Merge tag 'clksrc-cleanup-for-3.10-part2' of git://sources.calxeda.com/kernel/linux into late/clksrc

This is the 2nd part of ARM timer clean-ups for 3.10. This series has
the following changes:

- Add sched_clock selection logic to select the highest frequency clock
- Use full 64-bit arch timer counter for sched_clock
- Convert arch timer, sp804 and integrator-cp timers to CLKSRC_OF and
adapt all users to use clocksource_of_init

* tag 'clksrc-cleanup-for-3.10-part2' of git://sources.calxeda.com/kernel/linux:
  devtree: add binding documentation for sp804
  ARM: integrator-cp: convert use CLKSRC_OF for timer init
  ARM: versatile: use OF init for sp804 timer
  ARM: versatile: add versatile dtbs to dtbs target
  ARM: vexpress: remove extra timer-sp control register clearing
  ARM: dts: vexpress: disable CA9 core tile sp804 timer
  ARM: vexpress: remove sp804 OF init
  ARM: highbank: use OF init for sp804 timer
  ARM: timer-sp: convert to use CLKSRC_OF init
  OF: add empty of_device_is_available for !OF
  ARM: convert arm/arm64 arch timer to use CLKSRC_OF init
  ARM: make machine_desc->init_time default to clocksource_of_init
  ARM: arch_timer: use full 64-bit counter for sched_clock
  ARM: make sched_clock just call a function pointer
  ARM: sched_clock: allow changing to higher frequency counter

Signed-off-by: Olof Johansson <olof@lixom.net>

This has a nasty set of conflicts with the exynos MCT code, which was
moved in a separate branch, and then fixed up when merged in, but still
conflicts a bit here. It should have been sorted out by this merge though.

34 files changed, 262 insertions, 191 deletions

diff --git a/Documentation/devicetree/bindings/timer/arm,sp804.txt b/Documentation/devicetree/bindings/timer/arm,sp804.txt
new file mode 100644
index 000000000000..5cd8eee74af1
--- /dev/null
+++ b/Documentation/devicetree/bindings/timer/arm,sp804.txt
@@ -0,0 +1,29 @@
+ARM sp804 Dual Timers
+---------------------------------------
+
+Required properties:
+- compatible: Should be "arm,sp804" & "arm,primecell"
+- interrupts: Should contain the list of Dual Timer interrupts. This is the
+	interrupt for timer 1 and timer 2. In the case of a single entry, it is
+	the combined interrupt or if "arm,sp804-has-irq" is present that
+	specifies which timer interrupt is connected.
+- reg: Should contain location and length for dual timer register.
+- clocks: clocks driving the dual timer hardware. This list should be 1 or 3
+	clocks.	With 3 clocks, the order is timer0 clock, timer1 clock,
+	apb_pclk. A single clock can also be specified if the same clock is
+	used for all clock inputs.
+
+Optional properties:
+- arm,sp804-has-irq = <#>: In the case of only 1 timer irq line connected, this
+	specifies if the irq connection is for timer 1 or timer 2. A value of 1
+	or 2 should be used.
+
+Example:
+
+	timer0: timer@fc800000 {
+		compatible = "arm,sp804", "arm,primecell";
+		reg = <0xfc800000 0x1000>;
+		interrupts = <0 0 4>, <0 1 4>;
+		clocks = <&timclk1 &timclk2 &pclk>;
+		clock-names = "timer1", "timer2", "apb_pclk";
+	};
diff --git a/arch/arm/Kconfig b/arch/arm/Kconfig
index 03301cb114ac..1571a4150439 100644
--- a/arch/arm/Kconfig
+++ b/arch/arm/Kconfig
@@ -1180,6 +1180,7 @@ 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/boot/dts/Makefile b/arch/arm/boot/dts/Makefile
index 9c6255884cbb..08d298db0090 100644
--- a/arch/arm/boot/dts/Makefile
+++ b/arch/arm/boot/dts/Makefile
@@ -165,6 +165,8 @@ dtb-$(CONFIG_ARCH_TEGRA) += tegra20-harmony.dtb \
 	tegra30-cardhu-a04.dtb \
 	tegra114-dalmore.dtb \
 	tegra114-pluto.dtb
+dtb-$(CONFIG_ARCH_VERSATILE) += versatile-ab.dtb \
+	versatile-pb.dtb
 dtb-$(CONFIG_ARCH_VEXPRESS) += vexpress-v2p-ca5s.dtb \
 	vexpress-v2p-ca9.dtb \
 	vexpress-v2p-ca15-tc1.dtb \
diff --git a/arch/arm/boot/dts/integratorcp.dts b/arch/arm/boot/dts/integratorcp.dts
index 8b119399025a..ff1aea0ee043 100644
--- a/arch/arm/boot/dts/integratorcp.dts
+++ b/arch/arm/boot/dts/integratorcp.dts
@@ -24,15 +24,15 @@
 	};
 
