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_move_tail(&fence->list, &rdev->fence_drv.emited);
64 	write_unlock_irqrestore(&rdev->fence_drv.lock, irq_flags);
65 	return 0;
66 }
67 
68 static bool radeon_fence_poll_locked(struct radeon_device *rdev)
69 {
70 	struct radeon_fence *fence;
71 	struct list_head *i, *n;
72 	uint32_t seq;
73 	bool wake = false;
74 	unsigned long cjiffies;
75 
76 	if (rdev->wb.enabled) {
77 		u32 scratch_index;
78 		if (rdev->wb.use_event)
79 			scratch_index = R600_WB_EVENT_OFFSET + rdev->fence_drv.scratch_reg - rdev->scratch.reg_base;
80 		else
81 			scratch_index = RADEON_WB_SCRATCH_OFFSET + rdev->fence_drv.scratch_reg - rdev->scratch.reg_base;
82 		seq = rdev->wb.wb[scratch_index/4];
83 	} else
84 		seq = RREG32(rdev->fence_drv.scratch_reg);
85 	if (seq != rdev->fence_drv.last_seq) {
86 		rdev->fence_drv.last_seq = seq;
87 		rdev->fence_drv.last_jiffies = jiffies;
88 		rdev->fence_drv.last_timeout = RADEON_FENCE_JIFFIES_TIMEOUT;
89 	} else {
90 		cjiffies = jiffies;
91 		if (time_after(cjiffies, rdev->fence_drv.last_jiffies)) {
92 			cjiffies -= rdev->fence_drv.last_jiffies;
93 			if (time_after(rdev->fence_drv.last_timeout, cjiffies)) {
94 				/* update the timeout */
95 				rdev->fence_drv.last_timeout -= cjiffies;
96 			} else {
97 				/* the 500ms timeout is elapsed we should test
98 				 * for GPU lockup
99 				 */
100 				rdev->fence_drv.last_timeout = 1;
101 			}
102 		} else {
103 			/* wrap around update last jiffies, we will just wait
104 			 * a little longer
105 			 */
106 			rdev->fence_drv.last_jiffies = cjiffies;
107 		}
108 		return false;
109 	}
110 	n = NULL;
111 	list_for_each(i, &rdev->fence_drv.emited) {
112 		fence = list_entry(i, struct radeon_fence, list);
113 		if (fence->seq == seq) {
114 			n = i;
115 			break;
116 		}
117 	}
118 	/* all fence previous to this one are considered as signaled */
119 	if (n) {
120 		i = n;
121 		do {
122 			n = i->prev;
123 			list_move_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 	trace_radeon_fence_wait_begin(rdev->ddev, seq);
217 	if (intr) {
218 		radeon_irq_kms_sw_irq_get(rdev);
219 		r = wait_event_interruptible_timeout(rdev->fence_drv.queue,
220 				radeon_fence_signaled(fence), timeout);
221 		radeon_irq_kms_sw_irq_put(rdev);
222 		if (unlikely(r < 0)) {
223 			return r;
224 		}
225 	} else {
226 		radeon_irq_kms_sw_irq_get(rdev);
227 		r = wait_event_timeout(rdev->fence_drv.queue,
228 			 radeon_fence_signaled(fence), timeout);
229 		radeon_irq_kms_sw_irq_put(rdev);
230 	}
231 	trace_radeon_fence_wait_end(rdev->ddev, seq);
232 	if (unlikely(!radeon_fence_signaled(fence))) {
233 		/* we were interrupted for some reason and fence isn't
234 		 * isn't signaled yet, resume wait
235 		 */
236 		if (r) {
237 			timeout = r;
238 			goto retry;
239 		}
240 		/* don't protect read access to rdev->fence_drv.last_seq
241 		 * if we experiencing a lockup the value doesn't change
242 		 */
243 		if (seq == rdev->fence_drv.last_seq && radeon_gpu_is_lockup(rdev)) {
244 			/* good news we believe it's a lockup */
245 			WARN(1, "GPU lockup (waiting for 0x%08X last fence id 0x%08X)\n",
246 			     fence->seq, seq);
247 			/* FIXME: what should we do ? marking everyone
248 			 * as signaled for now
249 			 */
250 			rdev->gpu_lockup = true;
251 			r = radeon_gpu_reset(rdev);
252 			if (r)
253 				return r;
254 			WREG32(rdev->fence_drv.scratch_reg, fence->seq);
255 			rdev->gpu_lockup = false;
256 		}
257 		timeout = RADEON_FENCE_JIFFIES_TIMEOUT;
258 		write_lock_irqsave(&rdev->fence_drv.lock, irq_flags);
259 		rdev->fence_drv.last_timeout = RADEON_FENCE_JIFFIES_TIMEOUT;
260 		rdev->fence_drv.last_jiffies = jiffies;
261 		write_unlock_irqrestore(&rdev->fence_drv.lock, irq_flags);
262 		goto retry;
263 	}
264 	return 0;
265 }
266 
267 int radeon_fence_wait_next(struct radeon_device *rdev)
268 {
269 	unsigned long irq_flags;
270 	struct radeon_fence *fence;
271 	int r;
272 
273 	if (rdev->gpu_lockup) {
274 		return 0;
275 	}
276 	write_lock_irqsave(&rdev->fence_drv.lock, irq_flags);
277 	if (list_empty(&rdev->fence_drv.emited)) {
278 		write_unlock_irqrestore(&rdev->fence_drv.lock, irq_flags);
