// SPDX-License-Identifier: GPL-2.0+ /* * Copyright 2014-2016 Freescale Semiconductor, Inc. * Copyright 2017-2018 NXP Semiconductor * * calculate the organization and timing parameter * from ddr3 spd, please refer to the spec * JEDEC standard No.21-C 4_01_02_12R23A.pdf * * */ #include #include #include #include /* * Calculate the Density of each Physical Rank. * Returned size is in bytes. * * Total DIMM size = * sdram capacity(bit) / 8 * primary bus width / sdram width * * Logical Ranks per DIMM * * where: sdram capacity = spd byte4[3:0] * primary bus width = spd byte13[2:0] * sdram width = spd byte12[2:0] * Logical Ranks per DIMM = spd byte12[5:3] for SDP, DDP, QDP * spd byte12{5:3] * spd byte6[6:4] for 3DS * * To simplify each rank size = total DIMM size / Number of Package Ranks * where Number of Package Ranks = spd byte12[5:3] * * SPD byte4 - sdram density and banks * bit[3:0] size(bit) size(byte) * 0000 256Mb 32MB * 0001 512Mb 64MB * 0010 1Gb 128MB * 0011 2Gb 256MB * 0100 4Gb 512MB * 0101 8Gb 1GB * 0110 16Gb 2GB * 0111 32Gb 4GB * * SPD byte13 - module memory bus width * bit[2:0] primary bus width * 000 8bits * 001 16bits * 010 32bits * 011 64bits * * SPD byte12 - module organization * bit[2:0] sdram device width * 000 4bits * 001 8bits * 010 16bits * 011 32bits * * SPD byte12 - module organization * bit[5:3] number of package ranks per DIMM * 000 1 * 001 2 * 010 3 * 011 4 * * SPD byte6 - SDRAM package type * bit[6:4] Die count * 000 1 * 001 2 * 010 3 * 011 4 * 100 5 * 101 6 * 110 7 * 111 8 * * SPD byte6 - SRAM package type * bit[1:0] Signal loading * 00 Not specified * 01 Multi load stack * 10 Sigle load stack (3DS) * 11 Reserved */ static unsigned long long compute_ranksize(const struct ddr4_spd_eeprom_s *spd) { unsigned long long bsize; int nbit_sdram_cap_bsize = 0; int nbit_primary_bus_width = 0; int nbit_sdram_width = 0; int die_count = 0; bool package_3ds; if ((spd->density_banks & 0xf) <= 7) nbit_sdram_cap_bsize = (spd->density_banks & 0xf) + 28; if ((spd->bus_width & 0x7) < 4) nbit_primary_bus_width = (spd->bus_width & 0x7) + 3; if ((spd->organization & 0x7) < 4) nbit_sdram_width = (spd->organization & 0x7) + 2; package_3ds = (spd->package_type & 0x3) == 0x2; if ((spd->package_type & 0x80) && !package_3ds) { /* other than 3DS */ printf("Warning: not supported SDRAM package type\n"); return 0; } if (package_3ds) die_count = (spd->package_type >> 4) & 0x7; bsize = 1ULL << (nbit_sdram_cap_bsize - 3 + nbit_primary_bus_width - nbit_sdram_width + die_count); debug("DDR: DDR rank density = 0x%16llx\n", bsize); return bsize; } #define spd_to_ps(mtb, ftb) \ (mtb * pdimm->mtb_ps + (ftb * pdimm->ftb_10th_ps) / 10) /* * ddr_compute_dimm_parameters for DDR4 SPD * * Compute DIMM parameters based upon the SPD information in spd. * Writes the results to the dimm_params_t structure pointed by pdimm. * */ unsigned int ddr_compute_dimm_parameters(const unsigned int ctrl_num, const generic_spd_eeprom_t *spd, dimm_params_t *pdimm, unsigned int dimm_number) { unsigned int retval; int i; const u8 udimm_rc_e_dq[18] = { 0x0c, 0x2c, 0x15, 0x35, 0x15, 0x35, 0x0b, 0x2c, 0x15, 0x35, 0x0b, 0x35, 0x0b, 0x2c, 0x0b, 0x35, 0x15, 0x36 }; int spd_error = 0; u8 *ptr; u8 val; if (spd->mem_type) { if (spd->mem_type != SPD_MEMTYPE_DDR4) { printf("Ctrl %u DIMM %u: is not a DDR4 SPD.