2 * Tegra host1x Command DMA
4 * Copyright (c) 2010-2013, NVIDIA Corporation.
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.
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
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/>.
20 #include <asm/cacheflush.h>
21 #include <linux/device.h>
22 #include <linux/dma-mapping.h>
23 #include <linux/host1x.h>
24 #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>
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.
44 #define HOST1X_PUSHBUFFER_SLOTS 512
47 * Clean up push buffer resources
49 static void host1x_pushbuffer_destroy(struct push_buffer
*pb
)
51 struct host1x_cdma
*cdma
= pb_to_cdma(pb
);
52 struct host1x
*host1x
= cdma_to_host1x(cdma
);
55 dma_free_wc(host1x
->dev
, pb
->size_bytes
+ 4, pb
->mapped
,
63 * Init push buffer resources
65 static int host1x_pushbuffer_init(struct push_buffer
*pb
)
67 struct host1x_cdma
*cdma
= pb_to_cdma(pb
);
68 struct host1x
*host1x
= cdma_to_host1x(cdma
);
72 pb
->size_bytes
= HOST1X_PUSHBUFFER_SLOTS
* 8;
74 /* initialize buffer pointers */
75 pb
->fence
= pb
->size_bytes
- 8;
78 /* allocate and map pushbuffer memory */
79 pb
->mapped
= dma_alloc_wc(host1x
->dev
, pb
->size_bytes
+ 4, &pb
->phys
,
84 host1x_hw_pushbuffer_init(host1x
, pb
);
89 host1x_pushbuffer_destroy(pb
);
94 * Push two words to the push buffer
95 * Caller must ensure push buffer is not full
97 static void host1x_pushbuffer_push(struct push_buffer
*pb
, u32 op1
, u32 op2
)
99 u32
*p
= (u32
*)((void *)pb
->mapped
+ pb
->pos
);
101 WARN_ON(pb
->pos
== pb
->fence
);
104 pb
->pos
= (pb
->pos
+ 8) & (pb
->size_bytes
- 1);
108 * Pop a number of two word slots from the push buffer
109 * Caller must ensure push buffer is not empty
111 static void host1x_pushbuffer_pop(struct push_buffer
*pb
, unsigned int slots
)
113 /* Advance the next write position */
114 pb
->fence
= (pb
->fence
+ slots
* 8) & (pb
->size_bytes
- 1);
118 * Return the number of two word slots free in the push buffer
120 static u32
host1x_pushbuffer_space(struct push_buffer
*pb
)
122 return ((pb
->fence
- pb
->pos
) & (pb
->size_bytes
- 1)) / 8;
126 * Sleep (if necessary) until the requested event happens
127 * - CDMA_EVENT_SYNC_QUEUE_EMPTY : sync queue is completely empty.
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.
133 unsigned int host1x_cdma_wait_locked(struct host1x_cdma
*cdma
,
134 enum cdma_event event
)
137 struct push_buffer
*pb
= &cdma
->push_buffer
;
141 case CDMA_EVENT_SYNC_QUEUE_EMPTY
:
142 space
= list_empty(&cdma
->sync_queue
) ? 1 : 0;
145 case CDMA_EVENT_PUSH_BUFFER_SPACE
:
146 space
= host1x_pushbuffer_space(pb
);
157 trace_host1x_wait_cdma(dev_name(cdma_to_channel(cdma
)->dev
),
160 /* If somebody has managed to already start waiting, yield */
161 if (cdma
->event
!= CDMA_EVENT_NONE
) {
162 mutex_unlock(&cdma
->lock
);
164 mutex_lock(&cdma
->lock
);
170 mutex_unlock(&cdma
->lock
);
172 mutex_lock(&cdma
->lock
);
179 * Start timer that tracks the time spent by the job.
180 * Must be called with the cdma lock held.
182 static void cdma_start_timer_locked(struct host1x_cdma
*cdma
,
183 struct host1x_job
*job
)
185 struct host1x
*host
= cdma_to_host1x(cdma
);
187 if (cdma
->timeout
.client
) {
188 /* timer already started */
192 cdma
->timeout
.client
= job
->client
;
193 cdma
->timeout
.syncpt
= host1x_syncpt_get(host
, job
->syncpt_id
);
194 cdma
->timeout
.syncpt_val
= job
->syncpt_end
;
195 cdma
->timeout
.start_ktime
= ktime_get();
197 schedule_delayed_work(&cdma
->timeout
.wq
,
198 msecs_to_jiffies(job
->timeout
));
202 * Stop timer when a buffer submission completes.
203 * Must be called with the cdma lock held.
