2 * Intel I/OAT DMA Linux driver
3 * Copyright(c) 2004 - 2009 Intel Corporation.
5 * This program is free software; you can redistribute it and/or modify it
6 * under the terms and conditions of the GNU General Public License,
7 * version 2, as published by the Free Software Foundation.
9 * This program is distributed in the hope that it will be useful, but WITHOUT
10 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
11 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
14 * You should have received a copy of the GNU General Public License along with
15 * this program; if not, write to the Free Software Foundation, Inc.,
16 * 51 Franklin St - Fifth Floor, Boston, MA 02110-1301 USA.
18 * The full GNU General Public License is included in this distribution in
19 * the file called "COPYING".
24 * This driver supports an Intel I/OAT DMA engine, which does asynchronous
28 #include <linux/init.h>
29 #include <linux/module.h>
30 #include <linux/pci.h>
31 #include <linux/interrupt.h>
32 #include <linux/dmaengine.h>
33 #include <linux/delay.h>
34 #include <linux/dma-mapping.h>
35 #include <linux/workqueue.h>
36 #include <linux/i7300_idle.h>
38 #include "registers.h"
41 int ioat_pending_level = 4;
42 module_param(ioat_pending_level, int, 0644);
43 MODULE_PARM_DESC(ioat_pending_level,
44 "high-water mark for pushing ioat descriptors (default: 4)");
46 /* internal functions */
47 static void ioat1_cleanup(struct ioat_dma_chan *ioat);
48 static void ioat1_dma_start_null_desc(struct ioat_dma_chan *ioat);
51 * ioat_dma_do_interrupt - handler used for single vector interrupt mode
53 * @data: interrupt data
55 static irqreturn_t ioat_dma_do_interrupt(int irq, void *data)
57 struct ioatdma_device *instance = data;
58 struct ioat_chan_common *chan;
59 unsigned long attnstatus;
63 intrctrl = readb(instance->reg_base + IOAT_INTRCTRL_OFFSET);
65 if (!(intrctrl & IOAT_INTRCTRL_MASTER_INT_EN))
68 if (!(intrctrl & IOAT_INTRCTRL_INT_STATUS)) {
69 writeb(intrctrl, instance->reg_base + IOAT_INTRCTRL_OFFSET);
73 attnstatus = readl(instance->reg_base + IOAT_ATTNSTATUS_OFFSET);
74 for_each_bit(bit, &attnstatus, BITS_PER_LONG) {
75 chan = ioat_chan_by_index(instance, bit);
76 tasklet_schedule(&chan->cleanup_task);
79 writeb(intrctrl, instance->reg_base + IOAT_INTRCTRL_OFFSET);
84 * ioat_dma_do_interrupt_msix - handler used for vector-per-channel interrupt mode
86 * @data: interrupt data
88 static irqreturn_t ioat_dma_do_interrupt_msix(int irq, void *data)
90 struct ioat_chan_common *chan = data;
92 tasklet_schedule(&chan->cleanup_task);
97 static void ioat1_cleanup_tasklet(unsigned long data);
99 /* common channel initialization */
100 void ioat_init_channel(struct ioatdma_device *device,
101 struct ioat_chan_common *chan, int idx,
102 void (*timer_fn)(unsigned long),
103 void (*tasklet)(unsigned long),
106 struct dma_device *dma = &device->common;
108 chan->device = device;
109 chan->reg_base = device->reg_base + (0x80 * (idx + 1));
110 spin_lock_init(&chan->cleanup_lock);
111 chan->common.device = dma;
112 list_add_tail(&chan->common.device_node, &dma->channels);
