northbridge/amd/amdfam10: Set DIMM voltage based on SPD data

Change-Id: I67a76cf0e4ebc33fbd7dd151bb68dce1fc6ba680
Signed-off-by: Timothy Pearson <tpearson@raptorengineeringinc.com>
Reviewed-on: http://review.coreboot.org/11957
Tested-by: build bot (Jenkins)
Reviewed-by: Felix Held <felix-coreboot@felixheld.de>

src/northbridge/amd/amdfam10/Kconfig

@@ -83,6 +83,10 @@ config DIMM_REGISTERED
 	bool
 	default n
 
+config DIMM_VOLTAGE_SET_SUPPORT
+	bool
+	default n
+
 if DIMM_FBDIMM
 	config DIMM_SUPPORT
 		hex

src/northbridge/amd/amdfam10/acpi.c

@@ -303,8 +303,7 @@ void northbridge_acpi_write_vars(device_t device)
 	} else {
 		if((sysconf.pci1234[0] >> 12) & 0xff) { //sb chain on  other than bus 0
 			CBST = (u8) (0x0f);
-		}
+		} else {
-		else {
 			CBST = (u8) (0x00);
 		}
 	}

src/northbridge/amd/amdfam10/northbridge.c

@@ -1063,6 +1063,36 @@ static int amdfam10_get_smbios_data17(int* count, int handle, int parent_handle,
 					snprintf(string_buffer, sizeof (string_buffer), "%08X", mem_info->dct_stat[node].DimmSerialNumber[slot]);
 					t->serial_number = smbios_add_string(t->eos, string_buffer);
 				}
+				if (IS_ENABLED(CONFIG_DIMM_DDR2)) {
+					/* JEDEC specifies 1.8V only, so assume that the memory is configured for 1.8V */
+					t->minimum_voltage = 1800;
+					t->maximum_voltage = 1800;
+					t->configured_voltage = 1800;
+				} else if (IS_ENABLED(CONFIG_DIMM_DDR3)) {
+#if IS_ENABLED(CONFIG_DIMM_DDR3)
+					/* Find the maximum and minimum supported voltages */
+					uint8_t supported_voltages = mem_info->dct_stat[node].DimmSupportedVoltages[slot];
+					if (supported_voltages & 0x8)
+						t->minimum_voltage = 1150;
+					else if (supported_voltages & 0x4)
+						t->minimum_voltage = 1250;
+					else if (supported_voltages & 0x2)
+						t->minimum_voltage = 1350;
+					else if (supported_voltages & 0x1)
+						t->minimum_voltage = 1500;
+
+					if (supported_voltages & 0x1)
+						t->maximum_voltage = 1500;
+					else if (supported_voltages & 0x2)
+						t->maximum_voltage = 1350;
+					else if (supported_voltages & 0x4)
+						t->maximum_voltage = 1250;
+					else if (supported_voltages & 0x8)
+						t->maximum_voltage = 1150;
+
+					t->configured_voltage = mem_info->dct_stat[node].DimmConfiguredVoltage[slot];
+#endif
+				}
 				t->memory_error_information_handle = 0xFFFE;	/* no error information handle available */
 				single_len = t->length + smbios_string_table_len(t->eos);
 				len += single_len;

src/northbridge/amd/amdmct/mct_ddr3/mct_d.c

@@ -336,6 +336,11 @@ restartinit:
 			goto fatalexit;
 		}
 
+#if IS_ENABLED(DIMM_VOLTAGE_SET_SUPPORT)
+		printk(BIOS_DEBUG, "mctAutoInitMCT_D: DIMMSetVoltage\n");
+		DIMMSetVoltages(pMCTstat, pDCTstatA);	/* Set the DIMM voltages (mainboard specific) */
+#endif
+
 		printk(BIOS_DEBUG, "mctAutoInitMCT_D: SyncDCTsReady_D\n");
 		SyncDCTsReady_D(pMCTstat, pDCTstatA);	/* Make sure DCTs are ready for accesses.*/
 
@@ -2128,6 +2133,9 @@ static u8 DIMMPresence_D(struct MCTStatStruc *pMCTstat,
 					pDCTstat->DimmBanks[i] = 1ULL << (((mctRead_SPD(smbaddr, SPD_Density) & 0x70) >> 4) + 3);
 					pDCTstat->DimmWidth[i] = 1ULL << ((mctRead_SPD(smbaddr, SPD_BusWidth) & 0x7) + 3);
 				}
+				/* Check supported voltage(s) */
+				pDCTstat->DimmSupportedVoltages[i] = mctRead_SPD(smbaddr, SPD_Voltage) & 0x7;
+				pDCTstat->DimmSupportedVoltages[i] ^= 0x1;	/* Invert LSB to convert from SPD format to internal bitmap format */
 				/* Check module type */
 				byte = mctRead_SPD(smbaddr, SPD_DIMMTYPE) & 0x7;
 				if (byte == JED_RDIMM || byte == JED_MiniRDIMM) {

src/northbridge/amd/amdmct/mct_ddr3/mct_d.h

@@ -202,6 +202,7 @@
 	#define JED_MiniRDIMM	0x5	/* Mini-RDIMM */
 #define SPD_Density	4		/* Bank address bits,SDRAM capacity */
 #define SPD_Addressing	5		/* Row/Column address bits */
+#define SPD_Voltage	6		/* Supported voltage bitfield */
 #define SPD_Organization	7		/* rank#,Device width */
 #define SPD_BusWidth	8		/* ECC, Bus width */
 	#define JED_ECC		8	/* ECC capability */
@@ -581,6 +582,10 @@ struct DCTStatStruc {		/* A per Node structure*/
 	struct _sDCTStruct s_C_DCTPtr[2];
 	/* struct _sDCTStruct s_C_DCT1Ptr[8]; */
 
+	/* DIMM supported voltage bitmap ([2:0]: 1.25V, 1.35V, 1.5V) */
+	uint8_t DimmSupportedVoltages[MAX_DIMMS_SUPPORTED];
+	uint32_t DimmConfiguredVoltage[MAX_DIMMS_SUPPORTED];	/* mV */
+
 	uint8_t DimmRows[MAX_DIMMS_SUPPORTED];
 	uint8_t DimmCols[MAX_DIMMS_SUPPORTED];
 	uint8_t DimmRanks[MAX_DIMMS_SUPPORTED];
@@ -901,6 +906,7 @@ u32 procOdtWorkaround(struct DCTStatStruc *pDCTstat, u32 dct, u32 val);
 void mct_BeforeDramInit_D(struct DCTStatStruc *pDCTstat, u32 dct);
 void mctGet_DIMMAddr(struct DCTStatStruc *pDCTstat, u32 node);
 void mctSMBhub_Init(u32 node);
+void DIMMSetVoltages(struct MCTStatStruc *pMCTstat, struct DCTStatStruc *pDCTstatA);
 int mctRead_SPD(u32 smaddr, u32 reg);
 void InterleaveNodes_D(struct MCTStatStruc *pMCTstat, struct DCTStatStruc *pDCTstatA);
 void InterleaveChannels_D(struct MCTStatStruc *pMCTstat, struct DCTStatStruc *pDCTstatA);