diff options
Diffstat (limited to 'drivers')
| -rw-r--r-- | drivers/clocksource/Kconfig | 18 | ||||
| -rw-r--r-- | drivers/clocksource/Makefile | 2 | ||||
| -rw-r--r-- | drivers/clocksource/arm_global_timer.c | 321 | ||||
| -rw-r--r-- | drivers/clocksource/time-orion.c | 150 |
4 files changed, 491 insertions, 0 deletions
diff --git a/drivers/clocksource/Kconfig b/drivers/clocksource/Kconfig index 81465c21f873..b7b9b040a89b 100644 --- a/drivers/clocksource/Kconfig +++ b/drivers/clocksource/Kconfig @@ -27,6 +27,11 @@ 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 @@ -69,6 +74,19 @@ 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 9ba8b4d867e3..8b00c5cebfa4 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 @@ -30,5 +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 <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 <linux/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); 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 <sebastian.hesselbarth@gmail.com> + * + * 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 <linux/kernel.h> +#include <linux/bitops.h> +#include <linux/clk.h> +#include <linux/clockchips.h> +#include <linux/interrupt.h> +#include <linux/of_address.h> +#include <linux/of_irq.h> +#include <linux/spinlock.h> +#include <asm/sched_clock.h> + +#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); |