generic_memory_eff_attributes.xml

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<!-- @file generic_memory_eff_attributes.xml -->
<!-- @brief Calculated effective attribute definitions that are derived from SPD -->
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<attributes>

  <attribute>
    <id>ATTR_MEM_EFF_DRAM_GEN</id>
    <targetType>TARGET_TYPE_MEM_PORT</targetType>
    <description>
      ARRAY[DIMM]
      DRAM Device Type.
      Decodes SPD byte 2.
      Generation of memory: DDR3, DDR4.
    </description>
    <initToZero></initToZero>
    <valueType>uint8</valueType>
    <enum>EMPTY = 0, DDR3 = 1, DDR4 = 2</enum>
    <writeable/>
    <array>2</array>
    <mssAccessorName>dram_gen</mssAccessorName>
  </attribute>

  <attribute>
    <id>ATTR_MEM_EFF_DIMM_TYPE</id>
    <targetType>TARGET_TYPE_MEM_PORT</targetType>
    <description>
      ARRAY[DIMM]
      Base Module Type.
      Decodes SPD Byte 3 (bits 3~0).
      Type of DIMM: RDIMM, UDIMM, LRDIMM as specified by the JEDEC standard.
    </description>
    <initToZero></initToZero>
    <valueType>uint8</valueType>
    <enum> EMPTY = 0, RDIMM = 1, UDIMM = 2, LRDIMM = 3, DDIMM = 4, MDS_LRDIMM = 5, MDS = 6</enum>
    <writeable/>
    <array>2</array>
    <mssAccessorName>dimm_type</mssAccessorName>
  </attribute>

  <attribute>
    <id>ATTR_MEM_EFF_HYBRID_MEMORY_TYPE</id>
    <targetType>TARGET_TYPE_MEM_PORT</targetType>
    <description>
      ARRAY[DIMM]
      Hybrid Media.
      Decodes SPD Byte 3 (bits 6~4)
    </description>
    <initToZero></initToZero>
    <valueType>uint8</valueType>
    <enum> NONE = 0, NVDIMM = 1</enum>
    <writeable/>
    <array>2</array>
    <mssAccessorName>hybrid_memory_type</mssAccessorName>
  </attribute>

  <attribute>
    <id>ATTR_MEM_EFF_HYBRID</id>
    <targetType>TARGET_TYPE_MEM_PORT</targetType>
    <description>
      ARRAY[DIMM]
      Hybrid.
      Decodes SPD Byte 3 (bit 7)
    </description>
    <initToZero></initToZero>
    <valueType>uint8</valueType>
    <enum> NOT_HYBRID = 0, IS_HYBRID= 1</enum>
    <writeable/>
    <array>2</array>
    <mssAccessorName>hybrid</mssAccessorName>
  </attribute>

  <attribute>
    <id>ATTR_MEM_EFF_HOST_TO_DDR_SPEED_RATIO</id>
    <targetType>TARGET_TYPE_MEM_PORT</targetType>
    <description>
      ARRAY[DIMM]
      OMI to DDR frequency ratio
    </description>
    <initToZero></initToZero>
    <valueType>uint8</valueType>
    <enum> 1_TO_1 = 1, 2_TO_1 = 2, 4_TO_1 = 4, 8_TO_1 = 8, 16_TO_1 = 16, 32_TO_1 = 32, 64_TO_1 = 64, 128_TO_1 = 128</enum>
    <default>8</default>
    <writeable/>
    <array>2</array>
    <mssUnit>ratio</mssUnit>
    <mssAccessorName>host_to_ddr_speed_ratio</mssAccessorName>
  </attribute>

  <attribute>
    <id>ATTR_MEM_EFF_DRAM_DENSITY</id>
    <targetType>TARGET_TYPE_MEM_PORT</targetType>
    <description>
      ARRAY[DIMM]
      DRAM Density.
      Decodes SPD Byte 4 (bits 3~0).
      Total SDRAM capacity per die.
      For multi-die stacks (DDP, QDP, or 3DS), this represents
      the capacity of each DRAM die in the stack.
    </description>
    <initToZero></initToZero>
    <valueType>uint8</valueType>
    <enum> 4G = 4, 8G = 8, 16G = 16 </enum>
    <writeable/>
    <array>2</array>
    <mssUnit>Gb</mssUnit>
    <mssAccessorName>dram_density</mssAccessorName>
  </attribute>

