Things like "Use correct ..." in subject lines are useless. *Every*
patch should do the "proper" or "correct" thing, so it should go
without saying. Repeating it doesn't make it more true.
This doesn't apply to *all* loongson devices, so it would be useful to
hint at the devices it *does* apply to.
Maybe something like:
PCI: loongson: Use generic 8/16/32-bit config ops on LS2K/LS7A
On Wed, Aug 25, 2021 at 02:07:20PM +0800, Huacai Chen wrote:
> LS2K/LS7A support 8/16/32-bits pci config access operations via CFG1, so
> we can disable CFG0 for them and safely use pci_generic_config_read()/
> pci_generic_config_write() instead of pci_generic_config_read32()/pci_
> generic_config_write32().
s/pci/PCI/
> Signed-off-by: Huacai Chen <chenhuacai@xxxxxxxxxxx>
> ---
> drivers/pci/controller/pci-loongson.c | 36 +++++++++++++++++----------
> 1 file changed, 23 insertions(+), 13 deletions(-)
>
> diff --git a/drivers/pci/controller/pci-loongson.c b/drivers/pci/controller/pci-loongson.c
> index 48169b1e3817..b2c81c762599 100644
> --- a/drivers/pci/controller/pci-loongson.c
> +++ b/drivers/pci/controller/pci-loongson.c
> @@ -159,8 +159,15 @@ static int loongson_map_irq(const struct pci_dev *dev, u8 slot, u8 pin)
> return val;
> }
>
> -/* H/w only accept 32-bit PCI operations */
> +/* LS2K/LS7A accept 8/16/32-bit PCI operations */
*config* operations
> static struct pci_ops loongson_pci_ops = {
> + .map_bus = pci_loongson_map_bus,
> + .read = pci_generic_config_read,
> + .write = pci_generic_config_write,
> +};
> +
> +/* RS780/SR5690 only accept 32-bit PCI operations */
> +static struct pci_ops loongson_pci_ops32 = {
> .map_bus = pci_loongson_map_bus,
> .read = pci_generic_config_read32,
> .write = pci_generic_config_write32,
> @@ -168,9 +175,9 @@ static struct pci_ops loongson_pci_ops = {
>
> static const struct of_device_id loongson_pci_of_match[] = {
> { .compatible = "loongson,ls2k-pci",
> - .data = (void *)(FLAG_CFG0 | FLAG_CFG1 | FLAG_DEV_FIX), },
> + .data = (void *)(FLAG_CFG1 | FLAG_DEV_FIX), },
> { .compatible = "loongson,ls7a-pci",
> - .data = (void *)(FLAG_CFG0 | FLAG_CFG1 | FLAG_DEV_FIX), },
> + .data = (void *)(FLAG_CFG1 | FLAG_DEV_FIX), },
> { .compatible = "loongson,rs780e-pci",
> .data = (void *)(FLAG_CFG0), },
It'd be nice if you used the same strategy as most other drivers,
e.g., ".data = &loongson_ls2k_data" or similar.
> {}
> @@ -195,17 +202,17 @@ static int loongson_pci_probe(struct platform_device *pdev)
> priv->pdev = pdev;
> priv->flags = (unsigned long)of_device_get_match_data(dev);
>
> - regs = platform_get_resource(pdev, IORESOURCE_MEM, 0);
> - if (!regs) {
> - dev_err(dev, "missing mem resources for cfg0\n");
> - return -EINVAL;
> + if (priv->flags & FLAG_CFG0) {
> + regs = platform_get_resource(pdev, IORESOURCE_MEM, 0);
> + if (!regs)
> + dev_err(dev, "missing mem resources for cfg0\n");
> + else {
> + priv->cfg0_base = devm_pci_remap_cfg_resource(dev, regs);
> + if (IS_ERR(priv->cfg0_base))
> + return PTR_ERR(priv->cfg0_base);
> + }
> }
>
> - priv->cfg0_base = devm_pci_remap_cfg_resource(dev, regs);
> - if (IS_ERR(priv->cfg0_base))
> - return PTR_ERR(priv->cfg0_base);
> -
> - /* CFG1 is optional */
> if (priv->flags & FLAG_CFG1) {
> regs = platform_get_resource(pdev, IORESOURCE_MEM, 1);
> if (!regs)
> @@ -218,8 +225,11 @@ static int loongson_pci_probe(struct platform_device *pdev)
> }
>
> bridge->sysdata = priv;
> - bridge->ops = &loongson_pci_ops;
> bridge->map_irq = loongson_map_irq;
> + if (!of_device_is_compatible(node, "loongson,rs780e-pci"))
You already called of_device_get_match_data() above, which does
essentially the same work as of_device_is_compatible().
> + bridge->ops = &loongson_pci_ops;
> + else
> + bridge->ops = &loongson_pci_ops32;
>
> return pci_host_probe(bridge);
> }
> --
> 2.27.0
>
