1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * Intel I/OAT DMA Linux driver
4  * Copyright(c) 2004 - 2015 Intel Corporation.
5  */
6 #include <linux/module.h>
7 #include <linux/pci.h>
8 #include <linux/gfp.h>
9 #include <linux/dmaengine.h>
10 #include <linux/dma-mapping.h>
11 #include <linux/prefetch.h>
12 #include "../dmaengine.h"
13 #include "registers.h"
14 #include "hw.h"
15 #include "dma.h"
16 
17 #define MAX_SCF	256
18 
19 /* provide a lookup table for setting the source address in the base or
20  * extended descriptor of an xor or pq descriptor
21  */
22 static const u8 xor_idx_to_desc = 0xe0;
23 static const u8 xor_idx_to_field[] = { 1, 4, 5, 6, 7, 0, 1, 2 };
24 static const u8 pq_idx_to_desc = 0xf8;
25 static const u8 pq16_idx_to_desc[] = { 0, 0, 1, 1, 1, 1, 1, 1, 1,
26 				       2, 2, 2, 2, 2, 2, 2 };
27 static const u8 pq_idx_to_field[] = { 1, 4, 5, 0, 1, 2, 4, 5 };
28 static const u8 pq16_idx_to_field[] = { 1, 4, 1, 2, 3, 4, 5, 6, 7,
29 					0, 1, 2, 3, 4, 5, 6 };
30 
xor_set_src(struct ioat_raw_descriptor * descs[2],dma_addr_t addr,u32 offset,int idx)31 static void xor_set_src(struct ioat_raw_descriptor *descs[2],
32 			dma_addr_t addr, u32 offset, int idx)
33 {
34 	struct ioat_raw_descriptor *raw = descs[xor_idx_to_desc >> idx & 1];
35 
36 	raw->field[xor_idx_to_field[idx]] = addr + offset;
37 }
38 
pq_get_src(struct ioat_raw_descriptor * descs[2],int idx)39 static dma_addr_t pq_get_src(struct ioat_raw_descriptor *descs[2], int idx)
40 {
41 	struct ioat_raw_descriptor *raw = descs[pq_idx_to_desc >> idx & 1];
42 
43 	return raw->field[pq_idx_to_field[idx]];
44 }
45 
pq16_get_src(struct ioat_raw_descriptor * desc[3],int idx)46 static dma_addr_t pq16_get_src(struct ioat_raw_descriptor *desc[3], int idx)
47 {
48 	struct ioat_raw_descriptor *raw = desc[pq16_idx_to_desc[idx]];
49 
50 	return raw->field[pq16_idx_to_field[idx]];
51 }
52 
pq_set_src(struct ioat_raw_descriptor * descs[2],dma_addr_t addr,u32 offset,u8 coef,int idx)53 static void pq_set_src(struct ioat_raw_descriptor *descs[2],
54 		       dma_addr_t addr, u32 offset, u8 coef, int idx)
55 {
56 	struct ioat_pq_descriptor *pq = (struct ioat_pq_descriptor *) descs[0];
57 	struct ioat_raw_descriptor *raw = descs[pq_idx_to_desc >> idx & 1];
58 
59 	raw->field[pq_idx_to_field[idx]] = addr + offset;
60 	pq->coef[idx] = coef;
61 }
62 
pq16_set_src(struct ioat_raw_descriptor * desc[3],dma_addr_t addr,u32 offset,u8 coef,unsigned idx)63 static void pq16_set_src(struct ioat_raw_descriptor *desc[3],
64 			dma_addr_t addr, u32 offset, u8 coef, unsigned idx)
65 {
66 	struct ioat_pq_descriptor *pq = (struct ioat_pq_descriptor *)desc[0];
67 	struct ioat_pq16a_descriptor *pq16 =
68 		(struct ioat_pq16a_descriptor *)desc[1];
69 	struct ioat_raw_descriptor *raw = desc[pq16_idx_to_desc[idx]];
70 
71 	raw->field[pq16_idx_to_field[idx]] = addr + offset;
72 
73 	if (idx < 8)
74 		pq->coef[idx] = coef;
75 	else
76 		pq16->coef[idx - 8] = coef;
77 }
78 
79 static struct ioat_sed_ent *
ioat3_alloc_sed(struct ioatdma_device * ioat_dma,unsigned int hw_pool)80 ioat3_alloc_sed(struct ioatdma_device *ioat_dma, unsigned int hw_pool)
81 {
82 	struct ioat_sed_ent *sed;
83 	gfp_t flags = __GFP_ZERO | GFP_ATOMIC;
84 
