2 * Intel I/OAT DMA Linux driver
3 * Copyright(c) 2004 - 2007 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>
36 #include "ioatdma_registers.h"
37 #include "ioatdma_hw.h"
39 #define to_ioat_chan(chan) container_of(chan, struct ioat_dma_chan, common)
40 #define to_ioatdma_device(dev) container_of(dev, struct ioatdma_device, common)
41 #define to_ioat_desc(lh) container_of(lh, struct ioat_desc_sw, node)
42 #define tx_to_ioat_desc(tx) container_of(tx, struct ioat_desc_sw, async_tx)
44 static int ioat_pending_level = 4;
45 module_param(ioat_pending_level, int, 0644);
46 MODULE_PARM_DESC(ioat_pending_level,
47 "high-water mark for pushing ioat descriptors (default: 4)");
49 /* internal functions */
50 static void ioat_dma_start_null_desc(struct ioat_dma_chan *ioat_chan);
51 static void ioat_dma_memcpy_cleanup(struct ioat_dma_chan *ioat_chan);
53 static struct ioat_desc_sw *
54 ioat1_dma_get_next_descriptor(struct ioat_dma_chan *ioat_chan);
55 static struct ioat_desc_sw *
56 ioat2_dma_get_next_descriptor(struct ioat_dma_chan *ioat_chan);
58 static inline struct ioat_dma_chan *ioat_lookup_chan_by_index(
59 struct ioatdma_device *device,
62 return device->idx[index];
66 * ioat_dma_do_interrupt - handler used for single vector interrupt mode
68 * @data: interrupt data
70 static irqreturn_t ioat_dma_do_interrupt(int irq, void *data)
72 struct ioatdma_device *instance = data;
73 struct ioat_dma_chan *ioat_chan;
74 unsigned long attnstatus;
78 intrctrl = readb(instance->reg_base + IOAT_INTRCTRL_OFFSET);
80 if (!(intrctrl & IOAT_INTRCTRL_MASTER_INT_EN))
83 if (!(intrctrl & IOAT_INTRCTRL_INT_STATUS)) {
84 writeb(intrctrl, instance->reg_base + IOAT_INTRCTRL_OFFSET);
88 attnstatus = readl(instance->reg_base + IOAT_ATTNSTATUS_OFFSET);
89 for_each_bit(bit, &attnstatus, BITS_PER_LONG) {
90 ioat_chan = ioat_lookup_chan_by_index(instance, bit);
91 tasklet_schedule(&ioat_chan->cleanup_task);
94 writeb(intrctrl, instance->reg_base + IOAT_INTRCTRL_OFFSET);
99 * ioat_dma_do_interrupt_msix - handler used for vector-per-channel interrupt mode
101 * @data: interrupt data
103 static irqreturn_t ioat_dma_do_interrupt_msix(int irq, void *data)
105 struct ioat_dma_chan *ioat_chan = data;
107 tasklet_schedule(&ioat_chan->cleanup_task);
112 static void ioat_dma_cleanup_tasklet(unsigned long data);
115 * ioat_dma_enumerate_channels - find and initialize the device's channels
116 * @device: the device to be enumerated
118 static int ioat_dma_enumerate_channels(struct ioatdma_device *device)
123 struct ioat_dma_chan *ioat_chan;
125 device->common.chancnt = readb(device->reg_base + IOAT_CHANCNT_OFFSET);
126 xfercap_scale = readb(device->reg_base + IOAT_XFERCAP_OFFSET);
127 xfercap = (xfercap_scale == 0 ? -1 : (1UL << xfercap_scale));
129 for (i = 0; i < device->common.chancnt; i++) {
130 ioat_chan = kzalloc(sizeof(*ioat_chan), GFP_KERNEL);
132 device->common.chancnt = i;
136 ioat_chan->device = device;
137 ioat_chan->reg_base = device->reg_base + (0x80 * (i + 1));
138 ioat_chan->xfercap = xfercap;
139 ioat_chan->desccount = 0;
140 if (ioat_chan->device->version != IOAT_VER_1_2) {
141 writel(IOAT_DCACTRL_CMPL_WRITE_ENABLE
142 | IOAT_DMA_DCA_ANY_CPU,
143 ioat_chan->reg_base + IOAT_DCACTRL_OFFSET);
145 spin_lock_init(&ioat_chan->cleanup_lock);
146 spin_lock_init(&ioat_chan->desc_lock);
147 INIT_LIST_HEAD(&ioat_chan->free_desc);
148 INIT_LIST_HEAD(&ioat_chan->used_desc);
149 /* This should be made common somewhere in dmaengine.c */
150 ioat_chan->common.device = &device->common;
151 list_add_tail(&ioat_chan->common.device_node,
152 &device->common.channels);
153 device->idx[i] = ioat_chan;
154 tasklet_init(&ioat_chan->cleanup_task,
155 ioat_dma_cleanup_tasklet,
156 (unsigned long) ioat_chan);
157 tasklet_disable(&ioat_chan->cleanup_task);
159 return device->common.chancnt;
163 * ioat_dma_memcpy_issue_pending - push potentially unrecognized appended
165 * @chan: DMA channel handle
167 static inline void __ioat1_dma_memcpy_issue_pending(
168 struct ioat_dma_chan *ioat_chan)
170 ioat_chan->pending = 0;
171 writeb(IOAT_CHANCMD_APPEND, ioat_chan->reg_base + IOAT1_CHANCMD_OFFSET);
174 static void ioat1_dma_memcpy_issue_pending(struct dma_chan *chan)
176 struct ioat_dma_chan *ioat_chan = to_ioat_chan(chan);
178 if (ioat_chan->pending != 0) {
179 spin_lock_bh(&ioat_chan->desc_lock);
180 __ioat1_dma_memcpy_issue_pending(ioat_chan);
181 spin_unlock_bh(&ioat_chan->desc_lock);
185 static inline void __ioat2_dma_memcpy_issue_pending(
