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(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(intrctrl, instance->reg_base + IOAT_INTRCTRL_OFFSET);
106		return IRQ_NONE;
107	}
108
109	attnstatus = readl(instance->reg_base + IOAT_ATTNSTATUS_OFFSET);
110	for_each_set_bit(bit, &attnstatus, BITS_PER_LONG) {
111		ioat_chan = ioat_chan_by_index(instance, bit);
112		if (test_bit(IOAT_RUN, &ioat_chan->state))
113			tasklet_schedule(&ioat_chan->cleanup_task);
114	}
115
116	writeb(intrctrl, 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(&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, &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(msix->vector);
152		break;
153	case IOAT_MSI:
154	case IOAT_INTX:
155		synchronize_irq(pdev->irq);
156		break;
157	default:
158		break;
159	}
160
161	/* flush inflight timers */
162	del_timer_sync(&ioat_chan->timer);
163
164	/* flush inflight tasklet runs */
165	tasklet_kill(&ioat_chan->cleanup_task);
166
167	/* final cleanup now that everything is quiesced and can't re-arm */
168	ioat_cleanup_event(&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(ioat_chan->dmacount,
176	       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(&ioat_chan->prep_lock);
189		__ioat_issue_pending(ioat_chan);
190		spin_unlock_bh(&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, 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(&desc->txd);
233	ioat_set_chainaddr(ioat_chan, 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(&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(&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(&ioat_chan->timer, 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, ioat_chan->tail);
265		ioat_set_chainaddr(ioat_chan, 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, &ioat_chan->state))
320		mod_timer(&ioat_chan->timer, 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(&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(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(ioat_cache, flags);
356	if (!desc)
357		return NULL;
358
359	dma_async_tx_descriptor_init(&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(ioat_cache, 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(total_descs, 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, &descs->hw, 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						descs->virt, descs->hw);
401				descs->virt = NULL;
402				descs->hw = 0;
403			}
404
405			ioat_chan->desc_chunks = 0;
406			kfree(ring);
407			return NULL;
408		}
409	}
410
411	for (i = 0; i < total_descs; i++) {
412		ring[i] = ioat_alloc_ring_ent(c, i, flags);
413		if (!ring[i]) {
414			int idx;
415
416			while (i--)
417				ioat_free_ring_ent(ring[i], 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						  ioat_chan->descs[idx].virt,
423						  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(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(drsctl, 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(&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(&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(&ioat_chan->timer)) {
491		mod_timer(&ioat_chan->timer, jiffies + COMPLETION_TIMEOUT);
492		ioat_timer_event(&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(ioat_dma->sed_hw_pool[sed->hw_pool], sed->hw, sed->dma);
526	kmem_cache_free(ioat_sed_cache, 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(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, &ioat_chan->state);
551	mod_timer(&ioat_chan->timer, 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 + 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, 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(&ioat_chan->timer, 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		       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(&ioat_chan->cleanup_lock);
676
677	if (ioat_cleanup_preamble(ioat_chan, &phys_complete))
678		__ioat_cleanup(ioat_chan, phys_complete);
679
680	if (is_ioat_halted(*ioat_chan->completion)) {
681		u32 chanerr = readl(ioat_chan->reg_base + IOAT_CHANERR_OFFSET);
682
683		if (chanerr &
684		    (IOAT_CHANERR_HANDLE_MASK | IOAT_CHANERR_RECOVER_MASK)) {
685			mod_timer_pending(&ioat_chan->timer, jiffies + IDLE_TIMEOUT);
686			ioat_eh(ioat_chan);
687		}
688	}
689
690	spin_unlock_bh(&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, 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	       ioat_chan->reg_base + IOAT_CHANCMP_OFFSET_LOW);