85 	sed = kmem_cache_alloc(ioat_sed_cache, flags);
86 	if (!sed)
87 		return NULL;
88 
89 	sed->hw_pool = hw_pool;
90 	sed->hw = dma_pool_alloc(ioat_dma->sed_hw_pool[hw_pool],
91 				 flags, &sed->dma);
92 	if (!sed->hw) {
93 		kmem_cache_free(ioat_sed_cache, sed);
94 		return NULL;
95 	}
96 
97 	return sed;
98 }
99 
100 struct dma_async_tx_descriptor *
ioat_dma_prep_memcpy_lock(struct dma_chan * c,dma_addr_t dma_dest,dma_addr_t dma_src,size_t len,unsigned long flags)101 ioat_dma_prep_memcpy_lock(struct dma_chan *c, dma_addr_t dma_dest,
102 			   dma_addr_t dma_src, size_t len, unsigned long flags)
103 {
104 	struct ioatdma_chan *ioat_chan = to_ioat_chan(c);
105 	struct ioat_dma_descriptor *hw;
106 	struct ioat_ring_ent *desc;
107 	dma_addr_t dst = dma_dest;
108 	dma_addr_t src = dma_src;
109 	size_t total_len = len;
110 	int num_descs, idx, i;
111 
112 	if (test_bit(IOAT_CHAN_DOWN, &ioat_chan->state))
113 		return NULL;
114 
115 	num_descs = ioat_xferlen_to_descs(ioat_chan, len);
116 	if (likely(num_descs) &&
117 	    ioat_check_space_lock(ioat_chan, num_descs) == 0)
118 		idx = ioat_chan->head;
119 	else
120 		return NULL;
121 	i = 0;
122 	do {
123 		size_t copy = min_t(size_t, len, 1 << ioat_chan->xfercap_log);
124 
125 		desc = ioat_get_ring_ent(ioat_chan, idx + i);
126 		hw = desc->hw;
127 
128 		hw->size = copy;
129 		hw->ctl = 0;
130 		hw->src_addr = src;
131 		hw->dst_addr = dst;
132 
133 		len -= copy;
134 		dst += copy;
135 		src += copy;
136 		dump_desc_dbg(ioat_chan, desc);
137 	} while (++i < num_descs);
138 
139 	desc->txd.flags = flags;
140 	desc->len = total_len;
141 	hw->ctl_f.int_en = !!(flags & DMA_PREP_INTERRUPT);
142 	hw->ctl_f.fence = !!(flags & DMA_PREP_FENCE);
143 	hw->ctl_f.compl_write = 1;
144 	dump_desc_dbg(ioat_chan, desc);
145 	/* we leave the channel locked to ensure in order submission */
146 
147 	return &desc->txd;
148 }
149 
150 
151 static struct dma_async_tx_descriptor *
__ioat_prep_xor_lock(struct dma_chan * c,enum sum_check_flags * result,dma_addr_t dest,dma_addr_t * src,unsigned int src_cnt,size_t len,unsigned long flags)152 __ioat_prep_xor_lock(struct dma_chan *c, enum sum_check_flags *result,
153 		      dma_addr_t dest, dma_addr_t *src, unsigned int src_cnt,
154 		      size_t len, unsigned long flags)
155 {
156 	struct ioatdma_chan *ioat_chan = to_ioat_chan(c);
157 	struct ioat_ring_ent *compl_desc;
158 	struct ioat_ring_ent *desc;
159 	struct ioat_ring_ent *ext;
160 	size_t total_len = len;
161 	struct ioat_xor_descriptor *xor;
162 	struct ioat_xor_ext_descriptor *xor_ex = NULL;
163 	struct ioat_dma_descriptor *hw;
164 	int num_descs, with_ext, idx, i;
165 	u32 offset = 0;
166 	u8 op = result ? IOAT_OP_XOR_VAL : IOAT_OP_XOR;
167 
168 	BUG_ON(src_cnt < 2);
169 
170 	num_descs = ioat_xferlen_to_descs(ioat_chan, len);
171 	/* we need 2x the number of descriptors to cover greater than 5
172 	 * sources
173 	 */
174 	if (src_cnt > 5) {
175 		with_ext = 1;
176 		num_descs *= 2;
177 	} else
178 		with_ext = 0;
179 
180 	/* completion writes from the raid engine may pass completion
181 	 * writes from the legacy engine, so we need one extra null
182 	 * (legacy) descriptor to ensure all completion writes arrive in
183 	 * order.
