OF: Can't handle multiple dma-ranges with different offsets

[Chris Packham]

On 22/07/20 4:19 pm, Chris Packham wrote:
> Hi,
>
> I've just fired up linux kernel v5.7 on a p2040 based system and I'm 
> getting the following new warning
>
> OF: Can't handle multiple dma-ranges with different offsets on 
> node(/pcie at ffe202000)
> OF: Can't handle multiple dma-ranges with different offsets on 
> node(/pcie at ffe202000)
>
> The warning itself was added in commit 9d55bebd9816 ("of/address: 
> Support multiple 'dma-ranges' entries") but I gather it's pointing out 
> something about the dts. My boards dts is based heavily on 
> p2041rdb.dts and the relevant pci2 section is identical (reproduced 
> below for reference).
>
>     pci2: pcie at ffe202000 {
>         reg = <0xf 0xfe202000 0 0x1000>;
>         ranges = <0x02000000 0 0xe0000000 0xc 0x40000000 0 0x20000000
>               0x01000000 0 0x00000000 0xf 0xf8020000 0 0x00010000>;
>         pcie at 0 {
>             ranges = <0x02000000 0 0xe0000000
>                   0x02000000 0 0xe0000000
>                   0 0x20000000
>
>                   0x01000000 0 0x00000000
>                   0x01000000 0 0x00000000
>                   0 0x00010000>;
>         };
>     };
>
> I haven't noticed any ill effect (aside from the scary message). I'm 
> not sure if there's something missing in the dts or in the code that 
> checks the ranges. Any guidance would be appreciated.

I've also just checked the T2080RDB on v5.7.9 which shows a similar issue

OF: Can't handle multiple dma-ranges with different offsets on 
node(/pcie at ffe250000)
OF: Can't handle multiple dma-ranges with different offsets on 
node(/pcie at ffe250000)
pcieport 0000:00:00.0: Invalid size 0xfffff9 for dma-range
pcieport 0000:00:00.0: AER: enabled with IRQ 21
OF: Can't handle multiple dma-ranges with different offsets on 
node(/pcie at ffe270000)
OF: Can't handle multiple dma-ranges with different offsets on 
node(/pcie at ffe270000)
pcieport 0001:00:00.0: Invalid size 0xfffff9 for dma-range
pcieport 0001:00:00.0: AER: enabled with IRQ 23