source to GF-XOR them with WXOR, and need descriptors
2342 		 * for each destination to zero them with WXOR
2343 		 */
2344 		slot_cnt = src_cnt;
2345 
2346 		if (flags & DMA_PREP_ZERO_P) {
2347 			slot_cnt++;
2348 			set_bit(PPC440SPE_ZERO_P, &op);
2349 		}
2350 		if (flags & DMA_PREP_ZERO_Q) {
2351 			slot_cnt++;
2352 			set_bit(PPC440SPE_ZERO_Q, &op);
2353 		}
2354 	} else {
2355 		/*  Need 1/2 descriptor for RXOR operation, and
2356 		 * need (src_cnt - (2 or 3)) for WXOR of sources
2357 		 * remained (if any)
2358 		 */
2359 		slot_cnt = dst_cnt;
2360 
2361 		if (flags & DMA_PREP_ZERO_P)
2362 			set_bit(PPC440SPE_ZERO_P, &op);
2363 		if (flags & DMA_PREP_ZERO_Q)
2364 			set_bit(PPC440SPE_ZERO_Q, &op);
2365 
2366 		if (test_bit(PPC440SPE_DESC_RXOR12, &op))
2367 			slot_cnt += src_cnt - 2;
2368 		else
2369 			slot_cnt += src_cnt - 3;
2370 
2371 		/*  Thus we have either RXOR only chain or
2372 		 * mixed RXOR/WXOR
2373 		 */
2374 		if (slot_cnt == dst_cnt)
2375 			/* RXOR only chain */
2376 			clear_bit(PPC440SPE_DESC_WXOR, &op);
2377 	}
2378 
2379 	spin_lock_bh(&ppc440spe_chan->lock);
2380 	/* for both RXOR/WXOR each descriptor occupies one slot */
2381 	sw_desc = ppc440spe_adma_alloc_slots(ppc440spe_chan, slot_cnt, 1);
2382 	if (sw_desc) {
2383 		ppc440spe_desc_init_dma01pq(sw_desc, dst_cnt, src_cnt,
2384 				flags, op);
2385 
2386 		/* setup dst/src/mult */
2387 		pr_debug("%s: set dst descriptor 0, 1: 0x%016llx, 0x%016llx\n",
2388 			 __func__, dst[0], dst[1]);
2389 		ppc440spe_adma_pq_set_dest(sw_desc, dst, flags);
2390 		while (src_cnt--) {
2391 			ppc440spe_adma_pq_set_src(sw_desc, src[src_cnt],
2392 						  src_cnt);
2393 
2394 			/* NOTE: "Multi = 0 is equivalent to = 1" as it
2395 			 * stated in 440SPSPe_RAID6_Addendum_UM_1_17.pdf
2396 			 * doesn't work for RXOR with DMA0/1! Instead, multi=0
2397 			 * leads to zeroing source data after RXOR.
2398 			 * So, for P case set-up mult=1 explicitly.
2399 			 */
2400 			if (!(flags & DMA_PREP_PQ_DISABLE_Q))
2401 				mult = scf[src_cnt];
2402 			ppc440spe_adma_pq_set_src_mult(sw_desc,
2403 				mult, src_cnt,  dst_cnt - 1);
2404 		}
2405 
2406 		/* Setup byte count foreach slot just allocated */
2407 		sw_desc->async_tx.flags = flags;
2408 		list_for_each_entry(iter, &sw_desc->group_list,
2409 				chain_node) {
2410 			ppc440spe_desc_set_byte_count(iter,
2411 				ppc440spe_chan, len);
2412 			iter->unmap_len = len;
2413 		}
2414 	}
2415 	spin_unlock_bh(&ppc440spe_chan->lock);
2416 
2417 	return sw_desc;
2418 }
2419 
2420 static struct ppc440spe_adma_desc_slot *ppc440spe_dma2_prep_pq(
2421 		struct ppc440spe_adma_chan *ppc440spe_chan,
2422 		dma_addr_t *dst, int dst_cnt, dma_addr_t *src, int src_cnt,
2423 		const unsigned char *scf, size_t len, unsigned long flags)
2424 {
2425 	int slot_cnt, descs_per_op;
2426 	struct ppc440spe_adma_desc_slot *sw_desc = NULL, *iter;
2427 	unsigned long op = 0;
2428 	unsigned char mult = 1;
2429 
2430 	BUG_ON(!dst_cnt);
2431 	/*pr_debug("%s: dst_cnt %d, src_cnt %d, len %d\n",
2432 		 __func__, dst_cnt, src_cnt, len);*/
2433 
2434 	spin_lock_bh(&ppc440spe_chan->lock);
2435 	descs_per_op = ppc440spe_dma2_pq_slot_count(src, src_cnt, len);
2436 	if (descs_per_op < 0) {
2437 		spin_unlock_bh(&ppc440spe_chan->lock);
2438 		return NULL;
2439 	}
2440 
2441 	/* depending on number of sources we have 1 or 2 RXOR chains */
2442 	slot_cnt = descs_per_op * dst_cnt;
2443 
2444 	sw_desc = ppc440spe_adma_alloc_slots(ppc440spe_chan, slot_cnt, 1);
2445 	if (sw_desc) {
2446 		op = slot_cnt;
2447 		sw_desc->async_tx.flags = flags;
2448 		list_for_each_entry(iter, &sw_desc->group_list, chain_node) {
2449 			ppc440spe_desc_init_dma2pq(iter, dst_cnt, src_cnt,
2450 				--op ? 0 : flags);
2451 			ppc440spe_desc_set_byte_count(iter, ppc440spe_chan,
2452 				len);
2453 			iter->unmap_len = len;
2454 
2455 			ppc440spe_init_rxor_cursor(&(iter->rxor_cursor));
2456 			iter->rxor_cursor.len = len;
2457 			iter->descs_per_op = descs_per_op;
2458 		}
2459 		op = 0;
2460 		list_for_each_entry(iter, &sw_desc->group_list, chain_node) {
2461 			op++;
2462 			if (op % descs_per_op == 0)
2463 				ppc440spe_adma_init_dma2rxor_slot(iter, src,
2464 								  src_cnt);
2465 			if (likely(!list_is_last(&iter->chain_node,
2466 						 &sw_desc->group_list))) {
2467 				/* set 'next' pointer */
2468 				iter->hw_next =
2469 					list_entry(iter->chain_node.next,
2470 						struct ppc440spe_adma_desc_slot,
2471 						chain_node);
2472 				ppc440spe_xor_set_link(iter, iter->hw_next);
2473 			} else {
2474 				/* this is the last descriptor. */
2475 				iter->hw_next = NULL;
2476 			}
2477 		}
2478 
2479 		/* fixup head descriptor */
2480 		sw_desc->dst_cnt = dst_cnt;
2481 		if (flags & DMA_PREP_ZERO_P)
2482 			set_bit(PPC440SPE_ZERO_P, &sw_desc->flags);
2483 		if (flags & DMA_PREP_ZERO_Q)
2484 			set_bit(PPC440SPE_ZERO_Q, &sw_desc->flags);
2485 
2486 		/* setup dst/src/mult */
2487 		ppc440spe_adma_pq_set_dest(sw_desc, dst, flags);
2488 
2489 		while (src_cnt--) {
2490 			/* handle descriptors (if dst_cnt == 2) inside
2491 			 * the ppc440spe_adma_pq_set_srcxxx() functions
2492 			 */
2493 			ppc440spe_adma_pq_set_src(sw_desc, src[src_cnt],
2494 						  src_cnt);
2495 			if (!(flags & DMA_PREP_PQ_DISABLE_Q))
2496 				mult = scf[src_cnt];
2497 			ppc440spe_adma_pq_set_src_mult(sw_desc,
2498 					mult, src_cnt, dst_cnt - 1);
2499 		}
2500 	}
2501 	spin_unlock_bh(&ppc440spe_chan->lock);
2502 	ppc440spe_desc_set_rxor_block_size(len);
2503 	return sw_desc;
2504 }
2505 
2506 /**
2507  * ppc440spe_adma_prep_dma_pq - prepare CDB (group) for a GF-XOR operation
2508  */
2509 static struct dma_async_tx_descriptor *ppc440spe_adma_prep_dma_pq(
2510 		struct dma_chan *chan, dma_addr_t *dst, dma_addr_t *src,
2511 		unsigned int src_cnt, const unsigned char *scf,
2512 		size_t len, unsigned long flags)
2513 {
2514 	struct ppc440spe_adma_chan *ppc440spe_chan;
2515 	struct ppc440spe_adma_desc_slot *sw_desc = NULL;
2516 	int dst_cnt = 0;
2517 
2518 	ppc440spe_chan = to_ppc440spe_adma_chan(chan);
2519 
2520 	ADMA_LL_DBG(prep_dma_pq_dbg(ppc440spe_chan->device->id,
2521 				    dst, src, src_cnt));
2522 	BUG_ON(!len);
2523 	BUG_ON(len > PPC440SPE_ADMA_XOR_MAX_BYTE_COUNT);
2524 	BUG_ON(!src_cnt);
2525 
2526 	if (src_cnt == 1 && dst[1] == src[0]) {
2527 		dma_addr_t dest[2];
2528 
2529 		/* dst[1] is real destination (Q) */
2530 		dest[0] = dst[1];
2531 		/* this is the page to multicast source data to */
2532 		dest[1] = ppc440spe_chan->qdest;
2533 		sw_desc = ppc440spe_dma01_prep_mult(ppc440spe_chan,
2534 				dest, 2, src, src_cnt, scf, len, flags);
2535 		return sw_desc ? &sw_desc->async_tx : NULL;
2536 	}
2537 
2538 	if (src_cnt == 2 && dst[1] == src[1]) {
2539 		sw_desc = ppc440spe_dma01_prep_sum_product(ppc440spe_chan,
2540 					&dst[1], src, 2, scf, len, flags);
2541 		return sw_desc ? &sw_desc->async_tx : NULL;
2542 	}
2543 
2544 	if (!(flags & DMA_PREP_PQ_DISABLE_P)) {
2545 		BUG_ON(!dst[0]);
2546 		dst_cnt++;
2547 		flags |= DMA_PREP_ZERO_P;
2548 	}
2549 
2550 	if (!(flags & DMA_PREP_PQ_DISABLE_Q)) {
2551 		BUG_ON(!dst[1]);
2552 		dst_cnt++;
2553 		flags |= DMA_PREP_ZERO_Q;
2554 	}
2555 
2556 	BUG_ON(!dst_cnt);
2557 
2558 	dev_dbg(ppc440spe_chan->device->common.dev,
2559 		"ppc440spe adma%d: %s src_cnt: %d len: %u int_en: %d\n",
2560 		ppc440spe_chan->device->id, __func__, src_cnt, len,
2561 		flags & DMA_PREP_INTERRUPT ? 1 : 0);
2562 
2563 	switch (ppc440spe_chan->device->id) {
2564 	case PPC440SPE_DMA0_ID:
2565 	case PPC440SPE_DMA1_ID:
2566 		sw_desc = ppc440spe_dma01_prep_pq(ppc440spe_chan,
2567 				dst, dst_cnt, src, src_cnt, scf,
2568 				len, flags);
2569 		break;
2570 
2571 	case PPC440SPE_XOR_ID:
2572 		sw_desc = ppc440spe_dma2_prep_pq(ppc440spe_chan,
2573 				dst, dst_cnt, src, src_cnt, scf,
2574 				len, flags);
2575 		break;
2576 	}
2577 
2578 	return sw_desc ? &sw_desc->async_tx : NULL;
2579 }
2580 
2581 /**
2582  * ppc440spe_adma_prep_dma_pqzero_sum - prepare CDB group for
2583  * a PQ_ZERO_SUM operation
2584  */
2585 static struct dma_async_tx_descriptor *ppc440spe_adma_prep_dma_pqzero_sum(
2586 		struct dma_chan *chan, dma_addr_t *pq, dma_addr_t *src,
2587 		unsigned int src_cnt, const unsigned char *scf, size_t len,
2588 		enum sum_check_flags *pqres, unsigned long flags)
2589 {
2590 	struct ppc440spe_adma_chan *ppc440spe_chan;
2591 	struct ppc440spe_adma_desc_slot *sw_desc, *iter;
2592 	dma_addr_t pdest, qdest;
2593 	int slot_cnt, slots_per_op, idst, dst_cnt;
2594 
2595 	ppc440spe_chan = to_ppc440spe_adma_chan(chan);
2596 
2597 	if (flags & DMA_PREP_PQ_DISABLE_P)
2598 		pdest = 0;
2599 	else
2600 		pdest = pq[0];
2601 
2602 	if (flags & DMA_PREP_PQ_DISABLE_Q)
2603 		qdest = 0;
2604 	else
2605 		qdest = pq[1];
2606 
2607 	ADMA_LL_DBG(prep_dma_pqzero_sum_dbg(ppc440spe_chan->device->id,
2608 					    src, src_cnt, scf));
2609 
2610 	/* Always use WXOR for P/Q calculations (two destinations).