186 struct ioat_dma_chan *ioat_chan)
188 ioat_chan->pending = 0;
189 writew(ioat_chan->dmacount,
190 ioat_chan->reg_base + IOAT_CHAN_DMACOUNT_OFFSET);
193 static void ioat2_dma_memcpy_issue_pending(struct dma_chan *chan)
195 struct ioat_dma_chan *ioat_chan = to_ioat_chan(chan);
197 if (ioat_chan->pending != 0) {
198 spin_lock_bh(&ioat_chan->desc_lock);
199 __ioat2_dma_memcpy_issue_pending(ioat_chan);
200 spin_unlock_bh(&ioat_chan->desc_lock);
204 static dma_cookie_t ioat1_tx_submit(struct dma_async_tx_descriptor *tx)
206 struct ioat_dma_chan *ioat_chan = to_ioat_chan(tx->chan);
207 struct ioat_desc_sw *first = tx_to_ioat_desc(tx);
208 struct ioat_desc_sw *prev, *new;
209 struct ioat_dma_descriptor *hw;
211 LIST_HEAD(new_chain);
216 unsigned int desc_count = 0;
218 /* src and dest and len are stored in the initial descriptor */
222 orig_ack = first->async_tx.ack;
225 spin_lock_bh(&ioat_chan->desc_lock);
226 prev = to_ioat_desc(ioat_chan->used_desc.prev);
229 copy = min_t(size_t, len, ioat_chan->xfercap);
231 new->async_tx.ack = 1;
240 /* chain together the physical address list for the HW */
242 prev->hw->next = (u64) new->async_tx.phys;
248 list_add_tail(&new->node, &new_chain);
251 } while (len && (new = ioat1_dma_get_next_descriptor(ioat_chan)));
253 hw->ctl = IOAT_DMA_DESCRIPTOR_CTL_CP_STS;
254 if (new->async_tx.callback) {
255 hw->ctl |= IOAT_DMA_DESCRIPTOR_CTL_INT_GN;
257 /* move callback into to last desc */
258 new->async_tx.callback = first->async_tx.callback;
259 new->async_tx.callback_param
260 = first->async_tx.callback_param;
261 first->async_tx.callback = NULL;
262 first->async_tx.callback_param = NULL;
266 new->tx_cnt = desc_count;
267 new->async_tx.ack = orig_ack; /* client is in control of this ack */
269 /* store the original values for use in later cleanup */
271 new->src = first->src;
272 new->dst = first->dst;
273 new->len = first->len;
276 /* cookie incr and addition to used_list must be atomic */
277 cookie = ioat_chan->common.cookie;
281 ioat_chan->common.cookie = new->async_tx.cookie = cookie;
283 /* write address into NextDescriptor field of last desc in chain */
284 to_ioat_desc(ioat_chan->used_desc.prev)->hw->next =
285 first->async_tx.phys;
286 __list_splice(&new_chain, ioat_chan->used_desc.prev);
288 ioat_chan->dmacount += desc_count;
289 ioat_chan->pending += desc_count;
290 if (ioat_chan->pending >= ioat_pending_level)
291 __ioat1_dma_memcpy_issue_pending(ioat_chan);
292 spin_unlock_bh(&ioat_chan->desc_lock);
297 static dma_cookie_t ioat2_tx_submit(struct dma_async_tx_descriptor *tx)
299 struct ioat_dma_chan *ioat_chan = to_ioat_chan(tx->chan);
300 struct ioat_desc_sw *first = tx_to_ioat_desc(tx);
301 struct ioat_desc_sw *new;
302 struct ioat_dma_descriptor *hw;
308 unsigned int desc_count = 0;
310 /* src and dest and len are stored in the initial descriptor */
314 orig_ack = first->async_tx.ack;
318 * ioat_chan->desc_lock is still in force in version 2 path
319 * it gets unlocked at end of this function
322 copy = min_t(size_t, len, ioat_chan->xfercap);
324 new->async_tx.ack = 1;
336 } while (len && (new = ioat2_dma_get_next_descriptor(ioat_chan)));
338 hw->ctl = IOAT_DMA_DESCRIPTOR_CTL_CP_STS;
339 if (new->async_tx.callback) {
340 hw->ctl |= IOAT_DMA_DESCRIPTOR_CTL_INT_GN;
342 /* move callback into to last desc */
343 new->async_tx.callback = first->async_tx.callback;
344 new->async_tx.callback_param
345 = first->async_tx.callback_param;
346 first->async_tx.callback = NULL;
347 first->async_tx.callback_param = NULL;
351 new->tx_cnt = desc_count;
352 new->async_tx.ack = orig_ack; /* client is in control of this ack */
354 /* store the original values for use in later cleanup */
356 new->src = first->src;
357 new->dst = first->dst;
358 new->len = first->len;
361 /* cookie incr and addition to used_list must be atomic */
362 cookie = ioat_chan->common.cookie;
366 ioat_chan->common.cookie = new->async_tx.cookie = cookie;
368 ioat_chan->dmacount += desc_count;
369 ioat_chan->pending += desc_count;
370 if (ioat_chan->pending >= ioat_pending_level)
371 __ioat2_dma_memcpy_issue_pending(ioat_chan);
372 spin_unlock_bh(&ioat_chan->desc_lock);
378 * ioat_dma_alloc_descriptor - allocate and return a sw and hw descriptor pair
379 * @ioat_chan: the channel supplying the memory pool for the descriptors
380 * @flags: allocation flags
382 static struct ioat_desc_sw *ioat_dma_alloc_descriptor(
383 struct ioat_dma_chan *ioat_chan,
386 struct ioat_dma_descriptor *desc;
