xref: /openbmc/linux/drivers/gpu/drm/radeon/radeon_fence.c (revision baa7eb025ab14f3cba2e35c0a8648f9c9f01d24f)
1 /*
2  * Copyright 2009 Jerome Glisse.
3  * All Rights Reserved.
4  *
5  * Permission is hereby granted, free of charge, to any person obtaining a
6  * copy of this software and associated documentation files (the
7  * "Software"), to deal in the Software without restriction, including
8  * without limitation the rights to use, copy, modify, merge, publish,
9  * distribute, sub license, and/or sell copies of the Software, and to
10  * permit persons to whom the Software is furnished to do so, subject to
11  * the following conditions:
12  *
13  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
14  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
15  * FITNESS FOR A PARTICULAR PURPOSE AND NON-INFRINGEMENT. IN NO EVENT SHALL
16  * THE COPYRIGHT HOLDERS, AUTHORS AND/OR ITS SUPPLIERS BE LIABLE FOR ANY CLAIM,
17  * DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR
18  * OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE
19  * USE OR OTHER DEALINGS IN THE SOFTWARE.
20  *
21  * The above copyright notice and this permission notice (including the
22  * next paragraph) shall be included in all copies or substantial portions
23  * of the Software.
24  *
25  */
26 /*
27  * Authors:
28  *    Jerome Glisse <glisse@freedesktop.org>
29  *    Dave Airlie
30  */
31 #include <linux/seq_file.h>
32 #include <asm/atomic.h>
33 #include <linux/wait.h>
34 #include <linux/list.h>
35 #include <linux/kref.h>
36 #include <linux/slab.h>
37 #include "drmP.h"
38 #include "drm.h"
39 #include "radeon_reg.h"
40 #include "radeon.h"
41 
42 int radeon_fence_emit(struct radeon_device *rdev, struct radeon_fence *fence)
43 {
44 	unsigned long irq_flags;
45 
46 	write_lock_irqsave(&rdev->fence_drv.lock, irq_flags);
47 	if (fence->emited) {
48 		write_unlock_irqrestore(&rdev->fence_drv.lock, irq_flags);
49 		return 0;
50 	}
51 	fence->seq = atomic_add_return(1, &rdev->fence_drv.seq);
52 	if (!rdev->cp.ready) {
53 		/* FIXME: cp is not running assume everythings is done right
54 		 * away
55 		 */
56 		WREG32(rdev->fence_drv.scratch_reg, fence->seq);
57 	} else
58 		radeon_fence_ring_emit(rdev, fence);
59 
60 	fence->emited = true;
61 	list_del(&fence->list);
62 	list_add_tail(&fence->list, &rdev->fence_drv.emited);
63 	write_unlock_irqrestore(&rdev->fence_drv.lock, irq_flags);
64 	return 0;
65 }
66 
67 static bool radeon_fence_poll_locked(struct radeon_device *rdev)
68 {
69 	struct radeon_fence *fence;
70 	struct list_head *i, *n;
71 	uint32_t seq;
72 	bool wake = false;
73 	unsigned long cjiffies;
74 
75 	if (rdev->wb.enabled) {
76 		u32 scratch_index;
77 		if (rdev->wb.use_event)
78 			scratch_index = R600_WB_EVENT_OFFSET + rdev->fence_drv.scratch_reg - rdev->scratch.reg_base;
79 		else
80 			scratch_index = RADEON_WB_SCRATCH_OFFSET + rdev->fence_drv.scratch_reg - rdev->scratch.reg_base;
81 		seq = rdev->wb.wb[scratch_index/4];
82 	} else
83 		seq = RREG32(rdev->fence_drv.scratch_reg);
84 	if (seq != rdev->fence_drv.last_seq) {
85 		rdev->fence_drv.last_seq = seq;
86 		rdev->fence_drv.last_jiffies = jiffies;
87 		rdev->fence_drv.last_timeout = RADEON_FENCE_JIFFIES_TIMEOUT;
88 	} else {
89 		cjiffies = jiffies;
