+++ /dev/null
-From 403eb25e5ae7a2169d8c1eae9df4162815e7c3ba Mon Sep 17 00:00:00 2001
-From: Stuart Menefy <stuart.menefy at>
-Date: Wed, 26 Jun 2013 11:48:38 +0000
-Subject: [PATCH 01/17] clocksource:arm_global_timer: Add ARM global timer
- support.
-
-This is a simple driver for the global timer module found in the Cortex
-A9-MP cores from revision r1p0 onwards. This should be able to perform
-the functions of the system timer and the local timer in an SMP system.
-
-The global timer has the following features:
- The global timer is a 64-bit incrementing counter with an
-auto-incrementing feature. It continues incrementing after sending
-interrupts. The global timer is memory mapped in the private memory
-region.
- The global timer is accessible to all Cortex-A9 processors in the
-cluster. Each Cortex-A9 processor has a private 64-bit comparator that
-is used to assert a private interrupt when the global timer has reached
-the comparator value. All the Cortex-A9 processors in a design use the
-banked ID, ID27, for this interrupt. ID27 is sent to the Interrupt
-Controller as a Private Peripheral Interrupt. The global timer is
-clocked by PERIPHCLK.
-
-Signed-off-by: Stuart Menefy <stuart.menefy@st.com>
-Signed-off-by: Srinivas Kandagatla <srinivas.kandagatla@st.com>
-CC: Arnd Bergmann <arnd@arndb.de>
-CC: Rob Herring <robherring2@gmail.com>
-CC: Linus Walleij <linus.walleij@linaro.org>
-CC: Will Deacon <will.deacon@arm.com>
-CC: Thomas Gleixner <tglx@linutronix.de>
----
- .../devicetree/bindings/arm/global_timer.txt | 21 ++
- drivers/clocksource/Kconfig | 13 +
- drivers/clocksource/Makefile | 1 +
- drivers/clocksource/arm_global_timer.c | 325 ++++++++++++++++++++
- 4 files changed, 360 insertions(+)
- create mode 100644 Documentation/devicetree/bindings/arm/global_timer.txt
- create mode 100644 drivers/clocksource/arm_global_timer.c
-
---- /dev/null
-+++ b/Documentation/devicetree/bindings/arm/global_timer.txt
-@@ -0,0 +1,21 @@
-+
-+* ARM Global Timer
-+ Cortex-A9 are often associated with a per-core Global timer.
-+
-+** Timer node required properties:
-+
-+- compatible : Should be "arm,cortex-a9-global-timer"
-+ Driver supports versions r2p0 and above.
-+
-+- interrupts : One interrupt to each core
-+
-+- reg : Specify the base address and the size of the GT timer
-+ register window.
-+
-+Example:
-+
-+ timer@2c000600 {
-+ compatible = "arm,cortex-a9-global-timer";
-+ reg = <0x2c000600 0x20>;
-+ interrupts = <1 13 0xf01>;
-+ };
---- a/drivers/clocksource/Kconfig
-+++ b/drivers/clocksource/Kconfig
-@@ -67,6 +67,19 @@ config ARM_ARCH_TIMER
- bool
- select CLKSRC_OF if OF
-
-+config ARM_GLOBAL_TIMER
-+ bool
-+ select CLKSRC_OF if OF
-+ help
-+ This options enables support for the ARM global timer unit
-+
-+config CLKSRC_ARM_GLOBAL_TIMER_SCHED_CLOCK
-+ bool
-+ depends on ARM_GLOBAL_TIMER
-+ default y
-+ help
-+ Use ARM global timer clock source as sched_clock
-+
- config CLKSRC_METAG_GENERIC
- def_bool y if METAG
- help
---- a/drivers/clocksource/Makefile
-+++ b/drivers/clocksource/Makefile
-@@ -28,4 +28,5 @@ obj-$(CONFIG_CLKSRC_EXYNOS_MCT) += exyno
- obj-$(CONFIG_CLKSRC_SAMSUNG_PWM) += samsung_pwm_timer.o
-
- obj-$(CONFIG_ARM_ARCH_TIMER) += arm_arch_timer.o
-+obj-$(CONFIG_ARM_GLOBAL_TIMER) += arm_global_timer.o
- obj-$(CONFIG_CLKSRC_METAG_GENERIC) += metag_generic.o
---- /dev/null
-+++ b/drivers/clocksource/arm_global_timer.c
-@@ -0,0 +1,325 @@
-+/*
-+ * drivers/clocksource/arm_global_timer.c
-+ *
-+ * Copyright (C) 2013 STMicroelectronics (R&D) Limited.
