xref: /openbmc/linux/drivers/gpu/drm/lima/lima_sched.c (revision b830f94f) 
1 // SPDX-License-Identifier: GPL-2.0 OR MIT
2 /* Copyright 2017-2019 Qiang Yu <yuq825@gmail.com> */
3 
4 #include <linux/kthread.h>
5 #include <linux/slab.h>
6 #include <linux/xarray.h>
7 
8 #include "lima_drv.h"
9 #include "lima_sched.h"
10 #include "lima_vm.h"
11 #include "lima_mmu.h"
12 #include "lima_l2_cache.h"
13 #include "lima_object.h"
14 
15 struct lima_fence {
16 	struct dma_fence base;
17 	struct lima_sched_pipe *pipe;
18 };
19 
20 static struct kmem_cache *lima_fence_slab;
21 static int lima_fence_slab_refcnt;
22 
23 int lima_sched_slab_init(void)
24 {
25 	if (!lima_fence_slab) {
26 		lima_fence_slab = kmem_cache_create(
27 			"lima_fence", sizeof(struct lima_fence), 0,
28 			SLAB_HWCACHE_ALIGN, NULL);
29 		if (!lima_fence_slab)
30 			return -ENOMEM;
31 	}
32 
33 	lima_fence_slab_refcnt++;
34 	return 0;
35 }
36 
37 void lima_sched_slab_fini(void)
38 {
39 	if (!--lima_fence_slab_refcnt) {
40 		kmem_cache_destroy(lima_fence_slab);
41 		lima_fence_slab = NULL;
42 	}
43 }
44 
45 static inline struct lima_fence *to_lima_fence(struct dma_fence *fence)
46 {
47 	return container_of(fence, struct lima_fence, base);
48 }
49 
50 static const char *lima_fence_get_driver_name(struct dma_fence *fence)
51 {
52 	return "lima";
53 }
54 
55 static const char *lima_fence_get_timeline_name(struct dma_fence *fence)
56 {
57 	struct lima_fence *f = to_lima_fence(fence);
58 
59 	return f->pipe->base.name;
60 }
61 
62 static void lima_fence_release_rcu(struct rcu_head *rcu)
63 {
64 	struct dma_fence *f = container_of(rcu, struct dma_fence, rcu);
65 	struct lima_fence *fence = to_lima_fence(f);
66 
67 	kmem_cache_free(lima_fence_slab, fence);
68 }
69 
70 static void lima_fence_release(struct dma_fence *fence)
71 {
72 	struct lima_fence *f = to_lima_fence(fence);
73 
74 	call_rcu(&f->base.rcu, lima_fence_release_rcu);
75 }
76 
77 static const struct dma_fence_ops lima_fence_ops = {
78 	.get_driver_name = lima_fence_get_driver_name,
79 	.get_timeline_name = lima_fence_get_timeline_name,
80 	.release = lima_fence_release,
81 };
82 
83 static struct lima_fence *lima_fence_create(struct lima_sched_pipe *pipe)
84 {
85 	struct lima_fence *fence;
86 
87 	fence = kmem_cache_zalloc(lima_fence_slab, GFP_KERNEL);
88 	if (!fence)
89 		return NULL;
90 
91 	fence->pipe = pipe;
92 	dma_fence_init(&fence->base, &lima_fence_ops, &pipe->fence_lock,
93 		       pipe->fence_context, ++pipe->fence_seqno);
94 
95 	return fence;
96 }
97 
98 static inline struct lima_sched_task *to_lima_task(struct drm_sched_job *job)
99 {
100 	return container_of(job, struct lima_sched_task, base);
101 }
102 
103 static inline struct lima_sched_pipe *to_lima_pipe(struct drm_gpu_scheduler *sched)
104 {
105 	return container_of(sched, struct lima_sched_pipe, base);
106 }
107 
108 int lima_sched_task_init(struct lima_sched_task *task,
109 			 struct lima_sched_context *context,
110 			 struct lima_bo **bos, int num_bos,
111 			 struct lima_vm *vm)
112 {
113 	int err, i;
114 
115 	task->bos = kmemdup(bos, sizeof(*bos) * num_bos, GFP_KERNEL);
116 	if (!task->bos)
117 		return -ENOMEM;
118 
119 	for (i = 0; i < num_bos; i++)
