src/include/memory_info.h

   1 /* Memory information */
   2 /* SPDX-License-Identifier: GPL-2.0-only */
   3
   4 #ifndef _MEMORY_INFO_H_
   5 #define _MEMORY_INFO_H_
   6
   7 #include <stdint.h>
   8
   9 #define DIMM_INFO_SERIAL_SIZE           4
  10 #define DIMM_INFO_PART_NUMBER_SIZE      33
  11 #define DIMM_INFO_TOTAL                 32
  12
  13 /**
  14  * If this table is filled and put in CBMEM,
  15  * then these info in CBMEM will be used to generate smbios type 17 table
  16  *
  17  * Values are specified according to the JEDEC SPD Standard.
  18  */
  19 struct dimm_info {
  20         /*
  21          * Size of the module in MiB.
  22          */
  23         uint32_t dimm_size;
  24         /*
  25          * SMBIOS (not SPD) device type.
  26          *
  27          * See the smbios.h smbios_memory_type enum.
  28          */
  29         uint16_t ddr_type;
  30         /*
  31          * ddr_frequency is deprecated.
  32          * Use max_speed_mts and configured_speed_mts instead.
  33          */
  34         uint16_t ddr_frequency;
  35         uint8_t rank_per_dimm;
  36         uint8_t channel_num;
  37         uint8_t dimm_num;
  38         uint8_t bank_locator;
  39         /*
  40          * SPD serial number.
  41          */
  42         uint8_t serial[DIMM_INFO_SERIAL_SIZE];
  43         /*
  44          * The last byte is '\0' for the end of string
  45          *
  46          * Must contain only printable ASCII.
  47          */
  48         uint8_t module_part_number[DIMM_INFO_PART_NUMBER_SIZE];
  49         /*
  50          * SPD Manufacturer ID
  51          */
  52         uint16_t mod_id;
  53         /*
  54          * SPD Module Type.
  55          *
  56          * See spd.h for valid values.
  57          *
  58          * e.g., SPD_RDIMM, SPD_SODIMM, SPD_MICRO_DIMM
  59          */
  60         uint8_t mod_type;
  61         /*
  62          * SPD bus width.
  63          *
  64          * Bits 0 - 2 encode the primary bus width:
  65          *   0b000 = 8 bit width
  66          *   0b001 = 16 bit width
  67          *   0b010 = 32 bit width
  68          *   0b011 = 64 bit width
  69          *
  70          * Bits 3 - 4 encode the extension bits (ECC):
  71          *   0b00 = 0 extension bits
  72          *   0b01 = 8 bit of ECC
  73          *
  74          * e.g.,
  75          *   64 bit bus with 8 bits of ECC (72 bits total): 0b1011
  76          *   64 bit bus with 0 bits of ECC (64 bits total): 0b0011
  77          *
  78          * See the smbios.h smbios_memory_bus_width enum.
  79          */
  80         uint8_t bus_width;
  81         /*
  82          * Voltage Level
  83          */
  84         uint16_t vdd_voltage;
  85         /*
  86          * Max speed in MT/s
  87          * If the value is 0, ddr_frequency should be used instead.
  88          */
  89         uint16_t max_speed_mts;
  90         /*
  91          * Configured speed in MT/s
  92          * If the value is 0, ddr_frequency should be used instead.
  93          */
  94         uint16_t configured_speed_mts;
  95 } __packed;
  96
  97 struct memory_info {
  98         /*
  99          * SMBIOS error correction type.
 100          * See the smbios.h smbios_memory_array_ecc enum.
 101          */
 102         uint8_t ecc_type;
 103         /* Maximum capacity the DRAM controller/mainboard supports */
 104         uint32_t max_capacity_mib;
 105         /* Maximum number of DIMMs the DRAM controller/mainboard supports */
 106         uint16_t number_of_devices;
 107
 108         /* active DIMM configuration */
 109         uint8_t dimm_cnt;
 110         struct dimm_info dimm[DIMM_INFO_TOTAL];
 111 } __packed;
 112
 113 /*
 114  * mainboard_get_dram_part_num returns a DRAM part number override string
 115  *  return NULL = no part number override provided by mainboard
 116  *  return non-NULL = pointer to a string terminating in '\0'
 117  */
 118 const char *mainboard_get_dram_part_num(void);
 119 #endif