[PATCH 2/3] powerpc: Enable boot_vga sysfs attribute for graphics adapters on Power

[Bjorn Helgaas]

On Sat, Apr 6, 2013 at 2:00 AM, Benjamin Herrenschmidt
<benh at kernel.crashing.org> wrote:
> On Fri, 2013-04-05 at 14:11 -0600, Bjorn Helgaas wrote:
>>
>> I think sparc has the same issue in its own copy of
>> of_create_pci_dev().
>>
>> Of course, both of_create_pci_dev() implementations are basically
>> copies of the generic pci_setup_device() that most arches use.  That's
>> the reason why I wish sparc and powerpc had used config space
>> accessors that hid the OF mangling internally so they could use the
>> generic pci_setup_device() instead of cloning it.
>
> I disagree :-) I want the config space accessors to actually do the
> config space access (it might be necessary for some reasons, if anything
> for diagnostic). Also one of the reasons we create devices that way
> originally iirc, is that on older pre-PCIe setups, we could have cases
> of a bridge showing up at function N > 0 without anything at function
> 0.
>
> We are also not allowed to mess with bridge BARs on old EADS bridges,
> and similar issues where the hypervisor can get upset.
>
> A "filtering" config space code would be a lot messier than just
> creating them like we do.

Yeah, maybe so.  I guess it's just hard for me to let go of ideas
until I've tried myself and failed :)

Anyway, I hope putting a little more into alloc_pci_dev() will resolve
this particular issue.

Bjorn