184 	 */
185 	if (likely(num_descs) &&
186 	    ioat_check_space_lock(ioat_chan, num_descs+1) == 0)
187 		idx = ioat_chan->head;
188 	else
189 		return NULL;
190 	i = 0;
191 	do {
192 		struct ioat_raw_descriptor *descs[2];
193 		size_t xfer_size = min_t(size_t,
194 					 len, 1 << ioat_chan->xfercap_log);
195 		int s;
196 
197 		desc = ioat_get_ring_ent(ioat_chan, idx + i);
198 		xor = desc->xor;
199 
200 		/* save a branch by unconditionally retrieving the
201 		 * extended descriptor xor_set_src() knows to not write
202 		 * to it in the single descriptor case
203 		 */
204 		ext = ioat_get_ring_ent(ioat_chan, idx + i + 1);
205 		xor_ex = ext->xor_ex;
206 
207 		descs[0] = (struct ioat_raw_descriptor *) xor;
208 		descs[1] = (struct ioat_raw_descriptor *) xor_ex;
209 		for (s = 0; s < src_cnt; s++)
210 			xor_set_src(descs, src[s], offset, s);
211 		xor->size = xfer_size;
212 		xor->dst_addr = dest + offset;
213 		xor->ctl = 0;
214 		xor->ctl_f.op = op;
215 		xor->ctl_f.src_cnt = src_cnt_to_hw(src_cnt);
216 
217 		len -= xfer_size;
218 		offset += xfer_size;
219 		dump_desc_dbg(ioat_chan, desc);
220 	} while ((i += 1 + with_ext) < num_descs);
221 
222 	/* last xor descriptor carries the unmap parameters and fence bit */
223 	desc->txd.flags = flags;
224 	desc->len = total_len;
225 	if (result)
226 		desc->result = result;
227 	xor->ctl_f.fence = !!(flags & DMA_PREP_FENCE);
228 
229 	/* completion descriptor carries interrupt bit */
230 	compl_desc = ioat_get_ring_ent(ioat_chan, idx + i);
231 	compl_desc->txd.flags = flags & DMA_PREP_INTERRUPT;
232 	hw = compl_desc->hw;
233 	hw->ctl = 0;
234 	hw->ctl_f.null = 1;
235 	hw->ctl_f.int_en = !!(flags & DMA_PREP_INTERRUPT);
236 	hw->ctl_f.compl_write = 1;
237 	hw->size = NULL_DESC_BUFFER_SIZE;
238 	dump_desc_dbg(ioat_chan, compl_desc);
239 
240 	/* we leave the channel locked to ensure in order submission */
241 	return &compl_desc->txd;
242 }
243 
244 struct dma_async_tx_descriptor *
ioat_prep_xor(struct dma_chan * chan,dma_addr_t dest,dma_addr_t * src,unsigned int src_cnt,size_t len,unsigned long flags)245 ioat_prep_xor(struct dma_chan *chan, dma_addr_t dest, dma_addr_t *src,
246 	       unsigned int src_cnt, size_t len, unsigned long flags)
247 {
248 	struct ioatdma_chan *ioat_chan = to_ioat_chan(chan);
249 
250 	if (test_bit(IOAT_CHAN_DOWN, &ioat_chan->state))
251 		return NULL;
252 
253 	return __ioat_prep_xor_lock(chan, NULL, dest, src, src_cnt, len, flags);
254 }
255 
256 struct dma_async_tx_descriptor *
ioat_prep_xor_val(struct dma_chan * chan,dma_addr_t * src,unsigned int src_cnt,size_t len,enum sum_check_flags * result,unsigned long flags)257 ioat_prep_xor_val(struct dma_chan *chan, dma_addr_t *src,
258 		    unsigned int src_cnt, size_t len,
259 		    enum sum_check_flags *result, unsigned long flags)
260 {
261 	struct ioatdma_chan *ioat_chan = to_ioat_chan(chan);
262 
263 	if (test_bit(IOAT_CHAN_DOWN, &ioat_chan->state))
264 		return NULL;
265 
266 	/* the cleanup routine only sets bits on validate failure, it
267 	 * does not clear bits on validate success... so clear it here
268 	 */
269 	*result = 0;
270 
271 	return __ioat_prep_xor_lock(chan, result, src[0], &src[1],
272 				     src_cnt - 1, len, flags);
273 }
274 
275 static void
dump_pq_desc_dbg(struct ioatdma_chan * ioat_chan,struct ioat_ring_ent * desc,struct ioat_ring_ent * ext)276 dump_pq_desc_dbg(struct ioatdma_chan *ioat_chan, struct ioat_ring_ent *desc,
277 		 struct ioat_ring_ent *ext)
278 {
279 	struct device *dev = to_dev(ioat_chan);
280 	struct ioat_pq_descriptor *pq = desc->pq;
281 	struct ioat_pq_ext_descriptor *pq_ex = ext ? ext->pq_ex : NULL;
282 	struct ioat_raw_descriptor *descs[] = { (void *) pq, (void *) pq_ex };
