Re: [PATCH RESEND 1/3] PCI: Add fwnode_handle to pci_sysdata

[Bjorn Helgaas <helgaas@kernel.org>]

Hi Jake,

On Tue, Feb 02, 2016 at 05:41:41PM +0000, jakeo@microsoft.com wrote:
> From: Jake Oshins <jakeo@microsoft.com>
> 
> This patch adds an fwnode_handle to struct pci_sysdata, which is
> used by the next patch in the series when trying to locate an
> IRQ domain associated with a root PCI bus.
> 
> Signed-off-by: Jake Oshins <jakeo@microsoft.com>
> ---
>  arch/x86/include/asm/pci.h | 15 +++++++++++++++
>  drivers/pci/probe.c        |  1 +
>  include/linux/pci.h        |  4 ++++
>  3 files changed, 20 insertions(+)
> 
> diff --git a/arch/x86/include/asm/pci.h b/arch/x86/include/asm/pci.h
> index 4625943..6fc3c7c 100644
> --- a/arch/x86/include/asm/pci.h
> +++ b/arch/x86/include/asm/pci.h
> @@ -20,6 +20,9 @@ struct pci_sysdata {
>  #ifdef CONFIG_X86_64
>  	void		*iommu;		/* IOMMU private data */
>  #endif
> +#ifdef CONFIG_PCI_MSI_IRQ_DOMAIN
> +	void		*fwnode;	/* IRQ domain for MSI assignment */
> +#endif
>  };
>  
>  extern int pci_routeirq;
> @@ -32,6 +35,7 @@ extern int noioapicreroute;
>  static inline int pci_domain_nr(struct pci_bus *bus)
>  {
>  	struct pci_sysdata *sd = bus->sysdata;
> +
>  	return sd->domain;
>  }
>  
> @@ -41,6 +45,17 @@ static inline int pci_proc_domain(struct pci_bus *bus)
>  }
>  #endif
>  
> +#ifdef CONFIG_PCI_MSI_IRQ_DOMAIN
> +static inline void *_pci_root_bus_fwnode(struct pci_bus *bus)
> +{
> +	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
>     already-configured bus numbers - to be used for buggy BIOSes
>     or architectures with incomplete PCI setup by the loader */
> diff --git a/drivers/pci/probe.c b/drivers/pci/probe.c
> index 6d7ab9b..b207e74 100644
> --- a/drivers/pci/probe.c
> +++ b/drivers/pci/probe.c
> @@ -15,6 +15,7 @@
>  #include <linux/pci-aspm.h>
>  #include <linux/aer.h>
>  #include <linux/acpi.h>
> +#include <linux/irqdomain.h>

You're not adding a use of anything in irqdomain.h.  It looks like
this hunk should be moved to the second patch.

>  #include <asm-generic/pci-bridge.h>
>  #include "pci.h"
>  
> diff --git a/include/linux/pci.h b/include/linux/pci.h
> index 27df4a6..cd05a8e 100644
> --- a/include/linux/pci.h
> +++ b/include/linux/pci.h
> @@ -1515,6 +1515,10 @@ static inline int pci_get_new_domain_nr(void) { return -ENOSYS; }
>  
>  #include <asm/pci.h>
>  
> +#ifndef pci_root_bus_fwnode
> +#define pci_root_bus_fwnode(bus)	((void)(bus), NULL)

Huh, interesting.  This is new for me; I guess the idea is that we at
least evaluate "bus" even when pci_root_bus_fwnode isn't defined, so
the compiler can catch egregious errors?

> +#endif
> +
>  /* these helpers provide future and backwards compatibility
>   * for accessing popular PCI BAR info */
>  #define pci_resource_start(dev, bar)	((dev)->resource[(bar)].start)
> -- 
> 1.9.1
>