Add the rt linux 4.1.3-rt3 as base

[kvmfornfv.git] / kernel / Documentation / ABI / testing / sysfs-firmware-efi-runtime-map

diff --git a/kernel/Documentation/ABI/testing/sysfs-firmware-efi-runtime-map b/kernel/Documentation/ABI/testing/sysfs-firmware-efi-runtime-map
new file mode 100644 (file)
index 0000000..c61b9b3
--- /dev/null
+++ b/kernel/Documentation/ABI/testing/sysfs-firmware-efi-runtime-map
@@ -0,0 +1,34 @@
+What:          /sys/firmware/efi/runtime-map/
+Date:          December 2013
+Contact:       Dave Young <dyoung@redhat.com>
+Description:   Switching efi runtime services to virtual mode requires
+               that all efi memory ranges which have the runtime attribute
+               bit set to be mapped to virtual addresses.
+
+               The efi runtime services can only be switched to virtual
+               mode once without rebooting. The kexec kernel must maintain
+               the same physical to virtual address mappings as the first
+               kernel. The mappings are exported to sysfs so userspace tools
+               can reassemble them and pass them into the kexec kernel.
+
+               /sys/firmware/efi/runtime-map/ is the directory the kernel
+               exports that information in.
+
+               subdirectories are named with the number of the memory range:
+
+                       /sys/firmware/efi/runtime-map/0
+                       /sys/firmware/efi/runtime-map/1
+                       /sys/firmware/efi/runtime-map/2
+                       /sys/firmware/efi/runtime-map/3
+                       ...
+
+               Each subdirectory contains five files:
+
+               attribute : The attributes of the memory range.
+               num_pages : The size of the memory range in pages.
+               phys_addr : The physical address of the memory range.
+               type      : The type of the memory range.
+               virt_addr : The virtual address of the memory range.
+
+               Above values are all hexadecimal numbers with the '0x' prefix.
+Users:         Kexec