283 	int src_cnt = src_cnt_to_sw(pq->ctl_f.src_cnt);
284 	int i;
285 
286 	dev_dbg(dev, "desc[%d]: (%#llx->%#llx) flags: %#x"
287 		" sz: %#10.8x ctl: %#x (op: %#x int: %d compl: %d pq: '%s%s'"
288 		" src_cnt: %d)\n",
289 		desc_id(desc), (unsigned long long) desc->txd.phys,
290 		(unsigned long long) (pq_ex ? pq_ex->next : pq->next),
291 		desc->txd.flags, pq->size, pq->ctl, pq->ctl_f.op,
292 		pq->ctl_f.int_en, pq->ctl_f.compl_write,
293 		pq->ctl_f.p_disable ? "" : "p", pq->ctl_f.q_disable ? "" : "q",
294 		pq->ctl_f.src_cnt);
295 	for (i = 0; i < src_cnt; i++)
296 		dev_dbg(dev, "\tsrc[%d]: %#llx coef: %#x\n", i,
297 			(unsigned long long) pq_get_src(descs, i), pq->coef[i]);
298 	dev_dbg(dev, "\tP: %#llx\n", pq->p_addr);
299 	dev_dbg(dev, "\tQ: %#llx\n", pq->q_addr);
300 	dev_dbg(dev, "\tNEXT: %#llx\n", pq->next);
301 }
302 
dump_pq16_desc_dbg(struct ioatdma_chan * ioat_chan,struct ioat_ring_ent * desc)303 static void dump_pq16_desc_dbg(struct ioatdma_chan *ioat_chan,
304 			       struct ioat_ring_ent *desc)
305 {
306 	struct device *dev = to_dev(ioat_chan);
307 	struct ioat_pq_descriptor *pq = desc->pq;
308 	struct ioat_raw_descriptor *descs[] = { (void *)pq,
309 						(void *)pq,
310 						(void *)pq };
311 	int src_cnt = src16_cnt_to_sw(pq->ctl_f.src_cnt);
312 	int i;
313 
314 	if (desc->sed) {
315 		descs[1] = (void *)desc->sed->hw;
316 		descs[2] = (void *)desc->sed->hw + 64;
317 	}
318 
319 	dev_dbg(dev, "desc[%d]: (%#llx->%#llx) flags: %#x"
320 		" sz: %#x ctl: %#x (op: %#x int: %d compl: %d pq: '%s%s'"
321 		" src_cnt: %d)\n",
322 		desc_id(desc), (unsigned long long) desc->txd.phys,
323 		(unsigned long long) pq->next,
324 		desc->txd.flags, pq->size, pq->ctl,
325 		pq->ctl_f.op, pq->ctl_f.int_en,
326 		pq->ctl_f.compl_write,
327 		pq->ctl_f.p_disable ? "" : "p", pq->ctl_f.q_disable ? "" : "q",
328 		pq->ctl_f.src_cnt);
329 	for (i = 0; i < src_cnt; i++) {
330 		dev_dbg(dev, "\tsrc[%d]: %#llx coef: %#x\n", i,
331 			(unsigned long long) pq16_get_src(descs, i),
332 			pq->coef[i]);
333 	}
334 	dev_dbg(dev, "\tP: %#llx\n", pq->p_addr);
335 	dev_dbg(dev, "\tQ: %#llx\n", pq->q_addr);
336 }
337 
338 static struct dma_async_tx_descriptor *
__ioat_prep_pq_lock(struct dma_chan * c,enum sum_check_flags * result,const dma_addr_t * dst,const dma_addr_t * src,unsigned int src_cnt,const unsigned char * scf,size_t len,unsigned long flags)339 __ioat_prep_pq_lock(struct dma_chan *c, enum sum_check_flags *result,
340 		     const dma_addr_t *dst, const dma_addr_t *src,
341 		     unsigned int src_cnt, const unsigned char *scf,
342 		     size_t len, unsigned long flags)
343 {
344 	struct ioatdma_chan *ioat_chan = to_ioat_chan(c);
345 	struct ioatdma_device *ioat_dma = ioat_chan->ioat_dma;
346 	struct ioat_ring_ent *compl_desc;
347 	struct ioat_ring_ent *desc;
348 	struct ioat_ring_ent *ext;
349 	size_t total_len = len;
350 	struct ioat_pq_descriptor *pq;
351 	struct ioat_pq_ext_descriptor *pq_ex = NULL;
352 	struct ioat_dma_descriptor *hw;
353 	u32 offset = 0;
354 	u8 op = result ? IOAT_OP_PQ_VAL : IOAT_OP_PQ;
355 	int i, s, idx, with_ext, num_descs;
356 	int cb32 = (ioat_dma->version < IOAT_VER_3_3) ? 1 : 0;
357 
358 	dev_dbg(to_dev(ioat_chan), "%s\n", __func__);
359 	/* the engine requires at least two sources (we provide
360 	 * at least 1 implied source in the DMA_PREP_CONTINUE case)
361 	 */
362 	BUG_ON(src_cnt + dmaf_continue(flags) < 2);
363 
364 	num_descs = ioat_xferlen_to_descs(ioat_chan, len);
365 	/* we need 2x the number of descriptors to cover greater than 3
366 	 * sources (we need 1 extra source in the q-only continuation
367 	 * case and 3 extra sources in the p+q continuation case.
