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
7/*
8 * This driver supports an Intel I/OAT DMA engine, which does asynchronous
9 * copy operations.
10 */
11
12#include <linux/init.h>
13#include <linux/module.h>
14#include <linux/slab.h>
15#include <linux/pci.h>
16#include <linux/interrupt.h>
17#include <linux/dmaengine.h>
18#include <linux/delay.h>
19#include <linux/dma-mapping.h>
20#include <linux/workqueue.h>
21#include <linux/prefetch.h>
22#include <linux/sizes.h>
23#include "dma.h"
24#include "registers.h"
25#include "hw.h"
26
27#include "../dmaengine.h"
28
29static int completion_timeout = 200;
30module_param(completion_timeout, int, 0644);
31MODULE_PARM_DESC(completion_timeout,
32 "set ioat completion timeout [msec] (default 200 [msec])");
33static int idle_timeout = 2000;
34module_param(idle_timeout, int, 0644);
35MODULE_PARM_DESC(idle_timeout,
36 "set ioat idle timeout [msec] (default 2000 [msec])");
37
38#define IDLE_TIMEOUT msecs_to_jiffies(idle_timeout)
39#define COMPLETION_TIMEOUT msecs_to_jiffies(completion_timeout)
40
41static char *chanerr_str[] = {
42 "DMA Transfer Source Address Error",
43 "DMA Transfer Destination Address Error",
44 "Next Descriptor Address Error",
45 "Descriptor Error",
46 "Chan Address Value Error",
47 "CHANCMD Error",
48 "Chipset Uncorrectable Data Integrity Error",
49 "DMA Uncorrectable Data Integrity Error",
50 "Read Data Error",
51 "Write Data Error",
52 "Descriptor Control Error",
53 "Descriptor Transfer Size Error",
54 "Completion Address Error",
55 "Interrupt Configuration Error",
56 "Super extended descriptor Address Error",
57 "Unaffiliated Error",
58 "CRC or XOR P Error",
59 "XOR Q Error",
60 "Descriptor Count Error",
61 "DIF All F detect Error",
62 "Guard Tag verification Error",
63 "Application Tag verification Error",
64 "Reference Tag verification Error",
65 "Bundle Bit Error",
66 "Result DIF All F detect Error",
67 "Result Guard Tag verification Error",
68 "Result Application Tag verification Error",
69 "Result Reference Tag verification Error",
70};
71
72static void ioat_eh(struct ioatdma_chan *ioat_chan);
73
74static void ioat_print_chanerrs(struct ioatdma_chan *ioat_chan, u32 chanerr)
75{
76 int i;
77
78 for (i = 0; i < ARRAY_SIZE(chanerr_str); i++) {
79 if ((chanerr >> i) & 1) {
80 dev_err(to_dev(ioat_chan), "Err(%d): %s\n",
81 i, chanerr_str[i]);
82 }
83 }
84}
85
86/**
87 * ioat_dma_do_interrupt - handler used for single vector interrupt mode
88 * @irq: interrupt id
89 * @data: interrupt data
90 */
91irqreturn_t ioat_dma_do_interrupt(int irq, void *data)
92{
93 struct ioatdma_device *instance = data;
94 struct ioatdma_chan *ioat_chan;
95 unsigned long attnstatus;
96 int bit;
97 u8 intrctrl;
98
99 intrctrl = readb(addr: instance->reg_base + IOAT_INTRCTRL_OFFSET);
100
101 if (!(intrctrl & IOAT_INTRCTRL_MASTER_INT_EN))
102 return IRQ_NONE;
103
104 if (!(intrctrl & IOAT_INTRCTRL_INT_STATUS)) {
105 writeb(val: intrctrl, addr: instance->reg_base + IOAT_INTRCTRL_OFFSET);
106 return IRQ_NONE;
107 }
108
109 attnstatus = readl(addr: instance->reg_base + IOAT_ATTNSTATUS_OFFSET);
110 for_each_set_bit(bit, &attnstatus, BITS_PER_LONG) {
111 ioat_chan = ioat_chan_by_index(ioat_dma: instance, index: bit);
112 if (test_bit(IOAT_RUN, &ioat_chan->state))
113 tasklet_schedule(t: &ioat_chan->cleanup_task);
114 }
115
116 writeb(val: intrctrl, addr: instance->reg_base + IOAT_INTRCTRL_OFFSET);
117 return IRQ_HANDLED;
118}
119
120/**
121 * ioat_dma_do_interrupt_msix - handler used for vector-per-channel interrupt mode
122 * @irq: interrupt id
123 * @data: interrupt data
124 */
125irqreturn_t ioat_dma_do_interrupt_msix(int irq, void *data)
126{
127 struct ioatdma_chan *ioat_chan = data;
128
129 if (test_bit(IOAT_RUN, &ioat_chan->state))
130 tasklet_schedule(t: &ioat_chan->cleanup_task);
131
132 return IRQ_HANDLED;
133}
134
135void ioat_stop(struct ioatdma_chan *ioat_chan)
136{
137 struct ioatdma_device *ioat_dma = ioat_chan->ioat_dma;
138 struct pci_dev *pdev = ioat_dma->pdev;
139 int chan_id = chan_num(ioat_chan);
140 struct msix_entry *msix;
141
142 /* 1/ stop irq from firing tasklets
143 * 2/ stop the tasklet from re-arming irqs
144 */
145 clear_bit(IOAT_RUN, addr: &ioat_chan->state);
146
147 /* flush inflight interrupts */
148 switch (ioat_dma->irq_mode) {
