mm: fix assertion
[linux-2.6/linux-acpi-2.6/ibm-acpi-2.6.git] / drivers / dma / ioat_dma.c
blobd62311f049a23849656928676cd4874fc294e881
1 /*
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
12 * more details.
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
25 * copy operations.
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 "ioatdma.h"
37 #include "ioatdma_registers.h"
38 #include "ioatdma_hw.h"
40 #define to_ioat_chan(chan) container_of(chan, struct ioat_dma_chan, common)
41 #define to_ioatdma_device(dev) container_of(dev, struct ioatdma_device, common)
42 #define to_ioat_desc(lh) container_of(lh, struct ioat_desc_sw, node)
43 #define tx_to_ioat_desc(tx) container_of(tx, struct ioat_desc_sw, async_tx)
45 #define chan_num(ch) ((int)((ch)->reg_base - (ch)->device->reg_base) / 0x80)
46 static int ioat_pending_level = 4;
47 module_param(ioat_pending_level, int, 0644);
48 MODULE_PARM_DESC(ioat_pending_level,
49 "high-water mark for pushing ioat descriptors (default: 4)");
51 #define RESET_DELAY msecs_to_jiffies(100)
52 #define WATCHDOG_DELAY round_jiffies(msecs_to_jiffies(2000))
53 static void ioat_dma_chan_reset_part2(struct work_struct *work);
54 static void ioat_dma_chan_watchdog(struct work_struct *work);
57 * workaround for IOAT ver.3.0 null descriptor issue
58 * (channel returns error when size is 0)
60 #define NULL_DESC_BUFFER_SIZE 1
62 /* internal functions */
63 static void ioat_dma_start_null_desc(struct ioat_dma_chan *ioat_chan);
64 static void ioat_dma_memcpy_cleanup(struct ioat_dma_chan *ioat_chan);
66 static struct ioat_desc_sw *
67 ioat1_dma_get_next_descriptor(struct ioat_dma_chan *ioat_chan);
68 static struct ioat_desc_sw *
69 ioat2_dma_get_next_descriptor(struct ioat_dma_chan *ioat_chan);
71 static inline struct ioat_dma_chan *ioat_lookup_chan_by_index(
72 struct ioatdma_device *device,
73 int index)
75 return device->idx[index];
78 /**
79 * ioat_dma_do_interrupt - handler used for single vector interrupt mode
80 * @irq: interrupt id
81 * @data: interrupt data
83 static irqreturn_t ioat_dma_do_interrupt(int irq, void *data)
85 struct ioatdma_device *instance = data;
86 struct ioat_dma_chan *ioat_chan;
87 unsigned long attnstatus;
88 int bit;
89 u8 intrctrl;
91 intrctrl = readb(instance->reg_base + IOAT_INTRCTRL_OFFSET);
93 if (!(intrctrl & IOAT_INTRCTRL_MASTER_INT_EN))
94 return IRQ_NONE;
96 if (!(intrctrl & IOAT_INTRCTRL_INT_STATUS)) {
97 writeb(intrctrl, instance->reg_base + IOAT_INTRCTRL_OFFSET);
98 return IRQ_NONE;
101 attnstatus = readl(instance->reg_base + IOAT_ATTNSTATUS_OFFSET);
102 for_each_bit(bit, &attnstatus, BITS_PER_LONG) {
103 ioat_chan = ioat_lookup_chan_by_index(instance, bit);
104 tasklet_schedule(&ioat_chan->cleanup_task);
107 writeb(intrctrl, instance->reg_base + IOAT_INTRCTRL_OFFSET);
108 return IRQ_HANDLED;
112 * ioat_dma_do_interrupt_msix - handler used for vector-per-channel interrupt mode
113 * @irq: interrupt id
114 * @data: interrupt data
116 static irqreturn_t ioat_dma_do_interrupt_msix(int irq, void *data)
118 struct ioat_dma_chan *ioat_chan = data;
120 tasklet_schedule(&ioat_chan->cleanup_task);
122 return IRQ_HANDLED;
125 static void ioat_dma_cleanup_tasklet(unsigned long data);
128 * ioat_dma_enumerate_channels - find and initialize the device's channels
129 * @device: the device to be enumerated
131 static int ioat_dma_enumerate_channels(struct ioatdma_device *device)
133 u8 xfercap_scale;
134 u32 xfercap;
135 int i;
136 struct ioat_dma_chan *ioat_chan;
139 * IOAT ver.3 workarounds
141 if (device->version == IOAT_VER_3_0) {
142 u32 chan_err_mask;
143 u16 dev_id;
144 u32 dmauncerrsts;
147 * Write CHANERRMSK_INT with 3E07h to mask out the errors
148 * that can cause stability issues for IOAT ver.3
150 chan_err_mask = 0x3E07;
151 pci_write_config_dword(device->pdev,
152 IOAT_PCI_CHANERRMASK_INT_OFFSET,
153 chan_err_mask);
156 * Clear DMAUNCERRSTS Cfg-Reg Parity Error status bit
157 * (workaround for spurious config parity error after restart)
159 pci_read_config_word(device->pdev,
160 IOAT_PCI_DEVICE_ID_OFFSET,
161 &dev_id);
162 if (dev_id == PCI_DEVICE_ID_INTEL_IOAT_TBG0) {
163 dmauncerrsts = 0x10;
164 pci_write_config_dword(device->pdev,
165 IOAT_PCI_DMAUNCERRSTS_OFFSET,
166 dmauncerrsts);
170 device->common.chancnt = readb(device->reg_base + IOAT_CHANCNT_OFFSET);
171 xfercap_scale = readb(device->reg_base + IOAT_XFERCAP_OFFSET);
172 xfercap = (xfercap_scale == 0 ? -1 : (1UL << xfercap_scale));
174 for (i = 0; i < device->common.chancnt; i++) {
175 ioat_chan = kzalloc(sizeof(*ioat_chan), GFP_KERNEL);
176 if (!ioat_chan) {
177 device->common.chancnt = i;
178 break;
181 ioat_chan->device = device;
182 ioat_chan->reg_base = device->reg_base + (0x80 * (i + 1));
183 ioat_chan->xfercap = xfercap;
184 ioat_chan->desccount = 0;
185 INIT_DELAYED_WORK(&ioat_chan->work, ioat_dma_chan_reset_part2);
186 if (ioat_chan->device->version != IOAT_VER_1_2) {
187 writel(IOAT_DCACTRL_CMPL_WRITE_ENABLE
188 | IOAT_DMA_DCA_ANY_CPU,
189 ioat_chan->reg_base + IOAT_DCACTRL_OFFSET);
191 spin_lock_init(&ioat_chan->cleanup_lock);
192 spin_lock_init(&ioat_chan->desc_lock);
193 INIT_LIST_HEAD(&ioat_chan->free_desc);
194 INIT_LIST_HEAD(&ioat_chan->used_desc);
195 /* This should be made common somewhere in dmaengine.c */
196 ioat_chan->common.device = &device->common;
197 list_add_tail(&ioat_chan->common.device_node,
198 &device->common.channels);
199 device->idx[i] = ioat_chan;
200 tasklet_init(&ioat_chan->cleanup_task,
201 ioat_dma_cleanup_tasklet,
202 (unsigned long) ioat_chan);
203 tasklet_disable(&ioat_chan->cleanup_task);
205 return device->common.chancnt;
209 * ioat_dma_memcpy_issue_pending - push potentially unrecognized appended
210 * descriptors to hw
211 * @chan: DMA channel handle