  <attribute>
    <id>ATTR_MEM_EFF_DRAM_BANK_BITS</id>
    <targetType>TARGET_TYPE_MEM_PORT</targetType>
    <description>
      ARRAY[DIMM]
      Number of DRAM bank address bits.
      Actual number of banks is 2^N, where
      N is the number of bank address bits.
      Decodes SPD Byte 4 (bits 5~4).
    </description>
    <initToZero></initToZero>
    <valueType>uint8</valueType>
    <writeable/>
    <array>2</array>
    <mssAccessorName>dram_bank_bits</mssAccessorName>
  </attribute>

  <attribute>
    <id>ATTR_MEM_EFF_DRAM_BANK_GROUP_BITS</id>
    <targetType>TARGET_TYPE_MEM_PORT</targetType>
    <description>
      ARRAY[DIMM]
      Bank Groups Bits.
      Decoded SPD Byte 4 (bits 7~6).
      Actual number of bank groups is 2^N,
      where N is the number of bank address bits.
      This value represents the number of bank groups
      into which the memory array is divided.
    </description>
    <initToZero></initToZero>
    <valueType>uint8</valueType>
    <writeable/>
    <array>2</array>
    <mssAccessorName>dram_bank_group_bits</mssAccessorName>
  </attribute>

  <attribute>
    <id>ATTR_MEM_EFF_DRAM_COLUMN_BITS</id>
    <targetType>TARGET_TYPE_MEM_PORT</targetType>
    <description>
      ARRAY[DIMM]
      Column Address Bits.
      Decoded SPD Byte 5 (bits 2~0).
      Actual number of DRAM columns is 2^N,
      where N is the number of column address bits
    </description>
    <initToZero></initToZero>
    <valueType>uint8</valueType>
    <enum> NUM10 = 10</enum>
    <writeable/>
    <array>2</array>
    <mssAccessorName>dram_column_bits</mssAccessorName>
  </attribute>

  <attribute>
    <id>ATTR_MEM_EFF_DRAM_ROW_BITS</id>
    <targetType>TARGET_TYPE_MEM_PORT</targetType>
    <description>
      ARRAY[DIMM]
      Row Address Bits.
      Decodes Byte 5 (bits 5~3).
      Number of DRAM column address bits.
      Actual number of DRAM rows is 2^N,
      where N is the number of row address bits
    </description>
    <initToZero></initToZero>
    <valueType>uint8</valueType>
    <enum> NUM14 = 14, NUM15 = 15, NUM16 = 16, NUM17 = 17, NUM18 = 18</enum>
    <writeable/>
    <array>2</array>
    <mssAccessorName>dram_row_bits</mssAccessorName>
  </attribute>

  <attribute>
    <id>ATTR_MEM_EFF_PRIM_DIE_COUNT</id>
    <targetType>TARGET_TYPE_MEM_PORT</targetType>
    <description>
      ARRAY[DIMM]
      Primary SDRAM Die Count.
      Decodes Byte 6 (bits 6~4).
    </description>
    <initToZero></initToZero>
    <valueType>uint8</valueType>
    <enum>
      D1 = 1,
      D2 = 2,
      D3 = 3,
      D4 = 4,
      D5 = 5,
      D6 = 6,
      D7 = 7,
      D8 = 8
    </enum>
    <writeable/>
    <array>2</array>
    <mssAccessorName>prim_die_count</mssAccessorName>
  </attribute>

  <attribute>
    <id>ATTR_MEM_EFF_PRIM_STACK_TYPE</id>
    <targetType>TARGET_TYPE_MEM_PORT</targetType>
    <description>
      ARRAY[DIMM]
      Primary SDRAM Package Type (bits 1~0).
      Decodes Byte 6.
      This byte defines the primary set of SDRAMs.
      Monolithic = SPD, Multi-load stack = DDP/QDP, Single-load stack = 3DS
    </description>
    <initToZero></initToZero>
    <valueType>uint8</valueType>
    <enum> SDP = 0, DDP_QDP = 1, 3DS = 2</enum>
    <writeable/>
    <array>2</array>
    <mssAccessorName>prim_stack_type</mssAccessorName>
  </attribute>

