On Fri, Sep 13, 2013 at 01:17:17PM +0200, Gregory CLEMENT wrote:

On 13/09/2013 13:00, Andrew Lunn wrote:

quoted

On Fri, Sep 13, 2013 at 12:06:29PM +0200, Gregory CLEMENT wrote:

quoted

Hello,

This patch set adds the CPU idle support for Armada XP and prepares
the support for Armada 370. This was based on the work of Nadav
Haklai.

Hi Gregory.

Kirkwood has the ability to put the DDR into self refresh mode, which
is used as part of the second level idle mode. Does 370/XP have this?

Indeed there is a self refresh bit on a DDR related register. I thought
this kind of feature is more likely used for suspend to ram.

The kirkwood data sheet suggests it is useful if the CPU is idle for a
few milliseconds. So it sounds like it is a slow transition, but does
seem to save a bit of power. I guess in a NO_HZ system, it would make
sense.

	Andrew