113 device->idx[idx] = chan;
114 init_timer(&chan->timer);
115 chan->timer.function = timer_fn;
116 chan->timer.data = ioat;
117 tasklet_init(&chan->cleanup_task, tasklet, ioat);
118 tasklet_disable(&chan->cleanup_task);
121 static void ioat1_timer_event(unsigned long data);
124 * ioat1_dma_enumerate_channels - find and initialize the device's channels
125 * @device: the device to be enumerated
127 static int ioat1_enumerate_channels(struct ioatdma_device *device)
132 struct ioat_dma_chan *ioat;
133 struct device *dev = &device->pdev->dev;
134 struct dma_device *dma = &device->common;
136 INIT_LIST_HEAD(&dma->channels);
137 dma->chancnt = readb(device->reg_base + IOAT_CHANCNT_OFFSET);
138 dma->chancnt &= 0x1f; /* bits [4:0] valid */
139 if (dma->chancnt > ARRAY_SIZE(device->idx)) {
140 dev_warn(dev, "(%d) exceeds max supported channels (%zu)\n",
141 dma->chancnt, ARRAY_SIZE(device->idx));
142 dma->chancnt = ARRAY_SIZE(device->idx);
144 xfercap_scale = readb(device->reg_base + IOAT_XFERCAP_OFFSET);
145 xfercap_scale &= 0x1f; /* bits [4:0] valid */
146 xfercap = (xfercap_scale == 0 ? -1 : (1UL << xfercap_scale));
147 dev_dbg(dev, "%s: xfercap = %d\n", __func__, xfercap);
149 #ifdef CONFIG_I7300_IDLE_IOAT_CHANNEL
150 if (i7300_idle_platform_probe(NULL, NULL, 1) == 0)
153 for (i = 0; i < dma->chancnt; i++) {
154 ioat = devm_kzalloc(dev, sizeof(*ioat), GFP_KERNEL);
158 ioat_init_channel(device, &ioat->base, i,
160 ioat1_cleanup_tasklet,
161 (unsigned long) ioat);
162 ioat->xfercap = xfercap;
163 spin_lock_init(&ioat->desc_lock);
164 INIT_LIST_HEAD(&ioat->free_desc);
165 INIT_LIST_HEAD(&ioat->used_desc);
172 * ioat_dma_memcpy_issue_pending - push potentially unrecognized appended
174 * @chan: DMA channel handle
177 __ioat1_dma_memcpy_issue_pending(struct ioat_dma_chan *ioat)
179 void __iomem *reg_base = ioat->base.reg_base;
181 dev_dbg(to_dev(&ioat->base), "%s: pending: %d\n",
182 __func__, ioat->pending);
184 writeb(IOAT_CHANCMD_APPEND, reg_base + IOAT1_CHANCMD_OFFSET);
187 static void ioat1_dma_memcpy_issue_pending(struct dma_chan *chan)
189 struct ioat_dma_chan *ioat = to_ioat_chan(chan);
191 if (ioat->pending > 0) {
192 spin_lock_bh(&ioat->desc_lock);
193 __ioat1_dma_memcpy_issue_pending(ioat);
194 spin_unlock_bh(&ioat->desc_lock);
199 * ioat1_reset_channel - restart a channel
200 * @ioat: IOAT DMA channel handle
202 static void ioat1_reset_channel(struct ioat_dma_chan *ioat)
204 struct ioat_chan_common *chan = &ioat->base;
205 void __iomem *reg_base = chan->reg_base;
206 u32 chansts, chanerr;
208 dev_warn(to_dev(chan), "reset\n");
209 chanerr = readl(reg_base + IOAT_CHANERR_OFFSET);
210 chansts = *chan->completion & IOAT_CHANSTS_STATUS;
212 dev_err(to_dev(chan),
213 "chan%d, CHANSTS = 0x%08x CHANERR = 0x%04x, clearing\n",
214 chan_num(chan), chansts, chanerr);
215 writel(chanerr, reg_base + IOAT_CHANERR_OFFSET);
219 * whack it upside the head with a reset
220 * and wait for things to settle out.
221 * force the pending count to a really big negative
222 * to make sure no one forces an issue_pending
223 * while we're waiting.
