From: Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>
To: "Lorenzo Pieralisi" <lpieralisi@kernel.org>,
"Krzysztof Wilczyński" <kw@linux.com>,
"Rob Herring" <robh@kernel.org>,
"Bjorn Helgaas" <bhelgaas@google.com>,
"Kishon Vijay Abraham I" <kishon@kernel.org>,
"Thierry Reding" <thierry.reding@gmail.com>,
"Jonathan Hunter" <jonathanh@nvidia.com>,
"Jingoo Han" <jingoohan1@gmail.com>
Cc: linux-pci@vger.kernel.org, linux-arm-msm@vger.kernel.org,
linux-kernel@vger.kernel.org, mhi@lists.linux.dev,
linux-tegra@vger.kernel.org, Niklas Cassel <cassel@kernel.org>,
Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>
Subject: [PATCH v2 10/10] PCI: qcom: Implement shutdown() callback to properly reset the endpoint devices
Date: Mon, 01 Apr 2024 21:20:36 +0530 [thread overview]
Message-ID: <20240401-pci-epf-rework-v2-10-970dbe90b99d@linaro.org> (raw)
In-Reply-To: <20240401-pci-epf-rework-v2-0-970dbe90b99d@linaro.org>
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 <manivannan.sadhasivam@linaro.org>
---
drivers/pci/controller/dwc/pcie-qcom.c | 8 ++++++++
1 file changed, 8 insertions(+)
diff --git a/drivers/pci/controller/dwc/pcie-qcom.c b/drivers/pci/controller/dwc/pcie-qcom.c
index 14772edcf0d3..b2803978c0ad 100644
--- a/drivers/pci/controller/dwc/pcie-qcom.c
+++ b/drivers/pci/controller/dwc/pcie-qcom.c
@@ -1655,6 +1655,13 @@ 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 },
@@ -1708,5 +1715,6 @@ 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);
--
2.25.1
next prev parent reply other threads:[~2024-04-01 15:51 UTC|newest]
Thread overview: 30+ messages / expand[flat|nested] mbox.gz Atom feed top
2024-04-01 15:50 [PATCH v2 00/10] PCI: endpoint: Make host reboot handling more robust Manivannan Sadhasivam
2024-04-01 15:50 ` [PATCH v2 01/10] PCI: qcom-ep: Disable resources unconditionally during PERST# assert Manivannan Sadhasivam
2024-04-01 15:50 ` [PATCH v2 02/10] PCI: endpoint: Decouple EPC and PCIe bus specific events Manivannan Sadhasivam
2024-04-02 0:14 ` Damien Le Moal
2024-04-03 14:26 ` Manivannan Sadhasivam
2024-04-04 2:40 ` Damien Le Moal
2024-04-01 15:50 ` [PATCH v2 03/10] PCI: endpoint: Rename core_init() callback in 'struct pci_epc_event_ops' to init() Manivannan Sadhasivam
2024-04-02 10:52 ` Niklas Cassel
2024-04-03 13:46 ` Manivannan Sadhasivam
2024-04-03 15:51 ` Manivannan Sadhasivam
2024-04-01 15:50 ` [PATCH v2 04/10] PCI: epf-test: Refactor pci_epf_test_unbind() function Manivannan Sadhasivam
2024-04-01 15:50 ` [PATCH v2 05/10] PCI: epf-{mhi/test}: Move DMA initialization to EPC init callback Manivannan Sadhasivam
2024-04-01 15:50 ` [PATCH v2 06/10] PCI: endpoint: Introduce EPC 'deinit' event and notify the EPF drivers Manivannan Sadhasivam
2024-04-01 15:50 ` [PATCH v2 07/10] PCI: dwc: ep: Add a generic dw_pcie_ep_linkdown() API to handle Link Down event Manivannan Sadhasivam
2024-04-02 10:52 ` Niklas Cassel
2024-04-01 15:50 ` [PATCH v2 08/10] PCI: qcom-ep: Use the " Manivannan Sadhasivam
2024-04-01 15:50 ` [PATCH v2 09/10] PCI: epf-test: Handle " Manivannan Sadhasivam
2024-04-01 15:50 ` Manivannan Sadhasivam [this message]
2024-04-02 11:18 ` [PATCH v2 10/10] PCI: qcom: Implement shutdown() callback to properly reset the endpoint devices Niklas Cassel
2024-04-03 13:32 ` Manivannan Sadhasivam
2024-04-03 20:03 ` Niklas Cassel
2024-04-09 13:31 ` Bjorn Helgaas
2024-04-10 10:54 ` Manivannan Sadhasivam
2024-04-10 14:52 ` Niklas Cassel
2024-04-10 21:10 ` Niklas Cassel
2024-04-12 6:32 ` Manivannan Sadhasivam
2024-04-02 9:41 ` [PATCH v2 00/10] PCI: endpoint: Make host reboot handling more robust Niklas Cassel
2024-04-03 13:48 ` Manivannan Sadhasivam
2024-04-08 9:49 ` Niklas Cassel
2024-04-02 10:52 ` Niklas Cassel
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