xref: /openbmc/linux/drivers/gpu/drm/vc4/vc4_irq.c (revision 51c7b447)
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 = vc4->bin_bo;
63 	int bin_bo_slot;
64 	struct vc4_exec_info *exec;
65 	unsigned long irqflags;
66 
67 	bin_bo_slot = vc4_v3d_get_bin_slot(vc4);
68 	if (bin_bo_slot < 0) {
69 		DRM_ERROR("Couldn't allocate binner overflow mem\n");
70 		return;
71 	}
72 
73 	spin_lock_irqsave(&vc4->job_lock, irqflags);
74 
75 	if (vc4->bin_alloc_overflow) {
76 		/* If we had overflow memory allocated previously,
77 		 * then that chunk will free when the current bin job
78 		 * is done.  If we don't have a bin job running, then
79 		 * the chunk will be done whenever the list of render
80 		 * jobs has drained.
81 		 */
82 		exec = vc4_first_bin_job(vc4);
83 		if (!exec)
84 			exec = vc4_last_render_job(vc4);
85 		if (exec) {
86 			exec->bin_slots |= vc4->bin_alloc_overflow;
87 		} else {
88 			/* There's nothing queued in the hardware, so
89 			 * the old slot is free immediately.
90 			 */
91 			vc4->bin_alloc_used &= ~vc4->bin_alloc_overflow;
92 		}
93 	}
94 	vc4->bin_alloc_overflow = BIT(bin_bo_slot);
95 
96 	V3D_WRITE(V3D_BPOA, bo->base.paddr + bin_bo_slot * vc4->bin_alloc_size);
97 	V3D_WRITE(V3D_BPOS, bo->base.base.size);
98 	V3D_WRITE(V3D_INTCTL, V3D_INT_OUTOMEM);
99 	V3D_WRITE(V3D_INTENA, V3D_INT_OUTOMEM);
100 	spin_unlock_irqrestore(&vc4->job_lock, irqflags);
101 }
102 
103 static void
104 vc4_irq_finish_bin_job(struct drm_device *dev)
105 {
106 	struct vc4_dev *vc4 = to_vc4_dev(dev);
107 	struct vc4_exec_info *next, *exec = vc4_first_bin_job(vc4);
108 
109 	if (!exec)
110 		return;
111 
112 	vc4_move_job_to_render(dev, exec);
113 	next = vc4_first_bin_job(vc4);
114 
115 	/* Only submit the next job in the bin list if it matches the perfmon
116 	 * attached to the one that just finished (or if both jobs don't have
117 	 * perfmon attached to them).
118 	 */
119 	if (next && next->perfmon == exec->perfmon)
120 		vc4_submit_next_bin_job(dev);
121 }
122 
123 static void
124 vc4_cancel_bin_job(struct drm_device *dev)
125 {
126 	struct vc4_dev *vc4 = to_vc4_dev(dev);
127 	struct vc4_exec_info *exec = vc4_first_bin_job(vc4);
128 
129 	if (!exec)
130 		return;
131 
132 	/* Stop the perfmon so that the next bin job can be started. */
133 	if (exec->perfmon)
134 		vc4_perfmon_stop(vc4, exec->perfmon, false);
135 
136 	list_move_tail(&exec->head, &vc4->bin_job_list);
137 	vc4_submit_next_bin_job(dev);
138 }
139 
140 static void
141 vc4_irq_finish_render_job(struct drm_device *dev)
142 {
143 	struct vc4_dev *vc4 = to_vc4_dev(dev);
144 	struct vc4_exec_info *exec = vc4_first_render_job(vc4);
145 	struct vc4_exec_info *nextbin, *nextrender;
146 
147 	if (!exec)
148 		return;
149 
150 	vc4->finished_seqno++;
151 	list_move_tail(&exec->head, &vc4->job_done_list);
152 
153 	nextbin = vc4_first_bin_job(vc4);
154 	nextrender = vc4_first_render_job(vc4);
155 
156 	/* Only stop the perfmon if following jobs in the queue don't expect it
157 	 * to be enabled.
158 	 */
159 	if (exec->perfmon && !nextrender &&
160 	    (!nextbin || nextbin->perfmon != exec->perfmon))
161 		vc4_perfmon_stop(vc4, exec->perfmon, true);
162 
163 	/* If there's a render job waiting, start it. If this is not the case
164 	 * we may have to unblock the binner if it's been stalled because of
165 	 * perfmon (this can be checked by comparing the perfmon attached to
166 	 * the finished renderjob to the one attached to the next bin job: if
167 	 * they don't match, this means the binner is stalled and should be
168 	 * restarted).
