From 0c1dcfd53b1066c411d3885cf8156abf59694360 Mon Sep 17 00:00:00 2001 From: Sebastian Hesselbarth Date: Tue, 11 Jun 2013 08:38:50 +0200 Subject: clocksource: Add Marvell Orion SoC timer This patch add a DT enabled driver for timers found on Marvell Orion SoCs (Kirkwood, Dove, Orion5x, and Discovery Innovation). It installs a free- running clocksource on timer0 and a clockevent source on timer1. Corresponding device tree documentation is also added. Signed-off-by: Sebastian Hesselbarth Signed-off-by: Daniel Lezcano Tested-by: Ezequiel Garcia Tested-by: Andrew Lunn --- drivers/clocksource/Kconfig | 5 ++ drivers/clocksource/Makefile | 1 + drivers/clocksource/time-orion.c | 150 +++++++++++++++++++++++++++++++++++++++ 3 files changed, 156 insertions(+) create mode 100644 drivers/clocksource/time-orion.c (limited to 'drivers/clocksource') diff --git a/drivers/clocksource/Kconfig b/drivers/clocksource/Kconfig index 0a04257edf65..c082e3e4bd0a 100644 --- a/drivers/clocksource/Kconfig +++ b/drivers/clocksource/Kconfig @@ -25,6 +25,11 @@ config DW_APB_TIMER_OF config ARMADA_370_XP_TIMER bool +config ORION_TIMER + select CLKSRC_OF + select CLKSRC_MMIO + bool + config SUN4I_TIMER bool diff --git a/drivers/clocksource/Makefile b/drivers/clocksource/Makefile index 9ba8b4d867e3..49bea7fad85c 100644 --- a/drivers/clocksource/Makefile +++ b/drivers/clocksource/Makefile @@ -15,6 +15,7 @@ obj-$(CONFIG_DW_APB_TIMER_OF) += dw_apb_timer_of.o obj-$(CONFIG_CLKSRC_NOMADIK_MTU) += nomadik-mtu.o obj-$(CONFIG_CLKSRC_DBX500_PRCMU) += clksrc-dbx500-prcmu.o obj-$(CONFIG_ARMADA_370_XP_TIMER) += time-armada-370-xp.o +obj-$(CONFIG_ORION_TIMER) += time-orion.o obj-$(CONFIG_ARCH_BCM2835) += bcm2835_timer.o obj-$(CONFIG_ARCH_MARCO) += timer-marco.o obj-$(CONFIG_ARCH_MXS) += mxs_timer.o diff --git a/drivers/clocksource/time-orion.c b/drivers/clocksource/time-orion.c new file mode 100644 index 000000000000..ecbeb6810215 --- /dev/null +++ b/drivers/clocksource/time-orion.c @@ -0,0 +1,150 @@ +/* + * Marvell Orion SoC timer handling. + * + * Sebastian Hesselbarth + * + * This file is licensed under the terms of the GNU General Public + * License version 2. This program is licensed "as is" without any + * warranty of any kind, whether express or implied. + * + * Timer 0 is used as free-running clocksource, while timer 1 is + * used as clock_event_device. + */ + +#include +#include +#include +#include +#include +#include +#include +#include +#include + +#define TIMER_CTRL 0x00 +#define TIMER0_EN BIT(0) +#define TIMER0_RELOAD_EN BIT(1) +#define TIMER1_EN BIT(2) +#define TIMER1_RELOAD_EN BIT(3) +#define TIMER0_RELOAD 0x10 +#define TIMER0_VAL 0x14 +#define TIMER1_RELOAD 0x18 +#define TIMER1_VAL 0x1c + +#define ORION_ONESHOT_MIN 1 +#define ORION_ONESHOT_MAX 0xfffffffe + +static void __iomem *timer_base; +static DEFINE_SPINLOCK(timer_ctrl_lock); + +/* + * Thread-safe access to TIMER_CTRL register + * (shared with watchdog timer) + */ +void orion_timer_ctrl_clrset(u32 clr, u32 set) +{ + spin_lock(&timer_ctrl_lock); + writel((readl(timer_base + TIMER_CTRL) & ~clr) | set, + timer_base + TIMER_CTRL); + spin_unlock(&timer_ctrl_lock); +} +EXPORT_SYMBOL(orion_timer_ctrl_clrset); + +/* + * Free-running clocksource handling. + */ +static u32 notrace orion_read_sched_clock(void) +{ + return ~readl(timer_base + TIMER0_VAL); +} + +/* + * Clockevent handling. + */ +static u32 ticks_per_jiffy; + +static int orion_clkevt_next_event(unsigned long delta, + struct clock_event_device *dev) +{ + /* setup and enable one-shot timer */ + writel(delta, timer_base + TIMER1_VAL); + orion_timer_ctrl_clrset(TIMER1_RELOAD_EN, TIMER1_EN); + + return 0; +} + +static void orion_clkevt_mode(enum clock_event_mode mode, + struct clock_event_device *dev) +{ + if (mode == CLOCK_EVT_MODE_PERIODIC) { + /* setup and enable periodic timer at 1/HZ intervals */ + writel(ticks_per_jiffy - 1, timer_base + TIMER1_RELOAD); + writel(ticks_per_jiffy - 1, timer_base + TIMER1_VAL); + orion_timer_ctrl_clrset(0, TIMER1_RELOAD_EN | TIMER1_EN); + } else { + /* disable timer */ + orion_timer_ctrl_clrset(TIMER1_RELOAD_EN | TIMER1_EN, 0); + } +} + +static struct clock_event_device orion_clkevt = { + .name = "orion_event", + .features = CLOCK_EVT_FEAT_ONESHOT | CLOCK_EVT_FEAT_PERIODIC, + .shift = 32, + .rating = 300, + .set_next_event = orion_clkevt_next_event, + .set_mode = orion_clkevt_mode, +}; + +static irqreturn_t orion_clkevt_irq_handler(int irq, void *dev_id) +{ + orion_clkevt.event_handler(&orion_clkevt); + return IRQ_HANDLED; +} + +static struct irqaction orion_clkevt_irq = { + .name = "orion_event", + .flags = IRQF_TIMER, + .handler = orion_clkevt_irq_handler, +}; + +static void __init orion_timer_init(struct device_node *np) +{ + struct clk *clk; + int irq; + + /* timer registers are shared with watchdog timer */ + timer_base = of_iomap(np, 0); + if (!timer_base) + panic("%s: unable to map resource\n", np->name); + + clk = of_clk_get(np, 0); + if (IS_ERR(clk)) + panic("%s: unable to get clk\n", np->name); + clk_prepare_enable(clk); + + /* we are only interested in timer1 irq */ + irq = irq_of_parse_and_map(np, 1); + if (irq <= 0) + panic("%s: unable to parse timer1 irq\n", np->name); + + /* setup timer0 as free-running clocksource */ + writel(~0, timer_base + TIMER0_VAL); + writel(~0, timer_base + TIMER0_RELOAD); + orion_timer_ctrl_clrset(0, TIMER0_RELOAD_EN | TIMER0_EN); + clocksource_mmio_init(timer_base + TIMER0_VAL, "orion_clocksource", + clk_get_rate(clk), 300, 32, + clocksource_mmio_readl_down); + setup_sched_clock(orion_read_sched_clock, 32, clk_get_rate(clk)); + + /* setup timer1 as clockevent timer */ + if (setup_irq(irq, &orion_clkevt_irq)) + panic("%s: unable to setup irq\n", np->name); + + ticks_per_jiffy = (clk_get_rate(clk) + HZ/2) / HZ; + orion_clkevt.cpumask = cpumask_of(0); + orion_clkevt.irq = irq; + clockevents_config_and_register(&orion_clkevt, clk_get_rate(clk), + ORION_ONESHOT_MIN, ORION_ONESHOT_MAX); +} +CLOCKSOURCE_OF_DECLARE(orion_timer, "marvell,orion-timer", orion_timer_init); -- cgit v1.2.1 From c1b40e447af8695666d4c11cfec4a7407e6a124d Mon Sep 17 00:00:00 2001 From: Stuart Menefy Date: Wed, 26 Jun 2013 12:48:38 +0100 Subject: 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 --- drivers/clocksource/Kconfig | 13 ++ drivers/clocksource/Makefile | 1 + drivers/clocksource/arm_global_timer.c | 321 +++++++++++++++++++++++++++++++++ 3 files changed, 335 insertions(+) create mode 100644 drivers/clocksource/arm_global_timer.c (limited to 'drivers/clocksource') diff --git a/drivers/clocksource/Kconfig b/drivers/clocksource/Kconfig index c082e3e4bd0a..42c8eccb1e86 100644 --- a/drivers/clocksource/Kconfig +++ b/drivers/clocksource/Kconfig @@ -72,6 +72,19 @@ 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 diff --git a/drivers/clocksource/Makefile b/drivers/clocksource/Makefile index 49bea7fad85c..8b00c5cebfa4 100644 --- a/drivers/clocksource/Makefile +++ b/drivers/clocksource/Makefile @@ -31,5 +31,6 @@ obj-$(CONFIG_CLKSRC_SAMSUNG_PWM) += samsung_pwm_timer.o obj-$(CONFIG_VF_PIT_TIMER) += vf_pit_timer.o obj-$(CONFIG_ARM_ARCH_TIMER) += arm_arch_timer.o +obj-$(CONFIG_ARM_GLOBAL_TIMER) += arm_global_timer.o obj-$(CONFIG_CLKSRC_METAG_GENERIC) += metag_generic.o obj-$(CONFIG_ARCH_HAS_TICK_BROADCAST) += dummy_timer.o diff --git a/drivers/clocksource/arm_global_timer.c b/drivers/clocksource/arm_global_timer.c new file mode 100644 index 000000000000..db8afc7427a6 --- /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); -- cgit v1.2.1