aboutsummaryrefslogtreecommitdiff
path: root/lib_mips/time.c
diff options
context:
space:
mode:
Diffstat (limited to 'lib_mips/time.c')
-rw-r--r--lib_mips/time.c57
1 files changed, 28 insertions, 29 deletions
diff --git a/lib_mips/time.c b/lib_mips/time.c
index cd8dc721e2b..1e9278996e5 100644
--- a/lib_mips/time.c
+++ b/lib_mips/time.c
@@ -22,26 +22,12 @@
*/
#include <common.h>
+#include <asm/mipsregs.h>
+static unsigned long timestamp;
-static inline void mips_compare_set(u32 v)
-{
- asm volatile ("mtc0 %0, $11" : : "r" (v));
-}
-
-static inline void mips_count_set(u32 v)
-{
- asm volatile ("mtc0 %0, $9" : : "r" (v));
-}
-
-
-static inline u32 mips_count_get(void)
-{
- u32 count;
-
- asm volatile ("mfc0 %0, $9" : "=r" (count) :);
- return count;
-}
+/* how many counter cycles in a jiffy */
+#define CYCLES_PER_JIFFY (CFG_MIPS_TIMER_FREQ + CFG_HZ / 2) / CFG_HZ
/*
* timer without interrupts
@@ -49,34 +35,47 @@ static inline u32 mips_count_get(void)
int timer_init(void)
{
- mips_compare_set(0);
- mips_count_set(0);
+ /* Set up the timer for the first expiration. */
+ timestamp = 0;
+ write_c0_compare(read_c0_count() + CYCLES_PER_JIFFY);
return 0;
}
void reset_timer(void)
{
- mips_count_set(0);
+ timestamp = 0;
+ write_c0_compare(read_c0_count() + CYCLES_PER_JIFFY);
}
ulong get_timer(ulong base)
{
- return mips_count_get() - base;
+ unsigned int count;
+ unsigned int expirelo = read_c0_compare();
+
+ /* Check to see if we have missed any timestamps. */
+ count = read_c0_count();
+ while ((count - expirelo) < 0x7fffffff) {
+ expirelo += CYCLES_PER_JIFFY;
+ timestamp++;
+ }
+ write_c0_compare(expirelo);
+
+ return (timestamp - base);
}
void set_timer(ulong t)
{
- mips_count_set(t);
+ timestamp = t;
+ write_c0_compare(read_c0_count() + CYCLES_PER_JIFFY);
}
-void udelay (unsigned long usec)
+void udelay(unsigned long usec)
{
- ulong tmo;
- ulong start = get_timer(0);
+ unsigned int tmo;
- tmo = usec * (CFG_HZ / 1000000);
- while ((ulong)((mips_count_get() - start)) < tmo)
+ tmo = read_c0_count() + (usec * (CFG_MIPS_TIMER_FREQ / 1000000));
+ while ((tmo - read_c0_count()) < 0x7fffffff)
/*NOP*/;
}
@@ -86,7 +85,7 @@ void udelay (unsigned long usec)
*/
unsigned long long get_ticks(void)
{
- return mips_count_get();
+ return get_timer(0);
}
/*