/* * * Copyright (C) 2007 Google, Inc. * Copyright (c) 2009-2012,2014, The Linux Foundation. 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/cpu.h>#include <linux/init.h>#include <linux/interrupt.h>#include <linux/irq.h>#include <linux/io.h>#include <linux/of.h>#include <linux/of_address.h>#include <linux/of_irq.h>#include <linux/sched_clock.h> #include <asm/delay.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			0x10#define DGT_CLK_CTL_DIV_4		0x3#define TIMER_STS_GPT0_CLR_PEND		BIT(10) #define GPT_HZ 32768 static void __iomem *event_base;static void __iomem *sts_base; static irqreturn_t msm_timer_interrupt(int irq, void *dev_id){	struct clock_event_device *evt = dev_id;	/* Stop the timer tick */	if (clockevent_state_oneshot(evt)) {		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); 	ctrl &= ~TIMER_ENABLE_EN;	writel_relaxed(ctrl, event_base + TIMER_ENABLE); 	writel_relaxed(ctrl, event_base + TIMER_CLEAR);	writel_relaxed(cycles, event_base + TIMER_MATCH_VAL); 	if (sts_base)		while (readl_relaxed(sts_base) & TIMER_STS_GPT0_CLR_PEND)			cpu_relax(); 	writel_relaxed(ctrl | TIMER_ENABLE_EN, event_base + TIMER_ENABLE);	return 0;} static int msm_timer_shutdown(struct clock_event_device *evt){	u32 ctrl; 	ctrl = readl_relaxed(event_base + TIMER_ENABLE);	ctrl &= ~(TIMER_ENABLE_EN | TIMER_ENABLE_CLR_ON_MATCH_EN);	writel_relaxed(ctrl, event_base + TIMER_ENABLE);	return 0;} static struct clock_event_device __percpu *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 struct clocksource msm_clocksource = {	.name	= "dg_timer",	.rating	= 300,	.read	= msm_read_timer_count,	.mask	= CLOCKSOURCE_MASK(32),	.flags	= CLOCK_SOURCE_IS_CONTINUOUS,}; static int msm_timer_irq;static int msm_timer_has_ppi; static int msm_local_timer_setup(struct clock_event_device *evt){	int cpu = smp_processor_id();	int err; 	evt->irq = msm_timer_irq;	evt->name = "msm_timer";	evt->features = CLOCK_EVT_FEAT_ONESHOT;	evt->rating = 200;	evt->set_state_shutdown = msm_timer_shutdown;	evt->set_state_oneshot = msm_timer_shutdown;	evt->tick_resume = msm_timer_shutdown;	evt->set_next_event = msm_timer_set_next_event;	evt->cpumask = cpumask_of(cpu); 	clockevents_config_and_register(evt, GPT_HZ, 4, 0xffffffff); 	if (msm_timer_has_ppi) {		enable_percpu_irq(evt->irq, IRQ_TYPE_EDGE_RISING);	} else {		err = request_irq(evt->irq, msm_timer_interrupt,				IRQF_TIMER | IRQF_NOBALANCING |				IRQF_TRIGGER_RISING, "gp_timer", evt);		if (err)			pr_err("request_irq failed\n");	} 	return 0;} static void msm_local_timer_stop(struct clock_event_device *evt){	evt->set_state_shutdown(evt);	disable_percpu_irq(evt->irq);} static int msm_timer_cpu_notify(struct notifier_block *self,					   unsigned long action, void *hcpu){	/*	 * Grab cpu pointer in each case to avoid spurious	 * preemptible warnings	 */	switch (action & ~CPU_TASKS_FROZEN) {	case CPU_STARTING:		msm_local_timer_setup(this_cpu_ptr(msm_evt));		break;	case CPU_DYING:		msm_local_timer_stop(this_cpu_ptr(msm_evt));		break;	} 	return NOTIFY_OK;} static struct notifier_block msm_timer_cpu_nb = {	.notifier_call = msm_timer_cpu_notify,}; static u64 notrace msm_sched_clock_read(void){	return msm_clocksource.read(&msm_clocksource);} static unsigned long msm_read_current_timer(void){	return msm_clocksource.read(&msm_clocksource);} static struct delay_timer msm_delay_timer = {	.read_current_timer = msm_read_current_timer,}; static void __init msm_timer_init(u32 dgt_hz, int sched_bits, int irq,				  bool percpu){	struct clocksource *cs = &msm_clocksource;	int res = 0; 	msm_timer_irq = irq;	msm_timer_has_ppi = percpu; 	msm_evt = alloc_percpu(struct clock_event_device);	if (!msm_evt) {		pr_err("memory allocation failed for clockevents\n");		goto err;	} 	if (percpu)		res = request_percpu_irq(irq, msm_timer_interrupt,					 "gp_timer", msm_evt); 	if (res) {		pr_err("request_percpu_irq failed\n");	} else {		res = register_cpu_notifier(&msm_timer_cpu_nb);		if (res) {			free_percpu_irq(irq, msm_evt);			goto err;		} 		/* Immediately configure the timer on the boot CPU */		msm_local_timer_setup(raw_cpu_ptr(msm_evt));	} 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");	sched_clock_register(msm_sched_clock_read, sched_bits, dgt_hz);	msm_delay_timer.freq = dgt_hz;	register_current_timer_delay(&msm_delay_timer);} static void __init msm_dt_timer_init(struct device_node *np){	u32 freq;	int irq;	struct resource res;	u32 percpu_offset;	void __iomem *base;	void __iomem *cpu0_base; 	base = of_iomap(np, 0);	if (!base) {		pr_err("Failed to map event base\n");		return;	} 	/* We use GPT0 for the clockevent */	irq = irq_of_parse_and_map(np, 1);	if (irq <= 0) {		pr_err("Can't get irq\n");		return;	} 	/* We use CPU0's DGT for the clocksource */	if (of_property_read_u32(np, "cpu-offset", &percpu_offset))		percpu_offset = 0; 	if (of_address_to_resource(np, 0, &res)) {		pr_err("Failed to parse DGT resource\n");		return;	} 	cpu0_base = ioremap(res.start + percpu_offset, resource_size(&res));	if (!cpu0_base) {		pr_err("Failed to map source base\n");		return;	} 	if (of_property_read_u32(np, "clock-frequency", &freq)) {		pr_err("Unknown frequency\n");		return;	} 	event_base = base + 0x4;	sts_base = base + 0x88;	source_base = cpu0_base + 0x24;	freq /= 4;	writel_relaxed(DGT_CLK_CTL_DIV_4, source_base + DGT_CLK_CTL); 	msm_timer_init(freq, 32, irq, !!percpu_offset);}CLOCKSOURCE_OF_DECLARE(kpss_timer, "qcom,kpss-timer", msm_dt_timer_init);CLOCKSOURCE_OF_DECLARE(scss_timer, "qcom,scss-timer", msm_dt_timer_init);