149 case IOAT_MSIX:
150 msix = &ioat_dma->msix_entries[chan_id];
151 synchronize_irq(irq: msix->vector);
152 break;
153 case IOAT_MSI:
154 case IOAT_INTX:
155 synchronize_irq(irq: pdev->irq);
156 break;
157 default:
158 break;
159 }
160
161 /* flush inflight timers */
162 del_timer_sync(timer: &ioat_chan->timer);
163
164 /* flush inflight tasklet runs */
165 tasklet_kill(t: &ioat_chan->cleanup_task);
166
167 /* final cleanup now that everything is quiesced and can't re-arm */
168 ioat_cleanup_event(t: &ioat_chan->cleanup_task);
169}
170
171static void __ioat_issue_pending(struct ioatdma_chan *ioat_chan)
172{
173 ioat_chan->dmacount += ioat_ring_pending(ioat_chan);
174 ioat_chan->issued = ioat_chan->head;
175 writew(val: ioat_chan->dmacount,
176 addr: ioat_chan->reg_base + IOAT_CHAN_DMACOUNT_OFFSET);
177 dev_dbg(to_dev(ioat_chan),
178 "%s: head: %#x tail: %#x issued: %#x count: %#x\n",
179 __func__, ioat_chan->head, ioat_chan->tail,
180 ioat_chan->issued, ioat_chan->dmacount);
181}
182
183void ioat_issue_pending(struct dma_chan *c)
184{
185 struct ioatdma_chan *ioat_chan = to_ioat_chan(c);
186
187 if (ioat_ring_pending(ioat_chan)) {
188 spin_lock_bh(lock: &ioat_chan->prep_lock);
189 __ioat_issue_pending(ioat_chan);
190 spin_unlock_bh(lock: &ioat_chan->prep_lock);
191 }
192}
193
194/**
195 * ioat_update_pending - log pending descriptors
196 * @ioat_chan: ioat+ channel
197 *
198 * Check if the number of unsubmitted descriptors has exceeded the
199 * watermark. Called with prep_lock held
200 */
201static void ioat_update_pending(struct ioatdma_chan *ioat_chan)
202{
203 if (ioat_ring_pending(ioat_chan) > ioat_pending_level)
204 __ioat_issue_pending(ioat_chan);
205}
206
207static void __ioat_start_null_desc(struct ioatdma_chan *ioat_chan)
208{
209 struct ioat_ring_ent *desc;
210 struct ioat_dma_descriptor *hw;
211
212 if (ioat_ring_space(ioat_chan) < 1) {
213 dev_err(to_dev(ioat_chan),
214 "Unable to start null desc - ring full\n");
215 return;
216 }
217
218 dev_dbg(to_dev(ioat_chan),
219 "%s: head: %#x tail: %#x issued: %#x\n",
220 __func__, ioat_chan->head, ioat_chan->tail, ioat_chan->issued);
221 desc = ioat_get_ring_ent(ioat_chan, idx: ioat_chan->head);
222
223 hw = desc->hw;
224 hw->ctl = 0;
225 hw->ctl_f.null = 1;
226 hw->ctl_f.int_en = 1;
227 hw->ctl_f.compl_write = 1;
228 /* set size to non-zero value (channel returns error when size is 0) */
229 hw->size = NULL_DESC_BUFFER_SIZE;
230 hw->src_addr = 0;
231 hw->dst_addr = 0;
232 async_tx_ack(tx: &desc->txd);
233 ioat_set_chainaddr(ioat_chan, addr: desc->txd.phys);
234 dump_desc_dbg(ioat_chan, desc);
235 /* make sure descriptors are written before we submit */
236 wmb();
237 ioat_chan->head += 1;
238 __ioat_issue_pending(ioat_chan);
239}
240
241void ioat_start_null_desc(struct ioatdma_chan *ioat_chan)
242{
243 spin_lock_bh(lock: &ioat_chan->prep_lock);
244 if (!test_bit(IOAT_CHAN_DOWN, &ioat_chan->state))
245 __ioat_start_null_desc(ioat_chan);
246 spin_unlock_bh(lock: &ioat_chan->prep_lock);
247}
248
249static void __ioat_restart_chan(struct ioatdma_chan *ioat_chan)
250{
251 /* set the tail to be re-issued */
252 ioat_chan->issued = ioat_chan->tail;
253 ioat_chan->dmacount = 0;
254 mod_timer(timer: &ioat_chan->timer, expires: jiffies + COMPLETION_TIMEOUT);
255
256 dev_dbg(to_dev(ioat_chan),
257 "%s: head: %#x tail: %#x issued: %#x count: %#x\n",
258 __func__, ioat_chan->head, ioat_chan->tail,
259 ioat_chan->issued, ioat_chan->dmacount);
260
261 if (ioat_ring_pending(ioat_chan)) {
262 struct ioat_ring_ent *desc;
263
264 desc = ioat_get_ring_ent(ioat_chan, idx: ioat_chan->tail);
265 ioat_set_chainaddr(ioat_chan, addr: desc->txd.phys);
266 __ioat_issue_pending(ioat_chan);
267 } else
268 __ioat_start_null_desc(ioat_chan);
269}
270
271static int ioat_quiesce(struct ioatdma_chan *ioat_chan, unsigned long tmo)
272{
273 unsigned long end = jiffies + tmo;
274 int err = 0;
275 u32 status;
276
277 status = ioat_chansts(ioat_chan);
278 if (is_ioat_active(status) || is_ioat_idle(status))
279 ioat_suspend(ioat_chan);
280 while (is_ioat_active(status) || is_ioat_idle(status)) {
281 if (tmo && time_after(jiffies, end)) {
282 err = -ETIMEDOUT;
283 break;
284 }
285 status = ioat_chansts(ioat_chan);
286 cpu_relax();
287 }
288
289 return err;
290}
291
