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 #include "vc4_trace.h"
55
56 #define V3D_DRIVER_IRQS (V3D_INT_OUTOMEM | \
57 V3D_INT_FLDONE | \
58 V3D_INT_FRDONE)
59
60 static void
vc4_overflow_mem_work(struct work_struct * work)61 vc4_overflow_mem_work(struct work_struct *work)
62 {
63 struct vc4_dev *vc4 =
64 container_of(work, struct vc4_dev, overflow_mem_work);
65 struct vc4_bo *bo;
66 int bin_bo_slot;
67 struct vc4_exec_info *exec;
68 unsigned long irqflags;
69
70 mutex_lock(&vc4->bin_bo_lock);
71
72 if (!vc4->bin_bo)
73 goto complete;
74
75 bo = vc4->bin_bo;
76
77 bin_bo_slot = vc4_v3d_get_bin_slot(vc4);
78 if (bin_bo_slot < 0) {
79 drm_err(&vc4->base, "Couldn't allocate binner overflow mem\n");
80 goto complete;
81 }
82
83 spin_lock_irqsave(&vc4->job_lock, irqflags);
84
85 if (vc4->bin_alloc_overflow) {
86 /* If we had overflow memory allocated previously,
87 * then that chunk will free when the current bin job
88 * is done. If we don't have a bin job running, then
89 * the chunk will be done whenever the list of render
90 * jobs has drained.
91 */
92 exec = vc4_first_bin_job(vc4);
93 if (!exec)
94 exec = vc4_last_render_job(vc4);
95 if (exec) {
96 exec->bin_slots |= vc4->bin_alloc_overflow;
97 } else {
98 /* There's nothing queued in the hardware, so
99 * the old slot is free immediately.
100 */
101 vc4->bin_alloc_used &= ~vc4->bin_alloc_overflow;
102 }
103 }
104 vc4->bin_alloc_overflow = BIT(bin_bo_slot);
105
106 V3D_WRITE(V3D_BPOA, bo->base.dma_addr + bin_bo_slot * vc4->bin_alloc_size);
107 V3D_WRITE(V3D_BPOS, bo->base.base.size);
108 V3D_WRITE(V3D_INTCTL, V3D_INT_OUTOMEM);
109 V3D_WRITE(V3D_INTENA, V3D_INT_OUTOMEM);
110 spin_unlock_irqrestore(&vc4->job_lock, irqflags);
111
112 complete:
113 mutex_unlock(&vc4->bin_bo_lock);
114 }
115
116 static void
vc4_irq_finish_bin_job(struct drm_device * dev)117 vc4_irq_finish_bin_job(struct drm_device *dev)
118 {
119 struct vc4_dev *vc4 = to_vc4_dev(dev);
120 struct vc4_exec_info *next, *exec = vc4_first_bin_job(vc4);
121
122 if (!exec)
123 return;
124
125 trace_vc4_bcl_end_irq(dev, exec->seqno);
126
127 vc4_move_job_to_render(dev, exec);
128 next = vc4_first_bin_job(vc4);
129
130 /* Only submit the next job in the bin list if it matches the perfmon
131 * attached to the one that just finished (or if both jobs don't have
132 * perfmon attached to them).