226 ioat->pending = INT_MIN;
227 writeb(IOAT_CHANCMD_RESET,
228 reg_base + IOAT_CHANCMD_OFFSET(chan->device->version));
229 set_bit(IOAT_RESET_PENDING, &chan->state);
230 mod_timer(&chan->timer, jiffies + RESET_DELAY);
233 static dma_cookie_t ioat1_tx_submit(struct dma_async_tx_descriptor *tx)
235 struct dma_chan *c = tx->chan;
236 struct ioat_dma_chan *ioat = to_ioat_chan(c);
237 struct ioat_desc_sw *desc = tx_to_ioat_desc(tx);
238 struct ioat_chan_common *chan = &ioat->base;
239 struct ioat_desc_sw *first;
240 struct ioat_desc_sw *chain_tail;
243 spin_lock_bh(&ioat->desc_lock);
244 /* cookie incr and addition to used_list must be atomic */
251 dev_dbg(to_dev(&ioat->base), "%s: cookie: %d\n", __func__, cookie);
253 /* write address into NextDescriptor field of last desc in chain */
254 first = to_ioat_desc(tx->tx_list.next);
255 chain_tail = to_ioat_desc(ioat->used_desc.prev);
256 /* make descriptor updates globally visible before chaining */
258 chain_tail->hw->next = first->txd.phys;
259 list_splice_tail_init(&tx->tx_list, &ioat->used_desc);
260 dump_desc_dbg(ioat, chain_tail);
261 dump_desc_dbg(ioat, first);
263 if (!test_and_set_bit(IOAT_COMPLETION_PENDING, &chan->state))
264 mod_timer(&chan->timer, jiffies + COMPLETION_TIMEOUT);
266 ioat->pending += desc->hw->tx_cnt;
267 if (ioat->pending >= ioat_pending_level)
268 __ioat1_dma_memcpy_issue_pending(ioat);
269 spin_unlock_bh(&ioat->desc_lock);
275 * ioat_dma_alloc_descriptor - allocate and return a sw and hw descriptor pair
276 * @ioat: the channel supplying the memory pool for the descriptors
277 * @flags: allocation flags
279 static struct ioat_desc_sw *
280 ioat_dma_alloc_descriptor(struct ioat_dma_chan *ioat, gfp_t flags)
282 struct ioat_dma_descriptor *desc;
283 struct ioat_desc_sw *desc_sw;
284 struct ioatdma_device *ioatdma_device;
287 ioatdma_device = ioat->base.device;
288 desc = pci_pool_alloc(ioatdma_device->dma_pool, flags, &phys);
292 desc_sw = kzalloc(sizeof(*desc_sw), flags);
293 if (unlikely(!desc_sw)) {
294 pci_pool_free(ioatdma_device->dma_pool, desc, phys);
298 memset(desc, 0, sizeof(*desc));
300 dma_async_tx_descriptor_init(&desc_sw->txd, &ioat->base.common);
301 desc_sw->txd.tx_submit = ioat1_tx_submit;
303 desc_sw->txd.phys = phys;
304 set_desc_id(desc_sw, -1);
309 static int ioat_initial_desc_count = 256;
310 module_param(ioat_initial_desc_count, int, 0644);
311 MODULE_PARM_DESC(ioat_initial_desc_count,
312 "ioat1: initial descriptors per channel (default: 256)");
314 * ioat1_dma_alloc_chan_resources - returns the number of allocated descriptors
315 * @chan: the channel to be filled out
317 static int ioat1_dma_alloc_chan_resources(struct dma_chan *c)
319 struct ioat_dma_chan *ioat = to_ioat_chan(c);
320 struct ioat_chan_common *chan = &ioat->base;
321 struct ioat_desc_sw *desc;
326 /* have we already been set up? */
327 if (!list_empty(&ioat->free_desc))
328 return ioat->desccount;
330 /* Setup register to interrupt and write completion status on error */
331 writew(IOAT_CHANCTRL_RUN, chan->reg_base + IOAT_CHANCTRL_OFFSET);
333 chanerr = readl(chan->reg_base + IOAT_CHANERR_OFFSET);
335 dev_err(to_dev(chan), "CHANERR = %x, clearing\n", chanerr);
336 writel(chanerr, chan->reg_base + IOAT_CHANERR_OFFSET);
339 /* Allocate descriptors */
340 for (i = 0; i < ioat_initial_desc_count; i++) {
341 desc = ioat_dma_alloc_descriptor(ioat, GFP_KERNEL);
343 dev_err(to_dev(chan), "Only %d initial descriptors\n", i);
346 set_desc_id(desc, i);
347 list_add_tail(&desc->node, &tmp_list);
349 spin_lock_bh(&ioat->desc_lock);
351 list_splice(&tmp_list, &ioat->free_desc);
352 spin_unlock_bh(&ioat->desc_lock);
354 /* allocate a completion writeback area */
355 /* doing 2 32bit writes to mmio since 1 64b write doesn't work */
356 chan->completion = pci_pool_alloc(chan->device->completion_pool,
357 GFP_KERNEL, &chan->completion_dma);
358 memset(chan->completion, 0, sizeof(*chan->completion));
359 writel(((u64) chan->completion_dma) & 0x00000000FFFFFFFF,
360 chan->reg_base + IOAT_CHANCMP_OFFSET_LOW);
361 writel(((u64) chan->completion_dma) >> 32,
362 chan->reg_base + IOAT_CHANCMP_OFFSET_HIGH);
364 tasklet_enable(&chan->cleanup_task);
365 ioat1_dma_start_null_desc(ioat); /* give chain to dma device */
366 dev_dbg(to_dev(chan), "%s: allocated %d descriptors\n",
367 __func__, ioat->desccount);
368 return ioat->desccount;
372 * ioat1_dma_free_chan_resources - release all the descriptors
373 * @chan: the channel to be cleaned
375 static void ioat1_dma_free_chan_resources(struct dma_chan *c)
377 struct ioat_dma_chan *ioat = to_ioat_chan(c);
378 struct ioat_chan_common *chan = &ioat->base;
379 struct ioatdma_device *ioatdma_device = chan->device;
380 struct ioat_desc_sw *desc, *_desc;
381 int in_use_descs = 0;
383 /* Before freeing channel resources first check
384 * if they have been previously allocated for this channel.
