Re: [PATCH v2 07/15] arm64: dts: allwinner: h5: Add system-control node with SRAM C1

[Paul Kocialkowski <paul.kocialkowski@bootlin.com>]

Hi,

On Wed, 2018-12-05 at 17:45 +0800, Chen-Yu Tsai wrote:
> On Wed, Dec 5, 2018 at 5:25 PM Paul Kocialkowski
> <paul.kocialkowski@bootlin.com> wrote:
> > Add the H5-specific system control node description to its device-tree
> > with support for the SRAM C1 section, that will be used by the video
> > codec node later on.
> > 
> > The CPU-side SRAM address was obtained empirically while the size was
> > taken from the documentation. They may not be entirely accurate.
> > 
> > Signed-off-by: Paul Kocialkowski <paul.kocialkowski@bootlin.com>
> > ---
> >  arch/arm64/boot/dts/allwinner/sun50i-h5.dtsi | 22 ++++++++++++++++++++
> >  1 file changed, 22 insertions(+)
> > 
> > diff --git a/arch/arm64/boot/dts/allwinner/sun50i-h5.dtsi b/arch/arm64/boot/dts/allwinner/sun50i-h5.dtsi
> > index b41dc1aab67d..42bfb560b367 100644
> > --- a/arch/arm64/boot/dts/allwinner/sun50i-h5.dtsi
> > +++ b/arch/arm64/boot/dts/allwinner/sun50i-h5.dtsi
> > @@ -94,6 +94,28 @@
> >         };
> > 
> >         soc {
> > +               system-control@1c00000 {
> > +                       compatible = "allwinner,sun50i-h5-system-control";
> > +                       reg = <0x01c00000 0x1000>;
> > +                       #address-cells = <1>;
> > +                       #size-cells = <1>;
> > +                       ranges;
> > +
> > +                       sram_c1: sram@1d00000 {
> > +                               compatible = "mmio-sram";
> > +                               reg = <0x00018000 0x1c000>;
> 
> 0x1d00000 or 0x18000?

For the H5, I found the VE SRAM area to be mapped to 0x18000 on the CPU
side (when testing with devmem), unlike the A64, H3 and others. I was
rather surprised about this as well!

> > +                               #address-cells = <1>;
> > +                               #size-cells = <1>;
> > +                               ranges = <0 0x00018000 0x1c000>;
> 
> Same here.
> 
> > +
> > +                               ve_sram: sram-section@0 {
> > +                                       compatible = "allwinner,sun50i-h5-sram-c1",
> > +                                                    "allwinner,sun4i-a10-sram-c1";
> > +                                       reg = <0x000000 0x1c000>;
> > +                               };
> > +                       };
> > +               };
> > +
> >                 mali: gpu@1e80000 {
> >                         compatible = "allwinner,sun50i-h5-mali", "arm,mali-450";
> >                         reg = <0x01e80000 0x30000>;
> > --
> > 2.19.2

Cheers,

Paul

-- 
Paul Kocialkowski, Bootlin (formerly Free Electrons)
Embedded Linux and kernel engineering
https://bootlin.com