| /* |
| * |
| * Copyright (C) 2007 Google, Inc. |
| * Copyright (c) 2009-2011, Code Aurora Forum. All rights reserved. |
| * |
| * 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/clocksource.h> |
| #include <linux/clockchips.h> |
| #include <linux/init.h> |
| #include <linux/interrupt.h> |
| #include <linux/irq.h> |
| #include <linux/io.h> |
| |
| #include <asm/mach/time.h> |
| #include <asm/hardware/gic.h> |
| #include <asm/localtimer.h> |
| #include <asm/sched_clock.h> |
| |
| #include <mach/msm_iomap.h> |
| #include <mach/cpu.h> |
| #include <mach/board.h> |
| |
| #define TIMER_MATCH_VAL 0x0000 |
| #define TIMER_COUNT_VAL 0x0004 |
| #define TIMER_ENABLE 0x0008 |
| #define TIMER_ENABLE_CLR_ON_MATCH_EN BIT(1) |
| #define TIMER_ENABLE_EN BIT(0) |
| #define TIMER_CLEAR 0x000C |
| #define DGT_CLK_CTL 0x0034 |
| #define DGT_CLK_CTL_DIV_4 0x3 |
| |
| #define GPT_HZ 32768 |
| |
| #define MSM_DGT_SHIFT 5 |
| |
| static void __iomem *event_base; |
| |
| static irqreturn_t msm_timer_interrupt(int irq, void *dev_id) |
| { |
| struct clock_event_device *evt = *(struct clock_event_device **)dev_id; |
| /* Stop the timer tick */ |
| if (evt->mode == CLOCK_EVT_MODE_ONESHOT) { |
| u32 ctrl = readl_relaxed(event_base + TIMER_ENABLE); |
| ctrl &= ~TIMER_ENABLE_EN; |
| writel_relaxed(ctrl, event_base + TIMER_ENABLE); |
| } |
| evt->event_handler(evt); |
| return IRQ_HANDLED; |
| } |
| |
| static int msm_timer_set_next_event(unsigned long cycles, |
| struct clock_event_device *evt) |
| { |
| u32 ctrl = readl_relaxed(event_base + TIMER_ENABLE); |
| |
| writel_relaxed(0, event_base + TIMER_CLEAR); |
| writel_relaxed(cycles, event_base + TIMER_MATCH_VAL); |
| writel_relaxed(ctrl | TIMER_ENABLE_EN, event_base + TIMER_ENABLE); |
| return 0; |
| } |
| |
| static void msm_timer_set_mode(enum clock_event_mode mode, |
| struct clock_event_device *evt) |
| { |
| u32 ctrl; |
| |
| ctrl = readl_relaxed(event_base + TIMER_ENABLE); |
| ctrl &= ~(TIMER_ENABLE_EN | TIMER_ENABLE_CLR_ON_MATCH_EN); |
| |
| switch (mode) { |
| case CLOCK_EVT_MODE_RESUME: |
| case CLOCK_EVT_MODE_PERIODIC: |
| break; |
| case CLOCK_EVT_MODE_ONESHOT: |
| /* Timer is enabled in set_next_event */ |
| break; |
| case CLOCK_EVT_MODE_UNUSED: |
| case CLOCK_EVT_MODE_SHUTDOWN: |
| break; |
| } |
| writel_relaxed(ctrl, event_base + TIMER_ENABLE); |
| } |
| |
| static struct clock_event_device msm_clockevent = { |
| .name = "gp_timer", |
| .features = CLOCK_EVT_FEAT_ONESHOT, |
| .rating = 200, |
| .set_next_event = msm_timer_set_next_event, |
| .set_mode = msm_timer_set_mode, |
| }; |
| |
| static union { |
| struct clock_event_device *evt; |
| struct clock_event_device __percpu **percpu_evt; |
| } msm_evt; |
| |
| static void __iomem *source_base; |
| |
| static notrace cycle_t msm_read_timer_count(struct clocksource *cs) |
| { |
| return readl_relaxed(source_base + TIMER_COUNT_VAL); |
| } |
| |
| static notrace cycle_t msm_read_timer_count_shift(struct clocksource *cs) |
| { |
| /* |
| * Shift timer count down by a constant due to unreliable lower bits |
| * on some targets. |
| */ |
| return msm_read_timer_count(cs) >> MSM_DGT_SHIFT; |
| } |
| |
| static struct clocksource msm_clocksource = { |
| .name = "dg_timer", |
| .rating = 300, |
| .read = msm_read_timer_count, |
| .mask = CLOCKSOURCE_MASK(32), |
| .flags = CLOCK_SOURCE_IS_CONTINUOUS, |
| }; |
| |
| #ifdef CONFIG_LOCAL_TIMERS |
| static int __cpuinit msm_local_timer_setup(struct clock_event_device *evt) |
| { |
| /* Use existing clock_event for cpu 0 */ |
| if (!smp_processor_id()) |
| return 0; |
| |
| writel_relaxed(0, event_base + TIMER_ENABLE); |