386 if (ioat->desccount == 0)
389 tasklet_disable(&chan->cleanup_task);
390 del_timer_sync(&chan->timer);
393 /* Delay 100ms after reset to allow internal DMA logic to quiesce
394 * before removing DMA descriptor resources.
396 writeb(IOAT_CHANCMD_RESET,
397 chan->reg_base + IOAT_CHANCMD_OFFSET(chan->device->version));
400 spin_lock_bh(&ioat->desc_lock);
401 list_for_each_entry_safe(desc, _desc, &ioat->used_desc, node) {
402 dev_dbg(to_dev(chan), "%s: freeing %d from used list\n",
403 __func__, desc_id(desc));
404 dump_desc_dbg(ioat, desc);
406 list_del(&desc->node);
407 pci_pool_free(ioatdma_device->dma_pool, desc->hw,
411 list_for_each_entry_safe(desc, _desc,
412 &ioat->free_desc, node) {
413 list_del(&desc->node);
414 pci_pool_free(ioatdma_device->dma_pool, desc->hw,
418 spin_unlock_bh(&ioat->desc_lock);
420 pci_pool_free(ioatdma_device->completion_pool,
422 chan->completion_dma);
424 /* one is ok since we left it on there on purpose */
425 if (in_use_descs > 1)
426 dev_err(to_dev(chan), "Freeing %d in use descriptors!\n",
429 chan->last_completion = 0;
430 chan->completion_dma = 0;
436 * ioat1_dma_get_next_descriptor - return the next available descriptor
437 * @ioat: IOAT DMA channel handle
439 * Gets the next descriptor from the chain, and must be called with the
440 * channel's desc_lock held. Allocates more descriptors if the channel
443 static struct ioat_desc_sw *
444 ioat1_dma_get_next_descriptor(struct ioat_dma_chan *ioat)
446 struct ioat_desc_sw *new;
448 if (!list_empty(&ioat->free_desc)) {
449 new = to_ioat_desc(ioat->free_desc.next);
450 list_del(&new->node);
452 /* try to get another desc */
453 new = ioat_dma_alloc_descriptor(ioat, GFP_ATOMIC);
455 dev_err(to_dev(&ioat->base), "alloc failed\n");
459 dev_dbg(to_dev(&ioat->base), "%s: allocated: %d\n",
460 __func__, desc_id(new));
465 static struct dma_async_tx_descriptor *
466 ioat1_dma_prep_memcpy(struct dma_chan *c, dma_addr_t dma_dest,
467 dma_addr_t dma_src, size_t len, unsigned long flags)
469 struct ioat_dma_chan *ioat = to_ioat_chan(c);
470 struct ioat_desc_sw *desc;
473 dma_addr_t src = dma_src;
474 dma_addr_t dest = dma_dest;
475 size_t total_len = len;
476 struct ioat_dma_descriptor *hw = NULL;
479 spin_lock_bh(&ioat->desc_lock);
480 desc = ioat1_dma_get_next_descriptor(ioat);
486 copy = min_t(size_t, len, ioat->xfercap);
494 list_add_tail(&desc->node, &chain);
500 struct ioat_desc_sw *next;
502 async_tx_ack(&desc->txd);
503 next = ioat1_dma_get_next_descriptor(ioat);
504 hw->next = next ? next->txd.phys : 0;
505 dump_desc_dbg(ioat, desc);
512 struct ioat_chan_common *chan = &ioat->base;
514 dev_err(to_dev(chan),
515 "chan%d - get_next_desc failed\n", chan_num(chan));
516 list_splice(&chain, &ioat->free_desc);
517 spin_unlock_bh(&ioat->desc_lock);
520 spin_unlock_bh(&ioat->desc_lock);
522 desc->txd.flags = flags;
523 desc->len = total_len;
524 list_splice(&chain, &desc->txd.tx_list);
525 hw->ctl_f.int_en = !!(flags & DMA_PREP_INTERRUPT);
526 hw->ctl_f.compl_write = 1;
528 dump_desc_dbg(ioat, desc);
533 static void ioat1_cleanup_tasklet(unsigned long data)
535 struct ioat_dma_chan *chan = (void *)data;
538 writew(IOAT_CHANCTRL_RUN, chan->base.reg_base + IOAT_CHANCTRL_OFFSET);
