| /* linux/arch/arm/mach-msm/timer.c |
| * |
| * Copyright (C) 2007 Google, Inc. |
| * |
| * This software is licensed under the terms of the GNU General Public |
| * License version 2, as published by the Free Software Foundation, and |
| * may be copied, distributed, and modified under those terms. |
| * |
| * This program is distributed in the hope that it will be useful, |
| * but WITHOUT ANY WARRANTY; without even the implied warranty of |
| * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
| * GNU General Public License for more details. |
| * |
| */ |
| |
| #include <linux/init.h> |
| #include <linux/time.h> |
| #include <linux/interrupt.h> |
| #include <linux/irq.h> |
| #include <linux/clk.h> |
| #include <linux/clockchips.h> |
| #include <linux/delay.h> |
| #include <linux/io.h> |
| |
| #include <asm/mach/time.h> |
| #include <asm/hardware/gic.h> |
| |
| #include <mach/msm_iomap.h> |
| #include <mach/cpu.h> |
| |
| #define TIMER_MATCH_VAL 0x0000 |
| #define TIMER_COUNT_VAL 0x0004 |
| #define TIMER_ENABLE 0x0008 |
| #define TIMER_ENABLE_CLR_ON_MATCH_EN 2 |
| #define TIMER_ENABLE_EN 1 |
| #define TIMER_CLEAR 0x000C |
| #define DGT_CLK_CTL 0x0034 |
| enum { |
| DGT_CLK_CTL_DIV_1 = 0, |
| DGT_CLK_CTL_DIV_2 = 1, |
| DGT_CLK_CTL_DIV_3 = 2, |
| DGT_CLK_CTL_DIV_4 = 3, |
| }; |
| #define CSR_PROTECTION 0x0020 |
| #define CSR_PROTECTION_EN 1 |
| |
| #define GPT_HZ 32768 |
| |
| enum timer_location { |
| LOCAL_TIMER = 0, |
| GLOBAL_TIMER = 1, |
| }; |
| |
| #define MSM_GLOBAL_TIMER MSM_CLOCK_DGT |
| |
| /* TODO: Remove these ifdefs */ |
| #if defined(CONFIG_ARCH_QSD8X50) |
| #define DGT_HZ (19200000 / 4) /* 19.2 MHz / 4 by default */ |
| #define MSM_DGT_SHIFT (0) |
| #elif defined(CONFIG_ARCH_MSM7X30) |
| #define DGT_HZ (24576000 / 4) /* 24.576 MHz (LPXO) / 4 by default */ |
| #define MSM_DGT_SHIFT (0) |
| #elif defined(CONFIG_ARCH_MSM8X60) || defined(CONFIG_ARCH_MSM8960) |
| #define DGT_HZ (27000000 / 4) /* 27 MHz (PXO) / 4 by default */ |
| #define MSM_DGT_SHIFT (0) |
| #else |
| #define DGT_HZ 19200000 /* 19.2 MHz or 600 KHz after shift */ |
| #define MSM_DGT_SHIFT (5) |
| #endif |
| |
| struct msm_clock { |
| struct clock_event_device clockevent; |
| struct clocksource clocksource; |
| struct irqaction irq; |
| void __iomem *regbase; |
| uint32_t freq; |
| uint32_t shift; |
| void __iomem *global_counter; |
| void __iomem *local_counter; |
| }; |
| |
| enum { |
| MSM_CLOCK_GPT, |
| MSM_CLOCK_DGT, |
| NR_TIMERS, |
| }; |
| |
| |
| static struct msm_clock msm_clocks[]; |
| static struct clock_event_device *local_clock_event; |
| |
| static irqreturn_t msm_timer_interrupt(int irq, void *dev_id) |
| { |
| struct clock_event_device *evt = dev_id; |
| if (smp_processor_id() != 0) |
| evt = local_clock_event; |
| if (evt->event_handler == NULL) |
| return IRQ_HANDLED; |
| evt->event_handler(evt); |
| return IRQ_HANDLED; |
| } |
| |
| static cycle_t msm_read_timer_count(struct clocksource *cs) |
| { |
| struct msm_clock *clk = container_of(cs, struct msm_clock, clocksource); |
| |
| /* |
| * Shift timer count down by a constant due to unreliable lower bits |
