Capitalize subject line to match other commits:
930c6074d7dd ("PCI: loongson: Work around LS7A incorrect Interrupt Pin registers")
2410e3301fcc ("PCI: loongson: Don't access non-existent devices")
cd89edda4002 ("PCI: loongson: Add ACPI init support")
dee449aafd48 ("PCI: loongson: Use generic 8/16/32-bit config ops on LS2K/LS7A")
On Fri, Nov 04, 2022 at 06:53:40PM +0800, Liu Peibao wrote:
> The PCI Controller of 2k1000 could not mask devices by
> setting vender id or device id in configuration space header
> as invalid values. When there are pins shareble between
> the platform device and PCI device, if the platform device
> is preferred, we should not scan this PCI device. In the
> above scene, add `status = "disabled"` property in DT node
> of this PCI device.
Rewrap this to fill 75 columns.
s/id/ID/
s/shareble/shareable/
> Signed-off-by: Liu Peibao <liupeibao@xxxxxxxxxxx>
> ---
> V2 -> V3: 1. use list_for_each_entry() for more clearly.
> 2. fix wrong use of sizeof().
> V1 -> V2: use existing property "status" instead of adding new property.
>
>
> drivers/pci/controller/pci-loongson.c | 55 +++++++++++++++++++++++++++
> 1 file changed, 55 insertions(+)
>
> diff --git a/drivers/pci/controller/pci-loongson.c b/drivers/pci/controller/pci-loongson.c
> index 05c50408f13b..c7dd88eac885 100644
> --- a/drivers/pci/controller/pci-loongson.c
> +++ b/drivers/pci/controller/pci-loongson.c
> @@ -40,11 +40,21 @@ struct loongson_pci_data {
> struct pci_ops *ops;
> };
>
> +#ifdef CONFIG_OF
> +struct mask_entry {
> + struct list_head entry;
> + unsigned int devfn;
> +};
> +#endif
> +
> struct loongson_pci {
> void __iomem *cfg0_base;
> void __iomem *cfg1_base;
> struct platform_device *pdev;
> const struct loongson_pci_data *data;
> +#ifdef CONFIG_OF
> + struct list_head masklist;
> +#endif
> };
>
> /* Fixup wrong class code in PCIe bridges */
> @@ -194,6 +204,18 @@ static void __iomem *pci_loongson_map_bus(struct pci_bus *bus,
> return NULL;
> }
>
> +#ifdef CONFIG_OF
> + /* Don't access devices in masklist */
> + if (pci_is_root_bus(bus)) {
> + struct mask_entry *entry;
> +
> + list_for_each_entry(entry, &priv->masklist, entry) {
> + if (devfn == entry->devfn)
> + return NULL;
> + }
> + }
> +#endif
I would probably get rid of the masklist and just search for a disabled
property when reading config offset 0 (vendor ID). That's not a
performance path anyway. And this seems similar to the
FLAG_DEV_HIDDEN path where you probably don't need to do it for all
controllers.
> /* CFG0 can only access standard space */
> if (where < PCI_CFG_SPACE_SIZE && priv->cfg0_base)
> return cfg0_map(priv, bus, devfn, where);
> @@ -206,6 +228,36 @@ static void __iomem *pci_loongson_map_bus(struct pci_bus *bus,
> }
>
> #ifdef CONFIG_OF
> +static int setup_masklist(struct loongson_pci *priv)
> +{
> + struct device *dev = &priv->pdev->dev;
> + struct device_node *dn, *parent = dev->of_node;
> + struct mask_entry *entry;
> + int devfn;
> +
> + INIT_LIST_HEAD(&priv->masklist);
> +
> + for_each_child_of_node(parent, dn) {
> + /*
> + * if device is not available, add this to masklist
> + * to avoid scanning it.
> + */
> + if (!of_device_is_available(dn)) {
> + devfn = of_pci_get_devfn(dn);
> + if (devfn < 0)
> + continue;
> +
> + entry = devm_kzalloc(dev, sizeof(*entry), GFP_KERNEL);
> + if (!entry)
> + return -ENOMEM;
> +
> + entry->devfn = devfn;
> + list_add_tail(&entry->entry, &priv->masklist);
> + }
> + }
> +
> + return 0;
> +}
>
> static int loongson_map_irq(const struct pci_dev *dev, u8 slot, u8 pin)
> {
> @@ -305,6 +357,9 @@ static int loongson_pci_probe(struct platform_device *pdev)
> }
> }
>
> + if (setup_masklist(priv))
> + return -ENOMEM;
> +
> bridge->sysdata = priv;
> bridge->ops = priv->data->ops;
> bridge->map_irq = loongson_map_irq;
> --
> 2.20.1
>
