SFI: add sysfs interface for SFI tables.

Analogous to ACPI's /sys/firmware/acpi/tables/...

create /sys/firmware/sfi/tables/

The tables are primariy for the kernel,
but sometimes it is useful for user-space to be
able to read them.

Signed-off-by: Feng Tang <feng.tang@intel.com>
Signed-off-by: Len Brown <len.brown@intel.com>
diff --git a/Documentation/ABI/testing/sysfs-firmware-sfi b/Documentation/ABI/testing/sysfs-firmware-sfi
new file mode 100644
index 0000000..4be7d44
--- /dev/null
+++ b/Documentation/ABI/testing/sysfs-firmware-sfi
@@ -0,0 +1,15 @@
+What:		/sys/firmware/sfi/tables/
+Date:		May 2010
+Contact:	Len Brown <lenb@kernel.org>
+Description:
+		SFI defines a number of small static memory tables
+		so the kernel can get platform information from firmware.
+
+		The tables are defined in the latest SFI specification:
+		http://simplefirmware.org/documentation
+
+		While the tables are used by the kernel, user-space
+		can observe them this way:
+
+		# cd /sys/firmware/sfi/tables
+		# cat $TABLENAME > $TABLENAME.bin