From c04ac679c6b86e4e36fbb675c6c061b4091f5810 Mon Sep 17 00:00:00 2001 From: Lorenzo Pieralisi Date: Mon, 7 Aug 2017 11:29:48 +0100 Subject: ACPI: Introduce DMA ranges parsing Some devices have limited addressing capabilities and cannot reference the whole memory address space while carrying out DMA operations (eg some devices with bus address bits range smaller than system bus - which prevents them from using bus addresses that are otherwise valid for the system). The ACPI _DMA object allows bus devices to define the DMA window that is actually addressable by devices that sit upstream the bus, therefore providing a means to parse and initialize the devices DMA masks and addressable DMA range size. By relying on the generic ACPI kernel layer to retrieve and parse resources, introduce ACPI core code to parse the _DMA object. Signed-off-by: Lorenzo Pieralisi Tested-by: Nate Watterson Signed-off-by: Rafael J. Wysocki --- include/linux/acpi.h | 8 ++++++++ 1 file changed, 8 insertions(+) (limited to 'include/linux/acpi.h') diff --git a/include/linux/acpi.h b/include/linux/acpi.h index c749eef1daa1..a5eaff9f2c6d 100644 --- a/include/linux/acpi.h +++ b/include/linux/acpi.h @@ -427,6 +427,8 @@ void acpi_dev_free_resource_list(struct list_head *list); int acpi_dev_get_resources(struct acpi_device *adev, struct list_head *list, int (*preproc)(struct acpi_resource *, void *), void *preproc_data); +int acpi_dev_get_dma_resources(struct acpi_device *adev, + struct list_head *list); int acpi_dev_filter_resource_type(struct acpi_resource *ares, unsigned long types); @@ -774,6 +776,12 @@ static inline enum dev_dma_attr acpi_get_dma_attr(struct acpi_device *adev) return DEV_DMA_NOT_SUPPORTED; } +static inline int acpi_dma_get_range(struct device *dev, u64 *dma_addr, + u64 *offset, u64 *size) +{ + return -ENODEV; +} + static inline int acpi_dma_configure(struct device *dev, enum dev_dma_attr attr) { -- cgit v1.2.3-59-g8ed1b