drivers/clocksource/timer-sp804.c - linux - Git at Google

 // SPDX-License-Identifier: GPL-2.0-or-later
 /*
  *  linux/drivers/clocksource/timer-sp.c
  *
  *  Copyright (C) 1999 - 2003 ARM Limited
  *  Copyright (C) 2000 Deep Blue Solutions Ltd
  */

 #define pr_fmt(fmt)    KBUILD_MODNAME ": " fmt

 #include <linux/clk.h>
 #include <linux/clocksource.h>
 #include <linux/clockchips.h>
 #include <linux/err.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_clk.h>
 #include <linux/of_irq.h>
 #include <linux/sched_clock.h>

 #include "timer-sp.h"

 /* Hisilicon 64-bit timer(a variant of ARM SP804) */
 #define HISI_TIMER_1_BASE	0x00
 #define HISI_TIMER_2_BASE	0x40
 #define HISI_TIMER_LOAD		0x00
 #define HISI_TIMER_LOAD_H	0x04
 #define HISI_TIMER_VALUE	0x08
 #define HISI_TIMER_VALUE_H	0x0c
 #define HISI_TIMER_CTRL		0x10
 #define HISI_TIMER_INTCLR	0x14
 #define HISI_TIMER_RIS		0x18
 #define HISI_TIMER_MIS		0x1c
 #define HISI_TIMER_BGLOAD	0x20
 #define HISI_TIMER_BGLOAD_H	0x24

 static struct sp804_timer arm_sp804_timer __initdata = {
 	.load		= TIMER_LOAD,
 	.value		= TIMER_VALUE,
 	.ctrl		= TIMER_CTRL,
 	.intclr		= TIMER_INTCLR,
 	.timer_base	= {TIMER_1_BASE, TIMER_2_BASE},
 	.width		= 32,
 };

 static struct sp804_timer hisi_sp804_timer __initdata = {
 	.load		= HISI_TIMER_LOAD,
 	.load_h		= HISI_TIMER_LOAD_H,
 	.value		= HISI_TIMER_VALUE,
 	.value_h	= HISI_TIMER_VALUE_H,
 	.ctrl		= HISI_TIMER_CTRL,
 	.intclr		= HISI_TIMER_INTCLR,
 	.timer_base	= {HISI_TIMER_1_BASE, HISI_TIMER_2_BASE},
 	.width		= 64,
 };

 static struct sp804_clkevt sp804_clkevt[NR_TIMERS];

 static long __init sp804_get_clock_rate(struct clk *clk, const char *name)
 {
 	int err;

 	if (!clk)
 		clk = clk_get_sys("sp804", name);
 	if (IS_ERR(clk)) {
 		pr_err("%s clock not found: %ld\n", name, PTR_ERR(clk));
 		return PTR_ERR(clk);
 	}

 	err = clk_prepare_enable(clk);
 	if (err) {
 		pr_err("clock failed to enable: %d\n", err);
 		clk_put(clk);
 		return err;
 	}

 	return clk_get_rate(clk);
 }

 static struct sp804_clkevt * __init sp804_clkevt_get(void __iomem *base)
 {
 	int i;

 	for (i = 0; i < NR_TIMERS; i++) {
 		if (sp804_clkevt[i].base == base)
 			return &sp804_clkevt[i];
 	}

 	/* It's impossible to reach here */
 	WARN_ON(1);

 	return NULL;
 }

 static struct sp804_clkevt *sched_clkevt;

 static u64 notrace sp804_read(void)
 {
 	return ~readl_relaxed(sched_clkevt->value);
 }

 static int __init sp804_clocksource_and_sched_clock_init(void __iomem *base,
 							 const char *name,
 							 struct clk *clk,
 							 int use_sched_clock)
 {
 	long rate;
 	struct sp804_clkevt *clkevt;

 	rate = sp804_get_clock_rate(clk, name);
 	if (rate < 0)
 		return -EINVAL;

 	clkevt = sp804_clkevt_get(base);

 	writel(0, clkevt->ctrl);
 	writel(0xffffffff, clkevt->load);
 	writel(0xffffffff, clkevt->value);
 	if (clkevt->width == 64) {
 		writel(0xffffffff, clkevt->load_h);
 		writel(0xffffffff, clkevt->value_h);
 	}
 	writel(TIMER_CTRL_32BIT | TIMER_CTRL_ENABLE | TIMER_CTRL_PERIODIC,
 		clkevt->ctrl);

 	clocksource_mmio_init(clkevt->value, name,
 		rate, 200, 32, clocksource_mmio_readl_down);

 	if (use_sched_clock) {
 		sched_clkevt = clkevt;
 		sched_clock_register(sp804_read, 32, rate);
 	}

 	return 0;
 }


 static struct sp804_clkevt *common_clkevt;

