/* SPDX-License-Identifier: GPL-2.0-or-later */ /** * @file ddr3.c * * \brief Utilities for decoding DDR3 SPDs */ #include #include #include #include #include #include #include #include #include /*============================================================================== * = DDR3 SPD decoding helpers *----------------------------------------------------------------------------*/ /** * \brief Checks if the DIMM is Registered based on byte[3] of the SPD * * Tells if the DIMM type is registered or not. * * @param type DIMM type. This is byte[3] of the SPD. */ int spd_dimm_is_registered_ddr3(enum spd_dimm_type_ddr3 type) { if ((type == SPD_DDR3_DIMM_TYPE_RDIMM) | (type == SPD_DDR3_DIMM_TYPE_MINI_RDIMM) | (type == SPD_DDR3_DIMM_TYPE_72B_SO_RDIMM)) return 1; return 0; } /** * \brief Calculate the CRC of a DDR3 SPD * * @param spd pointer to raw SPD data * @param len length of data in SPD * * @return the CRC of the SPD data, or 0 when spd data is truncated. */ u16 spd_ddr3_calc_crc(u8 *spd, int len) { int n_crc; /* Find the number of bytes covered by CRC */ if (spd[0] & 0x80) { n_crc = 117; } else { n_crc = 126; } if (len < n_crc) /* Not enough bytes available to get the CRC */ return 0; return ddr_crc16(spd, n_crc); } /** * \brief Calculate the CRC of a DDR3 SPD unique identifier * * @param spd pointer to raw SPD data * @param len length of data in SPD * * @return the CRC of SPD data bytes 117..127, or 0 when spd data is truncated. */ u16 spd_ddr3_calc_unique_crc(u8 *spd, int len) { if (len < (117 + 11)) /* Not enough bytes available to get the CRC */ return 0; return ddr_crc16(&spd[117], 11); } /** * \brief Decode the raw SPD data * * Decodes a raw SPD data from a DDR3 DIMM, and organizes it into a * @ref dimm_attr structure. The SPD data must first be read in a contiguous * array, and passed to this function. * * @param dimm pointer to @ref dimm_attr structure where the decoded data is to * be stored * @param spd array of raw data previously read from the SPD. * * @return @ref spd_status enumerator * SPD_STATUS_OK -- decoding was successful * SPD_STATUS_INVALID -- invalid SPD or not a DDR3 SPD * SPD_STATUS_CRC_ERROR -- CRC did not verify * SPD_STATUS_INVALID_FIELD -- A field with an invalid value was * detected. */ int spd_decode_ddr3(struct dimm_attr_ddr3_st *dimm, spd_ddr3_raw_data spd) { int ret; u16 crc, spd_crc; u8 capacity_shift, bus_width; u8 reg8; u32 mtb; /* medium time base */ u32 ftb; /* fine time base */ unsigned int val; ret = SPD_STATUS_OK; /* Don't assume we memset 0 dimm struct. Clear all our flags */ dimm->flags.raw = 0; dimm->dimms_per_channel = 3; /* Make sure that the SPD dump is indeed from a DDR3 module */ if (spd[2] != SPD_MEMORY_TYPE_SDRAM_DDR3) { printram("Not a DDR3 SPD!\n"); dimm->dram_type = SPD_MEMORY_TYPE_UNDEFINED; return SPD_STATUS_INVALID; } dimm->dram_type = SPD_MEMORY_TYPE_SDRAM_DDR3; dimm->dimm_type = spd[3] & 0xf; crc = spd_ddr3_calc_crc(spd, sizeof(spd_ddr3_raw_data)); /* Compare with the CRC in the SPD */ spd_crc = (spd[127] << 8) + spd[126]; /* Verify the CRC is correct */ if (crc != spd_crc) { printram("ERROR: SPD CRC failed!!!