292static int ioat_reset_sync(struct ioatdma_chan *ioat_chan, unsigned long tmo)
293{
294 unsigned long end = jiffies + tmo;
295 int err = 0;
296
297 ioat_reset(ioat_chan);
298 while (ioat_reset_pending(ioat_chan)) {
299 if (end && time_after(jiffies, end)) {
300 err = -ETIMEDOUT;
301 break;
302 }
303 cpu_relax();
304 }
305
306 return err;
307}
308
309static dma_cookie_t ioat_tx_submit_unlock(struct dma_async_tx_descriptor *tx)
310 __releases(&ioat_chan->prep_lock)
311{
312 struct dma_chan *c = tx->chan;
313 struct ioatdma_chan *ioat_chan = to_ioat_chan(c);
314 dma_cookie_t cookie;
315
316 cookie = dma_cookie_assign(tx);
317 dev_dbg(to_dev(ioat_chan), "%s: cookie: %d\n", __func__, cookie);
318
319 if (!test_and_set_bit(IOAT_CHAN_ACTIVE, addr: &ioat_chan->state))
320 mod_timer(timer: &ioat_chan->timer, expires: jiffies + COMPLETION_TIMEOUT);
321
322 /* make descriptor updates visible before advancing ioat->head,
323 * this is purposefully not smp_wmb() since we are also
324 * publishing the descriptor updates to a dma device
325 */
326 wmb();
327
328 ioat_chan->head += ioat_chan->produce;
329
330 ioat_update_pending(ioat_chan);
331 spin_unlock_bh(lock: &ioat_chan->prep_lock);
332
333 return cookie;
334}
335
336static struct ioat_ring_ent *
337ioat_alloc_ring_ent(struct dma_chan *chan, int idx, gfp_t flags)
338{
339 struct ioat_dma_descriptor *hw;
340 struct ioat_ring_ent *desc;
341 struct ioatdma_chan *ioat_chan = to_ioat_chan(c: chan);
342 int chunk;
343 dma_addr_t phys;
344 u8 *pos;
345 off_t offs;
346
347 chunk = idx / IOAT_DESCS_PER_CHUNK;
348 idx &= (IOAT_DESCS_PER_CHUNK - 1);
349 offs = idx * IOAT_DESC_SZ;
350 pos = (u8 *)ioat_chan->descs[chunk].virt + offs;
351 phys = ioat_chan->descs[chunk].hw + offs;
352 hw = (struct ioat_dma_descriptor *)pos;
353 memset(hw, 0, sizeof(*hw));
354
355 desc = kmem_cache_zalloc(k: ioat_cache, flags);
356 if (!desc)
357 return NULL;
358
359 dma_async_tx_descriptor_init(tx: &desc->txd, chan);
360 desc->txd.tx_submit = ioat_tx_submit_unlock;
361 desc->hw = hw;
362 desc->txd.phys = phys;
363 return desc;
364}
365
366void ioat_free_ring_ent(struct ioat_ring_ent *desc, struct dma_chan *chan)
367{
368 kmem_cache_free(s: ioat_cache, objp: desc);
369}
370
371struct ioat_ring_ent **
372ioat_alloc_ring(struct dma_chan *c, int order, gfp_t flags)
373{
374 struct ioatdma_chan *ioat_chan = to_ioat_chan(c);
375 struct ioatdma_device *ioat_dma = ioat_chan->ioat_dma;
376 struct ioat_ring_ent **ring;
377 int total_descs = 1 << order;
378 int i, chunks;
379
380 /* allocate the array to hold the software ring */
381 ring = kcalloc(n: total_descs, size: sizeof(*ring), flags);
382 if (!ring)
383 return NULL;
384
385 chunks = (total_descs * IOAT_DESC_SZ) / IOAT_CHUNK_SIZE;
386 ioat_chan->desc_chunks = chunks;
387
388 for (i = 0; i < chunks; i++) {
389 struct ioat_descs *descs = &ioat_chan->descs[i];
390
391 descs->virt = dma_alloc_coherent(to_dev(ioat_chan),
392 IOAT_CHUNK_SIZE, dma_handle: &descs->hw, gfp: flags);
393 if (!descs->virt) {
394 int idx;
395
396 for (idx = 0; idx < i; idx++) {
397 descs = &ioat_chan->descs[idx];
398 dma_free_coherent(to_dev(ioat_chan),
399 IOAT_CHUNK_SIZE,
400 cpu_addr: descs->virt, dma_handle: descs->hw);
401 descs->virt = NULL;
402 descs->hw = 0;
403 }
404
405 ioat_chan->desc_chunks = 0;
406 kfree(objp: ring);
407 return NULL;
408 }
409 }
410
411 for (i = 0; i < total_descs; i++) {
412 ring[i] = ioat_alloc_ring_ent(chan: c, idx: i, flags);
413 if (!ring[i]) {
414 int idx;
415
416 while (i--)
417 ioat_free_ring_ent(desc: ring[i], chan: c);
418
419 for (idx = 0; idx < ioat_chan->desc_chunks; idx++) {
420 dma_free_coherent(to_dev(ioat_chan),
421 IOAT_CHUNK_SIZE,
422 cpu_addr: ioat_chan->descs[idx].virt,
423 dma_handle: ioat_chan->descs[idx].hw);
424 ioat_chan->descs[idx].virt = NULL;
425 ioat_chan->descs[idx].hw = 0;
426 }
427
428 ioat_chan->desc_chunks = 0;
429 kfree(objp: ring);
430 return NULL;
431 }
432 set_desc_id(ring[i], i);
433 }
434
435 /* link descs */
436 for (i = 0; i < total_descs-1; i++) {
437 struct ioat_ring_ent *next = ring[i+1];
438 struct ioat_dma_descriptor *hw = ring[i]->hw;
439
440 hw->next = next->txd.phys;
441 }
442 ring[i]->hw->next = ring[0]->txd.phys;
443
444 /* setup descriptor pre-fetching for v3.4 */
445 if (ioat_dma->cap & IOAT_CAP_DPS) {