  <attribute>
    <id>ATTR_MEM_EFF_PRIM_BUS_WIDTH</id>
    <targetType>TARGET_TYPE_MEM_PORT</targetType>
    <description>
      ARRAY[DIMM]
      Primary bus with (bits 1~0).
      Decodes Byte 13.
    </description>
    <initToZero></initToZero>
    <valueType>uint8</valueType>
    <enum>
      8_BITS = 8, 16_BITS = 16, 32_BITS = 32, 64_BITS = 64
    </enum>
    <writeable/>
    <array>2</array>
    <mssAccessorName>prim_bus_width</mssAccessorName>
  </attribute>

  <attribute>
    <id>ATTR_MEM_EFF_DRAM_PPR</id>
    <targetType>TARGET_TYPE_MEM_PORT</targetType>
    <description>
      ARRAY[DIMM]
      Post Package Repair. Used in various locations and is evaluated in mss_eff_cnfg.
    </description>
    <initToZero></initToZero>
    <valueType>uint8</valueType>
    <enum>NOT_SUPPORTED = 0, SUPPORTED = 1</enum>
    <writeable/>
    <array>2</array>
    <mssAccessorName>dram_ppr</mssAccessorName>
  </attribute>

  <attribute>
    <id>ATTR_MEM_EFF_DRAM_SOFT_PPR</id>
    <targetType>TARGET_TYPE_MEM_PORT</targetType>
    <description>
      ARRAY[DIMM]
      Soft Post Package Repair. Used in various locations and is evaluated in mss_eff_cnfg.
    </description>
    <initToZero></initToZero>
    <valueType>uint8</valueType>
    <enum>NOT_SUPPORTED = 0, SUPPORTED = 1</enum>
    <writeable/>
    <array>2</array>
    <mssAccessorName>dram_soft_ppr</mssAccessorName>
  </attribute>

  <attribute>
    <id>ATTR_MEM_EFF_DRAM_TRCD</id>
    <targetType>TARGET_TYPE_MEM_PORT</targetType>
    <description>
      Minimum RAS to CAS Delay Time
      in nck (number of clock cyles).
      Decodes SPD byte 25 (7~0) and byte 112 (7~0).
      Each memory channel will have a value.
    </description>
    <initToZero></initToZero>
    <valueType>uint8</valueType>
    <writeable/>
    <mssUnits> nck </mssUnits>
    <mssAccessorName>dram_trcd</mssAccessorName>
  </attribute>

  <attribute>
    <id>ATTR_MEM_EFF_DRAM_TRP</id>
    <targetType>TARGET_TYPE_MEM_PORT</targetType>
    <description>
      SDRAM Row Precharge Delay Time
      in nck (number of clock cycles).
      Decodes SPD byte 26 (bits 7~0) and byte 121 (bits 7~0).
      Each memory channel will have a value.
    </description>
    <initToZero></initToZero>
    <valueType>uint8</valueType>
    <writeable/>
    <mssUnits> nck </mssUnits>
    <mssAccessorName>dram_trp</mssAccessorName>
  </attribute>

  <attribute>
    <id>ATTR_MEM_EFF_DRAM_TRAS</id>
    <targetType>TARGET_TYPE_MEM_PORT</targetType>
    <description>
      Minimum Active to Precharge Delay Time
      in nck (number of clock cycles).
      Decodes SPD byte 27 (bits 3~0) and byte 28 (7~0).
      Each memory channel will have a value.
      creator: mss_eff_cnfg_timing
    </description>
    <initToZero></initToZero>
    <valueType>uint8</valueType>
    <writeable/>
    <mssUnits> nck </mssUnits>
    <mssAccessorName>dram_tras</mssAccessorName>
  </attribute>

  <attribute>
    <id>ATTR_MEM_EFF_DRAM_TRC</id>
    <targetType>TARGET_TYPE_MEM_PORT</targetType>
    <description>
      Minimum Active to Active/Refresh Delay
      in nck (number of clock cyles).
      Decodes SPD byte 27 (bits 7~4), byte 29 (bits 7~0), and byte 120.
      Each memory channel will have a value.
    </description>
    <initToZero></initToZero>
    <valueType>uint8</valueType>
    <writeable/>
    <mssUnits> nck </mssUnits>
    <mssAccessorName>dram_trc</mssAccessorName>
  </attribute>

