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It causes unnecessary timeout in L1. > > Workaround: Program GEN3_RELATED_OFF[GEN3_ZRXDC_NONCOMPL] to 0. > > Signed-off-by: Richard Zhu > --- > drivers/pci/controller/dwc/pci-imx6.c | 33 +++++++++++++++++++++++++++ > 1 file changed, 33 insertions(+) > > diff --git a/drivers/pci/controller/dwc/pci-imx6.c b/drivers/pci/controller/dwc/pci-imx6.c > index fbab5a4621aa..42683d6be9f2 100644 > --- a/drivers/pci/controller/dwc/pci-imx6.c > +++ b/drivers/pci/controller/dwc/pci-imx6.c > @@ -1261,6 +1261,37 @@ static void imx_pcie_host_exit(struct dw_pcie_rp *pp) > regulator_disable(imx_pcie->vpcie); > } > > +static void imx_pcie_host_post_init(struct dw_pcie_rp *pp) > +{ > + struct dw_pcie *pci = to_dw_pcie_from_pp(pp); > + struct imx_pcie *imx_pcie = to_imx_pcie(pci); > + u32 val; > + > + switch (imx_pcie->drvdata->variant) { > + case IMX95: > + case IMX95_EP: Use quirk flags if (imx_pcie->drvdata->flags & IMX6_8GT_ECN_51586 ) { ... } Frank > + /* > + * ERR051586: Compliance with 8GT/s Receiver Impedance ECN > + * > + * The default value of GEN3_RELATED_OFF[GEN3_ZRXDC_NONCOMPL] > + * is 1 which makes receiver non-compliant with the ZRX-DC > + * parameter for 2.5 GT/s when operating at 8 GT/s or higher. > + * It causes unnecessary timeout in L1. > + * > + * Workaround: Program GEN3_RELATED_OFF[GEN3_ZRXDC_NONCOMPL] > + * to 0. > + */ > + dw_pcie_dbi_ro_wr_en(pci); > + val = dw_pcie_readl_dbi(pci, GEN3_RELATED_OFF); > + val &= ~GEN3_RELATED_OFF_GEN3_ZRXDC_NONCOMPL; > + dw_pcie_writel_dbi(pci, GEN3_RELATED_OFF, val); > + dw_pcie_dbi_ro_wr_dis(pci); > + break; > + default: > + break; > + } > +} > + > static u64 imx_pcie_cpu_addr_fixup(struct dw_pcie *pcie, u64 cpu_addr) > { > struct imx_pcie *imx_pcie = to_imx_pcie(pcie); > @@ -1302,6 +1333,7 @@ static const struct dw_pcie_host_ops imx_pcie_host_ops = { > static const struct dw_pcie_host_ops imx_pcie_host_dw_pme_ops = { > .init = imx_pcie_host_init, > .deinit = imx_pcie_host_exit, > + .post_init = imx_pcie_host_post_init, > }; > > static const struct dw_pcie_ops dw_pcie_ops = { > @@ -1401,6 +1433,7 @@ static int imx_add_pcie_ep(struct imx_pcie *imx_pcie, > struct device *dev = pci->dev; > > imx_pcie_host_init(pp); > + imx_pcie_host_post_init(pp); > ep = &pci->ep; > ep->ops = &pcie_ep_ops; > > -- > 2.37.1 >