Re: [PATCH v1] PCI: imx6: Align EP link start behavior with documentation

Frank Li
2025-06-06T15:32:41Z

On Fri, Jun 06, 2025 at 03:57:29PM +0800, Richard Zhu wrote:
> According to PCI/endpoint/pci-endpoint-cfs.rst, the endpoint (EP) should
> only link up after `echo 1 > start` is executed.
>
> To match the documented behavior, do not start the link automatically
> when adding the EP controller. Ensure the LTSSM_EN bit is not asserted
> to 1'b1 by default.

Reviewed-by: Frank Li <Frank.Li@nxp.com>

>
> Signed-off-by: Richard Zhu <hongxing.zhu@nxp.com>
> ---
> drivers/pci/controller/dwc/pci-imx6.c | 7 ++++---
> 1 file changed, 4 insertions(+), 3 deletions(-)
>
> diff --git a/drivers/pci/controller/dwc/pci-imx6.c b/drivers/pci/controller/dwc/pci-imx6.c
> index 5f267dd261b5..69825e47d2d4 100644
> --- a/drivers/pci/controller/dwc/pci-imx6.c
> +++ b/drivers/pci/controller/dwc/pci-imx6.c
> @@ -1337,6 +1337,10 @@ static int imx_add_pcie_ep(struct imx_pcie *imx_pcie,
> struct device *dev = pci->dev;
>
> imx_pcie_host_init(pp);
> +
> + /* Make sure that PCIe LTSSM is cleared */
> + imx_pcie_ltssm_disable(dev);
> +
> ep = &pci->ep;
> ep->ops = &pcie_ep_ops;
>
> @@ -1360,9 +1364,6 @@ static int imx_add_pcie_ep(struct imx_pcie *imx_pcie,
>
> pci_epc_init_notify(ep->epc);
>
> - /* Start LTSSM. */
> - imx_pcie_ltssm_enable(dev);
> -
> return 0;
> }
>
> --
> 2.37.1
>