drivers/gpu/drm/omapdrm/omap_irq.c

   1 /*
   2  * Copyright (C) 2011 Texas Instruments Incorporated - http://www.ti.com/
   3  * Author: Rob Clark <rob.clark@linaro.org>
   4  *
   5  * This program is free software; you can redistribute it and/or modify it
   6  * under the terms of the GNU General Public License version 2 as published by
   7  * the Free Software Foundation.
   8  *
   9  * This program is distributed in the hope that it will be useful, but WITHOUT
  10  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  11  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
  12  * more details.
  13  *
  14  * You should have received a copy of the GNU General Public License along with
  15  * this program.  If not, see <http://www.gnu.org/licenses/>.
  16  */
  17
  18 #include "omap_drv.h"
  19
  20 struct omap_irq_wait {
  21         struct list_head node;
  22         wait_queue_head_t wq;
  23         uint32_t irqmask;
  24         int count;
  25 };
  26
  27 /* call with wait_lock and dispc runtime held */
  28 static void omap_irq_update(struct drm_device *dev)
  29 {
  30         struct omap_drm_private *priv = dev->dev_private;
  31         struct omap_irq_wait *wait;
  32         uint32_t irqmask = priv->irq_mask;
  33
  34         assert_spin_locked(&priv->wait_lock);
  35
  36         list_for_each_entry(wait, &priv->wait_list, node)
  37                 irqmask |= wait->irqmask;
  38
  39         DBG("irqmask=%08x", irqmask);
  40
  41         priv->dispc_ops->write_irqenable(irqmask);
  42 }
  43
  44 static void omap_irq_wait_handler(struct omap_irq_wait *wait)
  45 {
  46         wait->count--;
  47         wake_up(&wait->wq);
  48 }
  49
  50 struct omap_irq_wait * omap_irq_wait_init(struct drm_device *dev,
  51                 uint32_t irqmask, int count)
  52 {
  53         struct omap_drm_private *priv = dev->dev_private;
  54         struct omap_irq_wait *wait = kzalloc(sizeof(*wait), GFP_KERNEL);
  55         unsigned long flags;
  56
  57         init_waitqueue_head(&wait->wq);
  58         wait->irqmask = irqmask;
  59         wait->count = count;
  60
  61         spin_lock_irqsave(&priv->wait_lock, flags);
  62         list_add(&wait->node, &priv->wait_list);
  63         omap_irq_update(dev);
  64         spin_unlock_irqrestore(&priv->wait_lock, flags);
  65
  66         return wait;
  67 }
  68
  69 int omap_irq_wait(struct drm_device *dev, struct omap_irq_wait *wait,
  70                 unsigned long timeout)
  71 {
  72         struct omap_drm_private *priv = dev->dev_private;
  73         unsigned long flags;
  74         int ret;
  75
  76         ret = wait_event_timeout(wait->wq, (wait->count <= 0), timeout);
  77
  78         spin_lock_irqsave(&priv->wait_lock, flags);
  79         list_del(&wait->node);
  80         omap_irq_update(dev);
  81         spin_unlock_irqrestore(&priv->wait_lock, flags);
  82
  83         kfree(wait);
  84
  85         return ret == 0 ? -1 : 0;
  86 }
  87
  88 /**
  89  * enable_vblank - enable vblank interrupt events
  90  * @dev: DRM device
  91  * @pipe: which irq to enable
  92  *
  93  * Enable vblank interrupts for @crtc.  If the device doesn't have
  94  * a hardware vblank counter, this routine should be a no-op, since
  95  * interrupts will have to stay on to keep the count accurate.
  96  *
  97  * RETURNS
  98  * Zero on success, appropriate errno if the given @crtc's vblank
  99  * interrupt cannot be enabled.
