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03d70617b8
On PowerPC processors with non-coherent cache architectures the DMA subsystem calls invalidate_dcache_range() before performing a DMA read operation. If the address and length of the DMA buffer are not aligned to a cache-line boundary this can result in memory outside of the DMA buffer being invalidated in the cache. If this memory has an uncommitted store then the data will be lost and a subsequent read of that address will result in an old value being returned from main memory. Only when the DMA buffer starts on a cache-line boundary and is an exact mutiple of the cache-line size can invalidate_dcache_range() be called, otherwise flush_dcache_range() must be called. flush_dcache_range() will first flush uncommitted writes, and then invalidate the cache. Signed-off-by: Andrew Lewis <andrew-lewis at netspace.net.au> Signed-off-by: Paul Mackerras <paulus@samba.org> |
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| alloc.c | ||
| checksum_32.S | ||
| checksum_64.S | ||
| code-patching.c | ||
| copy_32.S | ||
| copypage_64.S | ||
| copyuser_64.S | ||
| crtsavres.S | ||
| devres.c | ||
| div64.S | ||
| dma-noncoherent.c | ||
| feature-fixups-test.S | ||
| feature-fixups.c | ||
| locks.c | ||
| Makefile | ||
| mem_64.S | ||
| memcpy_64.S | ||
| rheap.c | ||
| sstep.c | ||
| string.S | ||
| usercopy_64.c | ||