-+ * Author: Stuart Menefy <stuart.menefy@st.com>
-+ * Author: Srinivas Kandagatla <srinivas.kandagatla@st.com>
-+ *
-+ * This program is free software; you can redistribute it and/or modify
-+ * it under the terms of the GNU General Public License version 2 as
-+ * published by the Free Software Foundation.
-+ */
-+
-+#include <linux/init.h>
-+#include <linux/interrupt.h>
-+#include <linux/clocksource.h>
-+#include <linux/clockchips.h>
-+#include <linux/cpu.h>
-+#include <linux/clk.h>
-+#include <linux/err.h>
-+#include <linux/io.h>
-+#include <linux/of.h>
-+#include <linux/of_irq.h>
-+#include <linux/of_address.h>
-+
-+#include <asm/sched_clock.h>
-+#include <asm/cputype.h>
-+
-+#define GT_COUNTER0 0x00
-+#define GT_COUNTER1 0x04
-+
-+#define GT_CONTROL 0x08
-+#define GT_CONTROL_TIMER_ENABLE BIT(0) /* this bit is NOT banked */
-+#define GT_CONTROL_COMP_ENABLE BIT(1) /* banked */
-+#define GT_CONTROL_IRQ_ENABLE BIT(2) /* banked */
-+#define GT_CONTROL_AUTO_INC BIT(3) /* banked */
-+
-+#define GT_INT_STATUS 0x0c
-+#define GT_INT_STATUS_EVENT_FLAG BIT(0)
-+
-+#define GT_COMP0 0x10
-+#define GT_COMP1 0x14
-+#define GT_AUTO_INC 0x18
-+
-+/*
-+ * We are expecting to be clocked by the ARM peripheral clock.
-+ *
-+ * Note: it is assumed we are using a prescaler value of zero, so this is
-+ * the units for all operations.
-+ */
-+static void __iomem *gt_base;
-+static unsigned long gt_clk_rate;
-+static int gt_ppi;
-+static struct clock_event_device __percpu *gt_evt;
-+
-+/*
-+ * To get the value from the Global Timer Counter register proceed as follows:
-+ * 1. Read the upper 32-bit timer counter register
-+ * 2. Read the lower 32-bit timer counter register
-+ * 3. Read the upper 32-bit timer counter register again. If the value is
-+ * different to the 32-bit upper value read previously, go back to step 2.
-+ * Otherwise the 64-bit timer counter value is correct.
-+ */
-+static u64 gt_counter_read(void)
-+{
-+ u64 counter;
-+ u32 lower;
-+ u32 upper, old_upper;
-+
-+ upper = readl_relaxed(gt_base + GT_COUNTER1);
-+ do {
-+ old_upper = upper;
-+ lower = readl_relaxed(gt_base + GT_COUNTER0);
-+ upper = readl_relaxed(gt_base + GT_COUNTER1);
-+ } while (upper != old_upper);
-+
-+ counter = upper;
-+ counter <<= 32;
-+ counter |= lower;
-+ return counter;
-+}
-+
-+/**
-+ * To ensure that updates to comparator value register do not set the
-+ * Interrupt Status Register proceed as follows:
-+ * 1. Clear the Comp Enable bit in the Timer Control Register.
-+ * 2. Write the lower 32-bit Comparator Value Register.
-+ * 3. Write the upper 32-bit Comparator Value Register.
-+ * 4. Set the Comp Enable bit and, if necessary, the IRQ enable bit.
