drm/radeon: gcc fixes for extended dpm tables

Newer versions of gcc seem to wander off into the
weeds when dealing with variable sizes arrays in
structs.  Rather than indexing the arrays, use
pointer arithmetic.

See bugs:
https://bugs.freedesktop.org/show_bug.cgi?id=66932
https://bugs.freedesktop.org/show_bug.cgi?id=66972
https://bugs.freedesktop.org/show_bug.cgi?id=66945

Signed-off-by: Alex Deucher <alexander.deucher@amd.com>

drivers/gpu/drm/radeon/r600_dpm.c

@@ -799,15 +799,19 @@ static int r600_parse_clk_voltage_dep_table(struct radeon_clock_voltage_dependen
 	u32 size = atom_table->ucNumEntries *
 		sizeof(struct radeon_clock_voltage_dependency_entry);
 	int i;
+	ATOM_PPLIB_Clock_Voltage_Dependency_Record *entry;
 
 	radeon_table->entries = kzalloc(size, GFP_KERNEL);
 	if (!radeon_table->entries)
 		return -ENOMEM;
 
+	entry = &atom_table->entries[0];
 	for (i = 0; i < atom_table->ucNumEntries; i++) {
-		radeon_table->entries[i].clk = le16_to_cpu(atom_table->entries[i].usClockLow) |
-			(atom_table->entries[i].ucClockHigh << 16);
-		radeon_table->entries[i].v = le16_to_cpu(atom_table->entries[i].usVoltage);
+		radeon_table->entries[i].clk = le16_to_cpu(entry->usClockLow) |
+			(entry->ucClockHigh << 16);
+		radeon_table->entries[i].v = le16_to_cpu(entry->usVoltage);
+		entry = (ATOM_PPLIB_Clock_Voltage_Dependency_Record *)
+			((u8 *)entry + sizeof(ATOM_PPLIB_Clock_Voltage_Dependency_Record));
 	}
 	radeon_table->count = atom_table->ucNumEntries;
 
@@ -931,6 +935,7 @@ int r600_parse_extended_power_table(struct radeon_device *rdev)
 				(ATOM_PPLIB_PhaseSheddingLimits_Table *)
 				(mode_info->atom_context->bios + data_offset +
 				 le16_to_cpu(power_info->pplib4.usVddcPhaseShedLimitsTableOffset));
+			ATOM_PPLIB_PhaseSheddingLimits_Record *entry;
 
 			rdev->pm.dpm.dyn_state.phase_shedding_limits_table.entries =
 				kzalloc(psl->ucNumEntries *
@@ -941,15 +946,16 @@ int r600_parse_extended_power_table(struct radeon_device *rdev)
 				return -ENOMEM;
 			}
 
