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. v2: Fixup rebase fail. Reviewed-by: Ben Widawsky <ben at bwidawsk.net> Signed-Off-by: Daniel Vetter <daniel.vetter at ffwll.ch> --- drivers/gpu/drm/i915/i915_gem.c | 5 ++++- drivers/gpu/drm/i915/i915_reg.h | 4 ++++ 2 files changed, 8 insertions(+), 1 deletions(-) diff --git a/drivers/gpu/drm/i915/i915_gem.c b/drivers/gpu/drm/i915/i915_gem.c index 5e0d7d4..dc2478c 100644 --- a/drivers/gpu/drm/i915/i915_gem.c +++ b/drivers/gpu/drm/i915/i915_gem.c @@ -3787,7 +3787,10 @@ void i915_gem_init_ppgtt(struct drm_device *dev) pd_offset <<= 16; if (INTEL_INFO(dev)->gen == 6) { - uint32_t ecochk, gab_ctl; + 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 9aeee7a..78171f7 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