-+ */
-+static void gt_compare_set(unsigned long delta, int periodic)
-+{
-+ u64 counter = gt_counter_read();
-+ unsigned long ctrl = readl(gt_base + GT_CONTROL);
-+
-+ counter += delta;
-+ ctrl &= ~(GT_CONTROL_COMP_ENABLE | GT_CONTROL_IRQ_ENABLE);
-+
-+ writel(ctrl, gt_base + GT_CONTROL);
-+ writel(lower_32_bits(counter), gt_base + GT_COMP0);
-+ writel(upper_32_bits(counter), gt_base + GT_COMP1);
-+
-+ if (periodic) {
-+ writel(delta, gt_base + GT_AUTO_INC);
-+ ctrl |= GT_CONTROL_AUTO_INC;
-+ }
-+
-+ ctrl |= GT_CONTROL_COMP_ENABLE | GT_CONTROL_IRQ_ENABLE;
-+ writel(ctrl, gt_base + GT_CONTROL);
-+}
-+
-+static void gt_clockevent_set_mode(enum clock_event_mode mode,
-+ struct clock_event_device *clk)
-+{
-+ unsigned long ctrl;
-+
-+ switch (mode) {
-+ case CLOCK_EVT_MODE_PERIODIC:
-+ gt_compare_set(DIV_ROUND_CLOSEST(gt_clk_rate, HZ), 1);
-+ break;
-+ case CLOCK_EVT_MODE_ONESHOT:
-+ case CLOCK_EVT_MODE_UNUSED:
-+ case CLOCK_EVT_MODE_SHUTDOWN:
-+ ctrl = readl(gt_base + GT_CONTROL);
-+ ctrl &= ~(GT_CONTROL_COMP_ENABLE |
-+ GT_CONTROL_IRQ_ENABLE | GT_CONTROL_AUTO_INC);
-+ writel(ctrl, gt_base + GT_CONTROL);
-+ break;
-+ default:
-+ break;
-+ }
-+}
-+
-+static int gt_clockevent_set_next_event(unsigned long evt,
-+ struct clock_event_device *unused)
-+{
-+ gt_compare_set(evt, 0);
-+ return 0;
-+}
-+
-+static irqreturn_t gt_clockevent_interrupt(int irq, void *dev_id)
-+{
-+ struct clock_event_device *evt = dev_id;
-+
-+ if (readl_relaxed(gt_base + GT_INT_STATUS) &
-+ GT_INT_STATUS_EVENT_FLAG) {
-+ /**
-+ * ERRATA 740657( Global Timer can send 2 interrupts for
-+ * the same event in single-shot mode)
-+ * Workaround:
-+ * Either disable single-shot mode.
-+ * Or
-+ * Modify the Interrupt Handler to avoid the
-+ * offending sequence. This is achieved by clearing
-+ * the Global Timer flag _after_ having incremented
-+ * the Comparator register value to a higher value.
-+ */
-+ if (!(readl_relaxed(gt_base + GT_CONTROL) &
-+ GT_CONTROL_AUTO_INC))
-+ gt_compare_set(ULONG_MAX, 0);
-+
-+ writel_relaxed(GT_INT_STATUS_EVENT_FLAG,
-+ gt_base + GT_INT_STATUS);
-+
-+ evt->event_handler(evt);
-+ return IRQ_HANDLED;
-+ }
-+
-+ return IRQ_NONE;
-+}
-+
-+static int __cpuinit gt_clockevents_init(struct clock_event_device *clk)
-+{
-+ int cpu = smp_processor_id();
-+
-+ clk->name = "arm_global_timer";
-+ clk->features = CLOCK_EVT_FEAT_PERIODIC | CLOCK_EVT_FEAT_ONESHOT;
-+ clk->set_mode = gt_clockevent_set_mode;
-+ clk->set_next_event = gt_clockevent_set_next_event;
-+ clk->cpumask = cpumask_of(cpu);
-+ clk->rating = 300;
-+ clk->irq = gt_ppi;
-+ clockevents_config_and_register(clk, gt_clk_rate,
-+ 1, 0xffffffff);
-+ enable_percpu_irq(clk->irq, IRQ_TYPE_NONE);
-+ return 0;
-+}
-+
-+static void gt_clockevents_stop(struct clock_event_device *clk)
-+{
-+ gt_clockevent_set_mode(CLOCK_EVT_MODE_UNUSED, clk);
-+ disable_percpu_irq(clk->irq);
-+}
-+
-+static cycle_t gt_clocksource_read(struct clocksource *cs)
-+{
-+ return gt_counter_read();
-+}
-+
-+static struct clocksource gt_clocksource = {
-+ .name = "arm_global_timer",
-+ .rating = 300,
-+ .read = gt_clocksource_read,
-+ .mask = CLOCKSOURCE_MASK(64),
-+ .flags = CLOCK_SOURCE_IS_CONTINUOUS,
-+};
-+
-+#ifdef CONFIG_CLKSRC_ARM_GLOBAL_TIMER_SCHED_CLOCK
-+static u32 notrace gt_sched_clock_read(void)
-+{
-+ return gt_counter_read();
-+}
-+#endif
-+