541 static void ioat_unmap(struct pci_dev *pdev, dma_addr_t addr, size_t len,
542 int direction, enum dma_ctrl_flags flags, bool dst)
544 if ((dst && (flags & DMA_COMPL_DEST_UNMAP_SINGLE)) ||
545 (!dst && (flags & DMA_COMPL_SRC_UNMAP_SINGLE)))
546 pci_unmap_single(pdev, addr, len, direction);
548 pci_unmap_page(pdev, addr, len, direction);
552 void ioat_dma_unmap(struct ioat_chan_common *chan, enum dma_ctrl_flags flags,
553 size_t len, struct ioat_dma_descriptor *hw)
555 struct pci_dev *pdev = chan->device->pdev;
556 size_t offset = len - hw->size;
558 if (!(flags & DMA_COMPL_SKIP_DEST_UNMAP))
559 ioat_unmap(pdev, hw->dst_addr - offset, len,
560 PCI_DMA_FROMDEVICE, flags, 1);
562 if (!(flags & DMA_COMPL_SKIP_SRC_UNMAP))
563 ioat_unmap(pdev, hw->src_addr - offset, len,
564 PCI_DMA_TODEVICE, flags, 0);
567 unsigned long ioat_get_current_completion(struct ioat_chan_common *chan)
569 unsigned long phys_complete;
572 completion = *chan->completion;
573 phys_complete = ioat_chansts_to_addr(completion);
575 dev_dbg(to_dev(chan), "%s: phys_complete: %#llx\n", __func__,
576 (unsigned long long) phys_complete);
578 if (is_ioat_halted(completion)) {
579 u32 chanerr = readl(chan->reg_base + IOAT_CHANERR_OFFSET);
580 dev_err(to_dev(chan), "Channel halted, chanerr = %x\n",
583 /* TODO do something to salvage the situation */
586 return phys_complete;
589 bool ioat_cleanup_preamble(struct ioat_chan_common *chan,
590 unsigned long *phys_complete)
592 *phys_complete = ioat_get_current_completion(chan);
593 if (*phys_complete == chan->last_completion)
595 clear_bit(IOAT_COMPLETION_ACK, &chan->state);
596 mod_timer(&chan->timer, jiffies + COMPLETION_TIMEOUT);
601 static void __cleanup(struct ioat_dma_chan *ioat, unsigned long phys_complete)
603 struct ioat_chan_common *chan = &ioat->base;
604 struct list_head *_desc, *n;
605 struct dma_async_tx_descriptor *tx;
607 dev_dbg(to_dev(chan), "%s: phys_complete: %lx\n",
608 __func__, phys_complete);
609 list_for_each_safe(_desc, n, &ioat->used_desc) {
610 struct ioat_desc_sw *desc;
613 desc = list_entry(_desc, typeof(*desc), node);
616 * Incoming DMA requests may use multiple descriptors,
617 * due to exceeding xfercap, perhaps. If so, only the
618 * last one will have a cookie, and require unmapping.
620 dump_desc_dbg(ioat, desc);
622 chan->completed_cookie = tx->cookie;
624 ioat_dma_unmap(chan, tx->flags, desc->len, desc->hw);
626 tx->callback(tx->callback_param);
631 if (tx->phys != phys_complete) {
633 * a completed entry, but not the last, so clean
634 * up if the client is done with the descriptor
636 if (async_tx_test_ack(tx))
637 list_move_tail(&desc->node, &ioat->free_desc);
640 * last used desc. Do not remove, so we can
644 /* if nothing else is pending, cancel the
647 if (n == &ioat->used_desc) {
648 dev_dbg(to_dev(chan),
649 "%s cancel completion timeout\n",
651 clear_bit(IOAT_COMPLETION_PENDING, &chan->state);
654 /* TODO check status bits? */
659 chan->last_completion = phys_complete;
663 * ioat1_cleanup - cleanup up finished descriptors
664 * @chan: ioat channel to be cleaned up
666 * To prevent lock contention we defer cleanup when the locks are
667 * contended with a terminal timeout that forces cleanup and catches
668 * completion notification errors.
