All Tegra SoCs have a freerunning microsecond counter which can be used as a
delay timer.
Signed-off-by: Peter De Schrijver <pdeschrij...@nvidia.com>
---
drivers/clocksource/tegra20_timer.c | 13 +++++++++++++
1 files changed, 13 insertions(+), 0 deletions(-)
diff --git a/drivers/clocksource/tegra20_timer.c
b/drivers/clocksource/tegra20_timer.c
index d1869f0..ed49a0b 100644
--- a/drivers/clocksource/tegra20_timer.c
+++ b/drivers/clocksource/tegra20_timer.c
@@ -28,6 +28,7 @@
#include <linux/of_irq.h>
#include <linux/sched_clock.h>
+#include <asm/delay.h>
#include <asm/mach/time.h>
#include <asm/smp_twd.h>
@@ -53,6 +54,8 @@ static void __iomem *rtc_base;
static struct timespec persistent_ts;
static u64 persistent_ms, last_persistent_ms;
+static struct delay_timer tegra_delay_timer;
+
#define timer_writel(value, reg) \
__raw_writel(value, timer_reg_base + (reg))
#define timer_readl(reg) \
@@ -139,6 +142,11 @@ static void tegra_read_persistent_clock(struct timespec
*ts)
*ts = *tsp;
}
+static unsigned long tegra_delay_timer_read_counter_long(void)
+{
+ return readl(timer_reg_base + TIMERUS_CNTR_1US);
+}
+
static irqreturn_t tegra_timer_interrupt(int irq, void *dev_id)
{
struct clock_event_device *evt = (struct clock_event_device *)dev_id;
@@ -206,6 +214,11 @@ static void __init tegra20_init_timer(struct device_node
*np)
BUG();
}
+ tegra_delay_timer.read_current_timer =
+ tegra_delay_timer_read_counter_long;
+ tegra_delay_timer.freq = 1000000;
+ register_current_timer_delay(&tegra_delay_timer);
+
ret = setup_irq(tegra_timer_irq.irq, &tegra_timer_irq);
if (ret) {
pr_err("Failed to register timer IRQ: %d\n", ret);
--
1.7.7.rc0.72.g4b5ea.dirty
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majord...@vger.kernel.org
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/