387 struct ioat_desc_sw *desc_sw;
388 struct ioatdma_device *ioatdma_device;
391 ioatdma_device = to_ioatdma_device(ioat_chan->common.device);
392 desc = pci_pool_alloc(ioatdma_device->dma_pool, flags, &phys);
396 desc_sw = kzalloc(sizeof(*desc_sw), flags);
397 if (unlikely(!desc_sw)) {
398 pci_pool_free(ioatdma_device->dma_pool, desc, phys);
402 memset(desc, 0, sizeof(*desc));
403 dma_async_tx_descriptor_init(&desc_sw->async_tx, &ioat_chan->common);
404 switch (ioat_chan->device->version) {
406 desc_sw->async_tx.tx_submit = ioat1_tx_submit;
409 desc_sw->async_tx.tx_submit = ioat2_tx_submit;
412 INIT_LIST_HEAD(&desc_sw->async_tx.tx_list);
415 desc_sw->async_tx.phys = phys;
420 static int ioat_initial_desc_count = 256;
421 module_param(ioat_initial_desc_count, int, 0644);
422 MODULE_PARM_DESC(ioat_initial_desc_count,
423 "initial descriptors per channel (default: 256)");
426 * ioat2_dma_massage_chan_desc - link the descriptors into a circle
427 * @ioat_chan: the channel to be massaged
429 static void ioat2_dma_massage_chan_desc(struct ioat_dma_chan *ioat_chan)
431 struct ioat_desc_sw *desc, *_desc;
433 /* setup used_desc */
434 ioat_chan->used_desc.next = ioat_chan->free_desc.next;
435 ioat_chan->used_desc.prev = NULL;
437 /* pull free_desc out of the circle so that every node is a hw
438 * descriptor, but leave it pointing to the list
440 ioat_chan->free_desc.prev->next = ioat_chan->free_desc.next;
441 ioat_chan->free_desc.next->prev = ioat_chan->free_desc.prev;
443 /* circle link the hw descriptors */
444 desc = to_ioat_desc(ioat_chan->free_desc.next);
445 desc->hw->next = to_ioat_desc(desc->node.next)->async_tx.phys;
446 list_for_each_entry_safe(desc, _desc, ioat_chan->free_desc.next, node) {
447 desc->hw->next = to_ioat_desc(desc->node.next)->async_tx.phys;
452 * ioat_dma_alloc_chan_resources - returns the number of allocated descriptors
453 * @chan: the channel to be filled out
455 static int ioat_dma_alloc_chan_resources(struct dma_chan *chan)
457 struct ioat_dma_chan *ioat_chan = to_ioat_chan(chan);
458 struct ioat_desc_sw *desc;
464 /* have we already been set up? */
465 if (!list_empty(&ioat_chan->free_desc))
466 return ioat_chan->desccount;
468 /* Setup register to interrupt and write completion status on error */
469 chanctrl = IOAT_CHANCTRL_ERR_INT_EN |
470 IOAT_CHANCTRL_ANY_ERR_ABORT_EN |
471 IOAT_CHANCTRL_ERR_COMPLETION_EN;
472 writew(chanctrl, ioat_chan->reg_base + IOAT_CHANCTRL_OFFSET);
474 chanerr = readl(ioat_chan->reg_base + IOAT_CHANERR_OFFSET);
476 dev_err(&ioat_chan->device->pdev->dev,
477 "CHANERR = %x, clearing\n", chanerr);
478 writel(chanerr, ioat_chan->reg_base + IOAT_CHANERR_OFFSET);
481 /* Allocate descriptors */
482 for (i = 0; i < ioat_initial_desc_count; i++) {
483 desc = ioat_dma_alloc_descriptor(ioat_chan, GFP_KERNEL);
485 dev_err(&ioat_chan->device->pdev->dev,
486 "Only %d initial descriptors\n", i);
489 list_add_tail(&desc->node, &tmp_list);
491 spin_lock_bh(&ioat_chan->desc_lock);
492 ioat_chan->desccount = i;
493 list_splice(&tmp_list, &ioat_chan->free_desc);
494 if (ioat_chan->device->version != IOAT_VER_1_2)
495 ioat2_dma_massage_chan_desc(ioat_chan);
496 spin_unlock_bh(&ioat_chan->desc_lock);
498 /* allocate a completion writeback area */
499 /* doing 2 32bit writes to mmio since 1 64b write doesn't work */
500 ioat_chan->completion_virt =
501 pci_pool_alloc(ioat_chan->device->completion_pool,
503 &ioat_chan->completion_addr);
504 memset(ioat_chan->completion_virt, 0,
505 sizeof(*ioat_chan->completion_virt));
506 writel(((u64) ioat_chan->completion_addr) & 0x00000000FFFFFFFF,
507 ioat_chan->reg_base + IOAT_CHANCMP_OFFSET_LOW);
508 writel(((u64) ioat_chan->completion_addr) >> 32,
509 ioat_chan->reg_base + IOAT_CHANCMP_OFFSET_HIGH);
511 tasklet_enable(&ioat_chan->cleanup_task);
512 ioat_dma_start_null_desc(ioat_chan); /* give chain to dma device */
513 return ioat_chan->desccount;
517 * ioat_dma_free_chan_resources - release all the descriptors
518 * @chan: the channel to be cleaned
520 static void ioat_dma_free_chan_resources(struct dma_chan *chan)
522 struct ioat_dma_chan *ioat_chan = to_ioat_chan(chan);
523 struct ioatdma_device *ioatdma_device = to_ioatdma_device(chan->device);
524 struct ioat_desc_sw *desc, *_desc;
525 int in_use_descs = 0;
527 tasklet_disable(&ioat_chan->cleanup_task);
528 ioat_dma_memcpy_cleanup(ioat_chan);
530 /* Delay 100ms after reset to allow internal DMA logic to quiesce
531 * before removing DMA descriptor resources.