-+static void __init gt_clocksource_init(void)
-+{
-+ writel(0, gt_base + GT_CONTROL);
-+ writel(0, gt_base + GT_COUNTER0);
-+ writel(0, gt_base + GT_COUNTER1);
-+ /* enables timer on all the cores */
-+ writel(GT_CONTROL_TIMER_ENABLE, gt_base + GT_CONTROL);
-+
-+#ifdef CONFIG_CLKSRC_ARM_GLOBAL_TIMER_SCHED_CLOCK
-+ setup_sched_clock(gt_sched_clock_read, 32, gt_clk_rate);
-+#endif
-+ clocksource_register_hz(>_clocksource, gt_clk_rate);
-+}
-+
-+static int __cpuinit gt_cpu_notify(struct notifier_block *self,
-+ unsigned long action, void *hcpu)
-+{
-+ switch (action & ~CPU_TASKS_FROZEN) {
-+ case CPU_STARTING:
-+ gt_clockevents_init(this_cpu_ptr(gt_evt));
-+ break;
-+ case CPU_DYING:
-+ gt_clockevents_stop(this_cpu_ptr(gt_evt));
-+ break;
-+ }
-+
-+ return NOTIFY_OK;
-+}
-+static struct notifier_block gt_cpu_nb __cpuinitdata = {
-+ .notifier_call = gt_cpu_notify,
-+};
-+
-+static void __init global_timer_of_register(struct device_node *np)
-+{
-+ struct clk *gt_clk;
-+ int err = 0;
-+
-+ /*
-+ * In r2p0 the comparators for each processor with the global timer
-+ * fire when the timer value is greater than or equal to. In previous
-+ * revisions the comparators fired when the timer value was equal to.
-+ */
-+ if ((read_cpuid_id() & 0xf0000f) < 0x200000) {
-+ pr_warn("global-timer: non support for this cpu version.\n");
-+ return;
-+ }
-+
-+ gt_ppi = irq_of_parse_and_map(np, 0);
-+ if (!gt_ppi) {
-+ pr_warn("global-timer: unable to parse irq\n");
-+ return;
-+ }
-+
-+ gt_base = of_iomap(np, 0);
-+ if (!gt_base) {
-+ pr_warn("global-timer: invalid base address\n");
-+ return;
-+ }
-+
-+ gt_clk = of_clk_get(np, 0);
-+ if (!IS_ERR(gt_clk)) {
-+ err = clk_prepare_enable(gt_clk);
-+ if (err)
-+ goto out_unmap;
-+ } else {
-+ pr_warn("global-timer: clk not found\n");
-+ err = -EINVAL;
-+ goto out_unmap;
-+ }
-+
-+ gt_clk_rate = clk_get_rate(gt_clk);
-+ gt_evt = alloc_percpu(struct clock_event_device);
-+ if (!gt_evt) {
-+ pr_warn("global-timer: can't allocate memory\n");
-+ err = -ENOMEM;
-+ goto out_clk;
-+ }
-+
-+ err = request_percpu_irq(gt_ppi, gt_clockevent_interrupt,
-+ "gt", gt_evt);
-+ if (err) {
-+ pr_warn("global-timer: can't register interrupt %d (%d)\n",
-+ gt_ppi, err);
-+ goto out_free;
-+ }
-+
-+ err = register_cpu_notifier(>_cpu_nb);
-+ if (err) {
-+ pr_warn("global-timer: unable to register cpu notifier.\n");
-+ goto out_irq;
-+ }
-+
-+ /* Immediately configure the timer on the boot CPU */
-+ gt_clocksource_init();
-+ gt_clockevents_init(this_cpu_ptr(gt_evt));
-+
-+ return;
-+
-+out_irq:
-+ free_percpu_irq(gt_ppi, gt_evt);
-+out_free:
-+ free_percpu(gt_evt);
-+out_clk:
-+ clk_disable_unprepare(gt_clk);
-+out_unmap:
-+ iounmap(gt_base);
-+ WARN(err, "ARM Global timer register failed (%d)\n", err);
-+}
-+
-+/* Only tested on r2p2 and r3p0 */
-+CLOCKSOURCE_OF_DECLARE(arm_gt, "arm,cortex-a9-global-timer",
-+ global_timer_of_register);
--- /dev/null
+From 5afd20a1eeef4db1d694d58931519f65e2003503 Mon Sep 17 00:00:00 2001
+From: Stuart Menefy <stuart.menefy@st.com>
+Date: Wed, 26 Jun 2013 12:48:38 +0100
+Subject: [PATCH 01/18] clocksource: arm_global_timer: Add ARM global timer
+ support
+
+This is a simple driver for the global timer module found in the Cortex
+A9-MP cores from revision r1p0 onwards. This should be able to perform
+the functions of the system timer and the local timer in an SMP system.