368 	 */
369 	if (src_cnt + dmaf_p_disabled_continue(flags) > 3 ||
370 	    (dmaf_continue(flags) && !dmaf_p_disabled_continue(flags))) {
371 		with_ext = 1;
372 		num_descs *= 2;
373 	} else
374 		with_ext = 0;
375 
376 	/* completion writes from the raid engine may pass completion
377 	 * writes from the legacy engine, so we need one extra null
378 	 * (legacy) descriptor to ensure all completion writes arrive in
379 	 * order.
380 	 */
381 	if (likely(num_descs) &&
382 	    ioat_check_space_lock(ioat_chan, num_descs + cb32) == 0)
383 		idx = ioat_chan->head;
384 	else
385 		return NULL;
386 	i = 0;
387 	do {
388 		struct ioat_raw_descriptor *descs[2];
389 		size_t xfer_size = min_t(size_t, len,
390 					 1 << ioat_chan->xfercap_log);
391 
392 		desc = ioat_get_ring_ent(ioat_chan, idx + i);
393 		pq = desc->pq;
394 
395 		/* save a branch by unconditionally retrieving the
396 		 * extended descriptor pq_set_src() knows to not write
397 		 * to it in the single descriptor case
398 		 */
399 		ext = ioat_get_ring_ent(ioat_chan, idx + i + with_ext);
400 		pq_ex = ext->pq_ex;
401 
402 		descs[0] = (struct ioat_raw_descriptor *) pq;
403 		descs[1] = (struct ioat_raw_descriptor *) pq_ex;
404 
405 		for (s = 0; s < src_cnt; s++)
406 			pq_set_src(descs, src[s], offset, scf[s], s);
407 
408 		/* see the comment for dma_maxpq in include/linux/dmaengine.h */
409 		if (dmaf_p_disabled_continue(flags))
410 			pq_set_src(descs, dst[1], offset, 1, s++);
411 		else if (dmaf_continue(flags)) {
412 			pq_set_src(descs, dst[0], offset, 0, s++);
413 			pq_set_src(descs, dst[1], offset, 1, s++);
414 			pq_set_src(descs, dst[1], offset, 0, s++);
415 		}
416 		pq->size = xfer_size;
417 		pq->p_addr = dst[0] + offset;
418 		pq->q_addr = dst[1] + offset;
419 		pq->ctl = 0;
420 		pq->ctl_f.op = op;
421 		/* we turn on descriptor write back error status */
422 		if (ioat_dma->cap & IOAT_CAP_DWBES)
423 			pq->ctl_f.wb_en = result ? 1 : 0;
424 		pq->ctl_f.src_cnt = src_cnt_to_hw(s);
425 		pq->ctl_f.p_disable = !!(flags & DMA_PREP_PQ_DISABLE_P);
426 		pq->ctl_f.q_disable = !!(flags & DMA_PREP_PQ_DISABLE_Q);
427 
428 		len -= xfer_size;
429 		offset += xfer_size;
430 	} while ((i += 1 + with_ext) < num_descs);
431 
432 	/* last pq descriptor carries the unmap parameters and fence bit */
433 	desc->txd.flags = flags;
434 	desc->len = total_len;
435 	if (result)
436 		desc->result = result;
437 	pq->ctl_f.fence = !!(flags & DMA_PREP_FENCE);
438 	dump_pq_desc_dbg(ioat_chan, desc, ext);
439 
440 	if (!cb32) {
441 		pq->ctl_f.int_en = !!(flags & DMA_PREP_INTERRUPT);
442 		pq->ctl_f.compl_write = 1;
443 		compl_desc = desc;
444 	} else {
445 		/* completion descriptor carries interrupt bit */
446 		compl_desc = ioat_get_ring_ent(ioat_chan, idx + i);
447 		compl_desc->txd.flags = flags & DMA_PREP_INTERRUPT;
448 		hw = compl_desc->hw;
449 		hw->ctl = 0;
450 		hw->ctl_f.null = 1;
451 		hw->ctl_f.int_en = !!(flags & DMA_PREP_INTERRUPT);
452 		hw->ctl_f.compl_write = 1;
453 		hw->size = NULL_DESC_BUFFER_SIZE;
454 		dump_desc_dbg(ioat_chan, compl_desc);
455 	}
456 
457 
458 	/* we leave the channel locked to ensure in order submission */
459 	return &compl_desc->txd;
460 }
461 
