[PATCH 11/12] cpuidle: mvebu: Add initial cpu idle support for Armada 370/XP SoC
khilman at linaro.org
Mon Aug 26 23:28:01 EDT 2013
Gregory CLEMENT <gregory.clement at free-electrons.com> writes:
> Add wfi/cpu idle/cpu deep idle power states support for Armada XP SoC.
> All the latencies and the power consumption values used at the
> "armada_370_xp_idle_driver" structure are preliminary and will be
> modified in the future after running some measurements and analysis.
> Based on the work of Nadav Haklai.
> Signed-off-by: Nadav Haklai <nadavh at marvell.com>
> Signed-off-by: Gregory CLEMENT <gregory.clement at free-electrons.com>
> +int pm_support = WFI;
> +static int __init pm_enable_setup(char *str)
> + if (!strncmp(str, "wfi", 3))
> + pm_support = WFI;
> + else if (!strncmp(str, "idle", 4))
> + pm_support = MV_CPU_IDLE;
> + else if (!strncmp(str, "deepidle", 6))
> + pm_support = MV_CPU_DEEP_IDLE;
> + else if (!strncmp(str, "off", 3))
> + pm_support = DISABLED;
> + return 1;
> +__setup("pm_level=", pm_enable_setup);
Why is this new (but undocumented) kernel commandline needed when there
is already a way to configure the deepest C state from userspace?
(c.f. the 'disable' file under /sys/devices/system/cpu/cpuX/cpuidle/stateY)
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