On 4/6/21 4:34 PM, François Ozog wrote:
Hi
following a mail discussion on trusted-firmware A we will have a discussion on HOBs during this week's Trusted Substrate http://trusted-substrate.orgarchitecture council call https://linaro-org.zoom.us/j/94563644892.
In addition to mail thread, here is a deck https://docs.google.com/presentation/d/1KyqkyqoGXHUynZSI2hRFBoO_P7sFwgUJWhjW-Vm2SNk/edit?usp=sharing I'll use to start things up.
Cheers
FF
Dear François,
as long as TF-A uses HOB structures only internally I am not worried.
But when it comes to the interface to other parts of the firmware we should avoid creating multiple parallel interfaces.
The interface between secure firmware and U-Boot is not ARM specific but also exists on RISC-V. Both on ARM and RISC-V we currently use device-trees to transfer system information. I am missing this on your slide 2 "Overall picture for the discussion".
I cannot see anything stopping TF-A from packaging the information that you want to transfer into the device-tree instead of a EFI_HOB_RESOURCE_DESCRIPTOR.
From the U-Boot side I consider this as the preferred solution.
Best regards
Heinrich