linux-kernel - Re: [Intel-gfx] [PATCH V3 09/29] drm/i915: deprecate pci_get_bus_and_slot()

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Message-ID: <20171128153051.GU10981@intel.com>
Date:   Tue, 28 Nov 2017 17:30:51 +0200
From:   Ville Syrjälä <ville.syrjala@...ux.intel.com>
To:     Sinan Kaya <okaya@...eaurora.org>
Cc:     linux-pci@...r.kernel.org, timur@...eaurora.org,
        David Airlie <airlied@...ux.ie>, linux-arm-msm@...r.kernel.org,
        intel-gfx@...ts.freedesktop.org,
        open list <linux-kernel@...r.kernel.org>,
        "open list:DRM DRIVERS" <dri-devel@...ts.freedesktop.org>,
        Rodrigo Vivi <rodrigo.vivi@...el.com>,
        linux-arm-kernel@...ts.infradead.org
Subject: Re: [Intel-gfx] [PATCH V3 09/29] drm/i915: deprecate
 pci_get_bus_and_slot()

On Mon, Nov 27, 2017 at 11:57:46AM -0500, Sinan Kaya wrote:
> pci_get_bus_and_slot() is restrictive such that it assumes domain=0 as
> where a PCI device is present. This restricts the device drivers to be
> reused for other domain numbers.
> 
> Getting ready to remove pci_get_bus_and_slot() function in favor of
> pci_get_domain_bus_and_slot().
> 
> Extract the domain number from drm_device and pass it into
> pci_get_domain_bus_and_slot() function.
> 
> Signed-off-by: Sinan Kaya <okaya@...eaurora.org>
> ---
>  drivers/gpu/drm/i915/i915_drv.c | 5 ++++-
>  1 file changed, 4 insertions(+), 1 deletion(-)
> 
> diff --git a/drivers/gpu/drm/i915/i915_drv.c b/drivers/gpu/drm/i915/i915_drv.c
> index 9f45cfe..5a8cb79 100644
> --- a/drivers/gpu/drm/i915/i915_drv.c
> +++ b/drivers/gpu/drm/i915/i915_drv.c
> @@ -419,7 +419,10 @@ static int i915_getparam(struct drm_device *dev, void *data,
>  
>  static int i915_get_bridge_dev(struct drm_i915_private *dev_priv)
>  {
> -	dev_priv->bridge_dev = pci_get_bus_and_slot(0, PCI_DEVFN(0, 0));
> +	int domain = pci_domain_nr(dev_priv->drm.pdev->bus);
> +
> +	dev_priv->bridge_dev =
> +		pci_get_domain_bus_and_slot(domain, 0, PCI_DEVFN(0, 0));

Maybe just pci_get_slot(pdev->bus, PCI_DEVFN(0, 0)) ?

I guess if we want to be pedantic we could go for:

bus = pci_find_host_bridge(pdev->bus)->bus;
pci_get_slot(bus, PCI_DEVFN(0, 0))

but I think the GPU should always be on the root bus, so the simpler
form should be fine.

>  	if (!dev_priv->bridge_dev) {
>  		DRM_ERROR("bridge device not found\n");
>  		return -1;
> -- 
> 1.9.1
> 
> _______________________________________________
> Intel-gfx mailing list
> Intel-gfx@...ts.freedesktop.org
> https://lists.freedesktop.org/mailman/listinfo/intel-gfx

-- 
Ville Syrjälä
Intel OTC

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