213 static inline void __ioat1_dma_memcpy_issue_pending(
214 struct ioat_dma_chan *ioat_chan)
216 ioat_chan->pending = 0;
217 writeb(IOAT_CHANCMD_APPEND, ioat_chan->reg_base + IOAT1_CHANCMD_OFFSET);
220 static void ioat1_dma_memcpy_issue_pending(struct dma_chan *chan)
222 struct ioat_dma_chan *ioat_chan = to_ioat_chan(chan);
224 if (ioat_chan->pending > 0) {
225 spin_lock_bh(&ioat_chan->desc_lock);
226 __ioat1_dma_memcpy_issue_pending(ioat_chan);
227 spin_unlock_bh(&ioat_chan->desc_lock);
231 static inline void __ioat2_dma_memcpy_issue_pending(
232 struct ioat_dma_chan *ioat_chan)
234 ioat_chan->pending = 0;
235 writew(ioat_chan->dmacount,
236 ioat_chan->reg_base + IOAT_CHAN_DMACOUNT_OFFSET);
239 static void ioat2_dma_memcpy_issue_pending(struct dma_chan *chan)
241 struct ioat_dma_chan *ioat_chan = to_ioat_chan(chan);
243 if (ioat_chan->pending > 0) {
244 spin_lock_bh(&ioat_chan->desc_lock);
245 __ioat2_dma_memcpy_issue_pending(ioat_chan);
246 spin_unlock_bh(&ioat_chan->desc_lock);
252 * ioat_dma_chan_reset_part2 - reinit the channel after a reset
254 static void ioat_dma_chan_reset_part2(struct work_struct *work)
256 struct ioat_dma_chan *ioat_chan =
257 container_of(work, struct ioat_dma_chan, work.work);
258 struct ioat_desc_sw *desc;
260 spin_lock_bh(&ioat_chan->cleanup_lock);
261 spin_lock_bh(&ioat_chan->desc_lock);
263 ioat_chan->completion_virt->low = 0;
264 ioat_chan->completion_virt->high = 0;
265 ioat_chan->pending = 0;
268 * count the descriptors waiting, and be sure to do it
269 * right for both the CB1 line and the CB2 ring
271 ioat_chan->dmacount = 0;
272 if (ioat_chan->used_desc.prev) {
273 desc = to_ioat_desc(ioat_chan->used_desc.prev);
274 do {
275 ioat_chan->dmacount++;
276 desc = to_ioat_desc(desc->node.next);
277 } while (&desc->node != ioat_chan->used_desc.next);
281 * write the new starting descriptor address
282 * this puts channel engine into ARMED state
284 desc = to_ioat_desc(ioat_chan->used_desc.prev);
285 switch (ioat_chan->device->version) {
286 case IOAT_VER_1_2:
287 writel(((u64) desc->async_tx.phys) & 0x00000000FFFFFFFF,
288 ioat_chan->reg_base + IOAT1_CHAINADDR_OFFSET_LOW);
289 writel(((u64) desc->async_tx.phys) >> 32,
290 ioat_chan->reg_base + IOAT1_CHAINADDR_OFFSET_HIGH);
292 writeb(IOAT_CHANCMD_START, ioat_chan->reg_base
293 + IOAT_CHANCMD_OFFSET(ioat_chan->device->version));
294 break;
295 case IOAT_VER_2_0:
296 writel(((u64) desc->async_tx.phys) & 0x00000000FFFFFFFF,
297 ioat_chan->reg_base + IOAT2_CHAINADDR_OFFSET_LOW);
298 writel(((u64) desc->async_tx.phys) >> 32,
299 ioat_chan->reg_base + IOAT2_CHAINADDR_OFFSET_HIGH);
301 /* tell the engine to go with what's left to be done */
302 writew(ioat_chan->dmacount,
303 ioat_chan->reg_base + IOAT_CHAN_DMACOUNT_OFFSET);
305 break;
307 dev_err(&ioat_chan->device->pdev->dev,
308 "chan%d reset - %d descs waiting, %d total desc\n",
309 chan_num(ioat_chan), ioat_chan->dmacount, ioat_chan->desccount);
311 spin_unlock_bh(&ioat_chan->desc_lock);
312 spin_unlock_bh(&ioat_chan->cleanup_lock);
316 * ioat_dma_reset_channel - restart a channel
317 * @ioat_chan: IOAT DMA channel handle
319 static void ioat_dma_reset_channel(struct ioat_dma_chan *ioat_chan)
321 u32 chansts, chanerr;
323 if (!ioat_chan->used_desc.prev)
324 return;
326 chanerr = readl(ioat_chan->reg_base + IOAT_CHANERR_OFFSET);
327 chansts = (ioat_chan->completion_virt->low
328 & IOAT_CHANSTS_DMA_TRANSFER_STATUS);
329 if (chanerr) {
330 dev_err(&ioat_chan->device->pdev->dev,
331 "chan%d, CHANSTS = 0x%08x CHANERR = 0x%04x, clearing\n",
332 chan_num(ioat_chan), chansts, chanerr);
333 writel(chanerr, ioat_chan->reg_base + IOAT_CHANERR_OFFSET);
337 * whack it upside the head with a reset
338 * and wait for things to settle out.
339 * force the pending count to a really big negative
340 * to make sure no one forces an issue_pending
341 * while we're waiting.
344 spin_lock_bh(&ioat_chan->desc_lock);
345 ioat_chan->pending = INT_MIN;
346 writeb(IOAT_CHANCMD_RESET,
347 ioat_chan->reg_base
348 + IOAT_CHANCMD_OFFSET(ioat_chan->device->version));
349 spin_unlock_bh(&ioat_chan->desc_lock);
351 /* schedule the 2nd half instead of sleeping a long time */
352 schedule_delayed_work(&ioat_chan->work, RESET_DELAY);
356 * ioat_dma_chan_watchdog - watch for stuck channels
358 static void ioat_dma_chan_watchdog(struct work_struct *work)
360 struct ioatdma_device *device =
361 container_of(work, struct ioatdma_device, work.work);
362 struct ioat_dma_chan *ioat_chan;
363 int i;
365 union {
366 u64 full;
367 struct {
368 u32 low;
369 u32 high;
371 } completion_hw;
372 unsigned long compl_desc_addr_hw;
374 for (i = 0; i < device->common.chancnt; i++) {
375 ioat_chan = ioat_lookup_chan_by_index(device, i);
377 if (ioat_chan->device->version == IOAT_VER_1_2
378 /* have we started processing anything yet */
379 && ioat_chan->last_completion
380 /* have we completed any since last watchdog cycle? */
381 && (ioat_chan->last_completion ==
382 ioat_chan->watchdog_completion)
383 /* has TCP stuck on one cookie since last watchdog? */
384 && (ioat_chan->watchdog_tcp_cookie ==
385 ioat_chan->watchdog_last_tcp_cookie)
386 && (ioat_chan->watchdog_tcp_cookie !=
387 ioat_chan->completed_cookie)
388 /* is there something in the chain to be processed? */
389 /* CB1 chain always has at least the last one processed */
390 && (ioat_chan->used_desc.prev != ioat_chan->used_desc.next)
391 && ioat_chan->pending == 0) {
394 * check CHANSTS register for completed
395 * descriptor address.
396 * if it is different than completion writeback,
397 * it is not zero
398 * and it has changed since the last watchdog
399 * we can assume that channel
400 * is still working correctly
401 * and the problem is in completion writeback.