533 writeb(IOAT_CHANCMD_RESET,
535 + IOAT_CHANCMD_OFFSET(ioat_chan->device->version));
538 spin_lock_bh(&ioat_chan->desc_lock);
539 switch (ioat_chan->device->version) {
541 list_for_each_entry_safe(desc, _desc,
542 &ioat_chan->used_desc, node) {
544 list_del(&desc->node);
545 pci_pool_free(ioatdma_device->dma_pool, desc->hw,
546 desc->async_tx.phys);
549 list_for_each_entry_safe(desc, _desc,
550 &ioat_chan->free_desc, node) {
551 list_del(&desc->node);
552 pci_pool_free(ioatdma_device->dma_pool, desc->hw,
553 desc->async_tx.phys);
558 list_for_each_entry_safe(desc, _desc,
559 ioat_chan->free_desc.next, node) {
560 list_del(&desc->node);
561 pci_pool_free(ioatdma_device->dma_pool, desc->hw,
562 desc->async_tx.phys);
565 desc = to_ioat_desc(ioat_chan->free_desc.next);
566 pci_pool_free(ioatdma_device->dma_pool, desc->hw,
567 desc->async_tx.phys);
569 INIT_LIST_HEAD(&ioat_chan->free_desc);
570 INIT_LIST_HEAD(&ioat_chan->used_desc);
573 spin_unlock_bh(&ioat_chan->desc_lock);
575 pci_pool_free(ioatdma_device->completion_pool,
576 ioat_chan->completion_virt,
577 ioat_chan->completion_addr);
579 /* one is ok since we left it on there on purpose */
580 if (in_use_descs > 1)
581 dev_err(&ioat_chan->device->pdev->dev,
582 "Freeing %d in use descriptors!\n",
585 ioat_chan->last_completion = ioat_chan->completion_addr = 0;
586 ioat_chan->pending = 0;
587 ioat_chan->dmacount = 0;
591 * ioat_dma_get_next_descriptor - return the next available descriptor
592 * @ioat_chan: IOAT DMA channel handle
594 * Gets the next descriptor from the chain, and must be called with the
595 * channel's desc_lock held. Allocates more descriptors if the channel
598 static struct ioat_desc_sw *
599 ioat1_dma_get_next_descriptor(struct ioat_dma_chan *ioat_chan)
601 struct ioat_desc_sw *new;
603 if (!list_empty(&ioat_chan->free_desc)) {
604 new = to_ioat_desc(ioat_chan->free_desc.next);
605 list_del(&new->node);
607 /* try to get another desc */
608 new = ioat_dma_alloc_descriptor(ioat_chan, GFP_ATOMIC);
610 dev_err(&ioat_chan->device->pdev->dev,
620 static struct ioat_desc_sw *
621 ioat2_dma_get_next_descriptor(struct ioat_dma_chan *ioat_chan)
623 struct ioat_desc_sw *new;
626 * used.prev points to where to start processing
627 * used.next points to next free descriptor
628 * if used.prev == NULL, there are none waiting to be processed
629 * if used.next == used.prev.prev, there is only one free descriptor,
630 * and we need to use it to as a noop descriptor before
631 * linking in a new set of descriptors, since the device
632 * has probably already read the pointer to it
634 if (ioat_chan->used_desc.prev &&
635 ioat_chan->used_desc.next == ioat_chan->used_desc.prev->prev) {
637 struct ioat_desc_sw *desc;
638 struct ioat_desc_sw *noop_desc;
641 /* set up the noop descriptor */
642 noop_desc = to_ioat_desc(ioat_chan->used_desc.next);
643 noop_desc->hw->size = 0;
644 noop_desc->hw->ctl = IOAT_DMA_DESCRIPTOR_NUL;
645 noop_desc->hw->src_addr = 0;
646 noop_desc->hw->dst_addr = 0;
648 ioat_chan->used_desc.next = ioat_chan->used_desc.next->next;
649 ioat_chan->pending++;
650 ioat_chan->dmacount++;
652 /* try to get a few more descriptors */
653 for (i = 16; i; i--) {
654 desc = ioat_dma_alloc_descriptor(ioat_chan, GFP_ATOMIC);
656 dev_err(&ioat_chan->device->pdev->dev,