\n", ctrl_num, dimm_number); return 1; } } else { memset(pdimm, 0, sizeof(dimm_params_t)); return 1; } retval = ddr4_spd_check(spd); if (retval) { printf("DIMM %u: failed checksum\n", dimm_number); return 2; } /* * The part name in ASCII in the SPD EEPROM is not null terminated. * Guarantee null termination here by presetting all bytes to 0 * and copying the part name in ASCII from the SPD onto it */ memset(pdimm->mpart, 0, sizeof(pdimm->mpart)); if ((spd->info_size_crc & 0xF) > 2) memcpy(pdimm->mpart, spd->mpart, sizeof(pdimm->mpart) - 1); /* DIMM organization parameters */ pdimm->n_ranks = ((spd->organization >> 3) & 0x7) + 1; pdimm->rank_density = compute_ranksize(spd); pdimm->capacity = pdimm->n_ranks * pdimm->rank_density; pdimm->die_density = spd->density_banks & 0xf; pdimm->primary_sdram_width = 1 << (3 + (spd->bus_width & 0x7)); if ((spd->bus_width >> 3) & 0x3) pdimm->ec_sdram_width = 8; else pdimm->ec_sdram_width = 0; pdimm->data_width = pdimm->primary_sdram_width + pdimm->ec_sdram_width; pdimm->device_width = 1 << ((spd->organization & 0x7) + 2); pdimm->package_3ds = (spd->package_type & 0x3) == 0x2 ? (spd->package_type >> 4) & 0x7 : 0; /* These are the types defined by the JEDEC SPD spec */ pdimm->mirrored_dimm = 0; pdimm->registered_dimm = 0; switch (spd->module_type & DDR4_SPD_MODULETYPE_MASK) { case DDR4_SPD_MODULETYPE_RDIMM: /* Registered/buffered DIMMs */ pdimm->registered_dimm = 1; if (spd->mod_section.registered.reg_map & 0x1) pdimm->mirrored_dimm = 1; val = spd->mod_section.registered.ca_stren; pdimm->rcw[3] = val >> 4; pdimm->rcw[4] = ((val & 0x3) << 2) | ((val & 0xc) >> 2); val = spd->mod_section.registered.clk_stren; pdimm->rcw[5] = ((val & 0x3) << 2) | ((val & 0xc) >> 2); /* Not all in SPD. For convience only. Boards may overwrite. */ pdimm->rcw[6] = 0xf; /* * A17 only used for 16Gb and above devices. * C[2:0] only used for 3DS. */ pdimm->rcw[8] = pdimm->die_density >= 0x6 ? 0x0 : 0x8 | (pdimm->package_3ds > 0x3 ? 0x0 : (pdimm->package_3ds > 0x1 ? 0x1 : (pdimm->package_3ds > 0 ? 0x2 : 0x3))); if (pdimm->package_3ds || pdimm->n_ranks != 4) pdimm->rcw[13] = 0xc; else pdimm->rcw[13] = 0xd; /* Fix encoded by board */ break; case DDR4_SPD_MODULETYPE_UDIMM: case DDR4_SPD_MODULETYPE_SO_DIMM: /* Unbuffered DIMMs */ if (spd->mod_section.unbuffered.addr_mapping & 0x1) pdimm->mirrored_dimm = 1; if ((spd->mod_section.unbuffered.mod_height & 0xe0) == 0 && (spd->mod_section.unbuffered.ref_raw_card == 0x04)) { /* Fix SPD error found on DIMMs with raw card E0 */ for (i = 0; i < 18; i++) { if (spd->mapping[i] == udimm_rc_e_dq[i]) continue; spd_error = 1; debug("SPD byte %d: 0x%x, should be 0x%x\n", 60 + i, spd->mapping[i], udimm_rc_e_dq[i]); ptr = (u8 *)&spd->mapping[i]; *ptr = udimm_rc_e_dq[i]; } if (spd_error) puts("SPD DQ mapping error fixed\n"); } break; default: printf("unknown module_type 0x%02X\n", spd->module_type); return 1; } /* SDRAM device parameters */ pdimm->n_row_addr = ((spd->addressing >> 3) & 0x7) + 12; pdimm->n_col_addr = (spd->addressing & 0x7) + 9; pdimm->bank_addr_bits = (spd->density_banks >> 4) & 0x3; pdimm->bank_group_bits = (spd->density_banks >> 6) & 0x3; /* * The SPD spec has not the ECC bit, * We consider the DIMM as ECC capability * when the extension bus exist */ if (pdimm->ec_sdram_width) pdimm->edc_config = 0x02; else pdimm->edc_config = 0x00; /* * The SPD spec has not the burst length byte * but DDR4 spec has nature BL8 and BC4, * BL8 -bit3, BC4 -bit2 */ pdimm->burst_lengths_bitmask = 0x0c; /* MTB - medium timebase * The MTB in the SPD spec is 125ps, * * FTB - fine timebase * use 1/10th of ps as our unit to avoid floating point * eg, 10 for 1ps, 25 for 2.5ps, 50 for 5ps */ if ((spd->timebases & 0xf) == 0x0) { pdimm->mtb_ps = 125; pdimm->ftb_10th_ps = 10; } else { printf("Unknown Timebases\n"); } /* sdram minimum cycle time */ pdimm->tckmin_x_ps = spd_to_ps(spd->tck_min, spd->fine_tck_min); /* sdram max cycle time */ pdimm->tckmax_ps = spd_to_ps(spd->tck_max, spd->fine_tck_max); /* * CAS latency supported * bit0 - CL7 * bit4 - CL11 * bit8 - CL15 * bit12- CL19 * bit16- CL23 */ pdimm->caslat_x = (spd->caslat_b1 << 7) | (spd->caslat_b2 << 15) | (spd->caslat_b3 << 23); BUG_ON(spd->caslat_b4 != 0); /* * min CAS latency time */ pdimm->taa_ps = spd_to_ps(spd->taa_min, spd->fine_taa_min); /* * min RAS to CAS delay time */ pdimm->trcd_ps = spd_to_ps(spd->trcd_min, spd->fine_trcd_min); /* * Min Row Precharge Delay Time */ pdimm->trp_ps = spd_to_ps(spd->trp_min, spd->fine_trp_min); /* min active to precharge delay time */ pdimm->tras_ps = (((spd->tras_trc_ext & 0xf) << 8) + spd->tras_min_lsb) * pdimm->mtb_ps; /* min active to actice/refresh delay time */ pdimm->trc_ps = spd_to_ps((((spd->tras_trc_ext & 0xf0) << 4) + spd->trc_min_lsb), spd->fine_trc_min); /* Min Refresh Recovery Delay Time */ pdimm->trfc1_ps = ((spd->trfc1_min_msb << 8) | (spd->trfc1_min_lsb)) * pdimm->mtb_ps; pdimm->trfc2_ps = ((spd->trfc2_min_msb << 8) | (spd->trfc2_min_lsb)) * pdimm->mtb_ps; pdimm->trfc4_ps = ((spd->trfc4_min_msb << 8) | (spd->trfc4_min_lsb)) * pdimm->mtb_ps; /* min four active window delay time */ pdimm->tfaw_ps = (((spd->tfaw_msb & 0xf) << 8) | spd->tfaw_min) * pdimm->mtb_ps; /* min row active to row active delay time, different bank group */ pdimm->trrds_ps = spd_to_ps(spd->trrds_min, spd->fine_trrds_min); /* min row active to row active delay time, same bank group */ pdimm->trrdl_ps = spd_to_ps(spd->trrdl_min, spd->fine_trrdl_min); /* min CAS to CAS Delay Time (tCCD_Lmin), same bank group */ pdimm->tccdl_ps = spd_to_ps(spd->tccdl_min, spd->fine_tccdl_min); if (pdimm->package_3ds) { if (pdimm->die_density <= 0x4) { pdimm->trfc_slr_ps = 260000; } else if (pdimm->die_density <= 0x5) { pdimm->trfc_slr_ps = 350000; } else { printf("WARN: Unsupported logical rank density 0x%x\n", pdimm->die_density); } } /* * Average periodic refresh interval * tREFI = 7.8 us at normal temperature range */ pdimm->refresh_rate_ps = 7800000; for (i = 0; i < 18; i++) pdimm->dq_mapping[i] = spd->mapping[i]; pdimm->dq_mapping_ors = ((spd->mapping[0] >> 6) & 0x3) == 0 ? 1 : 0; return 0; }