diff --git a/drivers/gpu/drm/i915/gt/intel_engine_cs.c b/drivers/gpu/drm/i915/gt/intel_engine_cs.c
index cc4d1826173d..65cbf1d9118d 100644
--- a/drivers/gpu/drm/i915/gt/intel_engine_cs.c
+++ b/drivers/gpu/drm/i915/gt/intel_engine_cs.c
@@ -959,30 +959,6 @@ const char *i915_cache_level_str(struct drm_i915_private *i915, int type)
 	}
 }
 
-u32 intel_calculate_mcr_s_ss_select(struct drm_i915_private *dev_priv)
-{
-	const struct sseu_dev_info *sseu = &RUNTIME_INFO(dev_priv)->sseu;
-	unsigned int slice = fls(sseu->slice_mask) - 1;
-	unsigned int subslice;
-	u32 mcr_s_ss_select;
-
-	GEM_BUG_ON(slice >= ARRAY_SIZE(sseu->subslice_mask));
-	subslice = fls(sseu->subslice_mask[slice]);
-	GEM_BUG_ON(!subslice);
-	subslice--;
-
-	if (IS_GEN(dev_priv, 10))
-		mcr_s_ss_select = GEN8_MCR_SLICE(slice) |
-				  GEN8_MCR_SUBSLICE(subslice);
-	else if (INTEL_GEN(dev_priv) >= 11)
-		mcr_s_ss_select = GEN11_MCR_SLICE(slice) |
-				  GEN11_MCR_SUBSLICE(subslice);
-	else
-		mcr_s_ss_select = 0;
-
-	return mcr_s_ss_select;
-}
-
 static u32
 read_subslice_reg(struct intel_engine_cs *engine, int slice, int subslice,
 		  i915_reg_t reg)
diff --git a/drivers/gpu/drm/i915/gt/intel_workarounds.c b/drivers/gpu/drm/i915/gt/intel_workarounds.c
index 3b1fc7c8faa8..c2325b7ecf8d 100644
--- a/drivers/gpu/drm/i915/gt/intel_workarounds.c
+++ b/drivers/gpu/drm/i915/gt/intel_workarounds.c
@@ -762,7 +762,10 @@ static void
 wa_init_mcr(struct drm_i915_private *i915, struct i915_wa_list *wal)
 {
 	const struct sseu_dev_info *sseu = &RUNTIME_INFO(i915)->sseu;
-	u32 mcr_slice_subslice_mask;
+	unsigned int slice, subslice;
+	u32 l3_en, mcr, mcr_mask;
+
+	GEM_BUG_ON(INTEL_GEN(i915) < 10);
 
