For some reason snb has 2 fields to set ppgtt cacheability. This one
here does not exist on gen7.
This might explain why ppgtt wasn't a win on snb like on ivb - not
enough pte caching.
Signed-Off-by: Daniel Vetter <daniel.vetter at ffwll.ch>
---
drivers/gpu/drm/i915/i915_gem.c | 3 +++
drivers/gpu/drm/i915/i915_reg.h | 4 ++++
2 files changed, 7 insertions(+), 0 deletions(-)
diff --git a/drivers/gpu/drm/i915/i915_gem.c b/drivers/gpu/drm/i915/i915_gem.c
index 5dc5f42..cab70ef 100644
--- a/drivers/gpu/drm/i915/i915_gem.c
+++ b/drivers/gpu/drm/i915/i915_gem.c
@@ -3766,6 +3766,9 @@ void i915_gem_init_ppgtt(struct drm_device *dev)
if (INTEL_INFO(dev)->gen == 6) {
uint32_t ecochk, gab_ctl, ecobits;
+ ecobits = I915_READ(GAC_ECO_BITS);
+ I915_WRITE(GAC_ECO_BITS, ecobits | ECOBITS_PPGTT_CACHE64B);
+
gab_ctl = I915_READ(GAB_CTL);
I915_WRITE(GAB_CTL, gab_ctl | GAB_CTL_CONT_AFTER_PAGEFAULT);
diff --git a/drivers/gpu/drm/i915/i915_reg.h b/drivers/gpu/drm/i915/i915_reg.h
index e72c251..5457980 100644
--- a/drivers/gpu/drm/i915/i915_reg.h
+++ b/drivers/gpu/drm/i915/i915_reg.h
@@ -125,6 +125,10 @@
#define ECOCHK_PPGTT_CACHE64B (0x3<<3)
#define ECOCHK_PPGTT_CACHE4B (0x0<<3)
+#define GAC_ECO_BITS 0x14090
+#define ECOBITS_PPGTT_CACHE64B (3<<8)
+#define ECOBITS_PPGTT_CACHE4B (0<<8)
+
#define GAB_CTL 0x24000
#define GAB_CTL_CONT_AFTER_PAGEFAULT (1<<8)
--
1.7.7.6