2611 	 * Need 1 or 2 extra slots to verify results are zero.
2612 	 */
2613 	idst = dst_cnt = (pdest && qdest) ? 2 : 1;
2614 
2615 	/* One additional slot per destination to clone P/Q
2616 	 * before calculation (we have to preserve destinations).
2617 	 */
2618 	slot_cnt = src_cnt + dst_cnt * 2;
2619 	slots_per_op = 1;
2620 
2621 	spin_lock_bh(&ppc440spe_chan->lock);
2622 	sw_desc = ppc440spe_adma_alloc_slots(ppc440spe_chan, slot_cnt,
2623 					     slots_per_op);
2624 	if (sw_desc) {
2625 		ppc440spe_desc_init_dma01pqzero_sum(sw_desc, dst_cnt, src_cnt);
2626 
2627 		/* Setup byte count for each slot just allocated */
2628 		sw_desc->async_tx.flags = flags;
2629 		list_for_each_entry(iter, &sw_desc->group_list, chain_node) {
2630 			ppc440spe_desc_set_byte_count(iter, ppc440spe_chan,
2631 						      len);
2632 			iter->unmap_len = len;
2633 		}
2634 
2635 		if (pdest) {
2636 			struct dma_cdb *hw_desc;
2637 			struct ppc440spe_adma_chan *chan;
2638 
2639 			iter = sw_desc->group_head;
2640 			chan = to_ppc440spe_adma_chan(iter->async_tx.chan);
2641 			memset(iter->hw_desc, 0, sizeof(struct dma_cdb));
2642 			iter->hw_next = list_entry(iter->chain_node.next,
2643 						struct ppc440spe_adma_desc_slot,
2644 						chain_node);
2645 			hw_desc = iter->hw_desc;
2646 			hw_desc->opc = DMA_CDB_OPC_MV_SG1_SG2;
2647 			iter->src_cnt = 0;
2648 			iter->dst_cnt = 0;
2649 			ppc440spe_desc_set_dest_addr(iter, chan, 0,
2650 						     ppc440spe_chan->pdest, 0);
2651 			ppc440spe_desc_set_src_addr(iter, chan, 0, 0, pdest);
2652 			ppc440spe_desc_set_byte_count(iter, ppc440spe_chan,
2653 						      len);
2654 			iter->unmap_len = 0;
2655 			/* override pdest to preserve original P */
2656 			pdest = ppc440spe_chan->pdest;
2657 		}
2658 		if (qdest) {
2659 			struct dma_cdb *hw_desc;
2660 			struct ppc440spe_adma_chan *chan;
2661 
2662 			iter = list_first_entry(&sw_desc->group_list,
2663 						struct ppc440spe_adma_desc_slot,
2664 						chain_node);
2665 			chan = to_ppc440spe_adma_chan(iter->async_tx.chan);
2666 
2667 			if (pdest) {
2668 				iter = list_entry(iter->chain_node.next,
2669 						struct ppc440spe_adma_desc_slot,
2670 						chain_node);
2671 			}
2672 
2673 			memset(iter->hw_desc, 0, sizeof(struct dma_cdb));
2674 			iter->hw_next = list_entry(iter->chain_node.next,
2675 						struct ppc440spe_adma_desc_slot,
2676 						chain_node);
2677 			hw_desc = iter->hw_desc;
2678 			hw_desc->opc = DMA_CDB_OPC_MV_SG1_SG2;
2679 			iter->src_cnt = 0;
2680 			iter->dst_cnt = 0;
2681 			ppc440spe_desc_set_dest_addr(iter, chan, 0,
2682 						     ppc440spe_chan->qdest, 0);
2683 			ppc440spe_desc_set_src_addr(iter, chan, 0, 0, qdest);
2684 			ppc440spe_desc_set_byte_count(iter, ppc440spe_chan,
2685 						      len);
2686 			iter->unmap_len = 0;
2687 			/* override qdest to preserve original Q */
2688 			qdest = ppc440spe_chan->qdest;
2689 		}
2690 
2691 		/* Setup destinations for P/Q ops */
2692 		ppc440spe_adma_pqzero_sum_set_dest(sw_desc, pdest, qdest);
2693 
2694 		/* Setup zero QWORDs into DCHECK CDBs */
2695 		idst = dst_cnt;
2696 		list_for_each_entry_reverse(iter, &sw_desc->group_list,
2697 					    chain_node) {
2698 			/*
2699 			 * The last CDB corresponds to Q-parity check,
2700 			 * the one before last CDB corresponds
2701 			 * P-parity check
2702 			 */
2703 			if (idst == DMA_DEST_MAX_NUM) {
2704 				if (idst == dst_cnt) {
2705 					set_bit(PPC440SPE_DESC_QCHECK,
2706 						&iter->flags);
2707 				} else {
2708 					set_bit(PPC440SPE_DESC_PCHECK,
2709 						&iter->flags);
2710 				}
2711 			} else {
2712 				if (qdest) {
2713 					set_bit(PPC440SPE_DESC_QCHECK,
2714 						&iter->flags);
2715 				} else {
2716 					set_bit(PPC440SPE_DESC_PCHECK,
2717 						&iter->flags);
2718 				}
2719 			}
2720 			iter->xor_check_result = pqres;
2721 
2722 			/*
2723 			 * set it to zero, if check fail then result will
2724 			 * be updated
2725 			 */
2726 			*iter->xor_check_result = 0;
2727 			ppc440spe_desc_set_dcheck(iter, ppc440spe_chan,
2728 				ppc440spe_qword);
2729 
2730 			if (!(--dst_cnt))
2731 				break;
2732 		}
2733 
2734 		/* Setup sources and mults for P/Q ops */
2735 		list_for_each_entry_continue_reverse(iter, &sw_desc->group_list,
2736 						     chain_node) {
2737 			struct ppc440spe_adma_chan *chan;
2738 			u32 mult_dst;
2739 
2740 			chan = to_ppc440spe_adma_chan(iter->async_tx.chan);
2741 			ppc440spe_desc_set_src_addr(iter, chan, 0,
2742 						    DMA_CUED_XOR_HB,
2743 						    src[src_cnt - 1]);
2744 			if (qdest) {
2745 				mult_dst = (dst_cnt - 1) ? DMA_CDB_SG_DST2 :
2746 							   DMA_CDB_SG_DST1;
2747 				ppc440spe_desc_set_src_mult(iter, chan,
2748 							    DMA_CUED_MULT1_OFF,
2749 							    mult_dst,
2750 							    scf[src_cnt - 1]);
2751 			}
2752 			if (!(--src_cnt))
2753 				break;
2754 		}
2755 	}
2756 	spin_unlock_bh(&ppc440spe_chan->lock);
2757 	return sw_desc ? &sw_desc->async_tx : NULL;
2758 }
2759 
2760 /**
2761  * ppc440spe_adma_prep_dma_xor_zero_sum - prepare CDB group for
2762  * XOR ZERO_SUM operation
2763  */
2764 static struct dma_async_tx_descriptor *ppc440spe_adma_prep_dma_xor_zero_sum(
2765 		struct dma_chan *chan, dma_addr_t *src, unsigned int src_cnt,
2766 		size_t len, enum sum_check_flags *result, unsigned long flags)
2767 {
2768 	struct dma_async_tx_descriptor *tx;
2769 	dma_addr_t pq[2];
2770 
2771 	/* validate P, disable Q */
2772 	pq[0] = src[0];
2773 	pq[1] = 0;
2774 	flags |= DMA_PREP_PQ_DISABLE_Q;
2775 
2776 	tx = ppc440spe_adma_prep_dma_pqzero_sum(chan, pq, &src[1],
2777 						src_cnt - 1, 0, len,
2778 						result, flags);
2779 	return tx;
2780 }
2781 
2782 /**
2783  * ppc440spe_adma_set_dest - set destination address into descriptor
2784  */
2785 static void ppc440spe_adma_set_dest(struct ppc440spe_adma_desc_slot *sw_desc,
2786 		dma_addr_t addr, int index)
2787 {
2788 	struct ppc440spe_adma_chan *chan;
2789 
2790 	BUG_ON(index >= sw_desc->dst_cnt);
2791 
2792 	chan = to_ppc440spe_adma_chan(sw_desc->async_tx.chan);
2793 
2794 	switch (chan->device->id) {
2795 	case PPC440SPE_DMA0_ID:
2796 	case PPC440SPE_DMA1_ID:
2797 		/* to do: support transfers lengths >
2798 		 * PPC440SPE_ADMA_DMA/XOR_MAX_BYTE_COUNT
2799 		 */
2800 		ppc440spe_desc_set_dest_addr(sw_desc->group_head,
2801 			chan, 0, addr, index);
2802 		break;
2803 	case PPC440SPE_XOR_ID:
2804 		sw_desc = ppc440spe_get_group_entry(sw_desc, index);
2805 		ppc440spe_desc_set_dest_addr(sw_desc,
2806 			chan, 0, addr, index);
2807 		break;
2808 	}
2809 }
2810 
2811 static void ppc440spe_adma_pq_zero_op(struct ppc440spe_adma_desc_slot *iter,
2812 		struct ppc440spe_adma_chan *chan, dma_addr_t addr)
2813 {
2814 	/*  To clear destinations update the descriptor
2815 	 * (P or Q depending on index) as follows:
2816 	 * addr is destination (0 corresponds to SG2):
2817 	 */
2818 	ppc440spe_desc_set_dest_addr(iter, chan, DMA_CUED_XOR_BASE, addr, 0);
2819 
2820 	/* ... and the addr is source: */
2821 	ppc440spe_desc_set_src_addr(iter, chan, 0, DMA_CUED_XOR_HB, addr);
2822 
2823 	/* addr is always SG2 then the mult is always DST1 */
2824 	ppc440spe_desc_set_src_mult(iter, chan, DMA_CUED_MULT1_OFF,
2825 				    DMA_CDB_SG_DST1, 1);
2826 }
2827 
2828 /**
2829  * ppc440spe_adma_pq_set_dest - set destination address into descriptor
2830  * for the PQXOR operation
2831  */
2832 static void ppc440spe_adma_pq_set_dest(struct ppc440spe_adma_desc_slot *sw_desc,
2833 		dma_addr_t *addrs, unsigned long flags)
2834 {
2835 	struct ppc440spe_adma_desc_slot *iter;
2836 	struct ppc440spe_adma_chan *chan;
2837 	dma_addr_t paddr, qaddr;
2838 	dma_addr_t addr = 0, ppath, qpath;
2839 	int index = 0, i;
2840 
2841 	chan = to_ppc440spe_adma_chan(sw_desc->async_tx.chan);
2842 
2843 	if (flags & DMA_PREP_PQ_DISABLE_P)
2844 		paddr = 0;
2845 	else
2846 		paddr = addrs[0];
2847 
2848 	if (flags & DMA_PREP_PQ_DISABLE_Q)
2849 		qaddr = 0;
2850 	else
2851 		qaddr = addrs[1];
2852 
2853 	if (!paddr || !qaddr)
2854 		addr = paddr ? paddr : qaddr;
2855 
2856 	switch (chan->device->id) {
2857 	case PPC440SPE_DMA0_ID:
2858 	case PPC440SPE_DMA1_ID:
2859 		/* walk through the WXOR source list and set P/Q-destinations
2860 		 * for each slot:
2861 		 */
2862 		if (!test_bit(PPC440SPE_DESC_RXOR, &sw_desc->flags)) {
2863 			/* This is WXOR-only chain; may have 1/2 zero descs */
2864 			if (test_bit(PPC440SPE_ZERO_P, &sw_desc->flags))
2865 				index++;
2866 			if (test_bit(PPC440SPE_ZERO_Q, &sw_desc->flags))
2867 				index++;
2868 
2869 			iter = ppc440spe_get_group_entry(sw_desc, index);
2870 			if (addr) {
2871 				/* one destination */
2872 				list_for_each_entry_from(iter,
2873 					&sw_desc->group_list, chain_node)
2874 					ppc440spe_desc_set_dest_addr(iter, chan,
2875 						DMA_CUED_XOR_BASE, addr, 0);
2876 			} else {
2877 				/* two destinations */
2878 				list_for_each_entry_from(iter,
2879 					&sw_desc->group_list, chain_node) {
2880 					ppc440spe_desc_set_dest_addr(iter, chan,
2881 						DMA_CUED_XOR_BASE, paddr, 0);
2882 					ppc440spe_desc_set_dest_addr(iter, chan,
2883 						DMA_CUED_XOR_BASE, qaddr, 1);
2884 				}
2885 			}
2886 
2887 			if (index) {
2888 				/*  To clear destinations update the descriptor
2889 				 * (1st,2nd, or both depending on flags)
2890 				 */
2891 				index = 0;
2892 				if (test_bit(PPC440SPE_ZERO_P,
2893 						&sw_desc->flags)) {
2894 					iter = ppc440spe_get_group_entry(
2895 							sw_desc, index++);
2896 					ppc440spe_adma_pq_zero_op(iter, chan,
2897 							paddr);
2898 				}
2899 
2900 				if (test_bit(PPC440SPE_ZERO_Q,
2901 						&sw_desc->flags)) {
2902 					iter = ppc440spe_get_group_entry(
2903 							sw_desc, index++);
2904 					ppc440spe_adma_pq_zero_op(iter, chan,
2905 							qaddr);
2906 				}
2907 
2908 				return;
2909 			}
2910 		} else {
2911 			/* This is RXOR-only or RXOR/WXOR mixed chain */
2912 
2913 			/* If we want to include destination into calculations,
2914 			 * then make dest addresses cued with mult=1 (XOR).
