Hi Vincent,
On Mon, Nov 29, 2010 at 3:19 PM, Vincent Guittot vincent.guittot@linaro.org wrote:
This patch extracts the common code of the cpu hotplug feature across arm platforms. The goal is to only keep the specific stuff of the platform in the sub-architecture. I have created a hotplug.c file in the arm/common directory after studying the cpu hotplug code of omap2, realview, s5pv310, ux500 and tegra. I have extracted 3 main platform dependent functions: -platform_enter_lowpower which prepares the platform for low power. -platform_do_lowpower on which the cpu will loop until it becomes really plugged (spurious wake up). This function must returned the cpu Id in order to leave the unplug state. -platform_leave_lowpower which restore the platform context. An ux500 patch is available which uses the common/hotplug.c code. This patch is quite short because the idle / power down functions are not yet upstreamed
I had posted a patch which does exactly the same thing sometime ago, but it got dropped off from the radar. The patch set can be referenced @ http://www.spinics.net/lists/arm-kernel/msg97600.html I remember getting it Acked by most of the platform maintainers, but Russell had some reservations on that.
Cheers!
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