[PATCH 6/7] drm/i915: vlv: fix mapping of pipestat enable to status bits

[Imre Deak <imre.deak@intel.com>]

At least on VLV we can't get at the pipestat status bits by simply right
shifting the corresponding enable bits. The mapping between enable and
status bits for the sprite0,1 flip done and the PSR events don't follow
this rule, so we need to map them separately.

The PSR enable for pipe A is DPFLIPSTAT[22], but I haven't added support
for this, since there is no user of it atm. Until support is added WARN
if someone tries to enable PSR interrupts, or tries to enable the same
(1 << 6) bit on pipe B, which MBZ.

Signed-off-by: Imre Deak <imre.deak@intel.com>
---
 drivers/gpu/drm/i915/i915_irq.c | 36 +++++++++++++++++++++++++++++++++++-
 drivers/gpu/drm/i915/i915_reg.h |  3 +++
 2 files changed, 38 insertions(+), 1 deletion(-)

diff --git a/drivers/gpu/drm/i915/i915_irq.c b/drivers/gpu/drm/i915/i915_irq.c
index ec56a70..eea5398 100644
--- a/drivers/gpu/drm/i915/i915_irq.c
+++ b/drivers/gpu/drm/i915/i915_irq.c
@@ -471,9 +471,29 @@ done:
 	return ret;
 }
 
+static void set_pipestat_enable_bit(u32 status_mask, u32 status_bit,
+				    u32 enable_bit, u32 *enable_mask)
+{
+	if (status_mask & status_bit)
+		*enable_mask |= enable_bit;
+	else
+		*enable_mask &= ~enable_bit;
+}
+
 static u32 pipestat_to_enable_mask(struct drm_device *dev, u32 status_mask)
 {
-	return status_mask << 16;
+	u32 enable_mask = status_mask << 16;
+
+	if (!IS_VALLEYVIEW(dev))
+		return enable_mask;
+
+	enable_mask &= ~PIPE_FIFO_UNDERRUN_STATUS;
+	set_pipestat_enable_bit(status_mask, SPRITE1_FLIP_DONE_INT_STATUS_VLV,
+				SPRITE1_FLIP_DONE_INT_EN_VLV, &enable_mask);
+	set_pipestat_enable_bit(enable_mask, SPRITE0_FLIP_DONE_INT_STATUS_VLV,
+				SPRITE0_FLIP_DONE_INT_EN_VLV, &enable_mask);
+
+	return enable_mask;
 }
 
 void
@@ -489,6 +509,13 @@ i915_enable_pipestat(drm_i915_private_t *dev_priv, enum pipe pipe,
 	if (WARN_ON_ONCE(status_mask & ~PIPESTAT_INT_STATUS_MASK))
 		return;
 
+	/*
+	 * On pipe A we don't support the PSR interrupt yet, on pipe B the
+	 * same bit MBZ.
+	 */
+	if (WARN_ON_ONCE(status_mask & PIPE_A_PSR_STATUS_VLV))
+		return;
+
 	enable_mask = pipestat_to_enable_mask(dev_priv->dev, status_mask);
 	if ((pipestat & enable_mask) == enable_mask)
 		return;
@@ -512,6 +539,13 @@ i915_disable_pipestat(drm_i915_private_t *dev_priv, enum pipe pipe,
 	if (WARN_ON_ONCE(status_mask & ~PIPESTAT_INT_STATUS_MASK))
 		return;
 
+	/*
+	 * On pipe A we don't support the PSR interrupt yet, on pipe B the
+	 * same bit MBZ.
+	 */
+	if (WARN_ON_ONCE(status_mask & PIPE_A_PSR_STATUS_VLV))
+		return;
+
 	enable_mask = pipestat_to_enable_mask(dev_priv->dev, status_mask);
 	if ((pipestat & enable_mask) == 0)
 		return;
diff --git a/drivers/gpu/drm/i915/i915_reg.h b/drivers/gpu/drm/i915/i915_reg.h
index 599c7f6..c998c4f 100644
--- a/drivers/gpu/drm/i915/i915_reg.h
+++ b/drivers/gpu/drm/i915/i915_reg.h
@@ -3240,6 +3240,7 @@
 #define   PIPE_LEGACY_BLC_EVENT_ENABLE		(1UL<<22)
 #define   PIPE_ODD_FIELD_INTERRUPT_ENABLE	(1UL<<21)
 #define   PIPE_EVEN_FIELD_INTERRUPT_ENABLE	(1UL<<20)
+#define   PIPE_B_PSR_INTERRUPT_ENABLE_VLV	(1UL<<19)
 #define   PIPE_HOTPLUG_TV_INTERRUPT_ENABLE	(1UL<<18) /* pre-965 */
 #define   PIPE_START_VBLANK_INTERRUPT_ENABLE	(1UL<<18) /* 965 or later */
 #define   PIPE_VBLANK_INTERRUPT_ENABLE		(1UL<<17)
@@ -3256,8 +3257,10 @@
 #define   PIPE_DISPLAY_LINE_COMPARE_STATUS	(1UL<<8)
 #define   PIPE_DPST_EVENT_STATUS		(1UL<<7)
 #define   PIPE_LEGACY_BLC_EVENT_STATUS		(1UL<<6)
+#define   PIPE_A_PSR_STATUS_VLV			(1UL<<6)
 #define   PIPE_ODD_FIELD_INTERRUPT_STATUS	(1UL<<5)
 #define   PIPE_EVEN_FIELD_INTERRUPT_STATUS	(1UL<<4)
+#define   PIPE_B_PSR_STATUS_VLV			(1UL<<3)
 #define   PIPE_HOTPLUG_TV_INTERRUPT_STATUS	(1UL<<2) /* pre-965 */
 #define   PIPE_START_VBLANK_INTERRUPT_STATUS	(1UL<<2) /* 965 or later */
 #define   PIPE_VBLANK_INTERRUPT_STATUS		(1UL<<1)
-- 
1.8.4