402 * update completion writeback
403 * with actual CHANSTS value
404 * else
405 * try resetting the channel
408 completion_hw.low = readl(ioat_chan->reg_base +
409 IOAT_CHANSTS_OFFSET_LOW(ioat_chan->device->version));
410 completion_hw.high = readl(ioat_chan->reg_base +
411 IOAT_CHANSTS_OFFSET_HIGH(ioat_chan->device->version));
412 #if (BITS_PER_LONG == 64)
413 compl_desc_addr_hw =
414 completion_hw.full
415 & IOAT_CHANSTS_COMPLETED_DESCRIPTOR_ADDR;
416 #else
417 compl_desc_addr_hw =
418 completion_hw.low & IOAT_LOW_COMPLETION_MASK;
419 #endif
421 if ((compl_desc_addr_hw != 0)
422 && (compl_desc_addr_hw != ioat_chan->watchdog_completion)
423 && (compl_desc_addr_hw != ioat_chan->last_compl_desc_addr_hw)) {
424 ioat_chan->last_compl_desc_addr_hw = compl_desc_addr_hw;
425 ioat_chan->completion_virt->low = completion_hw.low;
426 ioat_chan->completion_virt->high = completion_hw.high;
427 } else {
428 ioat_dma_reset_channel(ioat_chan);
429 ioat_chan->watchdog_completion = 0;
430 ioat_chan->last_compl_desc_addr_hw = 0;
434 * for version 2.0 if there are descriptors yet to be processed
435 * and the last completed hasn't changed since the last watchdog
436 * if they haven't hit the pending level
437 * issue the pending to push them through
438 * else
439 * try resetting the channel
441 } else if (ioat_chan->device->version == IOAT_VER_2_0
442 && ioat_chan->used_desc.prev
443 && ioat_chan->last_completion
444 && ioat_chan->last_completion == ioat_chan->watchdog_completion) {
446 if (ioat_chan->pending < ioat_pending_level)
447 ioat2_dma_memcpy_issue_pending(&ioat_chan->common);
448 else {
449 ioat_dma_reset_channel(ioat_chan);
450 ioat_chan->watchdog_completion = 0;
452 } else {
453 ioat_chan->last_compl_desc_addr_hw = 0;
454 ioat_chan->watchdog_completion
455 = ioat_chan->last_completion;
458 ioat_chan->watchdog_last_tcp_cookie =
459 ioat_chan->watchdog_tcp_cookie;
462 schedule_delayed_work(&device->work, WATCHDOG_DELAY);
465 static dma_cookie_t ioat1_tx_submit(struct dma_async_tx_descriptor *tx)
467 struct ioat_dma_chan *ioat_chan = to_ioat_chan(tx->chan);
468 struct ioat_desc_sw *first = tx_to_ioat_desc(tx);
469 struct ioat_desc_sw *prev, *new;
470 struct ioat_dma_descriptor *hw;
471 dma_cookie_t cookie;
472 LIST_HEAD(new_chain);
473 u32 copy;
474 size_t len;
475 dma_addr_t src, dst;
476 unsigned long orig_flags;
477 unsigned int desc_count = 0;
479 /* src and dest and len are stored in the initial descriptor */
480 len = first->len;
481 src = first->src;
482 dst = first->dst;
483 orig_flags = first->async_tx.flags;
484 new = first;
486 spin_lock_bh(&ioat_chan->desc_lock);
487 prev = to_ioat_desc(ioat_chan->used_desc.prev);
488 prefetch(prev->hw);
489 do {
490 copy = min_t(size_t, len, ioat_chan->xfercap);
492 async_tx_ack(&new->async_tx);
494 hw = new->hw;
495 hw->size = copy;
496 hw->ctl = 0;
497 hw->src_addr = src;
498 hw->dst_addr = dst;
499 hw->next = 0;
501 /* chain together the physical address list for the HW */
502 wmb();
503 prev->hw->next = (u64) new->async_tx.phys;
505 len -= copy;
506 dst += copy;
507 src += copy;
509 list_add_tail(&new->node, &new_chain);
510 desc_count++;
511 prev = new;
512 } while (len && (new = ioat1_dma_get_next_descriptor(ioat_chan)));
514 if (!new) {
515 dev_err(&ioat_chan->device->pdev->dev,
516 "tx submit failed\n");
517 spin_unlock_bh(&ioat_chan->desc_lock);
518 return -ENOMEM;
521 hw->ctl = IOAT_DMA_DESCRIPTOR_CTL_CP_STS;
522 if (first->async_tx.callback) {
523 hw->ctl |= IOAT_DMA_DESCRIPTOR_CTL_INT_GN;
524 if (first != new) {
525 /* move callback into to last desc */
526 new->async_tx.callback = first->async_tx.callback;
527 new->async_tx.callback_param
528 = first->async_tx.callback_param;
529 first->async_tx.callback = NULL;
530 first->async_tx.callback_param = NULL;
534 new->tx_cnt = desc_count;
535 new->async_tx.flags = orig_flags; /* client is in control of this ack */
537 /* store the original values for use in later cleanup */
538 if (new != first) {
539 new->src = first->src;
540 new->dst = first->dst;
541 new->len = first->len;
544 /* cookie incr and addition to used_list must be atomic */
545 cookie = ioat_chan->common.cookie;
546 cookie++;
547 if (cookie < 0)
548 cookie = 1;
549 ioat_chan->common.cookie = new->async_tx.cookie = cookie;
551 /* write address into NextDescriptor field of last desc in chain */
552 to_ioat_desc(ioat_chan->used_desc.prev)->hw->next =
553 first->async_tx.phys;
554 list_splice_tail(&new_chain, &ioat_chan->used_desc);
556 ioat_chan->dmacount += desc_count;
557 ioat_chan->pending += desc_count;
558 if (ioat_chan->pending >= ioat_pending_level)
559 __ioat1_dma_memcpy_issue_pending(ioat_chan);
560 spin_unlock_bh(&ioat_chan->desc_lock);
562 return cookie;
565 static dma_cookie_t ioat2_tx_submit(struct dma_async_tx_descriptor *tx)
567 struct ioat_dma_chan *ioat_chan = to_ioat_chan(tx->chan);
568 struct ioat_desc_sw *first = tx_to_ioat_desc(tx);
569 struct ioat_desc_sw *new;
570 struct ioat_dma_descriptor *hw;
571 dma_cookie_t cookie;
572 u32 copy;
573 size_t len;
574 dma_addr_t src, dst;
575 unsigned long orig_flags;
576 unsigned int desc_count = 0;
578 /* src and dest and len are stored in the initial descriptor */
579 len = first->len;
580 src = first->src;
581 dst = first->dst;
582 orig_flags = first->async_tx.flags;
583 new = first;
586 * ioat_chan->desc_lock is still in force in version 2 path
587 * it gets unlocked at end of this function
589 do {
590 copy = min_t(size_t, len, ioat_chan->xfercap);
592 async_tx_ack(&new->async_tx);
594 hw = new->hw;
595 hw->size = copy;
596 hw->ctl = 0;
597 hw->src_addr = src;
598 hw->dst_addr = dst;
600 len -= copy;
601 dst += copy;
602 src += copy;
603 desc_count++;
604 } while (len && (new = ioat2_dma_get_next_descriptor(ioat_chan)));
606 if (!new) {
607 dev_err(&ioat_chan->device->pdev->dev,
608 "tx submit failed\n");
609 spin_unlock_bh(&ioat_chan->desc_lock);
610 return -ENOMEM;
613 hw->ctl |= IOAT_DMA_DESCRIPTOR_CTL_CP_STS;
614 if (first->async_tx.callback) {
615 hw->ctl |= IOAT_DMA_DESCRIPTOR_CTL_INT_GN;
616 if (first != new) {
617 /* move callback into to last desc */
618 new->async_tx.callback = first->async_tx.callback;
619 new->async_tx.callback_param
