[RFC} arm architecture board/feature deprecation timeline

[Andrew Lunn]

On Mon, Aug 19, 2024 at 04:12:10PM +0200, Arnd Bergmann wrote:
> Two small additions:
> 
> On Mon, Aug 19, 2024, at 11:17, Arnd Bergmann wrote:
> > On Thu, Aug 15, 2024, at 21:53, jeremy at jeremypeper.com wrote:
> > I expect that the terastation pro2 is going to be fairly easy to
> > convert to DT as there is already support for similar Orion5x
> > machines. In this case I would just remove all the Orion5x board
> > files and you can add a dts file later on. The bit I'm unsure
> > about here is legacy PCI support. I see that the board file enables
> > both PCI and PCIe, but I don't know if both are actually used,
> > or if everything is on PCIe.
> >
> > I have some old patches for separating orion legacy PCI from
> > PCIe support, as only the latter has a modern driver (shared
> > with kirkwood and armadaxp). If you can confirm that the machine
> > actually uses PCI, I can dig those out from my backups.
> 
> I did find this myself later, the machine does use an on-board
> PCI connected SATA controller, which is obviously required to
> make the machine useful.
> 
> Doing a PCI host bridge driver with DT support correctly is
> a lot of work, especially if there is only a single machine
> using it. Since this uses the same drivers/ata/sata-mv.c
> driver as the other orion/kirkwood machines, I wonder if we
> can just pretend that this is a platform device and skip
> all of the PCI probing. I think this only needs a few
> small changes to the sata-mv.c driver, but it does require
> that the PCI bus is left in a known state by the boot loader.

It is a long time since i looked at Orion, so i could be wrong....

As far as i remember, it has a PCI controller and a PCIe
controller. They are slightly different. The PCIe part is i think
simpler to support, it follows the standards better. I _think_ the PCI
controller uses a GPIO for interrupt support, which causes a mess.

If only PCIe is needed, it should not be too hard to make work. I
would try to avoid the PCI controller is possible.

      Andrew