169 	 */
170 	if (nextrender)
171 		vc4_submit_next_render_job(dev);
172 	else if (nextbin && nextbin->perfmon != exec->perfmon)
173 		vc4_submit_next_bin_job(dev);
174 
175 	if (exec->fence) {
176 		dma_fence_signal_locked(exec->fence);
177 		dma_fence_put(exec->fence);
178 		exec->fence = NULL;
179 	}
180 
181 	wake_up_all(&vc4->job_wait_queue);
182 	schedule_work(&vc4->job_done_work);
183 }
184 
185 irqreturn_t
186 vc4_irq(int irq, void *arg)
187 {
188 	struct drm_device *dev = arg;
189 	struct vc4_dev *vc4 = to_vc4_dev(dev);
190 	uint32_t intctl;
191 	irqreturn_t status = IRQ_NONE;
192 
193 	barrier();
194 	intctl = V3D_READ(V3D_INTCTL);
195 
196 	/* Acknowledge the interrupts we're handling here. The binner
197 	 * last flush / render frame done interrupt will be cleared,
198 	 * while OUTOMEM will stay high until the underlying cause is
199 	 * cleared.
200 	 */
201 	V3D_WRITE(V3D_INTCTL, intctl);
202 
203 	if (intctl & V3D_INT_OUTOMEM) {
204 		/* Disable OUTOMEM until the work is done. */
205 		V3D_WRITE(V3D_INTDIS, V3D_INT_OUTOMEM);
206 		schedule_work(&vc4->overflow_mem_work);
207 		status = IRQ_HANDLED;
208 	}
209 
210 	if (intctl & V3D_INT_FLDONE) {
211 		spin_lock(&vc4->job_lock);
212 		vc4_irq_finish_bin_job(dev);
213 		spin_unlock(&vc4->job_lock);
214 		status = IRQ_HANDLED;
215 	}
216 
217 	if (intctl & V3D_INT_FRDONE) {
218 		spin_lock(&vc4->job_lock);
219 		vc4_irq_finish_render_job(dev);
220 		spin_unlock(&vc4->job_lock);
221 		status = IRQ_HANDLED;
222 	}
223 
224 	return status;
225 }
226 
227 void
228 vc4_irq_preinstall(struct drm_device *dev)
229 {
230 	struct vc4_dev *vc4 = to_vc4_dev(dev);
231 
232 	if (!vc4->v3d)
233 		return;
234 
235 	init_waitqueue_head(&vc4->job_wait_queue);
236 	INIT_WORK(&vc4->overflow_mem_work, vc4_overflow_mem_work);
237 
238 	/* Clear any pending interrupts someone might have left around
239 	 * for us.
240 	 */
241 	V3D_WRITE(V3D_INTCTL, V3D_DRIVER_IRQS);
242 }
243 
244 int
245 vc4_irq_postinstall(struct drm_device *dev)
246 {
247 	struct vc4_dev *vc4 = to_vc4_dev(dev);
248 
249 	if (!vc4->v3d)
250 		return 0;
251 
252 	/* Enable both the render done and out of memory interrupts. */
253 	V3D_WRITE(V3D_INTENA, V3D_DRIVER_IRQS);
254 
255 	return 0;
256 }
257 
258 void
259 vc4_irq_uninstall(struct drm_device *dev)
260 {
261 	struct vc4_dev *vc4 = to_vc4_dev(dev);
262 
263 	if (!vc4->v3d)
264 		return;
265 
266 	/* Disable sending interrupts for our driver's IRQs. */
267 	V3D_WRITE(V3D_INTDIS, V3D_DRIVER_IRQS);
268 
269 	/* Clear any pending interrupts we might have left. */
270 	V3D_WRITE(V3D_INTCTL, V3D_DRIVER_IRQS);
271 
272 	/* Finish any interrupt handler still in flight. */
273 	disable_irq(dev->irq);
274 
275 	cancel_work_sync(&vc4->overflow_mem_work);
276 }
277 
278 /** Reinitializes interrupt registers when a GPU reset is performed. */
279 void vc4_irq_reset(struct drm_device *dev)
280 {
281 	struct vc4_dev *vc4 = to_vc4_dev(dev);
282 	unsigned long irqflags;
283 
284 	/* Acknowledge any stale IRQs. */
285 	V3D_WRITE(V3D_INTCTL, V3D_DRIVER_IRQS);
286 
287 	/*
288 	 * Turn all our interrupts on.  Binner out of memory is the
289 	 * only one we expect to trigger at this point, since we've
290 	 * just come from poweron and haven't supplied any overflow
291 	 * memory yet.
292 	 */
293 	V3D_WRITE(V3D_INTENA, V3D_DRIVER_IRQS);
294 
295 	spin_lock_irqsave(&vc4->job_lock, irqflags);
296 	vc4_cancel_bin_job(dev);
297 	vc4_irq_finish_render_job(dev);
298 	spin_unlock_irqrestore(&vc4->job_lock, irqflags);
299 }
300