2915 			 */
2916 			ppath = test_bit(PPC440SPE_ZERO_P, &sw_desc->flags) ?
2917 					DMA_CUED_XOR_HB :
2918 					DMA_CUED_XOR_BASE |
2919 						(1 << DMA_CUED_MULT1_OFF);
2920 			qpath = test_bit(PPC440SPE_ZERO_Q, &sw_desc->flags) ?
2921 					DMA_CUED_XOR_HB :
2922 					DMA_CUED_XOR_BASE |
2923 						(1 << DMA_CUED_MULT1_OFF);
2924 
2925 			/* Setup destination(s) in RXOR slot(s) */
2926 			iter = ppc440spe_get_group_entry(sw_desc, index++);
2927 			ppc440spe_desc_set_dest_addr(iter, chan,
2928 						paddr ? ppath : qpath,
2929 						paddr ? paddr : qaddr, 0);
2930 			if (!addr) {
2931 				/* two destinations */
2932 				iter = ppc440spe_get_group_entry(sw_desc,
2933 								 index++);
2934 				ppc440spe_desc_set_dest_addr(iter, chan,
2935 						qpath, qaddr, 0);
2936 			}
2937 
2938 			if (test_bit(PPC440SPE_DESC_WXOR, &sw_desc->flags)) {
2939 				/* Setup destination(s) in remaining WXOR
2940 				 * slots
2941 				 */
2942 				iter = ppc440spe_get_group_entry(sw_desc,
2943 								 index);
2944 				if (addr) {
2945 					/* one destination */
2946 					list_for_each_entry_from(iter,
2947 					    &sw_desc->group_list,
2948 					    chain_node)
2949 						ppc440spe_desc_set_dest_addr(
2950 							iter, chan,
2951 							DMA_CUED_XOR_BASE,
2952 							addr, 0);
2953 
2954 				} else {
2955 					/* two destinations */
2956 					list_for_each_entry_from(iter,
2957 					    &sw_desc->group_list,
2958 					    chain_node) {
2959 						ppc440spe_desc_set_dest_addr(
2960 							iter, chan,
2961 							DMA_CUED_XOR_BASE,
2962 							paddr, 0);
2963 						ppc440spe_desc_set_dest_addr(
2964 							iter, chan,
2965 							DMA_CUED_XOR_BASE,
2966 							qaddr, 1);
2967 					}
2968 				}
2969 			}
2970 
2971 		}
2972 		break;
2973 
2974 	case PPC440SPE_XOR_ID:
2975 		/* DMA2 descriptors have only 1 destination, so there are
2976 		 * two chains - one for each dest.
2977 		 * If we want to include destination into calculations,
2978 		 * then make dest addresses cued with mult=1 (XOR).
2979 		 */
2980 		ppath = test_bit(PPC440SPE_ZERO_P, &sw_desc->flags) ?
2981 				DMA_CUED_XOR_HB :
2982 				DMA_CUED_XOR_BASE |
2983 					(1 << DMA_CUED_MULT1_OFF);
2984 
2985 		qpath = test_bit(PPC440SPE_ZERO_Q, &sw_desc->flags) ?
2986 				DMA_CUED_XOR_HB :
2987 				DMA_CUED_XOR_BASE |
2988 					(1 << DMA_CUED_MULT1_OFF);
2989 
2990 		iter = ppc440spe_get_group_entry(sw_desc, 0);
2991 		for (i = 0; i < sw_desc->descs_per_op; i++) {
2992 			ppc440spe_desc_set_dest_addr(iter, chan,
2993 				paddr ? ppath : qpath,
2994 				paddr ? paddr : qaddr, 0);
2995 			iter = list_entry(iter->chain_node.next,
2996 					  struct ppc440spe_adma_desc_slot,
2997 					  chain_node);
2998 		}
2999 
3000 		if (!addr) {
3001 			/* Two destinations; setup Q here */
3002 			iter = ppc440spe_get_group_entry(sw_desc,
3003 				sw_desc->descs_per_op);
3004 			for (i = 0; i < sw_desc->descs_per_op; i++) {
3005 				ppc440spe_desc_set_dest_addr(iter,
3006 					chan, qpath, qaddr, 0);
3007 				iter = list_entry(iter->chain_node.next,
3008 						struct ppc440spe_adma_desc_slot,
3009 						chain_node);
3010 			}
3011 		}
3012 
3013 		break;
3014 	}
3015 }
3016 
3017 /**
3018  * ppc440spe_adma_pq_zero_sum_set_dest - set destination address into descriptor
3019  * for the PQ_ZERO_SUM operation
3020  */
3021 static void ppc440spe_adma_pqzero_sum_set_dest(
3022 		struct ppc440spe_adma_desc_slot *sw_desc,
3023 		dma_addr_t paddr, dma_addr_t qaddr)
3024 {
3025 	struct ppc440spe_adma_desc_slot *iter, *end;
3026 	struct ppc440spe_adma_chan *chan;
3027 	dma_addr_t addr = 0;
3028 	int idx;
3029 
3030 	chan = to_ppc440spe_adma_chan(sw_desc->async_tx.chan);
3031 
3032 	/* walk through the WXOR source list and set P/Q-destinations
3033 	 * for each slot
3034 	 */
3035 	idx = (paddr && qaddr) ? 2 : 1;
3036 	/* set end */
3037 	list_for_each_entry_reverse(end, &sw_desc->group_list,
3038 				    chain_node) {
3039 		if (!(--idx))
3040 			break;
3041 	}
3042 	/* set start */
3043 	idx = (paddr && qaddr) ? 2 : 1;
3044 	iter = ppc440spe_get_group_entry(sw_desc, idx);
3045 
3046 	if (paddr && qaddr) {
3047 		/* two destinations */
3048 		list_for_each_entry_from(iter, &sw_desc->group_list,
3049 					 chain_node) {
3050 			if (unlikely(iter == end))
3051 				break;
3052 			ppc440spe_desc_set_dest_addr(iter, chan,
3053 						DMA_CUED_XOR_BASE, paddr, 0);
3054 			ppc440spe_desc_set_dest_addr(iter, chan,
3055 						DMA_CUED_XOR_BASE, qaddr, 1);
3056 		}
3057 	} else {
3058 		/* one destination */
3059 		addr = paddr ? paddr : qaddr;
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, addr, 0);
3066 		}
3067 	}
3068 
3069 	/*  The remaining descriptors are DATACHECK. These have no need in
3070 	 * destination. Actually, these destinations are used there
3071 	 * as sources for check operation. So, set addr as source.
3072 	 */
3073 	ppc440spe_desc_set_src_addr(end, chan, 0, 0, addr ? addr : paddr);
3074 
3075 	if (!addr) {
3076 		end = list_entry(end->chain_node.next,
3077 				 struct ppc440spe_adma_desc_slot, chain_node);
3078 		ppc440spe_desc_set_src_addr(end, chan, 0, 0, qaddr);
3079 	}
3080 }
3081 
3082 /**
3083  * ppc440spe_desc_set_xor_src_cnt - set source count into descriptor
3084  */
3085 static inline void ppc440spe_desc_set_xor_src_cnt(
3086 			struct ppc440spe_adma_desc_slot *desc,
3087 			int src_cnt)
3088 {
3089 	struct xor_cb *hw_desc = desc->hw_desc;
3090 
3091 	hw_desc->cbc &= ~XOR_CDCR_OAC_MSK;
3092 	hw_desc->cbc |= src_cnt;
3093 }
3094 
3095 /**
3096  * ppc440spe_adma_pq_set_src - set source address into descriptor
3097  */
3098 static void ppc440spe_adma_pq_set_src(struct ppc440spe_adma_desc_slot *sw_desc,
3099 		dma_addr_t addr, int index)
3100 {
3101 	struct ppc440spe_adma_chan *chan;
3102 	dma_addr_t haddr = 0;
3103 	struct ppc440spe_adma_desc_slot *iter = NULL;
3104 
3105 	chan = to_ppc440spe_adma_chan(sw_desc->async_tx.chan);
3106 
3107 	switch (chan->device->id) {
3108 	case PPC440SPE_DMA0_ID:
3109 	case PPC440SPE_DMA1_ID:
3110 		/* DMA0,1 may do: WXOR, RXOR, RXOR+WXORs chain
3111 		 */
3112 		if (test_bit(PPC440SPE_DESC_RXOR, &sw_desc->flags)) {
3113 			/* RXOR-only or RXOR/WXOR operation */
3114 			int iskip = test_bit(PPC440SPE_DESC_RXOR12,
3115 				&sw_desc->flags) ?  2 : 3;
3116 
3117 			if (index == 0) {
3118 				/* 1st slot (RXOR) */
3119 				/* setup sources region (R1-2-3, R1-2-4,
3120 				 * or R1-2-5)
3121 				 */
3122 				if (test_bit(PPC440SPE_DESC_RXOR12,
3123 						&sw_desc->flags))
3124 					haddr = DMA_RXOR12 <<
3125 						DMA_CUED_REGION_OFF;
3126 				else if (test_bit(PPC440SPE_DESC_RXOR123,
3127 				    &sw_desc->flags))
3128 					haddr = DMA_RXOR123 <<
3129 						DMA_CUED_REGION_OFF;
3130 				else if (test_bit(PPC440SPE_DESC_RXOR124,
3131 				    &sw_desc->flags))
3132 					haddr = DMA_RXOR124 <<
3133 						DMA_CUED_REGION_OFF;
3134 				else if (test_bit(PPC440SPE_DESC_RXOR125,
3135 				    &sw_desc->flags))
3136 					haddr = DMA_RXOR125 <<
3137 						DMA_CUED_REGION_OFF;
3138 				else
3139 					BUG();
3140 				haddr |= DMA_CUED_XOR_BASE;
3141 				iter = ppc440spe_get_group_entry(sw_desc, 0);
3142 			} else if (index < iskip) {
3143 				/* 1st slot (RXOR)
3144 				 * shall actually set source address only once
3145 				 * instead of first <iskip>
3146 				 */
3147 				iter = NULL;
3148 			} else {
3149 				/* 2nd/3d and next slots (WXOR);
3150 				 * skip first slot with RXOR
3151 				 */
3152 				haddr = DMA_CUED_XOR_HB;
3153 				iter = ppc440spe_get_group_entry(sw_desc,
3154 				    index - iskip + sw_desc->dst_cnt);
3155 			}
3156 		} else {
3157 			int znum = 0;
3158 
3159 			/* WXOR-only operation; skip first slots with
3160 			 * zeroing destinations
3161 			 */
3162 			if (test_bit(PPC440SPE_ZERO_P, &sw_desc->flags))
3163 				znum++;
3164 			if (test_bit(PPC440SPE_ZERO_Q, &sw_desc->flags))
3165 				znum++;
3166 
3167 			haddr = DMA_CUED_XOR_HB;
3168 			iter = ppc440spe_get_group_entry(sw_desc,
3169 					index + znum);
3170 		}
3171 
3172 		if (likely(iter)) {
3173 			ppc440spe_desc_set_src_addr(iter, chan, 0, haddr, addr);
3174 
3175 			if (!index &&
3176 			    test_bit(PPC440SPE_DESC_RXOR, &sw_desc->flags) &&
3177 			    sw_desc->dst_cnt == 2) {
3178 				/* if we have two destinations for RXOR, then
3179 				 * setup source in the second descr too
3180 				 */
3181 				iter = ppc440spe_get_group_entry(sw_desc, 1);
3182 				ppc440spe_desc_set_src_addr(iter, chan, 0,
3183 					haddr, addr);
3184 			}
3185 		}
3186 		break;
3187 
3188 	case PPC440SPE_XOR_ID:
3189 		/* DMA2 may do Biskup */
3190 		iter = sw_desc->group_head;
3191 		if (iter->dst_cnt == 2) {
3192 			/* both P & Q calculations required; set P src here */
3193 			ppc440spe_adma_dma2rxor_set_src(iter, index, addr);
3194 
3195 			/* this is for Q */
3196 			iter = ppc440spe_get_group_entry(sw_desc,
3197 				sw_desc->descs_per_op);
3198 		}
3199 		ppc440spe_adma_dma2rxor_set_src(iter, index, addr);
3200 		break;
3201 	}
3202 }
3203 
3204 /**
3205  * ppc440spe_adma_memcpy_xor_set_src - set source address into descriptor
3206  */
3207 static void ppc440spe_adma_memcpy_xor_set_src(
3208 		struct ppc440spe_adma_desc_slot *sw_desc,
3209 		dma_addr_t addr, int index)
