Re: [PATCH] PCI: dw-rockchip: Skip waiting for link up

Bjorn Helgaas
2025-01-13T19:28:50Z

On Mon, Jan 13, 2025 at 11:59:34AM +0100, Niklas Cassel wrote:
> The Root Complex specific device tree binding for pcie-dw-rockchip has the
> 'sys' interrupt marked as required.
>
> The driver requests the 'sys' IRQ unconditionally, and errors out if not
> provided.
>
> Thus, we can unconditionally set use_linkup_irq before calling
> dw_pcie_host_init().
>
> This will skip the wait for link up (since the bus will be enumerated once
> the link up IRQ is triggered), which reduces the bootup time.
>
> Signed-off-by: Niklas Cassel <cassel@kernel.org>

Thanks! I was just reviewing the addition of your dll_link_up IRQ
handler, and was about to ask whether you wanted to set use_linkup_irq
to avoid the wait, but here's the patch already :)

I think I'll sort out the branches so the dll_link_up IRQ handler,
this patch, and the corresponding qcom change go on the same branch as
Krishna's patch to skip waiting if pp->use_linkup_irq.

> ---
> drivers/pci/controller/dwc/pcie-dw-rockchip.c | 1 +
> 1 file changed, 1 insertion(+)
>
> diff --git a/drivers/pci/controller/dwc/pcie-dw-rockchip.c b/drivers/pci/controller/dwc/pcie-dw-rockchip.c
> index 1170e1107508bd793b610949b0afe98516c177a4..62034affb95fbb965aad3cebc613a83e31c90aee 100644
> --- a/drivers/pci/controller/dwc/pcie-dw-rockchip.c
> +++ b/drivers/pci/controller/dwc/pcie-dw-rockchip.c
> @@ -435,6 +435,7 @@ static int rockchip_pcie_configure_rc(struct rockchip_pcie *rockchip)
>
> pp = &rockchip->pci.pp;
> pp->ops = &rockchip_pcie_host_ops;
> + pp->use_linkup_irq = true;
>
> return dw_pcie_host_init(pp);
> }
>
> ---
> base-commit: 2adda4102931b152f35d054055497631ed97fe73
> change-id: 20250113-rockchip-no-wait-403ffbc42313
>
> Best regards,
> --
> Niklas Cassel <cassel@kernel.org>
>