On 10/29/20 5:34 PM, Al Stone wrote:

# Profiles and Platform Spec Technical Subcommittee (P2TS) Agenda: 2 Nov
# 2020


## Meeting Info: weekly on Mondays (09:00 PST, 16:00 UTC)
Details: https://sites.google.com/a/riscv.org/risc-v-staff/home/tech-groups-cal
Past meetings: https://github.com/riscv/riscv-platform-specs/wiki

## In Process Tasks
* Proposed scope/charter
* https://github.com/riscv/riscv-platform-specs/wiki/Draft-Charter
* Pending review in Software meeting
* Reusing the PSCI spec:
* Conversations started with ARM; allowed reuse and long term
* governance
* Consultation on IP on-going

## Topics
* SBI Reset extension (revisit)
* discussion:
* https://lists.riscv.org/g/tech-unixplatformspec/message/212
* discussion:
* https://lists.riscv.org/g/tech-unixplatformspec/message/226
* overlap of functions and reusability
* no public standards body

Additional discussion at [1]. My objections are particularly motivated
by the RFC implementation of this spec for opensbi which just does

hang:
wfi
j hang

if it doesn't have a more specific implementation of shutdown or
warm/cold reboot. The PSCI specification specifies what should happen to
the system from the callee (M-mode) and caller (S-mode) perspective. I
think it's important to specify this for RISC-V as well, so everyone is
on the same page on what reasonable conforming implementations might
looks like.

I also am not sure whether the distinction between warm and cold resets
is useful. What happens if e.g. two different SBI implementations
decided on different interpretations of what those resets entail? I
think the differences between then should be specified more thoroughly,
or they should be eliminated in favor of a single reset type.

[1] https://github.com/riscv/riscv-sbi-doc/pull/39

* SBI PMU extension (revisit)
* discussion:
* https://lists.riscv.org/g/tech-unixplatformspec/message/197
* See SBI Reset above
* Proposal: Hart Suspend Extension for IDLE (revisit)
* discussion:
* https://lists.riscv.org/g/tech-unixplatformspec/message/274
* This proposal is really part of the SBI reset extension proposal
* Proposal: Introduction to spec (revisit)
* discussion:
* https://lists.riscv.org/g/tech-unixplatformspec/message/290
* Existing SBI PRs:
* update?
* tag release v0.3?
* Update on hypervisor work, recommendations for reuse?

## Open Floor
* Anything?

Please discuss [2] and [3]. Thanks.

[2] https://lists.riscv.org/g/tech-unixplatformspec/message/349
[3] https://lists.riscv.org/g/tech-unixplatformspec/message/354

--Sean