 /*
  * IRQ handler for the timer
  */
 static irqreturn_t sp804_timer_interrupt(int irq, void *dev_id)
 {
 	struct clock_event_device *evt = dev_id;

 	/* clear the interrupt */
 	writel(1, common_clkevt->intclr);

 	evt->event_handler(evt);

 	return IRQ_HANDLED;
 }

 static inline void timer_shutdown(struct clock_event_device *evt)
 {
 	writel(0, common_clkevt->ctrl);
 }

 static int sp804_shutdown(struct clock_event_device *evt)
 {
 	timer_shutdown(evt);
 	return 0;
 }

 static int sp804_set_periodic(struct clock_event_device *evt)
 {
 	unsigned long ctrl = TIMER_CTRL_32BIT | TIMER_CTRL_IE |
 			     TIMER_CTRL_PERIODIC | TIMER_CTRL_ENABLE;

 	timer_shutdown(evt);
 	writel(common_clkevt->reload, common_clkevt->load);
 	writel(ctrl, common_clkevt->ctrl);
 	return 0;
 }

 static int sp804_set_next_event(unsigned long next,
 	struct clock_event_device *evt)
 {
 	unsigned long ctrl = TIMER_CTRL_32BIT | TIMER_CTRL_IE |
 			     TIMER_CTRL_ONESHOT | TIMER_CTRL_ENABLE;

 	writel(next, common_clkevt->load);
 	writel(ctrl, common_clkevt->ctrl);

 	return 0;
 }

 static struct clock_event_device sp804_clockevent = {
 	.features		= CLOCK_EVT_FEAT_PERIODIC |
 				  CLOCK_EVT_FEAT_ONESHOT |
 				  CLOCK_EVT_FEAT_DYNIRQ,
 	.set_state_shutdown	= sp804_shutdown,
 	.set_state_periodic	= sp804_set_periodic,
 	.set_state_oneshot	= sp804_shutdown,
 	.tick_resume		= sp804_shutdown,
 	.set_next_event		= sp804_set_next_event,
 	.rating			= 300,
 };

 static int __init sp804_clockevents_init(void __iomem *base, unsigned int irq,
 					 struct clk *clk, const char *name)
 {
 	struct clock_event_device *evt = &sp804_clockevent;
 	long rate;

 	rate = sp804_get_clock_rate(clk, name);
 	if (rate < 0)
 		return -EINVAL;

 	common_clkevt = sp804_clkevt_get(base);
 	common_clkevt->reload = DIV_ROUND_CLOSEST(rate, HZ);
 	evt->name = name;
 	evt->irq = irq;
 	evt->cpumask = cpu_possible_mask;

 	writel(0, common_clkevt->ctrl);

 	if (request_irq(irq, sp804_timer_interrupt, IRQF_TIMER | IRQF_IRQPOLL,
 			"timer", &sp804_clockevent))
 		pr_err("request_irq() failed\n");
 	clockevents_config_and_register(evt, rate, 0xf, 0xffffffff);

 	return 0;
 }

 static void __init sp804_clkevt_init(struct sp804_timer *timer, void __iomem *base)
 {
 	int i;

 	for (i = 0; i < NR_TIMERS; i++) {
 		void __iomem *timer_base;
 		struct sp804_clkevt *clkevt;

 		timer_base = base + timer->timer_base[i];
 		clkevt = &sp804_clkevt[i];
 		clkevt->base	= timer_base;
 		clkevt->load	= timer_base + timer->load;
 		clkevt->load_h	= timer_base + timer->load_h;
 		clkevt->value	= timer_base + timer->value;
 		clkevt->value_h	= timer_base + timer->value_h;
 		clkevt->ctrl	= timer_base + timer->ctrl;
 		clkevt->intclr	= timer_base + timer->intclr;
 		clkevt->width	= timer->width;
 	}
 }