 	/*
 	 * WaProgramMgsrForL3BankSpecificMmioReads: cnl,icl
@@ -770,42 +773,7 @@ wa_init_mcr(struct drm_i915_private *i915, struct i915_wa_list *wal)
 	 * the case, we might need to program MCR select to a valid L3Bank
 	 * by default, to make sure we correctly read certain registers
 	 * later on (in the range 0xB100 - 0xB3FF).
-	 * This might be incompatible with
-	 * WaProgramMgsrForCorrectSliceSpecificMmioReads.
-	 * Fortunately, this should not happen in production hardware, so
-	 * we only assert that this is the case (instead of implementing
-	 * something more complex that requires checking the range of every
-	 * MMIO read).
-	 */
-	if (INTEL_GEN(i915) >= 10 &&
-	    is_power_of_2(sseu->slice_mask)) {
-		/*
-		 * read FUSE3 for enabled L3 Bank IDs, if L3 Bank matches
-		 * enabled subslice, no need to redirect MCR packet
-		 */
-		u32 slice = fls(sseu->slice_mask);
-		u32 fuse3 =
-			intel_uncore_read(&i915->uncore, GEN10_MIRROR_FUSE3);
-		u8 ss_mask = sseu->subslice_mask[slice];
-
-		u8 enabled_mask = (ss_mask | ss_mask >>
-				   GEN10_L3BANK_PAIR_COUNT) & GEN10_L3BANK_MASK;
-		u8 disabled_mask = fuse3 & GEN10_L3BANK_MASK;
-
-		/*
-		 * Production silicon should have matched L3Bank and
-		 * subslice enabled
-		 */
-		WARN_ON((enabled_mask & disabled_mask) != enabled_mask);
-	}
-
-	if (INTEL_GEN(i915) >= 11)
-		mcr_slice_subslice_mask = GEN11_MCR_SLICE_MASK |
-					  GEN11_MCR_SUBSLICE_MASK;
-	else
-		mcr_slice_subslice_mask = GEN8_MCR_SLICE_MASK |
-					  GEN8_MCR_SUBSLICE_MASK;
-	/*
+	 *
 	 * WaProgramMgsrForCorrectSliceSpecificMmioReads:cnl,icl
 	 * Before any MMIO read into slice/subslice specific registers, MCR
 	 * packet control register needs to be programmed to point to any
@@ -815,11 +783,51 @@ wa_init_mcr(struct drm_i915_private *i915, struct i915_wa_list *wal)
 	 * are consistent across s/ss in almost all cases. In the rare
 	 * occasions, such as INSTDONE, where this value is dependent
 	 * on s/ss combo, the read should be done with read_subslice_reg.
+	 *
+	 * Since GEN8_MCR_SELECTOR contains dual-purpose bits which select both
+	 * to which subslice, or to which L3 bank, the respective mmio reads
+	 * will go, we have to find a common index which works for both
+	 * accesses.
+	 *
+	 * Case where we cannot find a common index fortunately should not
+	 * happen in production hardware, so we only emit a warning instead of
+	 * implementing something more complex that requires checking the range
+	 * of every MMIO read.
 	 */
-	wa_write_masked_or(wal,
-			   GEN8_MCR_SELECTOR,
-			   mcr_slice_subslice_mask,
-			   intel_calculate_mcr_s_ss_select(i915));
+
+	if (INTEL_GEN(i915) >= 10 && is_power_of_2(sseu->slice_mask)) {
+		u32 l3_fuse =
+			intel_uncore_read(&i915->uncore, GEN10_MIRROR_FUSE3) &
+			GEN10_L3BANK_MASK;
+
+		DRM_DEBUG_DRIVER("L3 fuse = %x\n", l3_fuse);
+		l3_en = ~(l3_fuse << GEN10_L3BANK_PAIR_COUNT | l3_fuse);
+	} else {
+		l3_en = ~0;
+	}
+
+	slice = fls(sseu->slice_mask) - 1;
+	GEM_BUG_ON(slice >= ARRAY_SIZE(sseu->subslice_mask));
+	subslice = fls(l3_en & sseu->subslice_mask[slice]);
+	if (!subslice) {
+		DRM_WARN("No common index found between subslice mask %x and L3 bank mask %x!\n",
+			 sseu->subslice_mask[slice], l3_en);
+		subslice = fls(l3_en);
+		WARN_ON(!subslice);
+	}
+	subslice--;
+
+	if (INTEL_GEN(i915) >= 11) {
+		mcr = GEN11_MCR_SLICE(slice) | GEN11_MCR_SUBSLICE(subslice);
+		mcr_mask = GEN11_MCR_SLICE_MASK | GEN11_MCR_SUBSLICE_MASK;
+	} else {
+		mcr = GEN8_MCR_SLICE(slice) | GEN8_MCR_SUBSLICE(subslice);
+		mcr_mask = GEN8_MCR_SLICE_MASK | GEN8_MCR_SUBSLICE_MASK;
+	}
+
+	DRM_DEBUG_DRIVER("MCR slice/subslice = %x\n", mcr);
+
+	wa_write_masked_or(wal, GEN8_MCR_SELECTOR, mcr_mask, mcr);
 }
 
 static void
diff --git a/drivers/gpu/drm/i915/i915_drv.h b/drivers/gpu/drm/i915/i915_drv.h
index a86a6ea3849f..1a58fb8c88c2 100644
--- a/drivers/gpu/drm/i915/i915_drv.h
+++ b/drivers/gpu/drm/i915/i915_drv.h
@@ -2389,8 +2389,6 @@ void i915_driver_remove(struct drm_device *dev);
 void intel_engine_init_hangcheck(struct intel_engine_cs *engine);
 int vlv_force_gfx_clock(struct drm_i915_private *dev_priv, bool on);
 
-u32 intel_calculate_mcr_s_ss_select(struct drm_i915_private *dev_priv);
-
 static inline bool intel_gvt_active(struct drm_i915_private *dev_priv)
 {
 	return dev_priv->gvt;