3210 {
3211 	struct ppc440spe_adma_chan *chan;
3212 
3213 	chan = to_ppc440spe_adma_chan(sw_desc->async_tx.chan);
3214 	sw_desc = sw_desc->group_head;
3215 
3216 	if (likely(sw_desc))
3217 		ppc440spe_desc_set_src_addr(sw_desc, chan, index, 0, addr);
3218 }
3219 
3220 /**
3221  * ppc440spe_adma_dma2rxor_inc_addr  -
3222  */
3223 static void ppc440spe_adma_dma2rxor_inc_addr(
3224 		struct ppc440spe_adma_desc_slot *desc,
3225 		struct ppc440spe_rxor *cursor, int index, int src_cnt)
3226 {
3227 	cursor->addr_count++;
3228 	if (index == src_cnt - 1) {
3229 		ppc440spe_desc_set_xor_src_cnt(desc, cursor->addr_count);
3230 	} else if (cursor->addr_count == XOR_MAX_OPS) {
3231 		ppc440spe_desc_set_xor_src_cnt(desc, cursor->addr_count);
3232 		cursor->addr_count = 0;
3233 		cursor->desc_count++;
3234 	}
3235 }
3236 
3237 /**
3238  * ppc440spe_adma_dma2rxor_prep_src - setup RXOR types in DMA2 CDB
3239  */
3240 static int ppc440spe_adma_dma2rxor_prep_src(
3241 		struct ppc440spe_adma_desc_slot *hdesc,
3242 		struct ppc440spe_rxor *cursor, int index,
3243 		int src_cnt, u32 addr)
3244 {
3245 	int rval = 0;
3246 	u32 sign;
3247 	struct ppc440spe_adma_desc_slot *desc = hdesc;
3248 	int i;
3249 
3250 	for (i = 0; i < cursor->desc_count; i++) {
3251 		desc = list_entry(hdesc->chain_node.next,
3252 				  struct ppc440spe_adma_desc_slot,
3253 				  chain_node);
3254 	}
3255 
3256 	switch (cursor->state) {
3257 	case 0:
3258 		if (addr == cursor->addrl + cursor->len) {
3259 			/* direct RXOR */
3260 			cursor->state = 1;
3261 			cursor->xor_count++;
3262 			if (index == src_cnt-1) {
3263 				ppc440spe_rxor_set_region(desc,
3264 					cursor->addr_count,
3265 					DMA_RXOR12 << DMA_CUED_REGION_OFF);
3266 				ppc440spe_adma_dma2rxor_inc_addr(
3267 					desc, cursor, index, src_cnt);
3268 			}
3269 		} else if (cursor->addrl == addr + cursor->len) {
3270 			/* reverse RXOR */
3271 			cursor->state = 1;
3272 			cursor->xor_count++;
3273 			set_bit(cursor->addr_count, &desc->reverse_flags[0]);
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 {
3282 			printk(KERN_ERR "Cannot build "
3283 				"DMA2 RXOR command block.\n");
3284 			BUG();
3285 		}
3286 		break;
3287 	case 1:
3288 		sign = test_bit(cursor->addr_count,
3289 				desc->reverse_flags)
3290 			? -1 : 1;
3291 		if (index == src_cnt-2 || (sign == -1
3292 			&& addr != cursor->addrl - 2*cursor->len)) {
3293 			cursor->state = 0;
3294 			cursor->xor_count = 1;
3295 			cursor->addrl = addr;
3296 			ppc440spe_rxor_set_region(desc,
3297 				cursor->addr_count,
3298 				DMA_RXOR12 << DMA_CUED_REGION_OFF);
3299 			ppc440spe_adma_dma2rxor_inc_addr(
3300 				desc, cursor, index, src_cnt);
3301 		} else if (addr == cursor->addrl + 2*sign*cursor->len) {
3302 			cursor->state = 2;
3303 			cursor->xor_count = 0;
3304 			ppc440spe_rxor_set_region(desc,
3305 				cursor->addr_count,
3306 				DMA_RXOR123 << DMA_CUED_REGION_OFF);
3307 			if (index == src_cnt-1) {
3308 				ppc440spe_adma_dma2rxor_inc_addr(
3309 					desc, cursor, index, src_cnt);
3310 			}
3311 		} else if (addr == cursor->addrl + 3*cursor->len) {
3312 			cursor->state = 2;
3313 			cursor->xor_count = 0;
3314 			ppc440spe_rxor_set_region(desc,
3315 				cursor->addr_count,
3316 				DMA_RXOR124 << DMA_CUED_REGION_OFF);
3317 			if (index == src_cnt-1) {
3318 				ppc440spe_adma_dma2rxor_inc_addr(
3319 					desc, cursor, index, src_cnt);
3320 			}
3321 		} else if (addr == cursor->addrl + 4*cursor->len) {
3322 			cursor->state = 2;
3323 			cursor->xor_count = 0;
3324 			ppc440spe_rxor_set_region(desc,
3325 				cursor->addr_count,
3326 				DMA_RXOR125 << DMA_CUED_REGION_OFF);
3327 			if (index == src_cnt-1) {
3328 				ppc440spe_adma_dma2rxor_inc_addr(
3329 					desc, cursor, index, src_cnt);
3330 			}
3331 		} else {
3332 			cursor->state = 0;
3333 			cursor->xor_count = 1;
3334 			cursor->addrl = addr;
3335 			ppc440spe_rxor_set_region(desc,
3336 				cursor->addr_count,
3337 				DMA_RXOR12 << DMA_CUED_REGION_OFF);
3338 			ppc440spe_adma_dma2rxor_inc_addr(
3339 				desc, cursor, index, src_cnt);
3340 		}
3341 		break;
3342 	case 2:
3343 		cursor->state = 0;
3344 		cursor->addrl = addr;
3345 		cursor->xor_count++;
3346 		if (index) {
3347 			ppc440spe_adma_dma2rxor_inc_addr(
3348 				desc, cursor, index, src_cnt);
3349 		}
3350 		break;
3351 	}
3352 
3353 	return rval;
3354 }
3355 
3356 /**
3357  * ppc440spe_adma_dma2rxor_set_src - set RXOR source address; it's assumed that
3358  *	ppc440spe_adma_dma2rxor_prep_src() has already done prior this call
3359  */
3360 static void ppc440spe_adma_dma2rxor_set_src(
3361 		struct ppc440spe_adma_desc_slot *desc,
3362 		int index, dma_addr_t addr)
3363 {
3364 	struct xor_cb *xcb = desc->hw_desc;
3365 	int k = 0, op = 0, lop = 0;
3366 
3367 	/* get the RXOR operand which corresponds to index addr */
3368 	while (op <= index) {
3369 		lop = op;
3370 		if (k == XOR_MAX_OPS) {
3371 			k = 0;
3372 			desc = list_entry(desc->chain_node.next,
3373 				struct ppc440spe_adma_desc_slot, chain_node);
3374 			xcb = desc->hw_desc;
3375 
3376 		}
3377 		if ((xcb->ops[k++].h & (DMA_RXOR12 << DMA_CUED_REGION_OFF)) ==
3378 		    (DMA_RXOR12 << DMA_CUED_REGION_OFF))
3379 			op += 2;
3380 		else
3381 			op += 3;
3382 	}
3383 
3384 	BUG_ON(k < 1);
3385 
3386 	if (test_bit(k-1, desc->reverse_flags)) {
3387 		/* reverse operand order; put last op in RXOR group */
3388 		if (index == op - 1)
3389 			ppc440spe_rxor_set_src(desc, k - 1, addr);
3390 	} else {
3391 		/* direct operand order; put first op in RXOR group */
3392 		if (index == lop)
3393 			ppc440spe_rxor_set_src(desc, k - 1, addr);
3394 	}
3395 }
3396 
3397 /**
3398  * ppc440spe_adma_dma2rxor_set_mult - set RXOR multipliers; it's assumed that
3399  *	ppc440spe_adma_dma2rxor_prep_src() has already done prior this call
3400  */
3401 static void ppc440spe_adma_dma2rxor_set_mult(
3402 		struct ppc440spe_adma_desc_slot *desc,
3403 		int index, u8 mult)
3404 {
3405 	struct xor_cb *xcb = desc->hw_desc;
3406 	int k = 0, op = 0, lop = 0;
3407 
3408 	/* get the RXOR operand which corresponds to index mult */
3409 	while (op <= index) {
3410 		lop = op;
3411 		if (k == XOR_MAX_OPS) {
3412 			k = 0;
3413 			desc = list_entry(desc->chain_node.next,
3414 					  struct ppc440spe_adma_desc_slot,
3415 					  chain_node);
3416 			xcb = desc->hw_desc;
3417 
3418 		}
3419 		if ((xcb->ops[k++].h & (DMA_RXOR12 << DMA_CUED_REGION_OFF)) ==
3420 		    (DMA_RXOR12 << DMA_CUED_REGION_OFF))
3421 			op += 2;
3422 		else
3423 			op += 3;
3424 	}
3425 
3426 	BUG_ON(k < 1);
3427 	if (test_bit(k-1, desc->reverse_flags)) {
3428 		/* reverse order */
3429 		ppc440spe_rxor_set_mult(desc, k - 1, op - index - 1, mult);
3430 	} else {
3431 		/* direct order */
3432 		ppc440spe_rxor_set_mult(desc, k - 1, index - lop, mult);
3433 	}
3434 }
3435 
3436 /**
3437  * ppc440spe_init_rxor_cursor -
3438  */
3439 static void ppc440spe_init_rxor_cursor(struct ppc440spe_rxor *cursor)
3440 {
3441 	memset(cursor, 0, sizeof(struct ppc440spe_rxor));
3442 	cursor->state = 2;
3443 }
3444 
3445 /**
3446  * ppc440spe_adma_pq_set_src_mult - set multiplication coefficient into
3447  * descriptor for the PQXOR operation
3448  */
3449 static void ppc440spe_adma_pq_set_src_mult(
3450 		struct ppc440spe_adma_desc_slot *sw_desc,
3451 		unsigned char mult, int index, int dst_pos)
3452 {
3453 	struct ppc440spe_adma_chan *chan;
3454 	u32 mult_idx, mult_dst;
3455 	struct ppc440spe_adma_desc_slot *iter = NULL, *iter1 = NULL;
3456 
3457 	chan = to_ppc440spe_adma_chan(sw_desc->async_tx.chan);
3458 
3459 	switch (chan->device->id) {
3460 	case PPC440SPE_DMA0_ID:
3461 	case PPC440SPE_DMA1_ID:
3462 		if (test_bit(PPC440SPE_DESC_RXOR, &sw_desc->flags)) {
3463 			int region = test_bit(PPC440SPE_DESC_RXOR12,
3464 					&sw_desc->flags) ? 2 : 3;
3465 
3466 			if (index < region) {
3467 				/* RXOR multipliers */
3468 				iter = ppc440spe_get_group_entry(sw_desc,
3469 					sw_desc->dst_cnt - 1);
3470 				if (sw_desc->dst_cnt == 2)
3471 					iter1 = ppc440spe_get_group_entry(
3472 							sw_desc, 0);
3473 
3474 				mult_idx = DMA_CUED_MULT1_OFF + (index << 3);
3475 				mult_dst = DMA_CDB_SG_SRC;
3476 			} else {
3477 				/* WXOR multiplier */
3478 				iter = ppc440spe_get_group_entry(sw_desc,
3479 							index - region +
3480 							sw_desc->dst_cnt);
3481 				mult_idx = DMA_CUED_MULT1_OFF;
3482 				mult_dst = dst_pos ? DMA_CDB_SG_DST2 :
3483 						     DMA_CDB_SG_DST1;
3484 			}
3485 		} else {
3486 			int znum = 0;
3487 
3488 			/* WXOR-only;
3489 			 * skip first slots with destinations (if ZERO_DST has
3490 			 * place)
3491 			 */
3492 			if (test_bit(PPC440SPE_ZERO_P, &sw_desc->flags))
3493 				znum++;
3494 			if (test_bit(PPC440SPE_ZERO_Q, &sw_desc->flags))
3495 				znum++;
3496 
3497 			iter = ppc440spe_get_group_entry(sw_desc, index + znum);
3498 			mult_idx = DMA_CUED_MULT1_OFF;
3499 			mult_dst = dst_pos ? DMA_CDB_SG_DST2 : DMA_CDB_SG_DST1;
3500 		}
3501 
3502 		if (likely(iter)) {
3503 			ppc440spe_desc_set_src_mult(iter, chan,
3504 				mult_idx, mult_dst, mult);
3505 
3506 			if (unlikely(iter1)) {
3507 				/* if we have two destinations for RXOR, then
3508 				 * we've just set Q mult. Set-up P now.