710	writel(upper_32_bits(ioat_chan->completion_dma),
711	       ioat_chan->reg_base + IOAT_CHANCMP_OFFSET_HIGH);
712
713	ioat_quiesce(ioat_chan, 0);
714	if (ioat_cleanup_preamble(ioat_chan, &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 + 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, &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, 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, 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))
789		__ioat_cleanup(ioat_chan, phys_complete);
790
791	chanerr = readl(ioat_chan->reg_base + IOAT_CHANERR_OFFSET);
792	pci_read_config_dword(pdev, IOAT_PCI_CHANERR_INT_OFFSET, &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, 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, err_handled);
840		dev_err(to_dev(ioat_chan), "Errors not handled:\n");
841		ioat_print_chanerrs(ioat_chan, (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, &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(&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(chanerr, ioat_chan->reg_base + IOAT_CHANERR_OFFSET);
868	pci_write_config_dword(pdev, IOAT_PCI_CHANERR_INT_OFFSET, chanerr_int);
869
870	ioat_restart_channel(ioat_chan);
871	spin_unlock_bh(&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(&ioat_chan->timer, jiffies + COMPLETION_TIMEOUT);
878		return;
879	}
880
881	if (test_and_clear_bit(IOAT_CHAN_ACTIVE, &ioat_chan->state))
882		mod_timer_pending(&ioat_chan->timer, jiffies + IDLE_TIMEOUT);
883}
884
885static void ioat_reboot_chan(struct ioatdma_chan *ioat_chan)
886{
887	spin_lock_bh(&ioat_chan->prep_lock);
888	set_bit(IOAT_CHAN_DOWN, &ioat_chan->state);
889	spin_unlock_bh(&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(&ioat_chan->prep_lock);
898	clear_bit(IOAT_CHAN_DOWN, &ioat_chan->state);
899	spin_unlock_bh(&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(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(&ioat_chan->cleanup_lock);
924			ioat_reboot_chan(ioat_chan);
925			spin_unlock_bh(&ioat_chan->cleanup_lock);
926		}
927
928		return;
929	}
930
931	spin_lock_bh(&ioat_chan->cleanup_lock);
932
933	/* handle the no-actives case */
934	if (!ioat_ring_active(ioat_chan)) {
935		spin_lock_bh(&ioat_chan->prep_lock);
936		check_active(ioat_chan);
937		spin_unlock_bh(&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)) {
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(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(&ioat_chan->prep_lock);
976		__ioat_issue_pending(ioat_chan);
977		spin_unlock_bh(&ioat_chan->prep_lock);
978	}
979
980	set_bit(IOAT_COMPLETION_ACK, &ioat_chan->state);
981	mod_timer(&ioat_chan->timer, jiffies + COMPLETION_TIMEOUT);
982unlock_out:
983	spin_unlock_bh(&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(c, cookie, txstate);
994	if (ret == DMA_COMPLETE)
995		return ret;
996
997	ioat_cleanup(ioat_chan);
998
999	return dma_cookie_status(c, cookie, 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, msecs_to_jiffies(100));
1014
1015	chanerr = readl(ioat_chan->reg_base + IOAT_CHANERR_OFFSET);
1016	writel(chanerr, 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(pdev,
1021				IOAT_PCI_CHANERR_INT_OFFSET, &chanerr);
1022		if (err) {
1023			dev_err(&pdev->dev,
1024				"channel error register unreachable\n");
1025			return err;
1026		}
1027		pci_write_config_dword(pdev,
1028				IOAT_PCI_CHANERR_INT_OFFSET, 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(pdev, IOAT_PCI_DEVICE_ID_OFFSET, &dev_id);
1034		if (dev_id == PCI_DEVICE_ID_INTEL_IOAT_TBG0) {
1035			pci_write_config_dword(pdev,
1036					       IOAT_PCI_DMAUNCERRSTS_OFFSET,
1037					       0x10);
1038		}
1039	}
1040
1041	if (is_bwd_ioat(pdev) && (ioat_dma->irq_mode == IOAT_MSIX)) {
1042		ioat_dma->msixtba0 = readq(ioat_dma->reg_base + 0x1000);
1043		ioat_dma->msixdata0 = readq(ioat_dma->reg_base + 0x1008);
1044		ioat_dma->msixpba = readq(ioat_dma->reg_base + 0x1800);
1045	}
1046
1047
1048	err = ioat_reset_sync(ioat_chan, msecs_to_jiffies(200));
1049	if (!err) {
1050		if (is_bwd_ioat(pdev) && (ioat_dma->irq_mode == IOAT_MSIX)) {
1051			writeq(ioat_dma->msixtba0, ioat_dma->reg_base + 0x1000);
1052			writeq(ioat_dma->msixdata0, ioat_dma->reg_base + 0x1008);
1053			writeq(ioat_dma->msixpba, 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