From 9a7f144e18dc5f037d85a0f0d99524a574331098 Mon Sep 17 00:00:00 2001 From: Siddharth Vadapalli Date: Mon, 1 Sep 2025 17:33:55 +0530 Subject: [PATCH 1/3] PCI: j721e: Fix module autoloading Commit a2790bf81f0f ("PCI: j721e: Add support to build as a loadable module") added support to build the driver as a loadable module. However, it did not add MODULE_DEVICE_TABLE() which is required for autoloading the driver based on device table when it is built as a loadable module. Fix it by adding MODULE_DEVICE_TABLE. Fixes: a2790bf81f0f ("PCI: j721e: Add support to build as a loadable module") Signed-off-by: Siddharth Vadapalli [mani: reworded description] Signed-off-by: Manivannan Sadhasivam Cc: stable@vger.kernel.org Link: https://patch.msgid.link/20250901120359.3410774-1-s-vadapalli@ti.com --- drivers/pci/controller/cadence/pci-j721e.c | 1 + 1 file changed, 1 insertion(+) diff --git a/drivers/pci/controller/cadence/pci-j721e.c b/drivers/pci/controller/cadence/pci-j721e.c index 6c93f39d0288..cfca13a4c840 100644 --- a/drivers/pci/controller/cadence/pci-j721e.c +++ b/drivers/pci/controller/cadence/pci-j721e.c @@ -440,6 +440,7 @@ 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) { From f842d3313ba179d4005096357289c7ad09cec575 Mon Sep 17 00:00:00 2001 From: Siddharth Vadapalli Date: Mon, 8 Sep 2025 17:38:27 +0530 Subject: [PATCH 2/3] PCI: j721e: Fix programming sequence of "strap" settings The Cadence PCIe Controller integrated in the TI K3 SoCs supports both Root-Complex and Endpoint modes of operation. The Glue Layer allows "strapping" the Mode of operation of the Controller, the Link Speed and the Link Width. This is enabled by programming the "PCIEn_CTRL" register (n corresponds to the PCIe instance) within the CTRL_MMR memory-mapped register space. The "reset-values" of the registers are also different depending on the mode of operation. Since the PCIe Controller latches onto the "reset-values" immediately after being powered on, if the Glue Layer configuration is not done while the PCIe Controller is off, it will result in the PCIe Controller latching onto the wrong "reset-values". In practice, this will show up as a wrong representation of the PCIe Controller's capability structures in the PCIe Configuration Space. Some such capabilities which are supported by the PCIe Controller in the Root-Complex mode but are incorrectly latched onto as being unsupported are: - Link Bandwidth Notification - Alternate Routing ID (ARI) Forwarding Support - Next capability offset within Advanced Error Reporting (AER) capability Fix this by powering off the PCIe Controller before programming the "strap" settings and powering 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. Fixes: f3e25911a430 ("PCI: j721e: Add TI J721E PCIe driver") Signed-off-by: Siddharth Vadapalli Signed-off-by: Manivannan Sadhasivam Cc: stable@vger.kernel.org Link: https://patch.msgid.link/20250908120828.1471776-1-s-vadapalli@ti.com --- drivers/pci/controller/cadence/pci-j721e.c | 25 ++++++++++++++++++++++ 1 file changed, 25 insertions(+) diff --git a/drivers/pci/controller/cadence/pci-j721e.c b/drivers/pci/controller/cadence/pci-j721e.c index cfca13a4c840..5a9ae33e2b93 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"); From cfcd6cab2f33c24a68517f9e3131480b4000c2be Mon Sep 17 00:00:00 2001 From: Alok Tiwari Date: Fri, 5 Sep 2025 14:14:34 -0700 Subject: [PATCH 3/3] PCI: j721e: Fix incorrect error message in probe() The probe() function prints "pm_runtime_get_sync failed" when j721e_pcie_ctrl_init() returns an error. This is misleading since the failure is not from pm_runtime, but from the controller init routine. Update the error message to correctly reflect the source. No functional changes. Fixes: f3e25911a430 ("PCI: j721e: Add TI J721E PCIe driver") Signed-off-by: Alok Tiwari Signed-off-by: Manivannan Sadhasivam Reviewed-by: Siddharth Vadapalli Link: https://patch.msgid.link/20250905211436.3048282-1-alok.a.tiwari@oracle.com --- drivers/pci/controller/cadence/pci-j721e.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/drivers/pci/controller/cadence/pci-j721e.c b/drivers/pci/controller/cadence/pci-j721e.c index 5a9ae33e2b93..5bc5ab20aa6d 100644 --- a/drivers/pci/controller/cadence/pci-j721e.c +++ b/drivers/pci/controller/cadence/pci-j721e.c @@ -575,7 +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; }