 	timer0: timer@13000000 {
-		compatible = "arm,sp804", "arm,primecell";
+		compatible = "arm,integrator-cp-timer";
 	};
 
 	timer1: timer@13000100 {
-		compatible = "arm,sp804", "arm,primecell";
+		compatible = "arm,integrator-cp-timer";
 	};
 
 	timer2: timer@13000200 {
-		compatible = "arm,sp804", "arm,primecell";
+		compatible = "arm,integrator-cp-timer";
 	};
 
 	pic: pic@14000000 {
diff --git a/arch/arm/boot/dts/versatile-ab.dts b/arch/arm/boot/dts/versatile-ab.dts
index e2fe3195c0d1..dde75ae8b4b1 100644
--- a/arch/arm/boot/dts/versatile-ab.dts
+++ b/arch/arm/boot/dts/versatile-ab.dts
@@ -121,6 +121,18 @@
 			interrupts = <0>;
 		};
 
+		timer@101e2000 {
+			compatible = "arm,sp804", "arm,primecell";
+			reg = <0x101e2000 0x1000>;
+			interrupts = <4>;
+		};
+
+		timer@101e3000 {
+			compatible = "arm,sp804", "arm,primecell";
+			reg = <0x101e3000 0x1000>;
+			interrupts = <5>;
+		};
+
 		gpio0: gpio@101e4000 {
 			compatible = "arm,pl061", "arm,primecell";
 			reg = <0x101e4000 0x1000>;
diff --git a/arch/arm/boot/dts/vexpress-v2p-ca9.dts b/arch/arm/boot/dts/vexpress-v2p-ca9.dts
index 1420bb14d95c..62d9b225dcce 100644
--- a/arch/arm/boot/dts/vexpress-v2p-ca9.dts
+++ b/arch/arm/boot/dts/vexpress-v2p-ca9.dts
@@ -98,6 +98,7 @@
 			     <0 49 4>;
 		clocks = <&oscclk2>, <&oscclk2>;
 		clock-names = "timclk", "apb_pclk";
+		status = "disabled";
 	};
 
 	watchdog@100e5000 {
diff --git a/arch/arm/common/timer-sp.c b/arch/arm/common/timer-sp.c
index 9d2d3ba339ff..ddc740769601 100644
--- a/arch/arm/common/timer-sp.c
+++ b/arch/arm/common/timer-sp.c
@@ -25,33 +25,29 @@
 #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>
+#include <asm/hardware/timer-sp.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 +55,7 @@ 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 +73,21 @@ 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 +179,20 @@ 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 +202,98 @@ 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);
+
+static void __init integrator_cp_of_init(struct device_node *np)
+{
+	static int init_count = 0;
+	void __iomem *base;
+	int irq;
+	const char *name = of_get_property(np, "compatible", NULL);
+
+	base = of_iomap(np, 0);
+	if (WARN_ON(!base))
+		return;
+
+	/* Ensure timer is disabled */
+	writel(0, base + TIMER_CTRL);
+
+	if (init_count == 2 || !of_device_is_available(np))
+		goto err;
+
+	if (!init_count)
+		sp804_clocksource_init(base, name);
+	else {
+		irq = irq_of_parse_and_map(np, 0);
+		if (irq <= 0)
+			goto err;
+
+		sp804_clockevents_init(base, irq, name);
+	}
+
+	init_count++;
+	return;
+err:
+	iounmap(base);
+}
+CLOCKSOURCE_OF_DECLARE(intcp, "arm,integrator-cp-timer", integrator_cp_of_init);
diff --git a/arch/arm/include/asm/arch_timer.h b/arch/arm/include/asm/arch_timer.h
index 7ade91d8cc6f..7c1bfc0aea0c 100644
--- a/arch/arm/include/asm/arch_timer.h
+++ b/arch/arm/include/asm/arch_timer.h
@@ -10,8 +10,7 @@
 #include <clocksource/arm_arch_timer.h>
 
 #ifdef CONFIG_ARM_ARCH_TIMER
-int arch_timer_of_register(void);
-int arch_timer_sched_clock_init(void);
+int arch_timer_arch_init(void);
 
 /*
  * These register accessors are marked inline so the compiler can
@@ -110,16 +109,6 @@ static inline void __cpuinit arch_counter_set_user_access(void)
 
 	asm volatile("mcr p15, 0, %0, c14, c1, 0" : : "r" (cntkctl));
 }
-#else
-static inline int arch_timer_of_register(void)
-{
-	return -ENXIO;
-}
-
-static inline int arch_timer_sched_clock_init(void)
-{
-	return -ENXIO;
-}
 #endif
 