  <attribute>
    <id>ATTR_MEM_EFF_DRAM_TRFC</id>
    <targetType>TARGET_TYPE_MEM_PORT</targetType>
    <description>
      DDR4 Spec defined as Refresh Cycle Time (tRFC).
      SPD Spec refers it to the Minimum Refresh Recovery Delay Time.
      In nck (number of clock cyles).
      Decodes SPD byte 31 (bits 15~8) and byte 30 (bits 7~0) for tRFC1.
      Decodes SPD byte 33 (bits 15~8) and byte 32 (bits 7~0) for tRFC2.
      Decodes SPD byte 35 (bits 15~8) and byte 34 (bits 7~0) for tRFC4.
      Selected tRFC value depends on MRW attribute that selects refresh mode.
      For 3DS, The tRFC time to the same logical rank is defined as tRFC_slr and is
      specificed as the value as for a monolithic DDR4 SDRAM of equivalent density.
    </description>
    <initToZero></initToZero>
    <valueType>uint16</valueType>
    <writeable/>
    <mssUnits> nck </mssUnits>
    <mssAccessorName>dram_trfc</mssAccessorName>
  </attribute>

  <attribute>
    <id>ATTR_MEM_EFF_DRAM_TFAW</id>
    <targetType>TARGET_TYPE_MEM_PORT</targetType>
    <description>
      Minimum Four Activate Window Delay Time
      in nck (number of clock cycles).
      Decodes SPD byte 36 (bits 3~0) and byte 37 (bits 7~0).
      For 3DS, tFAW time to the same logical rank is defined as
      tFAW_slr_x4 or tFAW_slr_x8 (for x4 and x8 devices only) and
      specificed as the value as for a monolithic DDR4 SDRAM
      equivalent density.
      Each memory channel will have a value.
    </description>
    <initToZero></initToZero>
    <valueType>uint8</valueType>
    <writeable/>
    <mssUnits> nck </mssUnits>
    <mssAccessorName>dram_tfaw</mssAccessorName>
  </attribute>

  <attribute>
    <id>ATTR_MEM_EFF_DRAM_TRRD_S</id>
    <targetType>TARGET_TYPE_MEM_PORT</targetType>
    <description>
      Minimum Activate to Activate Delay Time, different bank group
      in nck (number of clock cycles).
      Decodes SPD byte 38 (bits 7~0).
      For 3DS, The tRRD_S time to a different bank group in the
      same logical rank is defined as tRRD_slr and is
      specificed as the value as for a monolithic
      DDR4 SDRAM of equivalent density.
      Each memory channel will have a value.
    </description>
    <initToZero></initToZero>
    <valueType>uint8</valueType>
    <writeable/>
    <mssUnits> nck </mssUnits>
    <mssAccessorName>dram_trrd_s</mssAccessorName>
  </attribute>

  <attribute>
    <id>ATTR_MEM_EFF_DRAM_TRRD_L</id>
    <targetType>TARGET_TYPE_MEM_PORT</targetType>
    <description>
      Minimum Activate to Activate Delay Time, same bank group
      in nck (number of clock cycles).
      Decodes SPD byte 39 (bits 7~0).
      For 3DS, The tRRD_L time to the same bank group in the
      same logical rank is defined as tRRD_L_slr and is
      specificed as the value as for a monolithic
      DDR4 SDRAM of equivalent density.
      Each memory channel will have a value.
    </description>
    <initToZero></initToZero>
    <valueType>uint8</valueType>
    <writeable/>
    <mssUnits> nck </mssUnits>
    <mssAccessorName>dram_trrd_l</mssAccessorName>
  </attribute>

  <attribute>
    <id>ATTR_MEM_EFF_DRAM_TRRD_DLR</id>
    <targetType>TARGET_TYPE_MEM_PORT</targetType>
    <description>
      Minimum Activate to Activate Delay Time (different logical ranks)
      in nck (number of clock cycles).
      For 3DS, The tRRD_S time to a different logical rank is defined as tRRD_dlr.
      Each memory channel will have a value.
    </description>
    <initToZero></initToZero>
    <valueType>uint8</valueType>
    <writeable/>
    <mssUnits> nck </mssUnits>
    <mssAccessorName>dram_trrd_dlr</mssAccessorName>
  </attribute>

