On Fri, Jul 08, 2022 at 10:45:55AM +0100, Paul Barker wrote:
This addition allows UEFI applications running under u-boot to access peripherals on SPI busses. It is based on the UEFI Platform Initialization (PI) Specification, Version 1.7 Errata A (April 2020). Only the core functionality required to discover SPI peripherals and communicate with them is currently implemented. Other functionality such as the legacy SPI controller interface and the ability to update the SPI peripheral object associated with a particular SPI I/O protocol object is currently unimplemented.
Since there are no open source implementations of this protocol to use as an example, educated guesses/hacks have been made in cases where the UEFI PI specification is unclear and these are documented in comments.
This implementation has been tested on the SanCloud BBE Lite and allowed a UEFI test application to successfully communicate with a Micron Authenta flash device connected via the SPI bus.
Signed-off-by: Paul Barker paul.barker@sancloud.com
Thanks for doing this. I'll defer to Heinrich for implementation comments but please for the next round don't enable it by default, enable it on your platform. It's good to add this, but we don't want to grow most platforms in code size for it.