446 u16 drsctl = IOAT_CHAN_DRSZ_2MB | IOAT_CHAN_DRS_EN;
447
448 if (chunks == 1)
449 drsctl |= IOAT_CHAN_DRS_AUTOWRAP;
450
451 writew(val: drsctl, addr: ioat_chan->reg_base + IOAT_CHAN_DRSCTL_OFFSET);
452
453 }
454
455 return ring;
456}
457
458/**
459 * ioat_check_space_lock - verify space and grab ring producer lock
460 * @ioat_chan: ioat,3 channel (ring) to operate on
461 * @num_descs: allocation length
462 */
463int ioat_check_space_lock(struct ioatdma_chan *ioat_chan, int num_descs)
464 __acquires(&ioat_chan->prep_lock)
465{
466 spin_lock_bh(lock: &ioat_chan->prep_lock);
467 /* never allow the last descriptor to be consumed, we need at
468 * least one free at all times to allow for on-the-fly ring
469 * resizing.
470 */
471 if (likely(ioat_ring_space(ioat_chan) > num_descs)) {
472 dev_dbg(to_dev(ioat_chan), "%s: num_descs: %d (%x:%x:%x)\n",
473 __func__, num_descs, ioat_chan->head,
474 ioat_chan->tail, ioat_chan->issued);
475 ioat_chan->produce = num_descs;
476 return 0; /* with ioat->prep_lock held */
477 }
478 spin_unlock_bh(lock: &ioat_chan->prep_lock);
479
480 dev_dbg_ratelimited(to_dev(ioat_chan),
481 "%s: ring full! num_descs: %d (%x:%x:%x)\n",
482 __func__, num_descs, ioat_chan->head,
483 ioat_chan->tail, ioat_chan->issued);
484
485 /* progress reclaim in the allocation failure case we may be
486 * called under bh_disabled so we need to trigger the timer
487 * event directly
488 */
489 if (time_is_before_jiffies(ioat_chan->timer.expires)
490 && timer_pending(timer: &ioat_chan->timer)) {
491 mod_timer(timer: &ioat_chan->timer, expires: jiffies + COMPLETION_TIMEOUT);
492 ioat_timer_event(t: &ioat_chan->timer);
493 }
494
495 return -ENOMEM;
496}
497
498static bool desc_has_ext(struct ioat_ring_ent *desc)
499{
500 struct ioat_dma_descriptor *hw = desc->hw;
501
502 if (hw->ctl_f.op == IOAT_OP_XOR ||
503 hw->ctl_f.op == IOAT_OP_XOR_VAL) {
504 struct ioat_xor_descriptor *xor = desc->xor;
505
506 if (src_cnt_to_sw(xor->ctl_f.src_cnt) > 5)
507 return true;
508 } else if (hw->ctl_f.op == IOAT_OP_PQ ||
509 hw->ctl_f.op == IOAT_OP_PQ_VAL) {
510 struct ioat_pq_descriptor *pq = desc->pq;
511
512 if (src_cnt_to_sw(pq->ctl_f.src_cnt) > 3)
513 return true;
514 }
515
516 return false;
517}
518
519static void
520ioat_free_sed(struct ioatdma_device *ioat_dma, struct ioat_sed_ent *sed)
521{
522 if (!sed)
523 return;
524
525 dma_pool_free(pool: ioat_dma->sed_hw_pool[sed->hw_pool], vaddr: sed->hw, addr: sed->dma);
526 kmem_cache_free(s: ioat_sed_cache, objp: sed);
527}
528
529static u64 ioat_get_current_completion(struct ioatdma_chan *ioat_chan)
530{
531 u64 phys_complete;
532 u64 completion;
533
534 completion = *ioat_chan->completion;
535 phys_complete = ioat_chansts_to_addr(status: completion);
536
537 dev_dbg(to_dev(ioat_chan), "%s: phys_complete: %#llx\n", __func__,
538 (unsigned long long) phys_complete);
539
540 return phys_complete;
541}
542
543static bool ioat_cleanup_preamble(struct ioatdma_chan *ioat_chan,
544 u64 *phys_complete)
545{
546 *phys_complete = ioat_get_current_completion(ioat_chan);
547 if (*phys_complete == ioat_chan->last_completion)
548 return false;
549
550 clear_bit(IOAT_COMPLETION_ACK, addr: &ioat_chan->state);
551 mod_timer(timer: &ioat_chan->timer, expires: jiffies + COMPLETION_TIMEOUT);
552
553 return true;
554}
555
556static void
557desc_get_errstat(struct ioatdma_chan *ioat_chan, struct ioat_ring_ent *desc)
558{
559 struct ioat_dma_descriptor *hw = desc->hw;
560
561 switch (hw->ctl_f.op) {
562 case IOAT_OP_PQ_VAL:
563 case IOAT_OP_PQ_VAL_16S:
564 {
565 struct ioat_pq_descriptor *pq = desc->pq;
566
567 /* check if there's error written */
568 if (!pq->dwbes_f.wbes)
569 return;
570
571 /* need to set a chanerr var for checking to clear later */
572
573 if (pq->dwbes_f.p_val_err)
574 *desc->result |= SUM_CHECK_P_RESULT;
575
576 if (pq->dwbes_f.q_val_err)
577 *desc->result |= SUM_CHECK_Q_RESULT;
578
579 return;
580 }
581 default:
582 return;
583 }
584}
585
586/**
587 * __ioat_cleanup - reclaim used descriptors
588 * @ioat_chan: channel (ring) to clean
589 * @phys_complete: zeroed (or not) completion address (from status)
590 */
591static void __ioat_cleanup(struct ioatdma_chan *ioat_chan, dma_addr_t phys_complete)
592{
593 struct ioatdma_device *ioat_dma = ioat_chan->ioat_dma;
