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a=openpgp; fpr=C668AEC3C3188E4C611465E7488550E901166008 PCIe host controller drivers are supposed to properly reset the endpoint devices during host shutdown/reboot. Currently, Qcom driver doesn't do anything during host shutdown/reboot, resulting in both PERST# and refclk getting disabled at the same time. This prevents the endpoint device firmware to properly reset the state machine. Because, if the refclk is cutoff immediately along with PERST#, access to device specific registers within the endpoint will result in a firmware crash. To address this issue, let's call qcom_pcie_host_deinit() inside the shutdown callback, that asserts PERST# and then cuts off the refclk with a delay of 1ms, thus allowing the endpoint device firmware to properly cleanup the state machine. Signed-off-by: Manivannan Sadhasivam --- drivers/pci/controller/dwc/pcie-qcom.c | 8 ++++++++ 1 file changed, 8 insertions(+) --- base-commit: 51459eb30f88651d3688b9e95fed0f97767ececb change-id: 20240313-pci-qcom-shutdown-d86298186560 Best regards, diff --git a/drivers/pci/controller/dwc/pcie-qcom.c b/drivers/pci/controller/dwc/pcie-qcom.c index 2ce2a3bd932b..41434bc4761a 100644 --- a/drivers/pci/controller/dwc/pcie-qcom.c +++ b/drivers/pci/controller/dwc/pcie-qcom.c @@ -1618,6 +1618,13 @@ static int qcom_pcie_resume_noirq(struct device *dev) return 0; } +static void qcom_pcie_shutdown(struct platform_device *pdev) +{ + struct qcom_pcie *pcie = platform_get_drvdata(pdev); + + qcom_pcie_host_deinit(&pcie->pci->pp); +} + static const struct of_device_id qcom_pcie_match[] = { { .compatible = "qcom,pcie-apq8064", .data = &cfg_2_1_0 }, { .compatible = "qcom,pcie-apq8084", .data = &cfg_1_0_0 }, @@ -1670,5 +1677,6 @@ static struct platform_driver qcom_pcie_driver = { .pm = &qcom_pcie_pm_ops, .probe_type = PROBE_PREFER_ASYNCHRONOUS, }, + .shutdown = qcom_pcie_shutdown, }; builtin_platform_driver(qcom_pcie_driver);