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xtensa: cache inquiry and unaligned cache handling functions 

The existing xtensa cache handling functions work on page-aligned
memory regions.

These functions are needed for the s6000 dma engine which can work on
a byte-granularity.

Signed-off-by: Oskar Schirmer <os@emlix.com>
Cc: Johannes Weiner <jw@emlix.com>
Cc: Daniel Glockner <dg@emlix.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Chris Zankel <chris@zankel.net>
This commit is contained in:
Oskar Schirmer 2009-06-10 12:58:45 -07:00 committed by Chris Zankel
parent f234012f52
commit bd974240c9
1 changed files with 95 additions and 0 deletions
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95
arch/xtensa/include/asm/cacheflush.h
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@ -155,5 +155,100 @@ extern void copy_from_user_page(struct vm_area_struct*, struct page*,
#endif
#define XTENSA_CACHEBLK_LOG2 29
#define XTENSA_CACHEBLK_SIZE (1 << XTENSA_CACHEBLK_LOG2)
#define XTENSA_CACHEBLK_MASK (7 << XTENSA_CACHEBLK_LOG2)
#if XCHAL_HAVE_CACHEATTR
static inline u32 xtensa_get_cacheattr(void)
{
u32 r;
asm volatile(" rsr %0, CACHEATTR" : "=a"(r));
return r;
}
static inline u32 xtensa_get_dtlb1(u32 addr)
{
u32 r = addr & XTENSA_CACHEBLK_MASK;
return r | ((xtensa_get_cacheattr() >> (r >> (XTENSA_CACHEBLK_LOG2-2)))
& 0xF);
}
#else
static inline u32 xtensa_get_dtlb1(u32 addr)
{
u32 r;
asm volatile(" rdtlb1 %0, %1" : "=a"(r) : "a"(addr));
asm volatile(" dsync");
return r;
}
static inline u32 xtensa_get_cacheattr(void)
{
u32 r = 0;
u32 a = 0;
do {
a -= XTENSA_CACHEBLK_SIZE;
r = (r << 4) | (xtensa_get_dtlb1(a) & 0xF);
} while (a);
return r;
}
#endif
static inline int xtensa_need_flush_dma_source(u32 addr)
{
return (xtensa_get_dtlb1(addr) & ((1 << XCHAL_CA_BITS) - 1)) >= 4;
}
static inline int xtensa_need_invalidate_dma_destination(u32 addr)
{
return (xtensa_get_dtlb1(addr) & ((1 << XCHAL_CA_BITS) - 1)) != 2;
}
static inline void flush_dcache_unaligned(u32 addr, u32 size)
{
u32 cnt;
if (size) {
cnt = (size + ((XCHAL_DCACHE_LINESIZE - 1) & addr)
+ XCHAL_DCACHE_LINESIZE - 1) / XCHAL_DCACHE_LINESIZE;
while (cnt--) {
asm volatile(" dhwb %0, 0" : : "a"(addr));
addr += XCHAL_DCACHE_LINESIZE;
}
asm volatile(" dsync");
}
}
static inline void invalidate_dcache_unaligned(u32 addr, u32 size)
{
int cnt;
if (size) {
asm volatile(" dhwbi %0, 0 ;" : : "a"(addr));
cnt = (size + ((XCHAL_DCACHE_LINESIZE - 1) & addr)
- XCHAL_DCACHE_LINESIZE - 1) / XCHAL_DCACHE_LINESIZE;
while (cnt-- > 0) {
asm volatile(" dhi %0, %1" : : "a"(addr),
"n"(XCHAL_DCACHE_LINESIZE));
addr += XCHAL_DCACHE_LINESIZE;
}
asm volatile(" dhwbi %0, %1" : : "a"(addr),
"n"(XCHAL_DCACHE_LINESIZE));
asm volatile(" dsync");
}
}
static inline void flush_invalidate_dcache_unaligned(u32 addr, u32 size)
{
u32 cnt;
if (size) {
cnt = (size + ((XCHAL_DCACHE_LINESIZE - 1) & addr)
+ XCHAL_DCACHE_LINESIZE - 1) / XCHAL_DCACHE_LINESIZE;
while (cnt--) {
asm volatile(" dhwbi %0, 0" : : "a"(addr));
addr += XCHAL_DCACHE_LINESIZE;
}
asm volatile(" dsync");
}
}
#endif /* __KERNEL__ */
#endif /* _XTENSA_CACHEFLUSH_H */