Am Freitag, dem 06.05.2022 um 09:47 +0800 schrieb Richard Zhu:
> Since i.MX PCIe doesn't support hot-plug, reduce power consumption
> as much as possible by disabling clocks and regulators and returning
> error when the link is down.
>
> Signed-off-by: Richard Zhu <hongxing.zhu@xxxxxxx>
> ---
> drivers/pci/controller/dwc/pci-imx6.c | 19 +++++++++++++++----
> 1 file changed, 15 insertions(+), 4 deletions(-)
>
> diff --git a/drivers/pci/controller/dwc/pci-imx6.c b/drivers/pci/controller/dwc/pci-imx6.c
> index 3ce3993d5797..d122c12193a6 100644
> --- a/drivers/pci/controller/dwc/pci-imx6.c
> +++ b/drivers/pci/controller/dwc/pci-imx6.c
> @@ -845,7 +845,9 @@ static int imx6_pcie_start_link(struct dw_pcie *pci)
> /* Start LTSSM. */
> imx6_pcie_ltssm_enable(dev);
>
> - dw_pcie_wait_for_link(pci);
> + ret = dw_pcie_wait_for_link(pci);
> + if (ret)
> + goto err_out;
This adds back error handling that has been intentionally removed in
f81f095e8771 ("PCI: imx6: Allow to probe when dw_pcie_wait_for_link()
fails"). While I agree that disabling the clocks and regulators is the
right thing to do when we don't manage to get a link, we should still
allow the driver to probe, so please add a "ret = 0" to this newly
added non-fatal error paths.
>
> if (pci->link_gen == 2) {
> /* Allow Gen2 mode after the link is up. */
> @@ -876,12 +878,14 @@ static int imx6_pcie_start_link(struct dw_pcie *pci)
> ret = imx6_pcie_wait_for_speed_change(imx6_pcie);
> if (ret) {
> dev_err(dev, "Failed to bring link up!\n");
> - goto err_reset_phy;
> + goto err_out;
> }
> }
>
> /* Make sure link training is finished as well! */
> - dw_pcie_wait_for_link(pci);
> + ret = dw_pcie_wait_for_link(pci);
> + if (ret)
> + goto err_out;
> } else {
> dev_info(dev, "Link: Gen2 disabled\n");
> }
> @@ -890,11 +894,18 @@ static int imx6_pcie_start_link(struct dw_pcie *pci)
> dev_info(dev, "Link up, Gen%i\n", tmp & PCI_EXP_LNKSTA_CLS);
> return 0;
>
> -err_reset_phy:
> +err_out:
> dev_dbg(dev, "PHY DEBUG_R0=0x%08x DEBUG_R1=0x%08x\n",
> dw_pcie_readl_dbi(pci, PCIE_PORT_DEBUG0),
> dw_pcie_readl_dbi(pci, PCIE_PORT_DEBUG1));
> imx6_pcie_reset_phy(imx6_pcie);
> + imx6_pcie_clk_disable(imx6_pcie);
> + if (imx6_pcie->phy != NULL) {
Please use the more common if (imx6_pcie->phy) here.
Regards,
Lucas
> + phy_power_off(imx6_pcie->phy);
> + phy_exit(imx6_pcie->phy);
> + }
> + if (imx6_pcie->vpcie)
> + regulator_disable(imx6_pcie->vpcie);
> return ret;
> }
>