\n"); ret = SPD_STATUS_CRC_ERROR; }; printram(" Revision : %x\n", spd[1]); printram(" Type : %x\n", spd[2]); printram(" Key : %x\n", spd[3]); reg8 = spd[4]; /* Number of memory banks */ val = (reg8 >> 4) & 0x07; if (val > 0x03) { printram(" Invalid number of memory banks\n"); ret = SPD_STATUS_INVALID_FIELD; } printram(" Banks : %u\n", 1 << (val + 3)); /* SDRAM capacity */ capacity_shift = reg8 & 0x0f; if (capacity_shift > 0x06) { printram(" Invalid module capacity\n"); ret = SPD_STATUS_INVALID_FIELD; } if (capacity_shift < 0x02) { printram(" Capacity : %u Mb\n", 256 << capacity_shift); } else { printram(" Capacity : %u Gb\n", 1 << (capacity_shift - 2)); } reg8 = spd[5]; /* Row address bits */ val = (reg8 >> 3) & 0x07; if (val > 0x04) { printram(" Invalid row address bits\n"); ret = SPD_STATUS_INVALID_FIELD; } dimm->row_bits = val + 12; /* Column address bits */ val = reg8 & 0x07; if (val > 0x03) { printram(" Invalid column address bits\n"); ret = SPD_STATUS_INVALID_FIELD; } dimm->col_bits = val + 9; /* Module nominal voltage */ reg8 = spd[6]; printram(" Supported voltages :"); if (reg8 & (1 << 2)) { dimm->flags.operable_1_25V = 1; dimm->voltage = 1250; printram(" 1.25V"); } if (reg8 & (1 << 1)) { dimm->flags.operable_1_35V = 1; dimm->voltage = 1300; printram(" 1.35V"); } if (!(reg8 & (1 << 0))) { dimm->flags.operable_1_50V = 1; dimm->voltage = 1500; printram(" 1.5V"); } printram("\n"); /* Module organization */ reg8 = spd[7]; /* Number of ranks */ val = (reg8 >> 3) & 0x07; if (val > 3) { printram(" Invalid number of ranks\n"); ret = SPD_STATUS_INVALID_FIELD; } dimm->ranks = val + 1; /* SDRAM device width */ val = (reg8 & 0x07); if (val > 3) { printram(" Invalid SDRAM width\n"); ret = SPD_STATUS_INVALID_FIELD; } dimm->width = (4 << val); printram(" SDRAM width : %u\n", dimm->width); /* Memory bus width */ reg8 = spd[8]; /* Bus extension */ val = (reg8 >> 3) & 0x03; if (val > 1) { printram(" Invalid bus extension\n"); ret = SPD_STATUS_INVALID_FIELD; } dimm->flags.is_ecc = val ? 1 : 0; printram(" Bus extension : %u bits\n", val ? 8 : 0); /* Bus width */ val = reg8 & 0x07; if (val > 3) { printram(" Invalid bus width\n"); ret = SPD_STATUS_INVALID_FIELD; } bus_width = 8 << val; printram(" Bus width : %u\n", bus_width); /* We have all the info we need to compute the dimm size */ /* Capacity is 256Mbit multiplied by the power of 2 specified in * capacity_shift * The rest is the JEDEC formula */ dimm->size_mb = ((1 << (capacity_shift + (25 - 20))) * bus_width * dimm->ranks) / dimm->width; /* Medium Timebase = * Medium Timebase (MTB) Dividend / * Medium Timebase (MTB) Divisor */ mtb = (((u32)spd[10]) << 8) / spd[11]; /* SDRAM Minimum Cycle Time (tCKmin) */ dimm->tCK = spd[12] * mtb; /* CAS Latencies Supported */ dimm->cas_supported = (spd[15] << 8) + spd[14]; /* Minimum CAS Latency Time (tAAmin) */ dimm->tAA = spd[16] * mtb; /* Minimum Write Recovery Time (tWRmin) */ dimm->tWR = spd[17] * mtb; /* Minimum RAS# to CAS# Delay Time (tRCDmin) */ dimm->tRCD = spd[18] * mtb; /* Minimum Row Active to Row Active Delay Time (tRRDmin) */ dimm->tRRD = spd[19] * mtb; /* Minimum Row Precharge Delay Time (tRPmin) */ dimm->tRP = spd[20] * mtb; /* Minimum Active to Precharge Delay Time (tRASmin) */ dimm->tRAS = (((spd[21] & 0x0f) << 8) + spd[22]) * mtb; /* Minimum Active to Active/Refresh Delay Time (tRCmin) */ dimm->tRC = (((spd[21] & 0xf0) << 4) + spd[23]) * mtb; /* Minimum Refresh Recovery Delay Time (tRFCmin) */ dimm->tRFC = ((spd[25] << 8) + spd[24]) * mtb; /* Minimum Internal Write to Read Command Delay Time (tWTRmin) */ dimm->tWTR = spd[26] * mtb; /* Minimum Internal Read to Precharge Command Delay Time (tRTPmin) */ dimm->tRTP = spd[27] * mtb; /* Minimum Four Activate Window Delay Time (tFAWmin) */ dimm->tFAW = (((spd[28] & 0x0f) << 8) + spd[29]) * mtb; /* Minimum CAS Write Latency Time (tCWLmin) * - not present in standard SPD */ dimm->tCWL = 0; /* System CMD Rate Mode - not present in standard SPD */ dimm->tCMD = 0; printram(" FTB timings :"); /* FTB is introduced in SPD revision 1.1 */ if (spd[1] >= 0x11 && spd[9] & 0x0f) { printram(" yes\n"); /* Fine timebase (1/256 ps) = * Fine Timebase (FTB) Dividend / * Fine Timebase (FTB) Divisor */ ftb = (((u16)spd[9] & 0xf0) << 4) / (spd[9] & 0x0f); /* SPD recommends to round up the MTB part and use a negative * FTB, so a negative rounding should be always safe */ /* SDRAM Minimum Cycle Time (tCKmin) correction */ dimm->tCK += (s32)((s8)spd[34] * ftb - 500) / 1000; /* Minimum CAS Latency Time (tAAmin) correction */ dimm->tAA += (s32)((s8)spd[35] * ftb - 500) / 1000; /* Minimum RAS# to CAS# Delay Time (tRCDmin) correction */ dimm->tRCD += (s32)((s8)spd[36] * ftb - 500) / 1000; /* Minimum Row Precharge Delay Time (tRPmin) correction */ dimm->tRP += (s32)((s8)spd[37] * ftb - 500) / 1000; /* Minimum Active to Active/Refresh Delay Time (tRCmin) corr. */ dimm->tRC += (s32)((s8)spd[38] * ftb - 500) / 1000; } else { printram(" no\n"); } /* SDRAM Optional Features */ reg8 = spd[30]; printram(" Optional features :"); if (reg8 & 0x80) { dimm->flags.dll_off_mode = 1; printram(" DLL-Off_mode"); } if (reg8 & 0x02) { dimm->flags.rzq7_supported = 1; printram(" RZQ/7"); } if (reg8 & 0x01) { dimm->flags.rzq6_supported = 1; printram(" RZQ/6"); } printram("\n"); /* SDRAM Thermal and Refresh Options */ reg8 = spd[31]; printram(" Thermal features :"); if (reg8 & 0x80) { dimm->flags.pasr = 1; printram(" PASR"); } if (reg8 & 0x08) { dimm->flags.odts = 1; printram(" ODTS"); } if (reg8 & 0x04) { dimm->flags.asr = 1; printram(" ASR"); } if (reg8 & 0x02) { dimm->flags.ext_temp_range = 1; printram(" ext_temp_refresh"); } if (reg8 & 0x01) { dimm->flags.ext_temp_refresh = 1; printram(" ext_temp_range"); } printram("\n"); /* Module Thermal Sensor */ reg8 = spd[32]; if (reg8 & 0x80) dimm->flags.therm_sensor = 1; printram(" Thermal sensor : %s\n", dimm->flags.therm_sensor ? "yes" : "no"); /* SDRAM Device Type */ printram(" Standard SDRAM : %s\n", (spd[33] & 0x80) ? "no" : "yes"); if (spd[63] & 0x01) { dimm->flags.pins_mirrored = 1; } printram(" Rank1 Address bits : %s\n", (spd[63] & 0x01) ? "mirrored" : "normal"); dimm->reference_card = spd[62] & 0x1f; printram(" DIMM Reference card: %c\n", 'A' + dimm->reference_card); dimm->manufacturer_id = (spd[118] << 8) | spd[117]; printram(" Manufacturer ID : %x\n", dimm->manufacturer_id); dimm->part_number[16] = 0; memcpy(dimm->part_number, &spd[128], 16); printram(" Part number : %s\n", dimm->part_number); memcpy(dimm->serial, &spd[SPD_DDR3_SERIAL_NUM], SPD_DDR3_SERIAL_LEN); return ret; } /** * \brief Decode the raw SPD XMP data * * Decodes a raw SPD XMP data from a DDR3 DIMM, and organizes it into a * @ref dimm_attr structure. The SPD data must first be read in a contiguous * array, and passed to this function. * * @param dimm pointer to @ref dimm_attr structure where the decoded data is to * be stored * @param spd array of raw data previously read from the SPD. * * @param profile