Re: [PATCH v2 03/11] xen/arm: Introduce pci_find_host_bridge_node helper

[Stefano Stabellini <sstabellini@kernel.org>]

On Thu, 23 Sep 2021, Oleksandr Andrushchenko wrote:
> From: Oleksandr Andrushchenko <oleksandr_andrushchenko@epam.com>
> 
> Get host bridge node given a PCI device attached to it.
> 
> This helper will be re-used for adding PCI devices by the subsequent
> patches.
> 
> Signed-off-by: Oleksandr Andrushchenko <oleksandr_andrushchenko@epam.com>
> Signed-off-by: Oleksandr Tyshchenko <oleksandr_tyshchenko@epam.com>

Reviewed-by: Stefano Stabellini <sstabellini@kernel.org>


> ---
>  xen/arch/arm/pci/pci-host-common.c | 17 +++++++++++++++++
>  xen/include/asm-arm/pci.h          |  1 +
>  2 files changed, 18 insertions(+)
> 
> diff --git a/xen/arch/arm/pci/pci-host-common.c b/xen/arch/arm/pci/pci-host-common.c
> index a88f20175ea9..1567b6e2956c 100644
> --- a/xen/arch/arm/pci/pci-host-common.c
> +++ b/xen/arch/arm/pci/pci-host-common.c
> @@ -283,6 +283,23 @@ int pci_get_host_bridge_segment(const struct dt_device_node *node,
>      return -EINVAL;
>  }
>  
> +/*
> + * Get host bridge node given a device attached to it.
> + */
> +struct dt_device_node *pci_find_host_bridge_node(struct device *dev)
> +{
> +    struct pci_host_bridge *bridge;
> +    struct pci_dev *pdev = dev_to_pci(dev);
> +
> +    bridge = pci_find_host_bridge(pdev->seg, pdev->bus);
> +    if ( unlikely(!bridge) )
> +    {
> +        printk(XENLOG_ERR "Unable to find PCI bridge for "PRI_pci"\n",
> +               pdev->seg, pdev->bus, pdev->sbdf.dev, pdev->sbdf.fn);
> +        return NULL;
> +    }
> +    return bridge->dt_node;
> +}
>  /*
>   * Local variables:
>   * mode: C
> diff --git a/xen/include/asm-arm/pci.h b/xen/include/asm-arm/pci.h
> index 9e366ae67e83..5b100556225e 100644
> --- a/xen/include/asm-arm/pci.h
> +++ b/xen/include/asm-arm/pci.h
> @@ -103,6 +103,7 @@ void __iomem *pci_ecam_map_bus(struct pci_host_bridge *bridge,
>  struct pci_host_bridge *pci_find_host_bridge(uint16_t segment, uint8_t bus);
>  int pci_get_host_bridge_segment(const struct dt_device_node *node,
>                                  uint16_t *segment);
> +struct dt_device_node *pci_find_host_bridge_node(struct device *dev);
>  
>  static always_inline bool is_pci_passthrough_enabled(void)
>  {
> -- 
> 2.25.1
>