diff options
author | Ville Syrjälä <ville.syrjala@linux.intel.com> | 2020-10-15 13:21:37 +0100 |
---|---|---|
committer | Chris Wilson <chris@chris-wilson.co.uk> | 2020-10-15 15:38:20 +0100 |
commit | c0888e9e22623972a8468cd18f4b5b7c6db040ee (patch) | |
tree | 1454794e405bc397cc968667b43fbc7f76cfde3f /drivers/gpu/drm/i915/gt/intel_gtt.c | |
parent | 36b6b6816989cf6f468eea82694e83211a066fa4 (diff) |
drm/i915: Enable eLLC caching of display buffers for SKL+
Since SKL the eLLC has been sitting on the far side of the system
agent, meaning the display engine can utilize it. Let's enable that.
I chose WB for the caching mode, because my numbers are indicating
that WT might actually be WB and WC might actually be UC. I'm not
100% sure that is indeed the case but at least my simple rendercopy
based benchmark didn't see any difference in performance.
Also if I configure things to do LLCeLLC+WT I still get cache dirt
on my screen, suggesting that is in fact operating in WB mode
anyway. This is also the reason I had to fix the MOCS target cache
to really say PTE rather than LLC+eLLC.
Since SKL the eLLC has been sitting on the far side of the system agent,
meaning the display engine can utilize it. Let's enable that.
Eero's earlier benchmarks numbers:
"* Results in GfxBench and Unigine (Valley/Heaven) tests were within daily
variation on the tested SKL machines
* SKL GT4e (128MB eLLC) / Wayland / Weston:
+15-20% SynMark TexMem512 (512MB of textures)
+4-6% SynMark TerrainFly*, CSCloth, ShMapVsm
-5-10% SynMark TexMem128 (128MB of textures)
* SKL GT3e (64MB eLLC) / Xorg / Unity:
+4-8% GpuTest Triangle fullscreen (FullHD)
-5-10% GpuTest Triangle windowed (1/2 screen)
* SKL GT2 (no eLLC) / Xorg / Unity:
* Some of the higher FPS SynMark pixel and vertex shader tests
are few percent higher, more than daily variance
=> Do you see any reason why this machine would be impacted
although it doesn't eLLC?"
Caveats:
- Still haven't tested with a prime setup
- Still not entirely sure this a good idea, but I've been
using it on my cfl anyway :)
v2: Split the MOCS PTE change out
Cc: Eero Tamminen <eero.t.tamminen@intel.com>
Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Link: https://patchwork.freedesktop.org/patch/msgid/20201007120329.17076-3-ville.syrjala@linux.intel.com
Link: https://patchwork.freedesktop.org/patch/msgid/20201015122138.30161-3-chris@chris-wilson.co.uk
Diffstat (limited to 'drivers/gpu/drm/i915/gt/intel_gtt.c')
-rw-r--r-- | drivers/gpu/drm/i915/gt/intel_gtt.c | 10 |
1 files changed, 8 insertions, 2 deletions
diff --git a/drivers/gpu/drm/i915/gt/intel_gtt.c b/drivers/gpu/drm/i915/gt/intel_gtt.c index 3f1114b58b01..7bfe9072be9a 100644 --- a/drivers/gpu/drm/i915/gt/intel_gtt.c +++ b/drivers/gpu/drm/i915/gt/intel_gtt.c @@ -324,7 +324,7 @@ static void cnl_setup_private_ppat(struct intel_uncore *uncore) GEN8_PPAT_WC | GEN8_PPAT_LLCELLC); intel_uncore_write(uncore, GEN10_PAT_INDEX(2), - GEN8_PPAT_WT | GEN8_PPAT_LLCELLC); + GEN8_PPAT_WB | GEN8_PPAT_ELLC_OVERRIDE); intel_uncore_write(uncore, GEN10_PAT_INDEX(3), GEN8_PPAT_UC); @@ -349,17 +349,23 @@ static void cnl_setup_private_ppat(struct intel_uncore *uncore) */ static void bdw_setup_private_ppat(struct intel_uncore *uncore) { + struct drm_i915_private *i915 = uncore->i915; u64 pat; pat = GEN8_PPAT(0, GEN8_PPAT_WB | GEN8_PPAT_LLC) | /* for normal objects, no eLLC */ GEN8_PPAT(1, GEN8_PPAT_WC | GEN8_PPAT_LLCELLC) | /* for something pointing to ptes? */ - GEN8_PPAT(2, GEN8_PPAT_WT | GEN8_PPAT_LLCELLC) | /* for scanout with eLLC */ GEN8_PPAT(3, GEN8_PPAT_UC) | /* Uncached objects, mostly for scanout */ GEN8_PPAT(4, GEN8_PPAT_WB | GEN8_PPAT_LLCELLC | GEN8_PPAT_AGE(0)) | GEN8_PPAT(5, GEN8_PPAT_WB | GEN8_PPAT_LLCELLC | GEN8_PPAT_AGE(1)) | GEN8_PPAT(6, GEN8_PPAT_WB | GEN8_PPAT_LLCELLC | GEN8_PPAT_AGE(2)) | GEN8_PPAT(7, GEN8_PPAT_WB | GEN8_PPAT_LLCELLC | GEN8_PPAT_AGE(3)); + /* for scanout with eLLC */ + if (INTEL_GEN(i915) >= 9) + pat |= GEN8_PPAT(2, GEN8_PPAT_WB | GEN8_PPAT_ELLC_OVERRIDE); + else + pat |= GEN8_PPAT(2, GEN8_PPAT_WT | GEN8_PPAT_LLCELLC); + intel_uncore_write(uncore, GEN8_PRIVATE_PAT_LO, lower_32_bits(pat)); intel_uncore_write(uncore, GEN8_PRIVATE_PAT_HI, upper_32_bits(pat)); } |