xref: /openbmc/linux/drivers/gpu/drm/vc4/vc4_irq.c (revision fb574682)
1 /*
2  * Copyright © 2014 Broadcom
3  *
4  * Permission is hereby granted, free of charge, to any person obtaining a
5  * copy of this software and associated documentation files (the "Software"),
6  * to deal in the Software without restriction, including without limitation
7  * the rights to use, copy, modify, merge, publish, distribute, sublicense,
8  * and/or sell copies of the Software, and to permit persons to whom the
9  * Software is furnished to do so, subject to the following conditions:
10  *
11  * The above copyright notice and this permission notice (including the next
12  * paragraph) shall be included in all copies or substantial portions of the
13  * Software.
14  *
15  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
16  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
17  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
18  * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
19  * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
20  * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS
21  * IN THE SOFTWARE.
22  */
23 
24 /**
25  * DOC: Interrupt management for the V3D engine
26  *
27  * We have an interrupt status register (V3D_INTCTL) which reports
28  * interrupts, and where writing 1 bits clears those interrupts.
29  * There are also a pair of interrupt registers
30  * (V3D_INTENA/V3D_INTDIS) where writing a 1 to their bits enables or
31  * disables that specific interrupt, and 0s written are ignored
32  * (reading either one returns the set of enabled interrupts).
33  *
34  * When we take a binning flush done interrupt, we need to submit the
35  * next frame for binning and move the finished frame to the render
36  * thread.
37  *
38  * When we take a render frame interrupt, we need to wake the
39  * processes waiting for some frame to be done, and get the next frame
40  * submitted ASAP (so the hardware doesn't sit idle when there's work
41  * to do).
42  *
43  * When we take the binner out of memory interrupt, we need to
44  * allocate some new memory and pass it to the binner so that the
45  * current job can make progress.
46  */
47 
48 #include "vc4_drv.h"
49 #include "vc4_regs.h"
50 
51 #define V3D_DRIVER_IRQS (V3D_INT_OUTOMEM | \
52 			 V3D_INT_FLDONE | \
53 			 V3D_INT_FRDONE)
54 
55 DECLARE_WAIT_QUEUE_HEAD(render_wait);
56 
57 static void
58 vc4_overflow_mem_work(struct work_struct *work)
59 {
60 	struct vc4_dev *vc4 =
61 		container_of(work, struct vc4_dev, overflow_mem_work);
62 	struct vc4_bo *bo;
63 	int bin_bo_slot;
64 	struct vc4_exec_info *exec;
65 	unsigned long irqflags;
66 
67 	mutex_lock(&vc4->bin_bo_lock);
68 
69 	if (!vc4->bin_bo)
70 		goto complete;
71 
72 	bo = vc4->bin_bo;
73 
74 	bin_bo_slot = vc4_v3d_get_bin_slot(vc4);
75 	if (bin_bo_slot < 0) {
76 		DRM_ERROR("Couldn't allocate binner overflow mem\n");
77 		goto complete;
78 	}
79 
80 	spin_lock_irqsave(&vc4->job_lock, irqflags);
81 
82 	if (vc4->bin_alloc_overflow) {
83 		/* If we had overflow memory allocated previously,
84 		 * then that chunk will free when the current bin job
85 		 * is done.  If we don't have a bin job running, then
86 		 * the chunk will be done whenever the list of render
87 		 * jobs has drained.
88 		 */
89 		exec = vc4_first_bin_job(vc4);
90 		if (!exec)
91 			exec = vc4_last_render_job(vc4);
92 		if (exec) {
93 			exec->bin_slots |= vc4->bin_alloc_overflow;
94 		} else {
95 			/* There's nothing queued in the hardware, so
96 			 * the old slot is free immediately.
