Re: [PATCH v4 03/11] xen/arm: Introduce pci_find_host_bridge_node helper

[Rahul Singh <Rahul.Singh@arm.com>]

Hi Oleksandr,

> On 4 Oct 2021, at 3:11 pm, Oleksandr Andrushchenko <andr2000@gmail.com> 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>

Reviewed-by: Rahul Singh <rahul.singh@arm.com>
Tested-by: Rahul Singh <rahul.singh@arm.com>

Regards,
Rahul
> ---
> Since v2:
> - !! dropped Stefano's r-b because of the changes
> - s/PRI_pci/%pp after rebase onto Arm series
> ---
> xen/arch/arm/pci/pci-host-common.c | 16 ++++++++++++++++
> xen/include/asm-arm/pci.h          |  1 +
> 2 files changed, 17 insertions(+)
> 
> diff --git a/xen/arch/arm/pci/pci-host-common.c b/xen/arch/arm/pci/pci-host-common.c
> index 593beeb48ce4..592c01aae5bb 100644
> --- a/xen/arch/arm/pci/pci-host-common.c
> +++ b/xen/arch/arm/pci/pci-host-common.c
> @@ -276,6 +276,22 @@ 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 %pp\n", &pdev->sbdf);
> +        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 603a1fc072d1..e6d4000e2ac8 100644
> --- a/xen/include/asm-arm/pci.h
> +++ b/xen/include/asm-arm/pci.h
> @@ -99,6 +99,7 @@ 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
> 
>