594 struct ioat_ring_ent *desc;
595 bool seen_current = false;
596 int idx = ioat_chan->tail, i;
597 u16 active;
598
599 dev_dbg(to_dev(ioat_chan), "%s: head: %#x tail: %#x issued: %#x\n",
600 __func__, ioat_chan->head, ioat_chan->tail, ioat_chan->issued);
601
602 /*
603 * At restart of the channel, the completion address and the
604 * channel status will be 0 due to starting a new chain. Since
605 * it's new chain and the first descriptor "fails", there is
606 * nothing to clean up. We do not want to reap the entire submitted
607 * chain due to this 0 address value and then BUG.
608 */
609 if (!phys_complete)
610 return;
611
612 active = ioat_ring_active(ioat_chan);
613 for (i = 0; i < active && !seen_current; i++) {
614 struct dma_async_tx_descriptor *tx;
615
616 prefetch(ioat_get_ring_ent(ioat_chan, idx + i + 1));
617 desc = ioat_get_ring_ent(ioat_chan, idx: idx + i);
618 dump_desc_dbg(ioat_chan, desc);
619
620 /* set err stat if we are using dwbes */
621 if (ioat_dma->cap & IOAT_CAP_DWBES)
622 desc_get_errstat(ioat_chan, desc);
623
624 tx = &desc->txd;
625 if (tx->cookie) {
626 dma_cookie_complete(tx);
627 dma_descriptor_unmap(tx);
628 dmaengine_desc_get_callback_invoke(tx, NULL);
629 tx->callback = NULL;
630 tx->callback_result = NULL;
631 }
632
633 if (tx->phys == phys_complete)
634 seen_current = true;
635
636 /* skip extended descriptors */
637 if (desc_has_ext(desc)) {
638 BUG_ON(i + 1 >= active);
639 i++;
640 }
641
642 /* cleanup super extended descriptors */
643 if (desc->sed) {
644 ioat_free_sed(ioat_dma, sed: desc->sed);
645 desc->sed = NULL;
646 }
647 }
648
649 /* finish all descriptor reads before incrementing tail */
650 smp_mb();
651 ioat_chan->tail = idx + i;
652 /* no active descs have written a completion? */
653 BUG_ON(active && !seen_current);
654 ioat_chan->last_completion = phys_complete;
655
656 if (active - i == 0) {
657 dev_dbg(to_dev(ioat_chan), "%s: cancel completion timeout\n",
658 __func__);
659 mod_timer_pending(timer: &ioat_chan->timer, expires: jiffies + IDLE_TIMEOUT);
660 }
661
662 /* microsecond delay by sysfs variable per pending descriptor */
663 if (ioat_chan->intr_coalesce != ioat_chan->prev_intr_coalesce) {
664 writew(min((ioat_chan->intr_coalesce * (active - i)),
665 IOAT_INTRDELAY_MASK),
666 addr: ioat_chan->ioat_dma->reg_base + IOAT_INTRDELAY_OFFSET);
667 ioat_chan->prev_intr_coalesce = ioat_chan->intr_coalesce;
668 }
669}
670
671static void ioat_cleanup(struct ioatdma_chan *ioat_chan)
672{
673 u64 phys_complete;
674
675 spin_lock_bh(lock: &ioat_chan->cleanup_lock);
676
677 if (ioat_cleanup_preamble(ioat_chan, phys_complete: &phys_complete))
678 __ioat_cleanup(ioat_chan, phys_complete);
679
680 if (is_ioat_halted(status: *ioat_chan->completion)) {
681 u32 chanerr = readl(addr: ioat_chan->reg_base + IOAT_CHANERR_OFFSET);
682
683 if (chanerr &
684 (IOAT_CHANERR_HANDLE_MASK | IOAT_CHANERR_RECOVER_MASK)) {
685 mod_timer_pending(timer: &ioat_chan->timer, expires: jiffies + IDLE_TIMEOUT);
686 ioat_eh(ioat_chan);
687 }
688 }
689
690 spin_unlock_bh(lock: &ioat_chan->cleanup_lock);
691}
692
693void ioat_cleanup_event(struct tasklet_struct *t)
694{
695 struct ioatdma_chan *ioat_chan = from_tasklet(ioat_chan, t, cleanup_task);
696
697 ioat_cleanup(ioat_chan);
698 if (!test_bit(IOAT_RUN, &ioat_chan->state))
699 return;
700 writew(IOAT_CHANCTRL_RUN, addr: ioat_chan->reg_base + IOAT_CHANCTRL_OFFSET);
701}
702
703static void ioat_restart_channel(struct ioatdma_chan *ioat_chan)
704{
705 u64 phys_complete;
706
707 /* set the completion address register again */
708 writel(lower_32_bits(ioat_chan->completion_dma),
709 addr: ioat_chan->reg_base + IOAT_CHANCMP_OFFSET_LOW);
710 writel(upper_32_bits(ioat_chan->completion_dma),
711 addr: ioat_chan->reg_base + IOAT_CHANCMP_OFFSET_HIGH);
712
713 ioat_quiesce(ioat_chan, tmo: 0);
714 if (ioat_cleanup_preamble(ioat_chan, phys_complete: &phys_complete))
715 __ioat_cleanup(ioat_chan, phys_complete);
716
717 __ioat_restart_chan(ioat_chan);
718}
719
720
721static void ioat_abort_descs(struct ioatdma_chan *ioat_chan)
722{
723 struct ioatdma_device *ioat_dma = ioat_chan->ioat_dma;
724 struct ioat_ring_ent *desc;
725 u16 active;
726 int idx = ioat_chan->tail, i;
727
728 /*
729 * We assume that the failed descriptor has been processed.
