blob: 3995255b16c753731420cb8283992c17c33ddf2e [file] [log] [blame]
Terje Bergstrom65793242013-03-22 16:34:03 +02001/*
2 * Tegra host1x Command DMA
3 *
4 * Copyright (c) 2010-2013, NVIDIA Corporation.
5 *
6 * This program is free software; you can redistribute it and/or modify it
7 * under the terms and conditions of the GNU General Public License,
8 * version 2, as published by the Free Software Foundation.
9 *
10 * This program is distributed in the hope it will be useful, but WITHOUT
11 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
12 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
13 * more details.
14 *
15 * You should have received a copy of the GNU General Public License
16 * along with this program. If not, see <http://www.gnu.org/licenses/>.
17 */
18
19
20#include <asm/cacheflush.h>
21#include <linux/device.h>
22#include <linux/dma-mapping.h>
Thierry Reding35d747a2013-09-24 16:30:32 +020023#include <linux/host1x.h>
Terje Bergstrom65793242013-03-22 16:34:03 +020024#include <linux/interrupt.h>
25#include <linux/kernel.h>
26#include <linux/kfifo.h>
27#include <linux/slab.h>
28#include <trace/events/host1x.h>
29
30#include "cdma.h"
31#include "channel.h"
32#include "dev.h"
33#include "debug.h"
Terje Bergstrom65793242013-03-22 16:34:03 +020034#include "job.h"
35
36/*
37 * push_buffer
38 *
39 * The push buffer is a circular array of words to be fetched by command DMA.
40 * Note that it works slightly differently to the sync queue; fence == pos
41 * means that the push buffer is full, not empty.
42 */
43
44#define HOST1X_PUSHBUFFER_SLOTS 512
45
46/*
47 * Clean up push buffer resources
48 */
49static void host1x_pushbuffer_destroy(struct push_buffer *pb)
50{
51 struct host1x_cdma *cdma = pb_to_cdma(pb);
52 struct host1x *host1x = cdma_to_host1x(cdma);
53
54 if (pb->phys != 0)
55 dma_free_writecombine(host1x->dev, pb->size_bytes + 4,
56 pb->mapped, pb->phys);
57
58 pb->mapped = NULL;
59 pb->phys = 0;
60}
61
62/*
63 * Init push buffer resources
64 */
65static int host1x_pushbuffer_init(struct push_buffer *pb)
66{
67 struct host1x_cdma *cdma = pb_to_cdma(pb);
68 struct host1x *host1x = cdma_to_host1x(cdma);
69
70 pb->mapped = NULL;
71 pb->phys = 0;
72 pb->size_bytes = HOST1X_PUSHBUFFER_SLOTS * 8;
73
74 /* initialize buffer pointers */
75 pb->fence = pb->size_bytes - 8;
76 pb->pos = 0;
77
78 /* allocate and map pushbuffer memory */
79 pb->mapped = dma_alloc_writecombine(host1x->dev, pb->size_bytes + 4,
80 &pb->phys, GFP_KERNEL);
81 if (!pb->mapped)
82 goto fail;
83
84 host1x_hw_pushbuffer_init(host1x, pb);
85
86 return 0;
87
88fail:
89 host1x_pushbuffer_destroy(pb);
90 return -ENOMEM;
91}
92
93/*
94 * Push two words to the push buffer
95 * Caller must ensure push buffer is not full
96 */
97static void host1x_pushbuffer_push(struct push_buffer *pb, u32 op1, u32 op2)
98{
99 u32 pos = pb->pos;
100 u32 *p = (u32 *)((u32)pb->mapped + pos);
101 WARN_ON(pos == pb->fence);
102 *(p++) = op1;
103 *(p++) = op2;
104 pb->pos = (pos + 8) & (pb->size_bytes - 1);
105}
106
107/*
108 * Pop a number of two word slots from the push buffer
109 * Caller must ensure push buffer is not empty
110 */
111static void host1x_pushbuffer_pop(struct push_buffer *pb, unsigned int slots)
112{
113 /* Advance the next write position */
114 pb->fence = (pb->fence + slots * 8) & (pb->size_bytes - 1);
115}
116
117/*
118 * Return the number of two word slots free in the push buffer
119 */
120static u32 host1x_pushbuffer_space(struct push_buffer *pb)
121{
122 return ((pb->fence - pb->pos) & (pb->size_bytes - 1)) / 8;
123}
124
125/*
126 * Sleep (if necessary) until the requested event happens
127 * - CDMA_EVENT_SYNC_QUEUE_EMPTY : sync queue is completely empty.