 #endif
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);
+
+}
diff --git a/arch/arm/include/asm/sched_clock.h b/arch/arm/include/asm/sched_clock.h
index e3f757263438..3d520ddca61b 100644
--- a/arch/arm/include/asm/sched_clock.h
+++ b/arch/arm/include/asm/sched_clock.h
@@ -11,4 +11,6 @@
 extern void sched_clock_postinit(void);
 extern void setup_sched_clock(u32 (*read)(void), int bits, unsigned long rate);
 
+extern unsigned long long (*sched_clock_func)(void);
+
 #endif
diff --git a/arch/arm/kernel/arch_timer.c b/arch/arm/kernel/arch_timer.c
index d957a51435d8..59dcdced6e30 100644
--- a/arch/arm/kernel/arch_timer.c
+++ b/arch/arm/kernel/arch_timer.c
@@ -22,9 +22,11 @@ static unsigned long arch_timer_read_counter_long(void)
 	return arch_timer_read_counter();
 }
 
-static u32 arch_timer_read_counter_u32(void)
+static u32 sched_clock_mult __read_mostly;
+
+static unsigned long long notrace arch_timer_sched_clock(void)
 {
-	return arch_timer_read_counter();
+	return arch_timer_read_counter() * sched_clock_mult;
 }
 
 static struct delay_timer arch_delay_timer;
@@ -37,25 +39,20 @@ static void __init arch_timer_delay_timer_register(void)
 	register_current_timer_delay(&arch_delay_timer);
 }
 
-int __init arch_timer_of_register(void)
+int __init arch_timer_arch_init(void)
 {
-	int ret;
+        u32 arch_timer_rate = arch_timer_get_rate();
 
-	ret = arch_timer_init();
-	if (ret)
-		return ret;
+	if (arch_timer_rate == 0)
+		return -ENXIO;
 
 	arch_timer_delay_timer_register();
 
-	return 0;
-}
-
-int __init arch_timer_sched_clock_init(void)
-{
-	if (arch_timer_get_rate() == 0)
-		return -ENXIO;
+	/* Cache the sched_clock multiplier to save a divide in the hot path. */
+	sched_clock_mult = NSEC_PER_SEC / arch_timer_rate;
+	sched_clock_func = arch_timer_sched_clock;
+	pr_info("sched_clock: ARM arch timer >56 bits at %ukHz, resolution %uns\n",
+		arch_timer_rate / 1000, sched_clock_mult);
 
-	setup_sched_clock(arch_timer_read_counter_u32,
-			  32, arch_timer_get_rate());
 	return 0;
 }
diff --git a/arch/arm/kernel/sched_clock.c b/arch/arm/kernel/sched_clock.c
index bd6f56b9ec21..880584852fca 100644
--- a/arch/arm/kernel/sched_clock.c
+++ b/arch/arm/kernel/sched_clock.c
@@ -20,6 +20,7 @@ struct clock_data {
 	u64 epoch_ns;
 	u32 epoch_cyc;
 	u32 epoch_cyc_copy;
+	unsigned long rate;
 	u32 mult;
 	u32 shift;
 	bool suspended;
@@ -113,11 +114,14 @@ void __init setup_sched_clock(u32 (*read)(void), int bits, unsigned long rate)
 	u64 res, wrap;
 	char r_unit;
 
+	if (cd.rate > rate)
+		return;
+
 	BUG_ON(bits > 32);
 	WARN_ON(!irqs_disabled());
-	WARN_ON(read_sched_clock != jiffy_sched_clock_read);
 	read_sched_clock = read;
 	sched_clock_mask = (1 << bits) - 1;
+	cd.rate = rate;
 
 	/* calculate the mult/shift to convert counter ticks to ns. */
 	clocks_calc_mult_shift(&cd.mult, &cd.shift, rate, NSEC_PER_SEC, 0);
@@ -161,12 +165,19 @@ void __init setup_sched_clock(u32 (*read)(void), int bits, unsigned long rate)
 	pr_debug("Registered %pF as sched_clock source\n", read);
 }
 
-unsigned long long notrace sched_clock(void)
+static unsigned long long notrace sched_clock_32(void)
 {
 	u32 cyc = read_sched_clock();
 	return cyc_to_sched_clock(cyc, sched_clock_mask);
 }
 
+unsigned long long __read_mostly (*sched_clock_func)(void) = sched_clock_32;
+
+unsigned long long notrace sched_clock(void)
+{
+	return sched_clock_func();
+}
+
 void __init sched_clock_postinit(void)
 {
 	/*
diff --git a/arch/arm/kernel/time.c b/arch/arm/kernel/time.c
index 955d92d265e5..abff4e9aaee0 100644
--- a/arch/arm/kernel/time.c
+++ b/arch/arm/kernel/time.c
@@ -22,6 +22,7 @@
 #include <linux/errno.h>
 #include <linux/profile.h>
 #include <linux/timer.h>
+#include <linux/clocksource.h>
 #include <linux/irq.h>
 
