kernel-ark/arch/blackfin/mach-common/cache.S
Mike Frysinger 39e96c8835 Blackfin arch: fix bug - dmacopy test case fail on all platform
The cache code I added flushes 1 line too little if the start address is
not aligned to the cache size. Cache align the start address so that when
we straddle cache aligns, we get the right count.

Signed-off-by: Mike Frysinger <vapier.adi@gmail.com>
Signed-off-by: Bryan Wu <cooloney@kernel.org>
2008-11-18 17:48:22 +08:00

96 lines
2.4 KiB
ArmAsm

/*
* Blackfin cache control code
*
* Copyright 2004-2008 Analog Devices Inc.
*
* Enter bugs at http://blackfin.uclinux.org/
*
* Licensed under the GPL-2 or later.
*/
#include <linux/linkage.h>
#include <asm/blackfin.h>
#include <asm/cache.h>
#include <asm/page.h>
.text
/* Since all L1 caches work the same way, we use the same method for flushing
* them. Only the actual flush instruction differs. We write this in asm as
* GCC can be hard to coax into writing nice hardware loops.
*
* Also, we assume the following register setup:
* R0 = start address
* R1 = end address
*/
.macro do_flush flushins:req optflushins optnopins label
R2 = -L1_CACHE_BYTES;
/* start = (start & -L1_CACHE_BYTES) */
R0 = R0 & R2;
/* end = ((end - 1) & -L1_CACHE_BYTES) + L1_CACHE_BYTES; */
R1 += -1;
R1 = R1 & R2;
R1 += L1_CACHE_BYTES;
/* count = (end - start) >> L1_CACHE_SHIFT */
R2 = R1 - R0;
R2 >>= L1_CACHE_SHIFT;
P1 = R2;
.ifnb \label
\label :
.endif
P0 = R0;
LSETUP (1f, 2f) LC1 = P1;
1:
.ifnb \optflushins
\optflushins [P0];
.endif
.ifb \optnopins
2:
.endif
\flushins [P0++];
.ifnb \optnopins
2: \optnopins;
.endif
RTS;
.endm
/* Invalidate all instruction cache lines assocoiated with this memory area */
ENTRY(_blackfin_icache_flush_range)
do_flush IFLUSH, , nop
ENDPROC(_blackfin_icache_flush_range)
/* Flush all cache lines assocoiated with this area of memory. */
ENTRY(_blackfin_icache_dcache_flush_range)
do_flush FLUSH, IFLUSH
ENDPROC(_blackfin_icache_dcache_flush_range)
/* Throw away all D-cached data in specified region without any obligation to
* write them back. Since the Blackfin ISA does not have an "invalidate"
* instruction, we use flush/invalidate. Perhaps as a speed optimization we
* could bang on the DTEST MMRs ...
*/
ENTRY(_blackfin_dcache_invalidate_range)
do_flush FLUSHINV
ENDPROC(_blackfin_dcache_invalidate_range)
/* Flush all data cache lines assocoiated with this memory area */
ENTRY(_blackfin_dcache_flush_range)
do_flush FLUSH, , , .Ldfr
ENDPROC(_blackfin_dcache_flush_range)
/* Our headers convert the page structure to an address, so just need to flush
* its contents like normal. We know the start address is page aligned (which
* greater than our cache alignment), as is the end address. So just jump into
* the middle of the dcache flush function.
*/
ENTRY(_blackfin_dflush_page)
P1 = 1 << (PAGE_SHIFT - L1_CACHE_SHIFT);
jump .Ldfr;
ENDPROC(_blackfin_dflush_page)