[V16,0/7] PCI: Loongson pci improvements and quirks

This patchset improves Loongson PCI controller driver and resolves some
problems: LS2K/LS7A's PCI config space supports 1/2/4-bytes access, so
the first patch use pci_generic_config_read()/pci_generic_config_write()
for them; the second patch add ACPI init support which will be used by
LoongArch; the third patch improves the mrrs quirk for LS7A chipset; The
fourth patch add a new quirk for LS7A chipset to avoid poweroff/reboot
failure, and the fifth patch add a new quirk for LS7A chipset to fix the
multifunction devices' irq pin mappings.

V1 -> V2:
1, Rework the 4th patch;
2, Improve commit messages;
3, Remove the last patch since there is better solutions.

V2 -> V3:
1, Add more affected device ids for the 4th patch;
2, Improve commit messages to describe root causes.

V3 -> V4:
1, Rework the MRRS quirk patch;
2, Improve commit messages to describe root causes, again.

V4 -> V5:
1, Improve the MRRS quirk patch;
2, Change the order of 2nd and 3rd patch;
3, Improve commit messages to describe root causes, again.

V5 -> V6:
1, Rework the 1st patch;
2, Adjust the order of the series.

V6 -> V7:
1, Use correct pci config access operations;
2, Add ACPI init support for LoongArch;
3, Don't move to quirks.c since the driver has ACPI support;
4, Some other minor improvements.

V7 -> V8:
1, Use CFG1 method for LS2K/LS7A pci config.

V8 -> V9:
1, Use pci_controller_data for the first patch. 

V9 -> V10:
1, Add a patch to avoid LS2K/LS7A access unexisting devices.

V10 -> V11:
1, Rebased on 5.16-rc4.

V11 -> V12:
1, Rebased on 5.17-rc5.

V12 -> V13:
1, Rebased on 5.18-rc2;
2, Some minor improvements (adopt Rob Herring's suggestions).

V13 -> V14:
1, Rebased on 5.18;
2, Split ARM64-specific mcfg_quirks to a separate patch;
3, Refactor "PCI: loongson: Don't access non-existant devices";
4, Refactor "PCI: Add quirk for LS7A to avoid reboot failure";
5, Some other minor improvements (adopt Bjorn's suggestions).

V14 -> V15:
1, Rebased on 5.19-rc4;
2, Refactor "PCI: loongson: Don't access non-existant devices".

V15 -> V16:
1, Rebased on 5.19-rc6;
2, Refactor "PCI: loongson: Add ACPI init support".

Huacai Chen, Tiezhu Yang and Jianmin Lv(6):
 PCI/ACPI: Guard ARM64-specific mcfg_quirks
 PCI: loongson: Use generic 8/16/32-bit config ops on LS2K/LS7A.
 PCI: loongson: Add ACPI init support.
 PCI: loongson: Don't access non-existant devices.
 PCI: loongson: Improve the MRRS quirk for LS7A.
 PCI: Add quirk for LS7A to avoid reboot failure.
 PCI: Add quirk for multifunction devices of LS7A.

Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>
Signed-off-by: Jianmin Lv <lvjianmin@loongson.cn> 
Signed-off-by: Tiezhu Yang <yangtiezhu@loongson.cn>
---
 drivers/acpi/pci_mcfg.c               |  13 ++
 drivers/pci/controller/Kconfig        |   2 +-
 drivers/pci/controller/pci-loongson.c | 233 ++++++++++++++++++++++++++--------
 drivers/pci/pci.c                     |   6 +
 drivers/pci/pcie/portdrv_core.c       |   1 -
 drivers/pci/pcie/portdrv_pci.c        |  20 ++-
 include/linux/pci-ecam.h              |   1 +
 include/linux/pci.h                   |   2 +
 8 files changed, 225 insertions(+), 53 deletions(-)
--
2.27.0

On Thu, Jul 14, 2022 at 08:42:09PM +0800, Huacai Chen wrote:
> This patchset improves Loongson PCI controller driver and resolves some
> problems: LS2K/LS7A's PCI config space supports 1/2/4-bytes access, so
> the first patch use pci_generic_config_read()/pci_generic_config_write()
> for them; the second patch add ACPI init support which will be used by
> LoongArch; the third patch improves the mrrs quirk for LS7A chipset; The
> fourth patch add a new quirk for LS7A chipset to avoid poweroff/reboot
> failure, and the fifth patch add a new quirk for LS7A chipset to fix the
> multifunction devices' irq pin mappings.
> ...

> Huacai Chen, Tiezhu Yang and Jianmin Lv(6):
>  PCI/ACPI: Guard ARM64-specific mcfg_quirks
>  PCI: loongson: Use generic 8/16/32-bit config ops on LS2K/LS7A.
>  PCI: loongson: Add ACPI init support.
>  PCI: loongson: Don't access non-existant devices.
>  PCI: Add quirk for multifunction devices of LS7A.

I applied the above to pci/ctrl/loongson to get them out of the way.

>  PCI: loongson: Improve the MRRS quirk for LS7A.
>  PCI: Add quirk for LS7A to avoid reboot failure.

These touch core code in some sort of ugly ways and I'm still thinking
about them.

Hi, Bjorn,

On Sat, Jul 16, 2022 at 6:18 AM Bjorn Helgaas <helgaas@kernel.org> wrote:
>
> On Thu, Jul 14, 2022 at 08:42:09PM +0800, Huacai Chen wrote:
> > This patchset improves Loongson PCI controller driver and resolves some
> > problems: LS2K/LS7A's PCI config space supports 1/2/4-bytes access, so
> > the first patch use pci_generic_config_read()/pci_generic_config_write()
> > for them; the second patch add ACPI init support which will be used by
> > LoongArch; the third patch improves the mrrs quirk for LS7A chipset; The
> > fourth patch add a new quirk for LS7A chipset to avoid poweroff/reboot
> > failure, and the fifth patch add a new quirk for LS7A chipset to fix the
> > multifunction devices' irq pin mappings.
> > ...
>
> > Huacai Chen, Tiezhu Yang and Jianmin Lv(6):
> >  PCI/ACPI: Guard ARM64-specific mcfg_quirks
> >  PCI: loongson: Use generic 8/16/32-bit config ops on LS2K/LS7A.
> >  PCI: loongson: Add ACPI init support.
> >  PCI: loongson: Don't access non-existant devices.
> >  PCI: Add quirk for multifunction devices of LS7A.
>
> I applied the above to pci/ctrl/loongson to get them out of the way.
Thank you very much!

>
> >  PCI: loongson: Improve the MRRS quirk for LS7A.
> >  PCI: Add quirk for LS7A to avoid reboot failure.
>
> These touch core code in some sort of ugly ways and I'm still thinking
> about them.
Yes, it is ugly, but I hope it can be solved in some way, at least the
MRRS problem is not only Loongson-specific and can be shared by
others.

Huacai