diff options
Diffstat (limited to 'drivers')
| -rw-r--r-- | drivers/clocksource/Kconfig | 5 | ||||
| -rw-r--r-- | drivers/clocksource/Makefile | 3 | ||||
| -rw-r--r-- | drivers/clocksource/exynos_mct.c | 556 |
3 files changed, 563 insertions, 1 deletions
diff --git a/drivers/clocksource/Kconfig b/drivers/clocksource/Kconfig index 3167fda9bbb..73fcddb8314 100644 --- a/drivers/clocksource/Kconfig +++ b/drivers/clocksource/Kconfig @@ -70,3 +70,8 @@ config CLKSRC_METAG_GENERIC def_bool y if METAG help This option enables support for the Meta per-thread timers. + +config CLKSRC_EXYNOS_MCT + def_bool y if ARCH_EXYNOS + help + Support for Multi Core Timer controller on Exynos SoCs. diff --git a/drivers/clocksource/Makefile b/drivers/clocksource/Makefile index e74c8ce26bf..cd1f09cbd61 100644 --- a/drivers/clocksource/Makefile +++ b/drivers/clocksource/Makefile @@ -19,7 +19,8 @@ obj-$(CONFIG_ARCH_BCM2835) += bcm2835_timer.o obj-$(CONFIG_SUNXI_TIMER) += sunxi_timer.o obj-$(CONFIG_ARCH_TEGRA) += tegra20_timer.o obj-$(CONFIG_VT8500_TIMER) += vt8500_timer.o -obj-$(CONFIG_CADENCE_TTC_TIMER) += cadence_ttc_timer.o +obj-$(CONFIG_CADENCE_TTC_TIMER) += cadence_ttc_timer.o +obj-$(CONFIG_CLKSRC_EXYNOS_MCT) += exynos_mct.o obj-$(CONFIG_ARM_ARCH_TIMER) += arm_arch_timer.o obj-$(CONFIG_CLKSRC_METAG_GENERIC) += metag_generic.o diff --git a/drivers/clocksource/exynos_mct.c b/drivers/clocksource/exynos_mct.c new file mode 100644 index 00000000000..957af8636c9 --- /dev/null +++ b/drivers/clocksource/exynos_mct.c @@ -0,0 +1,556 @@ +/* linux/arch/arm/mach-exynos4/mct.c + * + * Copyright (c) 2011 Samsung Electronics Co., Ltd. + * http://www.samsung.com + * + * EXYNOS4 MCT(Multi-Core Timer) support + * + * 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/sched.h> +#include <linux/interrupt.h> +#include <linux/irq.h> +#include <linux/err.h> +#include <linux/clk.h> +#include <linux/clockchips.h> +#include <linux/platform_device.h> +#include <linux/delay.h> +#include <linux/percpu.h> +#include <linux/of.h> +#include <linux/of_irq.h> +#include <linux/of_address.h> +#include <linux/clocksource.h> + +#include <asm/arch_timer.h> +#include <asm/localtimer.h> + +#include <plat/cpu.h> + +#include <mach/map.h> +#include <mach/irqs.h> +#include <asm/mach/time.h> + +#define EXYNOS4_MCTREG(x) (x) +#define EXYNOS4_MCT_G_CNT_L EXYNOS4_MCTREG(0x100) +#define EXYNOS4_MCT_G_CNT_U EXYNOS4_MCTREG(0x104) +#define EXYNOS4_MCT_G_CNT_WSTAT EXYNOS4_MCTREG(0x110) +#define EXYNOS4_MCT_G_COMP0_L EXYNOS4_MCTREG(0x200) +#define EXYNOS4_MCT_G_COMP0_U EXYNOS4_MCTREG(0x204) +#define EXYNOS4_MCT_G_COMP0_ADD_INCR EXYNOS4_MCTREG(0x208) +#define EXYNOS4_MCT_G_TCON EXYNOS4_MCTREG(0x240) +#define