MTD/CFI: flash_read64 is defined a weak function (for SPARC)
SPARC has implemented __raw_readq, it reads 64-bit from any 32-bit address.
SPARC CPUs implement flash_read64 which calls __raw_readq.
For current SPARC architectures (LEON2 and LEON3) each read from the
FLASH must lead to a cache miss. This is because FLASH can not be set
non-cacheable since program code resides there, and alternatively disabling
cache is poor from performance view, or doing a cache flush between each
read is even poorer.
Forcing a cache miss on a SPARC is done by a special instruction "lda" -
load alternative space, the alternative space number (ASI) is processor
implementation spcific and can be found by including <asm/processor.h>.
Signed-off-by: NDaniel Hellstrom <daniel@gaisler.com>
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