 #include <asm/thread_info.h>
@@ -115,6 +116,10 @@ int __init register_persistent_clock(clock_access_fn read_boot,
 
 void __init time_init(void)
 {
-	machine_desc->init_time();
+	if (machine_desc->init_time)
+		machine_desc->init_time();
+	else
+		clocksource_of_init();
+
 	sched_clock_postinit();
 }
diff --git a/arch/arm/mach-exynos/mach-exynos5-dt.c b/arch/arm/mach-exynos/mach-exynos5-dt.c
index 7da4791bfb8b..be7eaac0df01 100644
--- a/arch/arm/mach-exynos/mach-exynos5-dt.c
+++ b/arch/arm/mach-exynos/mach-exynos5-dt.c
@@ -217,7 +217,6 @@ DT_MACHINE_START(EXYNOS5_DT, "SAMSUNG EXYNOS5 (Flattened Device Tree)")
 	.map_io		= exynos5_dt_map_io,
 	.init_machine	= exynos5_dt_machine_init,
 	.init_late	= exynos_init_late,
-	.init_time	= clocksource_of_init,
 	.dt_compat	= exynos5_dt_compat,
 	.restart        = exynos5_restart,
 	.reserve	= exynos5_reserve,
diff --git a/arch/arm/mach-highbank/highbank.c b/arch/arm/mach-highbank/highbank.c
index 76c1170b3528..e7df2dd43a40 100644
--- a/arch/arm/mach-highbank/highbank.c
+++ b/arch/arm/mach-highbank/highbank.c
@@ -15,6 +15,7 @@
  */
 #include <linux/clk.h>
 #include <linux/clkdev.h>
+#include <linux/clocksource.h>
 #include <linux/dma-mapping.h>
 #include <linux/io.h>
 #include <linux/irq.h>
@@ -28,12 +29,9 @@
 #include <linux/amba/bus.h>
 #include <linux/clk-provider.h>
 
-#include <asm/arch_timer.h>
 #include <asm/cacheflush.h>
 #include <asm/cputype.h>
 #include <asm/smp_plat.h>
-#include <asm/hardware/arm_timer.h>
-#include <asm/hardware/timer-sp.h>
 #include <asm/hardware/cache-l2x0.h>
 #include <asm/mach/arch.h>
 #include <asm/mach/map.h>
@@ -90,36 +88,16 @@ static void __init highbank_init_irq(void)
 #endif
 }
 
-static struct clk_lookup lookup = {
-	.dev_id = "sp804",
-	.con_id = NULL,
-};
-
 static void __init highbank_timer_init(void)
 {
-	int irq;
 	struct device_node *np;
-	void __iomem *timer_base;
 
 	/* Map system registers */
 	np = of_find_compatible_node(NULL, NULL, "calxeda,hb-sregs");
 	sregs_base = of_iomap(np, 0);
 	WARN_ON(!sregs_base);
 
-	np = of_find_compatible_node(NULL, NULL, "arm,sp804");
-	timer_base = of_iomap(np, 0);
-	WARN_ON(!timer_base);
-	irq = irq_of_parse_and_map(np, 0);
-
 	of_clk_init(NULL);
-	lookup.clk = of_clk_get(np, 0);
-	clkdev_add(&lookup);
-
-	sp804_clocksource_and_sched_clock_init(timer_base + 0x20, "timer1");
-	sp804_clockevents_init(timer_base, irq, "timer0");
-
-	arch_timer_of_register();
-	arch_timer_sched_clock_init();
 
 	clocksource_of_init();
 }
diff --git a/arch/arm/mach-integrator/integrator_cp.c b/arch/arm/mach-integrator/integrator_cp.c
index da1091be0887..8c60fcb08a98 100644
--- a/arch/arm/mach-integrator/integrator_cp.c
+++ b/arch/arm/mach-integrator/integrator_cp.c
@@ -250,39 +250,6 @@ static void __init intcp_init_early(void)
 }
 
 #ifdef CONFIG_OF
-
-static void __init cp_of_timer_init(void)
-{
-	struct device_node *node;
-	const char *path;
-	void __iomem *base;
-	int err;
-	int irq;
-
-	err = of_property_read_string(of_aliases,
-				"arm,timer-primary", &path);
-	if (WARN_ON(err))
-		return;
-	node = of_find_node_by_path(path);
-	base = of_iomap(node, 0);
-	if (WARN_ON(!base))
-		return;
-	writel(0, base + TIMER_CTRL);
-	sp804_clocksource_init(base, node->name);
-
-	err = of_property_read_string(of_aliases,
-				"arm,timer-secondary", &path);
-	if (WARN_ON(err))
-		return;
-	node = of_find_node_by_path(path);
-	base = of_iomap(node, 0);
-	if (WARN_ON(!base))
-		return;
-	irq = irq_of_parse_and_map(node, 0);
-	writel(0, base + TIMER_CTRL);
-	sp804_clockevents_init(base, irq, node->name);
-}
-
 static const struct of_device_id fpga_irq_of_match[] __initconst = {
 	{ .compatible = "arm,versatile-fpga-irq", .data = fpga_irq_of_init, },
 	{ /* Sentinel */ }
@@ -383,7 +350,6 @@ DT_MACHINE_START(INTEGRATOR_CP_DT, "ARM Integrator/CP (Device Tree)")
 	.init_early	= intcp_init_early,
 	.init_irq	= intcp_init_irq_of,
 	.handle_irq	= fpga_handle_irq,
-	.init_time	= cp_of_timer_init,
 	.init_machine	= intcp_init_of,
 	.restart	= integrator_restart,
 	.dt_compat      = intcp_dt_board_compat,
diff --git a/arch/arm/mach-omap2/timer.c b/arch/arm/mach-omap2/timer.c
index f12aa6c15da4..d5a13dcb64b8 100644
--- a/arch/arm/mach-omap2/timer.c
+++ b/arch/arm/mach-omap2/timer.c
@@ -46,7 +46,6 @@
 #include <asm/smp_twd.h>
 #include <asm/sched_clock.h>
 