+			entry = &psl->entries[0];
 			for (i = 0; i < psl->ucNumEntries; i++) {
 				rdev->pm.dpm.dyn_state.phase_shedding_limits_table.entries[i].sclk =
-					le16_to_cpu(psl->entries[i].usSclkLow) |
-					(psl->entries[i].ucSclkHigh << 16);
+					le16_to_cpu(entry->usSclkLow) | (entry->ucSclkHigh << 16);
 				rdev->pm.dpm.dyn_state.phase_shedding_limits_table.entries[i].mclk =
-					le16_to_cpu(psl->entries[i].usMclkLow) |
-					(psl->entries[i].ucMclkHigh << 16);
+					le16_to_cpu(entry->usMclkLow) | (entry->ucMclkHigh << 16);
 				rdev->pm.dpm.dyn_state.phase_shedding_limits_table.entries[i].voltage =
-					le16_to_cpu(psl->entries[i].usVoltage);
+					le16_to_cpu(entry->usVoltage);
+				entry = (ATOM_PPLIB_PhaseSheddingLimits_Record *)
+					((u8 *)entry + sizeof(ATOM_PPLIB_PhaseSheddingLimits_Record));
 			}
 			rdev->pm.dpm.dyn_state.phase_shedding_limits_table.count =
 				psl->ucNumEntries;
@@ -976,26 +982,30 @@ int r600_parse_extended_power_table(struct radeon_device *rdev)
 				(ATOM_PPLIB_CAC_Leakage_Table *)
 				(mode_info->atom_context->bios + data_offset +
 				 le16_to_cpu(power_info->pplib5.usCACLeakageTableOffset));
+			ATOM_PPLIB_CAC_Leakage_Record *entry;
 			u32 size = cac_table->ucNumEntries * sizeof(struct radeon_cac_leakage_table);
 			rdev->pm.dpm.dyn_state.cac_leakage_table.entries = kzalloc(size, GFP_KERNEL);
 			if (!rdev->pm.dpm.dyn_state.cac_leakage_table.entries) {
 				r600_free_extended_power_table(rdev);
 				return -ENOMEM;
 			}
+			entry = &cac_table->entries[0];
 			for (i = 0; i < cac_table->ucNumEntries; i++) {
 				if (rdev->pm.dpm.platform_caps & ATOM_PP_PLATFORM_CAP_EVV) {
 					rdev->pm.dpm.dyn_state.cac_leakage_table.entries[i].vddc1 =
-						le16_to_cpu(cac_table->entries[i].usVddc1);
+						le16_to_cpu(entry->usVddc1);
 					rdev->pm.dpm.dyn_state.cac_leakage_table.entries[i].vddc2 =
-						le16_to_cpu(cac_table->entries[i].usVddc2);
+						le16_to_cpu(entry->usVddc2);
 					rdev->pm.dpm.dyn_state.cac_leakage_table.entries[i].vddc3 =
-						le16_to_cpu(cac_table->entries[i].usVddc3);
+						le16_to_cpu(entry->usVddc3);
 				} else {
 					rdev->pm.dpm.dyn_state.cac_leakage_table.entries[i].vddc =
-						le16_to_cpu(cac_table->entries[i].usVddc);
+						le16_to_cpu(entry->usVddc);
 					rdev->pm.dpm.dyn_state.cac_leakage_table.entries[i].leakage =
-						le32_to_cpu(cac_table->entries[i].ulLeakageValue);
+						le32_to_cpu(entry->ulLeakageValue);
 				}
+				entry = (ATOM_PPLIB_CAC_Leakage_Record *)
+					((u8 *)entry + sizeof(ATOM_PPLIB_CAC_Leakage_Record));
 			}
 			rdev->pm.dpm.dyn_state.cac_leakage_table.count = cac_table->ucNumEntries;
 		}
@@ -1017,6 +1027,7 @@ int r600_parse_extended_power_table(struct radeon_device *rdev)
 				(mode_info->atom_context->bios + data_offset +
 				 le16_to_cpu(ext_hdr->usVCETableOffset) + 1 +
 				 1 + array->ucNumEntries * sizeof(VCEClockInfo));
+			ATOM_PPLIB_VCE_Clock_Voltage_Limit_Record *entry;
 			u32 size = limits->numEntries *
 				sizeof(struct radeon_vce_clock_voltage_dependency_entry);
 			rdev->pm.dpm.dyn_state.vce_clock_voltage_dependency_table.entries =
@@ -1027,15 +1038,19 @@ int r600_parse_extended_power_table(struct radeon_device *rdev)
 			}
 			rdev->pm.dpm.dyn_state.vce_clock_voltage_dependency_table.count =
 				limits->numEntries;
+			entry = &limits->entries[0];
 			for (i = 0; i < limits->numEntries; i++) {
-				VCEClockInfo *vce_clk =
-					&array->entries[limits->entries[i].ucVCEClockInfoIndex];
+				VCEClockInfo *vce_clk = (VCEClockInfo *)
+					((u8 *)&array->entries[0] +
+					 (entry->ucVCEClockInfoIndex * sizeof(VCEClockInfo)));
 				rdev->pm.dpm.dyn_state.vce_clock_voltage_dependency_table.entries[i].evclk =
 					le16_to_cpu(vce_clk->usEVClkLow) | (vce_clk->ucEVClkHigh << 16);
 				rdev->pm.dpm.dyn_state.vce_clock_voltage_dependency_table.entries[i].ecclk =
 					le16_to_cpu(vce_clk->usECClkLow) | (vce_clk->ucECClkHigh << 16);
 				rdev->pm.dpm.dyn_state.vce_clock_voltage_dependency_table.entries[i].v =
-					le16_to_cpu(limits->entries[i].usVoltage);
+					le16_to_cpu(entry->usVoltage);
+				entry = (ATOM_PPLIB_VCE_Clock_Voltage_Limit_Record *)
+					((u8 *)entry + sizeof(ATOM_PPLIB_VCE_Clock_Voltage_Limit_Record));
 			}
 		}
 		if ((le16_to_cpu(ext_hdr->usSize) >= SIZE_OF_ATOM_PPLIB_EXTENDEDHEADER_V3) &&
