xref: /openbmc/linux/drivers/gpu/drm/vc4/vc4_irq.c (revision 60772e48)
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 *exec = vc4_first_bin_job(vc4);
108 
109 	if (!exec)
110 		return;
111 
112 	vc4_move_job_to_render(dev, exec);
113 	vc4_submit_next_bin_job(dev);
114 }
115 
116 static void
117 vc4_cancel_bin_job(struct drm_device *dev)
118 {
119 	struct vc4_dev *vc4 = to_vc4_dev(dev);
120 	struct vc4_exec_info *exec = vc4_first_bin_job(vc4);
121 
122 	if (!exec)
123 		return;
124 
125 	list_move_tail(&exec->head, &vc4->bin_job_list);
126 	vc4_submit_next_bin_job(dev);
127 }
128 
129 static void
130 vc4_irq_finish_render_job(struct drm_device *dev)
131 {
132 	struct vc4_dev *vc4 = to_vc4_dev(dev);
133 	struct vc4_exec_info *exec = vc4_first_render_job(vc4);
134 
135 	if (!exec)
136 		return;
137 
138 	vc4->finished_seqno++;
139 	list_move_tail(&exec->head, &vc4->job_done_list);
140 	if (exec->fence) {
141 		dma_fence_signal_locked(exec->fence);
142 		dma_fence_put(exec->fence);
143 		exec->fence = NULL;
144 	}
145 	vc4_submit_next_render_job(dev);
146 
147 	wake_up_all(&vc4->job_wait_queue);
148 	schedule_work(&vc4->job_done_work);
149 }
150 
151 irqreturn_t
152 vc4_irq(int irq, void *arg)
153 {
154 	struct drm_device *dev = arg;
155 	struct vc4_dev *vc4 = to_vc4_dev(dev);
156 	uint32_t intctl;
157 	irqreturn_t status = IRQ_NONE;
158 
159 	barrier();
160 	intctl = V3D_READ(V3D_INTCTL);
161 
162 	/* Acknowledge the interrupts we're handling here. The binner
163 	 * last flush / render frame done interrupt will be cleared,
164 	 * while OUTOMEM will stay high until the underlying cause is
165 	 * cleared.
166 	 */
167 	V3D_WRITE(V3D_INTCTL, intctl);
168 
169 	if (intctl & V3D_INT_OUTOMEM) {
170 		/* Disable OUTOMEM until the work is done. */
171 		V3D_WRITE(V3D_INTDIS, V3D_INT_OUTOMEM);
172 		schedule_work(&vc4->overflow_mem_work);
173 		status = IRQ_HANDLED;
174 	}
175 
176 	if (intctl & V3D_INT_FLDONE) {
177 		spin_lock(&vc4->job_lock);
178 		vc4_irq_finish_bin_job(dev);
179 		spin_unlock(&vc4->job_lock);
180 		status = IRQ_HANDLED;
181 	}
182 
183 	if (intctl & V3D_INT_FRDONE) {
184 		spin_lock(&vc4->job_lock);
185 		vc4_irq_finish_render_job(dev);
186 		spin_unlock(&vc4->job_lock);
187 		status = IRQ_HANDLED;
188 	}
189 
190 	return status;
191 }
192 
193 void
194 vc4_irq_preinstall(struct drm_device *dev)
195 {
196 	struct vc4_dev *vc4 = to_vc4_dev(dev);
197 
198 	init_waitqueue_head(&vc4->job_wait_queue);
199 	INIT_WORK(&vc4->overflow_mem_work, vc4_overflow_mem_work);
200 
201 	/* Clear any pending interrupts someone might have left around
202 	 * for us.
203 	 */
204 	V3D_WRITE(V3D_INTCTL, V3D_DRIVER_IRQS);
205 }
206 
207 int
208 vc4_irq_postinstall(struct drm_device *dev)
209 {
210 	struct vc4_dev *vc4 = to_vc4_dev(dev);
211 
212 	/* Enable both the render done and out of memory interrupts. */
213 	V3D_WRITE(V3D_INTENA, V3D_DRIVER_IRQS);
214 
215 	return 0;
216 }
217 
218 void
219 vc4_irq_uninstall(struct drm_device *dev)
220 {
221 	struct vc4_dev *vc4 = to_vc4_dev(dev);
222 
223 	/* Disable sending interrupts for our driver's IRQs. */
224 	V3D_WRITE(V3D_INTDIS, V3D_DRIVER_IRQS);
225 
226 	/* Clear any pending interrupts we might have left. */
227 	V3D_WRITE(V3D_INTCTL, V3D_DRIVER_IRQS);
228 
229 	/* Finish any interrupt handler still in flight. */
230 	disable_irq(dev->irq);
231 
232 	cancel_work_sync(&vc4->overflow_mem_work);
233 }
234 
235 /** Reinitializes interrupt registers when a GPU reset is performed. */
236 void vc4_irq_reset(struct drm_device *dev)
237 {
238 	struct vc4_dev *vc4 = to_vc4_dev(dev);
239 	unsigned long irqflags;
240 
241 	/* Acknowledge any stale IRQs. */
242 	V3D_WRITE(V3D_INTCTL, V3D_DRIVER_IRQS);
243 
244 	/*
245 	 * Turn all our interrupts on.  Binner out of memory is the
246 	 * only one we expect to trigger at this point, since we've
247 	 * just come from poweron and haven't supplied any overflow
248 	 * memory yet.
249 	 */
250 	V3D_WRITE(V3D_INTENA, V3D_DRIVER_IRQS);
251 
252 	spin_lock_irqsave(&vc4->job_lock, irqflags);
253 	vc4_cancel_bin_job(dev);
254 	vc4_irq_finish_render_job(dev);
255 	spin_unlock_irqrestore(&vc4->job_lock, irqflags);
256 }
257