  <attribute>
    <id>ATTR_MEM_EFF_DRAM_TCCD_L</id>
    <targetType>TARGET_TYPE_MEM_PORT</targetType>
    <description>
      Minimum CAS to CAS Delay Time, same bank group
      in nck (number of clock cycles).
      Decodes SPD byte 40 (bits 7~0) and byte 117 (bits 7~0).
      This is for DDR4 MRS6.
      Each memory channel will have a value.
    </description>
    <initToZero></initToZero>
    <valueType>uint8</valueType>
    <enum>4NCK = 4, 5NCK = 5, 6NCK = 6, 7NCK = 7, 8NCK = 8</enum>
    <writeable/>
    <mssUnits> nck </mssUnits>
    <mssAccessorName>dram_tccd_l</mssAccessorName>
  </attribute>

  <attribute>
    <id>ATTR_MEM_EFF_DRAM_TWR</id>
    <targetType>TARGET_TYPE_MEM_PORT</targetType>
    <description>
      Minimum Write Recovery Time.
      Decodes SPD byte 41 (bits 3~0) and byte 42 (bits 7~0).
      Each memory channel will have a value.
    </description>
    <initToZero></initToZero>
    <valueType>uint8</valueType>
    <writeable/>
    <mssUnits> nck </mssUnits>
    <mssAccessorName>dram_twr</mssAccessorName>
  </attribute>

  <attribute>
    <id>ATTR_MEM_EFF_DRAM_TWTR_S</id>
    <targetType>TARGET_TYPE_MEM_PORT</targetType>
    <description>
      Minimum Write to Read Time, different bank group
      in nck (number of clock cycles).
      Decodes SPD byte 43 (3~0) and byte 44 (bits 7~0).
      Each memory channel will have a value.
    </description>
    <initToZero></initToZero>
    <valueType>uint8</valueType>
    <writeable/>
    <mssUnits> nck </mssUnits>
    <mssAccessorName>dram_twtr_s</mssAccessorName>
  </attribute>

  <attribute>
    <id>ATTR_MEM_EFF_DRAM_TWTR_L</id>
    <targetType>TARGET_TYPE_MEM_PORT</targetType>
    <description>
      Minimum Write to Read Time, same bank group
      in nck (number of clock cycles).
      Decodes byte 43 (7~4) and byte 45 (bits 7~0).
      Each memory channel will have a value.
    </description>
    <initToZero></initToZero>
    <valueType>uint8</valueType>
    <writeable/>
    <mssUnits> nck </mssUnits>
    <mssAccessorName>dram_twtr_l</mssAccessorName>
  </attribute>

  <attribute>
    <id>ATTR_MEM_EFF_DRAM_TMAW</id>
    <targetType>TARGET_TYPE_MEM_PORT</targetType>
    <description>
      Maximum Activate Window
      in nck (number of clock cycles).
      Decodes SPD byte 7 (bits 5~4).
      Depends on tREFI multiplier.
      Each memory channel will have a value.
    </description>
    <initToZero></initToZero>
    <valueType>uint16</valueType>
    <writeable/>
    <mssUnits> nck </mssUnits>
    <mssAccessorName>dram_tmaw</mssAccessorName>
  </attribute>

  <attribute>
    <id>ATTR_MEM_EFF_DRAM_WIDTH</id>
    <targetType>TARGET_TYPE_MEM_PORT</targetType>
    <description>
      ARRAY[DIMM]
      SDRAM Device Width
      Decodes SPD Byte 12 (bits 2~0).
      Options: X4 (4 bits), X8 (8 bits), X16 (16 bits), X32 (32 bits).
    </description>
    <initToZero></initToZero>
    <valueType>uint8</valueType>
    <enum>X4 = 4, X8 = 8, X16 = 16, X32 = 32</enum>
    <mssUnit>bits</mssUnit>
    <writeable/>
    <array>2</array>
    <mssAccessorName>dram_width</mssAccessorName>
  </attribute>

  <attribute>
    <id>ATTR_MEM_EFF_LOGICAL_RANKS_PER_DIMM</id>
    <targetType>TARGET_TYPE_MEM_PORT</targetType>
    <description>
      ARRAY[DIMM]
      Total number of ranks in each DIMM.
      For monolithic and multi-load stack modules (SDP/DDP) this is the same as
      the number of package ranks per DIMM (SPD Byte 12 bits 5~3).

