xref: /openbmc/linux/drivers/gpu/drm/i915/gt/mock_engine.c (revision 2326f3cd)
1 // SPDX-License-Identifier: MIT
2 /*
3  * Copyright © 2016 Intel Corporation
4  */
5 
6 #include "gem/i915_gem_context.h"
7 #include "gt/intel_ring.h"
8 
9 #include "i915_drv.h"
10 #include "intel_context.h"
11 #include "intel_engine_pm.h"
12 
13 #include "mock_engine.h"
14 #include "selftests/mock_request.h"
15 
16 static int mock_timeline_pin(struct intel_timeline *tl)
17 {
18 	int err;
19 
20 	if (WARN_ON(!i915_gem_object_trylock(tl->hwsp_ggtt->obj)))
21 		return -EBUSY;
22 
23 	err = intel_timeline_pin_map(tl);
24 	i915_gem_object_unlock(tl->hwsp_ggtt->obj);
25 	if (err)
26 		return err;
27 
28 	atomic_inc(&tl->pin_count);
29 	return 0;
30 }
31 
32 static void mock_timeline_unpin(struct intel_timeline *tl)
33 {
34 	GEM_BUG_ON(!atomic_read(&tl->pin_count));
35 	atomic_dec(&tl->pin_count);
36 }
37 
38 static struct intel_ring *mock_ring(struct intel_engine_cs *engine)
39 {
40 	const unsigned long sz = PAGE_SIZE / 2;
41 	struct intel_ring *ring;
42 
43 	ring = kzalloc(sizeof(*ring) + sz, GFP_KERNEL);
44 	if (!ring)
45 		return NULL;
46 
47 	kref_init(&ring->ref);
48 	ring->size = sz;
49 	ring->effective_size = sz;
50 	ring->vaddr = (void *)(ring + 1);
51 	atomic_set(&ring->pin_count, 1);
52 
53 	ring->vma = i915_vma_alloc();
54 	if (!ring->vma) {
55 		kfree(ring);
56 		return NULL;
57 	}
58 	i915_active_init(&ring->vma->active, NULL, NULL, 0);
59 	__set_bit(I915_VMA_GGTT_BIT, __i915_vma_flags(ring->vma));
60 	__set_bit(DRM_MM_NODE_ALLOCATED_BIT, &ring->vma->node.flags);
61 	ring->vma->node.size = sz;
62 
63 	intel_ring_update_space(ring);
64 
65 	return ring;
66 }
67 
68 static void mock_ring_free(struct intel_ring *ring)
69 {
70 	i915_active_fini(&ring->vma->active);
71 	i915_vma_free(ring->vma);
72 
73 	kfree(ring);
74 }
75 
76 static struct i915_request *first_request(struct mock_engine *engine)
77 {
78 	return list_first_entry_or_null(&engine->hw_queue,
79 					struct i915_request,
80 					mock.link);
81 }
82 
83 static void advance(struct i915_request *request)
84 {
85 	list_del_init(&request->mock.link);
86 	i915_request_mark_complete(request);
87 	GEM_BUG_ON(!i915_request_completed(request));
88 
89 	intel_engine_signal_breadcrumbs(request->engine);
90 }
91 
92 static void hw_delay_complete(struct timer_list *t)
93 {
94 	struct mock_engine *engine = from_timer(engine, t, hw_delay);
95 	struct i915_request *request;
96 	unsigned long flags;
97 
98 	spin_lock_irqsave(&engine->hw_lock, flags);
99 
100 	/* Timer fired, first request is complete */
101 	request = first_request(engine);
102 	if (request)
103 		advance(request);
104 
105 	/*
106 	 * Also immediately signal any subsequent 0-delay requests, but
107 	 * requeue the timer for the next delayed request.
