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 #include "radeon_trace.h"
42 
43 int radeon_fence_emit(struct radeon_device *rdev, struct radeon_fence *fence)
44 {
45 	unsigned long irq_flags;
46 
47 	write_lock_irqsave(&rdev->fence_drv.lock, irq_flags);
48 	if (fence->emited) {
49 		write_unlock_irqrestore(&rdev->fence_drv.lock, irq_flags);
50 		return 0;
51 	}
52 	fence->seq = atomic_add_return(1, &rdev->fence_drv.seq);
53 	if (!rdev->cp.ready) {
54 		/* FIXME: cp is not running assume everythings is done right
55 		 * away
56 		 */
57 		WREG32(rdev->fence_drv.scratch_reg, fence->seq);
58 	} else
59 		radeon_fence_ring_emit(rdev, fence);
60 
61 	trace_radeon_fence_emit(rdev->ddev, fence->seq);
62 	fence->emited = true;
63 	list_del(&fence->list);
64 	list_add_tail(&fence->list, &rdev->fence_drv.emited);
65 	write_unlock_irqrestore(&rdev->fence_drv.lock, irq_flags);
66 	return 0;
67 }
68 
69 static bool radeon_fence_poll_locked(struct radeon_device *rdev)
70 {
71 	struct radeon_fence *fence;
72 	struct list_head *i, *n;
73 	uint32_t seq;
74 	bool wake = false;
75 	unsigned long cjiffies;
76 
77 	if (rdev->wb.enabled) {
78 		u32 scratch_index;
79 		if (rdev->wb.use_event)
80 			scratch_index = R600_WB_EVENT_OFFSET + rdev->fence_drv.scratch_reg - rdev->scratch.reg_base;
81 		else
82 			scratch_index = RADEON_WB_SCRATCH_OFFSET + rdev->fence_drv.scratch_reg - rdev->scratch.reg_base;
83 		seq = rdev->wb.wb[scratch_index/4];
84 	} else
85 		seq = RREG32(rdev->fence_drv.scratch_reg);
86 	if (seq != rdev->fence_drv.last_seq) {
87 		rdev->fence_drv.last_seq = seq;
88 		rdev->fence_drv.last_jiffies = jiffies;
89 		rdev->fence_drv.last_timeout = RADEON_FENCE_JIFFIES_TIMEOUT;
90 	} else {
91 		cjiffies = jiffies;
92 		if (time_after(cjiffies, rdev->fence_drv.last_jiffies)) {
93 			cjiffies -= rdev->fence_drv.last_jiffies;
94 			if (time_after(rdev->fence_drv.last_timeout, cjiffies)) {
95 				/* update the timeout */
96 				rdev->fence_drv.last_timeout -= cjiffies;
97 			} else {
98 				/* the 500ms timeout is elapsed we should test
99 				 * for GPU lockup
100 				 */
101 				rdev->fence_drv.last_timeout = 1;
102 			}
103 		} else {
104 			/* wrap around update last jiffies, we will just wait
105 			 * a little longer
106 			 */
107 			rdev->fence_drv.last_jiffies = cjiffies;
108 		}
109 		return false;
110 	}
111 	n = NULL;
112 	list_for_each(i, &rdev->fence_drv.emited) {
113 		fence = list_entry(i, struct radeon_fence, list);
114 		if (fence->seq == seq) {
115 			n = i;
116 			break;
117 		}
118 	}
119 	/* all fence previous to this one are considered as signaled */
120 	if (n) {
121 		i = n;
122 		do {
123 			n = i->prev;
124 			list_del(i);
125 			list_add_tail(i, &rdev->fence_drv.signaled);
126 			fence = list_entry(i, struct radeon_fence, list);
127 			fence->signaled = true;
128 			i = n;
129 		} while (i != &rdev->fence_drv.emited);
130 		wake = true;
131 	}
