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SubjectRe: [PATCH 1/6] clk: Remove recursion in clk_core_{prepare,enable}()
Quoting Derek Basehore (2018-10-23 18:31:27)
> From: Stephen Boyd <>
> Enabling and preparing clocks can be written quite naturally with
> recursion. We start at some point in the tree and recurse up the
> tree to find the oldest parent clk that needs to be enabled or
> prepared. Then we enable/prepare and return to the caller, going
> back to the clk we started at and enabling/preparing along the
> way.
> The problem is recursion isn't great for kernel code where we
> have a limited stack size. Furthermore, we may be calling this
> code inside clk_set_rate() which also has recursion in it, so
> we're really not looking good if we encounter a tall clk tree.
> Let's create a stack instead by looping over the parent chain and
> collecting clks of interest. Then the enable/prepare becomes as
> simple as iterating over that list and calling enable.
> Cc: Jerome Brunet <>
> Signed-off-by: Stephen Boyd <>
> Signed-off-by: Derek Basehore <>

Did you change anything substantially? Or is it just a resend of my
patch from a while ago? If you can add a link to the original and also
describe what changed in a maintainer tag it would be much easier for me
to compare.

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