From: Hauke Mehrtens Date: Sun, 28 Jul 2013 21:22:50 +0000 (+0000) Subject: bcm53xx: use clocksource patch as it was committed upstream X-Git-Url: https://git.librecmc.org/?a=commitdiff_plain;h=333252e493edf46e9bd3a3915a91c67a775e6305;p=librecmc%2Flibrecmc.git bcm53xx: use clocksource patch as it was committed upstream Signed-off-by: Hauke Mehrtens SVN-Revision: 37585 --- diff --git a/target/linux/bcm53xx/patches-3.10/0001-clocksource-arm_global_timer-Add-ARM-global-timer-su.patch b/target/linux/bcm53xx/patches-3.10/0001-clocksource-arm_global_timer-Add-ARM-global-timer-su.patch deleted file mode 100644 index 90c117880a..0000000000 --- a/target/linux/bcm53xx/patches-3.10/0001-clocksource-arm_global_timer-Add-ARM-global-timer-su.patch +++ /dev/null @@ -1,421 +0,0 @@ -From 403eb25e5ae7a2169d8c1eae9df4162815e7c3ba Mon Sep 17 00:00:00 2001 -From: Stuart Menefy -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 -Signed-off-by: Srinivas Kandagatla -CC: Arnd Bergmann -CC: Rob Herring -CC: Linus Walleij -CC: Will Deacon -CC: Thomas Gleixner ---- - .../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 -+ * Author: Srinivas Kandagatla -+ * -+ * 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 -+#include -+#include -+#include -+#include -+#include -+#include -+#include -+#include -+#include -+#include -+ -+#include -+#include -+ -+#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); diff --git a/target/linux/bcm53xx/patches-3.10/001-clocksource-arm_global_timer-Add-ARM-global-timer-su.patch b/target/linux/bcm53xx/patches-3.10/001-clocksource-arm_global_timer-Add-ARM-global-timer-su.patch new file mode 100644 index 0000000000..3182b9c596 --- /dev/null +++ b/target/linux/bcm53xx/patches-3.10/001-clocksource-arm_global_timer-Add-ARM-global-timer-su.patch @@ -0,0 +1,421 @@ +From 5afd20a1eeef4db1d694d58931519f65e2003503 Mon Sep 17 00:00:00 2001 +From: Stuart Menefy +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 +Signed-off-by: Srinivas Kandagatla +CC: Arnd Bergmann +CC: Rob Herring +CC: Linus Walleij +CC: Will Deacon +CC: Thomas Gleixner +Signed-off-by: Daniel Lezcano +--- + .../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 ++ * Author: Srinivas Kandagatla ++ * ++ * 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 ++#include ++#include ++#include ++#include ++#include ++#include ++#include ++#include ++#include ++#include ++#include ++ ++#include ++ ++#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);