205 static void stop_cdma_timer_locked(struct host1x_cdma
*cdma
)
207 cancel_delayed_work(&cdma
->timeout
.wq
);
208 cdma
->timeout
.client
= 0;
212 * For all sync queue entries that have already finished according to the
213 * current sync point registers:
214 * - unpin & unref their mems
215 * - pop their push buffer slots
216 * - remove them from the sync queue
217 * This is normally called from the host code's worker thread, but can be
218 * called manually if necessary.
219 * Must be called with the cdma lock held.
221 static void update_cdma_locked(struct host1x_cdma
*cdma
)
224 struct host1x
*host1x
= cdma_to_host1x(cdma
);
225 struct host1x_job
*job
, *n
;
227 /* If CDMA is stopped, queue is cleared and we can return */
232 * Walk the sync queue, reading the sync point registers as necessary,
233 * to consume as many sync queue entries as possible without blocking
235 list_for_each_entry_safe(job
, n
, &cdma
->sync_queue
, list
) {
236 struct host1x_syncpt
*sp
=
237 host1x_syncpt_get(host1x
, job
->syncpt_id
);
239 /* Check whether this syncpt has completed, and bail if not */
240 if (!host1x_syncpt_is_expired(sp
, job
->syncpt_end
)) {
241 /* Start timer on next pending syncpt */
243 cdma_start_timer_locked(cdma
, job
);
248 /* Cancel timeout, when a buffer completes */
249 if (cdma
->timeout
.client
)
250 stop_cdma_timer_locked(cdma
);
252 /* Unpin the memory */
253 host1x_job_unpin(job
);
255 /* Pop push buffer slots */
256 if (job
->num_slots
) {
257 struct push_buffer
*pb
= &cdma
->push_buffer
;
259 host1x_pushbuffer_pop(pb
, job
->num_slots
);
261 if (cdma
->event
== CDMA_EVENT_PUSH_BUFFER_SPACE
)
265 list_del(&job
->list
);
269 if (cdma
->event
== CDMA_EVENT_SYNC_QUEUE_EMPTY
&&
270 list_empty(&cdma
->sync_queue
))
274 cdma
->event
= CDMA_EVENT_NONE
;
279 void host1x_cdma_update_sync_queue(struct host1x_cdma
*cdma
,
282 struct host1x
*host1x
= cdma_to_host1x(cdma
);
283 u32 restart_addr
, syncpt_incrs
, syncpt_val
;
284 struct host1x_job
*job
= NULL
;
286 syncpt_val
= host1x_syncpt_load(cdma
->timeout
.syncpt
);
288 dev_dbg(dev
, "%s: starting cleanup (thresh %d)\n",
289 __func__
, syncpt_val
);
292 * Move the sync_queue read pointer to the first entry that hasn't
293 * completed based on the current HW syncpt value. It's likely there
294 * won't be any (i.e. we're still at the head), but covers the case
295 * where a syncpt incr happens just prior/during the teardown.
298 dev_dbg(dev
, "%s: skip completed buffers still in sync_queue\n",
301 list_for_each_entry(job
, &cdma
->sync_queue
, list
) {
302 if (syncpt_val
< job
->syncpt_end
)
305 host1x_job_dump(dev
, job
);
309 * Walk the sync_queue, first incrementing with the CPU syncpts that
310 * are partially executed (the first buffer) or fully skipped while
311 * still in the current context (slots are also NOP-ed).
313 * At the point contexts are interleaved, syncpt increments must be
314 * done inline with the pushbuffer from a GATHER buffer to maintain
315 * the order (slots are modified to be a GATHER of syncpt incrs).
317 * Note: save in restart_addr the location where the timed out buffer
318 * started in the PB, so we can start the refetch from there (with the
319 * modified NOP-ed PB slots). This lets things appear to have completed
320 * properly for this buffer and resources are freed.
323 dev_dbg(dev
, "%s: perform CPU incr on pending same ctx buffers\n",
326 if (!list_empty(&cdma
->sync_queue
))
327 restart_addr
= job
->first_get
;
329 restart_addr
= cdma
->last_pos
;
331 /* do CPU increments as long as this context continues */
332 list_for_each_entry_from(job
, &cdma
->sync_queue
, list
) {
333 /* different context, gets us out of this loop */
334 if (job
->client
!= cdma
->timeout
.client
)
337 /* won't need a timeout when replayed */
340 syncpt_incrs
= job
->syncpt_end
- syncpt_val
;
341 dev_dbg(dev
, "%s: CPU incr (%d)\n", __func__
, syncpt_incrs
);
343 host1x_job_dump(dev
, job
);
345 /* safe to use CPU to incr syncpts */
346 host1x_hw_cdma_timeout_cpu_incr(host1x
, cdma
, job
->first_get
,
347 syncpt_incrs
, job
->syncpt_end
,
350 syncpt_val
+= syncpt_incrs
;
354 * The following sumbits from the same client may be dependent on the
355 * failed submit and therefore they may fail. Force a small timeout
356 * to make the queue cleanup faster.