133 */
134 if (next && next->perfmon == exec->perfmon)
135 vc4_submit_next_bin_job(dev);
136 }
137
138 static void
vc4_cancel_bin_job(struct drm_device * dev)139 vc4_cancel_bin_job(struct drm_device *dev)
140 {
141 struct vc4_dev *vc4 = to_vc4_dev(dev);
142 struct vc4_exec_info *exec = vc4_first_bin_job(vc4);
143
144 if (!exec)
145 return;
146
147 /* Stop the perfmon so that the next bin job can be started. */
148 if (exec->perfmon)
149 vc4_perfmon_stop(vc4, exec->perfmon, false);
150
151 list_move_tail(&exec->head, &vc4->bin_job_list);
152 vc4_submit_next_bin_job(dev);
153 }
154
155 static void
vc4_irq_finish_render_job(struct drm_device * dev)156 vc4_irq_finish_render_job(struct drm_device *dev)
157 {
158 struct vc4_dev *vc4 = to_vc4_dev(dev);
159 struct vc4_exec_info *exec = vc4_first_render_job(vc4);
160 struct vc4_exec_info *nextbin, *nextrender;
161
162 if (!exec)
163 return;
164
165 trace_vc4_rcl_end_irq(dev, exec->seqno);
166
167 vc4->finished_seqno++;
168 list_move_tail(&exec->head, &vc4->job_done_list);
169
170 nextbin = vc4_first_bin_job(vc4);
171 nextrender = vc4_first_render_job(vc4);
172
173 /* Only stop the perfmon if following jobs in the queue don't expect it
174 * to be enabled.
175 */
176 if (exec->perfmon && !nextrender &&
177 (!nextbin || nextbin->perfmon != exec->perfmon))
178 vc4_perfmon_stop(vc4, exec->perfmon, true);
179
180 /* If there's a render job waiting, start it. If this is not the case
181 * we may have to unblock the binner if it's been stalled because of
182 * perfmon (this can be checked by comparing the perfmon attached to
183 * the finished renderjob to the one attached to the next bin job: if
184 * they don't match, this means the binner is stalled and should be
185 * restarted).
186 */
187 if (nextrender)
188 vc4_submit_next_render_job(dev);
189 else if (nextbin && nextbin->perfmon != exec->perfmon)
190 vc4_submit_next_bin_job(dev);
191
192 if (exec->fence) {
193 dma_fence_signal_locked(exec->fence);
194 dma_fence_put(exec->fence);
195 exec->fence = NULL;
196 }
197
198 wake_up_all(&vc4->job_wait_queue);
199 schedule_work(&vc4->job_done_work);
200 }
201
202 static irqreturn_t
vc4_irq(int irq,void * arg)203 vc4_irq(int irq, void *arg)
204 {
205 struct drm_device *dev = arg;
206 struct vc4_dev *vc4 = to_vc4_dev(dev);
207 uint32_t intctl;
208 irqreturn_t status = IRQ_NONE;
209
210 barrier();
211 intctl = V3D_READ(V3D_INTCTL);
212
213 /* Acknowledge the interrupts we're handling here. The binner
214 * last flush / render frame done interrupt will be cleared,
215 * while OUTOMEM will stay high until the underlying cause is
216 * cleared.
217 */
218 V3D_WRITE(V3D_INTCTL, intctl);
219
220 if (intctl & V3D_INT_OUTOMEM) {
221 /* Disable OUTOMEM until the work is done. */
222 V3D_WRITE(V3D_INTDIS, V3D_INT_OUTOMEM);
223 schedule_work(&vc4->overflow_mem_work);
224 status = IRQ_HANDLED;
225 }
226
227 if (intctl & V3D_INT_FLDONE) {
228 spin_lock(&vc4->job_lock);
229 vc4_irq_finish_bin_job(dev);
230 spin_unlock(&vc4->job_lock);
231 status = IRQ_HANDLED;
232 }
233
234 if (intctl & V3D_INT_FRDONE) {
235 spin_lock(&vc4->job_lock);
236 vc4_irq_finish_render_job(dev);
237 spin_unlock(&vc4->job_lock);
238 status = IRQ_HANDLED;
239 }
240
241 return status;
242 }
243
244 static void
vc4_irq_prepare(struct drm_device * dev)245 vc4_irq_prepare(struct drm_device *dev)
246 {
247 struct vc4_dev *vc4 = to_vc4_dev(dev);
248
249 if (!vc4->v3d)
250 return;
251
252 init_waitqueue_head(&vc4->job_wait_queue);
253 INIT_WORK(&vc4->overflow_mem_work, vc4_overflow_mem_work);
254
255 /* Clear any pending interrupts someone might have left around
256 * for us.
