Re: [PATCH v9 0/3] PCI: dwc: Enables MSI-X driver support

[Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>]

[+cc Shawn, Vignesh, Pratyush]
On Wed, Feb 28, 2018 at 04:10:22PM +0000, Gustavo Pimentel wrote:
> Changes into a new IRQ handler mechanism (multiplexed IRQ domain hierarchy)
> more suitable and appropriate to use on pcie-designware and on each SoC
> specific driver in order to allow new and more complex features like MSI-X.
> 
> Adds Synopsys Root Complex driver support for MSI-X feature.
> 
> Expands the maximum number of IRQs from 32 to 256 distributed by
> a maximum of 8 controller registers.
> 
> The patch set was made against the Bjorn's master branch (v4.16-rc1).
> 
> Gustavo Pimentel (3):
>   PCI: dwc: Add new IRQ API
>   PCI: dwc: Remove old IRQ API
>   PCI: dwc: Expand maximum number of IRQs from 32 to 256
> 
>  drivers/pci/dwc/pci-exynos.c           |  18 --
>  drivers/pci/dwc/pci-imx6.c             |  18 --
>  drivers/pci/dwc/pci-keystone-dw.c      |  91 +-------
>  drivers/pci/dwc/pci-keystone.c         |   1 +
>  drivers/pci/dwc/pci-keystone.h         |   4 +-
>  drivers/pci/dwc/pci-layerscape.c       |   3 +-
>  drivers/pci/dwc/pcie-artpec6.c         |  18 --
>  drivers/pci/dwc/pcie-designware-host.c | 398 +++++++++++++++++++--------------

Hi Gustavo,

I was reviewing a patch and this raised a question:

-  why pcie-histb.c is not in the list of converted drivers above,
   given that it uses dw_handle_msi_irq() the same way as others
   you converted ?

Is it correct to leave pcie-histb.c as-is ? I do not think it is.

I also would like to get this tested on DRA7 and SPEAR13XX which
are the other host drivers using dw_handle_msi_irq() (even though
in a different way than pcie-histb.c).

The difference here seems to be struct pcie_port->msi_irq usage, that's
extremely confusing how it is used (or not used) in the drivers I
mentioned above.

I have CC'ed the related maintainers I need feedback and this needs
testing; this series code is in my branch:

pci/dwc-msi

Thanks,
Lorenzo

>  drivers/pci/dwc/pcie-designware-plat.c |  16 --
>  drivers/pci/dwc/pcie-designware.h      |  30 ++-
>  drivers/pci/dwc/pcie-qcom.c            |  16 --
>  11 files changed, 258 insertions(+), 355 deletions(-)
> 
> -- 
> 2.7.4
> 
>