670 static void ioat1_cleanup(struct ioat_dma_chan *ioat)
672 struct ioat_chan_common *chan = &ioat->base;
673 unsigned long phys_complete;
675 prefetch(chan->completion);
677 if (!spin_trylock_bh(&chan->cleanup_lock))
680 if (!ioat_cleanup_preamble(chan, &phys_complete)) {
681 spin_unlock_bh(&chan->cleanup_lock);
685 if (!spin_trylock_bh(&ioat->desc_lock)) {
686 spin_unlock_bh(&chan->cleanup_lock);
690 __cleanup(ioat, phys_complete);
692 spin_unlock_bh(&ioat->desc_lock);
693 spin_unlock_bh(&chan->cleanup_lock);
696 static void ioat1_timer_event(unsigned long data)
698 struct ioat_dma_chan *ioat = (void *) data;
699 struct ioat_chan_common *chan = &ioat->base;
701 dev_dbg(to_dev(chan), "%s: state: %lx\n", __func__, chan->state);
703 spin_lock_bh(&chan->cleanup_lock);
704 if (test_and_clear_bit(IOAT_RESET_PENDING, &chan->state)) {
705 struct ioat_desc_sw *desc;
707 spin_lock_bh(&ioat->desc_lock);
709 /* restart active descriptors */
710 desc = to_ioat_desc(ioat->used_desc.prev);
711 ioat_set_chainaddr(ioat, desc->txd.phys);
715 set_bit(IOAT_COMPLETION_PENDING, &chan->state);
716 mod_timer(&chan->timer, jiffies + COMPLETION_TIMEOUT);
717 spin_unlock_bh(&ioat->desc_lock);
718 } else if (test_bit(IOAT_COMPLETION_PENDING, &chan->state)) {
719 unsigned long phys_complete;
721 spin_lock_bh(&ioat->desc_lock);
722 /* if we haven't made progress and we have already
723 * acknowledged a pending completion once, then be more
724 * forceful with a restart
726 if (ioat_cleanup_preamble(chan, &phys_complete))
727 __cleanup(ioat, phys_complete);
728 else if (test_bit(IOAT_COMPLETION_ACK, &chan->state))
729 ioat1_reset_channel(ioat);
731 u64 status = ioat_chansts(chan);
733 /* manually update the last completion address */
734 if (ioat_chansts_to_addr(status) != 0)
735 *chan->completion = status;
737 set_bit(IOAT_COMPLETION_ACK, &chan->state);
738 mod_timer(&chan->timer, jiffies + COMPLETION_TIMEOUT);
740 spin_unlock_bh(&ioat->desc_lock);
742 spin_unlock_bh(&chan->cleanup_lock);
745 static enum dma_status
746 ioat1_dma_is_complete(struct dma_chan *c, dma_cookie_t cookie,
747 dma_cookie_t *done, dma_cookie_t *used)
749 struct ioat_dma_chan *ioat = to_ioat_chan(c);
751 if (ioat_is_complete(c, cookie, done, used) == DMA_SUCCESS)
756 return ioat_is_complete(c, cookie, done, used);
759 static void ioat1_dma_start_null_desc(struct ioat_dma_chan *ioat)
761 struct ioat_chan_common *chan = &ioat->base;
762 struct ioat_desc_sw *desc;
763 struct ioat_dma_descriptor *hw;
765 spin_lock_bh(&ioat->desc_lock);
767 desc = ioat1_dma_get_next_descriptor(ioat);
770 dev_err(to_dev(chan),
771 "Unable to start null desc - get next desc failed\n");
772 spin_unlock_bh(&ioat->desc_lock);
779 hw->ctl_f.int_en = 1;
780 hw->ctl_f.compl_write = 1;
781 /* set size to non-zero value (channel returns error when size is 0) */
782 hw->size = NULL_DESC_BUFFER_SIZE;
785 async_tx_ack(&desc->txd);
787 list_add_tail(&desc->node, &ioat->used_desc);
788 dump_desc_dbg(ioat, desc);
790 ioat_set_chainaddr(ioat, desc->txd.phys);
792 spin_unlock_bh(&ioat->desc_lock);
796 * Perform a IOAT transaction to verify the HW works.
798 #define IOAT_TEST_SIZE 2000
800 static void __devinit ioat_dma_test_callback(void *dma_async_param)
802 struct completion *cmp = dma_async_param;
808 * ioat_dma_self_test - Perform a IOAT transaction to verify the HW works.