120 		drm_gem_object_get(&bos[i]->gem);
121 
122 	err = drm_sched_job_init(&task->base, &context->base, vm);
123 	if (err) {
124 		kfree(task->bos);
125 		return err;
126 	}
127 
128 	task->num_bos = num_bos;
129 	task->vm = lima_vm_get(vm);
130 
131 	xa_init_flags(&task->deps, XA_FLAGS_ALLOC);
132 
133 	return 0;
134 }
135 
136 void lima_sched_task_fini(struct lima_sched_task *task)
137 {
138 	struct dma_fence *fence;
139 	unsigned long index;
140 	int i;
141 
142 	drm_sched_job_cleanup(&task->base);
143 
144 	xa_for_each(&task->deps, index, fence) {
145 		dma_fence_put(fence);
146 	}
147 	xa_destroy(&task->deps);
148 
149 	if (task->bos) {
150 		for (i = 0; i < task->num_bos; i++)
151 			drm_gem_object_put_unlocked(&task->bos[i]->gem);
152 		kfree(task->bos);
153 	}
154 
155 	lima_vm_put(task->vm);
156 }
157 
158 int lima_sched_context_init(struct lima_sched_pipe *pipe,
159 			    struct lima_sched_context *context,
160 			    atomic_t *guilty)
161 {
162 	struct drm_sched_rq *rq = pipe->base.sched_rq + DRM_SCHED_PRIORITY_NORMAL;
163 
164 	return drm_sched_entity_init(&context->base, &rq, 1, guilty);
165 }
166 
167 void lima_sched_context_fini(struct lima_sched_pipe *pipe,
168 			     struct lima_sched_context *context)
169 {
170 	drm_sched_entity_fini(&context->base);
171 }
172 
173 struct dma_fence *lima_sched_context_queue_task(struct lima_sched_context *context,
174 						struct lima_sched_task *task)
175 {
176 	struct dma_fence *fence = dma_fence_get(&task->base.s_fence->finished);
177 
178 	drm_sched_entity_push_job(&task->base, &context->base);
179 	return fence;
180 }
181 
182 static struct dma_fence *lima_sched_dependency(struct drm_sched_job *job,
183 					       struct drm_sched_entity *entity)
184 {
185 	struct lima_sched_task *task = to_lima_task(job);
186 
187 	if (!xa_empty(&task->deps))
188 		return xa_erase(&task->deps, task->last_dep++);
189 
190 	return NULL;
191 }
192 
193 static struct dma_fence *lima_sched_run_job(struct drm_sched_job *job)
194 {
195 	struct lima_sched_task *task = to_lima_task(job);
196 	struct lima_sched_pipe *pipe = to_lima_pipe(job->sched);
197 	struct lima_fence *fence;
198 	struct dma_fence *ret;
199 	struct lima_vm *vm = NULL, *last_vm = NULL;
200 	int i;
201 
202 	/* after GPU reset */
203 	if (job->s_fence->finished.error < 0)
204 		return NULL;
205 
206 	fence = lima_fence_create(pipe);
207 	if (!fence)
208 		return NULL;
209 	task->fence = &fence->base;
210 
211 	/* for caller usage of the fence, otherwise irq handler
212 	 * may consume the fence before caller use it
213 	 */
214 	ret = dma_fence_get(task->fence);
215 
216 	pipe->current_task = task;
217 
218 	/* this is needed for MMU to work correctly, otherwise GP/PP
219 	 * will hang or page fault for unknown reason after running for
220 	 * a while.
221 	 *
222 	 * Need to investigate:
223 	 * 1. is it related to TLB
224 	 * 2. how much performance will be affected by L2 cache flush
225 	 * 3. can we reduce the calling of this function because all
226 	 *    GP/PP use the same L2 cache on mali400
227 	 *
228 	 * TODO:
229 	 * 1. move this to task fini to save some wait time?
230 	 * 2. when GP/PP use different l2 cache, need PP wait GP l2
231 	 *    cache flush?
