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Diffstat (limited to 'arch/arm/mach-tegra/timer.c')
-rw-r--r--arch/arm/mach-tegra/timer.c42
1 files changed, 16 insertions, 26 deletions
diff --git a/arch/arm/mach-tegra/timer.c b/arch/arm/mach-tegra/timer.c
index e2272d263a8..1d1acda4f3e 100644
--- a/arch/arm/mach-tegra/timer.c
+++ b/arch/arm/mach-tegra/timer.c
@@ -19,7 +19,6 @@
#include <linux/init.h>
#include <linux/err.h>
-#include <linux/sched.h>
#include <linux/time.h>
#include <linux/interrupt.h>
#include <linux/irq.h>
@@ -106,25 +105,9 @@ static struct clock_event_device tegra_clockevent = {
.set_mode = tegra_timer_set_mode,
};
-static DEFINE_CLOCK_DATA(cd);
-
-/*
- * Constants generated by clocks_calc_mult_shift(m, s, 1MHz, NSEC_PER_SEC, 60).
- * This gives a resolution of about 1us and a wrap period of about 1h11min.
- */
-#define SC_MULT 4194304000u
-#define SC_SHIFT 22
-
-unsigned long long notrace sched_clock(void)
+static u32 notrace tegra_read_sched_clock(void)
{
- u32 cyc = timer_readl(TIMERUS_CNTR_1US);
- return cyc_to_fixed_sched_clock(&cd, cyc, (u32)~0, SC_MULT, SC_SHIFT);
-}
-
-static void notrace tegra_update_sched_clock(void)
-{
- u32 cyc = timer_readl(TIMERUS_CNTR_1US);
- update_sched_clock(&cd, cyc, (u32)~0);
+ return timer_readl(TIMERUS_CNTR_1US);
}
/*
@@ -182,20 +165,28 @@ static struct irqaction tegra_timer_irq = {
static void __init tegra_init_timer(void)
{
struct clk *clk;
- unsigned long rate = clk_measure_input_freq();
+ unsigned long rate;
int ret;
clk = clk_get_sys("timer", NULL);
- BUG_ON(IS_ERR(clk));
- clk_enable(clk);
+ if (IS_ERR(clk)) {
+ pr_warn("Unable to get timer clock."
+ " Assuming 12Mhz input clock.\n");
+ rate = 12000000;
+ } else {
+ clk_enable(clk);
+ rate = clk_get_rate(clk);
+ }
/*
* rtc registers are used by read_persistent_clock, keep the rtc clock
* enabled
*/
clk = clk_get_sys("rtc-tegra", NULL);
- BUG_ON(IS_ERR(clk));
- clk_enable(clk);
+ if (IS_ERR(clk))
+ pr_warn("Unable to get rtc-tegra clock\n");
+ else
+ clk_enable(clk);
#ifdef CONFIG_HAVE_ARM_TWD
twd_base = IO_ADDRESS(TEGRA_ARM_PERIF_BASE + 0x600);
@@ -218,8 +209,7 @@ static void __init tegra_init_timer(void)
WARN(1, "Unknown clock rate");
}
- init_fixed_sched_clock(&cd, tegra_update_sched_clock, 32,
- 1000000, SC_MULT, SC_SHIFT);
+ setup_sched_clock(tegra_read_sched_clock, 32, 1000000);
if (clocksource_mmio_init(timer_reg_base + TIMERUS_CNTR_1US,
"timer_us", 1000000, 300, 32, clocksource_mmio_readl_up)) {