xref: /openbmc/linux/drivers/gpu/drm/vc4/vc4_irq.c (revision 63705da3)
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 <linux/platform_device.h>
49 
50 #include <drm/drm_drv.h>
51 
52 #include "vc4_drv.h"
53 #include "vc4_regs.h"
54 
55 #define V3D_DRIVER_IRQS (V3D_INT_OUTOMEM | \
56 			 V3D_INT_FLDONE | \
57 			 V3D_INT_FRDONE)
58 
59 DECLARE_WAIT_QUEUE_HEAD(render_wait);
60 
61 static void
62 vc4_overflow_mem_work(struct work_struct *work)
63 {
64 	struct vc4_dev *vc4 =
65 		container_of(work, struct vc4_dev, overflow_mem_work);
66 	struct vc4_bo *bo;
67 	int bin_bo_slot;
68 	struct vc4_exec_info *exec;
69 	unsigned long irqflags;
70 
71 	mutex_lock(&vc4->bin_bo_lock);
72 
73 	if (!vc4->bin_bo)
74 		goto complete;
75 
76 	bo = vc4->bin_bo;
77 
78 	bin_bo_slot = vc4_v3d_get_bin_slot(vc4);
79 	if (bin_bo_slot < 0) {
80 		DRM_ERROR("Couldn't allocate binner overflow mem\n");
81 		goto complete;
82 	}
83 
84 	spin_lock_irqsave(&vc4->job_lock, irqflags);
85 
86 	if (vc4->bin_alloc_overflow) {
87 		/* If we had overflow memory allocated previously,
88 		 * then that chunk will free when the current bin job
89 		 * is done.  If we don't have a bin job running, then
90 		 * the chunk will be done whenever the list of render
91 		 * jobs has drained.
92 		 */
93 		exec = vc4_first_bin_job(vc4);
94 		if (!exec)
95 			exec = vc4_last_render_job(vc4);
96 		if (exec) {
97 			exec->bin_slots |= vc4->bin_alloc_overflow;
98 		} else {
99 			/* There's nothing queued in the hardware, so
100 			 * the old slot is free immediately.
101 			 */
102 			vc4->bin_alloc_used &= ~vc4->bin_alloc_overflow;
103 		}
104 	}
105 	vc4->bin_alloc_overflow = BIT(bin_bo_slot);
106 
107 	V3D_WRITE(V3D_BPOA, bo->base.paddr + bin_bo_slot * vc4->bin_alloc_size);
108 	V3D_WRITE(V3D_BPOS, bo->base.base.size);
109 	V3D_WRITE(V3D_INTCTL, V3D_INT_OUTOMEM);
110 	V3D_WRITE(V3D_INTENA, V3D_INT_OUTOMEM);
111 	spin_unlock_irqrestore(&vc4->job_lock, irqflags);
112 
113 complete:
114 	mutex_unlock(&vc4->bin_bo_lock);
115 }
116 
117 static void
118 vc4_irq_finish_bin_job(struct drm_device *dev)
119 {
120 	struct vc4_dev *vc4 = to_vc4_dev(dev);
121 	struct vc4_exec_info *next, *exec = vc4_first_bin_job(vc4);
122 
123 	if (!exec)
124 		return;
125 
126 	vc4_move_job_to_render(dev, exec);
127 	next = vc4_first_bin_job(vc4);
128 
129 	/* Only submit the next job in the bin list if it matches the perfmon
130 	 * attached to the one that just finished (or if both jobs don't have
131 	 * perfmon attached to them).
132 	 */
133 	if (next && next->perfmon == exec->perfmon)
134 		vc4_submit_next_bin_job(dev);
135 }
136 
137 static void
138 vc4_cancel_bin_job(struct drm_device *dev)
139 {
140 	struct vc4_dev *vc4 = to_vc4_dev(dev);
141 	struct vc4_exec_info *exec = vc4_first_bin_job(vc4);
142 
143 	if (!exec)
144 		return;
145 
146 	/* Stop the perfmon so that the next bin job can be started. */
147 	if (exec->perfmon)
148 		vc4_perfmon_stop(vc4, exec->perfmon, false);
149 
150 	list_move_tail(&exec->head, &vc4->bin_job_list);
151 	vc4_submit_next_bin_job(dev);
152 }
153 
154 static void
155 vc4_irq_finish_render_job(struct drm_device *dev)
156 {
157 	struct vc4_dev *vc4 = to_vc4_dev(dev);
158 	struct vc4_exec_info *exec = vc4_first_render_job(vc4);
159 	struct vc4_exec_info *nextbin, *nextrender;
160 
161 	if (!exec)
162 		return;
163 
164 	vc4->finished_seqno++;
165 	list_move_tail(&exec->head, &vc4->job_done_list);
166 
167 	nextbin = vc4_first_bin_job(vc4);
168 	nextrender = vc4_first_render_job(vc4);
169 
170 	/* Only stop the perfmon if following jobs in the queue don't expect it
171 	 * to be enabled.
172 	 */
173 	if (exec->perfmon && !nextrender &&
174 	    (!nextbin || nextbin->perfmon != exec->perfmon))
175 		vc4_perfmon_stop(vc4, exec->perfmon, true);
176 
177 	/* If there's a render job waiting, start it. If this is not the case
178 	 * we may have to unblock the binner if it's been stalled because of
179 	 * perfmon (this can be checked by comparing the perfmon attached to
180 	 * the finished renderjob to the one attached to the next bin job: if
181 	 * they don't match, this means the binner is stalled and should be
182 	 * restarted).
