drivers/gpu/drm/omapdrm/omap_irq.c

   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 struct omap_irq_wait {
  23         struct list_head node;
  24         wait_queue_head_t wq;
  25         uint32_t irqmask;
  26         int count;
  27 };
  28
  29 /* call with wait_lock and dispc runtime held */
  30 static void omap_irq_update(struct drm_device *dev)
  31 {
  32         struct omap_drm_private *priv = dev->dev_private;
  33         struct omap_irq_wait *wait;
  34         uint32_t irqmask = priv->irq_mask;
  35
  36         assert_spin_locked(&priv->wait_lock);
  37
  38         list_for_each_entry(wait, &priv->wait_list, node)
  39                 irqmask |= wait->irqmask;
  40
  41         DBG("irqmask=%08x", irqmask);
  42
  43         priv->dispc_ops->write_irqenable(irqmask);
  44 }
  45
  46 static void omap_irq_wait_handler(struct omap_irq_wait *wait)
  47 {
  48         wait->count--;
  49         wake_up(&wait->wq);
  50 }
  51
  52 struct omap_irq_wait * omap_irq_wait_init(struct drm_device *dev,
  53                 uint32_t irqmask, int count)
  54 {
  55         struct omap_drm_private *priv = dev->dev_private;
  56         struct omap_irq_wait *wait = kzalloc(sizeof(*wait), GFP_KERNEL);
  57         unsigned long flags;
  58
  59         init_waitqueue_head(&wait->wq);
  60         wait->irqmask = irqmask;
  61         wait->count = count;
  62
  63         spin_lock_irqsave(&priv->wait_lock, flags);
  64         list_add(&wait->node, &priv->wait_list);
  65         omap_irq_update(dev);
  66         spin_unlock_irqrestore(&priv->wait_lock, flags);
  67
  68         return wait;
  69 }
  70
  71 int omap_irq_wait(struct drm_device *dev, struct omap_irq_wait *wait,
  72                 unsigned long timeout)
  73 {
  74         struct omap_drm_private *priv = dev->dev_private;
  75         unsigned long flags;
  76         int ret;
  77
  78         ret = wait_event_timeout(wait->wq, (wait->count <= 0), timeout);
  79
  80         spin_lock_irqsave(&priv->wait_lock, flags);
  81         list_del(&wait->node);
  82         omap_irq_update(dev);
  83         spin_unlock_irqrestore(&priv->wait_lock, flags);
  84
  85         kfree(wait);
  86
  87         return ret == 0 ? -1 : 0;
  88 }
  89
  90 /**
  91  * enable_vblank - enable vblank interrupt events
  92  * @dev: DRM device
  93  * @pipe: which irq to enable
  94  *
  95  * Enable vblank interrupts for @crtc.  If the device doesn't have
  96  * a hardware vblank counter, this routine should be a no-op, since
  97  * interrupts will have to stay on to keep the count accurate.
  98  *
  99  * RETURNS
 100  * Zero on success, appropriate errno if the given @crtc's vblank
 101  * interrupt cannot be enabled.
 102  */
 103 int omap_irq_enable_vblank(struct drm_crtc *crtc)
 104 {
 105         struct drm_device *dev = crtc->dev;
 106         struct omap_drm_private *priv = dev->dev_private;
 107         unsigned long flags;
 108         enum omap_channel channel = omap_crtc_channel(crtc);
 109
 110         DBG("dev=%p, crtc=%u", dev, channel);
 111
 112         spin_lock_irqsave(&priv->wait_lock, flags);
 113         priv->irq_mask |= priv->dispc_ops->mgr_get_vsync_irq(channel);
 114         omap_irq_update(dev);
 115         spin_unlock_irqrestore(&priv->wait_lock, flags);
 116
 117         return 0;
 118 }
 119
 120 /**
 121  * disable_vblank - disable vblank interrupt events
 122  * @dev: DRM device
 123  * @pipe: which irq to enable
 124  *
 125  * Disable vblank interrupts for @crtc.  If the device doesn't have
 126  * a hardware vblank counter, this routine should be a no-op, since
 127  * interrupts will have to stay on to keep the count accurate.