660 list_add_tail(&desc->node, ioat_chan->used_desc.next);
663 = to_ioat_desc(desc->node.next)->async_tx.phys;
664 to_ioat_desc(desc->node.prev)->hw->next
665 = desc->async_tx.phys;
666 ioat_chan->desccount++;
669 ioat_chan->used_desc.next = noop_desc->node.next;
671 new = to_ioat_desc(ioat_chan->used_desc.next);
673 ioat_chan->used_desc.next = new->node.next;
675 if (ioat_chan->used_desc.prev == NULL)
676 ioat_chan->used_desc.prev = &new->node;
682 static struct ioat_desc_sw *ioat_dma_get_next_descriptor(
683 struct ioat_dma_chan *ioat_chan)
688 switch (ioat_chan->device->version) {
690 return ioat1_dma_get_next_descriptor(ioat_chan);
693 return ioat2_dma_get_next_descriptor(ioat_chan);
699 static struct dma_async_tx_descriptor *ioat1_dma_prep_memcpy(
700 struct dma_chan *chan,
706 struct ioat_dma_chan *ioat_chan = to_ioat_chan(chan);
707 struct ioat_desc_sw *new;
709 spin_lock_bh(&ioat_chan->desc_lock);
710 new = ioat_dma_get_next_descriptor(ioat_chan);
711 spin_unlock_bh(&ioat_chan->desc_lock);
717 return &new->async_tx;
722 static struct dma_async_tx_descriptor *ioat2_dma_prep_memcpy(
723 struct dma_chan *chan,
729 struct ioat_dma_chan *ioat_chan = to_ioat_chan(chan);
730 struct ioat_desc_sw *new;
732 spin_lock_bh(&ioat_chan->desc_lock);
733 new = ioat2_dma_get_next_descriptor(ioat_chan);
736 * leave ioat_chan->desc_lock set in ioat 2 path
737 * it will get unlocked at end of tx_submit
744 return &new->async_tx;
749 static void ioat_dma_cleanup_tasklet(unsigned long data)
751 struct ioat_dma_chan *chan = (void *)data;
752 ioat_dma_memcpy_cleanup(chan);
753 writew(IOAT_CHANCTRL_INT_DISABLE,
754 chan->reg_base + IOAT_CHANCTRL_OFFSET);
758 * ioat_dma_memcpy_cleanup - cleanup up finished descriptors
759 * @chan: ioat channel to be cleaned up
761 static void ioat_dma_memcpy_cleanup(struct ioat_dma_chan *ioat_chan)
763 unsigned long phys_complete;
764 struct ioat_desc_sw *desc, *_desc;
765 dma_cookie_t cookie = 0;
766 unsigned long desc_phys;
767 struct ioat_desc_sw *latest_desc;
769 prefetch(ioat_chan->completion_virt);
771 if (!spin_trylock_bh(&ioat_chan->cleanup_lock))
774 /* The completion writeback can happen at any time,
775 so reads by the driver need to be atomic operations
776 The descriptor physical addresses are limited to 32-bits
777 when the CPU can only do a 32-bit mov */
779 #if (BITS_PER_LONG == 64)
781 ioat_chan->completion_virt->full
782 & IOAT_CHANSTS_COMPLETED_DESCRIPTOR_ADDR;
785 ioat_chan->completion_virt->low & IOAT_LOW_COMPLETION_MASK;
788 if ((ioat_chan->completion_virt->full
789 & IOAT_CHANSTS_DMA_TRANSFER_STATUS) ==
790 IOAT_CHANSTS_DMA_TRANSFER_STATUS_HALTED) {
791 dev_err(&ioat_chan->device->pdev->dev,
792 "Channel halted, chanerr = %x\n",
793 readl(ioat_chan->reg_base + IOAT_CHANERR_OFFSET));
795 /* TODO do something to salvage the situation */
798 if (phys_complete == ioat_chan->last_completion) {
799 spin_unlock_bh(&ioat_chan->cleanup_lock);
804 spin_lock_bh(&ioat_chan->desc_lock);
805 switch (ioat_chan->device->version) {
807 list_for_each_entry_safe(desc, _desc,
808 &ioat_chan->used_desc, node) {
811 * Incoming DMA requests may use multiple descriptors,
812 * due to exceeding xfercap, perhaps. If so, only the
813 * last one will have a cookie, and require unmapping.