      For single load stack (3DS) modules this value represents the number
      of logical ranks per DIMM.
      Logical rank refers the individually addressable die in a 3DS stack
      and has no meaning for monolithic or multi-load stacked SDRAMs.
    </description>
    <initToZero></initToZero>
    <valueType>uint8</valueType>
    <enum>
      1R = 1, 2R = 2, 4R = 4, 8R = 8, 16R = 16
    </enum>
    <writeable/>
    <array>2</array>
    <mssAccessorName>logical_ranks_per_dimm</mssAccessorName>
  </attribute>

    <attribute>
      <id>ATTR_MEM_3DS_HEIGHT</id>
      <targetType>TARGET_TYPE_MEM_PORT</targetType>
      <description>
        Setting for 3DS stack. Calculated from logical_ranks / master_ranks
      </description>
      <initToZero></initToZero>
      <valueType>uint16</valueType>
      <enum>PLANAR = 0, H2 = 2, H4 = 4, H8 = 8</enum>
      <array>2</array>
      <writeable/>
      <mssAccessorName>3ds_height</mssAccessorName>
  </attribute>

  <attribute>
    <id>ATTR_MEM_EFF_REGISTER_TYPE</id>
    <targetType>TARGET_TYPE_MEM_PORT</targetType>
    <description>
      ARRAY[DIMM]
      Register Type
      Decodes SPD Byte 131
    </description>
    <enum>RCD01 = 0x0, RCD02 = 0x1</enum>
    <initToZero></initToZero>
    <valueType>uint8</valueType>
    <writeable/>
    <array>2</array>
    <mssAccessorName>register_type</mssAccessorName>
  </attribute>

  <attribute>
    <id>ATTR_MEM_EFF_DRAM_MFG_ID</id>
    <targetType>TARGET_TYPE_MEM_PORT</targetType>
    <description>
      ARRAY[DIMM]
      DRAM Manufacturer ID Code
      Decodes SPD Byte 350 and 351 for ISDIMMs
      Decodes SPD Byte 552 and 553 for DDIMMs
    </description>
    <enum>MICRON = 0x802C, SAMSUNG = 0x80CE, HYNIX = 0x80AD </enum>
    <initToZero></initToZero>
    <valueType>uint16</valueType>
    <writeable/>
    <array>2</array>
    <mssAccessorName>dram_mfg_id</mssAccessorName>
  </attribute>

  <attribute>
    <id>ATTR_MEM_EFF_DRAM_MODULE_HEIGHT</id>
    <targetType>TARGET_TYPE_OCMB_CHIP</targetType>
    <description>
      ARRAY[DIMM]
      DRAM Modlue Height
      Decodes SPD Byte 193
    </description>
    <enum>1U = 0, 2U = 1, 4U = 2 </enum>
    <initToZero></initToZero>
    <valueType>uint8</valueType>
    <writeable/>
    <mssAccessorName>dram_module_height</mssAccessorName>
  </attribute>

  <attribute>
    <id>ATTR_MEM_EFF_RCD_MFG_ID</id>
    <targetType>TARGET_TYPE_MEM_PORT</targetType>
    <description>
      ARRAY[DIMM]
      Register Manufacturer ID Code
      Decodes SPD Byte 133 and 134
    </description>
    <enum>INPHI = 0xB304, MONTAGE = 0x3286, IDT = 0xB380 </enum>
    <initToZero></initToZero>
    <valueType>uint16</valueType>
    <writeable/>
    <array>2</array>
    <mssAccessorName>rcd_mfg_id</mssAccessorName>
  </attribute>

  <attribute>
    <id>ATTR_MEM_EFF_REGISTER_REV</id>
    <targetType>TARGET_TYPE_MEM_PORT</targetType>
    <description>
      ARRAY[DIMM]
      Register Revision Number
      Decodes SPD Byte 135
    </description>
    <initToZero></initToZero>
    <valueType>uint8</valueType>
    <writeable/>
    <array>2</array>
    <mssAccessorName>register_rev</mssAccessorName>
  </attribute>