620 = first->async_tx.callback_param;
621 first->async_tx.callback = NULL;
622 first->async_tx.callback_param = NULL;
626 new->tx_cnt = desc_count;
627 new->async_tx.flags = orig_flags; /* client is in control of this ack */
629 /* store the original values for use in later cleanup */
630 if (new != first) {
631 new->src = first->src;
632 new->dst = first->dst;
633 new->len = first->len;
636 /* cookie incr and addition to used_list must be atomic */
637 cookie = ioat_chan->common.cookie;
638 cookie++;
639 if (cookie < 0)
640 cookie = 1;
641 ioat_chan->common.cookie = new->async_tx.cookie = cookie;
643 ioat_chan->dmacount += desc_count;
644 ioat_chan->pending += desc_count;
645 if (ioat_chan->pending >= ioat_pending_level)
646 __ioat2_dma_memcpy_issue_pending(ioat_chan);
647 spin_unlock_bh(&ioat_chan->desc_lock);
649 return cookie;
653 * ioat_dma_alloc_descriptor - allocate and return a sw and hw descriptor pair
654 * @ioat_chan: the channel supplying the memory pool for the descriptors
655 * @flags: allocation flags
657 static struct ioat_desc_sw *ioat_dma_alloc_descriptor(
658 struct ioat_dma_chan *ioat_chan,
659 gfp_t flags)
661 struct ioat_dma_descriptor *desc;
662 struct ioat_desc_sw *desc_sw;
663 struct ioatdma_device *ioatdma_device;
664 dma_addr_t phys;
666 ioatdma_device = to_ioatdma_device(ioat_chan->common.device);
667 desc = pci_pool_alloc(ioatdma_device->dma_pool, flags, &phys);
668 if (unlikely(!desc))
669 return NULL;
671 desc_sw = kzalloc(sizeof(*desc_sw), flags);
672 if (unlikely(!desc_sw)) {
673 pci_pool_free(ioatdma_device->dma_pool, desc, phys);
674 return NULL;
677 memset(desc, 0, sizeof(*desc));
678 dma_async_tx_descriptor_init(&desc_sw->async_tx, &ioat_chan->common);
679 switch (ioat_chan->device->version) {
680 case IOAT_VER_1_2:
681 desc_sw->async_tx.tx_submit = ioat1_tx_submit;
682 break;
683 case IOAT_VER_2_0:
684 case IOAT_VER_3_0:
685 desc_sw->async_tx.tx_submit = ioat2_tx_submit;
686 break;
688 INIT_LIST_HEAD(&desc_sw->async_tx.tx_list);
690 desc_sw->hw = desc;
691 desc_sw->async_tx.phys = phys;
693 return desc_sw;
696 static int ioat_initial_desc_count = 256;
697 module_param(ioat_initial_desc_count, int, 0644);
698 MODULE_PARM_DESC(ioat_initial_desc_count,
699 "initial descriptors per channel (default: 256)");
702 * ioat2_dma_massage_chan_desc - link the descriptors into a circle
703 * @ioat_chan: the channel to be massaged
705 static void ioat2_dma_massage_chan_desc(struct ioat_dma_chan *ioat_chan)
707 struct ioat_desc_sw *desc, *_desc;
709 /* setup used_desc */
710 ioat_chan->used_desc.next = ioat_chan->free_desc.next;
711 ioat_chan->used_desc.prev = NULL;
713 /* pull free_desc out of the circle so that every node is a hw
714 * descriptor, but leave it pointing to the list
716 ioat_chan->free_desc.prev->next = ioat_chan->free_desc.next;
717 ioat_chan->free_desc.next->prev = ioat_chan->free_desc.prev;
719 /* circle link the hw descriptors */
720 desc = to_ioat_desc(ioat_chan->free_desc.next);
721 desc->hw->next = to_ioat_desc(desc->node.next)->async_tx.phys;
722 list_for_each_entry_safe(desc, _desc, ioat_chan->free_desc.next, node) {
723 desc->hw->next = to_ioat_desc(desc->node.next)->async_tx.phys;
728 * ioat_dma_alloc_chan_resources - returns the number of allocated descriptors
729 * @chan: the channel to be filled out
731 static int ioat_dma_alloc_chan_resources(struct dma_chan *chan,
732 struct dma_client *client)
734 struct ioat_dma_chan *ioat_chan = to_ioat_chan(chan);
735 struct ioat_desc_sw *desc;
736 u16 chanctrl;
737 u32 chanerr;
738 int i;
739 LIST_HEAD(tmp_list);
741 /* have we already been set up? */
742 if (!list_empty(&ioat_chan->free_desc))
743 return ioat_chan->desccount;
745 /* Setup register to interrupt and write completion status on error */
746 chanctrl = IOAT_CHANCTRL_ERR_INT_EN |
747 IOAT_CHANCTRL_ANY_ERR_ABORT_EN |
748 IOAT_CHANCTRL_ERR_COMPLETION_EN;
749 writew(chanctrl, ioat_chan->reg_base + IOAT_CHANCTRL_OFFSET);
751 chanerr = readl(ioat_chan->reg_base + IOAT_CHANERR_OFFSET);
752 if (chanerr) {
753 dev_err(&ioat_chan->device->pdev->dev,
754 "CHANERR = %x, clearing\n", chanerr);
755 writel(chanerr, ioat_chan->reg_base + IOAT_CHANERR_OFFSET);
758 /* Allocate descriptors */
759 for (i = 0; i < ioat_initial_desc_count; i++) {
760 desc = ioat_dma_alloc_descriptor(ioat_chan, GFP_KERNEL);
761 if (!desc) {
762 dev_err(&ioat_chan->device->pdev->dev,
763 "Only %d initial descriptors\n", i);
764 break;
766 list_add_tail(&desc->node, &tmp_list);
768 spin_lock_bh(&ioat_chan->desc_lock);
769 ioat_chan->desccount = i;
770 list_splice(&tmp_list, &ioat_chan->free_desc);
771 if (ioat_chan->device->version != IOAT_VER_1_2)
772 ioat2_dma_massage_chan_desc(ioat_chan);
773 spin_unlock_bh(&ioat_chan->desc_lock);
775 /* allocate a completion writeback area */
776 /* doing 2 32bit writes to mmio since 1 64b write doesn't work */
777 ioat_chan->completion_virt =
778 pci_pool_alloc(ioat_chan->device->completion_pool,
779 GFP_KERNEL,
780 &ioat_chan->completion_addr);
781 memset(ioat_chan->completion_virt, 0,
782 sizeof(*ioat_chan->completion_virt));
783 writel(((u64) ioat_chan->completion_addr) & 0x00000000FFFFFFFF,
784 ioat_chan->reg_base + IOAT_CHANCMP_OFFSET_LOW);
785 writel(((u64) ioat_chan->completion_addr) >> 32,
786 ioat_chan->reg_base + IOAT_CHANCMP_OFFSET_HIGH);
788 tasklet_enable(&ioat_chan->cleanup_task);
789 ioat_dma_start_null_desc(ioat_chan); /* give chain to dma device */
790 return ioat_chan->desccount;
794 * ioat_dma_free_chan_resources - release all the descriptors
795 * @chan: the channel to be cleaned
797 static void ioat_dma_free_chan_resources(struct dma_chan *chan)
799 struct ioat_dma_chan *ioat_chan = to_ioat_chan(chan);
800 struct ioatdma_device *ioatdma_device = to_ioatdma_device(chan->device);
801 struct ioat_desc_sw *desc, *_desc;
802 int in_use_descs = 0;
804 /* Before freeing channel resources first check
805 * if they have been previously allocated for this channel.
807 if (ioat_chan->desccount == 0)
808 return;
810 tasklet_disable(&ioat_chan->cleanup_task);
811 ioat_dma_memcpy_cleanup(ioat_chan);
813 /* Delay 100ms after reset to allow internal DMA logic to quiesce
814 * before removing DMA descriptor resources.
