drm/i915: Switch over to the LLC/eLLC hotspot avoidance hash mode for CCS

Use the LLC/eLLC hotspot avoidance mode for CCS on LLC machines. This is
reported to give better performance.

Testing has indicated that we don't need to enforce any massive 2 or 4
MiB alignment for all compressed resources even though there are still
plenty of stale comments in the spec suggesting that we do.

We do need to make sure every hardware unit that deals with the
compressed data uses the same hash mode.

Cc: Ben Widawsky <ben@bwidawsk.net>
Cc: Jason Ekstrand <jason@jlekstrand.net>
Cc: Daniel Stone <daniels@collabora.com>
Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20170824191100.10949-4-ville.syrjala@linux.intel.comReviewed-by: Ben Widawsky <ben@bwidawsk.net>

drivers/gpu/drm/i915/i915_reg.h

@@ -6913,7 +6913,7 @@ enum {
 # define CHICKEN3_DGMG_DONE_FIX_DISABLE		(1 << 2)
 
 #define CHICKEN_PAR1_1		_MMIO(0x42080)
-#define  SKL_RC_HASH_OUTSIDE	(1 << 15)
+#define  SKL_DE_COMPRESSED_HASH_MODE	(1 << 15)
 #define  DPA_MASK_VBLANK_SRD	(1 << 15)
 #define  FORCE_ARB_IDLE_PLANES	(1 << 14)
 #define  SKL_EDP_PSR_FIX_RDWRAP	(1 << 3)
@@ -6991,6 +6991,7 @@ enum {
 # define GEN7_CSC1_RHWO_OPT_DISABLE_IN_RCC	((1<<10) | (1<<26))
 # define GEN9_RHWO_OPTIMIZATION_DISABLE		(1<<14)
 #define COMMON_SLICE_CHICKEN2			_MMIO(0x7014)
+# define GEN9_PBE_COMPRESSED_HASH_SELECTION	(1<<13)
 # define GEN9_DISABLE_GATHER_AT_SET_SHADER_COMMON_SLICE (1<<12)
 # define GEN8_SBE_DISABLE_REPLAY_BUF_OPTIMIZATION (1<<8)
 # define GEN8_CSC2_SBE_VUE_CACHE_CONSERVATIVE	(1<<0)
@@ -8085,6 +8086,7 @@ enum {
 #define   GEN8_SAMPLER_POWER_BYPASS_DIS	(1<<1)
 
 #define GEN9_HALF_SLICE_CHICKEN7	_MMIO(0xe194)
+#define   GEN9_SAMPLER_HASH_COMPRESSED_READ_ADDR	(1<<8)
 #define   GEN9_ENABLE_YV12_BUGFIX	(1<<4)
 #define   GEN9_ENABLE_GPGPU_PREEMPTION	(1<<2)
 
@@ -9385,4 +9387,8 @@ enum skl_power_gate {
 #define   GEN9_L3_LRA_1_GPGPU_DEFAULT_VALUE_SKL  0x67F1427F /*    "        " */
 #define   GEN9_L3_LRA_1_GPGPU_DEFAULT_VALUE_BXT  0x5FF101FF /*    "        " */
 
+#define MMCD_MISC_CTRL		_MMIO(0x4ddc) /* skl+ */
+#define  MMCD_PCLA		(1 << 31)
+#define  MMCD_HOTSPOT_EN	(1 << 27)
+
 #endif /* _I915_REG_H_ */

drivers/gpu/drm/i915/intel_engine_cs.c

@@ -938,6 +938,19 @@ static int gen9_init_workarounds(struct intel_engine_cs *engine)
 		I915_WRITE(GAM_ECOCHK, I915_READ(GAM_ECOCHK) |
 			   ECOCHK_DIS_TLB);
 
+	if (HAS_LLC(dev_priv)) {
+		/* WaCompressedResourceSamplerPbeMediaNewHashMode:skl,kbl
+		 *
+		 * Must match Display Engine. See
+		 * WaCompressedResourceDisplayNewHashMode.
+		 */
+		WA_SET_BIT_MASKED(COMMON_SLICE_CHICKEN2,
+				  GEN9_PBE_COMPRESSED_HASH_SELECTION);
+		WA_SET_BIT_MASKED(GEN9_HALF_SLICE_CHICKEN7,
+				  GEN9_SAMPLER_HASH_COMPRESSED_READ_ADDR);
+		WA_SET_BIT(MMCD_MISC_CTRL, MMCD_PCLA | MMCD_HOTSPOT_EN);
+	}
+
 	/* WaClearFlowControlGpgpuContextSave:skl,bxt,kbl,glk,cfl */
 	/* WaDisablePartialInstShootdown:skl,bxt,kbl,glk,cfl */
 	WA_SET_BIT_MASKED(GEN8_ROW_CHICKEN,

drivers/gpu/drm/i915/intel_pm.c

@@ -58,24 +58,23 @@
 
 static void gen9_init_clock_gating(struct drm_i915_private *dev_priv)
 {
+	if (HAS_LLC(dev_priv)) {
+		/*
+		 * WaCompressedResourceDisplayNewHashMode:skl,kbl
+		 * Display WA#0390: skl,kbl
+		 *
+		 * Must match Sampler, Pixel Back End, and Media. See
+		 * WaCompressedResourceSamplerPbeMediaNewHashMode.
+		 */
+		I915_WRITE(CHICKEN_PAR1_1,
+			   I915_READ(CHICKEN_PAR1_1) |
+			   SKL_DE_COMPRESSED_HASH_MODE);
+	}
+
 	/* See Bspec note for PSR2_CTL bit 31, Wa#828:skl,bxt,kbl,cfl */
 	I915_WRITE(CHICKEN_PAR1_1,
 		   I915_READ(CHICKEN_PAR1_1) | SKL_EDP_PSR_FIX_RDWRAP);
 
-	/*
-	 * Display WA#0390: skl,bxt,kbl,glk
-	 *
-	 * Must match Sampler, Pixel Back End, and Media
-	 * (0xE194 bit 8, 0x7014 bit 13, 0x4DDC bits 27 and 31).
-	 *
-	 * Including bits outside the page in the hash would
-	 * require 2 (or 4?) MiB alignment of resources. Just
-	 * assume the defaul hashing mode which only uses bits
-	 * within the page.
-	 */
-	I915_WRITE(CHICKEN_PAR1_1,
-		   I915_READ(CHICKEN_PAR1_1) & ~SKL_RC_HASH_OUTSIDE);
-
 	I915_WRITE(GEN8_CONFIG0,
 		   I915_READ(GEN8_CONFIG0) | GEN9_DEFAULT_FIXES);