@@ -1048,6 +1063,7 @@ int r600_parse_extended_power_table(struct radeon_device *rdev)
 				(mode_info->atom_context->bios + data_offset +
 				 le16_to_cpu(ext_hdr->usUVDTableOffset) + 1 +
 				 1 + (array->ucNumEntries * sizeof (UVDClockInfo)));
+			ATOM_PPLIB_UVD_Clock_Voltage_Limit_Record *entry;
 			u32 size = limits->numEntries *
 				sizeof(struct radeon_uvd_clock_voltage_dependency_entry);
 			rdev->pm.dpm.dyn_state.uvd_clock_voltage_dependency_table.entries =
@@ -1058,15 +1074,19 @@ int r600_parse_extended_power_table(struct radeon_device *rdev)
 			}
 			rdev->pm.dpm.dyn_state.uvd_clock_voltage_dependency_table.count =
 				limits->numEntries;
+			entry = &limits->entries[0];
 			for (i = 0; i < limits->numEntries; i++) {
-				UVDClockInfo *uvd_clk =
-					&array->entries[limits->entries[i].ucUVDClockInfoIndex];
+				UVDClockInfo *uvd_clk = (UVDClockInfo *)
+					((u8 *)&array->entries[0] +
+					 (entry->ucUVDClockInfoIndex * sizeof(UVDClockInfo)));
 				rdev->pm.dpm.dyn_state.uvd_clock_voltage_dependency_table.entries[i].vclk =
 					le16_to_cpu(uvd_clk->usVClkLow) | (uvd_clk->ucVClkHigh << 16);
 				rdev->pm.dpm.dyn_state.uvd_clock_voltage_dependency_table.entries[i].dclk =
 					le16_to_cpu(uvd_clk->usDClkLow) | (uvd_clk->ucDClkHigh << 16);
 				rdev->pm.dpm.dyn_state.uvd_clock_voltage_dependency_table.entries[i].v =
 					le16_to_cpu(limits->entries[i].usVoltage);
+				entry = (ATOM_PPLIB_UVD_Clock_Voltage_Limit_Record *)
+					((u8 *)entry + sizeof(ATOM_PPLIB_UVD_Clock_Voltage_Limit_Record));
 			}
 		}
 		if ((le16_to_cpu(ext_hdr->usSize) >= SIZE_OF_ATOM_PPLIB_EXTENDEDHEADER_V4) &&
@@ -1075,6 +1095,7 @@ int r600_parse_extended_power_table(struct radeon_device *rdev)
 				(ATOM_PPLIB_SAMClk_Voltage_Limit_Table *)
 				(mode_info->atom_context->bios + data_offset +
 				 le16_to_cpu(ext_hdr->usSAMUTableOffset) + 1);
+			ATOM_PPLIB_SAMClk_Voltage_Limit_Record *entry;
 			u32 size = limits->numEntries *
 				sizeof(struct radeon_clock_voltage_dependency_entry);
 			rdev->pm.dpm.dyn_state.samu_clock_voltage_dependency_table.entries =
@@ -1085,12 +1106,14 @@ int r600_parse_extended_power_table(struct radeon_device *rdev)
 			}
 			rdev->pm.dpm.dyn_state.samu_clock_voltage_dependency_table.count =
 				limits->numEntries;
+			entry = &limits->entries[0];
 			for (i = 0; i < limits->numEntries; i++) {
 				rdev->pm.dpm.dyn_state.samu_clock_voltage_dependency_table.entries[i].clk =
-					le16_to_cpu(limits->entries[i].usSAMClockLow) |
-					(limits->entries[i].ucSAMClockHigh << 16);
+					le16_to_cpu(entry->usSAMClockLow) | (entry->ucSAMClockHigh << 16);
 				rdev->pm.dpm.dyn_state.samu_clock_voltage_dependency_table.entries[i].v =
-					le16_to_cpu(limits->entries[i].usVoltage);
+					le16_to_cpu(entry->usVoltage);
+				entry = (ATOM_PPLIB_SAMClk_Voltage_Limit_Record *)
+					((u8 *)entry + sizeof(ATOM_PPLIB_SAMClk_Voltage_Limit_Record));
 			}
 		}
 		if ((le16_to_cpu(ext_hdr->usSize) >= SIZE_OF_ATOM_PPLIB_EXTENDEDHEADER_V5) &&
@@ -1130,6 +1153,7 @@ int r600_parse_extended_power_table(struct radeon_device *rdev)
 				(ATOM_PPLIB_ACPClk_Voltage_Limit_Table *)
 				(mode_info->atom_context->bios + data_offset +
 				 le16_to_cpu(ext_hdr->usACPTableOffset) + 1);
+			ATOM_PPLIB_ACPClk_Voltage_Limit_Record *entry;
 			u32 size = limits->numEntries *
 				sizeof(struct radeon_clock_voltage_dependency_entry);
 			rdev->pm.dpm.dyn_state.acp_clock_voltage_dependency_table.entries =
@@ -1140,12 +1164,14 @@ int r600_parse_extended_power_table(struct radeon_device *rdev)
 			}
 			rdev->pm.dpm.dyn_state.acp_clock_voltage_dependency_table.count =
 				limits->numEntries;
+			entry = &limits->entries[0];
 			for (i = 0; i < limits->numEntries; i++) {
 				rdev->pm.dpm.dyn_state.acp_clock_voltage_dependency_table.entries[i].clk =
-					le16_to_cpu(limits->entries[i].usACPClockLow) |
-					(limits->entries[i].ucACPClockHigh << 16);
+					le16_to_cpu(entry->usACPClockLow) | (entry->ucACPClockHigh << 16);
 				rdev->pm.dpm.dyn_state.acp_clock_voltage_dependency_table.entries[i].v =
-					le16_to_cpu(limits->entries[i].usVoltage);
+					le16_to_cpu(entry->usVoltage);
+				entry = (ATOM_PPLIB_ACPClk_Voltage_Limit_Record *)
+					((u8 *)entry + sizeof(ATOM_PPLIB_ACPClk_Voltage_Limit_Record));
 			}
 		}
 		if ((le16_to_cpu(ext_hdr->usSize) >= SIZE_OF_ATOM_PPLIB_EXTENDEDHEADER_V7) &&