dmaengine: qcom_hidma: pause the channel on shutdown (dc7c733a) · Commits · 戴 / test

We need to ensure that all DMAs and interrupts are cleared during shutdown operation in order for kexec to start the next kernel clearly. Otherwise, HW could be performing a DMA into random addresses in the middle of second kernel start. Signed-off-by:

Sinan Kaya <okaya@codeaurora.org> Signed-off-by:

Vinod Koul <vinod.koul@intel.com>

drivers/dma/qcom/hidma.c

+15 −0

Original line number	Diff line number	Diff line
		@@ -865,6 +865,20 @@ bailout:
		return rc;
		}

		static void hidma_shutdown(struct platform_device *pdev)
		{
		struct hidma_dev *dmadev = platform_get_drvdata(pdev);

		dev_info(dmadev->ddev.dev, "HI-DMA engine shutdown\n");

		pm_runtime_get_sync(dmadev->ddev.dev);
		if (hidma_ll_disable(dmadev->lldev))
		dev_warn(dmadev->ddev.dev, "channel did not stop\n");
		pm_runtime_mark_last_busy(dmadev->ddev.dev);
		pm_runtime_put_autosuspend(dmadev->ddev.dev);

		}

		static int hidma_remove(struct platform_device *pdev)
		{
		struct hidma_dev *dmadev = platform_get_drvdata(pdev);
		@@ -908,6 +922,7 @@ MODULE_DEVICE_TABLE(of, hidma_match);
		static struct platform_driver hidma_driver = {
		.probe = hidma_probe,
		.remove = hidma_remove,
		.shutdown = hidma_shutdown,
		.driver = {
		.name = "hidma",
		.of_match_table = hidma_match,

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