drm: i915: Add ioctl for scheduling buffer swaps at vertical blanks.
This uses the core facility to schedule a driver callback that will be called
ASAP after the given vertical blank interrupt with the HW lock held.
Signed-off-by: Dave Airlie <airlied@linux.ie>
diff --git a/drivers/char/drm/i915_irq.c b/drivers/char/drm/i915_irq.c
index 33d401876..a93f1f3 100644
--- a/drivers/char/drm/i915_irq.c
+++ b/drivers/char/drm/i915_irq.c
@@ -37,6 +37,99 @@
#define MAX_NOPID ((u32)~0)
+/**
+ * Emit blits for scheduled buffer swaps.
+ *
+ * This function will be called with the HW lock held.
+ */
+static void i915_vblank_tasklet(drm_device_t *dev)
+{
+ drm_i915_private_t *dev_priv = (drm_i915_private_t *) dev->dev_private;
+ unsigned int irqflags;
+ struct list_head *list, *tmp;
+
+ DRM_DEBUG("\n");
+
+ spin_lock_irqsave(&dev_priv->swaps_lock, irqflags);
+
+ list_for_each_safe(list, tmp, &dev_priv->vbl_swaps.head) {
+ drm_i915_vbl_swap_t *vbl_swap =
+ list_entry(list, drm_i915_vbl_swap_t, head);
+ atomic_t *counter = vbl_swap->pipe ? &dev->vbl_received2 :
+ &dev->vbl_received;
+
+ if ((atomic_read(counter) - vbl_swap->sequence) <= (1<<23)) {
+ drm_drawable_info_t *drw;
+
+ spin_unlock(&dev_priv->swaps_lock);
+
+ spin_lock(&dev->drw_lock);
+
+ drw = drm_get_drawable_info(dev, vbl_swap->drw_id);
+
+ if (drw) {
+ int i, num_rects = drw->num_rects;
+ drm_clip_rect_t *rect = drw->rects;
+ drm_i915_sarea_t *sarea_priv =
+ dev_priv->sarea_priv;
+ u32 cpp = dev_priv->cpp;
+ u32 cmd = (cpp == 4) ? (XY_SRC_COPY_BLT_CMD |
+ XY_SRC_COPY_BLT_WRITE_ALPHA |
+ XY_SRC_COPY_BLT_WRITE_RGB)
+ : XY_SRC_COPY_BLT_CMD;
+ u32 pitchropcpp = (sarea_priv->pitch * cpp) |
+ (0xcc << 16) | (cpp << 23) |
+ (1 << 24);
+ RING_LOCALS;
+
+ i915_kernel_lost_context(dev);
+
+ BEGIN_LP_RING(6);
+
+ OUT_RING(GFX_OP_DRAWRECT_INFO);
+ OUT_RING(0);
+ OUT_RING(0);
+ OUT_RING(sarea_priv->width |
+ sarea_priv->height << 16);
+ OUT_RING(sarea_priv->width |
+ sarea_priv->height << 16);
+ OUT_RING(0);
+
+ ADVANCE_LP_RING();
+
+ sarea_priv->ctxOwner = DRM_KERNEL_CONTEXT;
+
+ for (i = 0; i < num_rects; i++, rect++) {
+ BEGIN_LP_RING(8);
+
+ OUT_RING(cmd);
+ OUT_RING(pitchropcpp);
+ OUT_RING((rect->y1 << 16) | rect->x1);
+ OUT_RING((rect->y2 << 16) | rect->x2);
+ OUT_RING(sarea_priv->front_offset);
+ OUT_RING((rect->y1 << 16) | rect->x1);
+ OUT_RING(pitchropcpp & 0xffff);
+ OUT_RING(sarea_priv->back_offset);
+
+ ADVANCE_LP_RING();
+ }
+ }
+
+ spin_unlock(&dev->drw_lock);
+
+ spin_lock(&dev_priv->swaps_lock);
+
+ list_del(list);
+
+ drm_free(vbl_swap, sizeof(*vbl_swap), DRM_MEM_DRIVER);
+
+ dev_priv->swaps_pending--;
+ }
+ }
+
+ spin_unlock_irqrestore(&dev_priv->swaps_lock, irqflags);
+}
+
irqreturn_t i915_driver_irq_handler(DRM_IRQ_ARGS)
{
drm_device_t *dev = (drm_device_t *) arg;
@@ -72,6 +165,8 @@
DRM_WAKEUP(&dev->vbl_queue);
drm_vbl_send_signals(dev);
+
+ drm_locked_tasklet(dev, i915_vblank_tasklet);
}
return IRQ_HANDLED;
@@ -271,6 +366,90 @@
return 0;
}
+/**
+ * Schedule buffer swap at given vertical blank.