 static int __init sp804_of_init(struct device_node *np, struct sp804_timer *timer)
 {
 	static bool initialized = false;
 	void __iomem *base;
 	void __iomem *timer1_base;
 	void __iomem *timer2_base;
 	int irq, ret = -EINVAL;
 	u32 irq_num = 0;
 	struct clk *clk1, *clk2;
 	const char *name = of_get_property(np, "compatible", NULL);

 	base = of_iomap(np, 0);
 	if (!base)
 		return -ENXIO;

 	timer1_base = base + timer->timer_base[0];
 	timer2_base = base + timer->timer_base[1];

 	/* Ensure timers are disabled */
 	writel(0, timer1_base + timer->ctrl);
 	writel(0, timer2_base + timer->ctrl);

 	if (initialized || !of_device_is_available(np)) {
 		ret = -EINVAL;
 		goto err;
 	}

 	clk1 = of_clk_get(np, 0);
 	if (IS_ERR(clk1))
 		clk1 = NULL;

 	/* Get the 2nd clock if the timer has 3 timer clocks */
 	if (of_clk_get_parent_count(np) == 3) {
 		clk2 = of_clk_get(np, 1);
 		if (IS_ERR(clk2)) {
 			pr_err("%pOFn clock not found: %d\n", np,
 				(int)PTR_ERR(clk2));
 			clk2 = NULL;
 		}
 	} else
 		clk2 = clk1;

 	irq = irq_of_parse_and_map(np, 0);
 	if (irq <= 0)
 		goto err;

 	sp804_clkevt_init(timer, base);

 	of_property_read_u32(np, "arm,sp804-has-irq", &irq_num);
 	if (irq_num == 2) {

 		ret = sp804_clockevents_init(timer2_base, irq, clk2, name);
 		if (ret)
 			goto err;

 		ret = sp804_clocksource_and_sched_clock_init(timer1_base,
 							     name, clk1, 1);
 		if (ret)
 			goto err;
 	} else {

 		ret = sp804_clockevents_init(timer1_base, irq, clk1, name);
 		if (ret)
 			goto err;

 		ret = sp804_clocksource_and_sched_clock_init(timer2_base,
 							     name, clk2, 1);
 		if (ret)
 			goto err;
 	}
 	initialized = true;

 	return 0;
 err:
 	iounmap(base);
 	return ret;
 }

 static int __init arm_sp804_of_init(struct device_node *np)
 {
 	return sp804_of_init(np, &arm_sp804_timer);
 }
 TIMER_OF_DECLARE(sp804, "arm,sp804", arm_sp804_of_init);

 static int __init hisi_sp804_of_init(struct device_node *np)
 {
 	return sp804_of_init(np, &hisi_sp804_timer);
 }
 TIMER_OF_DECLARE(hisi_sp804, "hisilicon,sp804", hisi_sp804_of_init);

 static int __init integrator_cp_of_init(struct device_node *np)
 {
 	static int init_count = 0;
 	void __iomem *base;
 	int irq, ret = -EINVAL;
 	const char *name = of_get_property(np, "compatible", NULL);
 	struct clk *clk;

 	base = of_iomap(np, 0);
 	if (!base) {
 		pr_err("Failed to iomap\n");
 		return -ENXIO;
 	}

 	clk = of_clk_get(np, 0);
 	if (IS_ERR(clk)) {
 		pr_err("Failed to get clock\n");
 		return PTR_ERR(clk);
 	}

