Re: [PATCH v2] PCI/MSI: Enable PCI_MSI_IRQ_DOMAIN support for Microblaze

[Palmer Dabbelt]

On Mon, 14 Oct 2019 22:59:07 PDT (-0700), michal.simek@xxxxxxxxxx wrote:
> Hi Bjorn,
>
> On 15. 10. 19 1:23, Bjorn Helgaas wrote:
> > On Tue, Oct 08, 2019 at 08:46:52AM -0700, Christoph Hellwig wrote:
> > > > diff --git a/drivers/pci/Kconfig b/drivers/pci/Kconfig
> > > > index a304f5ea11b9..9d259372fbfd 100644
> > > > --- a/drivers/pci/Kconfig
> > > > +++ b/drivers/pci/Kconfig
> > > > @@ -52,7 +52,7 @@ config PCI_MSI
> > > >  	   If you don't know what to do here, say Y.
> > > >
> > > >  config PCI_MSI_IRQ_DOMAIN
> > > > -	def_bool ARC || ARM || ARM64 || X86 || RISCV
> > > > +	def_bool ARC || ARM || ARM64 || X86 || RISCV || MICROBLAZE
> > >
> > > Can you find out what the actual dependency is so that we can
> > > automatically enabled this instead of the weird arch list?
> >
> > Hi Michal, I'll wait for your response on whether it's feasible to do
> > something smarter than listing every arch here.  Please ping here or
> > post a v3; since I marked this patch "Changed Requested" in patchwork,
> > it's fallen off my to-do list.
>
> I was waiting more for you to comment this. I was expecting that the
> same question came last time when RISCV was added.
> I am happy to investigate more about it but definitely some your input
> would help.

Sorry: we usually try to do things the right way but it looks like this got 
lost in the shuffle.  It really doesn't look like there's any 
architecture-specific code implementation on our end:

   commit 251a44888183003b0380df184835a2c00bfa39d7
   Author: Wesley Terpstra <wesley@xxxxxxxxxx>
   Date:   Mon May 20 10:29:26 2019 -0700
   
       riscv: include generic support for MSI irqdomains
   
       Some RISC-V systems include PCIe host controllers that support PCIe
       message-signaled interrupts.  For this to work on Linux, we need to
       enable PCI_MSI_IRQ_DOMAIN and define struct msi_alloc_info.  Support
       for the latter is enabled by including the architecture-generic msi.h
       include.
   
       Signed-off-by: Wesley Terpstra <wesley@xxxxxxxxxx>
       [paul.walmsley@xxxxxxxxxx: split initial patch into one arch/riscv
        patch and one drivers/pci patch]
       Signed-off-by: Paul Walmsley <paul.walmsley@xxxxxxxxxx>
   
   diff --git a/arch/riscv/include/asm/Kbuild b/arch/riscv/include/asm/Kbuild
   index 1efaeddf1e4b..16970f246860 100644
   --- a/arch/riscv/include/asm/Kbuild
   +++ b/arch/riscv/include/asm/Kbuild
   @@ -22,6 +22,7 @@ generic-y += kvm_para.h
    generic-y += local.h
    generic-y += local64.h
    generic-y += mm-arch-hooks.h
   +generic-y += msi.h
    generic-y += percpu.h
    generic-y += preempt.h
    generic-y += sections.h

I bet that dropping the architectures and adding msi.h everywhere it's not 
listed will at least get this building.  I'll give

   diff --git a/drivers/pci/Kconfig b/drivers/pci/Kconfig
   index a304f5ea11b9..77c1428cd945 100644
   --- a/drivers/pci/Kconfig
   +++ b/drivers/pci/Kconfig
   @@ -52,7 +52,7 @@ config PCI_MSI
              If you don't know what to do here, say Y.
   
    config PCI_MSI_IRQ_DOMAIN
   -       def_bool ARC || ARM || ARM64 || X86 || RISCV
   +       def_bool y
           depends on PCI_MSI
           select GENERIC_MSI_IRQ_DOMAIN
   
a build everywhere to see what falls out.