  <attribute>
    <id>ATTR_MEM_EFF_PACKAGE_RANK_MAP</id>
    <targetType>TARGET_TYPE_MEM_PORT</targetType>
    <description>
      ARRAY[DIMM][DQ_NIBBLES]
      Package Rank Map
      Decodes SPD Byte 60 - 77 (Bits 7~6)
    </description>
    <initToZero></initToZero>
    <valueType>uint8</valueType>
    <writeable/>
    <array>2 20</array>
    <mssAccessorName>package_rank_map</mssAccessorName>
  </attribute>

  <attribute>
    <id>ATTR_MEM_EFF_NIBBLE_MAP</id>
    <targetType>TARGET_TYPE_MEM_PORT</targetType>
    <description>
      ARRAY[DIMM][DQ_NIBBLES]
      Nibble Map
      Decodes SPD Byte 60 - 77 (Bits 5~0) for DDR4
    </description>
    <initToZero></initToZero>
    <valueType>uint8</valueType>
    <writeable/>
    <array>2 20</array>
    <mssAccessorName>nibble_map</mssAccessorName>
  </attribute>

  <attribute>
    <id>ATTR_MEM_EFF_DIMM_SIZE</id>
    <targetType>TARGET_TYPE_MEM_PORT</targetType>
    <description>
      ARRAY[DIMM]
      DIMM Size, in GB Used in various locations
    </description>
    <initToZero></initToZero>
    <valueType>uint32</valueType>
    <enum>
      4GB = 4,
      8GB = 8,
      16GB = 16,
      32GB = 32,
      64GB = 64,
      128GB = 128,
      256GB = 256,
      512GB = 512
    </enum>
    <writeable/>
    <array>2</array>
    <mssUnits>GB</mssUnits>
    <mssAccessorName>dimm_size</mssAccessorName>
  </attribute>

  <attribute>
    <id>ATTR_MEM_EFF_DIMM_SPARE</id>
    <targetType>TARGET_TYPE_MEM_PORT</targetType>
    <description>
      Spare DRAM availability. Used in various locations and is computed in mss_eff_cnfg.
      Array indexes are [DIMM][RANK]
    </description>
    <initToZero></initToZero>
    <valueType>uint8</valueType>
    <enum>NO_SPARE = 0, LOW_NIBBLE = 1, HIGH_NIBBLE = 2, FULL_BYTE = 3</enum>
    <writeable/>
    <array> 2 4</array>
    <mssAccessorName>dimm_spare</mssAccessorName>
  </attribute>

  <attribute>
    <id>ATTR_MEM_EFF_DRAM_CL</id>
    <targetType>TARGET_TYPE_MEM_PORT</targetType>
    <description>
      CAS Latency.
      Each memory channel will have a value.
    </description>
    <initToZero></initToZero>
    <valueType>uint8</valueType>
    <writeable/>
    <mssUnits>nck</mssUnits>
    <mssAccessorName>dram_cl</mssAccessorName>
  </attribute>

  <attribute>
    <id>ATTR_MEM_EFF_DRAM_MDS</id>
    <targetType>TARGET_TYPE_MEM_PORT</targetType>
    <description>
      Controls if the given target has an MDS (managed DRAM solution)
    </description>
    <initToZero></initToZero>
    <valueType>uint8</valueType>
    <writeable/>
    <mssAccessorName>dram_mds</mssAccessorName>
  </attribute>

  <attribute>
    <id>ATTR_MEM_EFF_NUM_MASTER_RANKS_PER_DIMM</id>
    <targetType>TARGET_TYPE_MEM_PORT</targetType>
    <description>
      ARRAY[DIMM]
      Specifies the number of master ranks per DIMM.
      Represents the number of physical ranks on a DIMM.
      From SPD spec JEDEC Standard No. 21-C: Page 4.1.2.L-4.
      Byte 12 (Bits 5~3) Number of package ranks per DIMM.
      Package ranks per DIMM refers to the collections of devices
      on the module sharing common chip select signals.
    </description>
    <initToZero></initToZero>
    <valueType>uint8</valueType>
    <enum>
      1R = 1, 2R = 2, 4R = 4, 8R = 8
    </enum>
    <writeable/>
    <array>2</array>
    <mssAccessorName>num_master_ranks_per_dimm</mssAccessorName>
  </attribute>