108 	 */
109 	while ((request = first_request(engine))) {
110 		if (request->mock.delay) {
111 			mod_timer(&engine->hw_delay,
112 				  jiffies + request->mock.delay);
113 			break;
114 		}
115 
116 		advance(request);
117 	}
118 
119 	spin_unlock_irqrestore(&engine->hw_lock, flags);
120 }
121 
122 static void mock_context_unpin(struct intel_context *ce)
123 {
124 }
125 
126 static void mock_context_post_unpin(struct intel_context *ce)
127 {
128 }
129 
130 static void mock_context_destroy(struct kref *ref)
131 {
132 	struct intel_context *ce = container_of(ref, typeof(*ce), ref);
133 
134 	GEM_BUG_ON(intel_context_is_pinned(ce));
135 
136 	if (test_bit(CONTEXT_ALLOC_BIT, &ce->flags)) {
137 		mock_ring_free(ce->ring);
138 		mock_timeline_unpin(ce->timeline);
139 	}
140 
141 	intel_context_fini(ce);
142 	intel_context_free(ce);
143 }
144 
145 static int mock_context_alloc(struct intel_context *ce)
146 {
147 	int err;
148 
149 	ce->ring = mock_ring(ce->engine);
150 	if (!ce->ring)
151 		return -ENOMEM;
152 
153 	ce->timeline = intel_timeline_create(ce->engine->gt);
154 	if (IS_ERR(ce->timeline)) {
155 		kfree(ce->engine);
156 		return PTR_ERR(ce->timeline);
157 	}
158 
159 	err = mock_timeline_pin(ce->timeline);
160 	if (err) {
161 		intel_timeline_put(ce->timeline);
162 		ce->timeline = NULL;
163 		return err;
164 	}
165 
166 	return 0;
167 }
168 
169 static int mock_context_pre_pin(struct intel_context *ce,
170 				struct i915_gem_ww_ctx *ww, void **unused)
171 {
172 	return 0;
173 }
174 
175 static int mock_context_pin(struct intel_context *ce, void *unused)
176 {
177 	return 0;
178 }
179 
180 static void mock_context_reset(struct intel_context *ce)
181 {
182 }
183 
184 static const struct intel_context_ops mock_context_ops = {
185 	.alloc = mock_context_alloc,
186 
187 	.pre_pin = mock_context_pre_pin,
188 	.pin = mock_context_pin,
189 	.unpin = mock_context_unpin,
190 	.post_unpin = mock_context_post_unpin,
191 
192 	.enter = intel_context_enter_engine,
193 	.exit = intel_context_exit_engine,
194 
195 	.reset = mock_context_reset,
196 	.destroy = mock_context_destroy,
197 };
198 
199 static int mock_request_alloc(struct i915_request *request)
200 {
201 	INIT_LIST_HEAD(&request->mock.link);
202 	request->mock.delay = 0;
203 
204 	return 0;
205 }
206 
207 static int mock_emit_flush(struct i915_request *request,
208 			   unsigned int flags)
209 {
210 	return 0;
211 }
212 
213 static u32 *mock_emit_breadcrumb(struct i915_request *request, u32 *cs)
214 {
215 	return cs;
216 }
217 
218 static void mock_submit_request(struct i915_request *request)
219 {
220 	struct mock_engine *engine =
221 		container_of(request->engine, typeof(*engine), base);
222 	unsigned long flags;
223 
224 	i915_request_submit(request);
225 
226 	spin_lock_irqsave(&engine->hw_lock, flags);
227 	list_add_tail(&request->mock.link, &engine->hw_queue);
228 	if (list_is_first(&request->mock.link, &engine->hw_queue)) {
229 		if (request->mock.delay)
230 			mod_timer(&engine->hw_delay,
231 				  jiffies + request->mock.delay);
232 		else
233 			advance(request);
234 	}
235 	spin_unlock_irqrestore(&engine->hw_lock, flags);
236 }
237 
238 static void mock_add_to_engine(struct i915_request *rq)
239 {
240 	lockdep_assert_held(&rq->engine->sched_engine->lock);
241 	list_move_tail(&rq->sched.link, &rq->engine->sched_engine->requests);
242 }
243 
244 static void mock_remove_from_engine(struct i915_request *rq)
245 {
246 	struct intel_engine_cs *engine, *locked;
247 
248 	/*
249 	 * Virtual engines complicate acquiring the engine timeline lock,
250 	 * as their rq->engine pointer is not stable until under that
251 	 * engine lock. The simple ploy we use is to take the lock then
252 	 * check that the rq still belongs to the newly locked engine.
253 	 */
254 
255 	locked = READ_ONCE(rq->engine);
256 	spin_lock_irq(&locked->sched_engine->lock);
257 	while (unlikely(locked != (engine = READ_ONCE(rq->engine)))) {
258 		spin_unlock(&locked->sched_engine->lock);
259 		spin_lock(&engine->sched_engine->lock);
260 		locked = engine;
261 	}
262 	list_del_init(&rq->sched.link);
263 	spin_unlock_irq(&locked->sched_engine->lock);
264 }
265 
266 static void mock_reset_prepare(struct intel_engine_cs *engine)
267 {
268 }
269 
270 static void mock_reset_rewind(struct intel_engine_cs *engine, bool stalled)
271 {
272 	GEM_BUG_ON(stalled);
273 }
274 
275 static void mock_reset_cancel(struct intel_engine_cs *engine)
276 {
277 	struct mock_engine *mock =
278 		container_of(engine, typeof(*mock), base);