3509 				 */
3510 				ppc440spe_desc_set_src_mult(iter1, chan,
3511 					mult_idx, mult_dst, 1);
3512 			}
3513 
3514 		}
3515 		break;
3516 
3517 	case PPC440SPE_XOR_ID:
3518 		iter = sw_desc->group_head;
3519 		if (sw_desc->dst_cnt == 2) {
3520 			/* both P & Q calculations required; set P mult here */
3521 			ppc440spe_adma_dma2rxor_set_mult(iter, index, 1);
3522 
3523 			/* and then set Q mult */
3524 			iter = ppc440spe_get_group_entry(sw_desc,
3525 			       sw_desc->descs_per_op);
3526 		}
3527 		ppc440spe_adma_dma2rxor_set_mult(iter, index, mult);
3528 		break;
3529 	}
3530 }
3531 
3532 /**
3533  * ppc440spe_adma_free_chan_resources - free the resources allocated
3534  */
3535 static void ppc440spe_adma_free_chan_resources(struct dma_chan *chan)
3536 {
3537 	struct ppc440spe_adma_chan *ppc440spe_chan;
3538 	struct ppc440spe_adma_desc_slot *iter, *_iter;
3539 	int in_use_descs = 0;
3540 
3541 	ppc440spe_chan = to_ppc440spe_adma_chan(chan);
3542 	ppc440spe_adma_slot_cleanup(ppc440spe_chan);
3543 
3544 	spin_lock_bh(&ppc440spe_chan->lock);
3545 	list_for_each_entry_safe(iter, _iter, &ppc440spe_chan->chain,
3546 					chain_node) {
3547 		in_use_descs++;
3548 		list_del(&iter->chain_node);
3549 	}
3550 	list_for_each_entry_safe_reverse(iter, _iter,
3551 			&ppc440spe_chan->all_slots, slot_node) {
3552 		list_del(&iter->slot_node);
3553 		kfree(iter);
3554 		ppc440spe_chan->slots_allocated--;
3555 	}
3556 	ppc440spe_chan->last_used = NULL;
3557 
3558 	dev_dbg(ppc440spe_chan->device->common.dev,
3559 		"ppc440spe adma%d %s slots_allocated %d\n",
3560 		ppc440spe_chan->device->id,
3561 		__func__, ppc440spe_chan->slots_allocated);
3562 	spin_unlock_bh(&ppc440spe_chan->lock);
3563 
3564 	/* one is ok since we left it on there on purpose */
3565 	if (in_use_descs > 1)
3566 		printk(KERN_ERR "SPE: Freeing %d in use descriptors!\n",
3567 			in_use_descs - 1);
3568 }
3569 
3570 /**
3571  * ppc440spe_adma_tx_status - poll the status of an ADMA transaction
3572  * @chan: ADMA channel handle
3573  * @cookie: ADMA transaction identifier
3574  * @txstate: a holder for the current state of the channel
3575  */
3576 static enum dma_status ppc440spe_adma_tx_status(struct dma_chan *chan,
3577 			dma_cookie_t cookie, struct dma_tx_state *txstate)
3578 {
3579 	struct ppc440spe_adma_chan *ppc440spe_chan;
3580 	enum dma_status ret;
3581 
3582 	ppc440spe_chan = to_ppc440spe_adma_chan(chan);
3583 	ret = dma_cookie_status(chan, cookie, txstate);
3584 	if (ret == DMA_COMPLETE)
3585 		return ret;
3586 
3587 	ppc440spe_adma_slot_cleanup(ppc440spe_chan);
3588 
3589 	return dma_cookie_status(chan, cookie, txstate);
3590 }
3591 
3592 /**
3593  * ppc440spe_adma_eot_handler - end of transfer interrupt handler
3594  */
3595 static irqreturn_t ppc440spe_adma_eot_handler(int irq, void *data)
3596 {
3597 	struct ppc440spe_adma_chan *chan = data;
3598 
3599 	dev_dbg(chan->device->common.dev,
3600 		"ppc440spe adma%d: %s\n", chan->device->id, __func__);
3601 
3602 	tasklet_schedule(&chan->irq_tasklet);
3603 	ppc440spe_adma_device_clear_eot_status(chan);
3604 
3605 	return IRQ_HANDLED;
3606 }
3607 
3608 /**
3609  * ppc440spe_adma_err_handler - DMA error interrupt handler;
3610  *	do the same things as a eot handler
3611  */
3612 static irqreturn_t ppc440spe_adma_err_handler(int irq, void *data)
3613 {
3614 	struct ppc440spe_adma_chan *chan = data;
3615 
3616 	dev_dbg(chan->device->common.dev,
3617 		"ppc440spe adma%d: %s\n", chan->device->id, __func__);
3618 
3619 	tasklet_schedule(&chan->irq_tasklet);
3620 	ppc440spe_adma_device_clear_eot_status(chan);
3621 
3622 	return IRQ_HANDLED;
3623 }
3624 
3625 /**
3626  * ppc440spe_test_callback - called when test operation has been done
3627  */
3628 static void ppc440spe_test_callback(void *unused)
3629 {
3630 	complete(&ppc440spe_r6_test_comp);
3631 }
3632 
3633 /**
3634  * ppc440spe_adma_issue_pending - flush all pending descriptors to h/w
3635  */
3636 static void ppc440spe_adma_issue_pending(struct dma_chan *chan)
3637 {
3638 	struct ppc440spe_adma_chan *ppc440spe_chan;
3639 
3640 	ppc440spe_chan = to_ppc440spe_adma_chan(chan);
3641 	dev_dbg(ppc440spe_chan->device->common.dev,
3642 		"ppc440spe adma%d: %s %d \n", ppc440spe_chan->device->id,
3643 		__func__, ppc440spe_chan->pending);
3644 
3645 	if (ppc440spe_chan->pending) {
3646 		ppc440spe_chan->pending = 0;
3647 		ppc440spe_chan_append(ppc440spe_chan);
3648 	}
3649 }
3650 
3651 /**
3652  * ppc440spe_chan_start_null_xor - initiate the first XOR operation (DMA engines
3653  *	use FIFOs (as opposite to chains used in XOR) so this is a XOR
3654  *	specific operation)
3655  */
3656 static void ppc440spe_chan_start_null_xor(struct ppc440spe_adma_chan *chan)
3657 {
3658 	struct ppc440spe_adma_desc_slot *sw_desc, *group_start;
3659 	dma_cookie_t cookie;
3660 	int slot_cnt, slots_per_op;
3661 
3662 	dev_dbg(chan->device->common.dev,
3663 		"ppc440spe adma%d: %s\n", chan->device->id, __func__);
3664 
3665 	spin_lock_bh(&chan->lock);
3666 	slot_cnt = ppc440spe_chan_xor_slot_count(0, 2, &slots_per_op);
3667 	sw_desc = ppc440spe_adma_alloc_slots(chan, slot_cnt, slots_per_op);
3668 	if (sw_desc) {
3669 		group_start = sw_desc->group_head;
3670 		list_splice_init(&sw_desc->group_list, &chan->chain);
3671 		async_tx_ack(&sw_desc->async_tx);
3672 		ppc440spe_desc_init_null_xor(group_start);
3673 
3674 		cookie = dma_cookie_assign(&sw_desc->async_tx);
3675 
3676 		/* initialize the completed cookie to be less than
3677 		 * the most recently used cookie
3678 		 */
3679 		chan->common.completed_cookie = cookie - 1;
3680 
3681 		/* channel should not be busy */
3682 		BUG_ON(ppc440spe_chan_is_busy(chan));
3683 
3684 		/* set the descriptor address */
3685 		ppc440spe_chan_set_first_xor_descriptor(chan, sw_desc);
3686 
3687 		/* run the descriptor */
3688 		ppc440spe_chan_run(chan);
3689 	} else
3690 		printk(KERN_ERR "ppc440spe adma%d"
3691 			" failed to allocate null descriptor\n",
3692 			chan->device->id);
3693 	spin_unlock_bh(&chan->lock);
3694 }
3695 
3696 /**
3697  * ppc440spe_test_raid6 - test are RAID-6 capabilities enabled successfully.
3698  *	For this we just perform one WXOR operation with the same source
3699  *	and destination addresses, the GF-multiplier is 1; so if RAID-6
3700  *	capabilities are enabled then we'll get src/dst filled with zero.
3701  */
3702 static int ppc440spe_test_raid6(struct ppc440spe_adma_chan *chan)
3703 {
3704 	struct ppc440spe_adma_desc_slot *sw_desc, *iter;
3705 	struct page *pg;
3706 	char *a;
3707 	dma_addr_t dma_addr, addrs[2];
3708 	unsigned long op = 0;
3709 	int rval = 0;
3710 
3711 	set_bit(PPC440SPE_DESC_WXOR, &op);
3712 
3713 	pg = alloc_page(GFP_KERNEL);
3714 	if (!pg)
3715 		return -ENOMEM;
3716 
3717 	spin_lock_bh(&chan->lock);
3718 	sw_desc = ppc440spe_adma_alloc_slots(chan, 1, 1);
3719 	if (sw_desc) {
3720 		/* 1 src, 1 dsr, int_ena, WXOR */
3721 		ppc440spe_desc_init_dma01pq(sw_desc, 1, 1, 1, op);
3722 		list_for_each_entry(iter, &sw_desc->group_list, chain_node) {
3723 			ppc440spe_desc_set_byte_count(iter, chan, PAGE_SIZE);
3724 			iter->unmap_len = PAGE_SIZE;
3725 		}
3726 	} else {
3727 		rval = -EFAULT;
3728 		spin_unlock_bh(&chan->lock);
3729 		goto exit;
3730 	}
3731 	spin_unlock_bh(&chan->lock);
3732 
3733 	/* Fill the test page with ones */
3734 	memset(page_address(pg), 0xFF, PAGE_SIZE);
3735 	dma_addr = dma_map_page(chan->device->dev, pg, 0,
3736 				PAGE_SIZE, DMA_BIDIRECTIONAL);
3737 
3738 	/* Setup addresses */
3739 	ppc440spe_adma_pq_set_src(sw_desc, dma_addr, 0);
3740 	ppc440spe_adma_pq_set_src_mult(sw_desc, 1, 0, 0);
3741 	addrs[0] = dma_addr;
3742 	addrs[1] = 0;
3743 	ppc440spe_adma_pq_set_dest(sw_desc, addrs, DMA_PREP_PQ_DISABLE_Q);
3744 
3745 	async_tx_ack(&sw_desc->async_tx);
3746 	sw_desc->async_tx.callback = ppc440spe_test_callback;
3747 	sw_desc->async_tx.callback_param = NULL;
3748 
3749 	init_completion(&ppc440spe_r6_test_comp);
3750 
3751 	ppc440spe_adma_tx_submit(&sw_desc->async_tx);
3752 	ppc440spe_adma_issue_pending(&chan->common);
3753 
3754 	wait_for_completion(&ppc440spe_r6_test_comp);
3755 
3756 	/* Now check if the test page is zeroed */
3757 	a = page_address(pg);
3758 	if ((*(u32 *)a) == 0 && memcmp(a, a+4, PAGE_SIZE-4) == 0) {
3759 		/* page is zero - RAID-6 enabled */
3760 		rval = 0;
3761 	} else {
3762 		/* RAID-6 was not enabled */
3763 		rval = -EINVAL;
3764 	}
3765 exit:
3766 	__free_page(pg);
3767 	return rval;
3768 }
3769 
3770 static void ppc440spe_adma_init_capabilities(struct ppc440spe_adma_device *adev)
3771 {
3772 	switch (adev->id) {
3773 	case PPC440SPE_DMA0_ID:
3774 	case PPC440SPE_DMA1_ID:
3775 		dma_cap_set(DMA_MEMCPY, adev->common.cap_mask);
3776 		dma_cap_set(DMA_INTERRUPT, adev->common.cap_mask);
3777 		dma_cap_set(DMA_PQ, adev->common.cap_mask);
3778 		dma_cap_set(DMA_PQ_VAL, adev->common.cap_mask);
3779 		dma_cap_set(DMA_XOR_VAL, adev->common.cap_mask);
3780 		break;
3781 	case PPC440SPE_XOR_ID:
3782 		dma_cap_set(DMA_XOR, adev->common.cap_mask);
3783 		dma_cap_set(DMA_PQ, adev->common.cap_mask);
3784 		dma_cap_set(DMA_INTERRUPT, adev->common.cap_mask);