+
+The global timer has the following features:
+ The global timer is a 64-bit incrementing counter with an
+auto-incrementing feature. It continues incrementing after sending
+interrupts. The global timer is memory mapped in the private memory
+region.
+ The global timer is accessible to all Cortex-A9 processors in the
+cluster. Each Cortex-A9 processor has a private 64-bit comparator that
+is used to assert a private interrupt when the global timer has reached
+the comparator value. All the Cortex-A9 processors in a design use the
+banked ID, ID27, for this interrupt. ID27 is sent to the Interrupt
+Controller as a Private Peripheral Interrupt. The global timer is
+clocked by PERIPHCLK.
+
+Signed-off-by: Stuart Menefy <stuart.menefy@st.com>
+Signed-off-by: Srinivas Kandagatla <srinivas.kandagatla@st.com>
+CC: Arnd Bergmann <arnd@arndb.de>
+CC: Rob Herring <robherring2@gmail.com>
+CC: Linus Walleij <linus.walleij@linaro.org>
+CC: Will Deacon <will.deacon@arm.com>
+CC: Thomas Gleixner <tglx@linutronix.de>
+Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
+---
+ .../devicetree/bindings/arm/global_timer.txt | 24 ++
+ drivers/clocksource/Kconfig | 13 +
+ drivers/clocksource/Makefile | 1 +
+ drivers/clocksource/arm_global_timer.c | 321 ++++++++++++++++++++
+ 4 files changed, 359 insertions(+)
+ create mode 100644 Documentation/devicetree/bindings/arm/global_timer.txt
+ create mode 100644 drivers/clocksource/arm_global_timer.c
+
+--- /dev/null
++++ b/Documentation/devicetree/bindings/arm/global_timer.txt
+@@ -0,0 +1,24 @@
++
++* ARM Global Timer
++ Cortex-A9 are often associated with a per-core Global timer.
++
++** Timer node required properties:
++
++- compatible : Should be "arm,cortex-a9-global-timer"
++ Driver supports versions r2p0 and above.
++
++- interrupts : One interrupt to each core
++
++- reg : Specify the base address and the size of the GT timer
++ register window.
++
++- clocks : Should be phandle to a clock.
++
++Example:
++
++ timer@2c000600 {
++ compatible = "arm,cortex-a9-global-timer";
++ reg = <0x2c000600 0x20>;
++ interrupts = <1 13 0xf01>;
++ clocks = <&arm_periph_clk>;
++ };
+--- a/drivers/clocksource/Kconfig
++++ b/drivers/clocksource/Kconfig
+@@ -67,6 +67,19 @@ config ARM_ARCH_TIMER
+ bool
+ select CLKSRC_OF if OF
+
++config ARM_GLOBAL_TIMER
++ bool
++ select CLKSRC_OF if OF
++ help
++ This options enables support for the ARM global timer unit
++
++config CLKSRC_ARM_GLOBAL_TIMER_SCHED_CLOCK
++ bool
++ depends on ARM_GLOBAL_TIMER
++ default y
++ help
++ Use ARM global timer clock source as sched_clock
++
+ config CLKSRC_METAG_GENERIC
+ def_bool y if METAG
+ help
+--- a/drivers/clocksource/Makefile
++++ b/drivers/clocksource/Makefile
+@@ -28,4 +28,5 @@ obj-$(CONFIG_CLKSRC_EXYNOS_MCT) += exyno
+ obj-$(CONFIG_CLKSRC_SAMSUNG_PWM) += samsung_pwm_timer.o
+
+ obj-$(CONFIG_ARM_ARCH_TIMER) += arm_arch_timer.o
++obj-$(CONFIG_ARM_GLOBAL_TIMER) += arm_global_timer.o
+ obj-$(CONFIG_CLKSRC_METAG_GENERIC) += metag_generic.o
+--- /dev/null
++++ b/drivers/clocksource/arm_global_timer.c
+@@ -0,0 +1,321 @@
++/*
++ * drivers/clocksource/arm_global_timer.c
++ *
++ * Copyright (C) 2013 STMicroelectronics (R&D) Limited.
