ARM: OMAP: TimerMPU: Remove unused cycles-to-nsec conversions

[linux-2.6-omap-h63xx.git] / arch / arm / mach-omap1 / time.c

diff --git a/arch/arm/mach-omap1/time.c b/arch/arm/mach-omap1/time.c
index 237651ebae5da555be9e346b36f154400d9acaa7..f6cf2b7e52becb2923ecb80db99f043a2bd48643 100644 (file)
--- a/arch/arm/mach-omap1/time.c
+++ b/arch/arm/mach-omap1/time.c
@@ -56,37 +56,6 @@
 #define OMAP_MPU_TIMER_BASE            OMAP_MPU_TIMER1_BASE
 #define OMAP_MPU_TIMER_OFFSET          0x100
 
-/* cycles to nsec conversions taken from arch/i386/kernel/timers/timer_tsc.c,
- * converted to use kHz by Kevin Hilman */
-/* convert from cycles(64bits) => nanoseconds (64bits)
- *  basic equation:
- *             ns = cycles / (freq / ns_per_sec)
- *             ns = cycles * (ns_per_sec / freq)
- *             ns = cycles * (10^9 / (cpu_khz * 10^3))
- *             ns = cycles * (10^6 / cpu_khz)
- *
- *     Then we use scaling math (suggested by george at mvista.com) to get:
- *             ns = cycles * (10^6 * SC / cpu_khz / SC
- *             ns = cycles * cyc2ns_scale / SC
- *
- *     And since SC is a constant power of two, we can convert the div
- *  into a shift.
- *                     -johnstul at us.ibm.com "math is hard, lets go shopping!"
- */
-static unsigned long cyc2ns_scale;
-#define CYC2NS_SCALE_FACTOR 10 /* 2^10, carefully chosen */
-
-static inline void set_cyc2ns_scale(unsigned long cpu_khz)
-{
-       cyc2ns_scale = (1000000 << CYC2NS_SCALE_FACTOR)/cpu_khz;
-}
-
-static inline unsigned long long cycles_2_ns(unsigned long long cyc)
-{
-       return (cyc * cyc2ns_scale) >> CYC2NS_SCALE_FACTOR;
-}
-
-
 typedef struct {
        u32 cntl;                       /* CNTL_TIMER, R/W */
        u32 load_tim;                   /* LOAD_TIM,   W */
@@ -132,13 +101,20 @@ static inline void omap_mpu_timer_start(int nr, unsigned long load_val,
        timer->cntl = timerflags;
 }
 
+static inline void omap_mpu_timer_stop(int nr)
+{
+       volatile omap_mpu_timer_regs_t* timer = omap_mpu_timer_base(nr);
+
+       timer->cntl &= ~MPU_TIMER_ST;
+}
+
 /*
  * ---------------------------------------------------------------------------
  * MPU timer 1 ... count down to zero, interrupt, reload
  * ---------------------------------------------------------------------------
  */
 static int omap_mpu_set_next_event(unsigned long cycles,
-                                   struct clock_event_device *evt)
+                                  struct clock_event_device *evt)
 {
        omap_mpu_timer_start(0, cycles, 0);
        return 0;
@@ -152,6 +128,7 @@ static void omap_mpu_set_mode(enum clock_event_mode mode,
                omap_mpu_set_autoreset(0);
                break;
        case CLOCK_EVT_MODE_ONESHOT:
+               omap_mpu_timer_stop(0);
                omap_mpu_remove_autoreset(0);
                break;
        case CLOCK_EVT_MODE_UNUSED:
@@ -163,7 +140,7 @@ static void omap_mpu_set_mode(enum clock_event_mode mode,
 
 static struct clock_event_device clockevent_mpu_timer1 = {
        .name           = "mpu_timer1",
-       .features       = CLOCK_EVT_FEAT_PERIODIC, CLOCK_EVT_FEAT_ONESHOT,
+       .features       = CLOCK_EVT_FEAT_PERIODIC | CLOCK_EVT_FEAT_ONESHOT,
        .shift          = 32,
        .set_next_event = omap_mpu_set_next_event,
        .set_mode       = omap_mpu_set_mode,
@@ -186,8 +163,6 @@ static struct irqaction omap_mpu_timer1_irq = {
 
 static __init void omap_init_mpu_timer(unsigned long rate)
 {
-       set_cyc2ns_scale(rate / 1000);
-
        setup_irq(INT_TIMER1, &omap_mpu_timer1_irq);
        omap_mpu_timer_start(0, (rate / HZ) - 1, 1);