[PATCH 1/3] clk: mvebu: add gate ctrl for Prestera kirkwood variants

Andrew Lunn andrew at lunn.ch
Wed May 8 02:32:44 EST 2013


On Tue, May 07, 2013 at 06:11:44PM +0200, Gregory CLEMENT wrote:
> On 05/07/2013 05:52 PM, Valentin Longchamp wrote:
> > The kirkwood device found in the Prestera SoCs does not have all the
> > peripherals of its the usual kirkwood SoCs. There are hence missing
> > clocks in the SoCs.
> > 
> > This patch registers another gate controller for the kirkwood that
> > registers only the available clocks of this kirkwood variant.
> 
> Hi Valentin,
> 
> Overall the patch set looks OK, however I don't understand why you need
> to declare a new gate controller. The list you delcared seemed to be
> just a subset of the Kirkwood one, why can't you use this one?

Hi Gregory

Take a look at the code which gets deleted in patch 3/3.

       /*
        * Our variant of kirkwood (integrated in the Bobcat) hangs on accessing
        * SATA bits (14-15) of the Clock Gating Control Register. Since these
        * devices are also not present in this variant, their clocks get
        * disabled because unused when clk_disable_unused() gets called.
        * That's why we change the flags to these clocks to CLK_IGNORE_UNUSED
        */

By not defining these clocks in the first place, they never get turned
off...

	Andrew


More information about the devicetree-discuss mailing list