3785 		adev->common.cap_mask = adev->common.cap_mask;
3786 		break;
3787 	}
3788 
3789 	/* Set base routines */
3790 	adev->common.device_alloc_chan_resources =
3791 				ppc440spe_adma_alloc_chan_resources;
3792 	adev->common.device_free_chan_resources =
3793 				ppc440spe_adma_free_chan_resources;
3794 	adev->common.device_tx_status = ppc440spe_adma_tx_status;
3795 	adev->common.device_issue_pending = ppc440spe_adma_issue_pending;
3796 
3797 	/* Set prep routines based on capability */
3798 	if (dma_has_cap(DMA_MEMCPY, adev->common.cap_mask)) {
3799 		adev->common.device_prep_dma_memcpy =
3800 			ppc440spe_adma_prep_dma_memcpy;
3801 	}
3802 	if (dma_has_cap(DMA_XOR, adev->common.cap_mask)) {
3803 		adev->common.max_xor = XOR_MAX_OPS;
3804 		adev->common.device_prep_dma_xor =
3805 			ppc440spe_adma_prep_dma_xor;
3806 	}
3807 	if (dma_has_cap(DMA_PQ, adev->common.cap_mask)) {
3808 		switch (adev->id) {
3809 		case PPC440SPE_DMA0_ID:
3810 			dma_set_maxpq(&adev->common,
3811 				DMA0_FIFO_SIZE / sizeof(struct dma_cdb), 0);
3812 			break;
3813 		case PPC440SPE_DMA1_ID:
3814 			dma_set_maxpq(&adev->common,
3815 				DMA1_FIFO_SIZE / sizeof(struct dma_cdb), 0);
3816 			break;
3817 		case PPC440SPE_XOR_ID:
3818 			adev->common.max_pq = XOR_MAX_OPS * 3;
3819 			break;
3820 		}
3821 		adev->common.device_prep_dma_pq =
3822 			ppc440spe_adma_prep_dma_pq;
3823 	}
3824 	if (dma_has_cap(DMA_PQ_VAL, adev->common.cap_mask)) {
3825 		switch (adev->id) {
3826 		case PPC440SPE_DMA0_ID:
3827 			adev->common.max_pq = DMA0_FIFO_SIZE /
3828 						sizeof(struct dma_cdb);
3829 			break;
3830 		case PPC440SPE_DMA1_ID:
3831 			adev->common.max_pq = DMA1_FIFO_SIZE /
3832 						sizeof(struct dma_cdb);
3833 			break;
3834 		}
3835 		adev->common.device_prep_dma_pq_val =
3836 			ppc440spe_adma_prep_dma_pqzero_sum;
3837 	}
3838 	if (dma_has_cap(DMA_XOR_VAL, adev->common.cap_mask)) {
3839 		switch (adev->id) {
3840 		case PPC440SPE_DMA0_ID:
3841 			adev->common.max_xor = DMA0_FIFO_SIZE /
3842 						sizeof(struct dma_cdb);
3843 			break;
3844 		case PPC440SPE_DMA1_ID:
3845 			adev->common.max_xor = DMA1_FIFO_SIZE /
3846 						sizeof(struct dma_cdb);
3847 			break;
3848 		}
3849 		adev->common.device_prep_dma_xor_val =
3850 			ppc440spe_adma_prep_dma_xor_zero_sum;
3851 	}
3852 	if (dma_has_cap(DMA_INTERRUPT, adev->common.cap_mask)) {
3853 		adev->common.device_prep_dma_interrupt =
3854 			ppc440spe_adma_prep_dma_interrupt;
3855 	}
3856 	pr_info("%s: AMCC(R) PPC440SP(E) ADMA Engine: "
3857 	  "( %s%s%s%s%s%s)\n",
3858 	  dev_name(adev->dev),
3859 	  dma_has_cap(DMA_PQ, adev->common.cap_mask) ? "pq " : "",
3860 	  dma_has_cap(DMA_PQ_VAL, adev->common.cap_mask) ? "pq_val " : "",
3861 	  dma_has_cap(DMA_XOR, adev->common.cap_mask) ? "xor " : "",
3862 	  dma_has_cap(DMA_XOR_VAL, adev->common.cap_mask) ? "xor_val " : "",
3863 	  dma_has_cap(DMA_MEMCPY, adev->common.cap_mask) ? "memcpy " : "",
3864 	  dma_has_cap(DMA_INTERRUPT, adev->common.cap_mask) ? "intr " : "");
3865 }
3866 
3867 static int ppc440spe_adma_setup_irqs(struct ppc440spe_adma_device *adev,
3868 				     struct ppc440spe_adma_chan *chan,
3869 				     int *initcode)
3870 {
3871 	struct platform_device *ofdev;
3872 	struct device_node *np;
3873 	int ret;
3874 
3875 	ofdev = container_of(adev->dev, struct platform_device, dev);
3876 	np = ofdev->dev.of_node;
3877 	if (adev->id != PPC440SPE_XOR_ID) {
3878 		adev->err_irq = irq_of_parse_and_map(np, 1);
3879 		if (!adev->err_irq) {
3880 			dev_warn(adev->dev, "no err irq resource?\n");
3881 			*initcode = PPC_ADMA_INIT_IRQ2;
3882 			adev->err_irq = -ENXIO;
3883 		} else
3884 			atomic_inc(&ppc440spe_adma_err_irq_ref);
3885 	} else {
3886 		adev->err_irq = -ENXIO;
3887 	}
3888 
3889 	adev->irq = irq_of_parse_and_map(np, 0);
3890 	if (!adev->irq) {
3891 		dev_err(adev->dev, "no irq resource\n");
3892 		*initcode = PPC_ADMA_INIT_IRQ1;
3893 		ret = -ENXIO;
3894 		goto err_irq_map;
3895 	}
3896 	dev_dbg(adev->dev, "irq %d, err irq %d\n",
3897 		adev->irq, adev->err_irq);
3898 
3899 	ret = request_irq(adev->irq, ppc440spe_adma_eot_handler,
3900 			  0, dev_driver_string(adev->dev), chan);
3901 	if (ret) {
3902 		dev_err(adev->dev, "can't request irq %d\n",
3903 			adev->irq);
3904 		*initcode = PPC_ADMA_INIT_IRQ1;
3905 		ret = -EIO;
3906 		goto err_req1;
3907 	}
3908 
3909 	/* only DMA engines have a separate error IRQ
3910 	 * so it's Ok if err_irq < 0 in XOR engine case.
3911 	 */
3912 	if (adev->err_irq > 0) {
3913 		/* both DMA engines share common error IRQ */
3914 		ret = request_irq(adev->err_irq,
3915 				  ppc440spe_adma_err_handler,
3916 				  IRQF_SHARED,
3917 				  dev_driver_string(adev->dev),
3918 				  chan);
3919 		if (ret) {
3920 			dev_err(adev->dev, "can't request irq %d\n",
3921 				adev->err_irq);
3922 			*initcode = PPC_ADMA_INIT_IRQ2;
3923 			ret = -EIO;
3924 			goto err_req2;
3925 		}
3926 	}
3927 
3928 	if (adev->id == PPC440SPE_XOR_ID) {
3929 		/* enable XOR engine interrupts */
3930 		iowrite32be(XOR_IE_CBCIE_BIT | XOR_IE_ICBIE_BIT |
3931 			    XOR_IE_ICIE_BIT | XOR_IE_RPTIE_BIT,
3932 			    &adev->xor_reg->ier);
3933 	} else {
3934 		u32 mask, enable;
3935 
3936 		np = of_find_compatible_node(NULL, NULL, "ibm,i2o-440spe");
3937 		if (!np) {
3938 			pr_err("%s: can't find I2O device tree node\n",
3939 				__func__);
3940 			ret = -ENODEV;
3941 			goto err_req2;
3942 		}
3943 		adev->i2o_reg = of_iomap(np, 0);
3944 		if (!adev->i2o_reg) {
3945 			pr_err("%s: failed to map I2O registers\n", __func__);
3946 			of_node_put(np);
3947 			ret = -EINVAL;
3948 			goto err_req2;
3949 		}
3950 		of_node_put(np);
3951 		/* Unmask 'CS FIFO Attention' interrupts and
3952 		 * enable generating interrupts on errors
3953 		 */
3954 		enable = (adev->id == PPC440SPE_DMA0_ID) ?
3955 			 ~(I2O_IOPIM_P0SNE | I2O_IOPIM_P0EM) :
3956 			 ~(I2O_IOPIM_P1SNE | I2O_IOPIM_P1EM);
3957 		mask = ioread32(&adev->i2o_reg->iopim) & enable;
3958 		iowrite32(mask, &adev->i2o_reg->iopim);
3959 	}
3960 	return 0;
3961 
3962 err_req2:
3963 	free_irq(adev->irq, chan);
3964 err_req1:
3965 	irq_dispose_mapping(adev->irq);
3966 err_irq_map:
3967 	if (adev->err_irq > 0) {
3968 		if (atomic_dec_and_test(&ppc440spe_adma_err_irq_ref))
3969 			irq_dispose_mapping(adev->err_irq);
3970 	}
3971 	return ret;
3972 }
3973 
3974 static void ppc440spe_adma_release_irqs(struct ppc440spe_adma_device *adev,
3975 					struct ppc440spe_adma_chan *chan)
3976 {
3977 	u32 mask, disable;
3978 
3979 	if (adev->id == PPC440SPE_XOR_ID) {
3980 		/* disable XOR engine interrupts */
3981 		mask = ioread32be(&adev->xor_reg->ier);
3982 		mask &= ~(XOR_IE_CBCIE_BIT | XOR_IE_ICBIE_BIT |
3983 			  XOR_IE_ICIE_BIT | XOR_IE_RPTIE_BIT);
3984 		iowrite32be(mask, &adev->xor_reg->ier);
3985 	} else {
3986 		/* disable DMAx engine interrupts */
3987 		disable = (adev->id == PPC440SPE_DMA0_ID) ?
3988 			  (I2O_IOPIM_P0SNE | I2O_IOPIM_P0EM) :
3989 			  (I2O_IOPIM_P1SNE | I2O_IOPIM_P1EM);
3990 		mask = ioread32(&adev->i2o_reg->iopim) | disable;
3991 		iowrite32(mask, &adev->i2o_reg->iopim);
3992 	}
3993 	free_irq(adev->irq, chan);
3994 	irq_dispose_mapping(adev->irq);
3995 	if (adev->err_irq > 0) {
3996 		free_irq(adev->err_irq, chan);
3997 		if (atomic_dec_and_test(&ppc440spe_adma_err_irq_ref)) {
3998 			irq_dispose_mapping(adev->err_irq);
3999 			iounmap(adev->i2o_reg);
4000 		}
4001 	}
4002 }
4003 
4004 /**
4005  * ppc440spe_adma_probe - probe the asynch device
4006  */
4007 static int ppc440spe_adma_probe(struct platform_device *ofdev)
4008 {
4009 	struct device_node *np = ofdev->dev.of_node;
4010 	struct resource res;
4011 	struct ppc440spe_adma_device *adev;
4012 	struct ppc440spe_adma_chan *chan;
4013 	struct ppc_dma_chan_ref *ref, *_ref;
4014 	int ret = 0, initcode = PPC_ADMA_INIT_OK;
4015 	const u32 *idx;
4016 	int len;
4017 	void *regs;
4018 	u32 id, pool_size;
4019 
4020 	if (of_device_is_compatible(np, "amcc,xor-accelerator")) {
4021 		id = PPC440SPE_XOR_ID;
4022 		/* As far as the XOR engine is concerned, it does not
4023 		 * use FIFOs but uses linked list. So there is no dependency
4024 		 * between pool size to allocate and the engine configuration.
4025 		 */
4026 		pool_size = PAGE_SIZE << 1;
4027 	} else {
4028 		/* it is DMA0 or DMA1 */
4029 		idx = of_get_property(np, "cell-index", &len);
4030 		if (!idx || (len != sizeof(u32))) {
4031 			dev_err(&ofdev->dev, "Device node %pOF has missing "
4032 				"or invalid cell-index property\n",
4033 				np);
4034 			return -EINVAL;
4035 		}
4036 		id = *idx;
4037 		/* DMA0,1 engines use FIFO to maintain CDBs, so we
4038 		 * should allocate the pool accordingly to size of this
4039 		 * FIFO. Thus, the pool size depends on the FIFO depth:
4040 		 * how much CDBs pointers the FIFO may contain then so
4041 		 * much CDBs we should provide in the pool.
4042 		 * That is
4043 		 *   CDB size = 32B;
4044 		 *   CDBs number = (DMA0_FIFO_SIZE >> 3);
4045 		 *   Pool size = CDBs number * CDB size =
4046 		 *      = (DMA0_FIFO_SIZE >> 3) << 5 = DMA0_FIFO_SIZE << 2.
4047 		 */
4048 		pool_size = (id == PPC440SPE_DMA0_ID) ?