816 writeb(IOAT_CHANCMD_RESET,
817 ioat_chan->reg_base
818 + IOAT_CHANCMD_OFFSET(ioat_chan->device->version));
819 mdelay(100);
821 spin_lock_bh(&ioat_chan->desc_lock);
822 switch (ioat_chan->device->version) {
823 case IOAT_VER_1_2:
824 list_for_each_entry_safe(desc, _desc,
825 &ioat_chan->used_desc, node) {
826 in_use_descs++;
827 list_del(&desc->node);
828 pci_pool_free(ioatdma_device->dma_pool, desc->hw,
829 desc->async_tx.phys);
830 kfree(desc);
832 list_for_each_entry_safe(desc, _desc,
833 &ioat_chan->free_desc, node) {
834 list_del(&desc->node);
835 pci_pool_free(ioatdma_device->dma_pool, desc->hw,
836 desc->async_tx.phys);
837 kfree(desc);
839 break;
840 case IOAT_VER_2_0:
841 case IOAT_VER_3_0:
842 list_for_each_entry_safe(desc, _desc,
843 ioat_chan->free_desc.next, node) {
844 list_del(&desc->node);
845 pci_pool_free(ioatdma_device->dma_pool, desc->hw,
846 desc->async_tx.phys);
847 kfree(desc);
849 desc = to_ioat_desc(ioat_chan->free_desc.next);
850 pci_pool_free(ioatdma_device->dma_pool, desc->hw,
851 desc->async_tx.phys);
852 kfree(desc);
853 INIT_LIST_HEAD(&ioat_chan->free_desc);
854 INIT_LIST_HEAD(&ioat_chan->used_desc);
855 break;
857 spin_unlock_bh(&ioat_chan->desc_lock);
859 pci_pool_free(ioatdma_device->completion_pool,
860 ioat_chan->completion_virt,
861 ioat_chan->completion_addr);
863 /* one is ok since we left it on there on purpose */
864 if (in_use_descs > 1)
865 dev_err(&ioat_chan->device->pdev->dev,
866 "Freeing %d in use descriptors!\n",
867 in_use_descs - 1);
869 ioat_chan->last_completion = ioat_chan->completion_addr = 0;
870 ioat_chan->pending = 0;
871 ioat_chan->dmacount = 0;
872 ioat_chan->desccount = 0;
873 ioat_chan->watchdog_completion = 0;
874 ioat_chan->last_compl_desc_addr_hw = 0;
875 ioat_chan->watchdog_tcp_cookie =
876 ioat_chan->watchdog_last_tcp_cookie = 0;
880 * ioat_dma_get_next_descriptor - return the next available descriptor
881 * @ioat_chan: IOAT DMA channel handle
883 * Gets the next descriptor from the chain, and must be called with the
884 * channel's desc_lock held. Allocates more descriptors if the channel
885 * has run out.
887 static struct ioat_desc_sw *
888 ioat1_dma_get_next_descriptor(struct ioat_dma_chan *ioat_chan)
890 struct ioat_desc_sw *new;
892 if (!list_empty(&ioat_chan->free_desc)) {
893 new = to_ioat_desc(ioat_chan->free_desc.next);
894 list_del(&new->node);
895 } else {
896 /* try to get another desc */
897 new = ioat_dma_alloc_descriptor(ioat_chan, GFP_ATOMIC);
898 if (!new) {
899 dev_err(&ioat_chan->device->pdev->dev,
900 "alloc failed\n");
901 return NULL;
905 prefetch(new->hw);
906 return new;
909 static struct ioat_desc_sw *
910 ioat2_dma_get_next_descriptor(struct ioat_dma_chan *ioat_chan)
912 struct ioat_desc_sw *new;
915 * used.prev points to where to start processing
916 * used.next points to next free descriptor
917 * if used.prev == NULL, there are none waiting to be processed
918 * if used.next == used.prev.prev, there is only one free descriptor,
919 * and we need to use it to as a noop descriptor before
920 * linking in a new set of descriptors, since the device
921 * has probably already read the pointer to it
923 if (ioat_chan->used_desc.prev &&
924 ioat_chan->used_desc.next == ioat_chan->used_desc.prev->prev) {
926 struct ioat_desc_sw *desc;
927 struct ioat_desc_sw *noop_desc;
928 int i;
930 /* set up the noop descriptor */
931 noop_desc = to_ioat_desc(ioat_chan->used_desc.next);
932 /* set size to non-zero value (channel returns error when size is 0) */
933 noop_desc->hw->size = NULL_DESC_BUFFER_SIZE;
934 noop_desc->hw->ctl = IOAT_DMA_DESCRIPTOR_NUL;
935 noop_desc->hw->src_addr = 0;
936 noop_desc->hw->dst_addr = 0;
938 ioat_chan->used_desc.next = ioat_chan->used_desc.next->next;
939 ioat_chan->pending++;
940 ioat_chan->dmacount++;
942 /* try to get a few more descriptors */
943 for (i = 16; i; i--) {
944 desc = ioat_dma_alloc_descriptor(ioat_chan, GFP_ATOMIC);
945 if (!desc) {
946 dev_err(&ioat_chan->device->pdev->dev,
947 "alloc failed\n");
948 break;
950 list_add_tail(&desc->node, ioat_chan->used_desc.next);
952 desc->hw->next
953 = to_ioat_desc(desc->node.next)->async_tx.phys;
954 to_ioat_desc(desc->node.prev)->hw->next
955 = desc->async_tx.phys;
956 ioat_chan->desccount++;
959 ioat_chan->used_desc.next = noop_desc->node.next;
961 new = to_ioat_desc(ioat_chan->used_desc.next);
962 prefetch(new);
963 ioat_chan->used_desc.next = new->node.next;
965 if (ioat_chan->used_desc.prev == NULL)
966 ioat_chan->used_desc.prev = &new->node;
968 prefetch(new->hw);
969 return new;
972 static struct ioat_desc_sw *ioat_dma_get_next_descriptor(
973 struct ioat_dma_chan *ioat_chan)
975 if (!ioat_chan)
976 return NULL;
978 switch (ioat_chan->device->version) {
979 case IOAT_VER_1_2:
980 return ioat1_dma_get_next_descriptor(ioat_chan);
981 break;
982 case IOAT_VER_2_0:
983 case IOAT_VER_3_0:
984 return ioat2_dma_get_next_descriptor(ioat_chan);
985 break;
987 return NULL;
990 static struct dma_async_tx_descriptor *ioat1_dma_prep_memcpy(
991 struct dma_chan *chan,
992 dma_addr_t dma_dest,
993 dma_addr_t dma_src,
994 size_t len,
995 unsigned long flags)
997 struct ioat_dma_chan *ioat_chan = to_ioat_chan(chan);
998 struct ioat_desc_sw *new;
1000 spin_lock_bh(&ioat_chan->desc_lock);
1001 new = ioat_dma_get_next_descriptor(ioat_chan);
1002 spin_unlock_bh(&ioat_chan->desc_lock);
1004 if (new) {
1005 new->len = len;
1006 new->dst = dma_dest;
1007 new->src = dma_src;
1008 new->async_tx.flags = flags;
1009 return &new->async_tx;
1010 } else {
1011 dev_err(&ioat_chan->device->pdev->dev,
1012 "chan%d - get_next_desc failed: %d descs waiting, %d total desc\n",
1013 chan_num(ioat_chan), ioat_chan->dmacount, ioat_chan->desccount);
1014 return NULL;
1018 static struct dma_async_tx_descriptor *ioat2_dma_prep_memcpy(
1019 struct dma_chan *chan,
1020 dma_addr_t dma_dest,
1021 dma_addr_t dma_src,
1022 size_t len,
1023 unsigned long flags)
1025 struct ioat_dma_chan *ioat_chan = to_ioat_chan(chan);
1026 struct ioat_desc_sw *new;
1028 spin_lock_bh(&ioat_chan->desc_lock);
1029 new = ioat2_dma_get_next_descriptor(ioat_chan);
1032 * leave ioat_chan->desc_lock set in ioat 2 path
1033 * it will get unlocked at end of tx_submit
1036 if (new) {
1037 new->len = len;
1038 new->dst = dma_dest;
1039 new->src = dma_src;
1040 new->async_tx.flags = flags;
1041 return &new->async_tx;
1042 } else {
1043 spin_unlock_bh(&ioat_chan->desc_lock);
1044 dev_err(&ioat_chan->device->pdev->dev,
1045 "chan%d - get_next_desc failed: %d descs waiting, %d total desc\n",
1046 chan_num(ioat_chan), ioat_chan->dmacount, ioat_chan->desccount);
1047 return NULL;
1051 static void ioat_dma_cleanup_tasklet(unsigned long data)
1053 struct ioat_dma_chan *chan = (void *)data;
1054 ioat_dma_memcpy_cleanup(chan);
1055 writew(IOAT_CHANCTRL_INT_DISABLE,
1056 chan->reg_base + IOAT_CHANCTRL_OFFSET);
1059 static void
1060 ioat_dma_unmap(struct ioat_dma_chan *ioat_chan, struct ioat_desc_sw *desc)
1063 * yes we are unmapping both _page and _single
1064 * alloc'd regions with unmap_page. Is this
1065 * *really* that bad?