279 	struct i915_request *rq;
280 	unsigned long flags;
281 
282 	del_timer_sync(&mock->hw_delay);
283 
284 	spin_lock_irqsave(&engine->sched_engine->lock, flags);
285 
286 	/* Mark all submitted requests as skipped. */
287 	list_for_each_entry(rq, &engine->sched_engine->requests, sched.link)
288 		i915_request_put(i915_request_mark_eio(rq));
289 	intel_engine_signal_breadcrumbs(engine);
290 
291 	/* Cancel and submit all pending requests. */
292 	list_for_each_entry(rq, &mock->hw_queue, mock.link) {
293 		if (i915_request_mark_eio(rq)) {
294 			__i915_request_submit(rq);
295 			i915_request_put(rq);
296 		}
297 	}
298 	INIT_LIST_HEAD(&mock->hw_queue);
299 
300 	spin_unlock_irqrestore(&engine->sched_engine->lock, flags);
301 }
302 
303 static void mock_reset_finish(struct intel_engine_cs *engine)
304 {
305 }
306 
307 static void mock_engine_release(struct intel_engine_cs *engine)
308 {
309 	struct mock_engine *mock =
310 		container_of(engine, typeof(*mock), base);
311 
312 	GEM_BUG_ON(timer_pending(&mock->hw_delay));
313 
314 	i915_sched_engine_put(engine->sched_engine);
315 	intel_breadcrumbs_put(engine->breadcrumbs);
316 
317 	intel_context_unpin(engine->kernel_context);
318 	intel_context_put(engine->kernel_context);
319 
320 	intel_engine_fini_retire(engine);
321 }
322 
323 struct intel_engine_cs *mock_engine(struct drm_i915_private *i915,
324 				    const char *name,
325 				    int id)
326 {
327 	struct mock_engine *engine;
328 
329 	GEM_BUG_ON(id >= I915_NUM_ENGINES);
330 	GEM_BUG_ON(!i915->gt.uncore);
331 
332 	engine = kzalloc(sizeof(*engine) + PAGE_SIZE, GFP_KERNEL);
333 	if (!engine)
334 		return NULL;
335 
336 	/* minimal engine setup for requests */
337 	engine->base.i915 = i915;
338 	engine->base.gt = &i915->gt;
339 	engine->base.uncore = i915->gt.uncore;
340 	snprintf(engine->base.name, sizeof(engine->base.name), "%s", name);
341 	engine->base.id = id;
342 	engine->base.mask = BIT(id);
343 	engine->base.legacy_idx = INVALID_ENGINE;
344 	engine->base.instance = id;
345 	engine->base.status_page.addr = (void *)(engine + 1);
346 
347 	engine->base.cops = &mock_context_ops;
348 	engine->base.request_alloc = mock_request_alloc;
349 	engine->base.emit_flush = mock_emit_flush;
350 	engine->base.emit_fini_breadcrumb = mock_emit_breadcrumb;
351 	engine->base.submit_request = mock_submit_request;
352 	engine->base.add_active_request = mock_add_to_engine;
353 	engine->base.remove_active_request = mock_remove_from_engine;
354 
355 	engine->base.reset.prepare = mock_reset_prepare;
356 	engine->base.reset.rewind = mock_reset_rewind;
357 	engine->base.reset.cancel = mock_reset_cancel;
358 	engine->base.reset.finish = mock_reset_finish;
359 
360 	engine->base.release = mock_engine_release;
361 
362 	i915->gt.engine[id] = &engine->base;
363 	i915->gt.engine_class[0][id] = &engine->base;
364 
365 	/* fake hw queue */
366 	spin_lock_init(&engine->hw_lock);
367 	timer_setup(&engine->hw_delay, hw_delay_complete, 0);
368 	INIT_LIST_HEAD(&engine->hw_queue);
369 
370 	intel_engine_add_user(&engine->base);
371 
372 	return &engine->base;
373 }
374 
375 int mock_engine_init(struct intel_engine_cs *engine)
376 {
377 	struct intel_context *ce;
378 
379 	engine->sched_engine = i915_sched_engine_create(ENGINE_MOCK);
380 	if (!engine->sched_engine)
381 		return -ENOMEM;
382 	engine->sched_engine->private_data = engine;
383 
384 	intel_engine_init_execlists(engine);
385 	intel_engine_init__pm(engine);
386 	intel_engine_init_retire(engine);
387 
388 	engine->breadcrumbs = intel_breadcrumbs_create(NULL);
389 	if (!engine->breadcrumbs)
390 		goto err_schedule;
391 
392 	ce = create_kernel_context(engine);
393 	if (IS_ERR(ce))
394 		goto err_breadcrumbs;
395 
396 	/* We insist the kernel context is using the status_page */
397 	engine->status_page.vma = ce->timeline->hwsp_ggtt;
398 
399 	engine->kernel_context = ce;
400 	return 0;
401 
402 err_breadcrumbs:
403 	intel_breadcrumbs_put(engine->breadcrumbs);
404 err_schedule:
405 	i915_sched_engine_put(engine->sched_engine);
406 	return -ENOMEM;
407 }
408 
409 void mock_engine_flush(struct intel_engine_cs *engine)
410 {
411 	struct mock_engine *mock =
412 		container_of(engine, typeof(*mock), base);
413 	struct i915_request *request, *rn;
414 
415 	del_timer_sync(&mock->hw_delay);
416 
417 	spin_lock_irq(&mock->hw_lock);
418 	list_for_each_entry_safe(request, rn, &mock->hw_queue, mock.link)
419 		advance(request);
420 	spin_unlock_irq(&mock->hw_lock);
421 }
422 
423 void mock_engine_reset(struct intel_engine_cs *engine)
424 {
425 }
426