++ * Author: Stuart Menefy <stuart.menefy@st.com>
++ * Author: Srinivas Kandagatla <srinivas.kandagatla@st.com>
++ *
++ * This program is free software; you can redistribute it and/or modify
++ * it under the terms of the GNU General Public License version 2 as
++ * published by the Free Software Foundation.
++ */
++
++#include <linux/init.h>
++#include <linux/interrupt.h>
++#include <linux/clocksource.h>
++#include <linux/clockchips.h>
++#include <linux/cpu.h>
++#include <linux/clk.h>
++#include <linux/err.h>
++#include <linux/io.h>
++#include <linux/of.h>
++#include <linux/of_irq.h>
++#include <linux/of_address.h>
++#include <asm/sched_clock.h>
++
++#include <asm/cputype.h>
++
++#define GT_COUNTER0 0x00
++#define GT_COUNTER1 0x04
++
++#define GT_CONTROL 0x08
++#define GT_CONTROL_TIMER_ENABLE BIT(0) /* this bit is NOT banked */
++#define GT_CONTROL_COMP_ENABLE BIT(1) /* banked */
++#define GT_CONTROL_IRQ_ENABLE BIT(2) /* banked */
++#define GT_CONTROL_AUTO_INC BIT(3) /* banked */
++
++#define GT_INT_STATUS 0x0c
++#define GT_INT_STATUS_EVENT_FLAG BIT(0)
++
++#define GT_COMP0 0x10
++#define GT_COMP1 0x14
++#define GT_AUTO_INC 0x18
++
++/*
++ * We are expecting to be clocked by the ARM peripheral clock.
++ *
++ * Note: it is assumed we are using a prescaler value of zero, so this is
++ * the units for all operations.
++ */
++static void __iomem *gt_base;
++static unsigned long gt_clk_rate;
++static int gt_ppi;
++static struct clock_event_device __percpu *gt_evt;
++
++/*
++ * To get the value from the Global Timer Counter register proceed as follows:
++ * 1. Read the upper 32-bit timer counter register
++ * 2. Read the lower 32-bit timer counter register
++ * 3. Read the upper 32-bit timer counter register again. If the value is
++ * different to the 32-bit upper value read previously, go back to step 2.
++ * Otherwise the 64-bit timer counter value is correct.
++ */
++static u64 gt_counter_read(void)
++{
++ u64 counter;
++ u32 lower;
++ u32 upper, old_upper;
++
++ upper = readl_relaxed(gt_base + GT_COUNTER1);
++ do {
++ old_upper = upper;
++ lower = readl_relaxed(gt_base + GT_COUNTER0);
++ upper = readl_relaxed(gt_base + GT_COUNTER1);
++ } while (upper != old_upper);
++
++ counter = upper;
++ counter <<= 32;
++ counter |= lower;
++ return counter;
++}
++
++/**
++ * To ensure that updates to comparator value register do not set the
++ * Interrupt Status Register proceed as follows:
++ * 1. Clear the Comp Enable bit in the Timer Control Register.
++ * 2. Write the lower 32-bit Comparator Value Register.
++ * 3. Write the upper 32-bit Comparator Value Register.
++ * 4. Set the Comp Enable bit and, if necessary, the IRQ enable bit.
