RISC-V Platform Spec Review - Canonical

Heinrich Schuchardt

On 9/8/21 6:21 AM, Kumar Sankaran wrote:
Hi Heinrich,
As you know, we have been working on the RISC-V platform spec. At this point, the DRAFT version of the spec is ready for review and is available here https://github.com/riscv/riscv-platform-specs/blob/main/riscv-platform-spec.adoc <https://github.com/riscv/riscv-platform-specs/blob/main/riscv-platform-spec.adoc>
Dear Kumar,

please, see my comments below.

I wanted to request you to do a review of the spec and provide us with all your comments from a Canonical/Ubuntu perspective. Would you be available next week Wed Sep 15^th 9AM PST to go thru a final walk-thru and go over your comments as well?
Yes the time is fine.

Let us know and I will send out a meeting invite. Please let me know who else from Canonical should be involved in the review and do forward this email and the link to the spec to them as well.
I will forward the mail internally.

Thanking you for your help.
Overall the platform specification requires that the reader is quite familiar at least with the ISA specifications. Maybe in a later stage we need a paper that is more accessible for a newcomer.


Please, add EBBR [15] Legacy wired IRQs - DEPRECATED

Please, provide a definition of deprecated in the terminology or the introduction as the usage of this word is RISCV.org specific.

2.1.6. Boot Process

Please, add a reference [15] for EBBR. UEFI

We already require that SBI implements the system reset extension. So
"If SBI SRST implementation is also available, the OS should not use the SBI interface directly but use this UEFI interface."
can be changed to
"The OS shall not use the SBI interface directly but use this UEFI service."
(The UEFI specification uses the word "runtime service".)

2.2. Server Extension

Should we require the implementation of the EFI_TCG2_PROTOCOL (https://trustedcomputinggroup.org/wp-content/uploads/EFI-Protocol-Specification-rev13-160330final.pdf) which is the basis for measured boot? Both EDK II and U-Boot support the protocol if a TPM implementation is available.

Otherwise the specification looks fine to me.

Best regards