| * on some targets. |
| */ |
| return readl(clk->global_counter) >> clk->shift; |
| } |
| |
| static struct msm_clock *clockevent_to_clock(struct clock_event_device *evt) |
| { |
| #ifdef CONFIG_SMP |
| int i; |
| for (i = 0; i < NR_TIMERS; i++) |
| if (evt == &(msm_clocks[i].clockevent)) |
| return &msm_clocks[i]; |
| return &msm_clocks[MSM_GLOBAL_TIMER]; |
| #else |
| return container_of(evt, struct msm_clock, clockevent); |
| #endif |
| } |
| |
| static int msm_timer_set_next_event(unsigned long cycles, |
| struct clock_event_device *evt) |
| { |
| struct msm_clock *clock = clockevent_to_clock(evt); |
| uint32_t now = readl(clock->local_counter); |
| uint32_t alarm = now + (cycles << clock->shift); |
| |
| writel(alarm, clock->regbase + TIMER_MATCH_VAL); |
| return 0; |
| } |
| |
| static void msm_timer_set_mode(enum clock_event_mode mode, |
| struct clock_event_device *evt) |
| { |
| struct msm_clock *clock = clockevent_to_clock(evt); |
| |
| switch (mode) { |
| case CLOCK_EVT_MODE_RESUME: |
| case CLOCK_EVT_MODE_PERIODIC: |
| break; |
| case CLOCK_EVT_MODE_ONESHOT: |
| writel(TIMER_ENABLE_EN, clock->regbase + TIMER_ENABLE); |
| break; |
| case CLOCK_EVT_MODE_UNUSED: |
| case CLOCK_EVT_MODE_SHUTDOWN: |
| writel(0, clock->regbase + TIMER_ENABLE); |
| break; |
| } |
| } |
| |
| static struct msm_clock msm_clocks[] = { |
| [MSM_CLOCK_GPT] = { |
| .clockevent = { |
| .name = "gp_timer", |
| .features = CLOCK_EVT_FEAT_ONESHOT, |
| .shift = 32, |
| .rating = 200, |
| .set_next_event = msm_timer_set_next_event, |
| .set_mode = msm_timer_set_mode, |
| }, |
| .clocksource = { |
| .name = "gp_timer", |
| .rating = 200, |
| .read = msm_read_timer_count, |
| .mask = CLOCKSOURCE_MASK(32), |
| .flags = CLOCK_SOURCE_IS_CONTINUOUS, |
| }, |
| .irq = { |
| .name = "gp_timer", |
| .flags = IRQF_DISABLED | IRQF_TIMER | IRQF_TRIGGER_RISING, |
| .handler = msm_timer_interrupt, |
| .dev_id = &msm_clocks[0].clockevent, |
| .irq = INT_GP_TIMER_EXP |
| }, |
| .freq = GPT_HZ, |
| }, |
| [MSM_CLOCK_DGT] = { |
| .clockevent = { |
| .name = "dg_timer", |
| .features = CLOCK_EVT_FEAT_ONESHOT, |
| .shift = 32 + MSM_DGT_SHIFT, |
| .rating = 300, |
| .set_next_event = msm_timer_set_next_event, |
| .set_mode = msm_timer_set_mode, |
| }, |
| .clocksource = { |
| .name = "dg_timer", |
| .rating = 300, |
| .read = msm_read_timer_count, |
| .mask = CLOCKSOURCE_MASK((32 - MSM_DGT_SHIFT)), |
| .flags = CLOCK_SOURCE_IS_CONTINUOUS, |
| }, |
| .irq = { |
| .name = "dg_timer", |
| .flags = IRQF_DISABLED | IRQF_TIMER | IRQF_TRIGGER_RISING, |
| .handler = msm_timer_interrupt, |
| .dev_id = &msm_clocks[1].clockevent, |
| .irq = INT_DEBUG_TIMER_EXP |
| }, |
| .freq = DGT_HZ >> MSM_DGT_SHIFT, |
| .shift = MSM_DGT_SHIFT, |
| } |
| }; |
| |
| static void __init msm_timer_init(void) |
| { |
| int i; |
| int res; |
| int global_offset = 0; |
| |
| if (cpu_is_msm7x01()) { |
| msm_clocks[MSM_CLOCK_GPT].regbase = MSM_CSR_BASE; |
| msm_clocks[MSM_CLOCK_DGT].regbase = MSM_CSR_BASE + 0x10; |
| } else if (cpu_is_msm7x30()) { |
| msm_clocks[MSM_CLOCK_GPT].regbase = MSM_CSR_BASE + 0x04; |