4049 			    DMA0_FIFO_SIZE : DMA1_FIFO_SIZE;
4050 		pool_size <<= 2;
4051 	}
4052 
4053 	if (of_address_to_resource(np, 0, &res)) {
4054 		dev_err(&ofdev->dev, "failed to get memory resource\n");
4055 		initcode = PPC_ADMA_INIT_MEMRES;
4056 		ret = -ENODEV;
4057 		goto out;
4058 	}
4059 
4060 	if (!request_mem_region(res.start, resource_size(&res),
4061 				dev_driver_string(&ofdev->dev))) {
4062 		dev_err(&ofdev->dev, "failed to request memory region %pR\n",
4063 			&res);
4064 		initcode = PPC_ADMA_INIT_MEMREG;
4065 		ret = -EBUSY;
4066 		goto out;
4067 	}
4068 
4069 	/* create a device */
4070 	adev = kzalloc(sizeof(*adev), GFP_KERNEL);
4071 	if (!adev) {
4072 		initcode = PPC_ADMA_INIT_ALLOC;
4073 		ret = -ENOMEM;
4074 		goto err_adev_alloc;
4075 	}
4076 
4077 	adev->id = id;
4078 	adev->pool_size = pool_size;
4079 	/* allocate coherent memory for hardware descriptors */
4080 	adev->dma_desc_pool_virt = dma_alloc_coherent(&ofdev->dev,
4081 					adev->pool_size, &adev->dma_desc_pool,
4082 					GFP_KERNEL);
4083 	if (adev->dma_desc_pool_virt == NULL) {
4084 		dev_err(&ofdev->dev, "failed to allocate %d bytes of coherent "
4085 			"memory for hardware descriptors\n",
4086 			adev->pool_size);
4087 		initcode = PPC_ADMA_INIT_COHERENT;
4088 		ret = -ENOMEM;
4089 		goto err_dma_alloc;
4090 	}
4091 	dev_dbg(&ofdev->dev, "allocated descriptor pool virt 0x%p phys 0x%llx\n",
4092 		adev->dma_desc_pool_virt, (u64)adev->dma_desc_pool);
4093 
4094 	regs = ioremap(res.start, resource_size(&res));
4095 	if (!regs) {
4096 		dev_err(&ofdev->dev, "failed to ioremap regs!\n");
4097 		ret = -ENOMEM;
4098 		goto err_regs_alloc;
4099 	}
4100 
4101 	if (adev->id == PPC440SPE_XOR_ID) {
4102 		adev->xor_reg = regs;
4103 		/* Reset XOR */
4104 		iowrite32be(XOR_CRSR_XASR_BIT, &adev->xor_reg->crsr);
4105 		iowrite32be(XOR_CRSR_64BA_BIT, &adev->xor_reg->crrr);
4106 	} else {
4107 		size_t fifo_size = (adev->id == PPC440SPE_DMA0_ID) ?
4108 				   DMA0_FIFO_SIZE : DMA1_FIFO_SIZE;
4109 		adev->dma_reg = regs;
4110 		/* DMAx_FIFO_SIZE is defined in bytes,
4111 		 * <fsiz> - is defined in number of CDB pointers (8byte).
4112 		 * DMA FIFO Length = CSlength + CPlength, where
4113 		 * CSlength = CPlength = (fsiz + 1) * 8.
4114 		 */
4115 		iowrite32(DMA_FIFO_ENABLE | ((fifo_size >> 3) - 2),
4116 			  &adev->dma_reg->fsiz);
4117 		/* Configure DMA engine */
4118 		iowrite32(DMA_CFG_DXEPR_HP | DMA_CFG_DFMPP_HP | DMA_CFG_FALGN,
4119 			  &adev->dma_reg->cfg);
4120 		/* Clear Status */
4121 		iowrite32(~0, &adev->dma_reg->dsts);
4122 	}
4123 
4124 	adev->dev = &ofdev->dev;
4125 	adev->common.dev = &ofdev->dev;
4126 	INIT_LIST_HEAD(&adev->common.channels);
4127 	platform_set_drvdata(ofdev, adev);
4128 
4129 	/* create a channel */
4130 	chan = kzalloc(sizeof(*chan), GFP_KERNEL);
4131 	if (!chan) {
4132 		initcode = PPC_ADMA_INIT_CHANNEL;
4133 		ret = -ENOMEM;
4134 		goto err_chan_alloc;
4135 	}
4136 
4137 	spin_lock_init(&chan->lock);
4138 	INIT_LIST_HEAD(&chan->chain);
4139 	INIT_LIST_HEAD(&chan->all_slots);
4140 	chan->device = adev;
4141 	chan->common.device = &adev->common;
4142 	dma_cookie_init(&chan->common);
4143 	list_add_tail(&chan->common.device_node, &adev->common.channels);
4144 	tasklet_init(&chan->irq_tasklet, ppc440spe_adma_tasklet,
4145 		     (unsigned long)chan);
4146 
4147 	/* allocate and map helper pages for async validation or
4148 	 * async_mult/async_sum_product operations on DMA0/1.
4149 	 */
4150 	if (adev->id != PPC440SPE_XOR_ID) {
4151 		chan->pdest_page = alloc_page(GFP_KERNEL);
4152 		chan->qdest_page = alloc_page(GFP_KERNEL);
4153 		if (!chan->pdest_page ||
4154 		    !chan->qdest_page) {
4155 			if (chan->pdest_page)
4156 				__free_page(chan->pdest_page);
4157 			if (chan->qdest_page)
4158 				__free_page(chan->qdest_page);
4159 			ret = -ENOMEM;
4160 			goto err_page_alloc;
4161 		}
4162 		chan->pdest = dma_map_page(&ofdev->dev, chan->pdest_page, 0,
4163 					   PAGE_SIZE, DMA_BIDIRECTIONAL);
4164 		chan->qdest = dma_map_page(&ofdev->dev, chan->qdest_page, 0,
4165 					   PAGE_SIZE, DMA_BIDIRECTIONAL);
4166 	}
4167 
4168 	ref = kmalloc(sizeof(*ref), GFP_KERNEL);
4169 	if (ref) {
4170 		ref->chan = &chan->common;
4171 		INIT_LIST_HEAD(&ref->node);
4172 		list_add_tail(&ref->node, &ppc440spe_adma_chan_list);
4173 	} else {
4174 		dev_err(&ofdev->dev, "failed to allocate channel reference!\n");
4175 		ret = -ENOMEM;
4176 		goto err_ref_alloc;
4177 	}
4178 
4179 	ret = ppc440spe_adma_setup_irqs(adev, chan, &initcode);
4180 	if (ret)
4181 		goto err_irq;
4182 
4183 	ppc440spe_adma_init_capabilities(adev);
4184 
4185 	ret = dma_async_device_register(&adev->common);
4186 	if (ret) {
4187 		initcode = PPC_ADMA_INIT_REGISTER;
4188 		dev_err(&ofdev->dev, "failed to register dma device\n");
4189 		goto err_dev_reg;
4190 	}
4191 
4192 	goto out;
4193 
4194 err_dev_reg:
4195 	ppc440spe_adma_release_irqs(adev, chan);
4196 err_irq:
4197 	list_for_each_entry_safe(ref, _ref, &ppc440spe_adma_chan_list, node) {
4198 		if (chan == to_ppc440spe_adma_chan(ref->chan)) {
4199 			list_del(&ref->node);
4200 			kfree(ref);
4201 		}
4202 	}
4203 err_ref_alloc:
4204 	if (adev->id != PPC440SPE_XOR_ID) {
4205 		dma_unmap_page(&ofdev->dev, chan->pdest,
4206 			       PAGE_SIZE, DMA_BIDIRECTIONAL);
4207 		dma_unmap_page(&ofdev->dev, chan->qdest,
4208 			       PAGE_SIZE, DMA_BIDIRECTIONAL);
4209 		__free_page(chan->pdest_page);
4210 		__free_page(chan->qdest_page);
4211 	}
4212 err_page_alloc:
4213 	kfree(chan);
4214 err_chan_alloc:
4215 	if (adev->id == PPC440SPE_XOR_ID)
4216 		iounmap(adev->xor_reg);
4217 	else
4218 		iounmap(adev->dma_reg);
4219 err_regs_alloc:
4220 	dma_free_coherent(adev->dev, adev->pool_size,
4221 			  adev->dma_desc_pool_virt,
4222 			  adev->dma_desc_pool);
4223 err_dma_alloc:
4224 	kfree(adev);
4225 err_adev_alloc:
4226 	release_mem_region(res.start, resource_size(&res));
4227 out:
4228 	if (id < PPC440SPE_ADMA_ENGINES_NUM)
4229 		ppc440spe_adma_devices[id] = initcode;
4230 
4231 	return ret;
4232 }
4233 
4234 /**
4235  * ppc440spe_adma_remove - remove the asynch device
4236  */
4237 static int ppc440spe_adma_remove(struct platform_device *ofdev)
4238 {
4239 	struct ppc440spe_adma_device *adev = platform_get_drvdata(ofdev);
4240 	struct device_node *np = ofdev->dev.of_node;
4241 	struct resource res;
4242 	struct dma_chan *chan, *_chan;
4243 	struct ppc_dma_chan_ref *ref, *_ref;
4244 	struct ppc440spe_adma_chan *ppc440spe_chan;
4245 
4246 	if (adev->id < PPC440SPE_ADMA_ENGINES_NUM)
4247 		ppc440spe_adma_devices[adev->id] = -1;
4248 
4249 	dma_async_device_unregister(&adev->common);
4250 
4251 	list_for_each_entry_safe(chan, _chan, &adev->common.channels,
4252 				 device_node) {
4253 		ppc440spe_chan = to_ppc440spe_adma_chan(chan);
4254 		ppc440spe_adma_release_irqs(adev, ppc440spe_chan);
4255 		tasklet_kill(&ppc440spe_chan->irq_tasklet);
4256 		if (adev->id != PPC440SPE_XOR_ID) {
4257 			dma_unmap_page(&ofdev->dev, ppc440spe_chan->pdest,
4258 					PAGE_SIZE, DMA_BIDIRECTIONAL);
4259 			dma_unmap_page(&ofdev->dev, ppc440spe_chan->qdest,
4260 					PAGE_SIZE, DMA_BIDIRECTIONAL);
4261 			__free_page(ppc440spe_chan->pdest_page);
4262 			__free_page(ppc440spe_chan->qdest_page);
4263 		}
4264 		list_for_each_entry_safe(ref, _ref, &ppc440spe_adma_chan_list,
4265 					 node) {
4266 			if (ppc440spe_chan ==
4267 			    to_ppc440spe_adma_chan(ref->chan)) {
4268 				list_del(&ref->node);
4269 				kfree(ref);
4270 			}
4271 		}
4272 		list_del(&chan->device_node);
4273 		kfree(ppc440spe_chan);
4274 	}
4275 
4276 	dma_free_coherent(adev->dev, adev->pool_size,
4277 			  adev->dma_desc_pool_virt, adev->dma_desc_pool);
4278 	if (adev->id == PPC440SPE_XOR_ID)
4279 		iounmap(adev->xor_reg);
4280 	else
4281 		iounmap(adev->dma_reg);
4282 	of_address_to_resource(np, 0, &res);
4283 	release_mem_region(res.start, resource_size(&res));
4284 	kfree(adev);
4285 	return 0;
4286 }
4287 
4288 /*
4289  * /sys driver interface to enable h/w RAID-6 capabilities
4290  * Files created in e.g. /sys/devices/plb.0/400100100.dma0/driver/
4291  * directory are "devices", "enable" and "poly".
4292  * "devices" shows available engines.
4293  * "enable" is used to enable RAID-6 capabilities or to check
4294  * whether these has been activated.
4295  * "poly" allows setting/checking used polynomial (for PPC440SPe only).
4296  */
4297 
4298 static ssize_t devices_show(struct device_driver *dev, char *buf)
4299 {
4300 	ssize_t size = 0;
4301 	int i;
4302 
4303 	for (i = 0; i < PPC440SPE_ADMA_ENGINES_NUM; i++) {
4304 		if (ppc440spe_adma_devices[i] == -1)
4305 			continue;
4306 		size += scnprintf(buf + size, PAGE_SIZE - size,
4307 				 "PPC440SP(E)-ADMA.%d: %s\n", i,
4308 				 ppc_adma_errors[ppc440spe_adma_devices[i]]);
4309 	}
4310 	return size;
4311 }
4312 static DRIVER_ATTR_RO(devices);
4313 
4314 static ssize_t enable_show(struct device_driver *dev, char *buf)
4315 {
4316 	return snprintf(buf, PAGE_SIZE,
4317 			"PPC440SP(e) RAID-6 capabilities are %sABLED.\n",
4318 			ppc440spe_r6_enabled ? "EN" : "DIS");
4319 }
4320 
4321 static ssize_t enable_store(struct device_driver *dev, const char *buf,
4322 			    size_t count)
4323 {
4324 	unsigned long val;
4325 
4326 	if (!count || count > 11)
4327 		return -EINVAL;
4328 
4329 	if (!ppc440spe_r6_tchan)
4330 		return -EFAULT;
4331 
4332 	/* Write a key */
4333 	sscanf(buf, "%lx", &val);
4334 	dcr_write(ppc440spe_mq_dcr_host, DCRN_MQ0_XORBA, val);
4335 	isync();
4336 
4337 	/* Verify whether it really works now */
4338 	if (ppc440spe_test_raid6(ppc440spe_r6_tchan) == 0) {
4339 		pr_info("PPC440SP(e) RAID-6 has been activated "
4340 			"successfully\n");
4341 		ppc440spe_r6_enabled = 1;
4342 	} else {
4343 		pr_info("PPC440SP(e) RAID-6 hasn't been activated!"
