diff options
| author | Jim Quinlan <james.quinlan@broadcom.com> | 2020-09-17 18:43:40 +0200 |
|---|---|---|
| committer | Christoph Hellwig <hch@lst.de> | 2020-09-17 18:43:56 +0200 |
| commit | e0d072782c734d27f5af062c62266f2598f68542 (patch) | |
| tree | f259e9eaab55ae8ffedaea07a19e8f147dcceb9a /include/linux/dma-mapping.h | |
| parent | 6eb0233ec2d0df288fe8515d5b0b2b15562e05bb (diff) | |
dma-mapping: introduce DMA range map, supplanting dma_pfn_offset
The new field 'dma_range_map' in struct device is used to facilitate the
use of single or multiple offsets between mapping regions of cpu addrs and
dma addrs. It subsumes the role of "dev->dma_pfn_offset" which was only
capable of holding a single uniform offset and had no region bounds
checking.
The function of_dma_get_range() has been modified so that it takes a single
argument -- the device node -- and returns a map, NULL, or an error code.
The map is an array that holds the information regarding the DMA regions.
Each range entry contains the address offset, the cpu_start address, the
dma_start address, and the size of the region.
of_dma_configure() is the typical manner to set range offsets but there are
a number of ad hoc assignments to "dev->dma_pfn_offset" in the kernel
driver code. These cases now invoke the function
dma_direct_set_offset(dev, cpu_addr, dma_addr, size).
Signed-off-by: Jim Quinlan <james.quinlan@broadcom.com>
[hch: various interface cleanups]
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Mathieu Poirier <mathieu.poirier@linaro.org>
Tested-by: Mathieu Poirier <mathieu.poirier@linaro.org>
Tested-by: Nathan Chancellor <natechancellor@gmail.com>
Diffstat (limited to 'include/linux/dma-mapping.h')
| -rw-r--r-- | include/linux/dma-mapping.h | 9 |
1 files changed, 8 insertions, 1 deletions
diff --git a/include/linux/dma-mapping.h b/include/linux/dma-mapping.h index df0bff2ea750..bb138ac6f5e6 100644 --- a/include/linux/dma-mapping.h +++ b/include/linux/dma-mapping.h @@ -730,4 +730,11 @@ static inline int dma_mmap_wc(struct device *dev, #define dma_unmap_len_set(PTR, LEN_NAME, VAL) do { } while (0) #endif -#endif +/* + * Legacy interface to set up the dma offset map. Drivers really should not + * actually use it, but we have a few legacy cases left. + */ +int dma_direct_set_offset(struct device *dev, phys_addr_t cpu_start, + dma_addr_t dma_start, u64 size); + +#endif /* _LINUX_DMA_MAPPING_H */ |