[PATCH 5/9] dts: versatile: add sysregs nodes

Lorenzo Pieralisi lorenzo.pieralisi at arm.com
Fri Jan 9 03:53:37 PST 2015


Cc'ing Pawel since he wrote the sysreg code

On Fri, Jan 09, 2015 at 07:10:36AM +0000, Linus Walleij wrote:
> On Fri, Jan 9, 2015 at 12:53 AM, Rob Herring <robherring2 at gmail.com> wrote:
> > On Thu, Jan 8, 2015 at 1:44 PM, Linus Walleij <linus.walleij at linaro.org> wrote:
> 
> >> On Tue, Dec 30, 2014 at 8:28 PM, Rob Herring <robherring2 at gmail.com> wrote:
> >> compatible = "syscon";
> >
> > maybe? VExpress is missing that then...
> 
> I don't like the way some vexpress stuff has been done I think, just
> not enough reviewing power :(

I think that "syscon" is not meant to be there in the first place and it
was done on purpose for vexpress but I need Pawel to confirm and shed
light on this.

> I've tried to make an as clean separation as possible in the Integrator
> as it has been refactored with a minimum of time pressure and
> I tried to make it as reusable as possible. But it doesn't necessarily
> mean I did the right thing all the time ...
> 
> >>> +                               reg = <0x00000 0x1000>;
> >>> +
> >>> +                               v2m_led_gpios: sys_led at 08 {
> >>> +                                       compatible = "arm,vexpress-sysreg,sys_led";
> >>> +                                       gpio-controller;
> >>> +                                       #gpio-cells = <2>;
> >>> +                               };
> >>
> >> These are not GPIOs. These are LED registers really.
> >
> > A register bit that controls an i/o signal sounds like a GPIO to me.
> 
> Are they described as general purpose in the manual for the
> board?
> 
> In the ARM reference design manuals I've seen these bits are
> described as for one purpose only. I mean you can claim the
> memory RE signal is "a bit that controls an I/O signal" as well,
> but we have to think about the abstraction here.

I will have a look into this.

Thanks,
Lorenzo



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