[PATCH v2 04/13] ARM: timer-sp: convert to use CLKSRC_OF init

Rob Herring
2013-04-01T22:21:14Z

From: Rob Herring <rob.herring@calxeda.com>

This adds CLKSRC_OF based init for sp804 timer. The clock initialization is
refactored to support retrieving the clock(s) from the DT.

Signed-off-by: Rob Herring <rob.herring@calxeda.com>
---
arch/arm/Kconfig | 1 +
arch/arm/common/timer-sp.c | 105 +++++++++++++++++++++++++-----
arch/arm/include/asm/hardware/timer-sp.h | 16 +++--
3 files changed, 102 insertions(+), 20 deletions(-)

diff --git a/arch/arm/Kconfig b/arch/arm/Kconfig
index 5bfd584..10e3053 100644
--- a/arch/arm/Kconfig
+++ b/arch/arm/Kconfig
@@ -1173,6 +1173,7 @@ config PLAT_VERSATILE
config ARM_TIMER_SP804
bool
select CLKSRC_MMIO
+ select CLKSRC_OF if OF
select HAVE_SCHED_CLOCK

source arch/arm/mm/Kconfig
diff --git a/arch/arm/common/timer-sp.c b/arch/arm/common/timer-sp.c
index 9d2d3ba..ded926f 100644
--- a/arch/arm/common/timer-sp.c
+++ b/arch/arm/common/timer-sp.c
@@ -25,33 +25,28 @@
#include <linux/interrupt.h>
#include <linux/irq.h>
#include <linux/io.h>
+#include <linux/of.h>
+#include <linux/of_address.h>
+#include <linux/of_irq.h>

#include <asm/sched_clock.h>
#include <asm/hardware/arm_timer.h>

-static long __init sp804_get_clock_rate(const char *name)
+static long __init sp804_get_clock_rate(struct clk *clk)
{
- struct clk *clk;
long rate;
int err;

- clk = clk_get_sys("sp804", name);
- if (IS_ERR(clk)) {
- pr_err("sp804: %s clock not found: %d\n", name,
- (int)PTR_ERR(clk));
- return PTR_ERR(clk);
- }
-
err = clk_prepare(clk);
if (err) {
- pr_err("sp804: %s clock failed to prepare: %d\n", name, err);
+ pr_err("sp804: clock failed to prepare: %d\n", err);
clk_put(clk);
return err;
}

err = clk_enable(clk);
if (err) {
- pr_err("sp804: %s clock failed to enable: %d\n", name, err);
+ pr_err("sp804: clock failed to enable: %d\n", err);
clk_unprepare(clk);
clk_put(clk);
return err;
@@ -59,7 +54,7 @@ static long __init sp804_get_clock_rate(const char *name)

rate = clk_get_rate(clk);
if (rate < 0) {
- pr_err("sp804: %s clock failed to get rate: %ld\n", name, rate);
+ pr_err("sp804: clock failed to get rate: %ld\n", rate);
clk_disable(clk);
clk_unprepare(clk);
clk_put(clk);
@@ -77,9 +72,21 @@ static u32 sp804_read(void)

void __init __sp804_clocksource_and_sched_clock_init(void __iomem *base,
const char *name,
+ struct clk *clk,
int use_sched_clock)
{
- long rate = sp804_get_clock_rate(name);
+ long rate;
+
+ if (!clk) {
+ clk = clk_get_sys("sp804", name);
+ if (IS_ERR(clk)) {
+ pr_err("sp804: clock not found: %d\n",
+ (int)PTR_ERR(clk));
+ return;
+ }
+ }
+
+ rate = sp804_get_clock_rate(clk);

if (rate < 0)
return;
@@ -171,12 +178,20 @@ static struct irqaction sp804_timer_irq = {
.dev_id = &sp804_clockevent,
};

-void __init sp804_clockevents_init(void __iomem *base, unsigned int irq,
- const char *name)
+void __init __sp804_clockevents_init(void __iomem *base, unsigned int irq, struct clk *clk, const char *name)
{
struct clock_event_device *evt = &sp804_clockevent;
- long rate = sp804_get_clock_rate(name);
+ long rate;
+
+ if (!clk)
+ clk = clk_get_sys("sp804", name);
+ if (IS_ERR(clk)) {
+ pr_err("sp804: %s clock not found: %d\n", name,
+ (int)PTR_ERR(clk));
+ return;
+ }