| msm_clocks[MSM_CLOCK_DGT].regbase = MSM_CSR_BASE + 0x24; |
| } else if (cpu_is_qsd8x50()) { |
| msm_clocks[MSM_CLOCK_GPT].regbase = MSM_CSR_BASE; |
| msm_clocks[MSM_CLOCK_DGT].regbase = MSM_CSR_BASE + 0x10; |
| } else if (cpu_is_msm8x60() || cpu_is_msm8960()) { |
| msm_clocks[MSM_CLOCK_GPT].regbase = MSM_TMR_BASE + 0x04; |
| msm_clocks[MSM_CLOCK_DGT].regbase = MSM_TMR_BASE + 0x24; |
| |
| /* Use CPU0's timer as the global timer. */ |
| global_offset = MSM_TMR0_BASE - MSM_TMR_BASE; |
| } else |
| BUG(); |
| |
| #ifdef CONFIG_ARCH_MSM_SCORPIONMP |
| writel(DGT_CLK_CTL_DIV_4, MSM_TMR_BASE + DGT_CLK_CTL); |
| #endif |
| |
| for (i = 0; i < ARRAY_SIZE(msm_clocks); i++) { |
| struct msm_clock *clock = &msm_clocks[i]; |
| struct clock_event_device *ce = &clock->clockevent; |
| struct clocksource *cs = &clock->clocksource; |
| |
| clock->local_counter = clock->regbase + TIMER_COUNT_VAL; |
| clock->global_counter = clock->local_counter + global_offset; |
| |
| writel(0, clock->regbase + TIMER_ENABLE); |
| writel(0, clock->regbase + TIMER_CLEAR); |
| writel(~0, clock->regbase + TIMER_MATCH_VAL); |
| |
| ce->mult = div_sc(clock->freq, NSEC_PER_SEC, ce->shift); |
| /* allow at least 10 seconds to notice that the timer wrapped */ |
| ce->max_delta_ns = |
| clockevent_delta2ns(0xf0000000 >> clock->shift, ce); |
| /* 4 gets rounded down to 3 */ |
| ce->min_delta_ns = clockevent_delta2ns(4, ce); |
| ce->cpumask = cpumask_of(0); |
| |
| res = clocksource_register_hz(cs, clock->freq); |
| if (res) |
| printk(KERN_ERR "msm_timer_init: clocksource_register " |
| "failed for %s\n", cs->name); |
| |
| res = setup_irq(clock->irq.irq, &clock->irq); |
| if (res) |
| printk(KERN_ERR "msm_timer_init: setup_irq " |
| "failed for %s\n", cs->name); |
| |
| clockevents_register_device(ce); |
| } |
| } |
| |
| #ifdef CONFIG_SMP |
| int __cpuinit local_timer_setup(struct clock_event_device *evt) |
| { |
| struct msm_clock *clock = &msm_clocks[MSM_GLOBAL_TIMER]; |
| |
| /* Use existing clock_event for cpu 0 */ |
| if (!smp_processor_id()) |
| return 0; |
| |
| writel(DGT_CLK_CTL_DIV_4, MSM_TMR_BASE + DGT_CLK_CTL); |
| |
| if (!local_clock_event) { |
| writel(0, clock->regbase + TIMER_ENABLE); |
| writel(0, clock->regbase + TIMER_CLEAR); |
| writel(~0, clock->regbase + TIMER_MATCH_VAL); |
| } |
| evt->irq = clock->irq.irq; |
| evt->name = "local_timer"; |
| evt->features = CLOCK_EVT_FEAT_ONESHOT; |
| evt->rating = clock->clockevent.rating; |
| evt->set_mode = msm_timer_set_mode; |
| evt->set_next_event = msm_timer_set_next_event; |
| evt->shift = clock->clockevent.shift; |
| evt->mult = div_sc(clock->freq, NSEC_PER_SEC, evt->shift); |
| evt->max_delta_ns = |
| clockevent_delta2ns(0xf0000000 >> clock->shift, evt); |
| evt->min_delta_ns = clockevent_delta2ns(4, evt); |
| |
| local_clock_event = evt; |
| |
| gic_enable_ppi(clock->irq.irq); |
| |
| clockevents_register_device(evt); |
| return 0; |
| } |
| |
| inline int local_timer_ack(void) |
| { |
| return 1; |
| } |
| |
| #endif |
| |
| struct sys_timer msm_timer = { |
| .init = msm_timer_init |
| }; |