279 		return 0;
280 	}
281 	fence = list_entry(rdev->fence_drv.emited.next,
282 			   struct radeon_fence, list);
283 	radeon_fence_ref(fence);
284 	write_unlock_irqrestore(&rdev->fence_drv.lock, irq_flags);
285 	r = radeon_fence_wait(fence, false);
286 	radeon_fence_unref(&fence);
287 	return r;
288 }
289 
290 int radeon_fence_wait_last(struct radeon_device *rdev)
291 {
292 	unsigned long irq_flags;
293 	struct radeon_fence *fence;
294 	int r;
295 
296 	if (rdev->gpu_lockup) {
297 		return 0;
298 	}
299 	write_lock_irqsave(&rdev->fence_drv.lock, irq_flags);
300 	if (list_empty(&rdev->fence_drv.emited)) {
301 		write_unlock_irqrestore(&rdev->fence_drv.lock, irq_flags);
302 		return 0;
303 	}
304 	fence = list_entry(rdev->fence_drv.emited.prev,
305 			   struct radeon_fence, list);
306 	radeon_fence_ref(fence);
307 	write_unlock_irqrestore(&rdev->fence_drv.lock, irq_flags);
308 	r = radeon_fence_wait(fence, false);
309 	radeon_fence_unref(&fence);
310 	return r;
311 }
312 
313 struct radeon_fence *radeon_fence_ref(struct radeon_fence *fence)
314 {
315 	kref_get(&fence->kref);
316 	return fence;
317 }
318 
319 void radeon_fence_unref(struct radeon_fence **fence)
320 {
321 	struct radeon_fence *tmp = *fence;
322 
323 	*fence = NULL;
324 	if (tmp) {
325 		kref_put(&tmp->kref, &radeon_fence_destroy);
326 	}
327 }
328 
329 void radeon_fence_process(struct radeon_device *rdev)
330 {
331 	unsigned long irq_flags;
332 	bool wake;
333 
334 	write_lock_irqsave(&rdev->fence_drv.lock, irq_flags);
335 	wake = radeon_fence_poll_locked(rdev);
336 	write_unlock_irqrestore(&rdev->fence_drv.lock, irq_flags);
337 	if (wake) {
338 		wake_up_all(&rdev->fence_drv.queue);
339 	}
340 }
341 
342 int radeon_fence_driver_init(struct radeon_device *rdev)
343 {
344 	unsigned long irq_flags;
345 	int r;
346 
347 	write_lock_irqsave(&rdev->fence_drv.lock, irq_flags);
348 	r = radeon_scratch_get(rdev, &rdev->fence_drv.scratch_reg);
349 	if (r) {
350 		dev_err(rdev->dev, "fence failed to get scratch register\n");
351 		write_unlock_irqrestore(&rdev->fence_drv.lock, irq_flags);
352 		return r;
353 	}
354 	WREG32(rdev->fence_drv.scratch_reg, 0);
355 	atomic_set(&rdev->fence_drv.seq, 0);
356 	INIT_LIST_HEAD(&rdev->fence_drv.created);
357 	INIT_LIST_HEAD(&rdev->fence_drv.emited);
358 	INIT_LIST_HEAD(&rdev->fence_drv.signaled);
359 	init_waitqueue_head(&rdev->fence_drv.queue);
360 	rdev->fence_drv.initialized = true;
361 	write_unlock_irqrestore(&rdev->fence_drv.lock, irq_flags);
362 	if (radeon_debugfs_fence_init(rdev)) {
363 		dev_err(rdev->dev, "fence debugfs file creation failed\n");
364 	}
365 	return 0;
366 }
367 
368 void radeon_fence_driver_fini(struct radeon_device *rdev)
369 {
370 	unsigned long irq_flags;
371 
372 	if (!rdev->fence_drv.initialized)
373 		return;
374 	wake_up_all(&rdev->fence_drv.queue);
375 	write_lock_irqsave(&rdev->fence_drv.lock, irq_flags);
376 	radeon_scratch_free(rdev, rdev->fence_drv.scratch_reg);
377 	write_unlock_irqrestore(&rdev->fence_drv.lock, irq_flags);
378 	rdev->fence_drv.initialized = false;
379 }
380 
381 
382 /*
383  * Fence debugfs
384  */
385 #if defined(CONFIG_DEBUG_FS)
386 static int radeon_debugfs_fence_info(struct seq_file *m, void *data)
387 {
388 	struct drm_info_node *node = (struct drm_info_node *)m->private;
389 	struct drm_device *dev = node->minor->dev;
390 	struct radeon_device *rdev = dev->dev_private;
391 	struct radeon_fence *fence;
392 
393 	seq_printf(m, "Last signaled fence 0x%08X\n",
394 		   RREG32(rdev->fence_drv.scratch_reg));
395 	if (!list_empty(&rdev->fence_drv.emited)) {
396 		   fence = list_entry(rdev->fence_drv.emited.prev,
397 				      struct radeon_fence, list);
398 		   seq_printf(m, "Last emited fence %p with 0x%08X\n",
399 			      fence,  fence->seq);
400 	}
401 	return 0;
402 }
403 
404 static struct drm_info_list radeon_debugfs_fence_list[] = {
405 	{"radeon_fence_info", &radeon_debugfs_fence_info, 0, NULL},
406 };
407 #endif
408 
409 int radeon_debugfs_fence_init(struct radeon_device *rdev)
410 {
411 #if defined(CONFIG_DEBUG_FS)
412 	return radeon_debugfs_add_files(rdev, radeon_debugfs_fence_list, 1);
413 #else
414 	return 0;
415 #endif
416 }
417