815 if (desc->async_tx.cookie) {
816 cookie = desc->async_tx.cookie;
819 * yes we are unmapping both _page and _single
820 * alloc'd regions with unmap_page. Is this
823 pci_unmap_page(ioat_chan->device->pdev,
824 pci_unmap_addr(desc, dst),
825 pci_unmap_len(desc, len),
827 pci_unmap_page(ioat_chan->device->pdev,
828 pci_unmap_addr(desc, src),
829 pci_unmap_len(desc, len),
832 if (desc->async_tx.callback) {
833 desc->async_tx.callback(desc->async_tx.callback_param);
834 desc->async_tx.callback = NULL;
838 if (desc->async_tx.phys != phys_complete) {
840 * a completed entry, but not the last, so clean
841 * up if the client is done with the descriptor
843 if (desc->async_tx.ack) {
844 list_del(&desc->node);
845 list_add_tail(&desc->node,
846 &ioat_chan->free_desc);
848 desc->async_tx.cookie = 0;
851 * last used desc. Do not remove, so we can
852 * append from it, but don't look at it next
855 desc->async_tx.cookie = 0;
857 /* TODO check status bits? */
863 /* has some other thread has already cleaned up? */
864 if (ioat_chan->used_desc.prev == NULL)
867 /* work backwards to find latest finished desc */
868 desc = to_ioat_desc(ioat_chan->used_desc.next);
871 desc = to_ioat_desc(desc->node.prev);
872 desc_phys = (unsigned long)desc->async_tx.phys
873 & IOAT_CHANSTS_COMPLETED_DESCRIPTOR_ADDR;
874 if (desc_phys == phys_complete) {
878 } while (&desc->node != ioat_chan->used_desc.prev);
880 if (latest_desc != NULL) {
882 /* work forwards to clear finished descriptors */
883 for (desc = to_ioat_desc(ioat_chan->used_desc.prev);
884 &desc->node != latest_desc->node.next &&
885 &desc->node != ioat_chan->used_desc.next;
886 desc = to_ioat_desc(desc->node.next)) {
887 if (desc->async_tx.cookie) {
888 cookie = desc->async_tx.cookie;
889 desc->async_tx.cookie = 0;
891 pci_unmap_page(ioat_chan->device->pdev,
892 pci_unmap_addr(desc, dst),
893 pci_unmap_len(desc, len),
895 pci_unmap_page(ioat_chan->device->pdev,
896 pci_unmap_addr(desc, src),
897 pci_unmap_len(desc, len),
900 if (desc->async_tx.callback) {
901 desc->async_tx.callback(desc->async_tx.callback_param);
902 desc->async_tx.callback = NULL;
907 /* move used.prev up beyond those that are finished */
908 if (&desc->node == ioat_chan->used_desc.next)
909 ioat_chan->used_desc.prev = NULL;
911 ioat_chan->used_desc.prev = &desc->node;
916 spin_unlock_bh(&ioat_chan->desc_lock);
918 ioat_chan->last_completion = phys_complete;
920 ioat_chan->completed_cookie = cookie;
922 spin_unlock_bh(&ioat_chan->cleanup_lock);
925 static void ioat_dma_dependency_added(struct dma_chan *chan)
927 struct ioat_dma_chan *ioat_chan = to_ioat_chan(chan);
928 spin_lock_bh(&ioat_chan->desc_lock);
929 if (ioat_chan->pending == 0) {
930 spin_unlock_bh(&ioat_chan->desc_lock);
931 ioat_dma_memcpy_cleanup(ioat_chan);
933 spin_unlock_bh(&ioat_chan->desc_lock);
937 * ioat_dma_is_complete - poll the status of a IOAT DMA transaction
938 * @chan: IOAT DMA channel handle
939 * @cookie: DMA transaction identifier
940 * @done: if not %NULL, updated with last completed transaction
941 * @used: if not %NULL, updated with last used transaction
943 static enum dma_status ioat_dma_is_complete(struct dma_chan *chan,
948 struct ioat_dma_chan *ioat_chan = to_ioat_chan(chan);
949 dma_cookie_t last_used;
950 dma_cookie_t last_complete;
953 last_used = chan->cookie;
954 last_complete = ioat_chan->completed_cookie;
957 *done = last_complete;
961 ret = dma_async_is_complete(cookie, last_complete, last_used);
962 if (ret == DMA_SUCCESS)
965 ioat_dma_memcpy_cleanup(ioat_chan);
967 last_used = chan->cookie;
968 last_complete = ioat_chan->completed_cookie;
971 *done = last_complete;
975 return dma_async_is_complete(cookie, last_complete, last_used);
978 static void ioat_dma_start_null_desc(struct ioat_dma_chan *ioat_chan)
980 struct ioat_desc_sw *desc;
982 spin_lock_bh(&ioat_chan->desc_lock);
984 desc = ioat_dma_get_next_descriptor(ioat_chan);
985 desc->hw->ctl = IOAT_DMA_DESCRIPTOR_NUL
986 | IOAT_DMA_DESCRIPTOR_CTL_INT_GN
987 | IOAT_DMA_DESCRIPTOR_CTL_CP_STS;
989 desc->hw->src_addr = 0;
990 desc->hw->dst_addr = 0;
991 desc->async_tx.ack = 1;
992 switch (ioat_chan->device->version) {
995 list_add_tail(&desc->node, &ioat_chan->used_desc);
997 writel(((u64) desc->async_tx.phys) & 0x00000000FFFFFFFF,
998 ioat_chan->reg_base + IOAT1_CHAINADDR_OFFSET_LOW);
999 writel(((u64) desc->async_tx.phys) >> 32,
1000 ioat_chan->reg_base + IOAT1_CHAINADDR_OFFSET_HIGH);
1002 writeb(IOAT_CHANCMD_START, ioat_chan->reg_base
1003 + IOAT_CHANCMD_OFFSET(ioat_chan->device->version));
1006 writel(((u64) desc->async_tx.phys) & 0x00000000FFFFFFFF,
1007 ioat_chan->reg_base + IOAT2_CHAINADDR_OFFSET_LOW);
1008 writel(((u64) desc->async_tx.phys) >> 32,
1009 ioat_chan->reg_base + IOAT2_CHAINADDR_OFFSET_HIGH);
1011 ioat_chan->dmacount++;
1012 __ioat2_dma_memcpy_issue_pending(ioat_chan);
1015 spin_unlock_bh(&ioat_chan->desc_lock);
1019 * Perform a IOAT transaction to verify the HW works.
