RE: [PATCH v5 5/7] PCI: irqdomain: Look up IRQ domain by fwnode_handle

[Jake Oshins]

> -----Original Message-----
> From: Andy Shevchenko [mailto:andy.shevchenko@xxxxxxxxx]
> Sent: Friday, October 30, 2015 2:44 PM
> To: Jake Oshins <jakeo@xxxxxxxxxxxxx>
> Cc: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>; KY Srinivasan
> <kys@xxxxxxxxxxxxx>; linux-kernel@xxxxxxxxxxxxxxx;
> devel@xxxxxxxxxxxxxxxxxxxxxx; olaf@xxxxxxxxx; Robo Bot
> <apw@xxxxxxxxxxxxx>; Vitaly Kuznetsov <vkuznets@xxxxxxxxxx>;
> tglx@xxxxxxxxxx; Haiyang Zhang <haiyangz@xxxxxxxxxxxxx>;
> marc.zyngier@xxxxxxx; Bjorn Helgaas <bhelgaas@xxxxxxxxxx>; linux-
> pci@xxxxxxxxxxxxxxx
> Subject: Re: [PATCH v5 5/7] PCI: irqdomain: Look up IRQ domain by
> fwnode_handle
> 
> On Fri, Oct 30, 2015 at 11:11 PM,  <jakeo@xxxxxxxxxxxxx> wrote:
> > From: Jake Oshins <jakeo@xxxxxxxxxxxxx>
> >
> > This patch adds a second way of finding an IRQ domain associated with
> > a root PCI bus.  After looking to see if one can be found through
> > the OF tree, it attempts to look up the IRQ domain through an
> > fwnode_handle stored in the pci_sysdata struct.
> >
> > Signed-off-by: Jake Oshins <jakeo@xxxxxxxxxxxxx>
> > ---
> >  arch/x86/include/asm/pci.h |  4 +++-
> >  drivers/pci/probe.c        | 11 +++++++++++
> >  include/asm-generic/pci.h  |  4 ++++
> >  3 files changed, 18 insertions(+), 1 deletion(-)
> >
> > diff --git a/arch/x86/include/asm/pci.h b/arch/x86/include/asm/pci.h
> > index 10213a1..fb74453 100644
> > --- a/arch/x86/include/asm/pci.h
> > +++ b/arch/x86/include/asm/pci.h
> > @@ -45,11 +45,13 @@ static inline int pci_proc_domain(struct pci_bus
> *bus)
> >  #endif
> >
> >  #ifdef CONFIG_PCI_MSI_IRQ_DOMAIN
> > -static inline void *pci_fwnode(struct pci_bus *bus)
> > +static inline void *_pci_root_bus_fwnode(struct pci_bus *bus)
> 
> I'm sorry what is the point to rename?
> 

I renamed it only because Gerry asked me to rename it.  And then I regenerated the patch series with that rename still in the queue, which was a mistake.  The whole thing is introduced in the previous patch.  pci_fwnode() doesn't exist without this patch series.  I'll straighten that out.


> >  {
> >         struct pci_sysdata *sd = bus->sysdata;
> >         return sd->fwnode;
> >  }
> > +
> > +#define pci_root_bus_fwnode    _pci_root_bus_fwnode
> >  #endif
> >
> >  /* Can be used to override the logic in pci_scan_bus for skipping
> > diff --git a/drivers/pci/probe.c b/drivers/pci/probe.c
> > index f441d1b..60e50a8 100644
> > --- a/drivers/pci/probe.c
> > +++ b/drivers/pci/probe.c
> > @@ -671,6 +671,17 @@ static struct irq_domain
> *pci_host_bridge_msi_domain(struct pci_bus *bus)
> >          */
> >         d = pci_host_bridge_of_msi_domain(bus);
> >
> > +#ifdef CONFIG_PCI_MSI_IRQ_DOMAIN
> > +       /*
> > +        * If no IRQ domain was found via the OF tree, try looking it up
> > +        * directly through the fwnode_handle.
> > +        */
> > +       if (!d && pci_root_bus_fwnode(bus)) {
> > +               d = irq_find_matching_fwnode(pci_root_bus_fwnode(bus),
> > +                                            DOMAIN_BUS_PCI_MSI);
> 
> Gave a second glance and now noticed that you call
> pci_root_bus_fwnode() twice. So, it actually might be more readable
> like your first but modified variant:
> 
> if (!d) {
>   void *fwnode = pci_fwnode(bus);
> 
>   if (fwnode)
>     d = irq_find_matching_fwnode(fwnode, DOMAIN_BUS_PCI_MSI);
> }
> 
> > +       }
> > +#endif
> > +
> >         return d;
> >  }
> 
> 
> With Best Regards,
> Andy Shevchenko

Sure.  No problem.  I'll resend.

-- Jake