EXYNOS4_MCT_G_INT_CSTAT EXYNOS4_MCTREG(0x244) +#define EXYNOS4_MCT_G_INT_ENB EXYNOS4_MCTREG(0x248) +#define EXYNOS4_MCT_G_WSTAT EXYNOS4_MCTREG(0x24C) +#define _EXYNOS4_MCT_L_BASE EXYNOS4_MCTREG(0x300) +#define EXYNOS4_MCT_L_BASE(x) (_EXYNOS4_MCT_L_BASE + (0x100 * x)) +#define EXYNOS4_MCT_L_MASK (0xffffff00) + +#define MCT_L_TCNTB_OFFSET (0x00) +#define MCT_L_ICNTB_OFFSET (0x08) +#define MCT_L_TCON_OFFSET (0x20) +#define MCT_L_INT_CSTAT_OFFSET (0x30) +#define MCT_L_INT_ENB_OFFSET (0x34) +#define MCT_L_WSTAT_OFFSET (0x40) +#define MCT_G_TCON_START (1 << 8) +#define MCT_G_TCON_COMP0_AUTO_INC (1 << 1) +#define MCT_G_TCON_COMP0_ENABLE (1 << 0) +#define MCT_L_TCON_INTERVAL_MODE (1 << 2) +#define MCT_L_TCON_INT_START (1 << 1) +#define MCT_L_TCON_TIMER_START (1 << 0) + +#define TICK_BASE_CNT 1 + +enum { + MCT_INT_SPI, + MCT_INT_PPI +}; + +enum { + MCT_G0_IRQ, + MCT_G1_IRQ, + MCT_G2_IRQ, + MCT_G3_IRQ, + MCT_L0_IRQ, + MCT_L1_IRQ, + MCT_L2_IRQ, + MCT_L3_IRQ, + MCT_NR_IRQS, +}; + +static void __iomem *reg_base; +static unsigned long clk_rate; +static unsigned int mct_int_type; +static int mct_irqs[MCT_NR_IRQS]; + +struct mct_clock_event_device { + struct clock_event_device *evt; + unsigned long base; + char name[10]; +}; + +static void exynos4_mct_write(unsigned int value, unsigned long offset) +{ + unsigned long stat_addr; + u32 mask; + u32 i; + + __raw_writel(value, reg_base + offset); + + if (likely(offset >= EXYNOS4_MCT_L_BASE(0))) { + stat_addr = (offset & ~EXYNOS4_MCT_L_MASK) + MCT_L_WSTAT_OFFSET; + switch (offset & EXYNOS4_MCT_L_MASK) { + case MCT_L_TCON_OFFSET: + mask = 1 << 3; /* L_TCON write status */ + break; + case MCT_L_ICNTB_OFFSET: + mask = 1 << 1; /* L_ICNTB write status */ + break; + case MCT_L_TCNTB_OFFSET: + mask = 1 << 0; /* L_TCNTB write status */ + break; + default: + return; + } + } else { + switch (offset) { + case EXYNOS4_MCT_G_TCON: + stat_addr = EXYNOS4_MCT_G_WSTAT; + mask = 1 << 16; /* G_TCON write status */ + break; + case EXYNOS4_MCT_G_COMP0_L: + stat_addr = EXYNOS4_MCT_G_WSTAT; + mask = 1 << 0; /* G_COMP0_L write status */ + break; + case EXYNOS4_MCT_G_COMP0_U: + stat_addr = EXYNOS4_MCT_G_WSTAT; + mask = 1 << 1; /* G_COMP0_U write status */ + break; + case EXYNOS4_MCT_G_COMP0_ADD_INCR: + stat_addr = EXYNOS4_MCT_G_WSTAT; + mask = 1 << 2; /* G_COMP0_ADD_INCR w status */ + break; + case EXYNOS4_MCT_G_CNT_L: + stat_addr = EXYNOS4_MCT_G_CNT_WSTAT; + mask = 1 << 0; /* G_CNT_L write status */ + break; + case EXYNOS4_MCT_G_CNT_U: + stat_addr = EXYNOS4_MCT_G_CNT_WSTAT; + mask = 1 << 1; /* G_CNT_U write status */ + break; + default: + return; + } + } + + /* Wait maximum 1 ms until written values