drm/amdgpu: print VCN instance dump for valid instance

VCN dump is dependent on power state of the ip. Dump is
valid if VCN was powered up at the time of ip dump.
Signed-off-by: Sunil Khatri <sunil.khatri@amd.com>
Reviewed-by: Alex Deucher <alexander.deucher@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>

drivers/gpu/drm/amd/amdgpu/vcn_v3_0.c

@@ -2329,7 +2329,7 @@ static void vcn_v3_0_print_ip_state(void *handle, struct drm_printer *p)
 	struct amdgpu_device *adev = (struct amdgpu_device *)handle;
 	int i, j;
 	uint32_t reg_count = ARRAY_SIZE(vcn_reg_list_3_0);
-	uint32_t inst_off;
+	uint32_t inst_off, is_powered;
 
 	if (!adev->vcn.ip_dump)
 		return;
@@ -2342,11 +2342,17 @@ static void vcn_v3_0_print_ip_state(void *handle, struct drm_printer *p)
 		}
 
 		inst_off = i * reg_count;
-		drm_printf(p, "\nActive Instance:VCN%d\n", i);
+		is_powered = (adev->vcn.ip_dump[inst_off] &
+				UVD_POWER_STATUS__UVD_POWER_STATUS_MASK) != 1;
 
-		for (j = 0; j < reg_count; j++)
-			drm_printf(p, "%-50s \t 0x%08x\n", vcn_reg_list_3_0[j].reg_name,
-				   adev->vcn.ip_dump[inst_off + j]);
+		if (is_powered) {
+			drm_printf(p, "\nActive Instance:VCN%d\n", i);
+			for (j = 0; j < reg_count; j++)
+				drm_printf(p, "%-50s \t 0x%08x\n", vcn_reg_list_3_0[j].reg_name,
+					   adev->vcn.ip_dump[inst_off + j]);
+		} else {
+			drm_printf(p, "\nInactive Instance:VCN%d\n", i);
+		}
 	}
 }
 
@@ -2354,7 +2360,7 @@ static void vcn_v3_0_dump_ip_state(void *handle)
 {
 	struct amdgpu_device *adev = (struct amdgpu_device *)handle;
 	int i, j;
-	bool reg_safe;
+	bool is_powered;
 	uint32_t inst_off;
 	uint32_t reg_count = ARRAY_SIZE(vcn_reg_list_3_0);
 
@@ -2366,11 +2372,13 @@ static void vcn_v3_0_dump_ip_state(void *handle)
 			continue;
 
 		inst_off = i * reg_count;
-		reg_safe = (RREG32_SOC15(VCN, i, mmUVD_POWER_STATUS) &
-			    UVD_POWER_STATUS__UVD_POWER_STATUS_MASK) != 1;
+		/* mmUVD_POWER_STATUS is always readable and is first element of the array */
+		adev->vcn.ip_dump[inst_off] = RREG32_SOC15(VCN, i, mmUVD_POWER_STATUS);
+		is_powered = (adev->vcn.ip_dump[inst_off] &
+				UVD_POWER_STATUS__UVD_POWER_STATUS_MASK) != 1;
 
-		if (reg_safe)
-			for (j = 0; j < reg_count; j++)
+		if (is_powered)
+			for (j = 1; j < reg_count; j++)
 				adev->vcn.ip_dump[inst_off + j] =
 					RREG32(SOC15_REG_ENTRY_OFFSET_INST(vcn_reg_list_3_0[j], i));
 	}