730 * Now we are just returning all the remaining submitted
731 * descriptors to abort.
732 */
733 active = ioat_ring_active(ioat_chan);
734
735 /* we skip the failed descriptor that tail points to */
736 for (i = 1; i < active; i++) {
737 struct dma_async_tx_descriptor *tx;
738
739 prefetch(ioat_get_ring_ent(ioat_chan, idx + i + 1));
740 desc = ioat_get_ring_ent(ioat_chan, idx: idx + i);
741
742 tx = &desc->txd;
743 if (tx->cookie) {
744 struct dmaengine_result res;
745
746 dma_cookie_complete(tx);
747 dma_descriptor_unmap(tx);
748 res.result = DMA_TRANS_ABORTED;
749 dmaengine_desc_get_callback_invoke(tx, result: &res);
750 tx->callback = NULL;
751 tx->callback_result = NULL;
752 }
753
754 /* skip extended descriptors */
755 if (desc_has_ext(desc)) {
756 WARN_ON(i + 1 >= active);
757 i++;
758 }
759
760 /* cleanup super extended descriptors */
761 if (desc->sed) {
762 ioat_free_sed(ioat_dma, sed: desc->sed);
763 desc->sed = NULL;
764 }
765 }
766
767 smp_mb(); /* finish all descriptor reads before incrementing tail */
768 ioat_chan->tail = idx + active;
769
770 desc = ioat_get_ring_ent(ioat_chan, idx: ioat_chan->tail);
771 ioat_chan->last_completion = *ioat_chan->completion = desc->txd.phys;
772}
773
774static void ioat_eh(struct ioatdma_chan *ioat_chan)
775{
776 struct pci_dev *pdev = to_pdev(ioat_chan);
777 struct ioat_dma_descriptor *hw;
778 struct dma_async_tx_descriptor *tx;
779 u64 phys_complete;
780 struct ioat_ring_ent *desc;
781 u32 err_handled = 0;
782 u32 chanerr_int;
783 u32 chanerr;
784 bool abort = false;
785 struct dmaengine_result res;
786
787 /* cleanup so tail points to descriptor that caused the error */
788 if (ioat_cleanup_preamble(ioat_chan, phys_complete: &phys_complete))
789 __ioat_cleanup(ioat_chan, phys_complete);
790
791 chanerr = readl(addr: ioat_chan->reg_base + IOAT_CHANERR_OFFSET);
792 pci_read_config_dword(dev: pdev, IOAT_PCI_CHANERR_INT_OFFSET, val: &chanerr_int);
793
794 dev_dbg(to_dev(ioat_chan), "%s: error = %x:%x\n",
795 __func__, chanerr, chanerr_int);
796
797 desc = ioat_get_ring_ent(ioat_chan, idx: ioat_chan->tail);
798 hw = desc->hw;
799 dump_desc_dbg(ioat_chan, desc);
800
801 switch (hw->ctl_f.op) {
802 case IOAT_OP_XOR_VAL:
803 if (chanerr & IOAT_CHANERR_XOR_P_OR_CRC_ERR) {
804 *desc->result |= SUM_CHECK_P_RESULT;
805 err_handled |= IOAT_CHANERR_XOR_P_OR_CRC_ERR;
806 }
807 break;
808 case IOAT_OP_PQ_VAL:
809 case IOAT_OP_PQ_VAL_16S:
810 if (chanerr & IOAT_CHANERR_XOR_P_OR_CRC_ERR) {
811 *desc->result |= SUM_CHECK_P_RESULT;
812 err_handled |= IOAT_CHANERR_XOR_P_OR_CRC_ERR;
813 }
814 if (chanerr & IOAT_CHANERR_XOR_Q_ERR) {
815 *desc->result |= SUM_CHECK_Q_RESULT;
816 err_handled |= IOAT_CHANERR_XOR_Q_ERR;
817 }
818 break;
819 }
820
821 if (chanerr & IOAT_CHANERR_RECOVER_MASK) {
822 if (chanerr & IOAT_CHANERR_READ_DATA_ERR) {
823 res.result = DMA_TRANS_READ_FAILED;
824 err_handled |= IOAT_CHANERR_READ_DATA_ERR;
825 } else if (chanerr & IOAT_CHANERR_WRITE_DATA_ERR) {
826 res.result = DMA_TRANS_WRITE_FAILED;
827 err_handled |= IOAT_CHANERR_WRITE_DATA_ERR;
828 }
829
830 abort = true;
831 } else
832 res.result = DMA_TRANS_NOERROR;
833
834 /* fault on unhandled error or spurious halt */
835 if (chanerr ^ err_handled || chanerr == 0) {
836 dev_err(to_dev(ioat_chan), "%s: fatal error (%x:%x)\n",
837 __func__, chanerr, err_handled);
838 dev_err(to_dev(ioat_chan), "Errors handled:\n");
839 ioat_print_chanerrs(ioat_chan, chanerr: err_handled);
840 dev_err(to_dev(ioat_chan), "Errors not handled:\n");
841 ioat_print_chanerrs(ioat_chan, chanerr: (chanerr & ~err_handled));