183 	 */
184 	if (nextrender)
185 		vc4_submit_next_render_job(dev);
186 	else if (nextbin && nextbin->perfmon != exec->perfmon)
187 		vc4_submit_next_bin_job(dev);
188 
189 	if (exec->fence) {
190 		dma_fence_signal_locked(exec->fence);
191 		dma_fence_put(exec->fence);
192 		exec->fence = NULL;
193 	}
194 
195 	wake_up_all(&vc4->job_wait_queue);
196 	schedule_work(&vc4->job_done_work);
197 }
198 
199 static irqreturn_t
200 vc4_irq(int irq, void *arg)
201 {
202 	struct drm_device *dev = arg;
203 	struct vc4_dev *vc4 = to_vc4_dev(dev);
204 	uint32_t intctl;
205 	irqreturn_t status = IRQ_NONE;
206 
207 	barrier();
208 	intctl = V3D_READ(V3D_INTCTL);
209 
210 	/* Acknowledge the interrupts we're handling here. The binner
211 	 * last flush / render frame done interrupt will be cleared,
212 	 * while OUTOMEM will stay high until the underlying cause is
213 	 * cleared.
214 	 */
215 	V3D_WRITE(V3D_INTCTL, intctl);
216 
217 	if (intctl & V3D_INT_OUTOMEM) {
218 		/* Disable OUTOMEM until the work is done. */
219 		V3D_WRITE(V3D_INTDIS, V3D_INT_OUTOMEM);
220 		schedule_work(&vc4->overflow_mem_work);
221 		status = IRQ_HANDLED;
222 	}
223 
224 	if (intctl & V3D_INT_FLDONE) {
225 		spin_lock(&vc4->job_lock);
226 		vc4_irq_finish_bin_job(dev);
227 		spin_unlock(&vc4->job_lock);
228 		status = IRQ_HANDLED;
229 	}
230 
231 	if (intctl & V3D_INT_FRDONE) {
232 		spin_lock(&vc4->job_lock);
233 		vc4_irq_finish_render_job(dev);
234 		spin_unlock(&vc4->job_lock);
235 		status = IRQ_HANDLED;
236 	}
237 
238 	return status;
239 }
240 
241 static void
242 vc4_irq_prepare(struct drm_device *dev)
243 {
244 	struct vc4_dev *vc4 = to_vc4_dev(dev);
245 
246 	if (!vc4->v3d)
247 		return;
248 
249 	init_waitqueue_head(&vc4->job_wait_queue);
250 	INIT_WORK(&vc4->overflow_mem_work, vc4_overflow_mem_work);
251 
252 	/* Clear any pending interrupts someone might have left around
253 	 * for us.
254 	 */
255 	V3D_WRITE(V3D_INTCTL, V3D_DRIVER_IRQS);
256 }
257 
258 void
259 vc4_irq_enable(struct drm_device *dev)
260 {
261 	struct vc4_dev *vc4 = to_vc4_dev(dev);
262 
263 	if (!vc4->v3d)
264 		return;
265 
266 	/* Enable the render done interrupts. The out-of-memory interrupt is
267 	 * enabled as soon as we have a binner BO allocated.
268 	 */
269 	V3D_WRITE(V3D_INTENA, V3D_INT_FLDONE | V3D_INT_FRDONE);
270 }
271 
272 void
273 vc4_irq_disable(struct drm_device *dev)
274 {
275 	struct vc4_dev *vc4 = to_vc4_dev(dev);
276 
277 	if (!vc4->v3d)
278 		return;
279 
280 	/* Disable sending interrupts for our driver's IRQs. */
281 	V3D_WRITE(V3D_INTDIS, V3D_DRIVER_IRQS);
282 
283 	/* Clear any pending interrupts we might have left. */
284 	V3D_WRITE(V3D_INTCTL, V3D_DRIVER_IRQS);
285 
286 	/* Finish any interrupt handler still in flight. */
287 	disable_irq(vc4->irq);
288 
289 	cancel_work_sync(&vc4->overflow_mem_work);
290 }
291 
292 int vc4_irq_install(struct drm_device *dev, int irq)
293 {
294 	int ret;
295 
296 	if (irq == IRQ_NOTCONNECTED)
297 		return -ENOTCONN;
298 
299 	vc4_irq_prepare(dev);
300 
301 	ret = request_irq(irq, vc4_irq, 0, dev->driver->name, dev);
302 	if (ret)
303 		return ret;
304 
305 	vc4_irq_enable(dev);
306 
307 	return 0;
308 }
309 
310 void vc4_irq_uninstall(struct drm_device *dev)
311 {
312 	struct vc4_dev *vc4 = to_vc4_dev(dev);
313 
314 	vc4_irq_disable(dev);
315 	free_irq(vc4->irq, dev);
316 }
317 
318 /** Reinitializes interrupt registers when a GPU reset is performed. */
319 void vc4_irq_reset(struct drm_device *dev)
320 {
321 	struct vc4_dev *vc4 = to_vc4_dev(dev);
322 	unsigned long irqflags;
323 
324 	/* Acknowledge any stale IRQs. */
325 	V3D_WRITE(V3D_INTCTL, V3D_DRIVER_IRQS);
326 
327 	/*
328 	 * Turn all our interrupts on.  Binner out of memory is the
329 	 * only one we expect to trigger at this point, since we've
330 	 * just come from poweron and haven't supplied any overflow
331 	 * memory yet.
332 	 */
333 	V3D_WRITE(V3D_INTENA, V3D_DRIVER_IRQS);
334 
335 	spin_lock_irqsave(&vc4->job_lock, irqflags);
336 	vc4_cancel_bin_job(dev);
337 	vc4_irq_finish_render_job(dev);
338 	spin_unlock_irqrestore(&vc4->job_lock, irqflags);
339 }
340