select one of the profiles to load * * @return @ref spd_status enumerator * SPD_STATUS_OK -- decoding was successful * SPD_STATUS_INVALID -- invalid SPD or not a DDR3 SPD * SPD_STATUS_CRC_ERROR -- CRC did not verify * SPD_STATUS_INVALID_FIELD -- A field with an invalid value was * detected. */ int spd_xmp_decode_ddr3(struct dimm_attr_ddr3_st *dimm, spd_ddr3_raw_data spd, enum ddr3_xmp_profile profile) { int ret; u32 mtb; /* medium time base */ u8 *xmp; /* pointer to XMP profile data */ /* need a valid SPD */ ret = spd_decode_ddr3(dimm, spd); if (ret != SPD_STATUS_OK) return ret; /* search for magic header */ if (spd[176] != 0x0C || spd[177] != 0x4A) { printram("Not a DDR3 XMP profile!\n"); dimm->dram_type = SPD_MEMORY_TYPE_UNDEFINED; return SPD_STATUS_INVALID; } if (profile == DDR3_XMP_PROFILE_1) { if (!(spd[178] & 1)) { printram("Selected XMP profile disabled!\n"); dimm->dram_type = SPD_MEMORY_TYPE_UNDEFINED; return SPD_STATUS_INVALID; } printram(" XMP Profile : 1\n"); xmp = &spd[185]; /* Medium Timebase = * Medium Timebase (MTB) Dividend / * Medium Timebase (MTB) Divisor */ if (spd[181] == 0) // Avoid dividing by zero. return SPD_STATUS_INVALID; mtb = (((u32)spd[180]) << 8) / spd[181]; dimm->dimms_per_channel = ((spd[178] >> 2) & 0x3) + 1; } else { if (!(spd[178] & 2)) { printram("Selected XMP profile disabled!\n"); dimm->dram_type = SPD_MEMORY_TYPE_UNDEFINED; return SPD_STATUS_INVALID; } printram(" XMP Profile : 2\n"); xmp = &spd[220]; /* Medium Timebase = * Medium Timebase (MTB) Dividend / * Medium Timebase (MTB) Divisor */ if (spd[183] == 0) // Avoid dividing by zero. return SPD_STATUS_INVALID; mtb = (((u32)spd[182]) << 8) / spd[183]; dimm->dimms_per_channel = ((spd[178] >> 4) & 0x3) + 1; } printram(" Max DIMMs/channel : %u\n", dimm->dimms_per_channel); printram(" XMP Revision : %u.%u\n", spd[179] >> 4, spd[179] & 0xf); /* calculate voltage in mV */ dimm->voltage = (xmp[0] & 1) * 50; dimm->voltage += ((xmp[0] >> 1) & 0xf) * 100; dimm->voltage += ((xmp[0] >> 5) & 0x3) * 1000; printram(" Requested voltage : %u mV\n", dimm->voltage); /* SDRAM Minimum Cycle Time (tCKmin) */ dimm->tCK = xmp[1] * mtb; /* CAS Latencies Supported */ dimm->cas_supported = ((xmp[4] << 8) + xmp[3]) & 0x7fff; /* Minimum CAS Latency Time (tAAmin) */ dimm->tAA = xmp[2] * mtb; /* Minimum Write Recovery Time (tWRmin) */ dimm->tWR = xmp[8] * mtb; /* Minimum RAS# to CAS# Delay Time (tRCDmin) */ dimm->tRCD = xmp[7] * mtb; /* Minimum Row Active to Row Active Delay Time (tRRDmin) */ dimm->tRRD = xmp[17] * mtb; /* Minimum Row Precharge Delay Time (tRPmin) */ dimm->tRP = xmp[6] * mtb; /* Minimum Active to Precharge Delay Time (tRASmin) */ dimm->tRAS = (((xmp[9] & 0x0f) << 8) + xmp[10]) * mtb; /* Minimum Active to Active/Refresh Delay Time (tRCmin) */ dimm->tRC = (((xmp[9] & 0xf0) << 4) + xmp[11]) * mtb; /* Minimum Refresh Recovery Delay Time (tRFCmin) */ dimm->tRFC = ((xmp[15] << 8) + xmp[14]) * mtb; /* Minimum Internal Write to Read Command Delay Time (tWTRmin) */ dimm->tWTR = xmp[20] * mtb; /* Minimum Internal Read to Precharge Command Delay Time (tRTPmin) */ dimm->tRTP = xmp[16] * mtb; /* Minimum Four Activate Window Delay Time (tFAWmin) */ dimm->tFAW = (((xmp[18] & 0x0f) << 8) + xmp[19]) * mtb; /* Minimum CAS Write Latency Time (tCWLmin) */ dimm->tCWL = xmp[5] * mtb; /* System CMD Rate Mode */ dimm->tCMD = xmp[23] * mtb; return