From b84f196d963c3159329f72ca1913b08679004a43 Mon Sep 17 00:00:00 2001 From: "Suthikulpanit, Suravee" Date: Wed, 28 Oct 2015 15:50:48 -0700 Subject: ACPI: Adding DMA Attribute APIs for ACPI Device Adding acpi_get_dma_attr() to query DMA attributes of ACPI devices. It returns the enum dev_dma_attr, which communicates DMA information more clearly. This API replaces the acpi_check_dma(), which will be removed in subsequent patch. This patch also provides a convenient function, acpi_dma_supported(), to check DMA support of the specified ACPI device. Signed-off-by: Suravee Suthikulpanit Acked-by: Bjorn Helgaas Reviewed-by: Hanjun Guo Signed-off-by: Rafael J. Wysocki --- drivers/acpi/scan.c | 42 ++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 42 insertions(+) (limited to 'drivers/acpi') diff --git a/drivers/acpi/scan.c b/drivers/acpi/scan.c index d1ce377db3e9..ed3d76fadccf 100644 --- a/drivers/acpi/scan.c +++ b/drivers/acpi/scan.c @@ -1308,6 +1308,48 @@ void acpi_free_pnp_ids(struct acpi_device_pnp *pnp) kfree(pnp->unique_id); } +/** + * acpi_dma_supported - Check DMA support for the specified device. + * @adev: The pointer to acpi device + * + * Return false if DMA is not supported. Otherwise, return true + */ +bool acpi_dma_supported(struct acpi_device *adev) +{ + if (!adev) + return false; + + if (adev->flags.cca_seen) + return true; + + /* + * Per ACPI 6.0 sec 6.2.17, assume devices can do cache-coherent + * DMA on "Intel platforms". Presumably that includes all x86 and + * ia64, and other arches will set CONFIG_ACPI_CCA_REQUIRED=y. + */ + if (!IS_ENABLED(CONFIG_ACPI_CCA_REQUIRED)) + return true; + + return false; +} + +/** + * acpi_get_dma_attr - Check the supported DMA attr for the specified device. + * @adev: The pointer to acpi device + * + * Return enum dev_dma_attr. + */ +enum dev_dma_attr acpi_get_dma_attr(struct acpi_device *adev) +{ + if (!acpi_dma_supported(adev)) + return DEV_DMA_NOT_SUPPORTED; + + if (adev->flags.coherent_dma) + return DEV_DMA_COHERENT; + else + return DEV_DMA_NON_COHERENT; +} + static void acpi_init_coherency(struct acpi_device *adev) { unsigned long long cca = 0; -- cgit v1.2.1 From 1831eff876bd0bb8d64e9965a7ff47486c9a3ecd Mon Sep 17 00:00:00 2001 From: "Suthikulpanit, Suravee" Date: Wed, 28 Oct 2015 15:50:50 -0700 Subject: device property: ACPI: Make use of the new DMA Attribute APIs Now that we have the new DMA attribute APIs, we can replace the older acpi_check_dma() and device_dma_is_coherent(). Signed-off-by: Suravee Suthikulpanit Acked-by: Bjorn Helgaas Reviewed-by: Hanjun Guo Signed-off-by: Rafael J. Wysocki --- drivers/acpi/acpi_platform.c | 7 ++++++- drivers/acpi/glue.c | 8 +++++--- 2 files changed, 11 insertions(+), 4 deletions(-) (limited to 'drivers/acpi') diff --git a/drivers/acpi/acpi_platform.c b/drivers/acpi/acpi_platform.c index 06a67d5f2846..296b7a14893a 100644 --- a/drivers/acpi/acpi_platform.c +++ b/drivers/acpi/acpi_platform.c @@ -103,7 +103,12 @@ struct platform_device *acpi_create_platform_device(struct acpi_device *adev) pdevinfo.res = resources; pdevinfo.num_res = count; pdevinfo.fwnode = acpi_fwnode_handle(adev); - pdevinfo.dma_mask = acpi_check_dma(adev, NULL) ? DMA_BIT_MASK(32) : 0; + + if (acpi_dma_supported(adev)) + pdevinfo.dma_mask = DMA_BIT_MASK(32); + else + pdevinfo.dma_mask = 0; + pdev = platform_device_register_full(&pdevinfo); if (IS_ERR(pdev)) dev_err(&adev->dev, "platform device creation failed: %ld\n", diff --git a/drivers/acpi/glue.c b/drivers/acpi/glue.c index b9657af751d1..a66e77676b8a 100644 --- a/drivers/acpi/glue.c +++ b/drivers/acpi/glue.c @@ -168,7 +168,7 @@ int acpi_bind_one(struct device *dev, struct acpi_device *acpi_dev) struct list_head *physnode_list; unsigned int node_id; int retval = -EINVAL; - bool coherent; + enum dev_dma_attr attr; if (has_acpi_companion(dev)) { if (acpi_dev) { @@ -225,8 +225,10 @@ int acpi_bind_one(struct device *dev, struct acpi_device *acpi_dev) if (!has_acpi_companion(dev)) ACPI_COMPANION_SET(dev, acpi_dev); - if (acpi_check_dma(acpi_dev, &coherent)) - arch_setup_dma_ops(dev, 0, 0, NULL, coherent); + attr = acpi_get_dma_attr(acpi_dev); + if (attr != DEV_DMA_NOT_SUPPORTED) + arch_setup_dma_ops(dev, 0, 0, NULL, + attr == DEV_DMA_COHERENT); acpi_physnode_link_name(physical_node_name, node_id); retval = sysfs_create_link(&acpi_dev->dev.kobj, &dev->kobj, -- cgit v1.2.1