[RESEND PATCH 2/4] clk: Unprepare the unused prepared slow clocks at late init

Ulf Hansson ulf.hansson at linaro.org
Wed Mar 20 05:33:48 EDT 2013


On 19 March 2013 20:57, Mike Turquette <mturquette at linaro.org> wrote:
> Quoting Ulf Hansson (2013-03-12 12:26:03)
>> From: Ulf Hansson <ulf.hansson at linaro.org>
>>
>> The unused ungated fast clocks are already being disabled from
>> clk_disable_unused at late init. This patch extend this sequence
>> to the slow unused prepared clocks to be unprepared.
>>
>> Unless the optional .is_prepared callback is implemented by a
>> clk_hw the clk_disable_unused sequence will not unprepare any
>> unused clocks, since it will fall back to use the software
>> prepare counter.
>>
>> Signed-off-by: Ulf Hansson <ulf.hansson at linaro.org>
>> Acked-by: Linus Walleij <linus.walleij at linaro.org>
>
> Hi Ulf,
>
> I've taken all of these patches into clk-next.  Thanks for the resend.
>
> I had to fix up this patch due to commit b67bfe0d, "hlist: drop the node
> parameter from iterators".  The merged version is below.  Let me know if
> you have any issues with it.
>
> Regards,
> Mike
>
>
>
> From ae3865ca119ad82afbf003b4eee38533f32bd0fe Mon Sep 17 00:00:00 2001
> From: Ulf Hansson <ulf.hansson at linaro.org>
> Date: Tue, 12 Mar 2013 20:26:03 +0100
> Subject: [PATCH] clk: Unprepare the unused prepared slow clocks at late init
>
> The unused ungated fast clocks are already being disabled from
> clk_disable_unused at late init. This patch extend this sequence
> to the slow unused prepared clocks to be unprepared.
>
> Unless the optional .is_prepared callback is implemented by a
> clk_hw the clk_disable_unused sequence will not unprepare any
> unused clocks, since it will fall back to use the software
> prepare counter.
>
> Signed-off-by: Ulf Hansson <ulf.hansson at linaro.org>
> Acked-by: Linus Walleij <linus.walleij at linaro.org>
> Signed-off-by: Mike Turquette <mturquette at linaro.org>
> [mturquette at linaro.org: fixed hlist accessors per b67bfe0d]
> ---
>  drivers/clk/clk.c |   28 ++++++++++++++++++++++++++++
>  1 file changed, 28 insertions(+)
>
> diff --git a/drivers/clk/clk.c b/drivers/clk/clk.c
> index 7571b50..c0141f3 100644
> --- a/drivers/clk/clk.c
> +++ b/drivers/clk/clk.c
> @@ -336,6 +336,28 @@ static inline int clk_debug_register(struct clk *clk) { return 0; }
>  #endif
>
>  /* caller must hold prepare_lock */
> +static void clk_unprepare_unused_subtree(struct clk *clk)
> +{
> +       struct clk *child;
> +
> +       if (!clk)
> +               return;
> +
> +       hlist_for_each_entry(child, &clk->children, child_node)
> +               clk_unprepare_unused_subtree(child);
> +
> +       if (clk->prepare_count)
> +               return;
> +
> +       if (clk->flags & CLK_IGNORE_UNUSED)
> +               return;
> +
> +       if (__clk_is_prepared(clk))
> +               if (clk->ops->unprepare)
> +                       clk->ops->unprepare(clk->hw);
> +}
> +
> +/* caller must hold prepare_lock */
>  static void clk_disable_unused_subtree(struct clk *clk)
>  {
>         struct clk *child;
> @@ -386,6 +408,12 @@ static int clk_disable_unused(void)
>         hlist_for_each_entry(clk, &clk_orphan_list, child_node)
>                 clk_disable_unused_subtree(clk);
>
> +       hlist_for_each_entry(clk, &clk_root_list, child_node)
> +               clk_unprepare_unused_subtree(clk);
> +
> +       hlist_for_each_entry(clk, &clk_orphan_list, child_node)
> +               clk_unprepare_unused_subtree(clk);
> +
>         mutex_unlock(&prepare_lock);
>
>         return 0;
> --
> 1.7.10.4
>

Thanks Mike, looks good!

Kind regards
Ulf Hansson



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