Re: [PATCH v0] clk: rockchip: Add pclk_rkpwm_pmu to PMU critical clocks in rk3399

[Heiko Stuebner]

Hi Levin,

Am Samstag, 4. August 2018, 09:31:02 CEST schrieb djw@xxxxxxxxxxxxx:
> From: Levin Du <djw@xxxxxxxxxxxxx>
> 
> PWM2 is commonly used to control voltage of PWM regulator of VDD_LOG in
> RK3399. On the Firefly-RK3399 board, PWM2 outputs 40 KHz square wave
> from power on and the VDD_LOG is about 0.9V. When the kernel boots
> normally into the system, the PWM2 keeps outputing PWM signal.
> 
> But the kernel hangs randomly after "Starting kernel ..." line on that
> board. When it happens, PWM2 outputs high level which causes VDD_LOG
> drops to 0.4V below the normal operating voltage.
> 
> By adding "pclk_rkpwm_pmu" to the rk3399_pmucru_critical_clocks array,
> PWM clock is ensured to be prepared at startup and the PWM2 output is
> normal. After repeated tests, the early boot hang is gone.
> 
> This patch works on both Firefly-RK3399 and ROC-RK3399-PC boards.
> 
> Signed-off-by: Levin Du <djw@xxxxxxxxxxxxx>

applied to my clk-branch

Thanks for tracking that down
Heiko