linux-kernel - Re: [PATCH RFC 0/2] clk: meson: g12a: handle clock hw changes while in suspend

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: <7htv8ykcpm.fsf@baylibre.com>
Date:   Thu, 26 Sep 2019 13:46:29 -0700
From:   Kevin Hilman <khilman@...libre.com>
To:     Neil Armstrong <narmstrong@...libre.com>, sboyd@...nel.org,
        jbrunet@...libre.com, mturquette@...libre.com
Cc:     linux-amlogic@...ts.infradead.org, linux-kernel@...r.kernel.org,
        linux-clk@...r.kernel.org, linux-arm-kernel@...ts.infradead.org,
        Neil Armstrong <narmstrong@...libre.com>
Subject: Re: [PATCH RFC 0/2] clk: meson: g12a: handle clock hw changes while in suspend

Neil Armstrong <narmstrong@...libre.com> writes:

> This serie aime to support when the suspend/resume firmware alters the
> clock tree, leading to an incorrect representation of the clock tree
> after a resume from suspend-to-mem.
>
> For the Amlogic G12A/G12B/SM1 case, the SCPI firmware handling suspend
> alters the CPU clock tree in various ways.
>
> Since we know which part of the tree is possibly altered, we introduce here
> the clk_invalidate_rate() function that will rebuild the tree from the
> hardware registers in case parents and dividers have changed.
>
> Finally we call clk_invalidate_rate() from a new resume callback to refresh
> the CPU clock tree after a resume.
>
> With the clock tree refreshed, CCF can now handle the new clock tree
> configuration and avoid crashing the system on further DVFS set_rates.

For clarification, does this series work without the other proposed
fixes[1]?  or is this dependent on that?

Kevin

[1] https://lore.kernel.org/linux-amlogic/20190919093627.21245-1-narmstrong@baylibre.com/