90 		if (time_after(cjiffies, rdev->fence_drv.last_jiffies)) {
91 			cjiffies -= rdev->fence_drv.last_jiffies;
92 			if (time_after(rdev->fence_drv.last_timeout, cjiffies)) {
93 				/* update the timeout */
94 				rdev->fence_drv.last_timeout -= cjiffies;
95 			} else {
96 				/* the 500ms timeout is elapsed we should test
97 				 * for GPU lockup
98 				 */
99 				rdev->fence_drv.last_timeout = 1;
100 			}
101 		} else {
102 			/* wrap around update last jiffies, we will just wait
103 			 * a little longer
104 			 */
105 			rdev->fence_drv.last_jiffies = cjiffies;
106 		}
107 		return false;
108 	}
109 	n = NULL;
110 	list_for_each(i, &rdev->fence_drv.emited) {
111 		fence = list_entry(i, struct radeon_fence, list);
112 		if (fence->seq == seq) {
113 			n = i;
114 			break;
115 		}
116 	}
117 	/* all fence previous to this one are considered as signaled */
118 	if (n) {
119 		i = n;
120 		do {
121 			n = i->prev;
122 			list_del(i);
123 			list_add_tail(i, &rdev->fence_drv.signaled);
124 			fence = list_entry(i, struct radeon_fence, list);
125 			fence->signaled = true;
126 			i = n;
127 		} while (i != &rdev->fence_drv.emited);
128 		wake = true;
129 	}
130 	return wake;
131 }
132 
133 static void radeon_fence_destroy(struct kref *kref)
134 {
135 	unsigned long irq_flags;
136         struct radeon_fence *fence;
137 
138 	fence = container_of(kref, struct radeon_fence, kref);
139 	write_lock_irqsave(&fence->rdev->fence_drv.lock, irq_flags);
140 	list_del(&fence->list);
141 	fence->emited = false;
142 	write_unlock_irqrestore(&fence->rdev->fence_drv.lock, irq_flags);
143 	kfree(fence);
144 }
145 
146 int radeon_fence_create(struct radeon_device *rdev, struct radeon_fence **fence)
147 {
148 	unsigned long irq_flags;
149 
150 	*fence = kmalloc(sizeof(struct radeon_fence), GFP_KERNEL);
151 	if ((*fence) == NULL) {
152 		return -ENOMEM;
153 	}
154 	kref_init(&((*fence)->kref));
155 	(*fence)->rdev = rdev;
156 	(*fence)->emited = false;
157 	(*fence)->signaled = false;
158 	(*fence)->seq = 0;
159 	INIT_LIST_HEAD(&(*fence)->list);
160 
161 	write_lock_irqsave(&rdev->fence_drv.lock, irq_flags);
162 	list_add_tail(&(*fence)->list, &rdev->fence_drv.created);
163 	write_unlock_irqrestore(&rdev->fence_drv.lock, irq_flags);
164 	return 0;
165 }
166 
167 
168 bool radeon_fence_signaled(struct radeon_fence *fence)
169 {
170 	unsigned long irq_flags;
171 	bool signaled = false;
172 
173 	if (!fence)
174 		return true;
175 
176 	if (fence->rdev->gpu_lockup)
177 		return true;
178 
179 	write_lock_irqsave(&fence->rdev->fence_drv.lock, irq_flags);
180 	signaled = fence->signaled;
181 	/* if we are shuting down report all fence as signaled */
182 	if (fence->rdev->shutdown) {
183 		signaled = true;
184 	}
185 	if (!fence->emited) {
186 		WARN(1, "Querying an unemited fence : %p !\n", fence);
187 		signaled = true;
188 	}
189 	if (!signaled) {
190 		radeon_fence_poll_locked(fence->rdev);
191 		signaled = fence->signaled;
192 	}
193 	write_unlock_irqrestore(&fence->rdev->fence_drv.lock, irq_flags);
194 	return signaled;
195 }
196 
197 int radeon_fence_wait(struct radeon_fence *fence, bool intr)
198 {
199 	struct radeon_device *rdev;
200 	unsigned long irq_flags, timeout;
201 	u32 seq;
202 	int r;
203 
204 	if (fence == NULL) {