132 	return wake;
133 }
134 
135 static void radeon_fence_destroy(struct kref *kref)
136 {
137 	unsigned long irq_flags;
138         struct radeon_fence *fence;
139 
140 	fence = container_of(kref, struct radeon_fence, kref);
141 	write_lock_irqsave(&fence->rdev->fence_drv.lock, irq_flags);
142 	list_del(&fence->list);
143 	fence->emited = false;
144 	write_unlock_irqrestore(&fence->rdev->fence_drv.lock, irq_flags);
145 	kfree(fence);
146 }
147 
148 int radeon_fence_create(struct radeon_device *rdev, struct radeon_fence **fence)
149 {
150 	unsigned long irq_flags;
151 
152 	*fence = kmalloc(sizeof(struct radeon_fence), GFP_KERNEL);
153 	if ((*fence) == NULL) {
154 		return -ENOMEM;
155 	}
156 	kref_init(&((*fence)->kref));
157 	(*fence)->rdev = rdev;
158 	(*fence)->emited = false;
159 	(*fence)->signaled = false;
160 	(*fence)->seq = 0;
161 	INIT_LIST_HEAD(&(*fence)->list);
162 
163 	write_lock_irqsave(&rdev->fence_drv.lock, irq_flags);
164 	list_add_tail(&(*fence)->list, &rdev->fence_drv.created);
165 	write_unlock_irqrestore(&rdev->fence_drv.lock, irq_flags);
166 	return 0;
167 }
168 
169 
170 bool radeon_fence_signaled(struct radeon_fence *fence)
171 {
172 	unsigned long irq_flags;
173 	bool signaled = false;
174 
175 	if (!fence)
176 		return true;
177 
178 	if (fence->rdev->gpu_lockup)
179 		return true;
180 
181 	write_lock_irqsave(&fence->rdev->fence_drv.lock, irq_flags);
182 	signaled = fence->signaled;
183 	/* if we are shuting down report all fence as signaled */
184 	if (fence->rdev->shutdown) {
185 		signaled = true;
186 	}
187 	if (!fence->emited) {
188 		WARN(1, "Querying an unemited fence : %p !\n", fence);
189 		signaled = true;
190 	}
191 	if (!signaled) {
192 		radeon_fence_poll_locked(fence->rdev);
193 		signaled = fence->signaled;
194 	}
195 	write_unlock_irqrestore(&fence->rdev->fence_drv.lock, irq_flags);
196 	return signaled;
197 }
198 
199 int radeon_fence_wait(struct radeon_fence *fence, bool intr)
200 {
201 	struct radeon_device *rdev;
202 	unsigned long irq_flags, timeout;
203 	u32 seq;
204 	int r;
205 
206 	if (fence == NULL) {
207 		WARN(1, "Querying an invalid fence : %p !\n", fence);
208 		return 0;
209 	}
210 	rdev = fence->rdev;
211 	if (radeon_fence_signaled(fence)) {
212 		return 0;
213 	}
214 	timeout = rdev->fence_drv.last_timeout;
215 retry:
216 	/* save current sequence used to check for GPU lockup */
217 	seq = rdev->fence_drv.last_seq;
218 	trace_radeon_fence_wait_begin(rdev->ddev, seq);
219 	if (intr) {
220 		radeon_irq_kms_sw_irq_get(rdev);
221 		r = wait_event_interruptible_timeout(rdev->fence_drv.queue,
222 				radeon_fence_signaled(fence), timeout);
223 		radeon_irq_kms_sw_irq_put(rdev);
224 		if (unlikely(r < 0)) {
225 			return r;
226 		}
227 	} else {
228 		radeon_irq_kms_sw_irq_get(rdev);
229 		r = wait_event_timeout(rdev->fence_drv.queue,
230 			 radeon_fence_signaled(fence), timeout);
231 		radeon_irq_kms_sw_irq_put(rdev);
