Re: Linux PowerPC, PPC4xx

On Wed, 2019-10-16 at 15:19 +0200, Carlo Pisani wrote:

hi
I am a student, I represent a group of friends running a couple of
opensource projects(1), and we are lost with this(2) problem.

I wrote here(2) a couple of years ago, we are still working with
kernel
4.11.0 and there is broken support for initializing the PCI.

The PCI initialization of the PPC405GP seems wrong and every
kernel >= 2.6.26 is not able to correctly address the PDC20265

an interesting note is:
kernel 2.6.26 can be compiled with arch=ppc and arch=powerpc

when compiled with arch=ppc the promise PDC20265 chip is correctly
managed; while when compiled with arch=powerpc the PDC20265 is not
correctly managed

any idea? advice? help? suggestion?
a good place to discuss it?

On powermac we have a quirk to force these controllers into native
mode. You can try that.

Look for pmac_pci_fixup_pciata(). You could copy that to
powerpc/pci_32.c along with

DECLARE_PCI_FIXUP_EARLY(PCI_ANY_ID, PCI_ANY_ID, pmac_pci_fixup_pciata);

(maybe rename pmac to ppc) and remove the line that checks for
machine_is(powermac)

Cheers,
Ben.