842
843 BUG();
844 }
845
846 /* cleanup the faulty descriptor since we are continuing */
847 tx = &desc->txd;
848 if (tx->cookie) {
849 dma_cookie_complete(tx);
850 dma_descriptor_unmap(tx);
851 dmaengine_desc_get_callback_invoke(tx, result: &res);
852 tx->callback = NULL;
853 tx->callback_result = NULL;
854 }
855
856 /* mark faulting descriptor as complete */
857 *ioat_chan->completion = desc->txd.phys;
858
859 spin_lock_bh(lock: &ioat_chan->prep_lock);
860 /* we need abort all descriptors */
861 if (abort) {
862 ioat_abort_descs(ioat_chan);
863 /* clean up the channel, we could be in weird state */
864 ioat_reset_hw(ioat_chan);
865 }
866
867 writel(val: chanerr, addr: ioat_chan->reg_base + IOAT_CHANERR_OFFSET);
868 pci_write_config_dword(dev: pdev, IOAT_PCI_CHANERR_INT_OFFSET, val: chanerr_int);
869
870 ioat_restart_channel(ioat_chan);
871 spin_unlock_bh(lock: &ioat_chan->prep_lock);
872}
873
874static void check_active(struct ioatdma_chan *ioat_chan)
875{
876 if (ioat_ring_active(ioat_chan)) {
877 mod_timer(timer: &ioat_chan->timer, expires: jiffies + COMPLETION_TIMEOUT);
878 return;
879 }
880
881 if (test_and_clear_bit(IOAT_CHAN_ACTIVE, addr: &ioat_chan->state))
882 mod_timer_pending(timer: &ioat_chan->timer, expires: jiffies + IDLE_TIMEOUT);
883}
884
885static void ioat_reboot_chan(struct ioatdma_chan *ioat_chan)
886{
887 spin_lock_bh(lock: &ioat_chan->prep_lock);
888 set_bit(IOAT_CHAN_DOWN, addr: &ioat_chan->state);
889 spin_unlock_bh(lock: &ioat_chan->prep_lock);
890
891 ioat_abort_descs(ioat_chan);
892 dev_warn(to_dev(ioat_chan), "Reset channel...\n");
893 ioat_reset_hw(ioat_chan);
894 dev_warn(to_dev(ioat_chan), "Restart channel...\n");
895 ioat_restart_channel(ioat_chan);
896
897 spin_lock_bh(lock: &ioat_chan->prep_lock);
898 clear_bit(IOAT_CHAN_DOWN, addr: &ioat_chan->state);
899 spin_unlock_bh(lock: &ioat_chan->prep_lock);
900}
901
902void ioat_timer_event(struct timer_list *t)
903{
904 struct ioatdma_chan *ioat_chan = from_timer(ioat_chan, t, timer);
905 dma_addr_t phys_complete;
906 u64 status;
907
908 status = ioat_chansts(ioat_chan);
909
910 /* when halted due to errors check for channel
911 * programming errors before advancing the completion state
912 */
913 if (is_ioat_halted(status)) {
914 u32 chanerr;
915
916 chanerr = readl(addr: ioat_chan->reg_base + IOAT_CHANERR_OFFSET);
917 dev_err(to_dev(ioat_chan), "%s: Channel halted (%x)\n",
918 __func__, chanerr);
919 dev_err(to_dev(ioat_chan), "Errors:\n");
920 ioat_print_chanerrs(ioat_chan, chanerr);
921
922 if (test_bit(IOAT_RUN, &ioat_chan->state)) {
923 spin_lock_bh(lock: &ioat_chan->cleanup_lock);
924 ioat_reboot_chan(ioat_chan);
925 spin_unlock_bh(lock: &ioat_chan->cleanup_lock);
926 }
927
928 return;
929 }
930
931 spin_lock_bh(lock: &ioat_chan->cleanup_lock);
932
933 /* handle the no-actives case */
934 if (!ioat_ring_active(ioat_chan)) {
935 spin_lock_bh(lock: &ioat_chan->prep_lock);
936 check_active(ioat_chan);
937 spin_unlock_bh(lock: &ioat_chan->prep_lock);
938 goto unlock_out;
939 }
940
941 /* handle the missed cleanup case */
942 if (ioat_cleanup_preamble(ioat_chan, phys_complete: &phys_complete)) {
943 /* timer restarted in ioat_cleanup_preamble
944 * and IOAT_COMPLETION_ACK cleared
945 */
946 __ioat_cleanup(ioat_chan, phys_complete);
947 goto unlock_out;
948 }
949
950 /* if we haven't made progress and we have already
951 * acknowledged a pending completion once, then be more
952 * forceful with a restart
953 */
954 if (test_bit(IOAT_COMPLETION_ACK, &ioat_chan->state)) {
