Merge tag 'clksrc-cleanup-for-3.10-part2' of git://sources.calxeda.co…

…m/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.

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";
+	};

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

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 \

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 {

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>;

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 {

arch/arm/common/timer-sp.c

@@ -25,41 +25,37 @@
 #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;
 	}
 
 	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);

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

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);
+
+}

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

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;
 }