diff options
author | Jim Quinlan <james.quinlan@broadcom.com> | 2020-09-17 19:43:40 +0300 |
---|---|---|
committer | Christoph Hellwig <hch@lst.de> | 2020-09-17 19:43:56 +0300 |
commit | e0d072782c734d27f5af062c62266f2598f68542 (patch) | |
tree | f259e9eaab55ae8ffedaea07a19e8f147dcceb9a /include/linux/device.h | |
parent | 6eb0233ec2d0df288fe8515d5b0b2b15562e05bb (diff) | |
download | linux-e0d072782c734d27f5af062c62266f2598f68542.tar.xz |
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/device.h')
-rw-r--r-- | include/linux/device.h | 4 |
1 files changed, 2 insertions, 2 deletions
diff --git a/include/linux/device.h b/include/linux/device.h index ca18da4768e3..1c78621fc3c0 100644 --- a/include/linux/device.h +++ b/include/linux/device.h @@ -466,7 +466,7 @@ struct dev_links_info { * such descriptors. * @bus_dma_limit: Limit of an upstream bridge or bus which imposes a smaller * DMA limit than the device itself supports. - * @dma_pfn_offset: offset of DMA memory range relatively of RAM + * @dma_range_map: map for DMA memory ranges relative to that of RAM * @dma_parms: A low level driver may set these to teach IOMMU code about * segment limitations. * @dma_pools: Dma pools (if dma'ble device). @@ -561,7 +561,7 @@ struct device { 64 bit addresses for consistent allocations such descriptors. */ u64 bus_dma_limit; /* upstream dma constraint */ - unsigned long dma_pfn_offset; + const struct bus_dma_region *dma_range_map; struct device_dma_parameters *dma_parms; |