Re: [PATCH v9 0/3] Tango PCIe controller support

Bjorn Helgaas
2017-07-05T18:04:06Z

On Wed, Jul 05, 2017 at 12:55:37AM +0200, Mason wrote:
> On 04/07/2017 22:24, Bjorn Helgaas wrote:
>
> > On Tue, Jun 20, 2017 at 10:12:57AM +0200, Marc Gonzalez wrote:
> >
> >> Marc Z pointed out that posting partial series is not ideal.
> >> Collect last-minute fixups into a single patch series.
> >>
> >> - Bump series to v9 to avoid any ambiguity
> >> - Add Rob's Ack on patch 1
> >>
> >> Marc Gonzalez (3):
> >> PCI: Add DT binding for tango PCIe controller
> >> PCI: Add tango PCIe host bridge support
> >> PCI: Add tango MSI controller support
> >>
> >> .../devicetree/bindings/pci/tango-pcie.txt | 29 ++
> >> drivers/pci/host/Kconfig | 8 +
> >> drivers/pci/host/Makefile | 1 +
> >> drivers/pci/host/pcie-tango.c | 390 +++++++++++++++++++++
> >> include/linux/pci_ids.h | 2 +
> >> 5 files changed, 430 insertions(+)
> >> create mode 100644 Documentation/devicetree/bindings/pci/tango-pcie.txt
> >> create mode 100644 drivers/pci/host/pcie-tango.c
> >
> > I made the trivial changes I mentioned, added a dependency on
> > CONFIG_BROKEN (for the config/MMIO muxing issue), and put these on
> > pci/host-tango. I can't build or test this, so I probably broke
> > something in the process. I think the combination of the boot-time
> > warning, the taint, and CONFIG_BROKEN is a reasonable amount of
> > warning that a user should expect issues.
> >
> > Can you take a look and see if it works for you?
> >
> > https://git.kernel.org/pub/scm/linux/kernel/git/helgaas/pci.git/log/?h=pci/host-tango
>
> Thanks. I'll take it for a spin ASAP.
>
> TAINT_CRAP... Smirk. I didn't see that one in the docs:
> https://www.kernel.org/doc/html/latest/admin-guide/tainted-kernels.html
>
> Oh wait... TAINT_CRAP is "C" => a staging driver has been loaded

I wish it had a less pejorative, more descriptive name. But it seems like
the closest to this situation.

> The one issue I anticipate with "depends on BROKEN" is
> when I add support for revision 2, which isn't broken.

How about this:

- Rename PCIE_TANGO to PCIE_TANGO_REV1
- PCIE_TANGO_REV1 depends on BROKEN
- Add rev2 support later, enabled by PCIE_TANGO
- PCIE_TANGO_REV1 depends on PCIE_TANGO && BROKEN

I updated pci/host-tango along these lines (without rev2 support,
obviously).

I forgot to ask for a MAINTAINERS update. Can you send that, too,
please?

Which reminds me -- are these two addreses

Marc Gonzalez <marc_gonzalez@sigmadesigns.com>
Mason <slash.tmp@free.fr>

different names for the same person? Conversations are easier for me
if I can keep who's who straight :)

Bjorn