| writel_relaxed(0, event_base + TIMER_CLEAR); |
| writel_relaxed(~0, event_base + TIMER_MATCH_VAL); |
| evt->irq = msm_clockevent.irq; |
| evt->name = "local_timer"; |
| evt->features = msm_clockevent.features; |
| evt->rating = msm_clockevent.rating; |
| evt->set_mode = msm_timer_set_mode; |
| evt->set_next_event = msm_timer_set_next_event; |
| evt->shift = msm_clockevent.shift; |
| evt->mult = div_sc(GPT_HZ, NSEC_PER_SEC, evt->shift); |
| evt->max_delta_ns = clockevent_delta2ns(0xf0000000, evt); |
| evt->min_delta_ns = clockevent_delta2ns(4, evt); |
| |
| *__this_cpu_ptr(msm_evt.percpu_evt) = evt; |
| clockevents_register_device(evt); |
| enable_percpu_irq(evt->irq, IRQ_TYPE_EDGE_RISING); |
| return 0; |
| } |
| |
| static void msm_local_timer_stop(struct clock_event_device *evt) |
| { |
| evt->set_mode(CLOCK_EVT_MODE_UNUSED, evt); |
| disable_percpu_irq(evt->irq); |
| } |
| |
| static struct local_timer_ops msm_local_timer_ops __cpuinitdata = { |
| .setup = msm_local_timer_setup, |
| .stop = msm_local_timer_stop, |
| }; |
| #endif /* CONFIG_LOCAL_TIMERS */ |
| |
| static notrace u32 msm_sched_clock_read(void) |
| { |
| return msm_clocksource.read(&msm_clocksource); |
| } |
| |
| static void __init msm_timer_init(void) |
| { |
| struct clock_event_device *ce = &msm_clockevent; |
| struct clocksource *cs = &msm_clocksource; |
| int res; |
| u32 dgt_hz; |
| |
| if (cpu_is_msm7x01()) { |
| event_base = MSM_CSR_BASE; |
| source_base = MSM_CSR_BASE + 0x10; |
| dgt_hz = 19200000 >> MSM_DGT_SHIFT; /* 600 KHz */ |
| cs->read = msm_read_timer_count_shift; |
| cs->mask = CLOCKSOURCE_MASK((32 - MSM_DGT_SHIFT)); |
| } else if (cpu_is_msm7x30()) { |
| event_base = MSM_CSR_BASE + 0x04; |
| source_base = MSM_CSR_BASE + 0x24; |
| dgt_hz = 24576000 / 4; |
| } else if (cpu_is_qsd8x50()) { |
| event_base = MSM_CSR_BASE; |
| source_base = MSM_CSR_BASE + 0x10; |
| dgt_hz = 19200000 / 4; |
| } else if (cpu_is_msm8x60() || cpu_is_msm8960()) { |
| event_base = MSM_TMR_BASE + 0x04; |
| /* Use CPU0's timer as the global clock source. */ |
| source_base = MSM_TMR0_BASE + 0x24; |
| dgt_hz = 27000000 / 4; |
| writel_relaxed(DGT_CLK_CTL_DIV_4, MSM_TMR_BASE + DGT_CLK_CTL); |
| } else |
| BUG(); |
| |
| writel_relaxed(0, event_base + TIMER_ENABLE); |
| writel_relaxed(0, event_base + TIMER_CLEAR); |
| writel_relaxed(~0, event_base + TIMER_MATCH_VAL); |
| ce->cpumask = cpumask_of(0); |
| |
| ce->irq = INT_GP_TIMER_EXP; |
| clockevents_config_and_register(ce, GPT_HZ, 4, 0xffffffff); |
| if (cpu_is_msm8x60() || cpu_is_msm8960()) { |
| msm_evt.percpu_evt = alloc_percpu(struct clock_event_device *); |
| if (!msm_evt.percpu_evt) { |
| pr_err("memory allocation failed for %s\n", ce->name); |
| goto err; |
| } |
| *__this_cpu_ptr(msm_evt.percpu_evt) = ce; |
| res = request_percpu_irq(ce->irq, msm_timer_interrupt, |
| ce->name, msm_evt.percpu_evt); |
| if (!res) { |
| enable_percpu_irq(ce->irq, IRQ_TYPE_EDGE_RISING); |
| #ifdef CONFIG_LOCAL_TIMERS |
| local_timer_register(&msm_local_timer_ops); |
| #endif |
| } |
| } else { |
| msm_evt.evt = ce; |
| res = request_irq(ce->irq, msm_timer_interrupt, |
| IRQF_TIMER | IRQF_NOBALANCING | |
| IRQF_TRIGGER_RISING, ce->name, &msm_evt.evt); |
| } |
| |
| if (res) |
| pr_err("request_irq failed for %s\n", ce->name); |
| err: |
| writel_relaxed(TIMER_ENABLE_EN, source_base + TIMER_ENABLE); |
| res = clocksource_register_hz(cs, dgt_hz); |
| if (res) |
| pr_err("clocksource_register failed\n"); |
| setup_sched_clock(msm_sched_clock_read, |
| cpu_is_msm7x01() ? 32 - MSM_DGT_SHIFT : 32, dgt_hz); |
| } |
| |
| struct sys_timer msm_timer = { |
| .init = msm_timer_init |
| }; |