462 static struct dma_async_tx_descriptor *
__ioat_prep_pq16_lock(struct dma_chan * c,enum sum_check_flags * result,const dma_addr_t * dst,const dma_addr_t * src,unsigned int src_cnt,const unsigned char * scf,size_t len,unsigned long flags)463 __ioat_prep_pq16_lock(struct dma_chan *c, enum sum_check_flags *result,
464 		       const dma_addr_t *dst, const dma_addr_t *src,
465 		       unsigned int src_cnt, const unsigned char *scf,
466 		       size_t len, unsigned long flags)
467 {
468 	struct ioatdma_chan *ioat_chan = to_ioat_chan(c);
469 	struct ioatdma_device *ioat_dma = ioat_chan->ioat_dma;
470 	struct ioat_ring_ent *desc;
471 	size_t total_len = len;
472 	struct ioat_pq_descriptor *pq;
473 	u32 offset = 0;
474 	u8 op;
475 	int i, s, idx, num_descs;
476 
477 	/* this function is only called with 9-16 sources */
478 	op = result ? IOAT_OP_PQ_VAL_16S : IOAT_OP_PQ_16S;
479 
480 	dev_dbg(to_dev(ioat_chan), "%s\n", __func__);
481 
482 	num_descs = ioat_xferlen_to_descs(ioat_chan, len);
483 
484 	/*
485 	 * 16 source pq is only available on cb3.3 and has no completion
486 	 * write hw bug.
487 	 */
488 	if (num_descs && ioat_check_space_lock(ioat_chan, num_descs) == 0)
489 		idx = ioat_chan->head;
490 	else
491 		return NULL;
492 
493 	i = 0;
494 
495 	do {
496 		struct ioat_raw_descriptor *descs[4];
497 		size_t xfer_size = min_t(size_t, len,
498 					 1 << ioat_chan->xfercap_log);
499 
500 		desc = ioat_get_ring_ent(ioat_chan, idx + i);
501 		pq = desc->pq;
502 
503 		descs[0] = (struct ioat_raw_descriptor *) pq;
504 
505 		desc->sed = ioat3_alloc_sed(ioat_dma, (src_cnt-2) >> 3);
506 		if (!desc->sed) {
507 			dev_err(to_dev(ioat_chan),
508 				"%s: no free sed entries\n", __func__);
509 			return NULL;
510 		}
511 
512 		pq->sed_addr = desc->sed->dma;
513 		desc->sed->parent = desc;
514 
515 		descs[1] = (struct ioat_raw_descriptor *)desc->sed->hw;
516 		descs[2] = (void *)descs[1] + 64;
517 
518 		for (s = 0; s < src_cnt; s++)
519 			pq16_set_src(descs, src[s], offset, scf[s], s);
520 
521 		/* see the comment for dma_maxpq in include/linux/dmaengine.h */
522 		if (dmaf_p_disabled_continue(flags))
523 			pq16_set_src(descs, dst[1], offset, 1, s++);
524 		else if (dmaf_continue(flags)) {
525 			pq16_set_src(descs, dst[0], offset, 0, s++);
526 			pq16_set_src(descs, dst[1], offset, 1, s++);
527 			pq16_set_src(descs, dst[1], offset, 0, s++);
528 		}
529 
530 		pq->size = xfer_size;
531 		pq->p_addr = dst[0] + offset;
532 		pq->q_addr = dst[1] + offset;
533 		pq->ctl = 0;
534 		pq->ctl_f.op = op;
535 		pq->ctl_f.src_cnt = src16_cnt_to_hw(s);
536 		/* we turn on descriptor write back error status */
537 		if (ioat_dma->cap & IOAT_CAP_DWBES)
538 			pq->ctl_f.wb_en = result ? 1 : 0;
539 		pq->ctl_f.p_disable = !!(flags & DMA_PREP_PQ_DISABLE_P);
540 		pq->ctl_f.q_disable = !!(flags & DMA_PREP_PQ_DISABLE_Q);
541 
542 		len -= xfer_size;
543 		offset += xfer_size;
544 	} while (++i < num_descs);
545 
546 	/* last pq descriptor carries the unmap parameters and fence bit */
547 	desc->txd.flags = flags;
548 	desc->len = total_len;
549 	if (result)
550 		desc->result = result;
551 	pq->ctl_f.fence = !!(flags & DMA_PREP_FENCE);
552 
553 	/* with cb3.3 we should be able to do completion w/o a null desc */
