[PATCH v5 0/3] Support UEFI SPI I/O protocol

[Paul Barker]

On 23/11/2022 17:50, Paul Barker wrote:
> These patches add support for the UEFI SPI I/O protocol defined in the
> UEFI Platform Initialization (PI) Specification, Version 1.7 Errata A
> (April 2020). This allows a UEFI application to interact with devices
> on the SPI bus.
> 
> This support is initially intended to be used to communicate with SPI
> devices from "pre-boot" UEFI applications which perform setup before
> the main OS is loaded. Other use cases may also be supported, however
> this is not intended to be a replacement for UEFI capsule updates.
> 
> The "pre-boot" UEFI application which we are currently developing will
> interact with a Micron Authenta[1] flash device, sending vendor-specific
> commands over the SPI bus to make use of Authenta security features, to
> verify flash integrity and to generate ephemeral keys based on the flash
> contents.
> 
> The code here is self-contained and easy to enable/disable at compile
> time. Compilation testing with am335x_evm_defconfig shows that the size
> of u-boot.img increases by less than 2kB when CONFIG_EFI_SPI_PROTOCOL
> is enabled.
> 
> [1]: https://www.micron.com/-/media/client/global/documents/products/product-flyer/authenta_technology_solutions_brief.pdf
> 
> Changes since v4:
> 
> * Dropped patches which have already been merged.
> 
> * Re-based on top of my other patch series [2] to avoid conflicts in
>   am335x-sancloud-bbe-lite-u-boot.dtsi.
> 
> * Dropped `am335x_evm_defconfig: Enable Micron SPI flash support` as
>   this was moved to my other patch series [3].
> 
> * Reformat code to fit in 80 chars per line where possible.
> 
> * Use efi_install_multiple_protocol_interfaces() instead of
>   efi_create_handle() & efi_add_protocol().
> 
> * Rename dtb properties to start with 'u-boot,'.
> 
> * Move SanCloud BBE Lite dtb changes to
>   am335x-sancloud-bbe-lite-u-boot.dtsi.
> 
> * Convert remaining printf() calls to debug() calls.
> 
> [2]: https://lore.kernel.org/u-boot/20221114124243.3719037-1-paul.barker@sancloud.com/
> [3]: https://lore.kernel.org/u-boot/20221114124243.3719037-7-paul.barker@sancloud.com/
> 
> Changes since v3:
> 
> * Add implementation of spi_set_speed() so we can use this in
>   efi_spi_io_transaction().
> 
> * Rename convert_efi_string() to efi_convert_string() and move to
>   efi_string.c as a common helper function.
> 
> * Call spi_set_speed() instead of manually de-referencing the function
>   pointer in struct dm_spi_ops.
> 
> * Don't call efi_delete_handle() in destroy_efi_spi_peripheral().
> 
> * Use '%pUl' to print guid string.
> 
> * Split efi_selftest changes into a separate patch.
> 
> Changes since v2:
> 
> * Added description to efi_spi_protocol.h.
> 
> * Moved definition of EFI_SPI_CONFIGURATION_GUID to efi_api.h and
>   added it to the list in lib/uuid.c.
> 
> * Fixed UEFI GUID byte order in test.dts and in debug output.
> 
> * Use log_debug() instead of printf() for debug output.
> 
> * Add test cases to confirm that efi_legacy_spi_controller_protocol
>   functions return EFI_UNSUPPORTED (as they are not currently
>   implemented)
> 
> Changes since v1:
> 
> * Skip emulated SPI peripherals. These appear as duplicates within the
>   list of devices on the bus when using the sandbox SPI drivers.
> 
> * Make most printf statements debug only.
> 
> * Add efi_seltest unit test.
> 
> * Do not enable config EFI_SPI_PROTOCOL by default.
> 
> * Mark functions with EFIAPI where necessary.
> 
> * Handle debug_transaction argument to efi_spi_io_transaction().
> 
> * Handle a value of zero for target->max_read_size &
>   target->max_write_size.
> 
> * Probe inactive SPI devices when initializing the EFI SPI protocol to
>   ensure that dev_get_parent_priv() returns valid data and the exported
>   devices are ready to use.
> 
> Paul Barker (3):
>   efi_loader: Add SPI I/O protocol support
>   efi_selftest: Add tests for SPI protocol support
>   arm: dts: am335x-sancloud-bbe-lite: UEFI SPI export
> 
>  MAINTAINERS                                   |   7 +
>  .../dts/am335x-sancloud-bbe-lite-u-boot.dtsi  |  13 +-
>  arch/arm/dts/am335x-sancloud-bbe-lite.dts     |   2 +-
>  arch/sandbox/dts/test.dts                     |  13 +
>  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/efi_selftest/Makefile                     |   1 +
>  lib/efi_selftest/efi_selftest_spi_protocol.c  | 284 +++++++++
>  lib/uuid.c                                    |   4 +
>  15 files changed, 1086 insertions(+), 4 deletions(-)
>  create mode 100644 include/efi_spi_protocol.h
>  create mode 100644 lib/efi_loader/efi_spi_protocol.c
>  create mode 100644 lib/efi_selftest/efi_selftest_spi_protocol.c
> 

Sending a gentle ping on this series... is there any further feedback?
Are there any outstanding issues to resolve?

Thanks,

-- 
Paul Barker
Principal Software Engineer
SanCloud Ltd

e: paul.barker at sancloud.com
w: https://sancloud.com/