On DT based systems, the of_dma_configure() API implements DMA configuration for a given device. On ACPI systems an API equivalent to of_dma_configure() is missing which implies that it is currently not possible to set-up DMA operations for devices through the ACPI generic kernel layer.
This patch fills the gap by introducing acpi_dma_configure/deconfigure() calls that for now are just wrappers around arch_setup_dma_ops() and arch_teardown_dma_ops() and also updates ACPI and PCI core code to use the newly introduced acpi_dma_configure/acpi_dma_deconfigure functions. The DMA range size passed to arch_setup_dma_ops() is sized according to the device coherent_dma_mask (starting at address 0x0), mirroring the DT probing path behaviour when a dma-ranges property is not provided for the device being probed; this changes the current arch_setup_dma_ops() call parameters in the ACPI probing case, but since arch_setup_dma_ops() is a NOP on all architectures but ARM/ARM64 this patch does not change the current kernel behaviour on them. Signed-off-by: Lorenzo Pieralisi <[email protected]> Acked-by: Bjorn Helgaas <[email protected]> [pci] Cc: Bjorn Helgaas <[email protected]> Cc: Robin Murphy <[email protected]> Cc: Tomasz Nowicki <[email protected]> Cc: Joerg Roedel <[email protected]> Cc: "Rafael J. Wysocki" <[email protected]> --- drivers/acpi/glue.c | 4 ++-- drivers/acpi/scan.c | 24 ++++++++++++++++++++++++ drivers/pci/probe.c | 3 +-- include/acpi/acpi_bus.h | 2 ++ include/linux/acpi.h | 5 +++++ 5 files changed, 34 insertions(+), 4 deletions(-) diff --git a/drivers/acpi/glue.c b/drivers/acpi/glue.c index 5ea5dc2..f8d6564 100644 --- a/drivers/acpi/glue.c +++ b/drivers/acpi/glue.c @@ -227,8 +227,7 @@ int acpi_bind_one(struct device *dev, struct acpi_device *acpi_dev) 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_dma_configure(dev, attr); acpi_physnode_link_name(physical_node_name, node_id); retval = sysfs_create_link(&acpi_dev->dev.kobj, &dev->kobj, @@ -251,6 +250,7 @@ int acpi_bind_one(struct device *dev, struct acpi_device *acpi_dev) return 0; err: + acpi_dma_deconfigure(dev); ACPI_COMPANION_SET(dev, NULL); put_device(dev); put_device(&acpi_dev->dev); diff --git a/drivers/acpi/scan.c b/drivers/acpi/scan.c index 5f28cf7..b4b9064 100644 --- a/drivers/acpi/scan.c +++ b/drivers/acpi/scan.c @@ -1358,6 +1358,30 @@ enum dev_dma_attr acpi_get_dma_attr(struct acpi_device *adev) return DEV_DMA_NON_COHERENT; } +/** + * acpi_dma_configure - Set-up DMA configuration for the device. + * @dev: The pointer to the device + * @attr: device dma attributes + */ +void acpi_dma_configure(struct device *dev, enum dev_dma_attr attr) +{ + /* + * Assume dma valid range starts at 0 and covers the whole + * coherent_dma_mask. + */ + arch_setup_dma_ops(dev, 0, dev->coherent_dma_mask + 1, NULL, + attr == DEV_DMA_COHERENT); +} + +/** + * acpi_dma_deconfigure - Tear-down DMA configuration for the device. + * @dev: The pointer to the device + */ +void acpi_dma_deconfigure(struct device *dev) +{ + arch_teardown_dma_ops(dev); +} + static void acpi_init_coherency(struct acpi_device *adev) { unsigned long long cca = 0; diff --git a/drivers/pci/probe.c b/drivers/pci/probe.c index 380d46d..7ef3933 100644 --- a/drivers/pci/probe.c +++ b/drivers/pci/probe.c @@ -1725,8 +1725,7 @@ static void pci_dma_configure(struct pci_dev *dev) if (attr == DEV_DMA_NOT_SUPPORTED) dev_warn(&dev->dev, "DMA not supported.\n"); else - arch_setup_dma_ops(&dev->dev, 0, 0, NULL, - attr == DEV_DMA_COHERENT); + acpi_dma_configure(&dev->dev, attr); } pci_put_host_bridge_device(bridge); diff --git a/include/acpi/acpi_bus.h b/include/acpi/acpi_bus.h index 788c6c35..8b5039a 100644 --- a/include/acpi/acpi_bus.h +++ b/include/acpi/acpi_bus.h @@ -566,6 +566,8 @@ struct acpi_pci_root { bool acpi_dma_supported(struct acpi_device *adev); enum dev_dma_attr acpi_get_dma_attr(struct acpi_device *adev); +void acpi_dma_configure(struct device *dev, enum dev_dma_attr attr); +void acpi_dma_deconfigure(struct device *dev); struct acpi_device *acpi_find_child_device(struct acpi_device *parent, u64 address, bool check_children); diff --git a/include/linux/acpi.h b/include/linux/acpi.h index 288fac5..135a452 100644 --- a/include/linux/acpi.h +++ b/include/linux/acpi.h @@ -676,6 +676,11 @@ static inline enum dev_dma_attr acpi_get_dma_attr(struct acpi_device *adev) return DEV_DMA_NOT_SUPPORTED; } +static inline void acpi_dma_configure(struct device *dev, + enum dev_dma_attr attr) { } + +static inline void acpi_dma_deconfigure(struct device *dev) { } + #define ACPI_PTR(_ptr) (NULL) #endif /* !CONFIG_ACPI */ -- 2.6.4