1021 #define IOAT_TEST_SIZE 2000
1023 static void ioat_dma_test_callback(void *dma_async_param)
1025 printk(KERN_ERR "ioatdma: ioat_dma_test_callback(%p)\n",
1030 * ioat_dma_self_test - Perform a IOAT transaction to verify the HW works.
1031 * @device: device to be tested
1033 static int ioat_dma_self_test(struct ioatdma_device *device)
1038 struct dma_chan *dma_chan;
1039 struct dma_async_tx_descriptor *tx;
1040 dma_addr_t dma_dest, dma_src;
1041 dma_cookie_t cookie;
1044 src = kzalloc(sizeof(u8) * IOAT_TEST_SIZE, GFP_KERNEL);
1047 dest = kzalloc(sizeof(u8) * IOAT_TEST_SIZE, GFP_KERNEL);
1053 /* Fill in src buffer */
1054 for (i = 0; i < IOAT_TEST_SIZE; i++)
1057 /* Start copy, using first DMA channel */
1058 dma_chan = container_of(device->common.channels.next,
1061 if (device->common.device_alloc_chan_resources(dma_chan) < 1) {
1062 dev_err(&device->pdev->dev,
1063 "selftest cannot allocate chan resource\n");
1068 dma_src = dma_map_single(dma_chan->device->dev, src, IOAT_TEST_SIZE,
1070 dma_dest = dma_map_single(dma_chan->device->dev, dest, IOAT_TEST_SIZE,
1072 tx = device->common.device_prep_dma_memcpy(dma_chan, dma_dest, dma_src,
1075 dev_err(&device->pdev->dev,
1076 "Self-test prep failed, disabling\n");
1078 goto free_resources;
1082 tx->callback = ioat_dma_test_callback;
1083 tx->callback_param = (void *)0x8086;
1084 cookie = tx->tx_submit(tx);
1086 dev_err(&device->pdev->dev,
1087 "Self-test setup failed, disabling\n");
1089 goto free_resources;
1091 device->common.device_issue_pending(dma_chan);
1094 if (device->common.device_is_tx_complete(dma_chan, cookie, NULL, NULL)
1096 dev_err(&device->pdev->dev,
1097 "Self-test copy timed out, disabling\n");
1099 goto free_resources;
1101 if (memcmp(src, dest, IOAT_TEST_SIZE)) {
1102 dev_err(&device->pdev->dev,
1103 "Self-test copy failed compare, disabling\n");
1105 goto free_resources;
1109 device->common.device_free_chan_resources(dma_chan);
1116 static char ioat_interrupt_style[32] = "msix";
1117 module_param_string(ioat_interrupt_style, ioat_interrupt_style,
1118 sizeof(ioat_interrupt_style), 0644);
1119 MODULE_PARM_DESC(ioat_interrupt_style,
1120 "set ioat interrupt style: msix (default), "
1121 "msix-single-vector, msi, intx)");
1124 * ioat_dma_setup_interrupts - setup interrupt handler
1125 * @device: ioat device
1127 static int ioat_dma_setup_interrupts(struct ioatdma_device *device)
1129 struct ioat_dma_chan *ioat_chan;
1130 int err, i, j, msixcnt;
1133 if (!strcmp(ioat_interrupt_style, "msix"))
1135 if (!strcmp(ioat_interrupt_style, "msix-single-vector"))
1136 goto msix_single_vector;
1137 if (!strcmp(ioat_interrupt_style, "msi"))
1139 if (!strcmp(ioat_interrupt_style, "intx"))
1141 dev_err(&device->pdev->dev, "invalid ioat_interrupt_style %s\n",
1142 ioat_interrupt_style);
1146 /* The number of MSI-X vectors should equal the number of channels */
1147 msixcnt = device->common.chancnt;
1148 for (i = 0; i < msixcnt; i++)
1149 device->msix_entries[i].entry = i;
1151 err = pci_enable_msix(device->pdev, device->msix_entries, msixcnt);
1155 goto msix_single_vector;
1157 for (i = 0; i < msixcnt; i++) {
1158 ioat_chan = ioat_lookup_chan_by_index(device, i);
1159 err = request_irq(device->msix_entries[i].vector,
1160 ioat_dma_do_interrupt_msix,
1161 0, "ioat-msix", ioat_chan);
1163 for (j = 0; j < i; j++) {
1165 ioat_lookup_chan_by_index(device, j);
1166 free_irq(device->msix_entries[j].vector,
1169 goto msix_single_vector;
1172 intrctrl |= IOAT_INTRCTRL_MSIX_VECTOR_CONTROL;
1173 device->irq_mode = msix_multi_vector;
1177 device->msix_entries[0].entry = 0;
1178 err = pci_enable_msix(device->pdev, device->msix_entries, 1);
1182 err = request_irq(device->msix_entries[0].vector, ioat_dma_do_interrupt,
1183 0, "ioat-msix", device);
1185 pci_disable_msix(device->pdev);
1188 device->irq_mode = msix_single_vector;
1192 err = pci_enable_msi(device->pdev);
1196 err = request_irq(device->pdev->irq, ioat_dma_do_interrupt,
1197 0, "ioat-msi", device);
1199 pci_disable_msi(device->pdev);
1203 * CB 1.2 devices need a bit set in configuration space to enable MSI
1205 if (device->version == IOAT_VER_1_2) {
1207 pci_read_config_dword(device->pdev,
1208 IOAT_PCI_DMACTRL_OFFSET, &dmactrl);