232 	 */
233 	for (i = 0; i < pipe->num_l2_cache; i++)
234 		lima_l2_cache_flush(pipe->l2_cache[i]);
235 
236 	if (task->vm != pipe->current_vm) {
237 		vm = lima_vm_get(task->vm);
238 		last_vm = pipe->current_vm;
239 		pipe->current_vm = task->vm;
240 	}
241 
242 	if (pipe->bcast_mmu)
243 		lima_mmu_switch_vm(pipe->bcast_mmu, vm);
244 	else {
245 		for (i = 0; i < pipe->num_mmu; i++)
246 			lima_mmu_switch_vm(pipe->mmu[i], vm);
247 	}
248 
249 	if (last_vm)
250 		lima_vm_put(last_vm);
251 
252 	pipe->error = false;
253 	pipe->task_run(pipe, task);
254 
255 	return task->fence;
256 }
257 
258 static void lima_sched_handle_error_task(struct lima_sched_pipe *pipe,
259 					 struct lima_sched_task *task)
260 {
261 	drm_sched_stop(&pipe->base, &task->base);
262 
263 	if (task)
264 		drm_sched_increase_karma(&task->base);
265 
266 	pipe->task_error(pipe);
267 
268 	if (pipe->bcast_mmu)
269 		lima_mmu_page_fault_resume(pipe->bcast_mmu);
270 	else {
271 		int i;
272 
273 		for (i = 0; i < pipe->num_mmu; i++)
274 			lima_mmu_page_fault_resume(pipe->mmu[i]);
275 	}
276 
277 	if (pipe->current_vm)
278 		lima_vm_put(pipe->current_vm);
279 
280 	pipe->current_vm = NULL;
281 	pipe->current_task = NULL;
282 
283 	drm_sched_resubmit_jobs(&pipe->base);
284 	drm_sched_start(&pipe->base, true);
285 }
286 
287 static void lima_sched_timedout_job(struct drm_sched_job *job)
288 {
289 	struct lima_sched_pipe *pipe = to_lima_pipe(job->sched);
290 	struct lima_sched_task *task = to_lima_task(job);
291 
292 	DRM_ERROR("lima job timeout\n");
293 
294 	lima_sched_handle_error_task(pipe, task);
295 }
296 
297 static void lima_sched_free_job(struct drm_sched_job *job)
298 {
299 	struct lima_sched_task *task = to_lima_task(job);
300 	struct lima_sched_pipe *pipe = to_lima_pipe(job->sched);
301 	struct lima_vm *vm = task->vm;
302 	struct lima_bo **bos = task->bos;
303 	int i;
304 
305 	dma_fence_put(task->fence);
306 
307 	for (i = 0; i < task->num_bos; i++)
308 		lima_vm_bo_del(vm, bos[i]);
309 
310 	lima_sched_task_fini(task);
311 	kmem_cache_free(pipe->task_slab, task);
312 }
313 
314 static const struct drm_sched_backend_ops lima_sched_ops = {
315 	.dependency = lima_sched_dependency,
316 	.run_job = lima_sched_run_job,
317 	.timedout_job = lima_sched_timedout_job,
318 	.free_job = lima_sched_free_job,
319 };
320 
321 static void lima_sched_error_work(struct work_struct *work)
322 {
323 	struct lima_sched_pipe *pipe =
324 		container_of(work, struct lima_sched_pipe, error_work);
325 	struct lima_sched_task *task = pipe->current_task;
326 
327 	lima_sched_handle_error_task(pipe, task);
328 }
329 
330 int lima_sched_pipe_init(struct lima_sched_pipe *pipe, const char *name)
331 {
332 	unsigned int timeout = lima_sched_timeout_ms > 0 ?
333 			       lima_sched_timeout_ms : 500;
334 
335 	pipe->fence_context = dma_fence_context_alloc(1);
336 	spin_lock_init(&pipe->fence_lock);
337 
338 	INIT_WORK(&pipe->error_work, lima_sched_error_work);
339 
340 	return drm_sched_init(&pipe->base, &lima_sched_ops, 1, 0,
341 			      msecs_to_jiffies(timeout), name);
342 }
343 
344 void lima_sched_pipe_fini(struct lima_sched_pipe *pipe)
345 {
346 	drm_sched_fini(&pipe->base);
347 }
348 
349 void lima_sched_pipe_task_done(struct lima_sched_pipe *pipe)
350 {
351 	if (pipe->error)
352 		schedule_work(&pipe->error_work);
353 	else {
354 		struct lima_sched_task *task = pipe->current_task;
355 
356 		pipe->task_fini(pipe);
357 		dma_fence_signal(task->fence);
358 	}
359 }
360