232 	}
233 	trace_radeon_fence_wait_end(rdev->ddev, seq);
234 	if (unlikely(!radeon_fence_signaled(fence))) {
235 		/* we were interrupted for some reason and fence isn't
236 		 * isn't signaled yet, resume wait
237 		 */
238 		if (r) {
239 			timeout = r;
240 			goto retry;
241 		}
242 		/* don't protect read access to rdev->fence_drv.last_seq
243 		 * if we experiencing a lockup the value doesn't change
244 		 */
245 		if (seq == rdev->fence_drv.last_seq && radeon_gpu_is_lockup(rdev)) {
246 			/* good news we believe it's a lockup */
247 			WARN(1, "GPU lockup (waiting for 0x%08X last fence id 0x%08X)\n",
248 			     fence->seq, seq);
249 			/* FIXME: what should we do ? marking everyone
250 			 * as signaled for now
251 			 */
252 			rdev->gpu_lockup = true;
253 			r = radeon_gpu_reset(rdev);
254 			if (r)
255 				return r;
256 			WREG32(rdev->fence_drv.scratch_reg, fence->seq);
257 			rdev->gpu_lockup = false;
258 		}
259 		timeout = RADEON_FENCE_JIFFIES_TIMEOUT;
260 		write_lock_irqsave(&rdev->fence_drv.lock, irq_flags);
261 		rdev->fence_drv.last_timeout = RADEON_FENCE_JIFFIES_TIMEOUT;
262 		rdev->fence_drv.last_jiffies = jiffies;
263 		write_unlock_irqrestore(&rdev->fence_drv.lock, irq_flags);
264 		goto retry;
265 	}
266 	return 0;
267 }
268 
269 int radeon_fence_wait_next(struct radeon_device *rdev)
270 {
271 	unsigned long irq_flags;
272 	struct radeon_fence *fence;
273 	int r;
274 
275 	if (rdev->gpu_lockup) {
276 		return 0;
277 	}
278 	write_lock_irqsave(&rdev->fence_drv.lock, irq_flags);
279 	if (list_empty(&rdev->fence_drv.emited)) {
280 		write_unlock_irqrestore(&rdev->fence_drv.lock, irq_flags);
281 		return 0;
282 	}
283 	fence = list_entry(rdev->fence_drv.emited.next,
284 			   struct radeon_fence, list);
285 	radeon_fence_ref(fence);
286 	write_unlock_irqrestore(&rdev->fence_drv.lock, irq_flags);
287 	r = radeon_fence_wait(fence, false);
288 	radeon_fence_unref(&fence);
289 	return r;
290 }
291 
292 int radeon_fence_wait_last(struct radeon_device *rdev)
293 {
294 	unsigned long irq_flags;
295 	struct radeon_fence *fence;
296 	int r;
297 
298 	if (rdev->gpu_lockup) {
299 		return 0;
300 	}
301 	write_lock_irqsave(&rdev->fence_drv.lock, irq_flags);
302 	if (list_empty(&rdev->fence_drv.emited)) {
303 		write_unlock_irqrestore(&rdev->fence_drv.lock, irq_flags);
304 		return 0;
305 	}
306 	fence = list_entry(rdev->fence_drv.emited.prev,
307 			   struct radeon_fence, list);
308 	radeon_fence_ref(fence);
309 	write_unlock_irqrestore(&rdev->fence_drv.lock, irq_flags);
310 	r = radeon_fence_wait(fence, false);
311 	radeon_fence_unref(&fence);
312 	return r;
313 }
314 
315 struct radeon_fence *radeon_fence_ref(struct radeon_fence *fence)
316 {
317 	kref_get(&fence->kref);
318 	return fence;
319 }
320 
321 void radeon_fence_unref(struct radeon_fence **fence)
322 {
323 	struct radeon_fence *tmp = *fence;
324 
325 	*fence = NULL;
