Docs » Autodocs » exec.library » CachePostDMA
CachePostDMA - Take actions after to hardware DMA (V37)
CachePostDMA(vaddress,&length,flags)
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CachePostDMA(APTR,LONG *,ULONG);
Take all appropriate steps after Direct Memory Access (DMA). This
function is primarily intended for writers of DMA device drivers. The
action will depend on the CPU type installed, caching modes, and the
state of any Memory Management Unit (MMU) activity.
As implemented
68000 - Do nothing
68010 - Do nothing
68020 - Do nothing
68030 - Flush the data cache
68040 - Flush matching areas of the data cache
????? - External cache boards, Virtual Memory Systems, or
future hardware may patch this vector to best emulate
the intended behavior.
With a Bus-Snooping CPU, this function my end up
doing nothing.
address - Same as initially passed to CachePreDMA
length - Same as initially passed to CachePreDMA
flags - Values:
DMA_NoModify - If the area was not modified (and
thus there is no reason to flush the cache) set
this bit.
DMA_ReadFromRAM - Indicates that this DMA is a
read from RAM to the DMA device (ie - a write
to the hard drive) This flag is not required
but if used must match in both the PreDMA and
PostDMA calls. This flag *should* be used to
help the system provide the best performance.
This flag is safe in all versions of CachePostDMA()
"exec/execbase.i", CachePreDMA(), CacheClearU(), CacheClearE()
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