Re: [PATCH 12/16] tile/PCI: Factor 'pcibios_setup()' out of tile

[Chris Metcalf <cmetcalf@tilera.com>]

On 6/28/2012 1:30 PM, Myron Stowe wrote:
> On Tue, 2012-06-26 at 09:18 -0400, Chris Metcalf wrote:
>> On 6/25/2012 11:32 PM, Myron Stowe wrote:
>>> The PCI core provides a generic (__weak) 'pcibios_setup()' routine
>>> that can be used by all architectures as a default.  Drop tile's
>>> architecture specific version in favor of that as it does not need to be
>>> over-ridden.
>>>
>>> Signed-off-by: Myron Stowe <myron.stowe@redhat.com>
>>> ---
>>>
>>>  arch/tile/kernel/pci.c |   10 ----------
>>>  1 files changed, 0 insertions(+), 10 deletions(-)
>> [...]
>> In our internal tree we have x86-like support for "pci=off" here.  [...]
>> But perhaps it would make sense
>> to move the support for "pci=off" to common code, since multiple
>> architectures handle this the same way?
> Looking at the tree I only see three of the architectures currently
> using/implementing "pci=off" (four with the 'tile' addition).  Perhaps
> there is a way to avoid such but it seems like adding this to the core
> would require introducing the global variable 'pci_probe' which seems
> like unnecessary pollution?

I'd argue that the core might expose a pci_probing_disabled() function that
returns whether "pci=off" was seen, and modify the other architectures that
already support pci_probe to call that function instead.  It's true that
x86 has a much more elaborate use of pci_probe than the other
architectures, which means x86 would probably want to keep the variable
as-is and just call pci_probing_disabled() to set pci_probe to zero and return.

All that said, I'm not volunteering to make this change, so if it doesn't
seem right to you, I certainly won't insist. :-)

-- 
Chris Metcalf, Tilera Corp.
http://www.tilera.com