 100  */
 101 int omap_irq_enable_vblank(struct drm_crtc *crtc)
 102 {
 103         struct drm_device *dev = crtc->dev;
 104         struct omap_drm_private *priv = dev->dev_private;
 105         unsigned long flags;
 106         enum omap_channel channel = omap_crtc_channel(crtc);
 107
 108         DBG("dev=%p, crtc=%u", dev, channel);
 109
 110         spin_lock_irqsave(&priv->wait_lock, flags);
 111         priv->irq_mask |= priv->dispc_ops->mgr_get_vsync_irq(channel);
 112         omap_irq_update(dev);
 113         spin_unlock_irqrestore(&priv->wait_lock, flags);
 114
 115         return 0;
 116 }
 117
 118 /**
 119  * disable_vblank - disable vblank interrupt events
 120  * @dev: DRM device
 121  * @pipe: which irq to enable
 122  *
 123  * Disable vblank interrupts for @crtc.  If the device doesn't have
 124  * a hardware vblank counter, this routine should be a no-op, since
 125  * interrupts will have to stay on to keep the count accurate.
 126  */
 127 void omap_irq_disable_vblank(struct drm_crtc *crtc)
 128 {
 129         struct drm_device *dev = crtc->dev;
 130         struct omap_drm_private *priv = dev->dev_private;
 131         unsigned long flags;
 132         enum omap_channel channel = omap_crtc_channel(crtc);
 133
 134         DBG("dev=%p, crtc=%u", dev, channel);
 135
 136         spin_lock_irqsave(&priv->wait_lock, flags);
 137         priv->irq_mask &= ~priv->dispc_ops->mgr_get_vsync_irq(channel);
 138         omap_irq_update(dev);
 139         spin_unlock_irqrestore(&priv->wait_lock, flags);
 140 }
 141
 142 static void omap_irq_fifo_underflow(struct omap_drm_private *priv,
 143                                     u32 irqstatus)
 144 {
 145         static DEFINE_RATELIMIT_STATE(_rs, DEFAULT_RATELIMIT_INTERVAL,
 146                                       DEFAULT_RATELIMIT_BURST);
 147         static const struct {
 148                 const char *name;
 149                 u32 mask;
 150         } sources[] = {
 151                 { "gfx", DISPC_IRQ_GFX_FIFO_UNDERFLOW },
 152                 { "vid1", DISPC_IRQ_VID1_FIFO_UNDERFLOW },
 153                 { "vid2", DISPC_IRQ_VID2_FIFO_UNDERFLOW },
 154                 { "vid3", DISPC_IRQ_VID3_FIFO_UNDERFLOW },
 155         };
 156
 157         const u32 mask = DISPC_IRQ_GFX_FIFO_UNDERFLOW
 158                        | DISPC_IRQ_VID1_FIFO_UNDERFLOW
 159                        | DISPC_IRQ_VID2_FIFO_UNDERFLOW
 160                        | DISPC_IRQ_VID3_FIFO_UNDERFLOW;
 161         unsigned int i;
 162
 163         spin_lock(&priv->wait_lock);
 164         irqstatus &= priv->irq_mask & mask;
 165         spin_unlock(&priv->wait_lock);
 166
 167         if (!irqstatus)
 168                 return;
 169
 170         if (!__ratelimit(&_rs))
 171                 return;
 172
 173         DRM_ERROR("FIFO underflow on ");
 174
 175         for (i = 0; i < ARRAY_SIZE(sources); ++i) {
 176                 if (sources[i].mask & irqstatus)
 177                         pr_cont("%s ", sources[i].name);
 178         }
 179
 180         pr_cont("(0x%08x)\n", irqstatus);
 181 }
 182
 183 static void omap_irq_ocp_error_handler(struct drm_device *dev,
 184         u32 irqstatus)
 185 {
 186         if (!(irqstatus & DISPC_IRQ_OCP_ERR))
 187                 return;
 188
 189         dev_err_ratelimited(dev->dev, "OCP error\n");
 190 }
 191
 192 static irqreturn_t omap_irq_handler(int irq, void *arg)
 193 {
 194         struct drm_device *dev = (struct drm_device *) arg;
 195         struct omap_drm_private *priv = dev->dev_private;
 196         struct omap_irq_wait *wait, *n;
