Re: [PATCH 10/12] of/irq: Make of_msi_map_rid() PCI bus agnostic

[Rob Herring <robh+dt@kernel.org>]

On Thu, May 21, 2020 at 7:00 AM Lorenzo Pieralisi
<lorenzo.pieralisi@arm.com> wrote:
>
> There is nothing PCI bus specific in the of_msi_map_rid()
> implementation other than the requester ID tag for the input
> ID space. Rename requester ID to a more generic ID so that
> the translation code can be used by all busses that require
> input/output ID translations.
>
> Leave a wrapper function of_msi_map_rid() in place to keep
> existing PCI code mapping requester ID syntactically unchanged.
>
> No functional change intended.
>
> Signed-off-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
> Cc: Rob Herring <robh+dt@kernel.org>
> Cc: Marc Zyngier <maz@kernel.org>
> ---
>  drivers/of/irq.c       | 28 ++++++++++++++--------------
>  include/linux/of_irq.h | 14 ++++++++++++--
>  2 files changed, 26 insertions(+), 16 deletions(-)
>
> diff --git a/drivers/of/irq.c b/drivers/of/irq.c
> index 48a40326984f..25d17b8a1a1a 100644
> --- a/drivers/of/irq.c
> +++ b/drivers/of/irq.c
> @@ -576,43 +576,43 @@ void __init of_irq_init(const struct of_device_id *matches)
>         }
>  }
>
> -static u32 __of_msi_map_rid(struct device *dev, struct device_node **np,
> -                           u32 rid_in)
> +static u32 __of_msi_map_id(struct device *dev, struct device_node **np,
> +                           u32 id_in)
>  {
>         struct device *parent_dev;
> -       u32 rid_out = rid_in;
> +       u32 id_out = id_in;
>
>         /*
>          * Walk up the device parent links looking for one with a
>          * "msi-map" property.
>          */
>         for (parent_dev = dev; parent_dev; parent_dev = parent_dev->parent)
> -               if (!of_map_rid(parent_dev->of_node, rid_in, "msi-map",
> -                               "msi-map-mask", np, &rid_out))
> +               if (!of_map_id(parent_dev->of_node, id_in, "msi-map",
> +                               "msi-map-mask", np, &id_out))
>                         break;
> -       return rid_out;
> +       return id_out;
>  }
>
>  /**
> - * of_msi_map_rid - Map a MSI requester ID for a device.
> + * of_msi_map_id - Map a MSI ID for a device.
>   * @dev: device for which the mapping is to be done.
>   * @msi_np: device node of the expected msi controller.
> - * @rid_in: unmapped MSI requester ID for the device.
> + * @id_in: unmapped MSI ID for the device.
>   *
>   * Walk up the device hierarchy looking for devices with a "msi-map"
> - * property.  If found, apply the mapping to @rid_in.
> + * property.  If found, apply the mapping to @id_in.
>   *
> - * Returns the mapped MSI requester ID.
> + * Returns the mapped MSI ID.
>   */
> -u32 of_msi_map_rid(struct device *dev, struct device_node *msi_np, u32 rid_in)
> +u32 of_msi_map_id(struct device *dev, struct device_node *msi_np, u32 id_in)
>  {
> -       return __of_msi_map_rid(dev, &msi_np, rid_in);
> +       return __of_msi_map_id(dev, &msi_np, id_in);
>  }
>
>  /**
>   * of_msi_map_get_device_domain - Use msi-map to find the relevant MSI domain
>   * @dev: device for which the mapping is to be done.
> - * @rid: Requester ID for the device.
> + * @id: Device ID.
>   * @bus_token: Bus token
>   *
>   * Walk up the device hierarchy looking for devices with a "msi-map"
> @@ -625,7 +625,7 @@ struct irq_domain *of_msi_map_get_device_domain(struct device *dev, u32 id,
>  {
>         struct device_node *np = NULL;
>
> -       __of_msi_map_rid(dev, &np, id);
> +       __of_msi_map_id(dev, &np, id);
>         return irq_find_matching_host(np, bus_token);
>  }
>
> diff --git a/include/linux/of_irq.h b/include/linux/of_irq.h
> index 7142a3722758..cf9cb1e545ce 100644
> --- a/include/linux/of_irq.h
> +++ b/include/linux/of_irq.h
> @@ -55,7 +55,12 @@ extern struct irq_domain *of_msi_map_get_device_domain(struct device *dev,
>                                                         u32 id,
>                                                         u32 bus_token);
>  extern void of_msi_configure(struct device *dev, struct device_node *np);
> -u32 of_msi_map_rid(struct device *dev, struct device_node *msi_np, u32 rid_in);
> +u32 of_msi_map_id(struct device *dev, struct device_node *msi_np, u32 id_in);
> +static inline u32 of_msi_map_rid(struct device *dev,
> +                                struct device_node *msi_np, u32 rid_in)
> +{
> +       return of_msi_map_id(dev, msi_np, rid_in);
> +}
>  #else
>  static inline int of_irq_count(struct device_node *dev)
>  {
> @@ -93,10 +98,15 @@ static inline struct irq_domain *of_msi_map_get_device_domain(struct device *dev
>  static inline void of_msi_configure(struct device *dev, struct device_node *np)
>  {
>  }
> +static inline u32 of_msi_map_id(struct device *dev,
> +                                struct device_node *msi_np, u32 id_in)
> +{
> +       return id_in;
> +}
>  static inline u32 of_msi_map_rid(struct device *dev,
>                                  struct device_node *msi_np, u32 rid_in)

Move this out of the ifdef and you only need it declared once.

But again, I think I'd just kill of_msi_map_rid.

>  {
> -       return rid_in;
> +       return of_msi_map_id(dev, msi_np, rid_in);
>  }
>  #endif
>
> --
> 2.26.1
>