  <attribute>
    <id>ATTR_MEM_EFF_DIMM_RANKS_CONFIGED</id>
    <targetType>TARGET_TYPE_MEM_PORT</targetType>
    <description>
      Bit wise representation of master ranks in each DIMM that are used for reads and writes.
      Used by PRD.
    </description>
    <initToZero></initToZero>
    <valueType>uint8</valueType>
    <writeable/>
    <array> 2 </array>
    <mssAccessorName>dimm_ranks_configed</mssAccessorName>
  </attribute>

  <attribute>
    <id>ATTR_MEM_EFF_DRAM_TREFI</id>
    <targetType>TARGET_TYPE_MEM_PORT</targetType>
    <description>
      Average Refresh Interval (tREFI)
      in nck (number of clock cycles).
      This depends on MRW attribute that selects fine refresh mode (x1, x2, x4).
      From DDR4 spec (79-4A).

      For 3DS, the tREFI time to the same logical rank is defined as
      tRFC_slr1, tRFC_slr2, or tRFC_slr4.
    </description>
    <initToZero></initToZero>
    <valueType>uint16</valueType>
    <writeable/>
    <mssUnits> nck </mssUnits>
    <mssAccessorName>dram_trefi</mssAccessorName>
  </attribute>

  <attribute>
    <id>ATTR_MEM_EFF_DRAM_TRTP</id>
    <targetType>TARGET_TYPE_MEM_PORT</targetType>
    <description>
      Internal Read to Precharge Delay.
      From the DDR4 spec (79-4A).
      Each memory channel will have a value.
    </description>
    <initToZero></initToZero>
    <valueType>uint8</valueType>
    <writeable/>
    <mssUnits>nck</mssUnits>
    <mssAccessorName>dram_trtp</mssAccessorName>
  </attribute>

  <attribute>
    <id>ATTR_MEM_EFF_DRAM_TRFC_DLR</id>
    <targetType>TARGET_TYPE_MEM_PORT</targetType>
    <description>
      Minimum Refresh Recovery Delay Time (different logical ranks)
      in nck (number of clock cyles).
      Selected tRFC value (tRFC_dlr1, tRFC_dlr2, or tRFC_dlr4)
      depends on MRW attribute that selects fine refresh mode (x1, x2, x4).
      For 3DS, The tRFC time to different logical ranks are defined as tRFC_dlr
    </description>
    <initToZero></initToZero>
    <valueType>uint16</valueType>
    <writeable/>
    <mssUnits> nck </mssUnits>
    <mssAccessorName>dram_trfc_dlr</mssAccessorName>
  </attribute>

  <attribute>
    <id>ATTR_MEM_EFF_FREQ</id>
    <targetType>TARGET_TYPE_MEM_PORT</targetType>
    <description>
      Frequency of this memory channel in MT/s (Mega Transfers per second)
    </description>
    <initToZero></initToZero>
    <valueType>uint64</valueType>
    <writeable/>
    <mssUnits> MT/s </mssUnits>
    <mssAccessorName>freq</mssAccessorName>
  </attribute>

  <attribute>
    <id>ATTR_MEM_EFF_VOLT_VDDR</id>
    <targetType>TARGET_TYPE_OCMB_CHIP</targetType>
    <description>
      DRAM Voltage, each voltage rail would need to have a value.
    </description>
    <initToZero></initToZero>
    <valueType>uint32</valueType>
    <writeable/>
    <mssUnits> mV </mssUnits>
    <mssAccessorName>volt_vddr</mssAccessorName>
  </attribute>

  <attribute>
    <id>ATTR_MEM_EFF_VOLT_VPP</id>
    <targetType>TARGET_TYPE_OCMB_CHIP</targetType>
    <description>
      DRAM VPP Voltage, each voltage rail would need to have a value.
    </description>
    <initToZero></initToZero>
    <valueType>uint32</valueType>
    <writeable/>
    <mssUnits> mV </mssUnits>
    <mssAccessorName>volt_vpp</mssAccessorName>
  </attribute>

  <attribute>
    <id>ATTR_MEM_EFF_SPD_REVISION</id>
    <targetType>TARGET_TYPE_MEM_PORT</targetType>
    <description>
      SPD Revision (SPD Byte 1)
    </description>
    <initToZero></initToZero>
    <valueType>uint8</valueType>
    <writeable/>
    <mssAccessorName>spd_revision</mssAccessorName>
  </attribute>

</attributes>