 	/* Ensure timer is disabled */
 	writel(0, base + arm_sp804_timer.ctrl);

 	if (init_count == 2 || !of_device_is_available(np))
 		goto err;

 	sp804_clkevt_init(&arm_sp804_timer, base);

 	if (!init_count) {
 		ret = sp804_clocksource_and_sched_clock_init(base,
 							     name, clk, 0);
 		if (ret)
 			goto err;
 	} else {
 		irq = irq_of_parse_and_map(np, 0);
 		if (irq <= 0)
 			goto err;

 		ret = sp804_clockevents_init(base, irq, clk, name);
 		if (ret)
 			goto err;
 	}

 	init_count++;
 	return 0;
 err:
 	iounmap(base);
 	return ret;
 }
 TIMER_OF_DECLARE(intcp, "arm,integrator-cp-timer", integrator_cp_of_init);
	// SPDX-License-Identifier: GPL-2.0-or-later
	/*
	* linux/drivers/clocksource/timer-sp.c
	*
	* Copyright (C) 1999 - 2003 ARM Limited
	* Copyright (C) 2000 Deep Blue Solutions Ltd
	*/

	#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt

	#include <linux/clk.h>
	#include <linux/clocksource.h>
	#include <linux/clockchips.h>
	#include <linux/err.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_clk.h>
	#include <linux/of_irq.h>
	#include <linux/sched_clock.h>

	#include "timer-sp.h"

	/* Hisilicon 64-bit timer(a variant of ARM SP804) */
	#define HISI_TIMER_1_BASE 0x00
	#define HISI_TIMER_2_BASE 0x40
	#define HISI_TIMER_LOAD 0x00
	#define HISI_TIMER_LOAD_H 0x04
	#define HISI_TIMER_VALUE 0x08
	#define HISI_TIMER_VALUE_H 0x0c
	#define HISI_TIMER_CTRL 0x10
	#define HISI_TIMER_INTCLR 0x14
	#define HISI_TIMER_RIS 0x18
	#define HISI_TIMER_MIS 0x1c
	#define HISI_TIMER_BGLOAD 0x20
	#define HISI_TIMER_BGLOAD_H 0x24

	static struct sp804_timer arm_sp804_timer __initdata = {
	.load = TIMER_LOAD,
	.value = TIMER_VALUE,
	.ctrl = TIMER_CTRL,
	.intclr = TIMER_INTCLR,
	.timer_base = {TIMER_1_BASE, TIMER_2_BASE},
	.width = 32,
	};

	static struct sp804_timer hisi_sp804_timer __initdata = {
	.load = HISI_TIMER_LOAD,
	.load_h = HISI_TIMER_LOAD_H,
	.value = HISI_TIMER_VALUE,
	.value_h = HISI_TIMER_VALUE_H,
	.ctrl = HISI_TIMER_CTRL,
	.intclr = HISI_TIMER_INTCLR,
	.timer_base = {HISI_TIMER_1_BASE, HISI_TIMER_2_BASE},
	.width = 64,
	};

	static struct sp804_clkevt sp804_clkevt[NR_TIMERS];

	static long __init sp804_get_clock_rate(struct clk clk, const char name)
	{
	int err;

	if (!clk)
	clk = clk_get_sys("sp804", name);
	if (IS_ERR(clk)) {
	pr_err("%s clock not found: %ld\n", name, PTR_ERR(clk));
	return PTR_ERR(clk);
	}

	err = clk_prepare_enable(clk);
	if (err) {
	pr_err("clock failed to enable: %d\n", err);
	clk_put(clk);
	return err;
	}

	return clk_get_rate(clk);
	}

	static struct sp804_clkevt * __init sp804_clkevt_get(void __iomem *base)
	{
	int i;

	for (i = 0; i < NR_TIMERS; i++) {
	if (sp804_clkevt[i].base == base)
	return &sp804_clkevt[i];
	}

	/* It's impossible to reach here */
	WARN_ON(1);

	return NULL;
	}

	static struct sp804_clkevt *sched_clkevt;

	static u64 notrace sp804_read(void)
	{
	return ~readl_relaxed(sched_clkevt->value);
	}

	static int __init sp804_clocksource_and_sched_clock_init(void __iomem *base,
	const char *name,
	struct clk *clk,
	int use_sched_clock)
	{
	long rate;
	struct sp804_clkevt *clkevt;

	rate = sp804_get_clock_rate(clk, name);
	if (rate < 0)
	return -EINVAL;

	clkevt = sp804_clkevt_get(base);