ret; } /** * Fill cbmem with information for SMBIOS type 17. * * @param channel Corresponding channel of provided @info * @param slot Corresponding slot of provided @info * @param selected_freq The actual frequency the DRAM is running on * @param info DIMM parameters read from SPD * * @return CB_SUCCESS if DIMM info was written */ enum cb_err spd_add_smbios17(const u8 channel, const u8 slot, const u16 selected_freq, const struct dimm_attr_ddr3_st *info) { struct memory_info *mem_info; struct dimm_info *dimm; /* * Allocate CBMEM area for DIMM information used to populate SMBIOS * table 17 */ mem_info = cbmem_find(CBMEM_ID_MEMINFO); if (!mem_info) { mem_info = cbmem_add(CBMEM_ID_MEMINFO, sizeof(*mem_info)); printk(BIOS_DEBUG, "CBMEM entry for DIMM info: %p\n", mem_info); if (!mem_info) return CB_ERR; memset(mem_info, 0, sizeof(*mem_info)); } if (mem_info->dimm_cnt >= ARRAY_SIZE(mem_info->dimm)) { printk(BIOS_WARNING, "BUG: Too many DIMM infos for %s.\n", __func__); return CB_ERR; } dimm = &mem_info->dimm[mem_info->dimm_cnt]; if (info->size_mb) { dimm->ddr_type = MEMORY_TYPE_DDR3; dimm->ddr_frequency = selected_freq; dimm->dimm_size = info->size_mb; dimm->channel_num = channel; dimm->rank_per_dimm = info->ranks; dimm->dimm_num = slot; memcpy(dimm->module_part_number, info->part_number, 16); dimm->mod_id = info->manufacturer_id; dimm->mod_type = info->dimm_type; dimm->bus_width = MEMORY_BUS_WIDTH_64; // non-ECC only memcpy(dimm->serial, info->serial, MIN(sizeof(dimm->serial), sizeof(info->serial))); mem_info->dimm_cnt++; } return CB_SUCCESS; } /* * The information printed below has a more informational character, and is not * necessarily tied in to RAM init debugging. Hence, we stop using printram(), * and use the standard printk()'s below. */ static void print_ns(const char *msg, u32 val) { u32 mant, fp; mant = val / 256; fp = (val % 256) * 1000 / 256; printk(BIOS_INFO, "%s%3u.%.3u ns\n", msg, mant, fp); } /** * \brief Print the info in DIMM * * Print info about the DIMM. Useful to use when CONFIG(DEBUG_RAM_SETUP) is * selected, or for a purely informative output. * * @param dimm pointer to already decoded @ref dimm_attr structure */ void dram_print_spd_ddr3(const struct dimm_attr_ddr3_st *dimm) { u16 val16; int i; printk(BIOS_INFO, " Row addr bits : %u\n", dimm->row_bits); printk(BIOS_INFO, " Column addr bits : %u\n", dimm->col_bits); printk(BIOS_INFO, " Number of ranks : %u\n", dimm->ranks); printk(BIOS_INFO, " DIMM Capacity : %u MB\n", dimm->size_mb); /* CAS Latencies Supported */ val16 = dimm->cas_supported; printk(BIOS_INFO, " CAS latencies :"); i = 0; do { if (val16 & 1) printk(BIOS_INFO, " %u", i + 4); i++; val16 >>= 1; } while (val16); printk(BIOS_INFO, "\n"); print_ns(" tCKmin : ", dimm->tCK); print_ns(" tAAmin : ", dimm->tAA); print_ns(" tWRmin : ", dimm->tWR); print_ns(" tRCDmin : ", dimm->tRCD); print_ns(" tRRDmin : ", dimm->tRRD); print_ns(" tRPmin : ", dimm->tRP); print_ns(" tRASmin : ", dimm->tRAS); print_ns(" tRCmin : ", dimm->tRC); print_ns(" tRFCmin : ", dimm->tRFC); print_ns(" tWTRmin : ", dimm->tWTR); print_ns(" tRTPmin : ", dimm->tRTP); print_ns(" tFAWmin : ", dimm->tFAW); /* Those values are only relevant if an XMP profile sets them */ if (dimm->tCWL) print_ns(" tCWLmin : ", dimm->tCWL); if (dimm->tCMD) printk(BIOS_INFO, " tCMDmin : %3u\n", DIV_ROUND_UP(dimm->tCMD, 256)); }