drm/i915/perf: Add Wa_1508761755:dg2

Disable Clock gating in EU when gathering the events so that EU events
are not lost.

v2: Fix checkpatch issues
v3: User MCR helpers to write to MC reg
v4: Indent correctly (checkpatch)
Signed-off-by: Umesh Nerlige Ramappa <umesh.nerlige.ramappa@intel.com>
Reviewed-by: Ashutosh Dixit <ashutosh.dixit@intel.com>
Signed-off-by: John Harrison <John.C.Harrison@Intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20221026222102.5526-12-umesh.nerlige.ramappa@intel.com

drivers/gpu/drm/i915/gt/intel_gt_regs.h

@@ -1162,6 +1162,7 @@
 #define   GEN12_DISABLE_EARLY_READ		REG_BIT(14)
 #define   GEN12_ENABLE_LARGE_GRF_MODE		REG_BIT(12)
 #define   GEN12_PUSH_CONST_DEREF_HOLD_DIS	REG_BIT(8)
+#define   GEN12_DISABLE_DOP_GATING              REG_BIT(0)
 
 #define RT_CTRL					MCR_REG(0xe530)
 #define   DIS_NULL_QUERY			REG_BIT(10)

drivers/gpu/drm/i915/i915_perf.c

@@ -204,6 +204,7 @@
 #include "gt/intel_gpu_commands.h"
 #include "gt/intel_gt.h"
 #include "gt/intel_gt_clock_utils.h"
+#include "gt/intel_gt_mcr.h"
 #include "gt/intel_gt_regs.h"
 #include "gt/intel_lrc.h"
 #include "gt/intel_lrc_reg.h"
@@ -2775,6 +2776,18 @@ gen12_enable_metric_set(struct i915_perf_stream *stream,
 	u32 sqcnt1;
 	int ret;
 
+	/*
+	 * Wa_1508761755:xehpsdv, dg2
+	 * EU NOA signals behave incorrectly if EU clock gating is enabled.
+	 * Disable thread stall DOP gating and EU DOP gating.
+	 */
+	if (IS_XEHPSDV(i915) || IS_DG2(i915)) {
+		intel_gt_mcr_multicast_write(uncore->gt, GEN8_ROW_CHICKEN,
+					     _MASKED_BIT_ENABLE(STALL_DOP_GATING_DISABLE));
+		intel_uncore_write(uncore, GEN7_ROW_CHICKEN2,
+				   _MASKED_BIT_ENABLE(GEN12_DISABLE_DOP_GATING));
+	}
+
 	intel_uncore_write(uncore, GEN12_OAG_OA_DEBUG,
 			   /* Disable clk ratio reports, like previous Gens. */
 			   _MASKED_BIT_ENABLE(GEN12_OAG_OA_DEBUG_DISABLE_CLK_RATIO_REPORTS |
@@ -2853,6 +2866,17 @@ static void gen12_disable_metric_set(struct i915_perf_stream *stream)
 	struct drm_i915_private *i915 = stream->perf->i915;
 	u32 sqcnt1;
 
+	/*
+	 * Wa_1508761755:xehpsdv, dg2
+	 * Enable thread stall DOP gating and EU DOP gating.
+	 */
+	if (IS_XEHPSDV(i915) || IS_DG2(i915)) {
+		intel_gt_mcr_multicast_write(uncore->gt, GEN8_ROW_CHICKEN,
+					     _MASKED_BIT_DISABLE(STALL_DOP_GATING_DISABLE));
+		intel_uncore_write(uncore, GEN7_ROW_CHICKEN2,
+				   _MASKED_BIT_DISABLE(GEN12_DISABLE_DOP_GATING));
+	}
+
 	/* Reset all contexts' slices/subslices configurations. */
 	gen12_configure_all_contexts(stream, NULL, NULL);