Re: [PATCH] powerpc/boot/dts: Fix dtc "pciex" warnings

[Christian Lamparter <chunkeey@gmail.com>]

On 2020-06-23 15:03, Michael Ellerman wrote:
> With CONFIG_OF_ALL_DTBS=y, as set by eg. allmodconfig, we see lots of
> warnings about our dts files, such as:
>
>    arch/powerpc/boot/dts/glacier.dts:492.26-532.5:
>    Warning (pci_bridge): /plb/pciex@d00000000: node name is not "pci"
>    or "pcie"
>
> The node name should not particularly matter, it's just a name, and
> AFAICS there's no kernel code that cares whether nodes are *named*
> "pciex" or "pcie". So shutup these warnings by converting to the name
> dtc wants.
>
> As always there's some risk this could break something obscure that
> does rely on the name, in which case we can revert.

Hmm, I noticed this when I was looking up why nobody commented
on my series of adding more devices to the APM82181/bluestone series:

<https://lore.kernel.org/linuxppc-dev/cover.1598124791.git.chunkeey@gmail.com/>
(I'll post a v3 "soonish".)


Unfortunately yes. This patch will break uboot code in Meraki MX60(W) / MX60.

 > https://github.com/riptidewave93/meraki-uboot/blob/mx60w-20180413/board/amcc/bluestone/bluestone.c#L1178

| if (!pci_available()) {
|     fdt_find_and_setprop(blob, "/plb/pciex@d00000000", "status",
|                   "disabled", sizeof("disabled"), 1);
| }


Backstory: There are two version of the Meraki MX60. The MX60
and the MX60W. The difference is that the MX60W has a populated
mini-pcie slot on the PCB for a >W<ireless card.

That said, this is not earth shattering.

(In theory, this can also cause problems for the bluestone and canyonlands
dev boards that have the option to be configured as either dual sata or
pcie+sata.... But this is probably not a problem for customer boards)

OT: Please note that the plb, opb and ebc node paths (/plb/opb/ebc) are
hardcoded too :(. Amending the proper unit-addresses will lead to no-longer
working DTBs as the "ranges" are missing.

Cheers,
Christian
> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
> ---
>
> diff --git a/arch/powerpc/boot/dts/bluestone.dts b/arch/powerpc/boot/dts/bluestone.dts
> index cc965a1816b6..aa1ae94cd776 100644
> --- a/arch/powerpc/boot/dts/bluestone.dts
> +++ b/arch/powerpc/boot/dts/bluestone.dts
> @@ -325,7 +325,7 @@ EMAC0: ethernet@ef600c00 {
>   			};
>   		};
>   
> -		PCIE0: pciex@d00000000 {
> +		PCIE0: pcie@d00000000 {
>   			device_type = "pci";
>   			#interrupt-cells = <1>;
>   			#size-cells = <2>;