	writel(0, clkevt->ctrl);
	writel(0xffffffff, clkevt->load);
	writel(0xffffffff, clkevt->value);
	if (clkevt->width == 64) {
	writel(0xffffffff, clkevt->load_h);
	writel(0xffffffff, clkevt->value_h);
	}
	writel(TIMER_CTRL_32BIT \| TIMER_CTRL_ENABLE \| TIMER_CTRL_PERIODIC,
	clkevt->ctrl);

	clocksource_mmio_init(clkevt->value, name,
	rate, 200, 32, clocksource_mmio_readl_down);

	if (use_sched_clock) {
	sched_clkevt = clkevt;
	sched_clock_register(sp804_read, 32, rate);
	}

	return 0;
	}


	static struct sp804_clkevt *common_clkevt;

	/*
	* IRQ handler for the timer
	*/
	static irqreturn_t sp804_timer_interrupt(int irq, void *dev_id)
	{
	struct clock_event_device *evt = dev_id;

	/* clear the interrupt */
	writel(1, common_clkevt->intclr);

	evt->event_handler(evt);

	return IRQ_HANDLED;
	}

	static inline void timer_shutdown(struct clock_event_device *evt)
	{
	writel(0, common_clkevt->ctrl);
	}

	static int sp804_shutdown(struct clock_event_device *evt)
	{
	timer_shutdown(evt);
	return 0;
	}

	static int sp804_set_periodic(struct clock_event_device *evt)
	{
	unsigned long ctrl = TIMER_CTRL_32BIT \| TIMER_CTRL_IE \|
	TIMER_CTRL_PERIODIC \| TIMER_CTRL_ENABLE;

	timer_shutdown(evt);
	writel(common_clkevt->reload, common_clkevt->load);
	writel(ctrl, common_clkevt->ctrl);
	return 0;
	}

	static int sp804_set_next_event(unsigned long next,
	struct clock_event_device *evt)
	{
	unsigned long ctrl = TIMER_CTRL_32BIT \| TIMER_CTRL_IE \|
	TIMER_CTRL_ONESHOT \| TIMER_CTRL_ENABLE;

	writel(next, common_clkevt->load);
	writel(ctrl, common_clkevt->ctrl);

	return 0;
	}

	static struct clock_event_device sp804_clockevent = {
	.features = CLOCK_EVT_FEAT_PERIODIC \|
	CLOCK_EVT_FEAT_ONESHOT \|
	CLOCK_EVT_FEAT_DYNIRQ,
	.set_state_shutdown = sp804_shutdown,
	.set_state_periodic = sp804_set_periodic,
	.set_state_oneshot = sp804_shutdown,
	.tick_resume = sp804_shutdown,
	.set_next_event = sp804_set_next_event,
	.rating = 300,
	};

	static int __init sp804_clockevents_init(void __iomem *base, unsigned int irq,
	struct clk clk, const char name)
	{
	struct clock_event_device *evt = &sp804_clockevent;
	long rate;

	rate = sp804_get_clock_rate(clk, name);
	if (rate < 0)
	return -EINVAL;

	common_clkevt = sp804_clkevt_get(base);
	common_clkevt->reload = DIV_ROUND_CLOSEST(rate, HZ);
	evt->name = name;
	evt->irq = irq;
	evt->cpumask = cpu_possible_mask;

	writel(0, common_clkevt->ctrl);

	if (request_irq(irq, sp804_timer_interrupt, IRQF_TIMER \| IRQF_IRQPOLL,
	"timer", &sp804_clockevent))
	pr_err("request_irq() failed\n");
	clockevents_config_and_register(evt, rate, 0xf, 0xffffffff);

	return 0;
	}

	static void __init sp804_clkevt_init(struct sp804_timer timer, void __iomem base)
	{
	int i;

	for (i = 0; i < NR_TIMERS; i++) {
	void __iomem *timer_base;
	struct sp804_clkevt *clkevt;

	timer_base = base + timer->timer_base[i];
	clkevt = &sp804_clkevt[i];
	clkevt->base = timer_base;
	clkevt->load = timer_base + timer->load;
	clkevt->load_h = timer_base + timer->load_h;
	clkevt->value = timer_base + timer->value;
	clkevt->value_h = timer_base + timer->value_h;
	clkevt->ctrl = timer_base + timer->ctrl;
	clkevt->intclr = timer_base + timer->intclr;
	clkevt->width = timer->width;
	}
	}

