[PATCH v3 09/12] arm64: dts: rp1: Add support for RaspberryPi's RP1 device

Andrea della Porta andrea.porta at suse.com
Wed Nov 6 04:28:52 PST 2024


Hi Stan,

On 15:31 Tue 05 Nov     , Andrea della Porta wrote:
> Hi Stan,
> 
> On 15:29 Mon 04 Nov     , Stanimir Varbanov wrote:
> > Hi Andrea,
> >

...

> > shouldn't this be:
> > 
> > 	rp1_clocks: clocks at 18000 {
> > 		reg = <0x00 0x00018000 0x0 0x10038>;
> > 		...
> > 	}
> > 
> > ?
> > 
> > And for other nodes too...
> 
> For that to be @18000 instead of @c040018000, you should also change
> the "ranges" entry in pci-ep-bus node, as follows:
> 
> ranges = <0x00 0x00018000	//This was: 0xc0 0x40000000
>           0x01 0x00 0x00000000
>           0x00 0x00400000>;
> 
> which is of course feasible, but I prefer to use addresses that 
> resemble (at least to some extent) the ones in RP1 docs.
> 
> Many thanks,
> Andrea

Sorry, this should be like this 

ranges = <0x00 0x00000000	//This was: 0xc0 0x40000000
          0x01 0x00 0x00000000
          0x00 0x00400000>;

i.e. the child address in the range should be 0 and not 0x18000.
Anyway you got the point: in theory we can replace that address
with whatever placeholder we want and from a functional perspective,
it will work, as long as you change all the relevant mappings.
After some brainstorming we've decided to choose a simpler scheme
that will resemble more the internal address described in the RP1
reference manual. 0xC040000000 will become 0x40000000.

Many thanks,
Andrea

...



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