955 u32 chanerr;
956
957 chanerr = readl(addr: ioat_chan->reg_base + IOAT_CHANERR_OFFSET);
958 dev_err(to_dev(ioat_chan), "CHANSTS: %#Lx CHANERR: %#x\n",
959 status, chanerr);
960 dev_err(to_dev(ioat_chan), "Errors:\n");
961 ioat_print_chanerrs(ioat_chan, chanerr);
962
963 dev_dbg(to_dev(ioat_chan), "Active descriptors: %d\n",
964 ioat_ring_active(ioat_chan));
965
966 ioat_reboot_chan(ioat_chan);
967
968 goto unlock_out;
969 }
970
971 /* handle missed issue pending case */
972 if (ioat_ring_pending(ioat_chan)) {
973 dev_warn(to_dev(ioat_chan),
974 "Completion timeout with pending descriptors\n");
975 spin_lock_bh(lock: &ioat_chan->prep_lock);
976 __ioat_issue_pending(ioat_chan);
977 spin_unlock_bh(lock: &ioat_chan->prep_lock);
978 }
979
980 set_bit(IOAT_COMPLETION_ACK, addr: &ioat_chan->state);
981 mod_timer(timer: &ioat_chan->timer, expires: jiffies + COMPLETION_TIMEOUT);
982unlock_out:
983 spin_unlock_bh(lock: &ioat_chan->cleanup_lock);
984}
985
986enum dma_status
987ioat_tx_status(struct dma_chan *c, dma_cookie_t cookie,
988 struct dma_tx_state *txstate)
989{
990 struct ioatdma_chan *ioat_chan = to_ioat_chan(c);
991 enum dma_status ret;
992
993 ret = dma_cookie_status(chan: c, cookie, state: txstate);
994 if (ret == DMA_COMPLETE)
995 return ret;
996
997 ioat_cleanup(ioat_chan);
998
999 return dma_cookie_status(chan: c, cookie, state: txstate);
1000}
1001
1002int ioat_reset_hw(struct ioatdma_chan *ioat_chan)
1003{
1004 /* throw away whatever the channel was doing and get it
1005 * initialized, with ioat3 specific workarounds
1006 */
1007 struct ioatdma_device *ioat_dma = ioat_chan->ioat_dma;
1008 struct pci_dev *pdev = ioat_dma->pdev;
1009 u32 chanerr;
1010 u16 dev_id;
1011 int err;
1012
1013 ioat_quiesce(ioat_chan, tmo: msecs_to_jiffies(m: 100));
1014
1015 chanerr = readl(addr: ioat_chan->reg_base + IOAT_CHANERR_OFFSET);
1016 writel(val: chanerr, addr: ioat_chan->reg_base + IOAT_CHANERR_OFFSET);
1017
1018 if (ioat_dma->version < IOAT_VER_3_3) {
1019 /* clear any pending errors */
1020 err = pci_read_config_dword(dev: pdev,
1021 IOAT_PCI_CHANERR_INT_OFFSET, val: &chanerr);
1022 if (err) {
1023 dev_err(&pdev->dev,
1024 "channel error register unreachable\n");
1025 return err;
1026 }
1027 pci_write_config_dword(dev: pdev,
1028 IOAT_PCI_CHANERR_INT_OFFSET, val: chanerr);
1029
1030 /* Clear DMAUNCERRSTS Cfg-Reg Parity Error status bit
1031 * (workaround for spurious config parity error after restart)
1032 */
1033 pci_read_config_word(dev: pdev, IOAT_PCI_DEVICE_ID_OFFSET, val: &dev_id);
1034 if (dev_id == PCI_DEVICE_ID_INTEL_IOAT_TBG0) {
1035 pci_write_config_dword(dev: pdev,
1036 IOAT_PCI_DMAUNCERRSTS_OFFSET,
1037 val: 0x10);
1038 }
1039 }
1040
1041 if (is_bwd_ioat(pdev) && (ioat_dma->irq_mode == IOAT_MSIX)) {
1042 ioat_dma->msixtba0 = readq(addr: ioat_dma->reg_base + 0x1000);
1043 ioat_dma->msixdata0 = readq(addr: ioat_dma->reg_base + 0x1008);
1044 ioat_dma->msixpba = readq(addr: ioat_dma->reg_base + 0x1800);
1045 }
1046
1047
1048 err = ioat_reset_sync(ioat_chan, tmo: msecs_to_jiffies(m: 200));
1049 if (!err) {
1050 if (is_bwd_ioat(pdev) && (ioat_dma->irq_mode == IOAT_MSIX)) {
1051 writeq(val: ioat_dma->msixtba0, addr: ioat_dma->reg_base + 0x1000);
1052 writeq(val: ioat_dma->msixdata0, addr: ioat_dma->reg_base + 0x1008);
1053 writeq(val: ioat_dma->msixpba, addr: ioat_dma->reg_base + 0x1800);
1054 }
1055 }
1056
1057 if (err)
1058 dev_err(&pdev->dev, "Failed to reset: %d\n", err);
1059
1060 return err;
1061}
1062

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