-#include <asm/arch_timer.h>
 #include "omap_hwmod.h"
 #include "omap_device.h"
 #include <plat/counter-32k.h>
@@ -627,9 +626,7 @@ void __init omap5_realtime_timer_init(void)
 	omap4_sync32k_timer_init();
 	realtime_counter_init();
 
-	err = arch_timer_of_register();
-	if (err)
-		pr_err("%s: arch_timer_register failed %d\n", __func__, err);
+        clocksource_of_init();
 }
 #endif /* CONFIG_SOC_OMAP5 */
 
diff --git a/arch/arm/mach-shmobile/board-kzm9d.c b/arch/arm/mach-shmobile/board-kzm9d.c
index c254782aa727..c016ccd92433 100644
--- a/arch/arm/mach-shmobile/board-kzm9d.c
+++ b/arch/arm/mach-shmobile/board-kzm9d.c
@@ -90,6 +90,5 @@ DT_MACHINE_START(KZM9D_DT, "kzm9d")
 	.init_irq	= emev2_init_irq,
 	.init_machine	= kzm9d_add_standard_devices,
 	.init_late	= shmobile_init_late,
-	.init_time	= shmobile_timer_init,
 	.dt_compat	= kzm9d_boards_compat_dt,
 MACHINE_END
diff --git a/arch/arm/mach-shmobile/setup-emev2.c b/arch/arm/mach-shmobile/setup-emev2.c
index e4545c152722..899a86c31ec9 100644
--- a/arch/arm/mach-shmobile/setup-emev2.c
+++ b/arch/arm/mach-shmobile/setup-emev2.c
@@ -456,7 +456,6 @@ DT_MACHINE_START(EMEV2_DT, "Generic Emma Mobile EV2 (Flattened Device Tree)")
 	.nr_irqs	= NR_IRQS_LEGACY,
 	.init_irq	= irqchip_init,
 	.init_machine	= emev2_add_standard_devices_dt,
-	.init_time	= shmobile_timer_init,
 	.dt_compat	= emev2_boards_compat_dt,
 MACHINE_END
 
diff --git a/arch/arm/mach-shmobile/setup-r8a7740.c b/arch/arm/mach-shmobile/setup-r8a7740.c
index 8b85d4d8fab6..104b474a2ccf 100644
--- a/arch/arm/mach-shmobile/setup-r8a7740.c
+++ b/arch/arm/mach-shmobile/setup-r8a7740.c
@@ -906,7 +906,6 @@ DT_MACHINE_START(R8A7740_DT, "Generic R8A7740 (Flattened Device Tree)")
 	.init_irq	= r8a7740_init_irq,
 	.handle_irq	= shmobile_handle_irq_intc,
 	.init_machine	= r8a7740_add_standard_devices_dt,
-	.init_time	= shmobile_timer_init,
 	.dt_compat	= r8a7740_boards_compat_dt,
 MACHINE_END
 
diff --git a/arch/arm/mach-shmobile/setup-sh7372.c b/arch/arm/mach-shmobile/setup-sh7372.c
index 59c7146bf66f..5502d624aca6 100644
--- a/arch/arm/mach-shmobile/setup-sh7372.c
+++ b/arch/arm/mach-shmobile/setup-sh7372.c
@@ -1175,7 +1175,6 @@ DT_MACHINE_START(SH7372_DT, "Generic SH7372 (Flattened Device Tree)")
 	.init_irq	= sh7372_init_irq,
 	.handle_irq	= shmobile_handle_irq_intc,
 	.init_machine	= sh7372_add_standard_devices_dt,
-	.init_time	= shmobile_timer_init,
 	.dt_compat	= sh7372_boards_compat_dt,
 MACHINE_END
 