1209 dmactrl |= IOAT_PCI_DMACTRL_MSI_EN;
1210 pci_write_config_dword(device->pdev,
1211 IOAT_PCI_DMACTRL_OFFSET, dmactrl);
1213 device->irq_mode = msi;
1217 err = request_irq(device->pdev->irq, ioat_dma_do_interrupt,
1218 IRQF_SHARED, "ioat-intx", device);
1221 device->irq_mode = intx;
1224 intrctrl |= IOAT_INTRCTRL_MASTER_INT_EN;
1225 writeb(intrctrl, device->reg_base + IOAT_INTRCTRL_OFFSET);
1229 /* Disable all interrupt generation */
1230 writeb(0, device->reg_base + IOAT_INTRCTRL_OFFSET);
1231 dev_err(&device->pdev->dev, "no usable interrupts\n");
1232 device->irq_mode = none;
1237 * ioat_dma_remove_interrupts - remove whatever interrupts were set
1238 * @device: ioat device
1240 static void ioat_dma_remove_interrupts(struct ioatdma_device *device)
1242 struct ioat_dma_chan *ioat_chan;
1245 /* Disable all interrupt generation */
1246 writeb(0, device->reg_base + IOAT_INTRCTRL_OFFSET);
1248 switch (device->irq_mode) {
1249 case msix_multi_vector:
1250 for (i = 0; i < device->common.chancnt; i++) {
1251 ioat_chan = ioat_lookup_chan_by_index(device, i);
1252 free_irq(device->msix_entries[i].vector, ioat_chan);
1254 pci_disable_msix(device->pdev);
1256 case msix_single_vector:
1257 free_irq(device->msix_entries[0].vector, device);
1258 pci_disable_msix(device->pdev);
1261 free_irq(device->pdev->irq, device);
1262 pci_disable_msi(device->pdev);
1265 free_irq(device->pdev->irq, device);
1268 dev_warn(&device->pdev->dev,
1269 "call to %s without interrupts setup\n", __func__);
1271 device->irq_mode = none;
1274 struct ioatdma_device *ioat_dma_probe(struct pci_dev *pdev,
1275 void __iomem *iobase)
1278 struct ioatdma_device *device;
1280 device = kzalloc(sizeof(*device), GFP_KERNEL);
1285 device->pdev = pdev;
1286 device->reg_base = iobase;
1287 device->version = readb(device->reg_base + IOAT_VER_OFFSET);
1289 /* DMA coherent memory pool for DMA descriptor allocations */
1290 device->dma_pool = pci_pool_create("dma_desc_pool", pdev,
1291 sizeof(struct ioat_dma_descriptor),
1293 if (!device->dma_pool) {
1298 device->completion_pool = pci_pool_create("completion_pool", pdev,
1299 sizeof(u64), SMP_CACHE_BYTES,
1301 if (!device->completion_pool) {
1303 goto err_completion_pool;
1306 INIT_LIST_HEAD(&device->common.channels);
1307 ioat_dma_enumerate_channels(device);
1309 device->common.device_alloc_chan_resources =
1310 ioat_dma_alloc_chan_resources;
1311 device->common.device_free_chan_resources =
1312 ioat_dma_free_chan_resources;
1313 device->common.dev = &pdev->dev;
1315 dma_cap_set(DMA_MEMCPY, device->common.cap_mask);
1316 device->common.device_is_tx_complete = ioat_dma_is_complete;
1317 device->common.device_dependency_added = ioat_dma_dependency_added;
1318 switch (device->version) {
1320 device->common.device_prep_dma_memcpy = ioat1_dma_prep_memcpy;
1321 device->common.device_issue_pending =
1322 ioat1_dma_memcpy_issue_pending;
1325 device->common.device_prep_dma_memcpy = ioat2_dma_prep_memcpy;
1326 device->common.device_issue_pending =
1327 ioat2_dma_memcpy_issue_pending;
1331 dev_err(&device->pdev->dev,
1332 "Intel(R) I/OAT DMA Engine found,"
1333 " %d channels, device version 0x%02x, driver version %s\n",
1334 device->common.chancnt, device->version, IOAT_DMA_VERSION);
1336 err = ioat_dma_setup_interrupts(device);
1338 goto err_setup_interrupts;
1340 err = ioat_dma_self_test(device);
1344 dma_async_device_register(&device->common);
1349 ioat_dma_remove_interrupts(device);
1350 err_setup_interrupts:
1351 pci_pool_destroy(device->completion_pool);
1352 err_completion_pool:
1353 pci_pool_destroy(device->dma_pool);
1358 "Intel(R) I/OAT DMA Engine initialization failed\n");
1362 void ioat_dma_remove(struct ioatdma_device *device)
1364 struct dma_chan *chan, *_chan;
1365 struct ioat_dma_chan *ioat_chan;
1367 ioat_dma_remove_interrupts(device);
1369 dma_async_device_unregister(&device->common);
1371 pci_pool_destroy(device->dma_pool);
1372 pci_pool_destroy(device->completion_pool);
1374 iounmap(device->reg_base);
1375 pci_release_regions(device->pdev);
1376 pci_disable_device(device->pdev);
1378 list_for_each_entry_safe(chan, _chan,
1379 &device->common.channels, device_node) {
1380 ioat_chan = to_ioat_chan(chan);
1381 list_del(&chan->device_node);