554 	pq->ctl_f.int_en = !!(flags & DMA_PREP_INTERRUPT);
555 	pq->ctl_f.compl_write = 1;
556 
557 	dump_pq16_desc_dbg(ioat_chan, desc);
558 
559 	/* we leave the channel locked to ensure in order submission */
560 	return &desc->txd;
561 }
562 
src_cnt_flags(unsigned int src_cnt,unsigned long flags)563 static int src_cnt_flags(unsigned int src_cnt, unsigned long flags)
564 {
565 	if (dmaf_p_disabled_continue(flags))
566 		return src_cnt + 1;
567 	else if (dmaf_continue(flags))
568 		return src_cnt + 3;
569 	else
570 		return src_cnt;
571 }
572 
573 struct dma_async_tx_descriptor *
ioat_prep_pq(struct dma_chan * chan,dma_addr_t * dst,dma_addr_t * src,unsigned int src_cnt,const unsigned char * scf,size_t len,unsigned long flags)574 ioat_prep_pq(struct dma_chan *chan, dma_addr_t *dst, dma_addr_t *src,
575 	      unsigned int src_cnt, const unsigned char *scf, size_t len,
576 	      unsigned long flags)
577 {
578 	struct ioatdma_chan *ioat_chan = to_ioat_chan(chan);
579 
580 	if (test_bit(IOAT_CHAN_DOWN, &ioat_chan->state))
581 		return NULL;
582 
583 	/* specify valid address for disabled result */
584 	if (flags & DMA_PREP_PQ_DISABLE_P)
585 		dst[0] = dst[1];
586 	if (flags & DMA_PREP_PQ_DISABLE_Q)
587 		dst[1] = dst[0];
588 
589 	/* handle the single source multiply case from the raid6
590 	 * recovery path
591 	 */
592 	if ((flags & DMA_PREP_PQ_DISABLE_P) && src_cnt == 1) {
593 		dma_addr_t single_source[2];
594 		unsigned char single_source_coef[2];
595 
596 		BUG_ON(flags & DMA_PREP_PQ_DISABLE_Q);
597 		single_source[0] = src[0];
598 		single_source[1] = src[0];
599 		single_source_coef[0] = scf[0];
600 		single_source_coef[1] = 0;
601 
602 		return src_cnt_flags(src_cnt, flags) > 8 ?
603 			__ioat_prep_pq16_lock(chan, NULL, dst, single_source,
604 					       2, single_source_coef, len,
605 					       flags) :
606 			__ioat_prep_pq_lock(chan, NULL, dst, single_source, 2,
607 					     single_source_coef, len, flags);
608 
609 	} else {
610 		return src_cnt_flags(src_cnt, flags) > 8 ?
611 			__ioat_prep_pq16_lock(chan, NULL, dst, src, src_cnt,
612 					       scf, len, flags) :
613 			__ioat_prep_pq_lock(chan, NULL, dst, src, src_cnt,
614 					     scf, len, flags);
615 	}
616 }
617 
618 struct dma_async_tx_descriptor *
ioat_prep_pq_val(struct dma_chan * chan,dma_addr_t * pq,dma_addr_t * src,unsigned int src_cnt,const unsigned char * scf,size_t len,enum sum_check_flags * pqres,unsigned long flags)619 ioat_prep_pq_val(struct dma_chan *chan, dma_addr_t *pq, dma_addr_t *src,
620 		  unsigned int src_cnt, const unsigned char *scf, size_t len,
621 		  enum sum_check_flags *pqres, unsigned long flags)
622 {
623 	struct ioatdma_chan *ioat_chan = to_ioat_chan(chan);
624 
625 	if (test_bit(IOAT_CHAN_DOWN, &ioat_chan->state))
626 		return NULL;
627 
628 	/* specify valid address for disabled result */
629 	if (flags & DMA_PREP_PQ_DISABLE_P)
630 		pq[0] = pq[1];
631 	if (flags & DMA_PREP_PQ_DISABLE_Q)
632 		pq[1] = pq[0];
633 
634 	/* the cleanup routine only sets bits on validate failure, it
635 	 * does not clear bits on validate success... so clear it here
636 	 */
637 	*pqres = 0;
638 
639 	return src_cnt_flags(src_cnt, flags) > 8 ?
