efi: Export more EFI table variables to sysfs

Export fw_vendor, runtime and config table physical addresses to
/sys/firmware/efi/{fw_vendor,runtime,config_table} because kexec kernels
need them.

From EFI spec these 3 variables will be updated to virtual address after
entering virtual mode. But kernel startup code will need the physical
address.

Signed-off-by: Dave Young <dyoung@redhat.com>
Tested-by: Toshi Kani <toshi.kani@hp.com>
Signed-off-by: Matt Fleming <matt.fleming@intel.com>

1 files changed, 20 insertions, 0 deletions

diff --git a/Documentation/ABI/testing/sysfs-firmware-efi b/Documentation/ABI/testing/sysfs-firmware-efi
new file mode 100644
index 000000000000..05874da7ce80
--- /dev/null
+++ b/Documentation/ABI/testing/sysfs-firmware-efi
@@ -0,0 +1,20 @@
+What:           /sys/firmware/efi/fw_vendor
+Date:           December 2013
+Contact:        Dave Young <dyoung@redhat.com>
+Description:    It shows the physical address of firmware vendor field in the
+                EFI system table.
+Users:          Kexec
+
+What:           /sys/firmware/efi/runtime
+Date:           December 2013
+Contact:        Dave Young <dyoung@redhat.com>
+Description:    It shows the physical address of runtime service table entry in
+                the EFI system table.
+Users:          Kexec
+
+What:           /sys/firmware/efi/config_table
+Date:           December 2013
+Contact:        Dave Young <dyoung@redhat.com>
+Description:    It shows the physical address of config table entry in the EFI
+                system table.
+Users:          Kexec