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Date: Fri, 8 Dec 2017 11:02:25 +0000
From: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
To: Joao Pinto <Joao.Pinto@synopsys.com>
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Subject: Re: Re-activate task to add MSI-X to pcie-designware
Message-ID: <20171208110225.GC26816@red-moon>
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On Thu, Dec 07, 2017 at 03:14:22PM +0000, Joao Pinto wrote:
> Hello to all,
> 
> I am sending this e-mail to request your opinion about the tasks needed to add
> support for MSI-X for pcie-designware based solutions.
> 
> A few months ago I submited a patch-set that added support for MSI-X:
> 
> [v2,9/9] pci: remove limitation of the number of the available IRQs
> https://patchwork.ozlabs.org/patch/771320/
> [v2,8/9] pci: removing old irq api from pcie-designware
> https://patchwork.ozlabs.org/patch/771360/
> [v2,7/9] pci: keystone SoC driver adapted to new irq API
> https://patchwork.ozlabs.org/patch/771361/
> [v2,6/9] pci: qcom SoC driver adapted to new irq API
> https://patchwork.ozlabs.org/patch/771362/
> [v2,5/9] pci: generic PCIe DW driver adapted to new irq API
> https://patchwork.ozlabs.org/patch/771365/
> [v2,4/9] pci: artpec6 SoC driver adapted to new irq API
> https://patchwork.ozlabs.org/patch/771364/
> [v2,3/9] pci: imx6 SoC driver adapted to new irq API
> https://patchwork.ozlabs.org/patch/771363/
> [v2,2/9] pci: exynos SoC driver adapted to new irq API
> https://patchwork.ozlabs.org/patch/771359/
> [v2,1/9] pci: adding new irq api to pci-designware
> https://patchwork.ozlabs.org/patch/771366/
> 
> The patch-set was globally accepted, but it broke the MSI mechanism for
> Keystone, due to its specificity.

Hi Joao,

would you mind pointing me at the discussion where the breakage was
explained please ? It is to understand what are the TI specific bits
we are talking about here.

> We are now going to resume this task and we would like to have your feedback
> about our plan:
> 
> Task 1: Help TI to create a keystone_msi driver to isolate its custom msi mechanism
> Task 2: Port the existing patches to the new kernel version (except the keystone
> one)
> 
> If TI can do the keystone_msi implementation it would be easier. If it's not
> possible, we volunteer to do it, but we will need testing & debug assistance.

I would ask Murali to chime in please to understand the direction to
take - at least I expect him to be able to test the changes.

Thanks,
Lorenzo