 128  */
 129 void omap_irq_disable_vblank(struct drm_crtc *crtc)
 130 {
 131         struct drm_device *dev = crtc->dev;
 132         struct omap_drm_private *priv = dev->dev_private;
 133         unsigned long flags;
 134         enum omap_channel channel = omap_crtc_channel(crtc);
 135
 136         DBG("dev=%p, crtc=%u", dev, channel);
 137
 138         spin_lock_irqsave(&priv->wait_lock, flags);
 139         priv->irq_mask &= ~priv->dispc_ops->mgr_get_vsync_irq(channel);
 140         omap_irq_update(dev);
 141         spin_unlock_irqrestore(&priv->wait_lock, flags);
 142 }
 143
 144 static void omap_irq_fifo_underflow(struct omap_drm_private *priv,
 145                                     u32 irqstatus)
 146 {
 147         static DEFINE_RATELIMIT_STATE(_rs, DEFAULT_RATELIMIT_INTERVAL,
 148                                       DEFAULT_RATELIMIT_BURST);
 149         static const struct {
 150                 const char *name;
 151                 u32 mask;
 152         } sources[] = {
 153                 { "gfx", DISPC_IRQ_GFX_FIFO_UNDERFLOW },
 154                 { "vid1", DISPC_IRQ_VID1_FIFO_UNDERFLOW },
 155                 { "vid2", DISPC_IRQ_VID2_FIFO_UNDERFLOW },
 156                 { "vid3", DISPC_IRQ_VID3_FIFO_UNDERFLOW },
 157         };
 158
 159         const u32 mask = DISPC_IRQ_GFX_FIFO_UNDERFLOW
 160                        | DISPC_IRQ_VID1_FIFO_UNDERFLOW
 161                        | DISPC_IRQ_VID2_FIFO_UNDERFLOW
 162                        | DISPC_IRQ_VID3_FIFO_UNDERFLOW;
 163         unsigned int i;
 164
 165         spin_lock(&priv->wait_lock);
 166         irqstatus &= priv->irq_mask & mask;
 167         spin_unlock(&priv->wait_lock);
 168
 169         if (!irqstatus)
 170                 return;
 171
 172         if (!__ratelimit(&_rs))
 173                 return;
 174
 175         DRM_ERROR("FIFO underflow on ");
 176
 177         for (i = 0; i < ARRAY_SIZE(sources); ++i) {
 178                 if (sources[i].mask & irqstatus)
 179                         pr_cont("%s ", sources[i].name);
 180         }
 181
 182         pr_cont("(0x%08x)\n", irqstatus);
 183 }
 184
 185 static void omap_irq_ocp_error_handler(struct drm_device *dev,
 186         u32 irqstatus)
 187 {
 188         if (!(irqstatus & DISPC_IRQ_OCP_ERR))
 189                 return;
 190
 191         dev_err_ratelimited(dev->dev, "OCP error\n");
 192 }
 193
 194 static irqreturn_t omap_irq_handler(int irq, void *arg)
 195 {
 196         struct drm_device *dev = (struct drm_device *) arg;
 197         struct omap_drm_private *priv = dev->dev_private;
 198         struct omap_irq_wait *wait, *n;
 199         unsigned long flags;
 200         unsigned int id;
 201         u32 irqstatus;
 202
 203         irqstatus = priv->dispc_ops->read_irqstatus();
 204         priv->dispc_ops->clear_irqstatus(irqstatus);
 205         priv->dispc_ops->read_irqstatus();        /* flush posted write */
 206
 207         VERB("irqs: %08x", irqstatus);
 208
 209         for (id = 0; id < priv->num_crtcs; id++) {
 210                 struct drm_crtc *crtc = priv->crtcs[id];
 211                 enum omap_channel channel = omap_crtc_channel(crtc);
 212
 213                 if (irqstatus & priv->dispc_ops->mgr_get_vsync_irq(channel)) {
 214                         drm_handle_vblank(dev, id);
 215                         omap_crtc_vblank_irq(crtc);
 216                 }
 217
 218                 if (irqstatus & priv->dispc_ops->mgr_get_sync_lost_irq(channel))
 219                         omap_crtc_error_irq(crtc, irqstatus);
 220         }
 221
 222         omap_irq_ocp_error_handler(dev, irqstatus);
 223         omap_irq_fifo_underflow(priv, irqstatus);
 224
 225         spin_lock_irqsave(&priv->wait_lock, flags);
 226         list_for_each_entry_safe(wait, n, &priv->wait_list, node) {
 227                 if (wait->irqmask & irqstatus)
 228                         omap_irq_wait_handler(wait);
 229         }
 230         spin_unlock_irqrestore(&priv->wait_lock, flags);
 231
 232         return IRQ_HANDLED;
 233 }
 234
 235 static const u32 omap_underflow_irqs[] = {
 236         [OMAP_DSS_GFX] = DISPC_IRQ_GFX_FIFO_UNDERFLOW,
 237         [OMAP_DSS_VIDEO1] = DISPC_IRQ_VID1_FIFO_UNDERFLOW,
 238         [OMAP_DSS_VIDEO2] = DISPC_IRQ_VID2_FIFO_UNDERFLOW,
 239         [OMAP_DSS_VIDEO3] = DISPC_IRQ_VID3_FIFO_UNDERFLOW,
 240 };
 241
 242 /*
 243  * We need a special version, instead of just using drm_irq_install(),
 244  * because we need to register the irq via omapdss.  Once omapdss and
 245  * omapdrm are merged together we can assign the dispc hwmod data to
 246  * ourselves and drop these and just use drm_irq_{install,uninstall}()
 247  */
 248
 249 int omap_drm_irq_install(struct drm_device *dev)
 250 {
 251         struct omap_drm_private *priv = dev->dev_private;
 252         unsigned int num_mgrs = priv->dispc_ops->get_num_mgrs();
 253         unsigned int max_planes;
 254         unsigned int i;
 255         int ret;
 256
 257         spin_lock_init(&priv->wait_lock);
 258         INIT_LIST_HEAD(&priv->wait_list);
 259
 260         priv->irq_mask = DISPC_IRQ_OCP_ERR;
 261
 262         max_planes = min(ARRAY_SIZE(priv->planes),
 263                          ARRAY_SIZE(omap_underflow_irqs));
 264         for (i = 0; i < max_planes; ++i) {
 265                 if (priv->planes[i])
 266                         priv->irq_mask |= omap_underflow_irqs[i];
 267         }
 268
 269         for (i = 0; i < num_mgrs; ++i)
 270                 priv->irq_mask |= priv->dispc_ops->mgr_get_sync_lost_irq(i);
 271
 272         priv->dispc_ops->runtime_get();
 273         priv->dispc_ops->clear_irqstatus(0xffffffff);
 274         priv->dispc_ops->runtime_put();
 275
 276         ret = priv->dispc_ops->request_irq(omap_irq_handler, dev);
 277         if (ret < 0)
 278                 return ret;
 279
 280         dev->irq_enabled = true;
 281
 282         return 0;
 283 }
 284
 285 void omap_drm_irq_uninstall(struct drm_device *dev)
 286 {
 287         struct omap_drm_private *priv = dev->dev_private;
 288
 289         if (!dev->irq_enabled)
 290                 return;
 291
 292         dev->irq_enabled = false;
 293
 294         priv->dispc_ops->free_irq(dev);
 295 }