arch: nios2: Add _nios2_dcache_flush_no_writeback() routine

Add _nios2_dcache_flush_no_writeback() routine to invalidate
cache contents of address provided.

This routine is ported from Altera Nios-II SDK v17.

Signed-off-by: Ramakrishna Pallala <ramakrishna.pallala@intel.com>
This commit is contained in:
Ramakrishna Pallala 2018-04-03 10:23:36 +05:30 committed by Anas Nashif
commit 4073db79d7
2 changed files with 32 additions and 0 deletions

View file

@ -60,3 +60,33 @@ void _nios2_dcache_flush_all(void)
}
}
#endif
/*
* _nios2_dcache_flush_no_writeback() is called to flush the data cache for a
* memory region of length "len" bytes, starting at address "start".
*
* Any dirty lines in the data cache are NOT written back to memory.
* Make sure you really want this behavior. If you aren't 100% sure,
* use the _nios2_dcache_flush() routine instead.
*/
#if ALT_CPU_DCACHE_SIZE > 0
void _nios2_dcache_flush_no_writeback(void *start, u32_t len)
{
u8_t *i;
u8_t *end = ((char *) start) + len;
for (i = start; i < end; i += ALT_CPU_DCACHE_LINE_SIZE) {
__asm__ volatile ("initda (%0)" :: "r" (i));
}
/*
* For an unaligned flush request, we've got one more line left.
* Note that this is dependent on ALT_CPU_DCACHE_LINE_SIZE to be a
* multiple of 2 (which it always is).
*/
if (((u32_t) start) & (ALT_CPU_DCACHE_LINE_SIZE - 1)) {
__asm__ volatile ("initda (%0)" :: "r" (i));
}
}
#endif

View file

@ -60,8 +60,10 @@ void _nios2_icache_flush_all(void);
#if ALT_CPU_DCACHE_SIZE > 0
void _nios2_dcache_flush_all(void);
void _nios2_dcache_flush_no_writeback(void *start, u32_t len);
#else
#define _nios2_dcache_flush_all() do { } while (0)
#define _nios2_dcache_flush_no_writeback(x, y) do { } while (0)
#endif
#endif /* _ASMLANGUAGE */