359 list_for_each_entry_from(job
, &cdma
->sync_queue
, list
)
360 if (job
->client
== cdma
->timeout
.client
)
361 job
->timeout
= min_t(unsigned int, job
->timeout
, 500);
363 dev_dbg(dev
, "%s: finished sync_queue modification\n", __func__
);
365 /* roll back DMAGET and start up channel again */
366 host1x_hw_cdma_resume(host1x
, cdma
, restart_addr
);
372 int host1x_cdma_init(struct host1x_cdma
*cdma
)
376 mutex_init(&cdma
->lock
);
377 sema_init(&cdma
->sem
, 0);
379 INIT_LIST_HEAD(&cdma
->sync_queue
);
381 cdma
->event
= CDMA_EVENT_NONE
;
382 cdma
->running
= false;
383 cdma
->torndown
= false;
385 err
= host1x_pushbuffer_init(&cdma
->push_buffer
);
395 int host1x_cdma_deinit(struct host1x_cdma
*cdma
)
397 struct push_buffer
*pb
= &cdma
->push_buffer
;
398 struct host1x
*host1x
= cdma_to_host1x(cdma
);
401 pr_warn("%s: CDMA still running\n", __func__
);
405 host1x_pushbuffer_destroy(pb
);
406 host1x_hw_cdma_timeout_destroy(host1x
, cdma
);
412 * Begin a cdma submit
414 int host1x_cdma_begin(struct host1x_cdma
*cdma
, struct host1x_job
*job
)
416 struct host1x
*host1x
= cdma_to_host1x(cdma
);
418 mutex_lock(&cdma
->lock
);
421 /* init state on first submit with timeout value */
422 if (!cdma
->timeout
.initialized
) {
425 err
= host1x_hw_cdma_timeout_init(host1x
, cdma
,
428 mutex_unlock(&cdma
->lock
);
435 host1x_hw_cdma_start(host1x
, cdma
);
437 cdma
->slots_free
= 0;
438 cdma
->slots_used
= 0;
439 cdma
->first_get
= cdma
->push_buffer
.pos
;
441 trace_host1x_cdma_begin(dev_name(job
->channel
->dev
));
446 * Push two words into a push buffer slot
447 * Blocks as necessary if the push buffer is full.
449 void host1x_cdma_push(struct host1x_cdma
*cdma
, u32 op1
, u32 op2
)
451 struct host1x
*host1x
= cdma_to_host1x(cdma
);
452 struct push_buffer
*pb
= &cdma
->push_buffer
;
453 u32 slots_free
= cdma
->slots_free
;
455 if (host1x_debug_trace_cmdbuf
)
456 trace_host1x_cdma_push(dev_name(cdma_to_channel(cdma
)->dev
),
459 if (slots_free
== 0) {
460 host1x_hw_cdma_flush(host1x
, cdma
);
461 slots_free
= host1x_cdma_wait_locked(cdma
,
462 CDMA_EVENT_PUSH_BUFFER_SPACE
);
465 cdma
->slots_free
= slots_free
- 1;
467 host1x_pushbuffer_push(pb
, op1
, op2
);
472 * Kick off DMA, add job to the sync queue, and a number of slots to be freed
473 * from the pushbuffer. The handles for a submit must all be pinned at the same
474 * time, but they can be unpinned in smaller chunks.
476 void host1x_cdma_end(struct host1x_cdma
*cdma
,
477 struct host1x_job
*job
)
479 struct host1x
*host1x
= cdma_to_host1x(cdma
);
480 bool idle
= list_empty(&cdma
->sync_queue
);
482 host1x_hw_cdma_flush(host1x
, cdma
);
484 job
->first_get
= cdma
->first_get
;
485 job
->num_slots
= cdma
->slots_used
;
487 list_add_tail(&job
->list
, &cdma
->sync_queue
);
489 /* start timer on idle -> active transitions */
490 if (job
->timeout
&& idle
)
491 cdma_start_timer_locked(cdma
, job
);
493 trace_host1x_cdma_end(dev_name(job
->channel
->dev
));
494 mutex_unlock(&cdma
->lock
);
498 * Update cdma state according to current sync point values
500 void host1x_cdma_update(struct host1x_cdma
*cdma
)
502 mutex_lock(&cdma
->lock
);
503 update_cdma_locked(cdma
);
504 mutex_unlock(&cdma
->lock
);