1 /*
2 * drivers/gpu/drm/omapdrm/omap_irq.c
3 *
4 * Copyright (C) 2012 Texas Instruments
5 * Author: Rob Clark <rob.clark@linaro.org>
6 *
7 * This program is free software; you can redistribute it and/or modify it
8 * under the terms of the GNU General Public License version 2 as published by
9 * the Free Software Foundation.
10 *
11 * This program is distributed in the hope that it will be useful, but WITHOUT
12 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
13 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
14 * more details.
15 *
16 * You should have received a copy of the GNU General Public License along with
17 * this program. If not, see <http://www.gnu.org/licenses/>.
18 */
19
20 #include "omap_drv.h"
21
22 static DEFINE_SPINLOCK(list_lock);
23
omap_irq_error_handler(struct omap_drm_irq * irq,uint32_t irqstatus)24 static void omap_irq_error_handler(struct omap_drm_irq *irq,
25 uint32_t irqstatus)
26 {
27 DRM_ERROR("errors: %08x\n", irqstatus);
28 }
29
30 /* call with list_lock and dispc runtime held */
omap_irq_update(struct drm_device * dev)31 static void omap_irq_update(struct drm_device *dev)
32 {
33 struct omap_drm_private *priv = dev->dev_private;
34 struct omap_drm_irq *irq;
35 uint32_t irqmask = priv->vblank_mask;
36
37 assert_spin_locked(&list_lock);
38
39 list_for_each_entry(irq, &priv->irq_list, node)
40 irqmask |= irq->irqmask;
41
42 DBG("irqmask=%08x", irqmask);
43
44 dispc_write_irqenable(irqmask);
45 dispc_read_irqenable(); /* flush posted write */
46 }
47
__omap_irq_register(struct drm_device * dev,struct omap_drm_irq * irq)48 void __omap_irq_register(struct drm_device *dev, struct omap_drm_irq *irq)
49 {
50 struct omap_drm_private *priv = dev->dev_private;
51 unsigned long flags;
52
53 spin_lock_irqsave(&list_lock, flags);
54
55 if (!WARN_ON(irq->registered)) {
56 irq->registered = true;
57 list_add(&irq->node, &priv->irq_list);
58 omap_irq_update(dev);
59 }
60
61 spin_unlock_irqrestore(&list_lock, flags);
62 }
63
omap_irq_register(struct drm_device * dev,struct omap_drm_irq * irq)64 void omap_irq_register(struct drm_device *dev, struct omap_drm_irq *irq)
65 {
66 dispc_runtime_get();
67
68 __omap_irq_register(dev, irq);
69
70 dispc_runtime_put();
71 }
72
__omap_irq_unregister(struct drm_device * dev,struct omap_drm_irq * irq)73 void __omap_irq_unregister(struct drm_device *dev, struct omap_drm_irq *irq)
74 {
75 unsigned long flags;
76
77 spin_lock_irqsave(&list_lock, flags);
78
79 if (!WARN_ON(!irq->registered)) {
80 irq->registered = false;
81 list_del(&irq->node);
82 omap_irq_update(dev);
83 }
84
85 spin_unlock_irqrestore(&list_lock, flags);
86 }
87
omap_irq_unregister(struct drm_device * dev,struct omap_drm_irq * irq)88 void omap_irq_unregister(struct drm_device *dev, struct omap_drm_irq *irq)
89 {
90 dispc_runtime_get();
91
92 __omap_irq_unregister(dev, irq);
93
94 dispc_runtime_put();
95 }
96
97 struct omap_irq_wait {
98 struct omap_drm_irq irq;
99 int count;
100 };
101
102 static DECLARE_WAIT_QUEUE_HEAD(wait_event);
103
wait_irq(struct omap_drm_irq * irq,uint32_t irqstatus)104 static void wait_irq(struct omap_drm_irq *irq, uint32_t irqstatus)
105 {
106 struct omap_irq_wait *wait =
107 container_of(irq, struct omap_irq_wait, irq);
108 wait->count--;
109 wake_up_all(&wait_event);
110 }
111
omap_irq_wait_init(struct drm_device * dev,uint32_t irqmask,int count)112 struct omap_irq_wait * omap_irq_wait_init(struct drm_device *dev,
113 uint32_t irqmask, int count)
114 {
115 struct omap_irq_wait *wait = kzalloc(sizeof(*wait), GFP_KERNEL);
116 wait->irq.irq = wait_irq;
117 wait->irq.irqmask = irqmask;
118 wait->count = count;
119 omap_irq_register(dev, &wait->irq);
120 return wait;
121 }
122
omap_irq_wait(struct drm_device * dev,struct omap_irq_wait * wait,unsigned long timeout)123 int omap_irq_wait(struct drm_device *dev, struct omap_irq_wait *wait,
124 unsigned long timeout)
125 {
126 int ret = wait_event_timeout(wait_event, (wait->count <= 0), timeout);
127 omap_irq_unregister(dev, &wait->irq);
128 kfree(wait);
129 if (ret == 0)
130 return -1;
131 return 0;
132 }
133
134 /**
135 * enable_vblank - enable vblank interrupt events
136 * @dev: DRM device
137 * @pipe: which irq to enable
138 *
139 * Enable vblank interrupts for @crtc. If the device doesn't have
140 * a hardware vblank counter, this routine should be a no-op, since
141 * interrupts will have to stay on to keep the count accurate.