diff --git a/arch/arm/mach-shmobile/setup-sh73a0.c b/arch/arm/mach-shmobile/setup-sh73a0.c
index e8cd93a5c550..fdf3894b1cc3 100644
--- a/arch/arm/mach-shmobile/setup-sh73a0.c
+++ b/arch/arm/mach-shmobile/setup-sh73a0.c
@@ -1037,7 +1037,6 @@ DT_MACHINE_START(SH73A0_DT, "Generic SH73A0 (Flattened Device Tree)")
 	.nr_irqs	= NR_IRQS_LEGACY,
 	.init_irq	= irqchip_init,
 	.init_machine	= sh73a0_add_standard_devices_dt,
-	.init_time	= shmobile_timer_init,
 	.dt_compat	= sh73a0_boards_compat_dt,
 MACHINE_END
 #endif /* CONFIG_USE_OF */
diff --git a/arch/arm/mach-shmobile/timer.c b/arch/arm/mach-shmobile/timer.c
index 3d16d4dff01b..f321dbeb2379 100644
--- a/arch/arm/mach-shmobile/timer.c
+++ b/arch/arm/mach-shmobile/timer.c
@@ -19,10 +19,8 @@
  *
  */
 #include <linux/platform_device.h>
+#include <linux/clocksource.h>
 #include <linux/delay.h>
-#include <asm/arch_timer.h>
-#include <asm/mach/time.h>
-#include <asm/smp_twd.h>
 
 void __init shmobile_setup_delay(unsigned int max_cpu_core_mhz,
 				 unsigned int mult, unsigned int div)
@@ -63,6 +61,5 @@ void __init shmobile_earlytimer_init(void)
 
 void __init shmobile_timer_init(void)
 {
-	arch_timer_of_register();
-	arch_timer_sched_clock_init();
+	clocksource_of_init();
 }
diff --git a/arch/arm/mach-versatile/core.c b/arch/arm/mach-versatile/core.c
index 25160aeaa3b7..54bb80b012ac 100644
--- a/arch/arm/mach-versatile/core.c
+++ b/arch/arm/mach-versatile/core.c
@@ -749,12 +749,25 @@ void versatile_restart(char mode, const char *cmd)
 /* Early initializations */
 void __init versatile_init_early(void)
 {
+	u32 val;
 	void __iomem *sys = __io_address(VERSATILE_SYS_BASE);
 
 	osc4_clk.vcoreg	= sys + VERSATILE_SYS_OSCCLCD_OFFSET;
 	clkdev_add_table(lookups, ARRAY_SIZE(lookups));
 
 	versatile_sched_clock_init(sys + VERSATILE_SYS_24MHz_OFFSET, 24000000);
+
+	/*
+	 * set clock frequency:
+	 *	VERSATILE_REFCLK is 32KHz
+	 *	VERSATILE_TIMCLK is 1MHz
+	 */
+	val = readl(__io_address(VERSATILE_SCTL_BASE));
+	writel((VERSATILE_TIMCLK << VERSATILE_TIMER1_EnSel) |
+	       (VERSATILE_TIMCLK << VERSATILE_TIMER2_EnSel) |
+	       (VERSATILE_TIMCLK << VERSATILE_TIMER3_EnSel) |
+	       (VERSATILE_TIMCLK << VERSATILE_TIMER4_EnSel) | val,
+	       __io_address(VERSATILE_SCTL_BASE));
 }
 
 void __init versatile_init(void)
@@ -785,19 +798,6 @@ void __init versatile_init(void)
  */
 void __init versatile_timer_init(void)
 {
-	u32 val;
-
-	/* 
-	 * set clock frequency: 
-	 *	VERSATILE_REFCLK is 32KHz
-	 *	VERSATILE_TIMCLK is 1MHz
-	 */
-	val = readl(__io_address(VERSATILE_SCTL_BASE));
-	writel((VERSATILE_TIMCLK << VERSATILE_TIMER1_EnSel) |
-	       (VERSATILE_TIMCLK << VERSATILE_TIMER2_EnSel) | 
-	       (VERSATILE_TIMCLK << VERSATILE_TIMER3_EnSel) |
-	       (VERSATILE_TIMCLK << VERSATILE_TIMER4_EnSel) | val,
-	       __io_address(VERSATILE_SCTL_BASE));
 
