Remove plane->pipe mapping from SAREA private after all

We can figure out which pipe a given plane is mapped to by looking at the
display control registers instead of tracking it in a new SAREA private field.
If this becomes a performance problem, we could move to an ioctl based solution
by adding a new parameter for the DDX to set (defaulting to the old behavior if
the param was never set of course).

3 files changed, 27 insertions, 7 deletions

diff --git a/shared-core/i915_drm.h b/shared-core/i915_drm.h
index 575b182a..a57ffa73 100644
--- a/shared-core/i915_drm.h
+++ b/shared-core/i915_drm.h
@@ -114,9 +114,6 @@ typedef struct _drm_i915_sarea {
 	int planeB_w;
 	int planeB_h;
 
-	int planeA_pipe;
-	int planeB_pipe;
-
 	/* Triple buffering */
 	drm_handle_t third_handle;
 	int third_offset;
diff --git a/shared-core/i915_drv.h b/shared-core/i915_drv.h
index c5f51897..899817ec 100644
--- a/shared-core/i915_drv.h
+++ b/shared-core/i915_drv.h
@@ -490,6 +490,11 @@ extern int i915_wait_ring(struct drm_device * dev, int n, const char *caller);
 #define DISPLAY_PLANE_A           (0<<20)
 #define DISPLAY_PLANE_B           (1<<20)
 
+/* Display regs */
+#define DSPACNTR                0x70180
+#define DSPBCNTR                0x71180
+#define DISPPLANE_SEL_PIPE_MASK                 (1<<24)
+
 /* Define the region of interest for the binner:
  */
 #define CMD_OP_BIN_CONTROL	 ((0x3<<29)|(0x1d<<24)|(0x84<<16)|4)
diff --git a/shared-core/i915_irq.c b/shared-core/i915_irq.c
index 72c61876..804e3fb1 100644
--- a/shared-core/i915_irq.c
+++ b/shared-core/i915_irq.c
@@ -38,6 +38,26 @@
 #define MAX_NOPID ((u32)~0)
 
 /**
+ * i915_get_pipe - return the the pipe associated with a given plane
+ * @dev: DRM device
+ * @plane: plane to look for
+ *
+ * We need to get the pipe associated with a given plane to correctly perform
+ * vblank driven swapping, and they may not always be equal.  So look up the
+ * pipe associated with @plane here.
+ */
+static int
+i915_get_pipe(struct drm_device *dev, int plane)
+{
+	drm_i915_private_t *dev_priv = (drm_i915_private_t *) dev->dev_private;
+	u32 dspcntr;
+
+	dspcntr = plane ? I915_READ(DSPBCNTR) : I915_READ(DSPACNTR);
+
+	return dspcntr & DISPPLANE_SEL_PIPE_MASK ? 1 : 0;
+}
+
+/**
  * Emit a synchronous flip.
  *
  * This function must be called with the drawable spinlock held.
@@ -124,8 +144,7 @@ static void i915_vblank_tasklet(struct drm_device *dev)
 	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);
-		int pipe = vbl_swap->plane ? sarea_priv->planeB_pipe :
-			sarea_priv->planeA_pipe;
+		int pipe = i915_get_pipe(dev, vbl_swap->plane);
 
 		if ((counter[pipe] - vbl_swap->sequence) > (1<<23))
 			continue;
@@ -565,7 +584,6 @@ int i915_vblank_swap(struct drm_device *dev, void *data,
 	unsigned int pipe, seqtype, curseq, plane;
 	unsigned long irqflags;
 	struct list_head *list;
-	drm_i915_sarea_t *sarea_priv = dev_priv->sarea_priv;
 
 	if (!dev_priv) {
 		DRM_ERROR("%s called with no initialization\n", __func__);
@@ -585,7 +603,7 @@ int i915_vblank_swap(struct drm_device *dev, void *data,
 	}
 
 	plane = (swap->seqtype & _DRM_VBLANK_SECONDARY) ? 1 : 0;
-	pipe = plane ? sarea_priv->planeB_pipe : sarea_priv->planeA_pipe;
+	pipe = i915_get_pipe(dev, plane);
 
 	seqtype = swap->seqtype & (_DRM_VBLANK_RELATIVE | _DRM_VBLANK_ABSOLUTE);