128 * - Returns 1
129 * - CDMA_EVENT_PUSH_BUFFER_SPACE : there is space in the push buffer
130 * - Return the amount of space (> 0)
131 * Must be called with the cdma lock held.
132 */
133unsigned int host1x_cdma_wait_locked(struct host1x_cdma *cdma,
134 enum cdma_event event)
135{
136 for (;;) {
137 unsigned int space;
138
139 if (event == CDMA_EVENT_SYNC_QUEUE_EMPTY)
140 space = list_empty(&cdma->sync_queue) ? 1 : 0;
141 else if (event == CDMA_EVENT_PUSH_BUFFER_SPACE) {
142 struct push_buffer *pb = &cdma->push_buffer;
143 space = host1x_pushbuffer_space(pb);
144 } else {
145 WARN_ON(1);
146 return -EINVAL;
147 }
148
149 if (space)
150 return space;
151
152 trace_host1x_wait_cdma(dev_name(cdma_to_channel(cdma)->dev),
153 event);
154
155 /* If somebody has managed to already start waiting, yield */
156 if (cdma->event != CDMA_EVENT_NONE) {
157 mutex_unlock(&cdma->lock);
158 schedule();
159 mutex_lock(&cdma->lock);
160 continue;
161 }
162 cdma->event = event;
163
164 mutex_unlock(&cdma->lock);
165 down(&cdma->sem);
166 mutex_lock(&cdma->lock);
167 }
168 return 0;
169}
170
171/*
172 * Start timer that tracks the time spent by the job.
173 * Must be called with the cdma lock held.
174 */
175static void cdma_start_timer_locked(struct host1x_cdma *cdma,
176 struct host1x_job *job)
177{
178 struct host1x *host = cdma_to_host1x(cdma);
179
180 if (cdma->timeout.client) {
181 /* timer already started */
182 return;
183 }
184
185 cdma->timeout.client = job->client;
186 cdma->timeout.syncpt = host1x_syncpt_get(host, job->syncpt_id);
187 cdma->timeout.syncpt_val = job->syncpt_end;
188 cdma->timeout.start_ktime = ktime_get();
189
190 schedule_delayed_work(&cdma->timeout.wq,
191 msecs_to_jiffies(job->timeout));
192}
193
194/*
195 * Stop timer when a buffer submission completes.
196 * Must be called with the cdma lock held.
197 */
198static void stop_cdma_timer_locked(struct host1x_cdma *cdma)
199{
200 cancel_delayed_work(&cdma->timeout.wq);
201 cdma->timeout.client = 0;
202}
203
204/*
205 * For all sync queue entries that have already finished according to the
206 * current sync point registers:
207 * - unpin & unref their mems
208 * - pop their push buffer slots
209 * - remove them from the sync queue
210 * This is normally called from the host code's worker thread, but can be
211 * called manually if necessary.
212 * Must be called with the cdma lock held.
