Hi Richard, On Tue, Feb 8, 2022 at 12:57 AM Richard Zhu <hongxing.zhu@xxxxxxx> wrote: > > Since i.MX PCIe doesn't support the hot-plug, and to save power > consumption as much as possible. Return error and disable the enabled > clocks and regulators when link is down,. It is OK to disable clocks and regulators, but I don't think we should return an error on dw_pcie_wait_for_link() failure. Please check: https://git.kernel.org/pub/scm/linux/kernel/git/lpieralisi/pci.git/commit/?h=pci/imx6&id=f81f095e87715e198471f4653952fe5e3f824874 and https://git.kernel.org/pub/scm/linux/kernel/git/lpieralisi/pci.git/commit/?h=pci/imx6&id=886a9c134755 as to why all the dwc PCI drivers should treat dw_pcie_wait_for_link() uniformly. > > Add a new host_exit() callback for i.MX PCIe driver to disable the > enabled clocks, regulators and so on in the error handling after > host_init is finished. > > Signed-off-by: Richard Zhu <hongxing.zhu@xxxxxxx> > --- > drivers/pci/controller/dwc/pci-imx6.c | 30 ++++++++++++++++++++++++--- > 1 file changed, 27 insertions(+), 3 deletions(-) > > diff --git a/drivers/pci/controller/dwc/pci-imx6.c b/drivers/pci/controller/dwc/pci-imx6.c > index e165ad00989c..7a7d9204c6bc 100644 > --- a/drivers/pci/controller/dwc/pci-imx6.c > +++ b/drivers/pci/controller/dwc/pci-imx6.c > @@ -848,7 +848,9 @@ 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_reset_phy; > > if (pci->link_gen == 2) { > /* Allow Gen2 mode after the link is up. */ > @@ -884,7 +886,9 @@ static int imx6_pcie_start_link(struct dw_pcie *pci) > } > > /* 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_reset_phy; > } else { > dev_info(dev, "Link: Gen2 disabled\n"); > } > @@ -897,7 +901,6 @@ static int imx6_pcie_start_link(struct dw_pcie *pci) > 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); > return ret; > } > > @@ -921,8 +924,29 @@ static int imx6_pcie_host_init(struct pcie_port *pp) > return 0; > } > > +static void imx6_pcie_host_exit(struct pcie_port *pp) > +{ > + struct dw_pcie *pci = to_dw_pcie_from_pp(pp); > + struct device *dev = pci->dev; > + struct imx6_pcie *imx6_pcie = to_imx6_pcie(pci); > + > + imx6_pcie_reset_phy(imx6_pcie); > + imx6_pcie_clk_disable(imx6_pcie); > + switch (imx6_pcie->drvdata->variant) { > + case IMX8MM: > + if (phy_power_off(imx6_pcie->phy)) > + dev_err(dev, "unable to power off phy\n"); > + break; > + default: > + break; > + } > + if (imx6_pcie->vpcie) > + regulator_disable(imx6_pcie->vpcie); > +} > + > static const struct dw_pcie_host_ops imx6_pcie_host_ops = { > .host_init = imx6_pcie_host_init, > + .host_exit = imx6_pcie_host_exit, > }; > > static const struct dw_pcie_ops dw_pcie_ops = { > -- > 2.25.1 >
