[PATCH 2/2] drm/i915: Fix GT wake FIFO free entries for VLV

ville.syrjala
2013-11-14T00:00:27Z

From: Ville Syrjälä <ville.syrjala@linux.intel.com>

On VLV the GTFIFOCTL register has other bits besides the number of free
entries in the GT wake FIFO. Apply a mask when we read th register to
make sure we don't misinterpret the number of free FIFO entries.

Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
---
drivers/gpu/drm/i915/i915_reg.h | 3 ++-
drivers/gpu/drm/i915/intel_uncore.c | 6 +++---
2 files changed, 5 insertions(+), 4 deletions(-)

diff --git a/drivers/gpu/drm/i915/i915_reg.h b/drivers/gpu/drm/i915/i915_reg.h
index e8f47de..e243105 100644
--- a/drivers/gpu/drm/i915/i915_reg.h
+++ b/drivers/gpu/drm/i915/i915_reg.h
@@ -4860,7 +4860,8 @@
#define GT_FIFO_IAWRERR (1<<1)
#define GT_FIFO_IARDERR (1<<0)

-#define GT_FIFO_FREE_ENTRIES 0x120008
+#define GTFIFOCTL 0x120008
+#define GT_FIFO_FREE_ENTRIES_MASK 0x7f
#define GT_FIFO_NUM_RESERVED_ENTRIES 20

#define HSW_IDICR 0x9008
diff --git a/drivers/gpu/drm/i915/intel_uncore.c b/drivers/gpu/drm/i915/intel_uncore.c
index a9849ab..71902c4 100644
--- a/drivers/gpu/drm/i915/intel_uncore.c
+++ b/drivers/gpu/drm/i915/intel_uncore.c
@@ -148,10 +148,10 @@ static int __gen6_gt_wait_for_fifo(struct drm_i915_private *dev_priv)

if (dev_priv->uncore.fifo_count < GT_FIFO_NUM_RESERVED_ENTRIES) {
int loop = 500;
- u32 fifo = __raw_i915_read32(dev_priv, GT_FIFO_FREE_ENTRIES);
+ u32 fifo = __raw_i915_read32(dev_priv, GTFIFOCTL) & GT_FIFO_FREE_ENTRIES_MASK;
while (fifo <= GT_FIFO_NUM_RESERVED_ENTRIES && loop--) {
udelay(10);
- fifo = __raw_i915_read32(dev_priv, GT_FIFO_FREE_ENTRIES);
+ fifo = __raw_i915_read32(dev_priv, GTFIFOCTL) & GT_FIFO_FREE_ENTRIES_MASK;
}
if (WARN_ON(loop < 0 && fifo <= GT_FIFO_NUM_RESERVED_ENTRIES))
++ret;
@@ -806,7 +806,7 @@ static int gen6_do_reset(struct drm_device *dev)
dev_priv->uncore.funcs.force_wake_put(dev_priv);

/* Restore fifo count */
- dev_priv->uncore.fifo_count = __raw_i915_read32(dev_priv, GT_FIFO_FREE_ENTRIES);
+ dev_priv->uncore.fifo_count = __raw_i915_read32(dev_priv, GTFIFOCTL) & GT_FIFO_FREE_ENTRIES_MASK;

spin_unlock_irqrestore(&dev_priv->uncore.lock, irqflags);
return ret;
--
1.8.1.5