[PATCH v3] clk: exynos7: Keep aclk_fsys1_200 enabled

Sylwester Nawrocki snawrocki at kernel.org
Mon Feb 1 10:18:36 EST 2021


On 1/31/21 18:04, Paweł Chmiel wrote:
> This clock must be always enabled to allow access to any registers in
> fsys1 CMU. Until proper solution based on runtime PM is applied
> (similar to what was done for Exynos5433), fix this by calling
> clk_prepare_enable() directly from clock provider driver.
> 
> It was observed on Samsung Galaxy S6 device (based on Exynos7420), where
> UFS module is probed before pmic used to power that device.
> In this case defer probe was happening and that clock was disabled by
> UFS driver, causing whole boot to hang on next CMU access.
> 
> Signed-off-by: Paweł Chmiel <pawel.mikolaj.chmiel at gmail.com>
> ---
> Changes from v2:
>    - Avoid __clk_lookup() call when enabling clock
> Changes from v1:
>    - Instead of marking clock as critical, enable it manually in driver.

Acked-by: Sylwester Nawrocki <s.nawrocki at samsung.com>



More information about the linux-arm-kernel mailing list