Firmware Storage : Technical Overview Copyright © Intel Corporation Intel Corporation Software and Services Group

® UEFI / Framework Training 2008 Copyright © Intel Corporation Other trademarks and brands are the property of their respective owners Slide 2 Firmware Storage Platform Initialization Firmware Volume –Basic storage repository for data and code is the FV –Each FV is organized into a file system, each with attributes Firmware File System format –A firmware file system (FFS) describes the organization of files and free space within the firmware volume. –Each firmware file system has a unique GUID, which is used by the firmware to associate a driver with a newly exposed FV Firmware Files –Code and data stored in firmware volumes –Each of the files has the following attributes Name, Type, Alignment, Size See § 2.1 PI 1.1 Vol. 3 Spec

® UEFI / Framework Training 2008 Copyright © Intel Corporation Other trademarks and brands are the property of their respective owners Slide 3 Code/Data Storage Models File System Support for EFI system partition –File system header contains a GUID which describes the format of the firmware file system used to organize the firmware volume data. (i.e. FAT 32) –Pluggable file system abstraction Firmware volumes (FV) –Location and media independence Code and data location need not be determined at build time –Dispatcher and BDS can use FV, File or network to find required components –Can change packaging based on platform needs Framework Code and Data Storage

® UEFI / Framework Training 2008 Copyright © Intel Corporation Other trademarks and brands are the property of their respective owners Slide 4 File System for FLASH Devices FLASH Devices Chipset Resources PCI Devices System Memory 0x xFFFF FFFF (4GB) Boot Firmware Volume Main Firmware Volume File #1 File #2... File #n Section #1 Section #2 Section #1 Section #2 Flexible FLASH Layout Flat File System –Files Named by GUID –Updateable Extensible File Format

® UEFI / Framework Training 2008 Copyright © Intel Corporation Other trademarks and brands are the property of their respective owners Slide 5 Firmware Volume The Firmware Volume is the basic firmware storage abstraction –Read only until read/write DXE driver loads Implemented as layered protocols –Firmware Volume protocol (abstracts formatting of firmware device) –Firmware Volume Block protocol (abstracts firmware device hardware and partitioning) Firmware File System –Space-optimized binary flat format –Architectural for PEI Firmware Volume Driver Firmware Volume Block Driver Firmware Storage Device Low level interface File level interface Storage Definition enables modularity Framework Code and Data Storage

® UEFI / Framework Training 2008 Copyright © Intel Corporation Other trademarks and brands are the property of their respective owners Slide 6 FV Update Goals Generic interface to update mechanism –Common default human interface OEM may supply their own –Self describing and use a common format No more special purpose tools to support, maintain, learn –Ideally just another OS Control Panel applet Scalable integrity framework –Interface should enable a range of mechanisms to prevent viral attack on FVs Framework Code and Data Storage

® UEFI / Framework Training 2008 Copyright © Intel Corporation Other trademarks and brands are the property of their respective owners Slide 7 Capsules Package of data in a known format –Some used by OS Associated revision data, titles and etc. displayed by application –Some used by Firmware New modules Programs Reuse definitions and code from firmware volumes Capsules are a way for the OS to provide DXE drivers to be run at the next reboot –Firmware update is an application of Capsules So is Recovery –Other non-architectural mechanisms to support update and recovery may be provided as value-add Framework Code and Data Storage

® UEFI / Framework Training 2008 Copyright © Intel Corporation Other trademarks and brands are the property of their respective owners Slide 8 Capsule Structure Capsule Capsule Header Header – used by OS present application, not loaded into RAM Capsule volume (“CV”) Image – firmware volume with a different type GUID Firmware Volume (“FV”) file: a firmware volume stored as a single file Security ‘wrapper’ – for example, a digital signature of the contents to be validated while processing the CV “Capsule Payload”: Various files. Can include executable DXE drivers, images, etc. In the case of update, might include both the image to update and the drivers to perform the update Parameter file – file generated by Setup, path data, etc. Capsule Volume Image Firmware Volume File Security Wrapper (optional) Parameter File Capsule Payload Framework Code and Data Storage

® UEFI / Framework Training 2008 Copyright © Intel Corporation Other trademarks and brands are the property of their respective owners Slide 9 From CV to FV 2. Make capsule volume from CV image Capsule Volume Security Wrapper Parameter File Capsule Payload FV File 3. Validate security Capsule Volume Parameter File Capsule Payload FV File 4. Create new RAM Firmware Volume from FV File Capsule Payload Firmware Volume 5. Write non-executable (hence non-viral) param files Capsule Payload Firmware Volume Parameter File The security wrapper is optional. An alternative, which would preserve or even add security, would be to sign each driver. Security requirements are defined by platform policy. At #4, the dispatcher will scan the files in the new FV, discovering drivers to schedule. CV image Security Wrapper Parameter File Capsule Payload 1. Load CV image into RAM FV File Framework Code and Data Storage

® UEFI / Framework Training 2008 Copyright © Intel Corporation Other trademarks and brands are the property of their respective owners Slide 10 Storage Summary Standard storage enables modularity –Drivers don’t need to know about FLASH specifics –Modules from different vendors can co-exist in one FLASH Efficient FLASH utilization Support multiple FLASH devices Modular Fault Tolerant Updates Framework Code and Data Storage

® UEFI / Framework Training 2008 Copyright © Intel Corporation Other trademarks and brands are the property of their respective owners Slide 11 Demo Loading Drivers from non-FLASH locations

® UEFI / Framework Training 2008 Copyright © Intel Corporation Other trademarks and brands are the property of their respective owners Slide 12 Q & A

® UEFI / Framework Training 2008 Copyright © Intel Corporation Other trademarks and brands are the property of their respective owners Slide 13

® UEFI / Framework Training 2008 Copyright © Intel Corporation Other trademarks and brands are the property of their respective owners Slide 14 Back up