Re: [PATCH v4 3/5] ARM: dts: add GXP Support for fans and SPI

[Hawkins, Nick]

 
> > - ahb@c0000000 {
> > + ahb@80000000 {
> > compatible = "simple-bus";
> > #address-cells = <1>;
> > #size-cells = <1>;
> > - ranges = <0x0 0xc0000000 0x30000000>;
> > + ranges = <0x0 0x80000000 0xf000000>, /* 0x80000000 - 0x8f000000 */
> > + <0x40000000 0xc0000000 0x7fffffff>; /* 0xc0000000 - 0xffffffff */


> I'm a bit confused by the change in the mappings: are you
> sure this all the same ahb bus and not two separate buses?

Yes this is the same bus, however we are not including all of
it as it maps some host registers that we do not want to access
at this time. 

> The comment for the second range looks wrong to me, as
> you define a 2GB (minus one byte) sized mapping but the
> comment only lists a 1GB (including the last byte) mapping.


> I would expect that the original 0x30000000 (including the
> last byte) was correct here.

Yes this was incorrect, I believe it should be:

ranges = <0x0 0x80000000 0xf000000>, /* 0x80000000 - 0x8f000000 */
                <0x40000000 0xc0000000 0x3fffffff>; /* 0xc0000000 - 0xffffffff */

I will create a v5 version of this patchset with just this and the
defconfig for your review.

> > - vic1: interrupt-controller@80f00000 {
> > + vic1: interrupt-controller@f00000 { /* 0x80f00000 */


> This is not the same address as before. I'm also not sure the
> comment is helpful here.

My understanding was that the physical address would be the
0x80000000 from the first range plus the 0xf00000 to be
0x80f00000?

Thank you,

-Nick Hawkins