[PATCH] PCI: imx6: Fix link initialisation when the phy is ref clk provider

[Bjorn Helgaas]

Would you mind rewording the subject so it says something more
specific about what the patch does?  E.g.,

  PCI: imx6: Initialize PHY before deasserting core reset

It may be that this ordering is only *required* when the PHY is the
ref clk provider, but the patch doesn't test for that; it *always*
initializes the PHY first.

On Wed, Oct 12, 2022 at 03:26:34PM +0200, Sascha Hauer wrote:
> When the phy is the reference clock provider then it must be initialised
> and powered on before the reset on the client is deasserted, otherwise
> the link will never come up. The order was changed in cf236e0c0d59.
> Restore the correct order to make the driver work again on boards where
> the phy provides the reference clock.

s/phy/PHY/ several places above

> Fixes: cf236e0c0d59 ("PCI: imx6: Do not hide PHY driver callbacks and refine the error handling")
> Signed-off-by: Sascha Hauer <s.hauer at pengutronix.de>
> ---
>  drivers/pci/controller/dwc/pci-imx6.c | 13 +++++++------
>  1 file changed, 7 insertions(+), 6 deletions(-)
> 
> diff --git a/drivers/pci/controller/dwc/pci-imx6.c b/drivers/pci/controller/dwc/pci-imx6.c
> index b5f0de455a7bd..211eb55d6d34b 100644
> --- a/drivers/pci/controller/dwc/pci-imx6.c
> +++ b/drivers/pci/controller/dwc/pci-imx6.c
> @@ -942,12 +942,6 @@ static int imx6_pcie_host_init(struct dw_pcie_rp *pp)
>  		}
>  	}
>  
> -	ret = imx6_pcie_deassert_core_reset(imx6_pcie);
> -	if (ret < 0) {
> -		dev_err(dev, "pcie deassert core reset failed: %d\n", ret);
> -		goto err_phy_off;
> -	}
> -
>  	if (imx6_pcie->phy) {
>  		ret = phy_power_on(imx6_pcie->phy);
>  		if (ret) {
> @@ -955,6 +949,13 @@ static int imx6_pcie_host_init(struct dw_pcie_rp *pp)
>  			goto err_phy_off;
>  		}
>  	}
> +
> +	ret = imx6_pcie_deassert_core_reset(imx6_pcie);
> +	if (ret < 0) {
> +		dev_err(dev, "pcie deassert core reset failed: %d\n", ret);
> +		goto err_phy_off;
> +	}
> +
>  	imx6_setup_phy_mpll(imx6_pcie);
>  
>  	return 0;
> -- 
> 2.30.2
>