 	/*
 	 * Initialise to a known state (all timers off)
diff --git a/arch/arm/mach-versatile/versatile_dt.c b/arch/arm/mach-versatile/versatile_dt.c
index 2558f2e957c3..3621b000a0f6 100644
--- a/arch/arm/mach-versatile/versatile_dt.c
+++ b/arch/arm/mach-versatile/versatile_dt.c
@@ -45,7 +45,6 @@ DT_MACHINE_START(VERSATILE_PB, "ARM-Versatile (Device Tree Support)")
 	.map_io		= versatile_map_io,
 	.init_early	= versatile_init_early,
 	.init_irq	= versatile_init_irq,
-	.init_time	= versatile_timer_init,
 	.init_machine	= versatile_dt_init,
 	.dt_compat	= versatile_dt_match,
 	.restart	= versatile_restart,
diff --git a/arch/arm/mach-vexpress/v2m.c b/arch/arm/mach-vexpress/v2m.c
index d0ad78998cb6..09e571ddc984 100644
--- a/arch/arm/mach-vexpress/v2m.c
+++ b/arch/arm/mach-vexpress/v2m.c
@@ -1,6 +1,7 @@
 /*
  * Versatile Express V2M Motherboard Support
  */
+#include <linux/clocksource.h>
 #include <linux/device.h>
 #include <linux/amba/bus.h>
 #include <linux/amba/mmci.h>
@@ -23,7 +24,6 @@
 #include <linux/regulator/machine.h>
 #include <linux/vexpress.h>
 
-#include <asm/arch_timer.h>
 #include <asm/mach-types.h>
 #include <asm/sizes.h>
 #include <asm/mach/arch.h>
@@ -61,9 +61,6 @@ static void __init v2m_sp804_init(void __iomem *base, unsigned int irq)
 	if (WARN_ON(!base || irq == NO_IRQ))
 		return;
 
-	writel(0, base + TIMER_1_BASE + TIMER_CTRL);
-	writel(0, base + TIMER_2_BASE + TIMER_CTRL);
-
 	sp804_clocksource_init(base + TIMER_2_BASE, "v2m-timer1");
 	sp804_clockevents_init(base + TIMER_1_BASE, irq, "v2m-timer0");
 }
@@ -431,25 +428,11 @@ void __init v2m_dt_init_early(void)
 
 static void __init v2m_dt_timer_init(void)
 {
-	struct device_node *node = NULL;
-
 	vexpress_clk_of_init();
 
 	clocksource_of_init();
-	do {
-		node = of_find_compatible_node(node, NULL, "arm,sp804");
-	} while (node && vexpress_get_site_by_node(node) != VEXPRESS_SITE_MB);
-	if (node) {
-		pr_info("Using SP804 '%s' as a clock & events source\n",
-				node->full_name);
-		v2m_sp804_init(of_iomap(node, 0),
-				irq_of_parse_and_map(node, 0));
-	}
-
-	arch_timer_of_register();
 
-	if (arch_timer_sched_clock_init() != 0)
-		versatile_sched_clock_init(vexpress_get_24mhz_clock_base(),
+	versatile_sched_clock_init(vexpress_get_24mhz_clock_base(),
 				24000000);
 }
 
diff --git a/arch/arm/mach-virt/virt.c b/arch/arm/mach-virt/virt.c
index 31666f6b4373..adc0945255ae 100644
--- a/arch/arm/mach-virt/virt.c
+++ b/arch/arm/mach-virt/virt.c
@@ -23,21 +23,13 @@
 #include <linux/of_platform.h>
 #include <linux/smp.h>
 
-#include <asm/arch_timer.h>
 #include <asm/mach/arch.h>
-#include <asm/mach/time.h>
 
 static void __init virt_init(void)
 {
 	of_platform_populate(NULL, of_default_bus_match_table, NULL, NULL);
 }
 
-static void __init virt_timer_init(void)
-{
-	WARN_ON(arch_timer_of_register() != 0);
-	WARN_ON(arch_timer_sched_clock_init() != 0);
-}
-
 static const char *virt_dt_match[] = {
 	"linux,dummy-virt",
 	NULL
@@ -47,7 +39,6 @@ extern struct smp_operations virt_smp_ops;
 
 DT_MACHINE_START(VIRT, "Dummy Virtual Machine")
 	.init_irq	= irqchip_init,
-	.init_time	= virt_timer_init,
 	.init_machine	= virt_init,
 	.smp		= smp_ops(virt_smp_ops),
 	.dt_compat	= virt_dt_match,
diff --git a/arch/arm64/include/asm/arch_timer.h b/arch/arm64/include/asm/arch_timer.h
index 91e2a6a6fcd4..bf6ab242f047 100644
--- a/arch/arm64/include/asm/arch_timer.h
+++ b/arch/arm64/include/asm/arch_timer.h
@@ -130,4 +130,9 @@ static inline u64 arch_counter_get_cntvct(void)
 	return cval;
 }
 
+static inline int arch_timer_arch_init(void)
+{
+	return 0;
+}
+
 #endif
diff --git a/arch/arm64/kernel/time.c b/arch/arm64/kernel/time.c
index b0ef18d14c3b..a551f88ae2c1 100644
--- a/arch/arm64/kernel/time.c
+++ b/arch/arm64/kernel/time.c
@@ -32,6 +32,7 @@
 #include <linux/timer.h>
 #include <linux/irq.h>
 #include <linux/delay.h>
+#include <linux/clocksource.h>
 
 #include <clocksource/arm_arch_timer.h>
 
@@ -77,10 +78,11 @@ void __init time_init(void)
 {
 	u32 arch_timer_rate;
 