4344 			" Error key ?\n");
4345 		ppc440spe_r6_enabled = 0;
4346 	}
4347 	return count;
4348 }
4349 static DRIVER_ATTR_RW(enable);
4350 
4351 static ssize_t poly_show(struct device_driver *dev, char *buf)
4352 {
4353 	ssize_t size = 0;
4354 	u32 reg;
4355 
4356 #ifdef CONFIG_440SP
4357 	/* 440SP has fixed polynomial */
4358 	reg = 0x4d;
4359 #else
4360 	reg = dcr_read(ppc440spe_mq_dcr_host, DCRN_MQ0_CFBHL);
4361 	reg >>= MQ0_CFBHL_POLY;
4362 	reg &= 0xFF;
4363 #endif
4364 
4365 	size = snprintf(buf, PAGE_SIZE, "PPC440SP(e) RAID-6 driver "
4366 			"uses 0x1%02x polynomial.\n", reg);
4367 	return size;
4368 }
4369 
4370 static ssize_t poly_store(struct device_driver *dev, const char *buf,
4371 			  size_t count)
4372 {
4373 	unsigned long reg, val;
4374 
4375 #ifdef CONFIG_440SP
4376 	/* 440SP uses default 0x14D polynomial only */
4377 	return -EINVAL;
4378 #endif
4379 
4380 	if (!count || count > 6)
4381 		return -EINVAL;
4382 
4383 	/* e.g., 0x14D or 0x11D */
4384 	sscanf(buf, "%lx", &val);
4385 
4386 	if (val & ~0x1FF)
4387 		return -EINVAL;
4388 
4389 	val &= 0xFF;
4390 	reg = dcr_read(ppc440spe_mq_dcr_host, DCRN_MQ0_CFBHL);
4391 	reg &= ~(0xFF << MQ0_CFBHL_POLY);
4392 	reg |= val << MQ0_CFBHL_POLY;
4393 	dcr_write(ppc440spe_mq_dcr_host, DCRN_MQ0_CFBHL, reg);
4394 
4395 	return count;
4396 }
4397 static DRIVER_ATTR_RW(poly);
4398 
4399 /*
4400  * Common initialisation for RAID engines; allocate memory for
4401  * DMAx FIFOs, perform configuration common for all DMA engines.
4402  * Further DMA engine specific configuration is done at probe time.
4403  */
4404 static int ppc440spe_configure_raid_devices(void)
4405 {
4406 	struct device_node *np;
4407 	struct resource i2o_res;
4408 	struct i2o_regs __iomem *i2o_reg;
4409 	dcr_host_t i2o_dcr_host;
4410 	unsigned int dcr_base, dcr_len;
4411 	int i, ret;
4412 
4413 	np = of_find_compatible_node(NULL, NULL, "ibm,i2o-440spe");
4414 	if (!np) {
4415 		pr_err("%s: can't find I2O device tree node\n",
4416 			__func__);
4417 		return -ENODEV;
4418 	}
4419 
4420 	if (of_address_to_resource(np, 0, &i2o_res)) {
4421 		of_node_put(np);
4422 		return -EINVAL;
4423 	}
4424 
4425 	i2o_reg = of_iomap(np, 0);
4426 	if (!i2o_reg) {
4427 		pr_err("%s: failed to map I2O registers\n", __func__);
4428 		of_node_put(np);
4429 		return -EINVAL;
4430 	}
4431 
4432 	/* Get I2O DCRs base */
4433 	dcr_base = dcr_resource_start(np, 0);
4434 	dcr_len = dcr_resource_len(np, 0);
4435 	if (!dcr_base && !dcr_len) {
4436 		pr_err("%pOF: can't get DCR registers base/len!\n", np);
4437 		of_node_put(np);
4438 		iounmap(i2o_reg);
4439 		return -ENODEV;
4440 	}
4441 
4442 	i2o_dcr_host = dcr_map(np, dcr_base, dcr_len);
4443 	if (!DCR_MAP_OK(i2o_dcr_host)) {
4444 		pr_err("%pOF: failed to map DCRs!\n", np);
4445 		of_node_put(np);
4446 		iounmap(i2o_reg);
4447 		return -ENODEV;
4448 	}
4449 	of_node_put(np);
4450 
4451 	/* Provide memory regions for DMA's FIFOs: I2O, DMA0 and DMA1 share
4452 	 * the base address of FIFO memory space.
4453 	 * Actually we need twice more physical memory than programmed in the
4454 	 * <fsiz> register (because there are two FIFOs for each DMA: CP and CS)
4455 	 */
4456 	ppc440spe_dma_fifo_buf = kmalloc((DMA0_FIFO_SIZE + DMA1_FIFO_SIZE) << 1,
4457 					 GFP_KERNEL);
4458 	if (!ppc440spe_dma_fifo_buf) {
4459 		pr_err("%s: DMA FIFO buffer allocation failed.\n", __func__);
4460 		iounmap(i2o_reg);
4461 		dcr_unmap(i2o_dcr_host, dcr_len);
4462 		return -ENOMEM;
4463 	}
4464 
4465 	/*
4466 	 * Configure h/w
4467 	 */
4468 	/* Reset I2O/DMA */
4469 	mtdcri(SDR0, DCRN_SDR0_SRST, DCRN_SDR0_SRST_I2ODMA);
4470 	mtdcri(SDR0, DCRN_SDR0_SRST, 0);
4471 
4472 	/* Setup the base address of mmaped registers */
4473 	dcr_write(i2o_dcr_host, DCRN_I2O0_IBAH, (u32)(i2o_res.start >> 32));
4474 	dcr_write(i2o_dcr_host, DCRN_I2O0_IBAL, (u32)(i2o_res.start) |
4475 						I2O_REG_ENABLE);
4476 	dcr_unmap(i2o_dcr_host, dcr_len);
4477 
4478 	/* Setup FIFO memory space base address */
4479 	iowrite32(0, &i2o_reg->ifbah);
4480 	iowrite32(((u32)__pa(ppc440spe_dma_fifo_buf)), &i2o_reg->ifbal);
4481 
4482 	/* set zero FIFO size for I2O, so the whole
4483 	 * ppc440spe_dma_fifo_buf is used by DMAs.
4484 	 * DMAx_FIFOs will be configured while probe.
4485 	 */
4486 	iowrite32(0, &i2o_reg->ifsiz);
4487 	iounmap(i2o_reg);
4488 
4489 	/* To prepare WXOR/RXOR functionality we need access to
4490 	 * Memory Queue Module DCRs (finally it will be enabled
4491 	 * via /sys interface of the ppc440spe ADMA driver).
4492 	 */
4493 	np = of_find_compatible_node(NULL, NULL, "ibm,mq-440spe");
4494 	if (!np) {
4495 		pr_err("%s: can't find MQ device tree node\n",
4496 			__func__);
4497 		ret = -ENODEV;
4498 		goto out_free;
4499 	}
4500 
4501 	/* Get MQ DCRs base */
4502 	dcr_base = dcr_resource_start(np, 0);
4503 	dcr_len = dcr_resource_len(np, 0);
4504 	if (!dcr_base && !dcr_len) {
4505 		pr_err("%pOF: can't get DCR registers base/len!\n", np);
4506 		ret = -ENODEV;
4507 		goto out_mq;
4508 	}
4509 
4510 	ppc440spe_mq_dcr_host = dcr_map(np, dcr_base, dcr_len);
4511 	if (!DCR_MAP_OK(ppc440spe_mq_dcr_host)) {
4512 		pr_err("%pOF: failed to map DCRs!\n", np);
4513 		ret = -ENODEV;
4514 		goto out_mq;
4515 	}
4516 	of_node_put(np);
4517 	ppc440spe_mq_dcr_len = dcr_len;
4518 
4519 	/* Set HB alias */
4520 	dcr_write(ppc440spe_mq_dcr_host, DCRN_MQ0_BAUH, DMA_CUED_XOR_HB);
4521 
4522 	/* Set:
4523 	 * - LL transaction passing limit to 1;
4524 	 * - Memory controller cycle limit to 1;
4525 	 * - Galois Polynomial to 0x14d (default)
4526 	 */
4527 	dcr_write(ppc440spe_mq_dcr_host, DCRN_MQ0_CFBHL,
4528 		  (1 << MQ0_CFBHL_TPLM) | (1 << MQ0_CFBHL_HBCL) |
4529 		  (PPC440SPE_DEFAULT_POLY << MQ0_CFBHL_POLY));
4530 
4531 	atomic_set(&ppc440spe_adma_err_irq_ref, 0);
4532 	for (i = 0; i < PPC440SPE_ADMA_ENGINES_NUM; i++)
4533 		ppc440spe_adma_devices[i] = -1;
4534 
4535 	return 0;
4536 
4537 out_mq:
4538 	of_node_put(np);
4539 out_free:
4540 	kfree(ppc440spe_dma_fifo_buf);
4541 	return ret;
4542 }
4543 
4544 static const struct of_device_id ppc440spe_adma_of_match[] = {
4545 	{ .compatible	= "ibm,dma-440spe", },
4546 	{ .compatible	= "amcc,xor-accelerator", },
4547 	{},
4548 };
4549 MODULE_DEVICE_TABLE(of, ppc440spe_adma_of_match);
4550 
4551 static struct platform_driver ppc440spe_adma_driver = {
4552 	.probe = ppc440spe_adma_probe,
4553 	.remove = ppc440spe_adma_remove,
4554 	.driver = {
4555 		.name = "PPC440SP(E)-ADMA",
4556 		.of_match_table = ppc440spe_adma_of_match,
4557 	},
4558 };
4559 
4560 static __init int ppc440spe_adma_init(void)
4561 {
4562 	int ret;
4563 
4564 	ret = ppc440spe_configure_raid_devices();
4565 	if (ret)
4566 		return ret;
4567 
4568 	ret = platform_driver_register(&ppc440spe_adma_driver);
4569 	if (ret) {
4570 		pr_err("%s: failed to register platform driver\n",
4571 			__func__);
4572 		goto out_reg;
4573 	}
4574 
4575 	/* Initialization status */
4576 	ret = driver_create_file(&ppc440spe_adma_driver.driver,
4577 				 &driver_attr_devices);
4578 	if (ret)
4579 		goto out_dev;
4580 
4581 	/* RAID-6 h/w enable entry */
4582 	ret = driver_create_file(&ppc440spe_adma_driver.driver,
4583 				 &driver_attr_enable);
4584 	if (ret)
4585 		goto out_en;
4586 
4587 	/* GF polynomial to use */
4588 	ret = driver_create_file(&ppc440spe_adma_driver.driver,
4589 				 &driver_attr_poly);
4590 	if (!ret)
4591 		return ret;
4592 
4593 	driver_remove_file(&ppc440spe_adma_driver.driver,
4594 			   &driver_attr_enable);
4595 out_en:
4596 	driver_remove_file(&ppc440spe_adma_driver.driver,
4597 			   &driver_attr_devices);
4598 out_dev:
4599 	/* User will not be able to enable h/w RAID-6 */
4600 	pr_err("%s: failed to create RAID-6 driver interface\n",
4601 		__func__);
4602 	platform_driver_unregister(&ppc440spe_adma_driver);
4603 out_reg:
4604 	dcr_unmap(ppc440spe_mq_dcr_host, ppc440spe_mq_dcr_len);
4605 	kfree(ppc440spe_dma_fifo_buf);
4606 	return ret;
4607 }
4608 
4609 static void __exit ppc440spe_adma_exit(void)
4610 {
4611 	driver_remove_file(&ppc440spe_adma_driver.driver,
4612 			   &driver_attr_poly);
4613 	driver_remove_file(&ppc440spe_adma_driver.driver,
4614 			   &driver_attr_enable);
4615 	driver_remove_file(&ppc440spe_adma_driver.driver,
4616 			   &driver_attr_devices);
4617 	platform_driver_unregister(&ppc440spe_adma_driver);
4618 	dcr_unmap(ppc440spe_mq_dcr_host, ppc440spe_mq_dcr_len);
4619 	kfree(ppc440spe_dma_fifo_buf);
4620 }
4621 
4622 arch_initcall(ppc440spe_adma_init);
4623 module_exit(ppc440spe_adma_exit);
4624 
4625 MODULE_AUTHOR("Yuri Tikhonov <yur@emcraft.com>");
4626 MODULE_DESCRIPTION("PPC440SPE ADMA Engine Driver");
4627 MODULE_LICENSE("GPL");
4628