diff options
Diffstat (limited to 'drivers/pci/controller/cadence/pci-j721e.c')
| -rw-r--r-- | drivers/pci/controller/cadence/pci-j721e.c | 28 |
1 files changed, 27 insertions, 1 deletions
diff --git a/drivers/pci/controller/cadence/pci-j721e.c b/drivers/pci/controller/cadence/pci-j721e.c index 6c93f39d0288..5bc5ab20aa6d 100644 --- a/drivers/pci/controller/cadence/pci-j721e.c +++ b/drivers/pci/controller/cadence/pci-j721e.c @@ -284,6 +284,25 @@ static int j721e_pcie_ctrl_init(struct j721e_pcie *pcie) if (!ret) offset = args.args[0]; + /* + * The PCIe Controller's registers have different "reset-values" + * depending on the "strap" settings programmed into the PCIEn_CTRL + * register within the CTRL_MMR memory-mapped register space. + * The registers latch onto a "reset-value" based on the "strap" + * settings sampled after the PCIe Controller is powered on. + * To ensure that the "reset-values" are sampled accurately, power + * off the PCIe Controller before programming the "strap" settings + * and power it on after that. The runtime PM APIs namely + * pm_runtime_put_sync() and pm_runtime_get_sync() will decrement and + * increment the usage counter respectively, causing GENPD to power off + * and power on the PCIe Controller. + */ + ret = pm_runtime_put_sync(dev); + if (ret < 0) { + dev_err(dev, "Failed to power off PCIe Controller\n"); + return ret; + } + ret = j721e_pcie_set_mode(pcie, syscon, offset); if (ret < 0) { dev_err(dev, "Failed to set pci mode\n"); @@ -302,6 +321,12 @@ static int j721e_pcie_ctrl_init(struct j721e_pcie *pcie) return ret; } + ret = pm_runtime_get_sync(dev); + if (ret < 0) { + dev_err(dev, "Failed to power on PCIe Controller\n"); + return ret; + } + /* Enable ACSPCIE refclk output if the optional property exists */ syscon = syscon_regmap_lookup_by_phandle_optional(node, "ti,syscon-acspcie-proxy-ctrl"); @@ -440,6 +465,7 @@ static const struct of_device_id of_j721e_pcie_match[] = { }, {}, }; +MODULE_DEVICE_TABLE(of, of_j721e_pcie_match); static int j721e_pcie_probe(struct platform_device *pdev) { @@ -549,7 +575,7 @@ static int j721e_pcie_probe(struct platform_device *pdev) ret = j721e_pcie_ctrl_init(pcie); if (ret < 0) { - dev_err_probe(dev, ret, "pm_runtime_get_sync failed\n"); + dev_err_probe(dev, ret, "j721e_pcie_ctrl_init failed\n"); goto err_get_sync; } |