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 */
22static const u8 xor_idx_to_desc = 0xe0;
23static const u8 xor_idx_to_field[] = { 1, 4, 5, 6, 7, 0, 1, 2 };
24static const u8 pq_idx_to_desc = 0xf8;
25static const u8 pq16_idx_to_desc[] = { 0, 0, 1, 1, 1, 1, 1, 1, 1,
26 2, 2, 2, 2, 2, 2, 2 };
27static const u8 pq_idx_to_field[] = { 1, 4, 5, 0, 1, 2, 4, 5 };
28static const u8 pq16_idx_to_field[] = { 1, 4, 1, 2, 3, 4, 5, 6, 7,
29 0, 1, 2, 3, 4, 5, 6 };
30
31static 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
39static 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
46static 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
53static 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
63static 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
79static struct ioat_sed_ent *
80ioat3_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(cachep: ioat_sed_cache, flags);
86 if (!sed)
87 return NULL;
88
89 sed->hw_pool = hw_pool;
90 sed->hw = dma_pool_alloc(pool: ioat_dma->sed_hw_pool[hw_pool],
91 mem_flags: flags, handle: &sed->dma);
92 if (!sed->hw) {
93 kmem_cache_free(s: ioat_sed_cache, objp: sed);
94 return NULL;
95 }
96
97 return sed;
98}
99
100struct dma_async_tx_descriptor *
101ioat_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: 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
151static struct dma_async_tx_descriptor *
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: 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: 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: 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, addr: src[s], offset, idx: 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: 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
244struct dma_async_tx_descriptor *
245ioat_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(c: chan);
249
250 if (test_bit(IOAT_CHAN_DOWN, &ioat_chan->state))
251 return NULL;
252
253 return __ioat_prep_xor_lock(c: chan, NULL, dest, src, src_cnt, len, flags);
254}
255
256struct dma_async_tx_descriptor *
257ioat_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(c: 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(c: chan, result, dest: src[0], src: &src[1],
272 src_cnt: src_cnt - 1, len, flags);
273}
274
275static void
276dump_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
303static 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
338static struct dma_async_tx_descriptor *
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: 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: 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: 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, addr: src[s], offset, coef: scf[s], idx: 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, addr: dst[1], offset, coef: 1, idx: s++);
411 else if (dmaf_continue(flags)) {
412 pq_set_src(descs, addr: dst[0], offset, coef: 0, idx: s++);
413 pq_set_src(descs, addr: dst[1], offset, coef: 1, idx: s++);
414 pq_set_src(descs, addr: dst[1], offset, coef: 0, idx: 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: 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
462static struct dma_async_tx_descriptor *
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: idx + i);
501 pq = desc->pq;
502
503 descs[0] = (struct ioat_raw_descriptor *) pq;
504
505 desc->sed = ioat3_alloc_sed(ioat_dma, hw_pool: (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(desc: descs, addr: src[s], offset, coef: scf[s], idx: 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(desc: descs, addr: dst[1], offset, coef: 1, idx: s++);
524 else if (dmaf_continue(flags)) {
525 pq16_set_src(desc: descs, addr: dst[0], offset, coef: 0, idx: s++);
526 pq16_set_src(desc: descs, addr: dst[1], offset, coef: 1, idx: s++);
527 pq16_set_src(desc: descs, addr: dst[1], offset, coef: 0, idx: 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
563static 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
573struct dma_async_tx_descriptor *
574ioat_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(c: 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(c: chan, NULL, dst, src: single_source,
604 src_cnt: 2, scf: single_source_coef, len,
605 flags) :
606 __ioat_prep_pq_lock(c: chan, NULL, dst, src: single_source, src_cnt: 2,
607 scf: single_source_coef, len, flags);
608
609 } else {
610 return src_cnt_flags(src_cnt, flags) > 8 ?
611 __ioat_prep_pq16_lock(c: chan, NULL, dst, src, src_cnt,
612 scf, len, flags) :
613 __ioat_prep_pq_lock(c: chan, NULL, dst, src, src_cnt,
614 scf, len, flags);
615 }
616}
617
618struct dma_async_tx_descriptor *
619ioat_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(c: 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(c: chan, result: pqres, dst: pq, src, src_cnt, scf, len,
641 flags) :
642 __ioat_prep_pq_lock(c: chan, result: pqres, dst: pq, src, src_cnt, scf, len,
643 flags);
644}
645
646struct dma_async_tx_descriptor *
647ioat_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(c: 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(c: chan, NULL, dst: pq, src, src_cnt, scf, len,
667 flags) :
668 __ioat_prep_pq_lock(c: chan, NULL, dst: pq, src, src_cnt, scf, len,
669 flags);
670}
671
672struct dma_async_tx_descriptor *
673ioat_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(c: 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(c: chan, result, dst: pq, src: &src[1], src_cnt: src_cnt - 1,
699 scf, len, flags) :
700 __ioat_prep_pq_lock(c: chan, result, dst: pq, src: &src[1], src_cnt: src_cnt - 1,
701 scf, len, flags);
702}
703
704struct dma_async_tx_descriptor *
705ioat_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, num_descs: 1) == 0)
715 desc = ioat_get_ring_ent(ioat_chan, idx: 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

source code of linux/drivers/dma/ioat/prep.c