Re: [RFC PATCH 1/2] PCI: designware: Add ARM64 PCI support

[Jingoo Han <jg1.han@samsung.com>]

On Monday, April 21, 2014 10:54 AM, Jingoo Han wrote:
> On Thursday, April 17, 2014 3:26 AM, Arnd Bergmann wrote:
> > On Wednesday 16 April 2014 17:57:24 Liviu Dudau wrote:
> > > Jingoo,
> > >
> > > Thanks for taking a stab at trying to convert a host bridge
> > > driver to use the new generic host bridge code.
> > >
> > > I do however have concerns on the direction you took. You have split
> > > your driver in two, depending on whether it was CONFIG_ARM or CONFIG_ARM64,
> > > even if (with my series) it should be no reason why the host bridge
> > > driver should not work on other architectures as well once they are
> > > converted.
> >
> > Right.
> >
> > > Also, some of the functions that you use have identical names but different
> > > signatures depending on what arch you have selected. This is really bad
> > > in my books!

[.....]

> > > What about creating functions that use my series directly if CONFIG_ARM64 is
> > > defined (or any CONFIG_ you want to create for your driver that you select
> > > from CONFIG_ARM64) and otherwise implement the CONFIG_ARM version? That
> > > way your driver will call only one API without any #ifdef and when arm code
> > > gets converted you drop your adaptation functions. Or (better yet), have a
> > > stab at converting bios32 (Rob Herring has already provided some hints on
> > > how to do it for arch/arm).
> 
> To: Liviu Dudau
> 
> Sorry, but I will not implement this.
> At first, you had to think the compatibility with ARM32 PCIe.
> Why do you want other engineers to take this load?

(+cc Rob Herring)

Um, I am looking at Rob Herring's patchset for Versatile PCI. [1]
Then, do you mean the following?

1. Add Rob Herring's patch converting bios32. [2]
2. Reference Rob Herring's patch in order to know how to
    handle "of_create_pci_host_bridge()" directly in ARM32. [3]
3. Use of_create_pci_host_bridge() for the designware PCIe
    driver in ARM32.
4. Also, use of_create_pci_host_bridge() for the designware PCIe
    driver in "ARM64".


[1] http://www.spinics.net/lists/linux-pci/msg30084.html
[2] http://www.spinics.net/lists/linux-pci/msg30083.html
[3] http://www.spinics.net/lists/linux-pci/msg30086.html

Best regards,
Jingoo Han

> 
> >
> > That would of course be best.
> >

[.....]