97 			 */
98 			vc4->bin_alloc_used &= ~vc4->bin_alloc_overflow;
99 		}
100 	}
101 	vc4->bin_alloc_overflow = BIT(bin_bo_slot);
102 
103 	V3D_WRITE(V3D_BPOA, bo->base.paddr + bin_bo_slot * vc4->bin_alloc_size);
104 	V3D_WRITE(V3D_BPOS, bo->base.base.size);
105 	V3D_WRITE(V3D_INTCTL, V3D_INT_OUTOMEM);
106 	V3D_WRITE(V3D_INTENA, V3D_INT_OUTOMEM);
107 	spin_unlock_irqrestore(&vc4->job_lock, irqflags);
108 
109 complete:
110 	mutex_unlock(&vc4->bin_bo_lock);
111 }
112 
113 static void
114 vc4_irq_finish_bin_job(struct drm_device *dev)
115 {
116 	struct vc4_dev *vc4 = to_vc4_dev(dev);
117 	struct vc4_exec_info *next, *exec = vc4_first_bin_job(vc4);
118 
119 	if (!exec)
120 		return;
121 
122 	vc4_move_job_to_render(dev, exec);
123 	next = vc4_first_bin_job(vc4);
124 
125 	/* Only submit the next job in the bin list if it matches the perfmon
126 	 * attached to the one that just finished (or if both jobs don't have
127 	 * perfmon attached to them).
128 	 */
129 	if (next && next->perfmon == exec->perfmon)
130 		vc4_submit_next_bin_job(dev);
131 }
132 
133 static void
134 vc4_cancel_bin_job(struct drm_device *dev)
135 {
136 	struct vc4_dev *vc4 = to_vc4_dev(dev);
137 	struct vc4_exec_info *exec = vc4_first_bin_job(vc4);
138 
139 	if (!exec)
140 		return;
141 
142 	/* Stop the perfmon so that the next bin job can be started. */
143 	if (exec->perfmon)
144 		vc4_perfmon_stop(vc4, exec->perfmon, false);
145 
146 	list_move_tail(&exec->head, &vc4->bin_job_list);
147 	vc4_submit_next_bin_job(dev);
148 }
149 
150 static void
151 vc4_irq_finish_render_job(struct drm_device *dev)
152 {
153 	struct vc4_dev *vc4 = to_vc4_dev(dev);
154 	struct vc4_exec_info *exec = vc4_first_render_job(vc4);
155 	struct vc4_exec_info *nextbin, *nextrender;
156 
157 	if (!exec)
158 		return;
159 
160 	vc4->finished_seqno++;
161 	list_move_tail(&exec->head, &vc4->job_done_list);
162 
163 	nextbin = vc4_first_bin_job(vc4);
164 	nextrender = vc4_first_render_job(vc4);
165 
166 	/* Only stop the perfmon if following jobs in the queue don't expect it
167 	 * to be enabled.
168 	 */
169 	if (exec->perfmon && !nextrender &&
170 	    (!nextbin || nextbin->perfmon != exec->perfmon))
171 		vc4_perfmon_stop(vc4, exec->perfmon, true);
172 
173 	/* If there's a render job waiting, start it. If this is not the case
174 	 * we may have to unblock the binner if it's been stalled because of
175 	 * perfmon (this can be checked by comparing the perfmon attached to
176 	 * the finished renderjob to the one attached to the next bin job: if
177 	 * they don't match, this means the binner is stalled and should be
178 	 * restarted).
179 	 */
180 	if (nextrender)
181 		vc4_submit_next_render_job(dev);
182 	else if (nextbin && nextbin->perfmon != exec->perfmon)
183 		vc4_submit_next_bin_job(dev);
184 
185 	if (exec->fence) {
186 		dma_fence_signal_locked(exec->fence);
187 		dma_fence_put(exec->fence);
188 		exec->fence = NULL;
189 	}
190 
191 	wake_up_all(&vc4->job_wait_queue);
192 	schedule_work(&vc4->job_done_work);
193 }
194 
195 irqreturn_t
196 vc4_irq(int irq, void *arg)
197 {
198 	struct drm_device *dev = arg;
199 	struct vc4_dev *vc4 = to_vc4_dev(dev);
200 	uint32_t intctl;
201 	irqreturn_t status = IRQ_NONE;
202 
203 	barrier();
204 	intctl = V3D_READ(V3D_INTCTL);
205 
206 	/* Acknowledge the interrupts we're handling here. The binner
207 	 * last flush / render frame done interrupt will be cleared,
208 	 * while OUTOMEM will stay high until the underlying cause is
209 	 * cleared.
