[PATCHv2 2/8] clocksource: sun4i: Add clocksource and sched clock drivers
Maxime Ripard
maxime.ripard at free-electrons.com
Fri Jun 28 15:56:20 EDT 2013
Use the second timer found on the Allwinner SoCs as a clock source and
sched clock, that were both not used yet on these platforms.
Signed-off-by: Maxime Ripard <maxime.ripard at free-electrons.com>
---
drivers/clocksource/sun4i_timer.c | 17 +++++++++++++++--
1 file changed, 15 insertions(+), 2 deletions(-)
diff --git a/drivers/clocksource/sun4i_timer.c b/drivers/clocksource/sun4i_timer.c
index bdf34d9..050e94f 100644
--- a/drivers/clocksource/sun4i_timer.c
+++ b/drivers/clocksource/sun4i_timer.c
@@ -19,6 +19,7 @@
#include <linux/interrupt.h>
#include <linux/irq.h>
#include <linux/irqreturn.h>
+#include <linux/sched_clock.h>
#include <linux/of.h>
#include <linux/of_address.h>
#include <linux/of_irq.h>
@@ -33,8 +34,6 @@
#define TIMER_INTVAL_REG(val) (0x10 * val + 0x14)
#define TIMER_CNTVAL_REG(val) (0x10 * val + 0x18)
-#define TIMER_SCAL 16
-
static void __iomem *timer_base;
static void sun4i_clkevt_mode(enum clock_event_mode mode,
@@ -96,6 +95,11 @@ static struct irqaction sun4i_timer_irq = {
.dev_id = &sun4i_clockevent,
};
+static u32 sun4i_timer_sched_read(void)
+{
+ return ~readl(timer_base + TIMER_CNTVAL_REG(1));
+}
+
static void __init sun4i_timer_init(struct device_node *node)
{
unsigned long rate = 0;
@@ -143,6 +147,15 @@ static void __init sun4i_timer_init(struct device_node *node)
clockevents_config_and_register(&sun4i_clockevent, rate / TIMER_SCAL,
0x1, 0xff);
+
+ writel(~0, timer_base + TIMER_INTVAL_REG(1));
+ writel(TIMER_CTL_ENABLE | TIMER_CTL_AUTORELOAD | TIMER_CTL_CLK_SRC(TIMER_CTL_CLK_SRC_OSC24M),
+ timer_base + TIMER_CTL_REG(1));
+
+ setup_sched_clock(sun4i_timer_sched_read, 32, clk_get_rate(clk));
+ clocksource_mmio_init(timer_base + TIMER_CNTVAL_REG(1), node->name,
+ clk_get_rate(clk), 300, 32,
+ clocksource_mmio_readl_down);
}
CLOCKSOURCE_OF_DECLARE(sun4i, "allwinner,sun4i-timer",
sun4i_timer_init);
--
1.8.3.1
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