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

Anton Vorontsov avorontsov at ru.mvista.com
Wed Jan 7 10:42:56 EST 2009


On Tue, Jan 06, 2009 at 11:33:35PM +0100, Leon Woestenberg wrote:
> 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?

Only FSL U-Boots so far (i.e. community u-boot + fsl patches).

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

We should fix that (if possible).

-- 
Anton Vorontsov
email: cbouatmailru at gmail.com
irc://irc.freenode.net/bd2



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