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+What:           /sys/firmware/gsmi
+Date:           March 2011
+Contact:        Mike Waychison <mikew@google.com>
+Description:
+                Some servers used internally at Google have firmware
+                that provides callback functionality via explicit SMI
+                triggers.  Some of the callbacks are similar to those
+                provided by the EFI runtime services page, but due to
+                historical reasons this different entry-point has been
+                used.
+
+                The gsmi driver implements the kernel's abstraction for
+                these firmware callbacks.  Currently, this functionality
+                is limited to handling the system event log and getting
+                access to EFI-style variables stored in nvram.
+
+                Layout:
+
+                /sys/firmware/gsmi/vars:
+
+                        This directory has the same layout (and
+                        underlying implementation as /sys/firmware/efi/vars.
+                        See Documentation/ABI/*/sysfs-firmware-efi-vars
+                        for more information on how to interact with
+                        this structure.
+
+                /sys/firmware/gsmi/append_to_eventlog - write-only:
+
+                        This file takes a binary blob and passes it onto
+                        the firmware to be timestamped and appended to
+                        the system eventlog.  The binary format is
+                        interpreted by the firmware and may change from
+                        platform to platform.  The only kernel-enforced
+                        requirement is that the blob be prefixed with a
+                        32bit host-endian type used as part of the
+                        firmware call.
+
+                /sys/firmware/gsmi/clear_config - write-only:
+
+                        Writing any value to this file will cause the
+                        entire firmware configuration to be reset to
+                        "factory defaults".  Callers should assume that
+                        a reboot is required for the configuration to be
+                        cleared.
+
+                /sys/firmware/gsmi/clear_eventlog - write-only:
+
+                        This file is used to clear out a portion/the
+                        whole of the system event log.  Values written
+                        should be values between 1 and 100 inclusive (in
+                        ASCII) representing the fraction of the log to
+                        clear.  Not all platforms support fractional
+                        clearing though, and this writes to this file
+                        will error out if the firmware doesn't like your
+                        submitted fraction.
+
+                        Callers should assume that a reboot is needed
+                        for this operation to complete.