Re: [PATCH V2 2/4] ARM: tegra: pmc: add power on function for secondary CPUs

[Stephen Warren <swarren-3lzwWm7+Weoh9ZMKESR00Q@public.gmane.org>]

On 02/26/2013 07:28 PM, Joseph Lo wrote:
> Adding the power on function for secondary CPUs in PMC driver, this can
> help us to remove legacy powergate driver and add generic power domain
> support later.
> 
> Signed-off-by: Joseph Lo <josephl-DDmLM1+adcrQT0dZR+AlfA@public.gmane.org>
> ---
> V2:
> * Don't use ISS_ERR_VALUE for checking error return code
> * the CPU power on function only available for secondary CPU which means
>   we don't care (cpuid <= 0 || cpuid >= num_possible_cpus())

s/don't care/don't support/, I think.

> diff --git a/arch/arm/mach-tegra/pmc.c b/arch/arm/mach-tegra/pmc.c

> +static int tegra_pmc_powergate_set(int id, bool new_state)

> +	reg = tegra_pmc_readl(PMC_PWRGATE_STATUS);
> +
> +	old_state = (reg >> id) & 1;

You could actually replace those last to lines with:

old_state = tegra_pmc_powergate_is_powered_id();

> +static bool tegra_pmc_powergate_is_powered(int id)
> +{
> +	u32 status;
> +
> +	status = tegra_pmc_readl(PMC_PWRGATE_STATUS) & (1 << id);
> +	return !!status;

That might be simpler as:

return (tegra_pmc_readl(PMC_PWRGATE_STATUS) >> id) & 1;

(i.e. the code that's currently part of tegra_pmc_powergate_set to
calculate old_status)