linux-kernel - Re: [PATCH v4 0/6] RK3588 and Rock 5B dts additions: thermal, OPP and fan

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-ID: <CABjd4YyuDsWGbSfNyqcW3s=59p8adVf5Js79PYyKFqfyM71dxA@mail.gmail.com>
Date: Tue, 28 May 2024 13:49:14 +0400
From: Alexey Charkov <alchark@...il.com>
To: Rob Herring <robh+dt@...nel.org>, 
	Krzysztof Kozlowski <krzysztof.kozlowski+dt@...aro.org>, Conor Dooley <conor+dt@...nel.org>, 
	Heiko Stuebner <heiko@...ech.de>
Cc: Daniel Lezcano <daniel.lezcano@...aro.org>, Dragan Simic <dsimic@...jaro.org>, 
	Viresh Kumar <viresh.kumar@...aro.org>, Chen-Yu Tsai <wens@...nel.org>, 
	Diederik de Haas <didi.debian@...ow.org>, devicetree@...r.kernel.org, 
	linux-arm-kernel@...ts.infradead.org, linux-rockchip@...ts.infradead.org, 
	linux-kernel@...r.kernel.org
Subject: Re: [PATCH v4 0/6] RK3588 and Rock 5B dts additions: thermal, OPP and fan

On Mon, May 6, 2024 at 1:37 PM Alexey Charkov <alchark@...il.com> wrote:
>
> This enables thermal monitoring and CPU DVFS on RK3588(s), as well as
> active cooling on Radxa Rock 5B via the provided PWM fan.
>
> Some RK3588 boards use separate regulators to supply CPUs and their
> respective memory interfaces, so this is handled by coupling those
> regulators in affected boards' device trees to ensure that their
> voltage is adjusted in step.
>
> This also enables the built-in thermal sensor (TSADC) for all boards
> that don't currently have it enabled, using the default CRU based
> emergency thermal reset. This default configuration only uses on-SoC
> devices and doesn't rely on any external wiring, thus it should work
> for all devices (tested only on Rock 5B though).
>
> The boards that have TSADC_SHUT signal wired to the PMIC reset line
> can choose to override the default reset logic in favour of GPIO
> driven (PMIC assisted) reset, but in my testing it didn't work on
> Radxa Rock 5B - maybe I'm reading the schematic wrong and it doesn't
> support PMIC assisted reset after all.
>
> Fan control on Rock 5B has been split into two intervals: let it spin
> at the minimum cooling state between 55C and 65C, and then accelerate
> if the system crosses the 65C mark - thanks to Dragan for suggesting.
> This lets some cooling setups with beefier heatsinks and/or larger
> fan fins to stay in the quietest non-zero fan state while still
> gaining potential benefits from the airflow it generates, and
> possibly avoiding noisy speeds altogether for some workloads.
>
> OPPs help actually scale CPU frequencies up and down for both cooling
> and performance - tested on Rock 5B under varied loads. I've dropped
> those OPPs that cause frequency reductions without accompanying decrease
> in CPU voltage, as they don't seem to be adding much benefit in day to
> day use, while the kernel log gets a number of "OPP is inefficient" lines.
>
> Note that this submission doesn't touch the SRAM read margin updates or
> the OPP calibration based on silicon quality which the downstream driver
> does and which were mentioned in [1]. It works as it is (also confirmed by
> Sebastian in his follow-up message [2]), and it is stable in my testing on
> Rock 5B, so it sounds better to merge a simple version first and then
> extend when/if required.
>
> [1] https://lore.kernel.org/linux-rockchip/CABjd4YzTL=5S7cS8ACNAYVa730WA3iGd5L_wP1Vn9=f83RCORA@mail.gmail.com/
> [2] https://lore.kernel.org/linux-rockchip/pkyne4g2cln27dcdu3jm7bqdqpmd2kwkbguiolmozntjuiajrb@gvq4nupzna4o/
>
> Signed-off-by: Alexey Charkov <alchark@...il.com>
> ---

Hi Heiko,

Do you think this can be merged for 6.11? Looks like there hasn't been
any new feedback in a while, and it would be good to have frequency
scaling in place for RK3588.

Please let me know if you have any reservations or if we need any
broader discussion.

Thanks a lot,
Alexey