213 */
214static void update_cdma_locked(struct host1x_cdma *cdma)
215{
216 bool signal = false;
217 struct host1x *host1x = cdma_to_host1x(cdma);
218 struct host1x_job *job, *n;
219
220 /* If CDMA is stopped, queue is cleared and we can return */
221 if (!cdma->running)
222 return;
223
224 /*
225 * Walk the sync queue, reading the sync point registers as necessary,
226 * to consume as many sync queue entries as possible without blocking
227 */
228 list_for_each_entry_safe(job, n, &cdma->sync_queue, list) {
229 struct host1x_syncpt *sp =
230 host1x_syncpt_get(host1x, job->syncpt_id);
231
232 /* Check whether this syncpt has completed, and bail if not */
233 if (!host1x_syncpt_is_expired(sp, job->syncpt_end)) {
234 /* Start timer on next pending syncpt */
235 if (job->timeout)
236 cdma_start_timer_locked(cdma, job);
237 break;
238 }
239
240 /* Cancel timeout, when a buffer completes */
241 if (cdma->timeout.client)
242 stop_cdma_timer_locked(cdma);
243
244 /* Unpin the memory */
245 host1x_job_unpin(job);
246
247 /* Pop push buffer slots */
248 if (job->num_slots) {
249 struct push_buffer *pb = &cdma->push_buffer;
250 host1x_pushbuffer_pop(pb, job->num_slots);
251 if (cdma->event == CDMA_EVENT_PUSH_BUFFER_SPACE)
252 signal = true;
253 }
254
255 list_del(&job->list);
256 host1x_job_put(job);
257 }
258
259 if (cdma->event == CDMA_EVENT_SYNC_QUEUE_EMPTY &&
260 list_empty(&cdma->sync_queue))
261 signal = true;
262
263 if (signal) {
264 cdma->event = CDMA_EVENT_NONE;
265 up(&cdma->sem);
266 }
267}
268
269void host1x_cdma_update_sync_queue(struct host1x_cdma *cdma,
270 struct device *dev)
271{
272 u32 restart_addr;
273 u32 syncpt_incrs;
274 struct host1x_job *job = NULL;
275 u32 syncpt_val;
276 struct host1x *host1x = cdma_to_host1x(cdma);
277
278 syncpt_val = host1x_syncpt_load(cdma->timeout.syncpt);
279
280 dev_dbg(dev, "%s: starting cleanup (thresh %d)\n",
281 __func__, syncpt_val);
282
283 /*
284 * Move the sync_queue read pointer to the first entry that hasn't
285 * completed based on the current HW syncpt value. It's likely there
286 * won't be any (i.e. we're still at the head), but covers the case
287 * where a syncpt incr happens just prior/during the teardown.
288 */
289
290 dev_dbg(dev, "%s: skip completed buffers still in sync_queue\n",
291 __func__);
292
293 list_for_each_entry(job, &cdma->sync_queue, list) {
294 if (syncpt_val < job->syncpt_end)
295 break;
296
297 host1x_job_dump(dev, job);
298 }
299
300 /*
301 * Walk the sync_queue, first incrementing with the CPU syncpts that
302 * are partially executed (the first buffer) or fully skipped while
303 * still in the current context (slots are also NOP-ed).
304 *
305 * At the point contexts are interleaved, syncpt increments must be
306 * done inline with the pushbuffer from a GATHER buffer to maintain
307 * the order (slots are modified to be a GATHER of syncpt incrs).
308 *
309 * Note: save in restart_addr the location where the timed out buffer
310 * started in the PB, so we can start the refetch from there (with the
311 * modified NOP-ed PB slots). This lets things appear to have completed
312 * properly for this buffer and resources are freed.
313 */
314
315 dev_dbg(dev, "%s: perform CPU incr on pending same ctx buffers\n",
316 __func__);
317
318 if (!list_empty(&cdma->sync_queue))
319 restart_addr = job->first_get;
320 else
321 restart_addr = cdma->last_pos;
322
323 /* do CPU increments as long as this context continues */
324 list_for_each_entry_from(job, &cdma->sync_queue, list) {
325 /* different context, gets us out of this loop */
326 if (job->client != cdma->timeout.client)
327 break;
328
329 /* won't need a timeout when replayed */
330 job->timeout = 0;
331
332 syncpt_incrs = job->syncpt_end - syncpt_val;
333 dev_dbg(dev, "%s: CPU incr (%d)\n", __func__, syncpt_incrs);
334
335 host1x_job_dump(dev, job);
336
337 /* safe to use CPU to incr syncpts */
338 host1x_hw_cdma_timeout_cpu_incr(host1x, cdma, job->first_get,
339 syncpt_incrs, job->syncpt_end,
340 job->num_slots);
341
342 syncpt_val += syncpt_incrs;
