On Thu, Mar 19, 2020 at 04:54:09PM +0900, Kunihiko Hayashi wrote:
> This introduces specific glue layer for UniPhier platform to support
> PCIe controller that is based on the DesignWare PCIe core, and
> this driver supports endpoint mode. This supports for Pro5 SoC only.
Possible alternate text: ("specific glue layer" isn't the usual way to
describe a driver)
PCI: uniphier: Add Socionext UniPhier Pro5 SoC endpoint controller driver
Add driver for the Socionext UniPhier Pro5 SoC endpoint controller.
This controller is based on the DesignWare PCIe core.
> +/* assertion time of intx in usec */
s/intx/INTx/ to match usage in spec (and in comments below :))
> +#define PCL_INTX_WIDTH_USEC 30
> +struct uniphier_pcie_ep_soc_data {
> + bool is_legacy;
I'd prefer "unsigned int is_legacy:1". See [1].
But AFAICT you actually don't need this at all (yet), since you only
have a single of_device_id, and it sets "is_legacy = true". That
means the *not* legacy code is effectively dead and hasn't been
tested.
My preference would be to add "is_legacy" and the associated tests
when you actually *need* them, i.e., when you add support for a
non-legacy device.
> +static int uniphier_pcie_ep_raise_legacy_irq(struct dw_pcie_ep *ep)
> +{
> + struct dw_pcie *pci = to_dw_pcie_from_ep(ep);
> + struct uniphier_pcie_ep_priv *priv = to_uniphier_pcie(pci);
> + u32 val;
> +
> + /* assert INTx */
> + val = readl(priv->base + PCL_APP_INTX);
> + val |= PCL_APP_INTX_SYS_INT;
> + writel(val, priv->base + PCL_APP_INTX);
> +
> + udelay(PCL_INTX_WIDTH_USEC);
> +
> + /* deassert INTx */
> + val = readl(priv->base + PCL_APP_INTX);
Why do you need to read PCL_APP_INTX again here?
> + val &= ~PCL_APP_INTX_SYS_INT;
> + writel(val, priv->base + PCL_APP_INTX);
> +
> + return 0;
> +}
> + ret = dw_pcie_ep_init(ep);
> + if (ret) {
> + dev_err(dev, "Failed to initialize endpoint (%d)\n", ret);
> + return ret;
> + }
> +
> + return 0;
This is equivalent to:
ret = dw_pcie_ep_init(ep);
if (ret)
dev_err(dev, "Failed to initialize endpoint (%d)\n", ret);
return ret;
> +}
[1] https://lore.kernel.org/linux-fsdevel/CA+55aFzKQ6Pj18TB8p4Yr0M4t+S+BsiHH=BJNmn=76-NcjTj-g@xxxxxxxxxxxxxx/