are applied */ + for (i = 0; i < loops_per_jiffy / 1000 * HZ; i++) + if (__raw_readl(reg_base + stat_addr) & mask) { + __raw_writel(mask, reg_base + stat_addr); + return; + } + + panic("MCT hangs after writing %d (offset:0x%lx)\n", value, offset); +} + +/* Clocksource handling */ +static void exynos4_mct_frc_start(u32 hi, u32 lo) +{ + u32 reg; + + exynos4_mct_write(lo, EXYNOS4_MCT_G_CNT_L); + exynos4_mct_write(hi, EXYNOS4_MCT_G_CNT_U); + + reg = __raw_readl(reg_base + EXYNOS4_MCT_G_TCON); + reg |= MCT_G_TCON_START; + exynos4_mct_write(reg, EXYNOS4_MCT_G_TCON); +} + +static cycle_t exynos4_frc_read(struct clocksource *cs) +{ + unsigned int lo, hi; + u32 hi2 = __raw_readl(reg_base + EXYNOS4_MCT_G_CNT_U); + + do { + hi = hi2; + lo = __raw_readl(reg_base + EXYNOS4_MCT_G_CNT_L); + hi2 = __raw_readl(reg_base + EXYNOS4_MCT_G_CNT_U); + } while (hi != hi2); + + return ((cycle_t)hi << 32) | lo; +} + +static void exynos4_frc_resume(struct clocksource *cs) +{ + exynos4_mct_frc_start(0, 0); +} + +struct clocksource mct_frc = { + .name = "mct-frc", + .rating = 400, + .read = exynos4_frc_read, + .mask = CLOCKSOURCE_MASK(64), + .flags = CLOCK_SOURCE_IS_CONTINUOUS, + .resume = exynos4_frc_resume, +}; + +static void __init exynos4_clocksource_init(void) +{ + exynos4_mct_frc_start(0, 0); + + if (clocksource_register_hz(&mct_frc, clk_rate)) + panic("%s: can't register clocksource\n", mct_frc.name); +} + +static void exynos4_mct_comp0_stop(void) +{ + unsigned int tcon; + + tcon = __raw_readl(reg_base + EXYNOS4_MCT_G_TCON); + tcon &= ~(MCT_G_TCON_COMP0_ENABLE | MCT_G_TCON_COMP0_AUTO_INC); + + exynos4_mct_write(tcon, EXYNOS4_MCT_G_TCON); + exynos4_mct_write(0, EXYNOS4_MCT_G_INT_ENB); +} + +static void exynos4_mct_comp0_start(enum clock_event_mode mode, + unsigned long cycles) +{ + unsigned int tcon; + cycle_t comp_cycle; + + tcon = __raw_readl(reg_base + EXYNOS4_MCT_G_TCON); + + if (mode == CLOCK_EVT_MODE_PERIODIC) { + tcon |= MCT_G_TCON_COMP0_AUTO_INC; + exynos4_mct_write(cycles, EXYNOS4_MCT_G_COMP0_ADD_INCR); + } + + comp_cycle = exynos4_frc_read(&mct_frc) + cycles; + exynos4_mct_write((u32)comp_cycle, EXYNOS4_MCT_G_COMP0_L); + exynos4_mct_write((u32)(comp_cycle >> 32), EXYNOS4_MCT_G_COMP0_U); + + exynos4_mct_write(0x1, EXYNOS4_MCT_G_INT_ENB); + + tcon |= MCT_G_TCON_COMP0_ENABLE; + exynos4_mct_write(tcon , EXYNOS4_MCT_G_TCON); +} + +static int exynos4_comp_set_next_event(unsigned long cycles, + struct clock_event_device *evt) +{ + exynos4_mct_comp0_start(evt->mode, cycles); + + return 0; +} + +static void exynos4_comp_set_mode(enum clock_event_mode mode, + struct clock_event_device *evt) +{ + unsigned long cycles_per_jiffy; + exynos4_mct_comp0_stop(); + + switch (mode) { + case CLOCK_EVT_MODE_PERIODIC: + cycles_per_jiffy = + (((unsigned long long) NSEC_PER_SEC / HZ * evt->mult) >> evt->shift); + exynos4_mct_comp0_start(mode, cycles_per_jiffy); + break; + + case CLOCK_EVT_MODE_ONESHOT: + case CLOCK_EVT_MODE_UNUSED: + case CLOCK_EVT_MODE_SHUTDOWN: + case CLOCK_EVT_MODE_RESUME: + break; + } +} + +static struct clock_event_device mct_comp_device = { + .name = "mct-comp", + .features = CLOCK_EVT_FEAT_PERIODIC | CLOCK_EVT_FEAT_ONESHOT, + .rating = 250, + .set_next_event = exynos4_comp_set_next_event, + .set_mode = exynos4_comp_set_mode, +}; + +static irqreturn_t exynos4_mct_comp_isr(int irq, void *dev_id) +{ + struct clock_event_device *evt = dev_id; + + exynos4_mct_write(0x1, EXYNOS4_MCT_G_INT_CSTAT); + + evt->event_handler(evt); + + return IRQ_HANDLED; +} + +static struct irqaction mct_comp_event_irq = { + .name = "mct_comp_irq", + .flags = IRQF_TIMER | IRQF_IRQPOLL, + .handler = exynos4_mct_comp_isr, + .dev_id = &mct_comp_device, +}; + +static void exynos4_clockevent_init(void) +{ + mct_comp_device.cpumask = cpumask_of(0); + clockevents_config_and_register(&mct_comp_device, clk_rate, + 0xf, 0xffffffff); + setup_irq(mct_irqs[MCT_G0_IRQ], &mct_comp_event_irq); +} + +#ifdef CONFIG_LOCAL_TIMERS + +static DEFINE_PER_CPU(struct mct_clock_event_device, percpu_mct_tick); + +/* Clock event handling */ +static void exynos4_mct_tick_stop(struct mct_clock_event_device *mevt) +{ + unsigned long tmp; + unsigned long mask = MCT_L_TCON_INT_START | MCT_L_TCON_TIMER_START; + unsigned long offset = mevt->base + MCT_L_TCON_OFFSET; + + tmp = __raw_readl(reg_base + offset); + if (tmp & mask) { + tmp &= ~mask; + exynos4_mct_write(tmp, offset); + } +} + +static void exynos4_mct_tick_start(unsigned long cycles, + struct mct_clock_event_device *mevt) +{ + unsigned long tmp; + + exynos4_mct_tick_stop(mevt); + + tmp = (1 << 31) | cycles; /* MCT_L_UPDATE_ICNTB */ + + /* update interrupt count buffer */ + exynos4_mct_write(tmp, mevt->base + MCT_L_ICNTB_OFFSET); + + /* enable MCT tick interrupt */ + exynos4_mct_write(0x1, mevt->base + MCT_L_INT_ENB_OFFSET); + + tmp = __raw_readl(reg_base + mevt->base + MCT_L_TCON_OFFSET); + tmp |= MCT_L_TCON_INT_START | MCT_L_TCON_TIMER_START | + MCT_L_TCON_INTERVAL_MODE; + exynos4_mct_write(tmp, mevt->base + MCT_L_TCON_OFFSET); +} + +static int exynos4_tick_set_next_event(unsigned long cycles, + struct clock_event_device *evt) +{ + struct mct_clock_event_device *mevt = this_cpu_ptr(&percpu_mct_tick); + + exynos4_mct_tick_start(cycles, mevt); + + return 0; +} + +static inline void exynos4_tick_set_mode(enum clock_event_mode mode, + struct