205 		WARN(1, "Querying an invalid fence : %p !\n", fence);
206 		return 0;
207 	}
208 	rdev = fence->rdev;
209 	if (radeon_fence_signaled(fence)) {
210 		return 0;
211 	}
212 	timeout = rdev->fence_drv.last_timeout;
213 retry:
214 	/* save current sequence used to check for GPU lockup */
215 	seq = rdev->fence_drv.last_seq;
216 	if (intr) {
217 		radeon_irq_kms_sw_irq_get(rdev);
218 		r = wait_event_interruptible_timeout(rdev->fence_drv.queue,
219 				radeon_fence_signaled(fence), timeout);
220 		radeon_irq_kms_sw_irq_put(rdev);
221 		if (unlikely(r < 0)) {
222 			return r;
223 		}
224 	} else {
225 		radeon_irq_kms_sw_irq_get(rdev);
226 		r = wait_event_timeout(rdev->fence_drv.queue,
227 			 radeon_fence_signaled(fence), timeout);
228 		radeon_irq_kms_sw_irq_put(rdev);
229 	}
230 	if (unlikely(!radeon_fence_signaled(fence))) {
231 		/* we were interrupted for some reason and fence isn't
232 		 * isn't signaled yet, resume wait
233 		 */
234 		if (r) {
235 			timeout = r;
236 			goto retry;
237 		}
238 		/* don't protect read access to rdev->fence_drv.last_seq
239 		 * if we experiencing a lockup the value doesn't change
240 		 */
241 		if (seq == rdev->fence_drv.last_seq && radeon_gpu_is_lockup(rdev)) {
242 			/* good news we believe it's a lockup */
243 			WARN(1, "GPU lockup (waiting for 0x%08X last fence id 0x%08X)\n",
244 			     fence->seq, seq);
245 			/* FIXME: what should we do ? marking everyone
246 			 * as signaled for now
247 			 */
248 			rdev->gpu_lockup = true;
249 			r = radeon_gpu_reset(rdev);
250 			if (r)
251 				return r;
252 			WREG32(rdev->fence_drv.scratch_reg, fence->seq);
253 			rdev->gpu_lockup = false;
254 		}
255 		timeout = RADEON_FENCE_JIFFIES_TIMEOUT;
256 		write_lock_irqsave(&rdev->fence_drv.lock, irq_flags);
257 		rdev->fence_drv.last_timeout = RADEON_FENCE_JIFFIES_TIMEOUT;
258 		rdev->fence_drv.last_jiffies = jiffies;
259 		write_unlock_irqrestore(&rdev->fence_drv.lock, irq_flags);
260 		goto retry;
261 	}
262 	return 0;
263 }
264 
265 int radeon_fence_wait_next(struct radeon_device *rdev)
266 {
267 	unsigned long irq_flags;
268 	struct radeon_fence *fence;
269 	int r;
270 
271 	if (rdev->gpu_lockup) {
272 		return 0;
273 	}
274 	write_lock_irqsave(&rdev->fence_drv.lock, irq_flags);
275 	if (list_empty(&rdev->fence_drv.emited)) {
276 		write_unlock_irqrestore(&rdev->fence_drv.lock, irq_flags);
277 		return 0;
278 	}
279 	fence = list_entry(rdev->fence_drv.emited.next,
280 			   struct radeon_fence, list);
281 	radeon_fence_ref(fence);
282 	write_unlock_irqrestore(&rdev->fence_drv.lock, irq_flags);
283 	r = radeon_fence_wait(fence, false);
284 	radeon_fence_unref(&fence);
285 	return r;
286 }
287 
288 int radeon_fence_wait_last(struct radeon_device *rdev)
289 {
290 	unsigned long irq_flags;
291 	struct radeon_fence *fence;
292 	int r;
293 
294 	if (rdev->gpu_lockup) {
295 		return 0;
296 	}
297 	write_lock_irqsave(&rdev->fence_drv.lock, irq_flags);
298 	if (list_empty(&rdev->fence_drv.emited)) {
299 		write_unlock_irqrestore(&rdev->fence_drv.lock, irq_flags);
300 		return 0;
301 	}
302 	fence = list_entry(rdev->fence_drv.emited.prev,
303 			   struct radeon_fence, list);
304 	radeon_fence_ref(fence);
305 	write_unlock_irqrestore(&rdev->fence_drv.lock, irq_flags);
