Instruction Overview
17-2
ADSP-BF53x/BF56x Blackfin Processor Programming Reference
to invalidate a buffer, but the instruction also performs a flush of data
marked as “dirty.” The
ITEST
and
DTEST
registers, which are described in
the
“Memory”
chapter, can also be used to directly invalidate a line in
cache. Buffers in source memory need to be invalidated when a DMA
channel is filling the buffer and data cache has been enabled and the
source memory has been defined as cacheable. By invalidating the
cache-lines associated with the buffer, “coherency” is maintained between
the contents stored in cache and the actual values in source memory.
When the buffer size is less than or equal in size to the actual cache on the
processor, it is better to use the
FLUSHINV
instruction in a loop to invali-
date the cache-lines. When the buffer is larger in size than the cache, it is
better to use the
DTEST
registers described in the
“Memory”
chapter to
invalidate the cache-lines.
The
IFLUSH
instruction is used to invalidate an instruction cache-line.
On the Blackfin processors, the cache-line size is 32 bytes.
Содержание ADSP-BF53x Blackfin
Страница 38: ...Conventions xxxviii ADSP BF53x BF56x Blackfin Processor Programming Reference...
Страница 134: ...System Reset and Powerup 3 18 ADSP BF53x BF56x Blackfin Processor Programming Reference...
Страница 324: ...Instruction Overview 7 20 ADSP BF53x BF56x Blackfin Processor Programming Reference...
Страница 486: ...Instruction Overview 13 28 ADSP BF53x BF56x Blackfin Processor Programming Reference...
Страница 512: ...Instruction Overview 14 26 ADSP BF53x BF56x Blackfin Processor Programming Reference...
Страница 604: ...Instruction Overview 15 92 ADSP BF53x BF56x Blackfin Processor Programming Reference...
Страница 688: ...Instruction Overview 18 48 ADSP BF53x BF56x Blackfin Processor Programming Reference...
Страница 742: ...Instruction Overview 19 54 ADSP BF53x BF56x Blackfin Processor Programming Reference...
Страница 752: ...Examples 20 10 ADSP BF53x BF56x Blackfin Processor Programming Reference...
Страница 780: ...Product Identification Register 21 28 ADSP BF53x BF56x Blackfin Processor Programming Reference...
Страница 790: ...ADSP BF535 Flags A 10 ADSP BF53x BF56x Blackfin Processor Programming Reference...
Страница 800: ...Performance Monitor Registers B 10 ADSP BF53x BF56x Blackfin Processor Programming Reference...
Страница 994: ...Instructions Listed By Operation Code C 194 ADSP BF53x BF56x Blackfin Processor Programming Reference...
Страница 1042: ...Index I 40 ADSP BF53x BF56x Blackfin Processor Programming Reference...