drm/i915/xehp: Check for faults on primary GAM

On Xe_HP the fault registers are now in a multicast register range.
However as part of the GAM these registers follow special rules and we
need only read from the "primary" GAM's instance to get the information
we need.  So a single intel_gt_mcr_read_any() (which will automatically
steer to the primary GAM) is sufficient; we don't need to loop over each
instance of the MCR register.

v2:
 - Update more instances of fault registers.  (Bala)

Signed-off-by: Matt Roper <matthew.d.roper@intel.com>
Reviewed-by: Balasubramani Vivekanandan <balasubramani.vivekanandan@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20221014230239.1023689-7-matthew.d.roper@intel.com

drivers/gpu/drm/i915/gt/intel_gt.c

@@ -270,7 +270,11 @@ intel_gt_clear_error_registers(struct intel_gt *gt,
 				   I915_MASTER_ERROR_INTERRUPT);
 	}
 
-	if (GRAPHICS_VER(i915) >= 12) {
+	if (GRAPHICS_VER_FULL(i915) >= IP_VER(12, 50)) {
+		intel_gt_mcr_multicast_rmw(gt, XEHP_RING_FAULT_REG,
+					   RING_FAULT_VALID, 0);
+		intel_gt_mcr_read_any(gt, XEHP_RING_FAULT_REG);
+	} else if (GRAPHICS_VER(i915) >= 12) {
 		rmw_clear(uncore, GEN12_RING_FAULT_REG, RING_FAULT_VALID);
 		intel_uncore_posting_read(uncore, GEN12_RING_FAULT_REG);
 	} else if (GRAPHICS_VER(i915) >= 8) {
@@ -308,17 +312,49 @@ static void gen6_check_faults(struct intel_gt *gt)
 	}
 }
 
+static void xehp_check_faults(struct intel_gt *gt)
+{
+	u32 fault;
+
+	/*
+	 * Although the fault register now lives in an MCR register range,
+	 * the GAM registers are special and we only truly need to read
+	 * the "primary" GAM instance rather than handling each instance
+	 * individually.  intel_gt_mcr_read_any() will automatically steer
+	 * toward the primary instance.
+	 */
+	fault = intel_gt_mcr_read_any(gt, XEHP_RING_FAULT_REG);
+	if (fault & RING_FAULT_VALID) {
+		u32 fault_data0, fault_data1;
+		u64 fault_addr;
+
+		fault_data0 = intel_gt_mcr_read_any(gt, XEHP_FAULT_TLB_DATA0);
+		fault_data1 = intel_gt_mcr_read_any(gt, XEHP_FAULT_TLB_DATA1);
+
+		fault_addr = ((u64)(fault_data1 & FAULT_VA_HIGH_BITS) << 44) |
+			     ((u64)fault_data0 << 12);
+
+		drm_dbg(&gt->i915->drm, "Unexpected fault\n"
+			"\tAddr: 0x%08x_%08x\n"
+			"\tAddress space: %s\n"
+			"\tEngine ID: %d\n"
+			"\tSource ID: %d\n"
+			"\tType: %d\n",
+			upper_32_bits(fault_addr), lower_32_bits(fault_addr),
+			fault_data1 & FAULT_GTT_SEL ? "GGTT" : "PPGTT",
+			GEN8_RING_FAULT_ENGINE_ID(fault),
+			RING_FAULT_SRCID(fault),
+			RING_FAULT_FAULT_TYPE(fault));
+	}
+}
+
 static void gen8_check_faults(struct intel_gt *gt)
 {
 	struct intel_uncore *uncore = gt->uncore;
 	i915_reg_t fault_reg, fault_data0_reg, fault_data1_reg;
 	u32 fault;
 
-	if (GRAPHICS_VER_FULL(gt->i915) >= IP_VER(12, 50)) {
-		fault_reg = XEHP_RING_FAULT_REG;
-		fault_data0_reg = XEHP_FAULT_TLB_DATA0;
-		fault_data1_reg = XEHP_FAULT_TLB_DATA1;
-	} else if (GRAPHICS_VER(gt->i915) >= 12) {
+	if (GRAPHICS_VER(gt->i915) >= 12) {
 		fault_reg = GEN12_RING_FAULT_REG;
 		fault_data0_reg = GEN12_FAULT_TLB_DATA0;
 		fault_data1_reg = GEN12_FAULT_TLB_DATA1;
@@ -358,7 +394,9 @@ void intel_gt_check_and_clear_faults(struct intel_gt *gt)
 	struct drm_i915_private *i915 = gt->i915;
 
 	/* From GEN8 onwards we only have one 'All Engine Fault Register' */
-	if (GRAPHICS_VER(i915) >= 8)
+	if (GRAPHICS_VER_FULL(i915) >= IP_VER(12, 50))
+		xehp_check_faults(gt);
+	else if (GRAPHICS_VER(i915) >= 8)
 		gen8_check_faults(gt);
 	else if (GRAPHICS_VER(i915) >= 6)
 		gen6_check_faults(gt);

drivers/gpu/drm/i915/i915_gpu_error.c

@@ -1221,7 +1221,10 @@ static void engine_record_registers(struct intel_engine_coredump *ee)
 	if (GRAPHICS_VER(i915) >= 6) {
 		ee->rc_psmi = ENGINE_READ(engine, RING_PSMI_CTL);
 
-		if (GRAPHICS_VER(i915) >= 12)
+		if (GRAPHICS_VER_FULL(i915) >= IP_VER(12, 50))
+			ee->fault_reg = intel_gt_mcr_read_any(engine->gt,
+							      XEHP_RING_FAULT_REG);
+		else if (GRAPHICS_VER(i915) >= 12)
 			ee->fault_reg = intel_uncore_read(engine->uncore,
 							  GEN12_RING_FAULT_REG);
 		else if (GRAPHICS_VER(i915) >= 8)
@@ -1820,7 +1823,12 @@ static void gt_record_global_regs(struct intel_gt_coredump *gt)
 	if (GRAPHICS_VER(i915) == 7)
 		gt->err_int = intel_uncore_read(uncore, GEN7_ERR_INT);
 
-	if (GRAPHICS_VER(i915) >= 12) {
+	if (GRAPHICS_VER_FULL(i915) >= IP_VER(12, 50)) {
+		gt->fault_data0 = intel_gt_mcr_read_any((struct intel_gt *)gt->_gt,
+							XEHP_FAULT_TLB_DATA0);
+		gt->fault_data1 = intel_gt_mcr_read_any((struct intel_gt *)gt->_gt,
+							XEHP_FAULT_TLB_DATA1);
+	} else if (GRAPHICS_VER(i915) >= 12) {
 		gt->fault_data0 = intel_uncore_read(uncore,
 						    GEN12_FAULT_TLB_DATA0);
 		gt->fault_data1 = intel_uncore_read(uncore,