++ */
++static void gt_compare_set(unsigned long delta, int periodic)
++{
++ u64 counter = gt_counter_read();
++ unsigned long ctrl;
++
++ counter += delta;
++ ctrl = GT_CONTROL_TIMER_ENABLE;
++ writel(ctrl, gt_base + GT_CONTROL);
++ writel(lower_32_bits(counter), gt_base + GT_COMP0);
++ writel(upper_32_bits(counter), gt_base + GT_COMP1);
++
++ if (periodic) {
++ writel(delta, gt_base + GT_AUTO_INC);
++ ctrl |= GT_CONTROL_AUTO_INC;
++ }
++
++ ctrl |= GT_CONTROL_COMP_ENABLE | GT_CONTROL_IRQ_ENABLE;
++ writel(ctrl, gt_base + GT_CONTROL);
++}
++
++static void gt_clockevent_set_mode(enum clock_event_mode mode,
++ struct clock_event_device *clk)
++{
++ unsigned long ctrl;
++
++ switch (mode) {
++ case CLOCK_EVT_MODE_PERIODIC:
++ gt_compare_set(DIV_ROUND_CLOSEST(gt_clk_rate, HZ), 1);
++ break;
++ case CLOCK_EVT_MODE_ONESHOT:
++ case CLOCK_EVT_MODE_UNUSED:
++ case CLOCK_EVT_MODE_SHUTDOWN:
++ ctrl = readl(gt_base + GT_CONTROL);
++ ctrl &= ~(GT_CONTROL_COMP_ENABLE |
++ GT_CONTROL_IRQ_ENABLE | GT_CONTROL_AUTO_INC);
++ writel(ctrl, gt_base + GT_CONTROL);
++ break;
++ default:
++ break;
++ }
++}
++
++static int gt_clockevent_set_next_event(unsigned long evt,
++ struct clock_event_device *unused)
++{
++ gt_compare_set(evt, 0);
++ return 0;
++}
++
++static irqreturn_t gt_clockevent_interrupt(int irq, void *dev_id)
++{
++ struct clock_event_device *evt = dev_id;
++
++ if (!(readl_relaxed(gt_base + GT_INT_STATUS) &
++ GT_INT_STATUS_EVENT_FLAG))
++ return IRQ_NONE;
++
++ /**
++ * ERRATA 740657( Global Timer can send 2 interrupts for
++ * the same event in single-shot mode)
++ * Workaround:
++ * Either disable single-shot mode.
++ * Or
++ * Modify the Interrupt Handler to avoid the
++ * offending sequence. This is achieved by clearing
++ * the Global Timer flag _after_ having incremented
++ * the Comparator register value to a higher value.
++ */
++ if (evt->mode == CLOCK_EVT_MODE_ONESHOT)
++ gt_compare_set(ULONG_MAX, 0);
++
++ writel_relaxed(GT_INT_STATUS_EVENT_FLAG, gt_base + GT_INT_STATUS);
++ evt->event_handler(evt);
++
++ return IRQ_HANDLED;
++}
++
++static int __cpuinit gt_clockevents_init(struct clock_event_device *clk)
++{
++ int cpu = smp_processor_id();
++
++ clk->name = "arm_global_timer";
++ clk->features = CLOCK_EVT_FEAT_PERIODIC | CLOCK_EVT_FEAT_ONESHOT;
++ clk->set_mode = gt_clockevent_set_mode;
++ clk->set_next_event = gt_clockevent_set_next_event;
++ clk->cpumask = cpumask_of(cpu);
++ clk->rating = 300;
++ clk->irq = gt_ppi;
++ clockevents_config_and_register(clk, gt_clk_rate,
++ 1, 0xffffffff);
++ enable_percpu_irq(clk->irq, IRQ_TYPE_NONE);
++ return 0;
++}
++
++static void gt_clockevents_stop(struct clock_event_device *clk)
++{
++ gt_clockevent_set_mode(CLOCK_EVT_MODE_UNUSED, clk);
++ disable_percpu_irq(clk->irq);
++}
++
++static cycle_t gt_clocksource_read(struct clocksource *cs)
++{
++ return gt_counter_read();
++}
++
++static struct clocksource gt_clocksource = {
++ .name = "arm_global_timer",
++ .rating = 300,
++ .read = gt_clocksource_read,
++ .mask = CLOCKSOURCE_MASK(64),
++ .flags = CLOCK_SOURCE_IS_CONTINUOUS,