1067 if (!(desc->async_tx.flags & DMA_COMPL_SKIP_DEST_UNMAP))
1068 pci_unmap_page(ioat_chan->device->pdev,
1069 pci_unmap_addr(desc, dst),
1070 pci_unmap_len(desc, len),
1071 PCI_DMA_FROMDEVICE);
1073 if (!(desc->async_tx.flags & DMA_COMPL_SKIP_SRC_UNMAP))
1074 pci_unmap_page(ioat_chan->device->pdev,
1075 pci_unmap_addr(desc, src),
1076 pci_unmap_len(desc, len),
1077 PCI_DMA_TODEVICE);
1081 * ioat_dma_memcpy_cleanup - cleanup up finished descriptors
1082 * @chan: ioat channel to be cleaned up
1084 static void ioat_dma_memcpy_cleanup(struct ioat_dma_chan *ioat_chan)
1086 unsigned long phys_complete;
1087 struct ioat_desc_sw *desc, *_desc;
1088 dma_cookie_t cookie = 0;
1089 unsigned long desc_phys;
1090 struct ioat_desc_sw *latest_desc;
1092 prefetch(ioat_chan->completion_virt);
1094 if (!spin_trylock_bh(&ioat_chan->cleanup_lock))
1095 return;
1097 /* The completion writeback can happen at any time,
1098 so reads by the driver need to be atomic operations
1099 The descriptor physical addresses are limited to 32-bits
1100 when the CPU can only do a 32-bit mov */
1102 #if (BITS_PER_LONG == 64)
1103 phys_complete =
1104 ioat_chan->completion_virt->full
1105 & IOAT_CHANSTS_COMPLETED_DESCRIPTOR_ADDR;
1106 #else
1107 phys_complete =
1108 ioat_chan->completion_virt->low & IOAT_LOW_COMPLETION_MASK;
1109 #endif
1111 if ((ioat_chan->completion_virt->full
1112 & IOAT_CHANSTS_DMA_TRANSFER_STATUS) ==
1113 IOAT_CHANSTS_DMA_TRANSFER_STATUS_HALTED) {
1114 dev_err(&ioat_chan->device->pdev->dev,
1115 "Channel halted, chanerr = %x\n",
1116 readl(ioat_chan->reg_base + IOAT_CHANERR_OFFSET));
1118 /* TODO do something to salvage the situation */
1121 if (phys_complete == ioat_chan->last_completion) {
1122 spin_unlock_bh(&ioat_chan->cleanup_lock);
1124 * perhaps we're stuck so hard that the watchdog can't go off?
1125 * try to catch it after 2 seconds
1127 if (ioat_chan->device->version != IOAT_VER_3_0) {
1128 if (time_after(jiffies,
1129 ioat_chan->last_completion_time + HZ*WATCHDOG_DELAY)) {
1130 ioat_dma_chan_watchdog(&(ioat_chan->device->work.work));
1131 ioat_chan->last_completion_time = jiffies;
1134 return;
1136 ioat_chan->last_completion_time = jiffies;
1138 cookie = 0;
1139 if (!spin_trylock_bh(&ioat_chan->desc_lock)) {
1140 spin_unlock_bh(&ioat_chan->cleanup_lock);
1141 return;
1144 switch (ioat_chan->device->version) {
1145 case IOAT_VER_1_2:
1146 list_for_each_entry_safe(desc, _desc,
1147 &ioat_chan->used_desc, node) {
1150 * Incoming DMA requests may use multiple descriptors,
1151 * due to exceeding xfercap, perhaps. If so, only the
1152 * last one will have a cookie, and require unmapping.
1154 if (desc->async_tx.cookie) {
1155 cookie = desc->async_tx.cookie;
1156 ioat_dma_unmap(ioat_chan, desc);
1157 if (desc->async_tx.callback) {
1158 desc->async_tx.callback(desc->async_tx.callback_param);
1159 desc->async_tx.callback = NULL;
1163 if (desc->async_tx.phys != phys_complete) {
1165 * a completed entry, but not the last, so clean
1166 * up if the client is done with the descriptor
1168 if (async_tx_test_ack(&desc->async_tx)) {
1169 list_del(&desc->node);
1170 list_add_tail(&desc->node,
1171 &ioat_chan->free_desc);
1172 } else
1173 desc->async_tx.cookie = 0;
1174 } else {
1176 * last used desc. Do not remove, so we can
1177 * append from it, but don't look at it next
1178 * time, either
1180 desc->async_tx.cookie = 0;
1182 /* TODO check status bits? */
1183 break;
1186 break;
1187 case IOAT_VER_2_0:
1188 case IOAT_VER_3_0:
1189 /* has some other thread has already cleaned up? */
1190 if (ioat_chan->used_desc.prev == NULL)
1191 break;
1193 /* work backwards to find latest finished desc */
1194 desc = to_ioat_desc(ioat_chan->used_desc.next);
1195 latest_desc = NULL;
1196 do {
1197 desc = to_ioat_desc(desc->node.prev);
1198 desc_phys = (unsigned long)desc->async_tx.phys
1199 & IOAT_CHANSTS_COMPLETED_DESCRIPTOR_ADDR;
1200 if (desc_phys == phys_complete) {
1201 latest_desc = desc;
1202 break;
1204 } while (&desc->node != ioat_chan->used_desc.prev);
1206 if (latest_desc != NULL) {
1208 /* work forwards to clear finished descriptors */
1209 for (desc = to_ioat_desc(ioat_chan->used_desc.prev);
1210 &desc->node != latest_desc->node.next &&
1211 &desc->node != ioat_chan->used_desc.next;
1212 desc = to_ioat_desc(desc->node.next)) {
1213 if (desc->async_tx.cookie) {
1214 cookie = desc->async_tx.cookie;
1215 desc->async_tx.cookie = 0;
1216 ioat_dma_unmap(ioat_chan, desc);
1217 if (desc->async_tx.callback) {
1218 desc->async_tx.callback(desc->async_tx.callback_param);
1219 desc->async_tx.callback = NULL;
1224 /* move used.prev up beyond those that are finished */
1225 if (&desc->node == ioat_chan->used_desc.next)
1226 ioat_chan->used_desc.prev = NULL;
1227 else
1228 ioat_chan->used_desc.prev = &desc->node;
1230 break;
1233 spin_unlock_bh(&ioat_chan->desc_lock);
1235 ioat_chan->last_completion = phys_complete;
1236 if (cookie != 0)
1237 ioat_chan->completed_cookie = cookie;
1239 spin_unlock_bh(&ioat_chan->cleanup_lock);
1243 * ioat_dma_is_complete - poll the status of a IOAT DMA transaction
1244 * @chan: IOAT DMA channel handle
1245 * @cookie: DMA transaction identifier
1246 * @done: if not %NULL, updated with last completed transaction
1247 * @used: if not %NULL, updated with last used transaction
1249 static enum dma_status ioat_dma_is_complete(struct dma_chan *chan,
1250 dma_cookie_t cookie,
1251 dma_cookie_t *done,
1252 dma_cookie_t *used)
1254 struct ioat_dma_chan *ioat_chan = to_ioat_chan(chan);
1255 dma_cookie_t last_used;
1256 dma_cookie_t last_complete;
1257 enum dma_status ret;
1259 last_used = chan->cookie;
1260 last_complete = ioat_chan->completed_cookie;
1261 ioat_chan->watchdog_tcp_cookie = cookie;
1263 if (done)
1264 *done = last_complete;
1265 if (used)
1266 *used = last_used;
1268 ret = dma_async_is_complete(cookie, last_complete, last_used);
1269 if (ret == DMA_SUCCESS)
1270 return ret;
1272 ioat_dma_memcpy_cleanup(ioat_chan);
1274 last_used = chan->cookie;
1275 last_complete = ioat_chan->completed_cookie;
1277 if (done)
1278 *done = last_complete;
1279 if (used)
1280 *used = last_used;
1282 return dma_async_is_complete(cookie, last_complete, last_used);
1285 static void ioat_dma_start_null_desc(struct ioat_dma_chan *ioat_chan)
1287 struct ioat_desc_sw *desc;
1289 spin_lock_bh(&ioat_chan->desc_lock);
1291 desc = ioat_dma_get_next_descriptor(ioat_chan);
1293 if (!desc) {
1294 dev_err(&ioat_chan->device->pdev->dev,
1295 "Unable to start null desc - get next desc failed\n");
1296 spin_unlock_bh(&ioat_chan->desc_lock);
1297 return;
1300 desc->hw->ctl = IOAT_DMA_DESCRIPTOR_NUL
1301 | IOAT_DMA_DESCRIPTOR_CTL_INT_GN
1302 | IOAT_DMA_DESCRIPTOR_CTL_CP_STS;
1303 /* set size to non-zero value (channel returns error when size is 0) */
1304 desc->hw->size = NULL_DESC_BUFFER_SIZE;
1305 desc->hw->src_addr = 0;
1306 desc->hw->dst_addr = 0;
1307 async_tx_ack(&desc->async_tx);
1308 switch (ioat_chan->device->version) {
1309 case IOAT_VER_1_2:
1310 desc->hw->next = 0;
1311 list_add_tail(&desc->node, &ioat_chan->used_desc);
1313 writel(((u64) desc->async_tx.phys) & 0x00000000FFFFFFFF,
1314 ioat_chan->reg_base + IOAT1_CHAINADDR_OFFSET_LOW);
1315 writel(((u64) desc->async_tx.phys) >> 32,
1316 ioat_chan->reg_base + IOAT1_CHAINADDR_OFFSET_HIGH);
1318 writeb(IOAT_CHANCMD_START, ioat_chan->reg_base
1319 + IOAT_CHANCMD_OFFSET(ioat_chan->device->version));
1320 break;
1321 case IOAT_VER_2_0:
1322 case IOAT_VER_3_0:
1323 writel(((u64) desc->async_tx.phys) & 0x00000000FFFFFFFF,
1324 ioat_chan->reg_base + IOAT2_CHAINADDR_OFFSET_LOW);
1325 writel(((u64) desc->async_tx.phys) >> 32,
1326 ioat_chan->reg_base + IOAT2_CHAINADDR_OFFSET_HIGH);
1328 ioat_chan->dmacount++;
1329 __ioat2_dma_memcpy_issue_pending(ioat_chan);
1330 break;
1332 spin_unlock_bh(&ioat_chan->desc_lock);
1336 * Perform a IOAT transaction to verify the HW works.
