diff options
Diffstat (limited to 'frontend/pcnt.h')
| -rw-r--r-- | frontend/pcnt.h | 13 |
1 files changed, 13 insertions, 0 deletions
diff --git a/frontend/pcnt.h b/frontend/pcnt.h index 232ae07..3969aa4 100644 --- a/frontend/pcnt.h +++ b/frontend/pcnt.h @@ -83,6 +83,19 @@ static inline unsigned int pcnt_get(void) return val; } +static inline void pcnt_init(void) +{ +#ifdef __ARM_ARCH_7A__ + int v; + asm volatile("mrc p15, 0, %0, c9, c12, 0" : "=r"(v)); + v |= 5; // master enable, ccnt reset + v &= ~8; // ccnt divider 0 + asm volatile("mcr p15, 0, %0, c9, c12, 0" :: "r"(v)); + // enable cycle counter + asm volatile("mcr p15, 0, %0, c9, c12, 1" :: "r"(1<<31)); +#endif +} + #else #define pcnt_start(id) |