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author | Linus Torvalds <torvalds@linux-foundation.org> | 2008-07-14 13:43:24 -0700 |
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committer | Linus Torvalds <torvalds@linux-foundation.org> | 2008-07-14 13:43:24 -0700 |
commit | a3da5bf84a97d48cfaf66c6842470fc403da5121 (patch) | |
tree | cdf66c0cff8c61eedd60601fc9dffdd1ed39b880 /Documentation/ABI | |
parent | 3b23e665b68387f5ee7b21f7b75ceea4d9acae4a (diff) | |
parent | d59fdcf2ac501de99c3dfb452af5e254d4342886 (diff) | |
download | lwn-a3da5bf84a97d48cfaf66c6842470fc403da5121.tar.gz lwn-a3da5bf84a97d48cfaf66c6842470fc403da5121.zip |
Merge branch 'x86/for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip
* 'x86/for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip: (821 commits)
x86: make 64bit hpet_set_mapping to use ioremap too, v2
x86: get x86_phys_bits early
x86: max_low_pfn_mapped fix #4
x86: change _node_to_cpumask_ptr to return const ptr
x86: I/O APIC: remove an IRQ2-mask hack
x86: fix numaq_tsc_disable calling
x86, e820: remove end_user_pfn
x86: max_low_pfn_mapped fix, #3
x86: max_low_pfn_mapped fix, #2
x86: max_low_pfn_mapped fix, #1
x86_64: fix delayed signals
x86: remove conflicting nx6325 and nx6125 quirks
x86: Recover timer_ack lost in the merge of the NMI watchdog
x86: I/O APIC: Never configure IRQ2
x86: L-APIC: Always fully configure IRQ0
x86: L-APIC: Set IRQ0 as edge-triggered
x86: merge dwarf2 headers
x86: use AS_CFI instead of UNWIND_INFO
x86: use ignore macro instead of hash comment
x86: use matching CFI_ENDPROC
...
Diffstat (limited to 'Documentation/ABI')
-rw-r--r-- | Documentation/ABI/testing/sysfs-firmware-memmap | 71 |
1 files changed, 71 insertions, 0 deletions
diff --git a/Documentation/ABI/testing/sysfs-firmware-memmap b/Documentation/ABI/testing/sysfs-firmware-memmap new file mode 100644 index 000000000000..0d99ee6ae02e --- /dev/null +++ b/Documentation/ABI/testing/sysfs-firmware-memmap @@ -0,0 +1,71 @@ +What: /sys/firmware/memmap/ +Date: June 2008 +Contact: Bernhard Walle <bwalle@suse.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 ---------------------------------------- |