[PATCH v2 4/4] powerpc/83xx: Add PCI-E support for all MPC83xx boards with PCI-E

Leon Woestenberg leon.woestenberg at gmail.com
Wed Jan 7 09:33:35 EST 2009


Hello Anton,

On Tue, Jan 6, 2009 at 10:15 PM, Anton Vorontsov
<avorontsov at ru.mvista.com> wrote:
> On Tue, Jan 06, 2009 at 02:38:57PM -0600, Kumar Gala wrote:
>>>> Is u-boot PCIe initialization required for this kernel patch to work?
>>>
>>> Yup.
>>
>> Really?  what for?
>
> Hm. U-Boot should initialize SerDes and PCI-E controller (pcie laws,
> inbound/outbound windows, clocks, etc.)
>
> Though if PCI-E controller wasn't initialized (i.e. board reflashed
> with the community u-boot), Linux just won't probe the pcie controller:
>
> cfg_bar = in_le32(hose->cfg_data + PEX_OUTWIN0_BAR);
> if (!cfg_bar) {
>        /* PCI-E isn't configured. */
>        ret = -ENODEV;
>        goto err1;
> }
>
> Or did I misunderstand the question?
>
You understood correctly, thanks for answering.

So to summarize, we need u-boot to initialize the PCIe controller, in
order for Linux to further take it over.

What u-boot versions/releases do provide this initialization?

I know the u-boot with the board works, but it's incompatible with
recent Linux kernels.

Regards,
-- 
Leon



More information about the Linuxppc-dev mailing list