Re: [PATCH v4 pci 0/2] PCI/MSI: pci-xgene-msi: Enable MSI support in ACPI boot for X-Gene v1

[Lorenzo Pieralisi]

Hi Khuong,

On Mon, Oct 16, 2017 at 02:19:50PM -0700, Khuong Dinh wrote:
> Hi Lorenzo,
>   Do you have any comments for this patch?

I'd have some comments but given that there are related issues with ACPI
probe ordering that Marc is trying to solve on his side - I will work
with him to see if we can accommodate changes that can solve this issue
too.

Again - I recognize it is a complex problem (that is not even
contemplated by the current ACPI specs), we have to try to make
the solution as generic as we can to prevent reinventing the wheel
anytime a sligthly different issue (related to ACPI probe ordering)
comes up.

Leave it to me (us) and I will get back to you on this.

Thanks,
Lorenzo

> Best regards,
> Khuong Dinh
> 
> On Tue, Sep 26, 2017 at 10:49 AM, Khuong Dinh <kdinh@xxxxxxx> wrote:
> > This patch set enables ACPI MSI support for X-Gene PCIe v1 hardware
> > and provides the proper MSI driver initialization ordering.
> >
> > Signed-off-by: Khuong Dinh <kdinh@xxxxxxx>
> > ---
> > v4:
> >  - Remove Marc Zyngier ACK in v2
> >  - Use acpi_bus_scan on MSI controller handle when MSI device is found
> >  - Register ACPI MSI driver when MSI device is found instead of using
> >  subsys_initcall
> >  - Split ACPI MSI driver support into two patches - one to enable MSI
> > support for X-Gene PCIe v1 hardware, one to enforce MSI driver loaded
> > before PCIe controller driver in ACPI boot mode
> > v3:
> >  - Input X-Gene MSI base address for irq_domain_alloc_fwnode
> >  - Add a hook to enforce X-Gene MSI be probed prior acpi_bus_scan happens
> > v2:
> >  - Verify with BIOS version 3.06.25 and 3.07.09
> > v1:
> >  - Initial version
> > ---
> >
> > Khuong Dinh (2):
> >   PCI/MSI: pci-xgene-msi: Enable MSI support in ACPI boot for X-Gene v1
> >   PCI/MSI: Enforce MSI driver loaded before PCIe in ACPI boot
> >
> >  drivers/acpi/Makefile            |    2 +-
> >  drivers/acpi/acpi_msi.c          |   86 ++++++++++++++++++++++++++++++++++++++
> >  drivers/acpi/acpi_platform.c     |    3 +-
> >  drivers/acpi/internal.h          |    1 +
> >  drivers/acpi/scan.c              |    1 +
> >  drivers/pci/host/pci-xgene-msi.c |   60 ++++++++++++++++++++++++--
> >  include/linux/acpi_msi.h         |   37 ++++++++++++++++
> >  7 files changed, 183 insertions(+), 7 deletions(-)
> >  create mode 100644 drivers/acpi/acpi_msi.c
> >  create mode 100644 include/linux/acpi_msi.h
> >