+ */
+int i915_vblank_swap(DRM_IOCTL_ARGS)
+{
+ DRM_DEVICE;
+ drm_i915_private_t *dev_priv = dev->dev_private;
+ drm_i915_vblank_swap_t swap;
+ drm_i915_vbl_swap_t *vbl_swap;
+ unsigned int irqflags;
+ struct list_head *list;
+
+ if (!dev_priv) {
+ DRM_ERROR("%s called with no initialization\n", __func__);
+ return DRM_ERR(EINVAL);
+ }
+
+ if (dev_priv->sarea_priv->rotation) {
+ DRM_DEBUG("Rotation not supported\n");
+ return DRM_ERR(EINVAL);
+ }
+
+ if (dev_priv->swaps_pending >= 100) {
+ DRM_DEBUG("Too many swaps queued\n");
+ return DRM_ERR(EBUSY);
+ }
+
+ DRM_COPY_FROM_USER_IOCTL(swap, (drm_i915_vblank_swap_t __user *) data,
+ sizeof(swap));
+
+ if (swap.pipe > 1 || !(dev_priv->vblank_pipe & (1 << swap.pipe))) {
+ DRM_ERROR("Invalid pipe %d\n", swap.pipe);
+ return DRM_ERR(EINVAL);
+ }
+
+ spin_lock_irqsave(&dev->drw_lock, irqflags);
+
+ if (!drm_get_drawable_info(dev, swap.drawable)) {
+ spin_unlock_irqrestore(&dev->drw_lock, irqflags);
+ DRM_ERROR("Invalid drawable ID %d\n", swap.drawable);
+ return DRM_ERR(EINVAL);
+ }
+
+ spin_unlock_irqrestore(&dev->drw_lock, irqflags);
+
+ spin_lock_irqsave(&dev_priv->swaps_lock, irqflags);
+
+ list_for_each(list, &dev_priv->vbl_swaps.head) {
+ vbl_swap = list_entry(list, drm_i915_vbl_swap_t, head);
+
+ if (vbl_swap->drw_id == swap.drawable &&
+ vbl_swap->pipe == swap.pipe &&
+ vbl_swap->sequence == swap.sequence) {
+ spin_unlock_irqrestore(&dev_priv->swaps_lock, irqflags);
+ DRM_DEBUG("Already scheduled\n");
+ return 0;
+ }
+ }
+
+ spin_unlock_irqrestore(&dev_priv->swaps_lock, irqflags);
+
+ vbl_swap = drm_calloc(1, sizeof(vbl_swap), DRM_MEM_DRIVER);
+
+ if (!vbl_swap) {
+ DRM_ERROR("Failed to allocate memory to queue swap\n");
+ return DRM_ERR(ENOMEM);
+ }
+
+ DRM_DEBUG("\n");
+
+ vbl_swap->drw_id = swap.drawable;
+ vbl_swap->pipe = swap.pipe;
+ vbl_swap->sequence = swap.sequence;
+
+ spin_lock_irqsave(&dev_priv->swaps_lock, irqflags);
+
+ list_add_tail((struct list_head *)vbl_swap, &dev_priv->vbl_swaps.head);
+ dev_priv->swaps_pending++;
+
+ spin_unlock_irqrestore(&dev_priv->swaps_lock, irqflags);
+
+ return 0;
+}
+
/* drm_dma.h hooks
*/
void i915_driver_irq_preinstall(drm_device_t * dev)
@@ -286,6 +465,10 @@
{
drm_i915_private_t *dev_priv = (drm_i915_private_t *) dev->dev_private;
+ dev_priv->swaps_lock = SPIN_LOCK_UNLOCKED;
+ INIT_LIST_HEAD(&dev_priv->vbl_swaps.head);
+ dev_priv->swaps_pending = 0;
+
i915_enable_interrupt(dev);
DRM_INIT_WAITQUEUE(&dev_priv->irq_queue);
}