On 05/30/2013 05:20:34 AM, Kevin Hao wrote:

On Tue, May 28, 2013 at 05:52:09PM -0500, Scott Wood wrote:

quoted

On 05/21/2013 07:04:58 AM, Kevin Hao wrote:

quoted

It also seems that we don't support ISA on all the current corenet =20

ds

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boards. So picking a primary bus seems useless, remove that =20

function

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too.

IIRC that was due to some bugs in the PPC PCI code in the absence of
any primary bus.

=20
Do you know more about these bugs?

Not off the top of my head -- either search the archives or ask Ben.

quoted

 fsl_pci_assign_primary() will arbitrarily pick one
to be primary if there's no ISA.  Have the bugs been fixed?

=20
I know there should be some reason that we put the =20
fsl_pci_assign_primary()
here. But frankly I am not sure what bugs this workaround try to fix. =20
For these
corenet boards picking one to be primary has no effect to the 64bit =20
kernel.
And for 32bit kernel, the only effect of this is that isa_io_base is =20
set to the
io virtual base of the primary bus. But the isa_io_base only make =20
sense when
we do have a isa bus, so that we can access some well-known io ports =20
directly
by using outx/inx. But if we don't have isa bus on the board, the =20
value of
isa_io_base should make no sense at all. So we really don't need to =20
pick a
fake primary bus. Of course I may miss something, correct me if I am =20
wrong. :-)

outx/inx can also be used for PCI I/O BARs.

-Scott=