On Tue, Jun 22, 2021 at 12:35:17PM +0200, Matthias Brugger wrote:
On 21/06/2021 22:55, Grant Likely wrote:
On 21/06/2021 21:53, Grant Likely wrote: [...]
I've pushed my edited copy out to a temporary branch. You can see it here:
https://github.com/ARM-software/ebbr/commit/9d4632a3911fd460cb1adf6a5b1a2b13...
Correction, here:
https://github.com/ARM-software/ebbr/commit/714f6fd6747f61c0557fdce7d5bed7b5...
Beware that this still has the wording of: "Any platform with hypervisor extension enabled most likely to boot UEFI at HS mode"
I agree that we sould not speculate in EBBR. If we don't know for 100% sure, we should wait until the spec is released. Otherwise confusion will be big.
I think this could be poor drafting of EBBR language rather than an unclear H extension spec.
For Arm platforms we recommend platforms with virtualization support boot the kernel in EL1 but we do not require it since some systems reserved EL1 for additional system firmware (and in one, somewhat notorious case, to deploy Si bug workarounds). I think we would use something similar for RISC-V
I agree entirely EBBR has no business describing what mode if thinks the processor will be in when UEFI starts but that is because it is not relevant rather than because it is speculation. We are in the business of recommending (or requiring) a particular processor mode when we hand over from firmware to the OS. That's what the language here should do.
Daniel.
Regards, Matthias