640 		__ioat_prep_pq16_lock(chan, pqres, pq, src, src_cnt, scf, len,
641 				       flags) :
642 		__ioat_prep_pq_lock(chan, pqres, pq, src, src_cnt, scf, len,
643 				     flags);
644 }
645 
646 struct dma_async_tx_descriptor *
ioat_prep_pqxor(struct dma_chan * chan,dma_addr_t dst,dma_addr_t * src,unsigned int src_cnt,size_t len,unsigned long flags)647 ioat_prep_pqxor(struct dma_chan *chan, dma_addr_t dst, dma_addr_t *src,
648 		 unsigned int src_cnt, size_t len, unsigned long flags)
649 {
650 	unsigned char scf[MAX_SCF];
651 	dma_addr_t pq[2];
652 	struct ioatdma_chan *ioat_chan = to_ioat_chan(chan);
653 
654 	if (test_bit(IOAT_CHAN_DOWN, &ioat_chan->state))
655 		return NULL;
656 
657 	if (src_cnt > MAX_SCF)
658 		return NULL;
659 
660 	memset(scf, 0, src_cnt);
661 	pq[0] = dst;
662 	flags |= DMA_PREP_PQ_DISABLE_Q;
663 	pq[1] = dst; /* specify valid address for disabled result */
664 
665 	return src_cnt_flags(src_cnt, flags) > 8 ?
666 		__ioat_prep_pq16_lock(chan, NULL, pq, src, src_cnt, scf, len,
667 				       flags) :
668 		__ioat_prep_pq_lock(chan, NULL, pq, src, src_cnt, scf, len,
669 				     flags);
670 }
671 
672 struct dma_async_tx_descriptor *
ioat_prep_pqxor_val(struct dma_chan * chan,dma_addr_t * src,unsigned int src_cnt,size_t len,enum sum_check_flags * result,unsigned long flags)673 ioat_prep_pqxor_val(struct dma_chan *chan, dma_addr_t *src,
674 		     unsigned int src_cnt, size_t len,
675 		     enum sum_check_flags *result, unsigned long flags)
676 {
677 	unsigned char scf[MAX_SCF];
678 	dma_addr_t pq[2];
679 	struct ioatdma_chan *ioat_chan = to_ioat_chan(chan);
680 
681 	if (test_bit(IOAT_CHAN_DOWN, &ioat_chan->state))
682 		return NULL;
683 
684 	if (src_cnt > MAX_SCF)
685 		return NULL;
686 
687 	/* the cleanup routine only sets bits on validate failure, it
688 	 * does not clear bits on validate success... so clear it here
689 	 */
690 	*result = 0;
691 
692 	memset(scf, 0, src_cnt);
693 	pq[0] = src[0];
694 	flags |= DMA_PREP_PQ_DISABLE_Q;
695 	pq[1] = pq[0]; /* specify valid address for disabled result */
696 
697 	return src_cnt_flags(src_cnt, flags) > 8 ?
698 		__ioat_prep_pq16_lock(chan, result, pq, &src[1], src_cnt - 1,
699 				       scf, len, flags) :
700 		__ioat_prep_pq_lock(chan, result, pq, &src[1], src_cnt - 1,
701 				     scf, len, flags);
702 }
703 
704 struct dma_async_tx_descriptor *
ioat_prep_interrupt_lock(struct dma_chan * c,unsigned long flags)705 ioat_prep_interrupt_lock(struct dma_chan *c, unsigned long flags)
706 {
707 	struct ioatdma_chan *ioat_chan = to_ioat_chan(c);
708 	struct ioat_ring_ent *desc;
709 	struct ioat_dma_descriptor *hw;
710 
711 	if (test_bit(IOAT_CHAN_DOWN, &ioat_chan->state))
712 		return NULL;
713 
714 	if (ioat_check_space_lock(ioat_chan, 1) == 0)
715 		desc = ioat_get_ring_ent(ioat_chan, ioat_chan->head);
716 	else
717 		return NULL;
718 
719 	hw = desc->hw;
720 	hw->ctl = 0;
721 	hw->ctl_f.null = 1;
722 	hw->ctl_f.int_en = 1;
723 	hw->ctl_f.fence = !!(flags & DMA_PREP_FENCE);
724 	hw->ctl_f.compl_write = 1;
725 	hw->size = NULL_DESC_BUFFER_SIZE;
726 	hw->src_addr = 0;
727 	hw->dst_addr = 0;
728 
729 	desc->txd.flags = flags;
730 	desc->len = 1;
731 
732 	dump_desc_dbg(ioat_chan, desc);
733 
734 	/* we leave the channel locked to ensure in order submission */
735 	return &desc->txd;
736 }
737 
738