+ rate = sp804_get_clock_rate(clk);
if (rate < 0)
return;

@@ -186,6 +201,64 @@ void __init sp804_clockevents_init(void __iomem *base, unsigned int irq,
evt->irq = irq;
evt->cpumask = cpu_possible_mask;

+ writel(0, base + TIMER_CTRL);
+
setup_irq(irq, &sp804_timer_irq);
clockevents_config_and_register(evt, rate, 0xf, 0xffffffff);
}
+
+static void __init sp804_of_init(struct device_node *np)
+{
+ static bool initialized = false;
+ void __iomem *base;
+ int irq;
+ u32 irq_num = 0;
+ struct clk *clk1, *clk2;
+ const char *name = of_get_property(np, "compatible", NULL);
+
+ base = of_iomap(np, 0);
+ if (WARN_ON(!base))
+ return;
+
+ /* Ensure timers are disabled */
+ writel(0, base + TIMER_CTRL);
+ writel(0, base + TIMER_2_BASE + TIMER_CTRL);
+
+ if (initialized || !of_device_is_available(np))
+ goto err;
+
+ clk1 = of_clk_get(np, 0);
+ if (IS_ERR(clk1))
+ clk1 = NULL;
+
+ /* Get the 2nd clock if the timer has 2 timer clocks */
+ if (of_count_phandle_with_args(np, "clocks", "#clock-cells") == 3) {
+ clk2 = of_clk_get(np, 1);
+ if (IS_ERR(clk2)) {
+ pr_err("sp804: %s clock not found: %d\n", np->name,
+ (int)PTR_ERR(clk2));
+ goto err;
+ }
+ } else
+ clk2 = clk1;
+
+ irq = irq_of_parse_and_map(np, 0);
+ if (irq <= 0)
+ goto err;
+
+ of_property_read_u32(np, "arm,sp804-has-irq", &irq_num);
+ if (irq_num == 2) {
+ __sp804_clockevents_init(base + TIMER_2_BASE, irq, clk2, name);
+ __sp804_clocksource_and_sched_clock_init(base, name, clk1, 1);
+ } else {
+ __sp804_clockevents_init(base, irq, clk1 , name);
+ __sp804_clocksource_and_sched_clock_init(base + TIMER_2_BASE,
+ name, clk2, 1);
+ }
+ initialized = true;
+
+ return;
+err:
+ iounmap(base);
+}
+CLOCKSOURCE_OF_DECLARE(sp804, "arm,sp804", sp804_of_init);
diff --git a/arch/arm/include/asm/hardware/timer-sp.h b/arch/arm/include/asm/hardware/timer-sp.h
index 2dd9d3f..bb28af7 100644
--- a/arch/arm/include/asm/hardware/timer-sp.h
+++ b/arch/arm/include/asm/hardware/timer-sp.h
@@ -1,15 +1,23 @@
+struct clk;
+
void __sp804_clocksource_and_sched_clock_init(void __iomem *,
- const char *, int);
+ const char *, struct clk *, int);
+void __sp804_clockevents_init(void __iomem *, unsigned int,
+ struct clk *, const char *);

static inline void sp804_clocksource_init(void __iomem *base, const char *name)
{
- __sp804_clocksource_and_sched_clock_init(base, name, 0);
+ __sp804_clocksource_and_sched_clock_init(base, name, NULL, 0);
}

static inline void sp804_clocksource_and_sched_clock_init(void __iomem *base,
const char *name)
{
- __sp804_clocksource_and_sched_clock_init(base, name, 1);
+ __sp804_clocksource_and_sched_clock_init(base, name, NULL, 1);
}

-void sp804_clockevents_init(void __iomem *, unsigned int, const char *);
+static inline void sp804_clockevents_init(void __iomem *base, unsigned int irq, const char *name)
+{
+ __sp804_clockevents_init(base, irq, NULL, name);
+
+}
--
1.7.10.4