Re: [PATCH v6 0/2] riscv_pmu_sbi: add support for PMU variant on T-Head C9xx cores

From: Heiko Stübner
Date: Thu Oct 27 2022 - 15:53:35 EST


Am Donnerstag, 27. Oktober 2022, 07:02:59 CEST schrieb Palmer Dabbelt:
> On Tue, 11 Oct 2022 16:18:39 PDT (-0700), heiko@xxxxxxxxx wrote:
> > The PMU on T-Head C9xx cores is quite similar to the SSCOFPMF extension
> > but not completely identical, so this series
>
> The rest of that sentance got dropped, so I put in
>
> The PMU on T-Head C9xx cores is quite similar to the SSCOFPMF extension
> but not completely identical, so this series adds a T-Head PMU errata
> that handlen the differences.
>
> but LMK if you had a better version, it's still early so I don't mind
> swapping it around.

sounds just fine and sorry for not finishing that sentence on my own.


> b4 also got kind of confused here so I had to merge suff manually.

do you still know what b4 complained about?

My patch workflow is pretty basic (git format-patch + separate
git send-email) so I guess it might be interesting what it was
stumbling on.

Thanks
Heiko


> > changes in v6:
> > - follow Anup's suggestion and hook into the (pending) cpuinfo patch [2]
> > instead of modifying the core sbi_get_* functions
> >
> > changes in v5:
> > - add received Reviews
> > - fix sbi caching wrt. negative values (Drew)
> > - add comment about specific c9xx arch- and imp-ids (Conor)
> >
> > changes in v4:
> > - add new patch to cache sbi mvendor, march and mimp-ids (Atish)
> > - errata dependencies in one line (Conor)
> > - make driver detection conditional on CONFIG_ERRATA_THEAD_PMU too (Atish)
> >
> > changes in v3:
> > - improve commit message (Atish, Conor)
> > - IS_ENABLED and BIT() in errata probe (Conor)
> >
> > The change depends on my cpufeature/t-head errata probe cleanup series [1].
> >
> >
> > changes in v2:
> > - use alternatives for the CSR access
> > - make the irq num selection a bit nicer
> >
> > There is of course a matching opensbi-part whose most recent implementation
> > can be found on [0].
> >
> >
> > [0] https://patchwork.ozlabs.org/project/opensbi/cover/20221004164227.1381825-1-heiko@xxxxxxxxx
> > [1] https://lore.kernel.org/all/20220905111027.2463297-1-heiko@xxxxxxxxx/
> > [2] https://lore.kernel.org/r/20220727043829.151794-1-apatel@xxxxxxxxxxxxxxxx
> >
> > Heiko Stuebner (2):
> > RISC-V: Cache SBI vendor values
> > drivers/perf: riscv_pmu_sbi: add support for PMU variant on T-Head
> > C9xx cores
> >
> > arch/riscv/Kconfig.erratas | 13 +++++++++++
> > arch/riscv/errata/thead/errata.c | 19 ++++++++++++++++
> > arch/riscv/include/asm/errata_list.h | 16 ++++++++++++-
> > arch/riscv/include/asm/sbi.h | 5 ++++
> > arch/riscv/kernel/cpu.c | 30 +++++++++++++++++++++---
> > drivers/perf/riscv_pmu_sbi.c | 34 ++++++++++++++++++++--------
> > 6 files changed, 103 insertions(+), 14 deletions(-)
>