1338 #define IOAT_TEST_SIZE 2000
1340 static void ioat_dma_test_callback(void *dma_async_param)
1342 struct completion *cmp = dma_async_param;
1344 complete(cmp);
1348 * ioat_dma_self_test - Perform a IOAT transaction to verify the HW works.
1349 * @device: device to be tested
1351 static int ioat_dma_self_test(struct ioatdma_device *device)
1353 int i;
1354 u8 *src;
1355 u8 *dest;
1356 struct dma_chan *dma_chan;
1357 struct dma_async_tx_descriptor *tx;
1358 dma_addr_t dma_dest, dma_src;
1359 dma_cookie_t cookie;
1360 int err = 0;
1361 struct completion cmp;
1363 src = kzalloc(sizeof(u8) * IOAT_TEST_SIZE, GFP_KERNEL);
1364 if (!src)
1365 return -ENOMEM;
1366 dest = kzalloc(sizeof(u8) * IOAT_TEST_SIZE, GFP_KERNEL);
1367 if (!dest) {
1368 kfree(src);
1369 return -ENOMEM;
1372 /* Fill in src buffer */
1373 for (i = 0; i < IOAT_TEST_SIZE; i++)
1374 src[i] = (u8)i;
1376 /* Start copy, using first DMA channel */
1377 dma_chan = container_of(device->common.channels.next,
1378 struct dma_chan,
1379 device_node);
1380 if (device->common.device_alloc_chan_resources(dma_chan, NULL) < 1) {
1381 dev_err(&device->pdev->dev,
1382 "selftest cannot allocate chan resource\n");
1383 err = -ENODEV;
1384 goto out;
1387 dma_src = dma_map_single(dma_chan->device->dev, src, IOAT_TEST_SIZE,
1388 DMA_TO_DEVICE);
1389 dma_dest = dma_map_single(dma_chan->device->dev, dest, IOAT_TEST_SIZE,
1390 DMA_FROM_DEVICE);
1391 tx = device->common.device_prep_dma_memcpy(dma_chan, dma_dest, dma_src,
1392 IOAT_TEST_SIZE, 0);
1393 if (!tx) {
1394 dev_err(&device->pdev->dev,
1395 "Self-test prep failed, disabling\n");
1396 err = -ENODEV;
1397 goto free_resources;
1400 async_tx_ack(tx);
1401 init_completion(&cmp);
1402 tx->callback = ioat_dma_test_callback;
1403 tx->callback_param = &cmp;
1404 cookie = tx->tx_submit(tx);
1405 if (cookie < 0) {
1406 dev_err(&device->pdev->dev,
1407 "Self-test setup failed, disabling\n");
1408 err = -ENODEV;
1409 goto free_resources;
1411 device->common.device_issue_pending(dma_chan);
1413 wait_for_completion_timeout(&cmp, msecs_to_jiffies(3000));
1415 if (device->common.device_is_tx_complete(dma_chan, cookie, NULL, NULL)
1416 != DMA_SUCCESS) {
1417 dev_err(&device->pdev->dev,
1418 "Self-test copy timed out, disabling\n");
1419 err = -ENODEV;
1420 goto free_resources;
1422 if (memcmp(src, dest, IOAT_TEST_SIZE)) {
1423 dev_err(&device->pdev->dev,
1424 "Self-test copy failed compare, disabling\n");
1425 err = -ENODEV;
1426 goto free_resources;
1429 free_resources:
1430 device->common.device_free_chan_resources(dma_chan);
1431 out:
1432 kfree(src);
1433 kfree(dest);
1434 return err;
1437 static char ioat_interrupt_style[32] = "msix";
1438 module_param_string(ioat_interrupt_style, ioat_interrupt_style,
1439 sizeof(ioat_interrupt_style), 0644);
1440 MODULE_PARM_DESC(ioat_interrupt_style,
1441 "set ioat interrupt style: msix (default), "
1442 "msix-single-vector, msi, intx)");
1445 * ioat_dma_setup_interrupts - setup interrupt handler
1446 * @device: ioat device
1448 static int ioat_dma_setup_interrupts(struct ioatdma_device *device)
1450 struct ioat_dma_chan *ioat_chan;
1451 int err, i, j, msixcnt;
1452 u8 intrctrl = 0;
1454 if (!strcmp(ioat_interrupt_style, "msix"))
1455 goto msix;
1456 if (!strcmp(ioat_interrupt_style, "msix-single-vector"))
1457 goto msix_single_vector;
1458 if (!strcmp(ioat_interrupt_style, "msi"))
1459 goto msi;
1460 if (!strcmp(ioat_interrupt_style, "intx"))
1461 goto intx;
1462 dev_err(&device->pdev->dev, "invalid ioat_interrupt_style %s\n",
1463 ioat_interrupt_style);
1464 goto err_no_irq;
1466 msix:
1467 /* The number of MSI-X vectors should equal the number of channels */
1468 msixcnt = device->common.chancnt;
1469 for (i = 0; i < msixcnt; i++)
1470 device->msix_entries[i].entry = i;
1472 err = pci_enable_msix(device->pdev, device->msix_entries, msixcnt);
1473 if (err < 0)
1474 goto msi;
1475 if (err > 0)
1476 goto msix_single_vector;
1478 for (i = 0; i < msixcnt; i++) {
1479 ioat_chan = ioat_lookup_chan_by_index(device, i);
1480 err = request_irq(device->msix_entries[i].vector,
1481 ioat_dma_do_interrupt_msix,
1482 0, "ioat-msix", ioat_chan);
1483 if (err) {
1484 for (j = 0; j < i; j++) {
1485 ioat_chan =
1486 ioat_lookup_chan_by_index(device, j);
1487 free_irq(device->msix_entries[j].vector,
1488 ioat_chan);
1490 goto msix_single_vector;
1493 intrctrl |= IOAT_INTRCTRL_MSIX_VECTOR_CONTROL;
1494 device->irq_mode = msix_multi_vector;
1495 goto done;
1497 msix_single_vector:
1498 device->msix_entries[0].entry = 0;
1499 err = pci_enable_msix(device->pdev, device->msix_entries, 1);
1500 if (err)
1501 goto msi;
1503 err = request_irq(device->msix_entries[0].vector, ioat_dma_do_interrupt,
1504 0, "ioat-msix", device);
1505 if (err) {
1506 pci_disable_msix(device->pdev);
1507 goto msi;
1509 device->irq_mode = msix_single_vector;
1510 goto done;
1512 msi:
1513 err = pci_enable_msi(device->pdev);
1514 if (err)
1515 goto intx;
1517 err = request_irq(device->pdev->irq, ioat_dma_do_interrupt,
1518 0, "ioat-msi", device);
1519 if (err) {
1520 pci_disable_msi(device->pdev);
1521 goto intx;
1524 * CB 1.2 devices need a bit set in configuration space to enable MSI
1526 if (device->version == IOAT_VER_1_2) {
1527 u32 dmactrl;
1528 pci_read_config_dword(device->pdev,