 197         unsigned long flags;
 198         unsigned int id;
 199         u32 irqstatus;
 200
 201         irqstatus = priv->dispc_ops->read_irqstatus();
 202         priv->dispc_ops->clear_irqstatus(irqstatus);
 203         priv->dispc_ops->read_irqstatus();        /* flush posted write */
 204
 205         VERB("irqs: %08x", irqstatus);
 206
 207         for (id = 0; id < priv->num_crtcs; id++) {
 208                 struct drm_crtc *crtc = priv->crtcs[id];
 209                 enum omap_channel channel = omap_crtc_channel(crtc);
 210
 211                 if (irqstatus & priv->dispc_ops->mgr_get_vsync_irq(channel)) {
 212                         drm_handle_vblank(dev, id);
 213                         omap_crtc_vblank_irq(crtc);
 214                 }
 215
 216                 if (irqstatus & priv->dispc_ops->mgr_get_sync_lost_irq(channel))
 217                         omap_crtc_error_irq(crtc, irqstatus);
 218         }
 219
 220         omap_irq_ocp_error_handler(dev, irqstatus);
 221         omap_irq_fifo_underflow(priv, irqstatus);
 222
 223         spin_lock_irqsave(&priv->wait_lock, flags);
 224         list_for_each_entry_safe(wait, n, &priv->wait_list, node) {
 225                 if (wait->irqmask & irqstatus)
 226                         omap_irq_wait_handler(wait);
 227         }
 228         spin_unlock_irqrestore(&priv->wait_lock, flags);
 229
 230         return IRQ_HANDLED;
 231 }
 232
 233 static const u32 omap_underflow_irqs[] = {
 234         [OMAP_DSS_GFX] = DISPC_IRQ_GFX_FIFO_UNDERFLOW,
 235         [OMAP_DSS_VIDEO1] = DISPC_IRQ_VID1_FIFO_UNDERFLOW,
 236         [OMAP_DSS_VIDEO2] = DISPC_IRQ_VID2_FIFO_UNDERFLOW,
 237         [OMAP_DSS_VIDEO3] = DISPC_IRQ_VID3_FIFO_UNDERFLOW,
 238 };
 239
 240 /*
 241  * We need a special version, instead of just using drm_irq_install(),
 242  * because we need to register the irq via omapdss.  Once omapdss and
 243  * omapdrm are merged together we can assign the dispc hwmod data to
 244  * ourselves and drop these and just use drm_irq_{install,uninstall}()
 245  */
 246
 247 int omap_drm_irq_install(struct drm_device *dev)
 248 {
 249         struct omap_drm_private *priv = dev->dev_private;
 250         unsigned int num_mgrs = priv->dispc_ops->get_num_mgrs();
 251         unsigned int max_planes;
 252         unsigned int i;
 253         int ret;
 254
 255         spin_lock_init(&priv->wait_lock);
 256         INIT_LIST_HEAD(&priv->wait_list);
 257
 258         priv->irq_mask = DISPC_IRQ_OCP_ERR;
 259
 260         max_planes = min(ARRAY_SIZE(priv->planes),
 261                          ARRAY_SIZE(omap_underflow_irqs));
 262         for (i = 0; i < max_planes; ++i) {
 263                 if (priv->planes[i])
 264                         priv->irq_mask |= omap_underflow_irqs[i];
 265         }
 266
 267         for (i = 0; i < num_mgrs; ++i)
 268                 priv->irq_mask |= priv->dispc_ops->mgr_get_sync_lost_irq(i);
 269
 270         priv->dispc_ops->runtime_get();
 271         priv->dispc_ops->clear_irqstatus(0xffffffff);
 272         priv->dispc_ops->runtime_put();
 273
 274         ret = priv->dispc_ops->request_irq(omap_irq_handler, dev);
 275         if (ret < 0)
 276                 return ret;
 277
 278         dev->irq_enabled = true;
 279
 280         return 0;
 281 }
 282
 283 void omap_drm_irq_uninstall(struct drm_device *dev)
 284 {
 285         struct omap_drm_private *priv = dev->dev_private;
 286
 287         if (!dev->irq_enabled)
 288                 return;
 289
 290         dev->irq_enabled = false;
 291
 292         priv->dispc_ops->free_irq(dev);
 293 }