-	if (arch_timer_init())
-		panic("Unable to initialise architected timer.\n");
+	clocksource_of_init();
 
 	arch_timer_rate = arch_timer_get_rate();
+	if (!arch_timer_rate)
+		panic("Unable to initialise architected timer.\n");
 
 	/* Cache the sched_clock multiplier to save a divide in the hot path. */
 	sched_clock_mult = NSEC_PER_SEC / arch_timer_rate;
diff --git a/drivers/clocksource/Kconfig b/drivers/clocksource/Kconfig
index 73fcddb8314d..29ba35e6a143 100644
--- a/drivers/clocksource/Kconfig
+++ b/drivers/clocksource/Kconfig
@@ -65,6 +65,7 @@ config CLKSRC_DBX500_PRCMU_SCHED_CLOCK
 
 config ARM_ARCH_TIMER
 	bool
+	select CLKSRC_OF if OF
 
 config CLKSRC_METAG_GENERIC
 	def_bool y if METAG
diff --git a/drivers/clocksource/arm_arch_timer.c b/drivers/clocksource/arm_arch_timer.c
index d7ad425ab9b3..122ff05628b5 100644
--- a/drivers/clocksource/arm_arch_timer.c
+++ b/drivers/clocksource/arm_arch_timer.c
@@ -337,22 +337,14 @@ out:
 	return err;
 }
 
-static const struct of_device_id arch_timer_of_match[] __initconst = {
-	{ .compatible	= "arm,armv7-timer",	},
-	{ .compatible	= "arm,armv8-timer",	},
-	{},
-};
-
-int __init arch_timer_init(void)
+static void __init arch_timer_init(struct device_node *np)
 {
-	struct device_node *np;
 	u32 freq;
 	int i;
 
-	np = of_find_matching_node(NULL, arch_timer_of_match);
-	if (!np) {
-		pr_err("arch_timer: can't find DT node\n");
-		return -ENODEV;
+	if (arch_timer_get_rate()) {
+		pr_warn("arch_timer: multiple nodes in dt, skipping\n");
+		return;
 	}
 
 	/* Try to determine the frequency from the device tree or CNTFRQ */
@@ -378,7 +370,7 @@ int __init arch_timer_init(void)
 		if (!arch_timer_ppi[PHYS_SECURE_PPI] ||
 		    !arch_timer_ppi[PHYS_NONSECURE_PPI]) {
 			pr_warn("arch_timer: No interrupt available, giving up\n");
-			return -EINVAL;
+			return;
 		}
 	}
 
@@ -387,5 +379,8 @@ int __init arch_timer_init(void)
 	else
 		arch_timer_read_counter = arch_counter_get_cntpct;
 
-	return arch_timer_register();
+	arch_timer_register();
+	arch_timer_arch_init();
 }
+CLOCKSOURCE_OF_DECLARE(armv7_arch_timer, "arm,armv7-timer", arch_timer_init);
+CLOCKSOURCE_OF_DECLARE(armv8_arch_timer, "arm,armv8-timer", arch_timer_init);
diff --git a/drivers/clocksource/exynos_mct.c b/drivers/clocksource/exynos_mct.c
index 957af8636c9d..b078d7cbc930 100644
--- a/drivers/clocksource/exynos_mct.c
+++ b/drivers/clocksource/exynos_mct.c
@@ -24,7 +24,6 @@
 #include <linux/of_address.h>
 #include <linux/clocksource.h>
 
-#include <asm/arch_timer.h>
 #include <asm/localtimer.h>
 
 #include <plat/cpu.h>
diff --git a/include/clocksource/arm_arch_timer.h b/include/clocksource/arm_arch_timer.h
index 2603267b1a29..e6c9c4cc9b23 100644
--- a/include/clocksource/arm_arch_timer.h
+++ b/include/clocksource/arm_arch_timer.h
@@ -31,18 +31,12 @@
 
 #ifdef CONFIG_ARM_ARCH_TIMER
 
-extern int arch_timer_init(void);
 extern u32 arch_timer_get_rate(void);
 extern u64 (*arch_timer_read_counter)(void);
 extern struct timecounter *arch_timer_get_timecounter(void);
 
 #else
 
-static inline int arch_timer_init(void)
-{
-	return -ENXIO;
-}
-
 static inline u32 arch_timer_get_rate(void)
 {
 	return 0;
diff --git a/include/linux/of.h b/include/linux/of.h
index c0747a44eaff..b0f3bbd0216b 100644
--- a/include/linux/of.h
+++ b/include/linux/of.h
@@ -382,6 +382,11 @@ static inline int of_device_is_compatible(const struct device_node *device,
 	return 0;
 }
 
+static inline int of_device_is_available(const struct device_node *device)
+{
+	return 0;
+}
+
 static inline struct property *of_find_property(const struct device_node *np,
 						const char *name,
 						int *lenp)