142 *
143 * RETURNS
144 * Zero on success, appropriate errno if the given @crtc's vblank
145 * interrupt cannot be enabled.
146 */
omap_irq_enable_vblank(struct drm_device * dev,unsigned int pipe)147 int omap_irq_enable_vblank(struct drm_device *dev, unsigned int pipe)
148 {
149 struct omap_drm_private *priv = dev->dev_private;
150 struct drm_crtc *crtc = priv->crtcs[pipe];
151 unsigned long flags;
152
153 DBG("dev=%p, crtc=%u", dev, pipe);
154
155 spin_lock_irqsave(&list_lock, flags);
156 priv->vblank_mask |= pipe2vbl(crtc);
157 omap_irq_update(dev);
158 spin_unlock_irqrestore(&list_lock, flags);
159
160 return 0;
161 }
162
163 /**
164 * disable_vblank - disable vblank interrupt events
165 * @dev: DRM device
166 * @pipe: which irq to enable
167 *
168 * Disable vblank interrupts for @crtc. If the device doesn't have
169 * a hardware vblank counter, this routine should be a no-op, since
170 * interrupts will have to stay on to keep the count accurate.
171 */
omap_irq_disable_vblank(struct drm_device * dev,unsigned int pipe)172 void omap_irq_disable_vblank(struct drm_device *dev, unsigned int pipe)
173 {
174 struct omap_drm_private *priv = dev->dev_private;
175 struct drm_crtc *crtc = priv->crtcs[pipe];
176 unsigned long flags;
177
178 DBG("dev=%p, crtc=%u", dev, pipe);
179
180 spin_lock_irqsave(&list_lock, flags);
181 priv->vblank_mask &= ~pipe2vbl(crtc);
182 omap_irq_update(dev);
183 spin_unlock_irqrestore(&list_lock, flags);
184 }
185
omap_irq_handler(int irq,void * arg)186 static irqreturn_t omap_irq_handler(int irq, void *arg)
187 {
188 struct drm_device *dev = (struct drm_device *) arg;
189 struct omap_drm_private *priv = dev->dev_private;
190 struct omap_drm_irq *handler, *n;
191 unsigned long flags;
192 unsigned int id;
193 u32 irqstatus;
194
195 irqstatus = dispc_read_irqstatus();
196 dispc_clear_irqstatus(irqstatus);
197 dispc_read_irqstatus(); /* flush posted write */
198
199 VERB("irqs: %08x", irqstatus);
200
201 for (id = 0; id < priv->num_crtcs; id++) {
202 struct drm_crtc *crtc = priv->crtcs[id];
203
204 if (irqstatus & pipe2vbl(crtc))
205 drm_handle_vblank(dev, id);
206 }
207
208 spin_lock_irqsave(&list_lock, flags);
209 list_for_each_entry_safe(handler, n, &priv->irq_list, node) {
210 if (handler->irqmask & irqstatus) {
211 spin_unlock_irqrestore(&list_lock, flags);
212 handler->irq(handler, handler->irqmask & irqstatus);
213 spin_lock_irqsave(&list_lock, flags);
214 }
215 }
216 spin_unlock_irqrestore(&list_lock, flags);
217
218 return IRQ_HANDLED;
219 }
220
221 /*
222 * We need a special version, instead of just using drm_irq_install(),
223 * because we need to register the irq via omapdss. Once omapdss and
224 * omapdrm are merged together we can assign the dispc hwmod data to
225 * ourselves and drop these and just use drm_irq_{install,uninstall}()
226 */
227
omap_drm_irq_install(struct drm_device * dev)228 int omap_drm_irq_install(struct drm_device *dev)
229 {
230 struct omap_drm_private *priv = dev->dev_private;
231 struct omap_drm_irq *error_handler = &priv->error_handler;
232 int ret;
233
234 INIT_LIST_HEAD(&priv->irq_list);
235
236 dispc_runtime_get();
237 dispc_clear_irqstatus(0xffffffff);
238 dispc_runtime_put();
239
240 ret = dispc_request_irq(omap_irq_handler, dev);
241 if (ret < 0)
242 return ret;
243
244 error_handler->irq = omap_irq_error_handler;
245 error_handler->irqmask = DISPC_IRQ_OCP_ERR;
246
247 /* for now ignore DISPC_IRQ_SYNC_LOST_DIGIT.. really I think
248 * we just need to ignore it while enabling tv-out
249 */
250 error_handler->irqmask &= ~DISPC_IRQ_SYNC_LOST_DIGIT;
251
252 omap_irq_register(dev, error_handler);
253
254 dev->irq_enabled = true;
255
256 return 0;
257 }
258
omap_drm_irq_uninstall(struct drm_device * dev)259 void omap_drm_irq_uninstall(struct drm_device *dev)
260 {
261 unsigned long irqflags;
262 int i;
263
264 if (!dev->irq_enabled)
265 return;
266
267 dev->irq_enabled = false;
268
269 /* Wake up any waiters so they don't hang. */
270 if (dev->num_crtcs) {
271 spin_lock_irqsave(&dev->vbl_lock, irqflags);
272 for (i = 0; i < dev->num_crtcs; i++) {
273 wake_up(&dev->vblank[i].queue);
274 dev->vblank[i].enabled = false;
275 dev->vblank[i].last =
276 dev->driver->get_vblank_counter(dev, i);
277 }
278 spin_unlock_irqrestore(&dev->vbl_lock, irqflags);
279 }
280
281 dispc_free_irq(dev);
282 }
283