clock_event_device *evt) +{ + struct mct_clock_event_device *mevt = this_cpu_ptr(&percpu_mct_tick); + unsigned long cycles_per_jiffy; + + exynos4_mct_tick_stop(mevt); + + switch (mode) { + case CLOCK_EVT_MODE_PERIODIC: + cycles_per_jiffy = + (((unsigned long long) NSEC_PER_SEC / HZ * evt->mult) >> evt->shift); + exynos4_mct_tick_start(cycles_per_jiffy, mevt); + break; + + case CLOCK_EVT_MODE_ONESHOT: + case CLOCK_EVT_MODE_UNUSED: + case CLOCK_EVT_MODE_SHUTDOWN: + case CLOCK_EVT_MODE_RESUME: + break; + } +} + +static int exynos4_mct_tick_clear(struct mct_clock_event_device *mevt) +{ + struct clock_event_device *evt = mevt->evt; + + /* + * This is for supporting oneshot mode. + * Mct would generate interrupt periodically + * without explicit stopping. + */ + if (evt->mode != CLOCK_EVT_MODE_PERIODIC) + exynos4_mct_tick_stop(mevt); + + /* Clear the MCT tick interrupt */ + if (__raw_readl(reg_base + mevt->base + MCT_L_INT_CSTAT_OFFSET) & 1) { + exynos4_mct_write(0x1, mevt->base + MCT_L_INT_CSTAT_OFFSET); + return 1; + } else { + return 0; + } +} + +static irqreturn_t exynos4_mct_tick_isr(int irq, void *dev_id) +{ + struct mct_clock_event_device *mevt = dev_id; + struct clock_event_device *evt = mevt->evt; + + exynos4_mct_tick_clear(mevt); + + evt->event_handler(evt); + + return IRQ_HANDLED; +} + +static struct irqaction mct_tick0_event_irq = { + .name = "mct_tick0_irq", + .flags = IRQF_TIMER | IRQF_NOBALANCING, + .handler = exynos4_mct_tick_isr, +}; + +static struct irqaction mct_tick1_event_irq = { + .name = "mct_tick1_irq", + .flags = IRQF_TIMER | IRQF_NOBALANCING, + .handler = exynos4_mct_tick_isr, +}; + +static int __cpuinit exynos4_local_timer_setup(struct clock_event_device *evt) +{ + struct mct_clock_event_device *mevt; + unsigned int cpu = smp_processor_id(); + + mevt = this_cpu_ptr(&percpu_mct_tick); + mevt->evt = evt; + + mevt->base = EXYNOS4_MCT_L_BASE(cpu); + sprintf(mevt->name, "mct_tick%d", cpu); + + evt->name = mevt->name; + evt->cpumask = cpumask_of(cpu); + evt->set_next_event = exynos4_tick_set_next_event; + evt->set_mode = exynos4_tick_set_mode; + evt->features = CLOCK_EVT_FEAT_PERIODIC | CLOCK_EVT_FEAT_ONESHOT; + evt->rating = 450; + clockevents_config_and_register(evt, clk_rate / (TICK_BASE_CNT + 1), + 0xf, 0x7fffffff); + + exynos4_mct_write(TICK_BASE_CNT, mevt->base + MCT_L_TCNTB_OFFSET); + + if (mct_int_type == MCT_INT_SPI) { + if (cpu == 0) { + mct_tick0_event_irq.dev_id = mevt; + evt->irq = mct_irqs[MCT_L0_IRQ]; + setup_irq(evt->irq, &mct_tick0_event_irq); + } else { + mct_tick1_event_irq.dev_id = mevt; + evt->irq = mct_irqs[MCT_L1_IRQ]; + setup_irq(evt->irq, &mct_tick1_event_irq); + irq_set_affinity(evt->irq, cpumask_of(1)); + } + } else { + enable_percpu_irq(mct_irqs[MCT_L0_IRQ], 0); + } + + return 0; +} + +static void exynos4_local_timer_stop(struct clock_event_device *evt) +{ + unsigned int cpu = smp_processor_id(); + evt->set_mode(CLOCK_EVT_MODE_UNUSED, evt); + if (mct_int_type == MCT_INT_SPI) + if (cpu == 0) + remove_irq(evt->irq, &mct_tick0_event_irq); + else + remove_irq(evt->irq, &mct_tick1_event_irq); + else + disable_percpu_irq(mct_irqs[MCT_L0_IRQ]); +} + +static struct local_timer_ops exynos4_mct_tick_ops __cpuinitdata = { + .setup = exynos4_local_timer_setup, + .stop = exynos4_local_timer_stop, +}; +#endif /* CONFIG_LOCAL_TIMERS */ + +static void __init exynos4_timer_resources(void __iomem *base) +{ + struct clk *mct_clk; + mct_clk = clk_get(NULL, "xtal"); + + clk_rate = clk_get_rate(mct_clk); + + reg_base = base; + if (!reg_base) + panic("%s: unable to ioremap mct address space\n", __func__); + +#ifdef CONFIG_LOCAL_TIMERS + if (mct_int_type == MCT_INT_PPI) { + int err; + + err = request_percpu_irq(mct_irqs[MCT_L0_IRQ], + exynos4_mct_tick_isr, "MCT", + &percpu_mct_tick); + WARN(err, "MCT: can't request IRQ %d (%d)\n", + mct_irqs[MCT_L0_IRQ], err); + } + + local_timer_register(&exynos4_mct_tick_ops); +#endif /* CONFIG_LOCAL_TIMERS */ +} + +void __init mct_init(void) +{ + if (soc_is_exynos4210()) { + mct_irqs[MCT_G0_IRQ] = EXYNOS4_IRQ_MCT_G0; + mct_irqs[MCT_L0_IRQ] = EXYNOS4_IRQ_MCT_L0; + mct_irqs[MCT_L1_IRQ] = EXYNOS4_IRQ_MCT_L1; + mct_int_type = MCT_INT_SPI; + } else { + panic("unable to determine mct controller type\n"); + } + + exynos4_timer_resources(S5P_VA_SYSTIMER); + exynos4_clocksource_init(); + exynos4_clockevent_init(); +} + +static void __init mct_init_dt(struct device_node *np, unsigned int int_type) +{ + u32 nr_irqs, i; + + mct_int_type = int_type; + + /* This driver uses only one global timer interrupt */ + mct_irqs[MCT_G0_IRQ] = irq_of_parse_and_map(np, MCT_G0_IRQ); + + /* + * Find out the number of local irqs specified. The local + * timer irqs are specified after the four global timer + * irqs are specified. + */ + nr_irqs = of_irq_count(np); + for (i = MCT_L0_IRQ; i < nr_irqs; i++) + mct_irqs[i] = irq_of_parse_and_map(np, i); + + exynos4_timer_resources(of_iomap(np, 0)); + exynos4_clocksource_init(); + exynos4_clockevent_init(); +} + + +static void __init mct_init_spi(struct device_node *np) +{ + return mct_init_dt(np, MCT_INT_SPI); +} + +static void __init mct_init_ppi(struct device_node *np) +{ + return mct_init_dt(np, MCT_INT_PPI); +} +CLOCKSOURCE_OF_DECLARE(exynos4210, "samsung,exynos4210-mct", mct_init_spi); +CLOCKSOURCE_OF_DECLARE(exynos4412, "samsung,exynos4412-mct", mct_init_ppi); |