[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]
Message-Id: <20220518205754.8A187C385A5@smtp.kernel.org>
Date: Wed, 18 May 2022 13:57:52 -0700
From: Stephen Boyd <sboyd@...nel.org>
To: Aidan MacDonald <aidanmacdonald.0x0@...il.com>,
mturquette@...libre.com, tsbogend@...ha.franken.de
Cc: paulburton@...nel.org, paul@...pouillou.net,
linux-mips@...r.kernel.org, linux-kernel@...r.kernel.org,
linux-clk@...r.kernel.org
Subject: Re: [PATCH v2 2/3] clk: ingenic: Mark critical clocks in Ingenic SoCs
Quoting Aidan MacDonald (2022-04-28 09:44:53)
> Consider CPU, L2 cache, and memory clocks as critical to prevent
> them -- and the parent clocks -- from being automatically gated,
> since nothing calls clk_get() on these clocks.
>
> Gating the CPU clock hangs the processor, and gating memory makes
> external DRAM inaccessible. Normal kernel code can't hope to deal
> with either situation so those clocks have to be critical.
>
> The L2 cache is required only if caches are running, and could be
> gated if the kernel takes care to flush and disable caches before
> gating the clock. There's no mechanism to do this, and probably no
> reason to do it, so it's simpler to mark the L2 cache as critical.
>
> Signed-off-by: Aidan MacDonald <aidanmacdonald.0x0@...il.com>
> Reviewed-by: Paul Cercueil <paul@...pouillou.net>
> ---
Applied to clk-next
Powered by blists - more mailing lists