[PATCH 2/5] arm: dts: lpc32xx: fix improper usage of ranges property

Arnd Bergmann arnd at arndb.de
Wed Oct 14 07:13:39 PDT 2015


On Wednesday 14 October 2015 17:07:26 Vladimir Zapolskiy wrote:
> On 14.10.2015 16:52, Arnd Bergmann wrote:
> > On Wednesday 14 October 2015 02:13:49 Vladimir Zapolskiy wrote:
> >> Ok, practically it should work for my purposes, but the change must be
> >> done along with added EMC device node description.
> >>
> >> I'm not so confident that it is correct to add description of static
> >> memory banks to ahb node though, please give me a short confirmation,
> > 
> > The DT should reflect whichever memory ranges are accessible
> > on the bus. I've looked up the memory map in the data sheet, and
> > I think a reasonable representation would be
> > 
> > /ahb {
> >       ranges = <0x20000000 0x20000000 0x10000000>, /* AHB port 5 */
> >                <0x30000000 0x30000000 0x10000000>, /* AHB port 6 */
> >                <0x40000000 0x40000000 0x10000000>, /* AHB port 7 */
> >                <0x80000000 0x80000000 0x40000000>, /* EMC DYCS0/1 */
> >                <0xE0000000 0xE0000000 0x04000000>; /* EMC CS0-3 */
> > 
> >       apb {
> >               ranges = <0x20080000 0x20080000 0x00020000>;
> >       };
> > 
> > };
> 
> A simpler version of this change in /ahb I successfully tested with EMC
> yesterday:
> 
> -               ranges = <0x20000000 0x20000000 0x30000000>;
> +               ranges = <0x20000000 0x20000000 0x30000000
> +                         0xe0000000 0xe0000000 0x04000000>;

Ok, but please write this as

               ranges = <0x20000000 0x20000000 0x30000000>,
                        <0xe0000000 0xe0000000 0x04000000>;

The binary is identical, it's just more structured.

> >> then I'll send a change for inclusion of EMC description -- the one
> >> above excluding clocks and clock-names properties, work on CCF is in
> >> progress.
> > 
> > Ah, very nice! That should get us very close to multiplatform support!
> > I've just tried building lpc32xx without the headers to check for
> > other issues, and ended up with the patch below to get it building.
> > It's clearly wrong, but it highlights a number of issues.
> 
> Sure, I'll review the highlighted problems, thanks.

Thanks!

	Arnd



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