[PATCH 0/2] Improve CPPC counter scalability via local emulation

[Anup Patel]

On Fri, Jul 3, 2026 at 10:35 AM Sunil V L <sunilvl at oss.qualcomm.com> wrote:
>
> From: Sunil V L <sunilvl at oss.qualcomm.com>
>
> This series improves the scalability of the RPMI-based CPPC driver's
> REFERENCE_CTR and DELIVERED_CTR registers, which are read frequently
> by CPU frequency governors.
>
> Currently, every read of these counters sends an RPMI message to the
> controller. Since REFERENCE_CTR can be just the TIME csr and, when the
> fast channel is supported, DELIVERED_CTR can be derived from the
> current frequency exposed via the fast channel, both can instead be
> emulated locally without a round trip to the controller.
>
> Sunil V L (2):
>   lib/sbi/sbi_timer: Add sbi_timer_frequency() function
>   lib/utils/cppc: Emulate REFERENCE_CTR and DELIVERED_CTR locally

LGTM.

Reviewed-by: Anup Patel <anup at brianfault.org>

Applied this series to the riscv/opensbi repo.

Thanks,
Anup