Re: [PATCH v2 2/4] PCI: cadence: Use "dma-ranges" instead of "cdns,no-bar-match-nbits" property

[Lorenzo Pieralisi]

[+Robin - to check on dma-ranges intepretation]

I would need RobH and Robin to review this.

Also, An ACK from Tom is required - for the whole series.

On Fri, Apr 17, 2020 at 05:13:20PM +0530, Kishon Vijay Abraham I wrote:
> Cadence PCIe core driver (host mode) uses "cdns,no-bar-match-nbits"
> property to configure the number of bits passed through from PCIe
> address to internal address in Inbound Address Translation register.
> 
> However standard PCI dt-binding already defines "dma-ranges" to
> describe the address range accessible by PCIe controller. Parse
> "dma-ranges" property to configure the number of bits passed
> through from PCIe address to internal address in Inbound Address
> Translation register.
> 
> Signed-off-by: Kishon Vijay Abraham I <kishon@xxxxxx>
> ---
>  drivers/pci/controller/cadence/pcie-cadence-host.c | 13 +++++++++++--
>  1 file changed, 11 insertions(+), 2 deletions(-)
> 
> diff --git a/drivers/pci/controller/cadence/pcie-cadence-host.c b/drivers/pci/controller/cadence/pcie-cadence-host.c
> index 9b1c3966414b..60f912a657b9 100644
> --- a/drivers/pci/controller/cadence/pcie-cadence-host.c
> +++ b/drivers/pci/controller/cadence/pcie-cadence-host.c
> @@ -206,8 +206,10 @@ int cdns_pcie_host_setup(struct cdns_pcie_rc *rc)
>  	struct device *dev = rc->pcie.dev;
>  	struct platform_device *pdev = to_platform_device(dev);
>  	struct device_node *np = dev->of_node;
> +	struct of_pci_range_parser parser;
>  	struct pci_host_bridge *bridge;
>  	struct list_head resources;
> +	struct of_pci_range range;
>  	struct cdns_pcie *pcie;
>  	struct resource *res;
>  	int ret;
> @@ -222,8 +224,15 @@ int cdns_pcie_host_setup(struct cdns_pcie_rc *rc)
>  	rc->max_regions = 32;
>  	of_property_read_u32(np, "cdns,max-outbound-regions", &rc->max_regions);
>  
> -	rc->no_bar_nbits = 32;
> -	of_property_read_u32(np, "cdns,no-bar-match-nbits", &rc->no_bar_nbits);
> +	if (!of_pci_dma_range_parser_init(&parser, np))
> +		if (of_pci_range_parser_one(&parser, &range))
> +			rc->no_bar_nbits = ilog2(range.size);
> +
> +	if (!rc->no_bar_nbits) {
> +		rc->no_bar_nbits = 32;
> +		of_property_read_u32(np, "cdns,no-bar-match-nbits",
> +				     &rc->no_bar_nbits);
> +	}
>  
>  	rc->vendor_id = 0xffff;
>  	of_property_read_u16(np, "vendor-id", &rc->vendor_id);
> -- 
> 2.17.1
>