[PATCH] powerpc/fsl-pci: Choose PCI host bridge with alias pci0 as the primary

[Pali Rohár]

Hello! Any opinion on this patch?

On Saturday 20 August 2022 14:33:27 Pali Rohár wrote:
> If there's no PCI host bridge with ISA then check for PCI host bridge with
> alias "pci0" (first PCI host bridge) and if it exists then choose it as the
> primary PCI host bridge.
> 
> This makes choice of primary PCI host bridge more stable across boots and
> updates as the last fallback candidate for primary PCI host bridge (if
> there is no choice) is selected arbitrary.
> 
> Signed-off-by: Pali Rohár <pali at kernel.org>
> ---
>  arch/powerpc/sysdev/fsl_pci.c | 13 +++++++++++++
>  1 file changed, 13 insertions(+)
> 
> diff --git a/arch/powerpc/sysdev/fsl_pci.c b/arch/powerpc/sysdev/fsl_pci.c
> index 1011cfea2e32..e4b703943dd3 100644
> --- a/arch/powerpc/sysdev/fsl_pci.c
> +++ b/arch/powerpc/sysdev/fsl_pci.c
> @@ -1125,6 +1125,19 @@ void __init fsl_pci_assign_primary(void)
>  			return;
>  	}
>  
> +	/*
> +	 * If there's no PCI host bridge with ISA then check for
> +	 * PCI host bridge with alias "pci0" (first PCI host bridge).
> +	 */
> +	np = of_find_node_by_path("pci0");
> +	if (np && of_match_node(pci_ids, np) && of_device_is_available(np)) {
> +		fsl_pci_primary = np;
> +		of_node_put(np);
> +		return;
> +	}
> +	if (np)
> +		of_node_put(np);
> +
>  	/*
>  	 * If there's no PCI host bridge with ISA, arbitrarily
>  	 * designate one as primary.  This can go away once
> -- 
> 2.20.1
>