++};
++
++#ifdef CONFIG_CLKSRC_ARM_GLOBAL_TIMER_SCHED_CLOCK
++static u32 notrace gt_sched_clock_read(void)
++{
++ return gt_counter_read();
++}
++#endif
++
++static void __init gt_clocksource_init(void)
++{
++ writel(0, gt_base + GT_CONTROL);
++ writel(0, gt_base + GT_COUNTER0);
++ writel(0, gt_base + GT_COUNTER1);
++ /* enables timer on all the cores */
++ writel(GT_CONTROL_TIMER_ENABLE, gt_base + GT_CONTROL);
++
++#ifdef CONFIG_CLKSRC_ARM_GLOBAL_TIMER_SCHED_CLOCK
++ setup_sched_clock(gt_sched_clock_read, 32, gt_clk_rate);
++#endif
++ clocksource_register_hz(>_clocksource, gt_clk_rate);
++}
++
++static int __cpuinit gt_cpu_notify(struct notifier_block *self,
++ unsigned long action, void *hcpu)
++{
++ switch (action & ~CPU_TASKS_FROZEN) {
++ case CPU_STARTING:
++ gt_clockevents_init(this_cpu_ptr(gt_evt));
++ break;
++ case CPU_DYING:
++ gt_clockevents_stop(this_cpu_ptr(gt_evt));
++ break;
++ }
++
++ return NOTIFY_OK;
++}
++static struct notifier_block gt_cpu_nb __cpuinitdata = {
++ .notifier_call = gt_cpu_notify,
++};
++
++static void __init global_timer_of_register(struct device_node *np)
++{
++ struct clk *gt_clk;
++ int err = 0;
++
++ /*
++ * In r2p0 the comparators for each processor with the global timer
++ * fire when the timer value is greater than or equal to. In previous
++ * revisions the comparators fired when the timer value was equal to.
++ */
++ if ((read_cpuid_id() & 0xf0000f) < 0x200000) {
++ pr_warn("global-timer: non support for this cpu version.\n");
++ return;
++ }
++
++ gt_ppi = irq_of_parse_and_map(np, 0);
++ if (!gt_ppi) {
++ pr_warn("global-timer: unable to parse irq\n");
++ return;
++ }
++
++ gt_base = of_iomap(np, 0);
++ if (!gt_base) {
++ pr_warn("global-timer: invalid base address\n");
++ return;
++ }
++
++ gt_clk = of_clk_get(np, 0);
++ if (!IS_ERR(gt_clk)) {
++ err = clk_prepare_enable(gt_clk);
++ if (err)
++ goto out_unmap;
++ } else {
++ pr_warn("global-timer: clk not found\n");
++ err = -EINVAL;
++ goto out_unmap;
++ }
++
++ gt_clk_rate = clk_get_rate(gt_clk);
++ gt_evt = alloc_percpu(struct clock_event_device);
++ if (!gt_evt) {
++ pr_warn("global-timer: can't allocate memory\n");
++ err = -ENOMEM;
++ goto out_clk;
++ }
++
++ err = request_percpu_irq(gt_ppi, gt_clockevent_interrupt,
++ "gt", gt_evt);
++ if (err) {
++ pr_warn("global-timer: can't register interrupt %d (%d)\n",
++ gt_ppi, err);
++ goto out_free;
++ }
++
++ err = register_cpu_notifier(>_cpu_nb);
++ if (err) {
++ pr_warn("global-timer: unable to register cpu notifier.\n");
++ goto out_irq;
++ }
++
++ /* Immediately configure the timer on the boot CPU */
++ gt_clocksource_init();
++ gt_clockevents_init(this_cpu_ptr(gt_evt));
++
++ return;
++
++out_irq:
++ free_percpu_irq(gt_ppi, gt_evt);
++out_free:
++ free_percpu(gt_evt);
++out_clk:
++ clk_disable_unprepare(gt_clk);
++out_unmap:
++ iounmap(gt_base);
++ WARN(err, "ARM Global timer register failed (%d)\n", err);
++}
++
++/* Only tested on r2p2 and r3p0 */
++CLOCKSOURCE_OF_DECLARE(arm_gt, "arm,cortex-a9-global-timer",
++ global_timer_of_register);