Comtrol eCos - Manual (Page 293)

Chapter 9. HAL Interfaces
HAL_XCACHE_SETS
Defines the number of sets in the cache, and is calculated from the previous values.
Global Cache Control
HAL_XCACHE_ENABLE()
HAL_XCACHE_DISABLE()
HAL_XCACHE_INVALIDATE_ALL()
HAL_XCACHE_SYNC()
HAL_XCACHE_BURST_SIZE( size )
HAL_DCACHE_WRITE_MODE( mode )
HAL_XCACHE_LOCK( base, size )
HAL_XCACHE_UNLOCK( base, size )
HAL_XCACHE_UNLOCK_ALL()
These macros affect the state of the entire cache, or a large part of it.
HAL_XCACHE_ENABLE() and HAL_XCACHE_DISABLE()
Enable and disable the cache.
HAL_XCACHE_INVALIDATE_ALL()
Causes the entire contents of the cache to be invalidated. Depending on the hardware, this may
require the cache to be disabled during the invalidation process. If so, the implementation must use
HAL_XCACHE_IS_ENABLED() to save and restore the previous state.
Note: If this macro is called after HAL_XCACHE_SYNC() with the intention of clearing the cache (invalidating
the cache after writing dirty data back to memory), you must prevent interrupts from happening between
the two calls:
...
HAL_DISABLE_INTERRUPTS(old);
HAL_XCACHE_SYNC();
HAL_XCACHE_INVALIDATE_ALL();
HAL_RESTORE_INTERRUPTS(old);
...
Since the operation may take a very long time, real-time responsiveness could be affected, so only do this
when it is absolutely required and you know the delay will not interfere with the operation of drivers or the
application.
HAL_XCACHE_SYNC()
Causes the contents of the cache to be brought into synchronization with the contents of memory. In some
implementations this may be equivalent to HAL_XCACHE_INVALIDATE_ALL() .
189