	static int __init sp804_of_init(struct device_node np, struct sp804_timer timer)
	{
	static bool initialized = false;
	void __iomem *base;
	void __iomem *timer1_base;
	void __iomem *timer2_base;
	int irq, ret = -EINVAL;
	u32 irq_num = 0;
	struct clk clk1, clk2;
	const char *name = of_get_property(np, "compatible", NULL);

	base = of_iomap(np, 0);
	if (!base)
	return -ENXIO;

	timer1_base = base + timer->timer_base[0];
	timer2_base = base + timer->timer_base[1];

	/* Ensure timers are disabled */
	writel(0, timer1_base + timer->ctrl);
	writel(0, timer2_base + timer->ctrl);

	if (initialized \|\| !of_device_is_available(np)) {
	ret = -EINVAL;
	goto err;
	}

	clk1 = of_clk_get(np, 0);
	if (IS_ERR(clk1))
	clk1 = NULL;

	/* Get the 2nd clock if the timer has 3 timer clocks */
	if (of_clk_get_parent_count(np) == 3) {
	clk2 = of_clk_get(np, 1);
	if (IS_ERR(clk2)) {
	pr_err("%pOFn clock not found: %d\n", np,
	(int)PTR_ERR(clk2));
	clk2 = NULL;
	}
	} else
	clk2 = clk1;

	irq = irq_of_parse_and_map(np, 0);
	if (irq <= 0)
	goto err;

	sp804_clkevt_init(timer, base);

	of_property_read_u32(np, "arm,sp804-has-irq", &irq_num);
	if (irq_num == 2) {

	ret = sp804_clockevents_init(timer2_base, irq, clk2, name);
	if (ret)
	goto err;

	ret = sp804_clocksource_and_sched_clock_init(timer1_base,
	name, clk1, 1);
	if (ret)
	goto err;
	} else {

	ret = sp804_clockevents_init(timer1_base, irq, clk1, name);
	if (ret)
	goto err;

	ret = sp804_clocksource_and_sched_clock_init(timer2_base,
	name, clk2, 1);
	if (ret)
	goto err;
	}
	initialized = true;

	return 0;
	err:
	iounmap(base);
	return ret;
	}

	static int __init arm_sp804_of_init(struct device_node *np)
	{
	return sp804_of_init(np, &arm_sp804_timer);
	}
	TIMER_OF_DECLARE(sp804, "arm,sp804", arm_sp804_of_init);

	static int __init hisi_sp804_of_init(struct device_node *np)
	{
	return sp804_of_init(np, &hisi_sp804_timer);
	}
	TIMER_OF_DECLARE(hisi_sp804, "hisilicon,sp804", hisi_sp804_of_init);

	static int __init integrator_cp_of_init(struct device_node *np)
	{
	static int init_count = 0;
	void __iomem *base;
	int irq, ret = -EINVAL;
	const char *name = of_get_property(np, "compatible", NULL);
	struct clk *clk;

	base = of_iomap(np, 0);
	if (!base) {
	pr_err("Failed to iomap\n");
	return -ENXIO;
	}

	clk = of_clk_get(np, 0);
	if (IS_ERR(clk)) {
	pr_err("Failed to get clock\n");
	return PTR_ERR(clk);
	}

	/* Ensure timer is disabled */
	writel(0, base + arm_sp804_timer.ctrl);

	if (init_count == 2 \|\| !of_device_is_available(np))
	goto err;

	sp804_clkevt_init(&arm_sp804_timer, base);

	if (!init_count) {
	ret = sp804_clocksource_and_sched_clock_init(base,
	name, clk, 0);
	if (ret)
	goto err;
	} else {
	irq = irq_of_parse_and_map(np, 0);
	if (irq <= 0)
	goto err;

	ret = sp804_clockevents_init(base, irq, clk, name);
	if (ret)
	goto err;
	}

	init_count++;
	return 0;
	err:
	iounmap(base);
	return ret;
	}
	TIMER_OF_DECLARE(intcp, "arm,integrator-cp-timer", integrator_cp_of_init);