On Fri, 22 Nov 2013 10:37:53 +0000 Chris Wilson <chris@xxxxxxxxxxxxxxxxxx> wrote: > We have conflicting benchmark data that suggest either age 0 or age 3 is > better. However, the earlier benchmark on which we based the switch to > age 0 > > (commit 0d8ff15e9a15f2b393e53337a107b7a1e5919b6d > Author: Ben Widawsky <benjamin.widawsky@xxxxxxxxx> > Date: Thu Jul 4 11:02:03 2013 -0700 > > drm/i915/hsw: Set correct Haswell PTE encodings) > > actually seems to prefer the default PTE encoding as age 3. Presumably, > this is in part due to the use of MOCS to override the PTE encodings > when appropriate. > > Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=69870 > Tested-by: mengmeng.meng@xxxxxxxxx > Signed-off-by: Chris Wilson <chris@xxxxxxxxxxxxxxxxxx> > --- > drivers/gpu/drm/i915/i915_gem_gtt.c | 6 ++++-- > 1 file changed, 4 insertions(+), 2 deletions(-) > > diff --git a/drivers/gpu/drm/i915/i915_gem_gtt.c b/drivers/gpu/drm/i915/i915_gem_gtt.c > index efb5dab61c81..c4a3f9ae0d43 100644 > --- a/drivers/gpu/drm/i915/i915_gem_gtt.c > +++ b/drivers/gpu/drm/i915/i915_gem_gtt.c > @@ -57,7 +57,9 @@ typedef gen8_gtt_pte_t gen8_ppgtt_pde_t; > #define HSW_WB_LLC_AGE3 HSW_CACHEABILITY_CONTROL(0x2) > #define HSW_WB_LLC_AGE0 HSW_CACHEABILITY_CONTROL(0x3) > #define HSW_WB_ELLC_LLC_AGE0 HSW_CACHEABILITY_CONTROL(0xb) > +#define HSW_WB_ELLC_LLC_AGE3 HSW_CACHEABILITY_CONTROL(0x8) > #define HSW_WT_ELLC_LLC_AGE0 HSW_CACHEABILITY_CONTROL(0x6) > +#define HSW_WT_ELLC_LLC_AGE3 HSW_CACHEABILITY_CONTROL(0x7) > > #define GEN8_PTES_PER_PAGE (PAGE_SIZE / sizeof(gen8_gtt_pte_t)) > #define GEN8_PDES_PER_PAGE (PAGE_SIZE / sizeof(gen8_ppgtt_pde_t)) > @@ -185,10 +187,10 @@ static gen6_gtt_pte_t iris_pte_encode(dma_addr_t addr, > case I915_CACHE_NONE: > break; > case I915_CACHE_WT: > - pte |= HSW_WT_ELLC_LLC_AGE0; > + pte |= HSW_WT_ELLC_LLC_AGE3; > break; > default: > - pte |= HSW_WB_ELLC_LLC_AGE0; > + pte |= HSW_WB_ELLC_LLC_AGE3; > break; > } > Yeah I guess as long as userspace can override the default with MOCS, this is fine. Acked-by: Jesse Barnes <jbarnes@xxxxxxxxxxxxxxxx> -- Jesse Barnes, Intel Open Source Technology Center _______________________________________________ Intel-gfx mailing list Intel-gfx@xxxxxxxxxxxxxxxxxxxxx http://lists.freedesktop.org/mailman/listinfo/intel-gfx