drm/radeon: add fault decode function for cayman/TN (v2)

Helpful for debugging GPUVM errors as we can see what
hw block and page generated the fault in the log.

v2: simplify fault decoding

Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
Reviewed-by: Christian König <christian.koenig@amd.com>

drivers/gpu/drm/radeon/evergreen.c

@@ -139,6 +139,8 @@ void evergreen_pcie_gen2_enable(struct radeon_device *rdev);
 void evergreen_program_aspm(struct radeon_device *rdev);
 extern void cayman_cp_int_cntl_setup(struct radeon_device *rdev,
 				     int ring, u32 cp_int_cntl);
+extern void cayman_vm_decode_fault(struct radeon_device *rdev,
+				   u32 status, u32 addr);
 
 static const u32 evergreen_golden_registers[] =
 {
@@ -4586,6 +4588,7 @@ int evergreen_irq_process(struct radeon_device *rdev)
 	bool queue_hotplug = false;
 	bool queue_hdmi = false;
 	bool queue_thermal = false;
+	u32 status, addr;
 
 	if (!rdev->ih.enabled || rdev->shutdown)
 		return IRQ_NONE;
@@ -4872,11 +4875,14 @@ restart_ih:
 			break;
 		case 146:
 		case 147:
+			addr = RREG32(VM_CONTEXT1_PROTECTION_FAULT_ADDR);
+			status = RREG32(VM_CONTEXT1_PROTECTION_FAULT_STATUS);
 			dev_err(rdev->dev, "GPU fault detected: %d 0x%08x\n", src_id, src_data);
 			dev_err(rdev->dev, "  VM_CONTEXT1_PROTECTION_FAULT_ADDR   0x%08X\n",
-				RREG32(VM_CONTEXT1_PROTECTION_FAULT_ADDR));
+				addr);
 			dev_err(rdev->dev, "  VM_CONTEXT1_PROTECTION_FAULT_STATUS 0x%08X\n",
-				RREG32(VM_CONTEXT1_PROTECTION_FAULT_STATUS));
+				status);
+			cayman_vm_decode_fault(rdev, status, addr);
 			/* reset addr and status */
 			WREG32_P(VM_CONTEXT1_CNTL2, 1, ~1);
 			break;

drivers/gpu/drm/radeon/ni.c

@@ -2450,6 +2450,167 @@ void cayman_vm_fini(struct radeon_device *rdev)
 {
 }
 
+/**
+ * cayman_vm_decode_fault - print human readable fault info
+ *
+ * @rdev: radeon_device pointer
+ * @status: VM_CONTEXT1_PROTECTION_FAULT_STATUS register value
+ * @addr: VM_CONTEXT1_PROTECTION_FAULT_ADDR register value
+ *
+ * Print human readable fault information (cayman/TN).
+ */
+void cayman_vm_decode_fault(struct radeon_device *rdev,
+			    u32 status, u32 addr)
+{
+	u32 mc_id = (status & MEMORY_CLIENT_ID_MASK) >> MEMORY_CLIENT_ID_SHIFT;
+	u32 vmid = (status & FAULT_VMID_MASK) >> FAULT_VMID_SHIFT;
+	u32 protections = (status & PROTECTIONS_MASK) >> PROTECTIONS_SHIFT;
+	char *block;
+
+	switch (mc_id) {
+	case 32:
+	case 16:
+	case 96:
+	case 80:
+	case 160:
+	case 144:
+	case 224:
+	case 208:
+		block = "CB";
+		break;
+	case 33:
+	case 17:
+	case 97:
+	case 81:
+	case 161:
+	case 145:
+	case 225:
+	case 209:
+		block = "CB_FMASK";
+		break;
+	case 34:
+	case 18:
+	case 98:
+	case 82:
+	case 162:
+	case 146:
+	case 226:
+	case 210:
+		block = "CB_CMASK";
+		break;
+	case 35:
+	case 19:
+	case 99:
+	case 83:
+	case 163:
+	case 147:
+	case 227:
+	case 211:
+		block = "CB_IMMED";
+		break;
+	case 36:
+	case 20:
+	case 100:
+	case 84:
+	case 164:
+	case 148:
+	case 228:
+	case 212:
+		block = "DB";
+		break;
+	case 37:
+	case 21:
+	case 101:
+	case 85:
+	case 165:
+	case 149:
+	case 229:
+	case 213:
+		block = "DB_HTILE";
+		break;
+	case 38:
+	case 22:
+	case 102:
+	case 86:
+	case 166:
+	case 150:
+	case 230:
+	case 214:
+		block = "SX";
+		break;
+	case 39:
+	case 23:
+	case 103:
+	case 87:
+	case 167:
+	case 151:
+	case 231:
+	case 215:
+		block = "DB_STEN";
+		break;
+	case 40:
+	case 24:
+	case 104:
+	case 88:
+	case 232:
+	case 216:
+	case 168:
+	case 152:
+		block = "TC_TFETCH";
+		break;
+	case 41:
+	case 25:
+	case 105:
+	case 89:
+	case 233:
+	case 217:
+	case 169:
+	case 153:
+		block = "TC_VFETCH";
+		break;
+	case 42:
+	case 26:
+	case 106:
+	case 90:
+	case 234:
+	case 218:
+	case 170:
+	case 154:
+		block = "VC";
+		break;
+	case 112:
+		block = "CP";
+		break;
+	case 113:
+	case 114:
+		block = "SH";
+		break;
+	case 115:
+		block = "VGT";
+		break;
+	case 178:
+		block = "IH";
+		break;
+	case 51:
+		block = "RLC";
+		break;
+	case 55:
+		block = "DMA";
+		break;
+	case 56:
+		block = "HDP";
+		break;
+	default:
+		block = "unknown";
+		break;
+	}
+
+	printk("VM fault (0x%02x, vmid %d) at page %u, %s from %s (%d)\n",
+	       protections, vmid, addr,
+	       (status & MEMORY_CLIENT_RW_MASK) ? "write" : "read",
+	       block, mc_id);
+}
+
 #define R600_ENTRY_VALID   (1 << 0)
 #define R600_PTE_SYSTEM    (1 << 1)
 #define R600_PTE_SNOOPED   (1 << 2)

drivers/gpu/drm/radeon/nid.h

@@ -133,6 +133,22 @@
 #define VM_CONTEXT1_CNTL2				0x1434
 #define VM_INVALIDATE_REQUEST				0x1478
 #define VM_INVALIDATE_RESPONSE				0x147c
+#define	VM_CONTEXT1_PROTECTION_FAULT_ADDR		0x14FC
+#define	VM_CONTEXT1_PROTECTION_FAULT_STATUS		0x14DC
+#define		PROTECTIONS_MASK			(0xf << 0)
+#define		PROTECTIONS_SHIFT			0
+		/* bit 0: range
+		 * bit 2: pde0
+		 * bit 3: valid
+		 * bit 4: read
+		 * bit 5: write
+		 */
+#define		MEMORY_CLIENT_ID_MASK			(0xff << 12)
+#define		MEMORY_CLIENT_ID_SHIFT			12
+#define		MEMORY_CLIENT_RW_MASK			(1 << 24)
+#define		MEMORY_CLIENT_RW_SHIFT			24
+#define		FAULT_VMID_MASK				(0x7 << 25)
+#define		FAULT_VMID_SHIFT			25
 #define VM_CONTEXT0_PROTECTION_FAULT_DEFAULT_ADDR	0x1518
 #define VM_CONTEXT1_PROTECTION_FAULT_DEFAULT_ADDR	0x151c
 #define	VM_CONTEXT0_PAGE_TABLE_BASE_ADDR		0x153C