343 }
344
345 /* The following sumbits from the same client may be dependent on the
346 * failed submit and therefore they may fail. Force a small timeout
347 * to make the queue cleanup faster */
348
349 list_for_each_entry_from(job, &cdma->sync_queue, list)
350 if (job->client == cdma->timeout.client)
351 job->timeout = min_t(unsigned int, job->timeout, 500);
352
353 dev_dbg(dev, "%s: finished sync_queue modification\n", __func__);
354
355 /* roll back DMAGET and start up channel again */
356 host1x_hw_cdma_resume(host1x, cdma, restart_addr);
357}
358
359/*
360 * Create a cdma
361 */
362int host1x_cdma_init(struct host1x_cdma *cdma)
363{
364 int err;
365
366 mutex_init(&cdma->lock);
367 sema_init(&cdma->sem, 0);
368
369 INIT_LIST_HEAD(&cdma->sync_queue);
370
371 cdma->event = CDMA_EVENT_NONE;
372 cdma->running = false;
373 cdma->torndown = false;
374
375 err = host1x_pushbuffer_init(&cdma->push_buffer);
376 if (err)
377 return err;
378 return 0;
379}
380
381/*
382 * Destroy a cdma
383 */
384int host1x_cdma_deinit(struct host1x_cdma *cdma)
385{
386 struct push_buffer *pb = &cdma->push_buffer;
387 struct host1x *host1x = cdma_to_host1x(cdma);
388
389 if (cdma->running) {
390 pr_warn("%s: CDMA still running\n", __func__);
391 return -EBUSY;
392 }
393
394 host1x_pushbuffer_destroy(pb);
395 host1x_hw_cdma_timeout_destroy(host1x, cdma);
396
397 return 0;
398}
399
400/*
401 * Begin a cdma submit
402 */
403int host1x_cdma_begin(struct host1x_cdma *cdma, struct host1x_job *job)
404{
405 struct host1x *host1x = cdma_to_host1x(cdma);
406
407 mutex_lock(&cdma->lock);
408
409 if (job->timeout) {
410 /* init state on first submit with timeout value */
411 if (!cdma->timeout.initialized) {
412 int err;
413 err = host1x_hw_cdma_timeout_init(host1x, cdma,
414 job->syncpt_id);
415 if (err) {
416 mutex_unlock(&cdma->lock);
417 return err;
418 }
419 }
420 }
421 if (!cdma->running)
422 host1x_hw_cdma_start(host1x, cdma);
423
424 cdma->slots_free = 0;
425 cdma->slots_used = 0;
426 cdma->first_get = cdma->push_buffer.pos;
427
428 trace_host1x_cdma_begin(dev_name(job->channel->dev));
429 return 0;
430}
431
432/*
433 * Push two words into a push buffer slot
434 * Blocks as necessary if the push buffer is full.
435 */
436void host1x_cdma_push(struct host1x_cdma *cdma, u32 op1, u32 op2)
437{
438 struct host1x *host1x = cdma_to_host1x(cdma);
439 struct push_buffer *pb = &cdma->push_buffer;
440 u32 slots_free = cdma->slots_free;
441
Terje Bergstrom62364512013-03-22 16:34:04 +0200442 if (host1x_debug_trace_cmdbuf)
443 trace_host1x_cdma_push(dev_name(cdma_to_channel(cdma)->dev),
444 op1, op2);
445
Terje Bergstrom65793242013-03-22 16:34:03 +0200446 if (slots_free == 0) {
447 host1x_hw_cdma_flush(host1x, cdma);
448 slots_free = host1x_cdma_wait_locked(cdma,
449 CDMA_EVENT_PUSH_BUFFER_SPACE);
450 }
451 cdma->slots_free = slots_free - 1;
452 cdma->slots_used++;
453 host1x_pushbuffer_push(pb, op1, op2);
454}
455
456/*
457 * End a cdma submit
458 * Kick off DMA, add job to the sync queue, and a number of slots to be freed
459 * from the pushbuffer. The handles for a submit must all be pinned at the same
460 * time, but they can be unpinned in smaller chunks.
461 */
462void host1x_cdma_end(struct host1x_cdma *cdma,
463 struct host1x_job *job)
464{
465 struct host1x *host1x = cdma_to_host1x(cdma);
466 bool idle = list_empty(&cdma->sync_queue);
467
468 host1x_hw_cdma_flush(host1x, cdma);
469
470 job->first_get = cdma->first_get;
471 job->num_slots = cdma->slots_used;
472 host1x_job_get(job);
473 list_add_tail(&job->list, &cdma->sync_queue);
474
475 /* start timer on idle -> active transitions */
476 if (job->timeout && idle)
477 cdma_start_timer_locked(cdma, job);
478
479 trace_host1x_cdma_end(dev_name(job->channel->dev));
480 mutex_unlock(&cdma->lock);
481}
482
483/*
484 * Update cdma state according to current sync point values
485 */
486void host1x_cdma_update(struct host1x_cdma *cdma)
487{
488 mutex_lock(&cdma->lock);
489 update_cdma_locked(cdma);
490 mutex_unlock(&cdma->lock);
491}