Purpose: Demonstrate the usage of the new open sourced rbu (Remote BIOS Update) driver for updating BIOS images on Dell servers and desktops. Scope: This document discusses the functionality of the rbu driver only. It does not cover the support needed from aplications to enable the BIOS to update itself with the image downloaded in to the memory. Overview: This driver works with Dell OpenManage or Dell Update Packages for updating the BIOS on Dell servers (starting from servers sold since 1999), desktops and notebooks (starting from those sold in 2005). Please go to http://support.dell.com register and you can find info on OpenManage and Dell Update packages (DUP). Dell_RBU driver supports BIOS update using the monilothic image and packetized image methods. In case of moniolithic the driver allocates a contiguous chunk of physical pages having the BIOS image. In case of packetized the app using the driver breaks the image in to packets of fixed sizes and the driver would place each packet in contiguous physical memory. The driver also maintains a link list of packets for reading them back. If the dell_rbu driver is unloaded all the allocated memory is freed. The rbu driver needs to have an application which will inform the BIOS to enable the update in the next system reboot. The user should not unload the rbu driver after downloading the BIOS image or updating. The driver load creates the following directories under the /sys file system. /sys/class/firmware/dell_rbu/loading /sys/class/firmware/dell_rbu/data /sys/devices/platform/dell_rbu/image_type /sys/devices/platform/dell_rbu/data The driver supports two types of update mechanism; monolithic and packetized. These update mechanism depends upon the BIOS currently running on the system. Most of the Dell systems support a monolithic update where the BIOS image is copied to a single contiguous block of physical memory. In case of packet mechanism the single memory can be broken in smaller chuks of contiguous memory and the BIOS image is scattered in these packets. By default the driver uses monolithic memory for the update type. This can be changed to contiguous during the driver load time by specifying the load parameter image_type=packet. This can also be changed later as below echo packet > /sys/devices/platform/dell_rbu/image_type Do the steps below to download the BIOS image. 1) echo 1 > /sys/class/firmware/dell_rbu/loading 2) cp bios_image.hdr /sys/class/firmware/dell_rbu/data 3) echo 0 > /sys/class/firmware/dell_rbu/loading The /sys/class/firmware/dell_rbu/ entries will remain till the following is done. echo -1 > /sys/class/firmware/dell_rbu/loading Until this step is completed the drivr cannot be unloaded. Also the driver provides /sys/devices/platform/dell_rbu/data readonly file to read back the image downloaded. This is useful in case of packet update mechanism where the above steps 1,2,3 will repeated for every packet. By reading the /sys/devices/platform/dell_rbu/data file all packet data downloaded can be verified in a single file. The packets are arranged in this file one after the other in a FIFO order. NOTE: This driver requires a patch for firmware_class.c which has the addition of request_firmware_nowait_nohotplug function to wortk Also after updating the BIOS image an user mdoe application neeeds to execute code which message the BIOS update request to the BIOS. So on the next reboot the BIOS knows about the new image downloaded and it updates it self. Also don't unload the rbu drive if the image has to be updated.