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openrisc: remove the sync_single_for_cpu DMA operation 

openrisc does all the required cache maintainance at dma map time, and none
at unmap time.  It thus has to implement sync_single_for_device to match
the map cace for buffer reuse, but there is no point in doing another
invalidation in the sync_single_cpu_case, which in terms of cache
maintainance is equivalent to the unmap case.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Stafford Horne <shorne@gmail.com>
hifive-unleashed-5.1
Christoph Hellwig 2018-07-19 06:02:29 -07:00 committed by Stafford Horne
parent 1e4b044d22
commit 1902cbcc8b
1 changed files with 0 additions and 15 deletions
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15
arch/openrisc/kernel/dma.c
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@ -208,20 +208,6 @@ or1k_unmap_sg(struct device *dev, struct scatterlist *sg,
}
}
static void
or1k_sync_single_for_cpu(struct device *dev,
dma_addr_t dma_handle, size_t size,
enum dma_data_direction dir)
{
unsigned long cl;
dma_addr_t addr = dma_handle;
struct cpuinfo_or1k *cpuinfo = &cpuinfo_or1k[smp_processor_id()];
/* Invalidate the dcache for the requested range */
for (cl = addr; cl < addr + size; cl += cpuinfo->dcache_block_size)
mtspr(SPR_DCBIR, cl);
}
static void
or1k_sync_single_for_device(struct device *dev,
dma_addr_t dma_handle, size_t size,
@ -243,7 +229,6 @@ const struct dma_map_ops or1k_dma_map_ops = {
.unmap_page = or1k_unmap_page,
.map_sg = or1k_map_sg,
.unmap_sg = or1k_unmap_sg,
.sync_single_for_cpu = or1k_sync_single_for_cpu,
.sync_single_for_device = or1k_sync_single_for_device,
};
EXPORT_SYMBOL(or1k_dma_map_ops);