Re: [PATCH V2 3/4] ARM: OMAP3+: PM: VP: check to ensure VP is idle before forceupdate

[Kevin Hilman <khilman@ti.com>]

Nishanth Menon <nm@ti.com> writes:

> Ideally in the flow of DVFS programming, VP should be in idle state
> (since we disabled it) before entering forceupdate. Ensure that
> this is the case. Not doing this could cause VP statemachine
> to enter invalid states. Use ratelimited warnings to prevent spam
> if VP state machine is stuck.
>
> Cc: Tony Lindgren <tony@atomide.com>
> Cc: Kevin Hilman <khilman@ti.com>
>
> Signed-off-by: Vinay Amancha <vinaykumar@ti.com>
> Signed-off-by: Nishanth Menon <nm@ti.com>
> ---
>  arch/arm/mach-omap2/vp.c |    7 +++++++
>  1 file changed, 7 insertions(+)
>
> diff --git a/arch/arm/mach-omap2/vp.c b/arch/arm/mach-omap2/vp.c
> index 4723879..2a8a085 100644
> --- a/arch/arm/mach-omap2/vp.c
> +++ b/arch/arm/mach-omap2/vp.c
> @@ -163,6 +163,13 @@ int omap_vp_forceupdate_scale(struct voltagedomain *voltdm,
>  	u8 target_vsel, current_vsel;
>  	int ret, timeout = 0;
>  
> +	ret = _vp_wait_for_idle(voltdm, vp);
> +	if (ret) {
> +		pr_warn_ratelimited("%s: vdd_%s idle timedout (v=%ld)\n",

nit: s/idle timedout/VP idle timeout/

Kevin

> +				    __func__, voltdm->name, target_volt);
> +		return ret;
> +	}
> +
>  	ret = omap_vc_pre_scale(voltdm, target_volt, &target_vsel, &current_vsel);
>  	if (ret)
>  		return ret;