ARM: timer-sp: convert to use CLKSRC_OF init

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>

3 files changed, 102 insertions, 20 deletions

diff --git a/arch/arm/Kconfig b/arch/arm/Kconfig
index 5bfd584929c8..10e3053b7d8a 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 9d2d3ba339ff..ded926f7c4e8 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 2dd9d3f83f29..bb28af7c32de 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);
+
+}