306 	r = radeon_fence_wait(fence, false);
307 	radeon_fence_unref(&fence);
308 	return r;
309 }
310 
311 struct radeon_fence *radeon_fence_ref(struct radeon_fence *fence)
312 {
313 	kref_get(&fence->kref);
314 	return fence;
315 }
316 
317 void radeon_fence_unref(struct radeon_fence **fence)
318 {
319 	struct radeon_fence *tmp = *fence;
320 
321 	*fence = NULL;
322 	if (tmp) {
323 		kref_put(&tmp->kref, &radeon_fence_destroy);
324 	}
325 }
326 
327 void radeon_fence_process(struct radeon_device *rdev)
328 {
329 	unsigned long irq_flags;
330 	bool wake;
331 
332 	write_lock_irqsave(&rdev->fence_drv.lock, irq_flags);
333 	wake = radeon_fence_poll_locked(rdev);
334 	write_unlock_irqrestore(&rdev->fence_drv.lock, irq_flags);
335 	if (wake) {
336 		wake_up_all(&rdev->fence_drv.queue);
337 	}
338 }
339 
340 int radeon_fence_driver_init(struct radeon_device *rdev)
341 {
342 	unsigned long irq_flags;
343 	int r;
344 
345 	write_lock_irqsave(&rdev->fence_drv.lock, irq_flags);
346 	r = radeon_scratch_get(rdev, &rdev->fence_drv.scratch_reg);
347 	if (r) {
348 		dev_err(rdev->dev, "fence failed to get scratch register\n");
349 		write_unlock_irqrestore(&rdev->fence_drv.lock, irq_flags);
350 		return r;
351 	}
352 	WREG32(rdev->fence_drv.scratch_reg, 0);
353 	atomic_set(&rdev->fence_drv.seq, 0);
354 	INIT_LIST_HEAD(&rdev->fence_drv.created);
355 	INIT_LIST_HEAD(&rdev->fence_drv.emited);
356 	INIT_LIST_HEAD(&rdev->fence_drv.signaled);
357 	init_waitqueue_head(&rdev->fence_drv.queue);
358 	rdev->fence_drv.initialized = true;
359 	write_unlock_irqrestore(&rdev->fence_drv.lock, irq_flags);
360 	if (radeon_debugfs_fence_init(rdev)) {
361 		dev_err(rdev->dev, "fence debugfs file creation failed\n");
362 	}
363 	return 0;
364 }
365 
366 void radeon_fence_driver_fini(struct radeon_device *rdev)
367 {
368 	unsigned long irq_flags;
369 
370 	if (!rdev->fence_drv.initialized)
371 		return;
372 	wake_up_all(&rdev->fence_drv.queue);
373 	write_lock_irqsave(&rdev->fence_drv.lock, irq_flags);
374 	radeon_scratch_free(rdev, rdev->fence_drv.scratch_reg);
375 	write_unlock_irqrestore(&rdev->fence_drv.lock, irq_flags);
376 	rdev->fence_drv.initialized = false;
377 }
378 
379 
380 /*
381  * Fence debugfs
382  */
383 #if defined(CONFIG_DEBUG_FS)
384 static int radeon_debugfs_fence_info(struct seq_file *m, void *data)
385 {
386 	struct drm_info_node *node = (struct drm_info_node *)m->private;
387 	struct drm_device *dev = node->minor->dev;
388 	struct radeon_device *rdev = dev->dev_private;
389 	struct radeon_fence *fence;
390 
391 	seq_printf(m, "Last signaled fence 0x%08X\n",
392 		   RREG32(rdev->fence_drv.scratch_reg));
393 	if (!list_empty(&rdev->fence_drv.emited)) {
394 		   fence = list_entry(rdev->fence_drv.emited.prev,
395 				      struct radeon_fence, list);
396 		   seq_printf(m, "Last emited fence %p with 0x%08X\n",
397 			      fence,  fence->seq);
398 	}
399 	return 0;
400 }
401 
402 static struct drm_info_list radeon_debugfs_fence_list[] = {
403 	{"radeon_fence_info", &radeon_debugfs_fence_info, 0, NULL},
404 };
405 #endif
406 
407 int radeon_debugfs_fence_init(struct radeon_device *rdev)
408 {
409 #if defined(CONFIG_DEBUG_FS)
410 	return radeon_debugfs_add_files(rdev, radeon_debugfs_fence_list, 1);
411 #else
412 	return 0;
413 #endif
414 }
415