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

[Andy Shevchenko]

On Fri, Oct 30, 2015 at 11:11 PM,  <jakeo at microsoft.com> wrote:
> From: Jake Oshins <jakeo at microsoft.com>
>
> 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 at microsoft.com>
> ---
>  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?

>  {
>         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