1529 IOAT_PCI_DMACTRL_OFFSET, &dmactrl);
1530 dmactrl |= IOAT_PCI_DMACTRL_MSI_EN;
1531 pci_write_config_dword(device->pdev,
1532 IOAT_PCI_DMACTRL_OFFSET, dmactrl);
1534 device->irq_mode = msi;
1535 goto done;
1537 intx:
1538 err = request_irq(device->pdev->irq, ioat_dma_do_interrupt,
1539 IRQF_SHARED, "ioat-intx", device);
1540 if (err)
1541 goto err_no_irq;
1542 device->irq_mode = intx;
1544 done:
1545 intrctrl |= IOAT_INTRCTRL_MASTER_INT_EN;
1546 writeb(intrctrl, device->reg_base + IOAT_INTRCTRL_OFFSET);
1547 return 0;
1549 err_no_irq:
1550 /* Disable all interrupt generation */
1551 writeb(0, device->reg_base + IOAT_INTRCTRL_OFFSET);
1552 dev_err(&device->pdev->dev, "no usable interrupts\n");
1553 device->irq_mode = none;
1554 return -1;
1558 * ioat_dma_remove_interrupts - remove whatever interrupts were set
1559 * @device: ioat device
1561 static void ioat_dma_remove_interrupts(struct ioatdma_device *device)
1563 struct ioat_dma_chan *ioat_chan;
1564 int i;
1566 /* Disable all interrupt generation */
1567 writeb(0, device->reg_base + IOAT_INTRCTRL_OFFSET);
1569 switch (device->irq_mode) {
1570 case msix_multi_vector:
1571 for (i = 0; i < device->common.chancnt; i++) {
1572 ioat_chan = ioat_lookup_chan_by_index(device, i);
1573 free_irq(device->msix_entries[i].vector, ioat_chan);
1575 pci_disable_msix(device->pdev);
1576 break;
1577 case msix_single_vector:
1578 free_irq(device->msix_entries[0].vector, device);
1579 pci_disable_msix(device->pdev);
1580 break;
1581 case msi:
1582 free_irq(device->pdev->irq, device);
1583 pci_disable_msi(device->pdev);
1584 break;
1585 case intx:
1586 free_irq(device->pdev->irq, device);
1587 break;
1588 case none:
1589 dev_warn(&device->pdev->dev,
1590 "call to %s without interrupts setup\n", __func__);
1592 device->irq_mode = none;
1595 struct ioatdma_device *ioat_dma_probe(struct pci_dev *pdev,
1596 void __iomem *iobase)
1598 int err;
1599 struct ioatdma_device *device;
1601 device = kzalloc(sizeof(*device), GFP_KERNEL);
1602 if (!device) {
1603 err = -ENOMEM;
1604 goto err_kzalloc;
1606 device->pdev = pdev;
1607 device->reg_base = iobase;
1608 device->version = readb(device->reg_base + IOAT_VER_OFFSET);
1610 /* DMA coherent memory pool for DMA descriptor allocations */
1611 device->dma_pool = pci_pool_create("dma_desc_pool", pdev,
1612 sizeof(struct ioat_dma_descriptor),
1613 64, 0);
1614 if (!device->dma_pool) {
1615 err = -ENOMEM;
1616 goto err_dma_pool;
1619 device->completion_pool = pci_pool_create("completion_pool", pdev,
1620 sizeof(u64), SMP_CACHE_BYTES,
1621 SMP_CACHE_BYTES);
1622 if (!device->completion_pool) {
1623 err = -ENOMEM;
1624 goto err_completion_pool;
1627 INIT_LIST_HEAD(&device->common.channels);
1628 ioat_dma_enumerate_channels(device);
1630 device->common.device_alloc_chan_resources =
1631 ioat_dma_alloc_chan_resources;
1632 device->common.device_free_chan_resources =
1633 ioat_dma_free_chan_resources;
1634 device->common.dev = &pdev->dev;
1636 dma_cap_set(DMA_MEMCPY, device->common.cap_mask);
1637 device->common.device_is_tx_complete = ioat_dma_is_complete;
1638 switch (device->version) {
1639 case IOAT_VER_1_2:
1640 device->common.device_prep_dma_memcpy = ioat1_dma_prep_memcpy;
1641 device->common.device_issue_pending =
1642 ioat1_dma_memcpy_issue_pending;
1643 break;
1644 case IOAT_VER_2_0:
1645 case IOAT_VER_3_0:
1646 device->common.device_prep_dma_memcpy = ioat2_dma_prep_memcpy;
1647 device->common.device_issue_pending =
1648 ioat2_dma_memcpy_issue_pending;
1649 break;
1652 dev_err(&device->pdev->dev,
1653 "Intel(R) I/OAT DMA Engine found,"
1654 " %d channels, device version 0x%02x, driver version %s\n",
1655 device->common.chancnt, device->version, IOAT_DMA_VERSION);
1657 err = ioat_dma_setup_interrupts(device);
1658 if (err)
1659 goto err_setup_interrupts;
1661 err = ioat_dma_self_test(device);
1662 if (err)
1663 goto err_self_test;
1665 ioat_set_tcp_copy_break(device);
1667 dma_async_device_register(&device->common);
1669 if (device->version != IOAT_VER_3_0) {
1670 INIT_DELAYED_WORK(&device->work, ioat_dma_chan_watchdog);
1671 schedule_delayed_work(&device->work,
1672 WATCHDOG_DELAY);
1675 return device;
1677 err_self_test:
1678 ioat_dma_remove_interrupts(device);
1679 err_setup_interrupts:
1680 pci_pool_destroy(device->completion_pool);
1681 err_completion_pool:
1682 pci_pool_destroy(device->dma_pool);
1683 err_dma_pool:
1684 kfree(device);
1685 err_kzalloc:
1686 dev_err(&pdev->dev,
1687 "Intel(R) I/OAT DMA Engine initialization failed\n");
1688 return NULL;
1691 void ioat_dma_remove(struct ioatdma_device *device)
1693 struct dma_chan *chan, *_chan;
1694 struct ioat_dma_chan *ioat_chan;
1696 ioat_dma_remove_interrupts(device);
1698 dma_async_device_unregister(&device->common);
1700 pci_pool_destroy(device->dma_pool);
1701 pci_pool_destroy(device->completion_pool);
1703 iounmap(device->reg_base);
1704 pci_release_regions(device->pdev);
1705 pci_disable_device(device->pdev);
1707 if (device->version != IOAT_VER_3_0) {
1708 cancel_delayed_work(&device->work);
1711 list_for_each_entry_safe(chan, _chan,
1712 &device->common.channels, device_node) {
1713 ioat_chan = to_ioat_chan(chan);
1714 list_del(&chan->device_node);
1715 kfree(ioat_chan);
1717 kfree(device);