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charset=utf-8 Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: <20230915184306.2374670-2-Frank.Li@nxp.com> Precedence: bulk List-ID: X-Mailing-List: linux-pci@vger.kernel.org On Fri, Sep 15, 2023 at 02:43:05PM -0400, Frank Li wrote: > ls1021a add suspend/resume support. > Please add what the driver is doing during suspend/resume. > Signed-off-by: Frank Li > --- > drivers/pci/controller/dwc/pci-layerscape.c | 88 ++++++++++++++++++++- > 1 file changed, 87 insertions(+), 1 deletion(-) > > diff --git a/drivers/pci/controller/dwc/pci-layerscape.c b/drivers/pci/controller/dwc/pci-layerscape.c > index 20c48c06e2248..bc5a8ff1a26ce 100644 > --- a/drivers/pci/controller/dwc/pci-layerscape.c > +++ b/drivers/pci/controller/dwc/pci-layerscape.c > @@ -35,6 +35,12 @@ > #define PF_MCR_PTOMR BIT(0) > #define PF_MCR_EXL2S BIT(1) > > +/* LS1021A PEXn PM Write Control Register */ > +#define SCFG_PEXPMWRCR(idx) (0x5c + (idx) * 0x64) > +#define PMXMTTURNOFF BIT(31) > +#define SCFG_PEXSFTRSTCR 0x190 > +#define PEXSR(idx) BIT(idx) > + > #define PCIE_IATU_NUM 6 > > struct ls_pcie_drvdata { > @@ -48,6 +54,8 @@ struct ls_pcie { > struct dw_pcie *pci; > const struct ls_pcie_drvdata *drvdata; > void __iomem *pf_base; > + struct regmap *scfg; > + int index; > bool big_endian; > }; > > @@ -170,13 +178,91 @@ static int ls_pcie_host_init(struct dw_pcie_rp *pp) > return 0; > } > > +static void ls1021a_pcie_send_turnoff_msg(struct dw_pcie_rp *pp) > +{ > + struct dw_pcie *pci = to_dw_pcie_from_pp(pp); > + struct ls_pcie *pcie = to_ls_pcie(pci); > + u32 val; > + > + if (!pcie->scfg) { Can this ever happen? > + dev_dbg(pcie->pci->dev, "SYSCFG is NULL\n"); > + return; > + } > + > + /* Send Turn_off message */ "Send PME_Turn_Off message" > + regmap_read(pcie->scfg, SCFG_PEXPMWRCR(pcie->index), &val); > + val |= PMXMTTURNOFF; > + regmap_write(pcie->scfg, SCFG_PEXPMWRCR(pcie->index), val); > + > + /* There are not register to check ACK, so wait PCIE_PME_TO_L2_TIMEOUT_US */ "There is no specific register to check for PME_To_Ack from endpoint. So on the safe side, wait for PCIE_PME_TO_L2_TIMEOUT_US." > + mdelay(PCIE_PME_TO_L2_TIMEOUT_US/1000); > + > + /* Clear Turn_off message */ "PME_Turn_off". But I'm not sure if this is really required. Are you doing it because the layerspace hw implements the PME_Turn_Off bit as "level triggered"? > + regmap_read(pcie->scfg, SCFG_PEXPMWRCR(pcie->index), &val); > + val &= ~PMXMTTURNOFF; > + regmap_write(pcie->scfg, SCFG_PEXPMWRCR(pcie->index), val); > +} > + > +static void ls1021a_pcie_exit_from_l2(struct dw_pcie_rp *pp) > +{ > + struct dw_pcie *pci = to_dw_pcie_from_pp(pp); > + struct ls_pcie *pcie = to_ls_pcie(pci); > + u32 val; > + A comment here would be good. > + regmap_read(pcie->scfg, SCFG_PEXSFTRSTCR, &val); > + val |= PEXSR(pcie->index); > + regmap_write(pcie->scfg, SCFG_PEXSFTRSTCR, val); > + > + regmap_read(pcie->scfg, SCFG_PEXSFTRSTCR, &val); > + val &= ~PEXSR(pcie->index); > + regmap_write(pcie->scfg, SCFG_PEXSFTRSTCR, val); > +} > + > +static int ls1021a_pcie_host_init(struct dw_pcie_rp *pp) > +{ > + struct dw_pcie *pci = to_dw_pcie_from_pp(pp); > + struct ls_pcie *pcie = to_ls_pcie(pci); > + struct device *dev = pcie->pci->dev; > + u32 index[2]; > + int ret; > + > + ret = ls_pcie_host_init(pp); > + if (ret) > + return ret; > + > + pcie->scfg = syscon_regmap_lookup_by_phandle(dev->of_node, "fsl,pcie-scfg"); > + if (IS_ERR(pcie->scfg)) { > + ret = PTR_ERR(pcie->scfg); > + dev_err(dev, "No syscfg phandle specified\n"); > + pcie->scfg = NULL; > + return ret; > + } > + > + ret = of_property_read_u32_array(dev->of_node, "fsl,pcie-scfg", index, 2); > + if (ret) { > + pcie->scfg = NULL; > + return ret; > + } > + > + pcie->index = index[1]; > + The above syscon parsing could be done conditionally during probe itself. There is no need to do it during host_init() time. - Mani > + return ret; > +} > + > static const struct dw_pcie_host_ops ls_pcie_host_ops = { > .host_init = ls_pcie_host_init, > .pme_turn_off = ls_pcie_send_turnoff_msg, > }; > > +static const struct dw_pcie_host_ops ls1021a_pcie_host_ops = { > + .host_init = ls1021a_pcie_host_init, > + .pme_turn_off = ls1021a_pcie_send_turnoff_msg, > +}; > + > static const struct ls_pcie_drvdata ls1021a_drvdata = { > - .pm_support = false, > + .pm_support = true, > + .ops = &ls1021a_pcie_host_ops, > + .exit_from_l2 = ls1021a_pcie_exit_from_l2, > }; > > static const struct ls_pcie_drvdata layerscape_drvdata = { > -- > 2.34.1 > -- மணிவண்ணன் சதாசிவம்