809 * @device: device to be tested
811 static int __devinit ioat_dma_self_test(struct ioatdma_device *device)
816 struct dma_device *dma = &device->common;
817 struct device *dev = &device->pdev->dev;
818 struct dma_chan *dma_chan;
819 struct dma_async_tx_descriptor *tx;
820 dma_addr_t dma_dest, dma_src;
823 struct completion cmp;
827 src = kzalloc(sizeof(u8) * IOAT_TEST_SIZE, GFP_KERNEL);
830 dest = kzalloc(sizeof(u8) * IOAT_TEST_SIZE, GFP_KERNEL);
836 /* Fill in src buffer */
837 for (i = 0; i < IOAT_TEST_SIZE; i++)
840 /* Start copy, using first DMA channel */
841 dma_chan = container_of(dma->channels.next, struct dma_chan,
843 if (dma->device_alloc_chan_resources(dma_chan) < 1) {
844 dev_err(dev, "selftest cannot allocate chan resource\n");
849 dma_src = dma_map_single(dev, src, IOAT_TEST_SIZE, DMA_TO_DEVICE);
850 dma_dest = dma_map_single(dev, dest, IOAT_TEST_SIZE, DMA_FROM_DEVICE);
851 flags = DMA_COMPL_SRC_UNMAP_SINGLE | DMA_COMPL_DEST_UNMAP_SINGLE |
853 tx = device->common.device_prep_dma_memcpy(dma_chan, dma_dest, dma_src,
854 IOAT_TEST_SIZE, flags);
856 dev_err(dev, "Self-test prep failed, disabling\n");
862 init_completion(&cmp);
863 tx->callback = ioat_dma_test_callback;
864 tx->callback_param = &cmp;
865 cookie = tx->tx_submit(tx);
867 dev_err(dev, "Self-test setup failed, disabling\n");
871 dma->device_issue_pending(dma_chan);
873 tmo = wait_for_completion_timeout(&cmp, msecs_to_jiffies(3000));
876 dma->device_is_tx_complete(dma_chan, cookie, NULL, NULL)
878 dev_err(dev, "Self-test copy timed out, disabling\n");
882 if (memcmp(src, dest, IOAT_TEST_SIZE)) {
883 dev_err(dev, "Self-test copy failed compare, disabling\n");
889 dma->device_free_chan_resources(dma_chan);
896 static char ioat_interrupt_style[32] = "msix";
897 module_param_string(ioat_interrupt_style, ioat_interrupt_style,
898 sizeof(ioat_interrupt_style), 0644);
899 MODULE_PARM_DESC(ioat_interrupt_style,
900 "set ioat interrupt style: msix (default), "
901 "msix-single-vector, msi, intx)");
904 * ioat_dma_setup_interrupts - setup interrupt handler
905 * @device: ioat device
907 static int ioat_dma_setup_interrupts(struct ioatdma_device *device)
909 struct ioat_chan_common *chan;
910 struct pci_dev *pdev = device->pdev;
911 struct device *dev = &pdev->dev;
912 struct msix_entry *msix;
917 if (!strcmp(ioat_interrupt_style, "msix"))
919 if (!strcmp(ioat_interrupt_style, "msix-single-vector"))
920 goto msix_single_vector;
921 if (!strcmp(ioat_interrupt_style, "msi"))
923 if (!strcmp(ioat_interrupt_style, "intx"))
925 dev_err(dev, "invalid ioat_interrupt_style %s\n", ioat_interrupt_style);
929 /* The number of MSI-X vectors should equal the number of channels */
930 msixcnt = device->common.chancnt;
931 for (i = 0; i < msixcnt; i++)
932 device->msix_entries[i].entry = i;
934 err = pci_enable_msix(pdev, device->msix_entries, msixcnt);
938 goto msix_single_vector;
940 for (i = 0; i < msixcnt; i++) {
941 msix = &device->msix_entries[i];
942 chan = ioat_chan_by_index(device, i);
943 err = devm_request_irq(dev, msix->vector,
944 ioat_dma_do_interrupt_msix, 0,
947 for (j = 0; j < i; j++) {
948 msix = &device->msix_entries[j];
949 chan = ioat_chan_by_index(device, j);
950 devm_free_irq(dev, msix->vector, chan);
952 goto msix_single_vector;
955 intrctrl |= IOAT_INTRCTRL_MSIX_VECTOR_CONTROL;
959 msix = &device->msix_entries[0];
961 err = pci_enable_msix(pdev, device->msix_entries, 1);
965 err = devm_request_irq(dev, msix->vector, ioat_dma_do_interrupt, 0,
966 "ioat-msix", device);
968 pci_disable_msix(pdev);
974 err = pci_enable_msi(pdev);
978 err = devm_request_irq(dev, pdev->irq, ioat_dma_do_interrupt, 0,
981 pci_disable_msi(pdev);