210 	 */
211 	V3D_WRITE(V3D_INTCTL, intctl);
212 
213 	if (intctl & V3D_INT_OUTOMEM) {
214 		/* Disable OUTOMEM until the work is done. */
215 		V3D_WRITE(V3D_INTDIS, V3D_INT_OUTOMEM);
216 		schedule_work(&vc4->overflow_mem_work);
217 		status = IRQ_HANDLED;
218 	}
219 
220 	if (intctl & V3D_INT_FLDONE) {
221 		spin_lock(&vc4->job_lock);
222 		vc4_irq_finish_bin_job(dev);
223 		spin_unlock(&vc4->job_lock);
224 		status = IRQ_HANDLED;
225 	}
226 
227 	if (intctl & V3D_INT_FRDONE) {
228 		spin_lock(&vc4->job_lock);
229 		vc4_irq_finish_render_job(dev);
230 		spin_unlock(&vc4->job_lock);
231 		status = IRQ_HANDLED;
232 	}
233 
234 	return status;
235 }
236 
237 void
238 vc4_irq_preinstall(struct drm_device *dev)
239 {
240 	struct vc4_dev *vc4 = to_vc4_dev(dev);
241 
242 	if (!vc4->v3d)
243 		return;
244 
245 	init_waitqueue_head(&vc4->job_wait_queue);
246 	INIT_WORK(&vc4->overflow_mem_work, vc4_overflow_mem_work);
247 
248 	/* Clear any pending interrupts someone might have left around
249 	 * for us.
250 	 */
251 	V3D_WRITE(V3D_INTCTL, V3D_DRIVER_IRQS);
252 }
253 
254 int
255 vc4_irq_postinstall(struct drm_device *dev)
256 {
257 	struct vc4_dev *vc4 = to_vc4_dev(dev);
258 
259 	if (!vc4->v3d)
260 		return 0;
261 
262 	/* Enable the render done interrupts. The out-of-memory interrupt is
263 	 * enabled as soon as we have a binner BO allocated.
264 	 */
265 	V3D_WRITE(V3D_INTENA, V3D_INT_FLDONE | V3D_INT_FRDONE);
266 
267 	return 0;
268 }
269 
270 void
271 vc4_irq_uninstall(struct drm_device *dev)
272 {
273 	struct vc4_dev *vc4 = to_vc4_dev(dev);
274 
275 	if (!vc4->v3d)
276 		return;
277 
278 	/* Disable sending interrupts for our driver's IRQs. */
279 	V3D_WRITE(V3D_INTDIS, V3D_DRIVER_IRQS);
280 
281 	/* Clear any pending interrupts we might have left. */
282 	V3D_WRITE(V3D_INTCTL, V3D_DRIVER_IRQS);
283 
284 	/* Finish any interrupt handler still in flight. */
285 	disable_irq(dev->irq);
286 
287 	cancel_work_sync(&vc4->overflow_mem_work);
288 }
289 
290 /** Reinitializes interrupt registers when a GPU reset is performed. */
291 void vc4_irq_reset(struct drm_device *dev)
292 {
293 	struct vc4_dev *vc4 = to_vc4_dev(dev);
294 	unsigned long irqflags;
295 
296 	/* Acknowledge any stale IRQs. */
297 	V3D_WRITE(V3D_INTCTL, V3D_DRIVER_IRQS);
298 
299 	/*
300 	 * Turn all our interrupts on.  Binner out of memory is the
301 	 * only one we expect to trigger at this point, since we've
302 	 * just come from poweron and haven't supplied any overflow
303 	 * memory yet.
304 	 */
305 	V3D_WRITE(V3D_INTENA, V3D_DRIVER_IRQS);
306 
307 	spin_lock_irqsave(&vc4->job_lock, irqflags);
308 	vc4_cancel_bin_job(dev);
309 	vc4_irq_finish_render_job(dev);
310 	spin_unlock_irqrestore(&vc4->job_lock, irqflags);
311 }
312