1 Reply Latest reply on Oct 25, 2007 2:41 PM by joachimd

    Where can I get the reference materials about System memory address remapping?

    deanli
      There are 4 memory modules on my platform using Opteron 2210, the total capacity is 8GB, but it reports 9GB by typing "dmidecode" command. I think that's caused by memory address remapping for PCI-E or other MMIO device, is it right?
      Where can I get the reference materials about System memory address remapping?
        • Where can I get the reference materials about System memory address remapping?
          joachimd
          dmidecode reports information filled out by the BIOS to the SMBIOS DMI spec which can have neat information like which DIMMs are populated. What it sounds like you want is instead the e820 memory map which the BIOS gives the OS and can be viewed at the very beginning of the Linux kernel log with the app dmesg. IN that map one can see the remapped hole in memory for PCI access.
          e820 is an old standard from IBM and I believe this is what you are interested in. I can not find reference to it in the AMD docs as it is not specific to our processors but documentation for such things would be in the BIOS Kernel and Developer Guide or the doc AMD64 Architecture Programming Manual Volume 2: System Programming.