Re: [RFC PATCH V5 4/5] ARM64/PCI: Start using quirks handling for ACPI based PCI host controller

[Bjorn Helgaas]

On Mon, Aug 08, 2016 at 03:05:40PM +0200, Tomasz Nowicki wrote:
> Since there are platforms which have non-compliant ECAM space we need to
> override these accessors prior to PCI buses enumeration. In order to do
> that we call pci_mcfg_match_quirks() to retrieve custom
> pci_config_window structure. If no correlated quirk on list, use
> fully ECAM compliant generic PCI config accessors.
> 
> Signed-off-by: Tomasz Nowicki <tn@xxxxxxxxxxxx>
> ---
>  arch/arm64/kernel/pci.c | 3 +--
>  1 file changed, 1 insertion(+), 2 deletions(-)
> 
> diff --git a/arch/arm64/kernel/pci.c b/arch/arm64/kernel/pci.c
> index 2e7bed4..aa734bd 100644
> --- a/arch/arm64/kernel/pci.c
> +++ b/arch/arm64/kernel/pci.c
> @@ -139,8 +139,7 @@ struct pci_bus *pci_acpi_scan_root(struct acpi_pci_root *root)
>  	if (!ri)
>  		return NULL;
>  
> -	ri->cfg = pci_acpi_setup_ecam_mapping(root,
> -					      &pci_generic_ecam_ops.pci_ops);
> +	ri->cfg = pci_mcfg_match_quirks(root);

I don't really like this part: previously it was obvious that we're
setting up ECAM mappings, and now it's not.  I think the quirk
functionality should be buried somewhere inside; it shouldn't be
something this generic code has to worry about.

>  	if (!ri->cfg) {
>  		kfree(ri);
>  		return NULL;
> -- 
> 1.9.1
>