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Diffstat (limited to 'Documentation/ABI/testing/sysfs-firmware-memmap')
| -rw-r--r-- | Documentation/ABI/testing/sysfs-firmware-memmap | 71 |
1 files changed, 0 insertions, 71 deletions
diff --git a/Documentation/ABI/testing/sysfs-firmware-memmap b/Documentation/ABI/testing/sysfs-firmware-memmap deleted file mode 100644 index eca0d65..0000000 --- a/Documentation/ABI/testing/sysfs-firmware-memmap +++ /dev/null @@ -1,71 +0,0 @@ -What: /sys/firmware/memmap/ -Date: June 2008 -Contact: Bernhard Walle <bernhard.walle@gmx.de> -Description: - On all platforms, the firmware provides a memory map which the - kernel reads. The resources from that memory map are registered - in the kernel resource tree and exposed to userspace via - /proc/iomem (together with other resources). - - However, on most architectures that firmware-provided memory - map is modified afterwards by the kernel itself, either because - the kernel merges that memory map with other information or - just because the user overwrites that memory map via command - line. - - kexec needs the raw firmware-provided memory map to setup the - parameter segment of the kernel that should be booted with - kexec. Also, the raw memory map is useful for debugging. For - that reason, /sys/firmware/memmap is an interface that provides - the raw memory map to userspace. - - The structure is as follows: Under /sys/firmware/memmap there - are subdirectories with the number of the entry as their name: - - /sys/firmware/memmap/0 - /sys/firmware/memmap/1 - /sys/firmware/memmap/2 - /sys/firmware/memmap/3 - ... - - The maximum depends on the number of memory map entries provided - by the firmware. The order is just the order that the firmware - provides. - - Each directory contains three files: - - start : The start address (as hexadecimal number with the - '0x' prefix). - end : The end address, inclusive (regardless whether the - firmware provides inclusive or exclusive ranges). - type : Type of the entry as string. See below for a list of - valid types. - - So, for example: - - /sys/firmware/memmap/0/start - /sys/firmware/memmap/0/end - /sys/firmware/memmap/0/type - /sys/firmware/memmap/1/start - ... - - Currently following types exist: - - - System RAM - - ACPI Tables - - ACPI Non-volatile Storage - - reserved - - Following shell snippet can be used to display that memory - map in a human-readable format: - - -------------------- 8< ---------------------------------------- - #!/bin/bash - cd /sys/firmware/memmap - for dir in * ; do - start=$(cat $dir/start) - end=$(cat $dir/end) - type=$(cat $dir/type) - printf "%016x-%016x (%s)\n" $start $[ $end +1] "$type" - done - -------------------- >8 ---------------------------------------- |