987 err = devm_request_irq(dev, pdev->irq, ioat_dma_do_interrupt,
988 IRQF_SHARED, "ioat-intx", device);
993 if (device->intr_quirk)
994 device->intr_quirk(device);
995 intrctrl |= IOAT_INTRCTRL_MASTER_INT_EN;
996 writeb(intrctrl, device->reg_base + IOAT_INTRCTRL_OFFSET);
1000 /* Disable all interrupt generation */
1001 writeb(0, device->reg_base + IOAT_INTRCTRL_OFFSET);
1002 dev_err(dev, "no usable interrupts\n");
1006 static void ioat_disable_interrupts(struct ioatdma_device *device)
1008 /* Disable all interrupt generation */
1009 writeb(0, device->reg_base + IOAT_INTRCTRL_OFFSET);
1012 int __devinit ioat_probe(struct ioatdma_device *device)
1015 struct dma_device *dma = &device->common;
1016 struct pci_dev *pdev = device->pdev;
1017 struct device *dev = &pdev->dev;
1019 /* DMA coherent memory pool for DMA descriptor allocations */
1020 device->dma_pool = pci_pool_create("dma_desc_pool", pdev,
1021 sizeof(struct ioat_dma_descriptor),
1023 if (!device->dma_pool) {
1028 device->completion_pool = pci_pool_create("completion_pool", pdev,
1029 sizeof(u64), SMP_CACHE_BYTES,
1032 if (!device->completion_pool) {
1034 goto err_completion_pool;
1037 device->enumerate_channels(device);
1039 dma_cap_set(DMA_MEMCPY, dma->cap_mask);
1040 dma->dev = &pdev->dev;
1042 dev_err(dev, "Intel(R) I/OAT DMA Engine found,"
1043 " %d channels, device version 0x%02x, driver version %s\n",
1044 dma->chancnt, device->version, IOAT_DMA_VERSION);
1046 if (!dma->chancnt) {
1047 dev_err(dev, "Intel(R) I/OAT DMA Engine problem found: "
1048 "zero channels detected\n");
1049 goto err_setup_interrupts;
1052 err = ioat_dma_setup_interrupts(device);
1054 goto err_setup_interrupts;
1056 err = ioat_dma_self_test(device);
1063 ioat_disable_interrupts(device);
1064 err_setup_interrupts:
1065 pci_pool_destroy(device->completion_pool);
1066 err_completion_pool:
1067 pci_pool_destroy(device->dma_pool);
1072 int __devinit ioat_register(struct ioatdma_device *device)
1074 int err = dma_async_device_register(&device->common);
1077 ioat_disable_interrupts(device);
1078 pci_pool_destroy(device->completion_pool);
1079 pci_pool_destroy(device->dma_pool);
1085 /* ioat1_intr_quirk - fix up dma ctrl register to enable / disable msi */
1086 static void ioat1_intr_quirk(struct ioatdma_device *device)
1088 struct pci_dev *pdev = device->pdev;
1091 pci_read_config_dword(pdev, IOAT_PCI_DMACTRL_OFFSET, &dmactrl);
1092 if (pdev->msi_enabled)
1093 dmactrl |= IOAT_PCI_DMACTRL_MSI_EN;
1095 dmactrl &= ~IOAT_PCI_DMACTRL_MSI_EN;
1096 pci_write_config_dword(pdev, IOAT_PCI_DMACTRL_OFFSET, dmactrl);
1099 int __devinit ioat1_dma_probe(struct ioatdma_device *device, int dca)
1101 struct pci_dev *pdev = device->pdev;
1102 struct dma_device *dma;
1105 device->intr_quirk = ioat1_intr_quirk;
1106 device->enumerate_channels = ioat1_enumerate_channels;
1107 dma = &device->common;
1108 dma->device_prep_dma_memcpy = ioat1_dma_prep_memcpy;
1109 dma->device_issue_pending = ioat1_dma_memcpy_issue_pending;
1110 dma->device_alloc_chan_resources = ioat1_dma_alloc_chan_resources;
1111 dma->device_free_chan_resources = ioat1_dma_free_chan_resources;
1112 dma->device_is_tx_complete = ioat1_dma_is_complete;
1114 err = ioat_probe(device);
1117 ioat_set_tcp_copy_break(4096);
1118 err = ioat_register(device);
1122 device->dca = ioat_dca_init(pdev, device->reg_base);
1127 void __devexit ioat_dma_remove(struct ioatdma_device *device)
1129 struct dma_device *dma = &device->common;
1131 ioat_disable_interrupts(device);
1133 dma_async_device_unregister(dma);
1135 pci_pool_destroy(device->dma_pool);
1136 pci_pool_destroy(device->completion_pool);
1138 INIT_LIST_HEAD(&dma->channels);