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Diffstat (limited to 'arch/arm/cpu/arm926ejs/davinci')
-rw-r--r--arch/arm/cpu/arm926ejs/davinci/timer.c77
1 files changed, 28 insertions, 49 deletions
diff --git a/arch/arm/cpu/arm926ejs/davinci/timer.c b/arch/arm/cpu/arm926ejs/davinci/timer.c
index 9da7443..1c6fa4a 100644
--- a/arch/arm/cpu/arm926ejs/davinci/timer.c
+++ b/arch/arm/cpu/arm926ejs/davinci/timer.c
@@ -40,6 +40,8 @@
#include <common.h>
#include <asm/io.h>
+DECLARE_GLOBAL_DATA_PTR;
+
struct davinci_timer {
u_int32_t pid12;
u_int32_t emumgt;
@@ -57,11 +59,9 @@ struct davinci_timer {
static struct davinci_timer * const timer =
(struct davinci_timer *)CONFIG_SYS_TIMERBASE;
-#define TIMER_LOAD_VAL (CONFIG_SYS_HZ_CLOCK / CONFIG_SYS_HZ)
-#define TIM_CLK_DIV 16
+#define TIMER_LOAD_VAL 0xffffffff
-static ulong timestamp;
-static ulong lastinc;
+#define TIM_CLK_DIV 16
int timer_init(void)
{
@@ -71,72 +71,51 @@ int timer_init(void)
writel(0x06 | ((TIM_CLK_DIV - 1) << 8), &timer->tgcr);
writel(0x0, &timer->tim34);
writel(TIMER_LOAD_VAL, &timer->prd34);
- lastinc = 0;
- timestamp = 0;
writel(2 << 22, &timer->tcr);
+ gd->timer_rate_hz = CONFIG_SYS_HZ_CLOCK / TIM_CLK_DIV;
+ gd->timer_reset_value = 0;
return(0);
}
void reset_timer(void)
{
- writel(0x0, &timer->tcr);
- writel(0x0, &timer->tim34);
- lastinc = 0;
- timestamp = 0;
- writel(2 << 22, &timer->tcr);
+ gd->timer_reset_value = get_ticks();
}
-static ulong get_timer_raw(void)
+/*
+ * Get the current 64 bit timer tick count
+ */
+unsigned long long get_ticks(void)
{
- ulong now = readl(&timer->tim34);
-
- if (now >= lastinc) {
- /* normal mode */
- timestamp += now - lastinc;
- } else {
- /* overflow ... */
- timestamp += now + TIMER_LOAD_VAL - lastinc;
- }
- lastinc = now;
- return timestamp;
+ unsigned long now = readl(&timer->tim34);
+
+ /* increment tbu if tbl has rolled over */
+ if (now < gd->tbl)
+ gd->tbu++;
+ gd->tbl = now;
+
+ return (((unsigned long long)gd->tbu) << 32) | gd->tbl;
}
ulong get_timer(ulong base)
{
- return((get_timer_raw() / (TIMER_LOAD_VAL / TIM_CLK_DIV)) - base);
-}
+ unsigned long long timer_diff;
-void set_timer(ulong t)
-{
- timestamp = t;
+ timer_diff = get_ticks() - gd->timer_reset_value;
+
+ return (timer_diff / (gd->timer_rate_hz / CONFIG_SYS_HZ)) - base;
}
void __udelay(unsigned long usec)
{
- ulong tmo;
- ulong endtime;
- signed long diff;
-
- tmo = CONFIG_SYS_HZ_CLOCK / 1000;
- tmo *= usec;
- tmo /= (1000 * TIM_CLK_DIV);
-
- endtime = get_timer_raw() + tmo;
+ unsigned long long endtime;
- do {
- ulong now = get_timer_raw();
- diff = endtime - now;
- } while (diff >= 0);
-}
+ endtime = ((unsigned long long)usec * gd->timer_rate_hz) / 1000000UL;
+ endtime += get_ticks();
-/*
- * This function is derived from PowerPC code (read timebase as long long).
- * On ARM it just returns the timer value.
- */
-unsigned long long get_ticks(void)
-{
- return(get_timer(0));
+ while (get_ticks() < endtime)
+ ;
}
/*