326 	if (tmp) {
327 		kref_put(&tmp->kref, &radeon_fence_destroy);
328 	}
329 }
330 
331 void radeon_fence_process(struct radeon_device *rdev)
332 {
333 	unsigned long irq_flags;
334 	bool wake;
335 
336 	write_lock_irqsave(&rdev->fence_drv.lock, irq_flags);
337 	wake = radeon_fence_poll_locked(rdev);
338 	write_unlock_irqrestore(&rdev->fence_drv.lock, irq_flags);
339 	if (wake) {
340 		wake_up_all(&rdev->fence_drv.queue);
341 	}
342 }
343 
344 int radeon_fence_driver_init(struct radeon_device *rdev)
345 {
346 	unsigned long irq_flags;
347 	int r;
348 
349 	write_lock_irqsave(&rdev->fence_drv.lock, irq_flags);
350 	r = radeon_scratch_get(rdev, &rdev->fence_drv.scratch_reg);
351 	if (r) {
352 		dev_err(rdev->dev, "fence failed to get scratch register\n");
353 		write_unlock_irqrestore(&rdev->fence_drv.lock, irq_flags);
354 		return r;
355 	}
356 	WREG32(rdev->fence_drv.scratch_reg, 0);
357 	atomic_set(&rdev->fence_drv.seq, 0);
358 	INIT_LIST_HEAD(&rdev->fence_drv.created);
359 	INIT_LIST_HEAD(&rdev->fence_drv.emited);
360 	INIT_LIST_HEAD(&rdev->fence_drv.signaled);
361 	init_waitqueue_head(&rdev->fence_drv.queue);
362 	rdev->fence_drv.initialized = true;
363 	write_unlock_irqrestore(&rdev->fence_drv.lock, irq_flags);
364 	if (radeon_debugfs_fence_init(rdev)) {
365 		dev_err(rdev->dev, "fence debugfs file creation failed\n");
366 	}
367 	return 0;
368 }
369 
370 void radeon_fence_driver_fini(struct radeon_device *rdev)
371 {
372 	unsigned long irq_flags;
373 
374 	if (!rdev->fence_drv.initialized)
375 		return;
376 	wake_up_all(&rdev->fence_drv.queue);
377 	write_lock_irqsave(&rdev->fence_drv.lock, irq_flags);
378 	radeon_scratch_free(rdev, rdev->fence_drv.scratch_reg);
379 	write_unlock_irqrestore(&rdev->fence_drv.lock, irq_flags);
380 	rdev->fence_drv.initialized = false;
381 }
382 
383 
384 /*
385  * Fence debugfs
386  */
387 #if defined(CONFIG_DEBUG_FS)
388 static int radeon_debugfs_fence_info(struct seq_file *m, void *data)
389 {
390 	struct drm_info_node *node = (struct drm_info_node *)m->private;
391 	struct drm_device *dev = node->minor->dev;
392 	struct radeon_device *rdev = dev->dev_private;
393 	struct radeon_fence *fence;
394 
395 	seq_printf(m, "Last signaled fence 0x%08X\n",
396 		   RREG32(rdev->fence_drv.scratch_reg));
397 	if (!list_empty(&rdev->fence_drv.emited)) {
398 		   fence = list_entry(rdev->fence_drv.emited.prev,
399 				      struct radeon_fence, list);
400 		   seq_printf(m, "Last emited fence %p with 0x%08X\n",
401 			      fence,  fence->seq);
402 	}
403 	return 0;
404 }
405 
406 static struct drm_info_list radeon_debugfs_fence_list[] = {
407 	{"radeon_fence_info", &radeon_debugfs_fence_info, 0, NULL},
408 };
409 #endif
410 
411 int radeon_debugfs_fence_init(struct radeon_device *rdev)
412 {
413 #if defined(CONFIG_DEBUG_FS)
414 	return radeon_debugfs_add_files(rdev, radeon_debugfs_fence_list, 1);
415 #else
416 	return 0;
417 #endif
418 }
419