Hi Paul,
On Wed, 23 Nov 2022 at 10:50, Paul Barker paul.barker@sancloud.com 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.
The following protocols are defined:
- EFI_SPI_CONFIGURATION_PROTOCOL
- EFI_SPI_IO_PROTOCOL
- EFI_LEGACY_SPI_CONTROLLER_PROTOCOL
Since there are no open source implementations of these protocols 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
MAINTAINERS | 6 + configs/am335x_evm_defconfig | 1 + include/efi_api.h | 4 + include/efi_loader.h | 4 + include/efi_spi_protocol.h | 166 +++++++++ lib/efi_loader/Kconfig | 8 + lib/efi_loader/Makefile | 1 + lib/efi_loader/efi_setup.c | 6 + lib/efi_loader/efi_spi_protocol.c | 576 ++++++++++++++++++++++++++++++ lib/uuid.c | 4 + 10 files changed, 776 insertions(+) create mode 100644 include/efi_spi_protocol.h create mode 100644 lib/efi_loader/efi_spi_protocol.c
This should have a sandbox test as well. See test/dm/spi.c or sf.c for examples.
Regards, Simon