257 */
258 V3D_WRITE(V3D_INTCTL, V3D_DRIVER_IRQS);
259 }
260
261 void
vc4_irq_enable(struct drm_device * dev)262 vc4_irq_enable(struct drm_device *dev)
263 {
264 struct vc4_dev *vc4 = to_vc4_dev(dev);
265
266 if (WARN_ON_ONCE(vc4->gen > VC4_GEN_4))
267 return;
268
269 if (!vc4->v3d)
270 return;
271
272 /* Enable the render done interrupts. The out-of-memory interrupt is
273 * enabled as soon as we have a binner BO allocated.
274 */
275 V3D_WRITE(V3D_INTENA, V3D_INT_FLDONE | V3D_INT_FRDONE);
276 }
277
278 void
vc4_irq_disable(struct drm_device * dev)279 vc4_irq_disable(struct drm_device *dev)
280 {
281 struct vc4_dev *vc4 = to_vc4_dev(dev);
282
283 if (WARN_ON_ONCE(vc4->gen > VC4_GEN_4))
284 return;
285
286 if (!vc4->v3d)
287 return;
288
289 /* Disable sending interrupts for our driver's IRQs. */
290 V3D_WRITE(V3D_INTDIS, V3D_DRIVER_IRQS);
291
292 /* Clear any pending interrupts we might have left. */
293 V3D_WRITE(V3D_INTCTL, V3D_DRIVER_IRQS);
294
295 /* Finish any interrupt handler still in flight. */
296 synchronize_irq(vc4->irq);
297
298 cancel_work_sync(&vc4->overflow_mem_work);
299 }
300
vc4_irq_install(struct drm_device * dev,int irq)301 int vc4_irq_install(struct drm_device *dev, int irq)
302 {
303 struct vc4_dev *vc4 = to_vc4_dev(dev);
304 int ret;
305
306 if (WARN_ON_ONCE(vc4->gen > VC4_GEN_4))
307 return -ENODEV;
308
309 if (irq == IRQ_NOTCONNECTED)
310 return -ENOTCONN;
311
312 vc4_irq_prepare(dev);
313
314 ret = request_irq(irq, vc4_irq, 0, dev->driver->name, dev);
315 if (ret)
316 return ret;
317
318 vc4_irq_enable(dev);
319
320 return 0;
321 }
322
vc4_irq_uninstall(struct drm_device * dev)323 void vc4_irq_uninstall(struct drm_device *dev)
324 {
325 struct vc4_dev *vc4 = to_vc4_dev(dev);
326
327 if (WARN_ON_ONCE(vc4->gen > VC4_GEN_4))
328 return;
329
330 vc4_irq_disable(dev);
331 free_irq(vc4->irq, dev);
332 }
333
334 /** Reinitializes interrupt registers when a GPU reset is performed. */
vc4_irq_reset(struct drm_device * dev)335 void vc4_irq_reset(struct drm_device *dev)
336 {
337 struct vc4_dev *vc4 = to_vc4_dev(dev);
338 unsigned long irqflags;
339
340 if (WARN_ON_ONCE(vc4->gen > VC4_GEN_4))
341 return;
342
343 /* Acknowledge any stale IRQs. */
344 V3D_WRITE(V3D_INTCTL, V3D_DRIVER_IRQS);
345
346 /*
347 * Turn all our interrupts on. Binner out of memory is the
348 * only one we expect to trigger at this point, since we've
349 * just come from poweron and haven't supplied any overflow
350 * memory yet.
351 */
352 V3D_WRITE(V3D_INTENA, V3D_DRIVER_IRQS);
353
354 spin_lock_irqsave(&vc4->job_lock, irqflags);
355 vc4_cancel_bin_job(dev);
356 vc4_irq_finish_render_job(dev);
357 spin_unlock_irqrestore(&vc4->job_lock, irqflags);
358 }
359