Re: [RFC 2/4] PCI: generic: Add support for ARM64 and MSI(x)

Arnd Bergmann
2014-09-29T14:37:13Z

On Sunday 28 September 2014 15:53:28 suravee.suthikulpanit@amd.com wrote:
> +
> +#ifdef CONFIG_ARM64
> +struct pci_bus *gen_scan_root_bus(struct device *parent, int bus,
> + struct pci_ops *ops, void *sysdata,
> + struct list_head *resources)
> +{

I don't see anything ARM64 specific in this, the function only uses
the newly added generic helpers.

> static int gen_pci_probe(struct platform_device *pdev)
> {
> @@ -326,6 +385,7 @@ static int gen_pci_probe(struct platform_device *pdev)
> struct device *dev = &pdev->dev;
> struct device_node *np = dev->of_node;
> struct gen_pci *pci = devm_kzalloc(dev, sizeof(*pci), GFP_KERNEL);
> +#ifndef CONFIG_ARM64
> struct hw_pci hw = {
> .nr_controllers = 1,
> .private_data = (void **)&pci,
> @@ -333,6 +393,7 @@ static int gen_pci_probe(struct platform_device *pdev)
> .map_irq = of_irq_parse_and_map_pci,
> .ops = &gen_pci_ops,
> };
> +#endif
>

Same here, I'd suggest marking this "#ifdef CONFIG_ARM" instead, as hw_pci
is an arm32 specific data structure.

> if (!pci)
> return -ENOMEM;
> @@ -368,8 +429,24 @@ static int gen_pci_probe(struct platform_device *pdev)
> gen_pci_release_of_pci_ranges(pci);
> return err;
> }
> +#ifdef CONFIG_ARM64
>
> +#ifdef CONFIG_PCI_MSI
> + pci->msi_parent = of_parse_phandle(np, "msi-parent", 0);
> + if (!pci->msi_parent) {
> + dev_err(&pdev->dev, "Failed to allocate msi-parent.\n");
> + return -EINVAL;
> + }
> +#endif

We probably want to enable MSI unconditionally on ARM64, so the #ifdef is
not necessary here. However, I don't think that a missing msi-parent should
be a fatal error here: we can still continue without MSI support if this
case.

> + if (!gen_scan_root_bus(&pdev->dev, pci->cfg.bus_range.start,
> + &gen_pci_ops, pci, &pci->resources)) {
> + dev_err(&pdev->dev, "failed to enable PCIe ports\n");
> + return -ENODEV;
> + }
> +#else
> pci_common_init_dev(dev, &hw);
> +#endif /* CONFIG_ARM64 */
>

Again, just make the pci_common_init_dev() call #ifdef CONFIG_ARM, and move
the generic case after it, outside of the #ifdef.

Arnd