Revert "drm/i915/icl: WaEnableFloatBlendOptimization"

The register for 0xe420 is unable to hold any value, including
this bit. The documentation is also mixed between having a
register bit for toggle and having a state command setup
for it. Apparently the register toggle is deprecated.

Remove the register toggle as evidence shows it's futile.

The thing remaining is an apology and humble request for
Mesa folks to resurrect their state setup for this as they
were on right track from start.

This reverts commit 0bf059f3532bb39c52d917142206a8554fc2f1c5.

Fixes: 0bf059f3532b ("drm/i915/icl: WaEnableFloatBlendOptimization")
References: HSDES#1406393558
Cc: Oscar Mateo <oscar.mateo@intel.com>
Cc: Anuj Phogat <anuj.phogat@gmail.com>
Cc: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Lionel Landwerlin <lionel.g.landwerlin@intel.com>
Signed-off-by: Mika Kuoppala <mika.kuoppala@linux.intel.com>
Acked-by: Chris Wilson <chris@chris-wilson.co.uk>
Link: https://patchwork.freedesktop.org/patch/msgid/20180730120636.26958-1-mika.kuoppala@linux.intel.com

diff --git a/drivers/gpu/drm/i915/i915_reg.h b/drivers/gpu/drm/i915/i915_reg.h
index 7bdc214..e0f5999 100644 (file)
--- a/drivers/gpu/drm/i915/i915_reg.h
+++ b/drivers/gpu/drm/i915/i915_reg.h
@@ -2859,9 +2859,6 @@ enum i915_power_well_id {
 #define   GEN8_4x4_STC_OPTIMIZATION_DISABLE    (1 << 6)
 #define   GEN9_PARTIAL_RESOLVE_IN_VC_DISABLE   (1 << 1)
 
-#define GEN10_CACHE_MODE_SS                    _MMIO(0xe420)
-#define   FLOAT_BLEND_OPTIMIZATION_ENABLE      (1 << 4)
-
 #define GEN6_BLITTER_ECOSKPD   _MMIO(0x221d0)
 #define   GEN6_BLITTER_LOCK_SHIFT                      16
 #define   GEN6_BLITTER_FBC_NOTIFY                      (1 << 3)

diff --git a/drivers/gpu/drm/i915/intel_workarounds.c b/drivers/gpu/drm/i915/intel_workarounds.c
index f8bb32e..4bcdeaf 100644 (file)
--- a/drivers/gpu/drm/i915/intel_workarounds.c
+++ b/drivers/gpu/drm/i915/intel_workarounds.c
@@ -508,9 +508,6 @@ static int icl_ctx_workarounds_init(struct drm_i915_private *dev_priv)
                WA_SET_BIT_MASKED(GEN11_COMMON_SLICE_CHICKEN3,
                                  GEN11_BLEND_EMB_FIX_DISABLE_IN_RCC);
 
-       /* WaEnableFloatBlendOptimization:icl */
-       WA_SET_BIT_MASKED(GEN10_CACHE_MODE_SS, FLOAT_BLEND_OPTIMIZATION_ENABLE);
-
        return 0;
 }