new efi_capsule_loader Linux kernel interface from Intel

Hock Leong Kweh of Intel posted a patch to the Linux kernel which exposes a new UEFI capsule update interface. Some excerpts from the patch:

efi: a misc char interface for user to update efi firmware

Introducing a kernel module to expose capsule loader interface (misc char device file note) for user to upload capsule binaries. This option exposes a loader interface “/dev/efi_capsule_loader” for user to load EFI capsule binary and update the EFI firmware through system reboot. It expose a misc char interface for user to upload the capsule binary and calling efi_capsule_update() API to pass the binary to EFI firmware. The steps to update efi firmware are:

1) cat firmware.cap > /dev/efi_capsule_loader
2) reboot

Any failed upload error message will be returned while doing “cat” through Write() function call. Tested the code with Intel Quark Galileo platform. This patchset is created on top of Matt’s patchset:
1.) “[PATCH 1/2] efi: Move efi_status_to_err() to efi.h”
2.) “[PATCH 2/2] efi: Capsule update support”

See the linux-kernel/linux-efi/linux-fsdevel list archives for the patch ( is down for me currently, hope it returns…):

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