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// SPDX-License-Identifier: GPL-2.0-only/* * Rockchip timer support * * Copyright (C) Daniel Lezcano <daniel.lezcano@linaro.org> */#include <linux/clk.h>#include <linux/clockchips.h>#include <linux/init.h>#include <linux/interrupt.h>#include <linux/sched_clock.h>#include <linux/slab.h>#include <linux/of.h>#include <linux/of_address.h>#include <linux/of_irq.h> #define TIMER_NAME "rk_timer" #define TIMER_LOAD_COUNT0	0x00#define TIMER_LOAD_COUNT1	0x04#define TIMER_CURRENT_VALUE0	0x08#define TIMER_CURRENT_VALUE1	0x0C#define TIMER_CONTROL_REG3288	0x10#define TIMER_CONTROL_REG3399	0x1c#define TIMER_INT_STATUS	0x18 #define TIMER_DISABLE		0x0#define TIMER_ENABLE		0x1#define TIMER_MODE_FREE_RUNNING			(0 << 1)#define TIMER_MODE_USER_DEFINED_COUNT		(1 << 1)#define TIMER_INT_UNMASK			(1 << 2) struct rk_timer {	void __iomem *base;	void __iomem *ctrl;	struct clk *clk;	struct clk *pclk;	u32 freq;	int irq;}; struct rk_clkevt {	struct clock_event_device ce;	struct rk_timer timer;}; static struct rk_clkevt *rk_clkevt;static struct rk_timer *rk_clksrc; static inline struct rk_timer *rk_timer(struct clock_event_device *ce){	return &container_of(ce, struct rk_clkevt, ce)->timer;} static inline void rk_timer_disable(struct rk_timer *timer){	writel_relaxed(TIMER_DISABLE, timer->ctrl);} static inline void rk_timer_enable(struct rk_timer *timer, u32 flags){	writel_relaxed(TIMER_ENABLE | flags, timer->ctrl);} static void rk_timer_update_counter(unsigned long cycles,				    struct rk_timer *timer){	writel_relaxed(cycles, timer->base + TIMER_LOAD_COUNT0);	writel_relaxed(0, timer->base + TIMER_LOAD_COUNT1);} static void rk_timer_interrupt_clear(struct rk_timer *timer){	writel_relaxed(1, timer->base + TIMER_INT_STATUS);} static inline int rk_timer_set_next_event(unsigned long cycles,					  struct clock_event_device *ce){	struct rk_timer *timer = rk_timer(ce); 	rk_timer_disable(timer);	rk_timer_update_counter(cycles, timer);	rk_timer_enable(timer, TIMER_MODE_USER_DEFINED_COUNT |			       TIMER_INT_UNMASK);	return 0;} static int rk_timer_shutdown(struct clock_event_device *ce){	struct rk_timer *timer = rk_timer(ce); 	rk_timer_disable(timer);	return 0;} static int rk_timer_set_periodic(struct clock_event_device *ce){	struct rk_timer *timer = rk_timer(ce); 	rk_timer_disable(timer);	rk_timer_update_counter(timer->freq / HZ - 1, timer);	rk_timer_enable(timer, TIMER_MODE_FREE_RUNNING | TIMER_INT_UNMASK);	return 0;} static irqreturn_t rk_timer_interrupt(int irq, void *dev_id){	struct clock_event_device *ce = dev_id;	struct rk_timer *timer = rk_timer(ce); 	rk_timer_interrupt_clear(timer); 	if (clockevent_state_oneshot(ce))		rk_timer_disable(timer); 	ce->event_handler(ce); 	return IRQ_HANDLED;} static u64 notrace rk_timer_sched_read(void){	return ~readl_relaxed(rk_clksrc->base + TIMER_CURRENT_VALUE0);} static int __initrk_timer_probe(struct rk_timer *timer, struct device_node *np){	struct clk *timer_clk;	struct clk *pclk;	int ret = -EINVAL, irq;	u32 ctrl_reg = TIMER_CONTROL_REG3288; 	timer->base = of_iomap(np, 0);	if (!timer->base) {		pr_err("Failed to get base address for '%s'\n", TIMER_NAME);		return -ENXIO;	} 	if (of_device_is_compatible(np, "rockchip,rk3399-timer"))		ctrl_reg = TIMER_CONTROL_REG3399; 	timer->ctrl = timer->base + ctrl_reg; 	pclk = of_clk_get_by_name(np, "pclk");	if (IS_ERR(pclk)) {		ret = PTR_ERR(pclk);		pr_err("Failed to get pclk for '%s'\n", TIMER_NAME);		goto out_unmap;	} 	ret = clk_prepare_enable(pclk);	if (ret) {		pr_err("Failed to enable pclk for '%s'\n", TIMER_NAME);		goto out_unmap;	}	timer->pclk = pclk; 	timer_clk = of_clk_get_by_name(np, "timer");	if (IS_ERR(timer_clk)) {		ret = PTR_ERR(timer_clk);		pr_err("Failed to get timer clock for '%s'\n", TIMER_NAME);		goto out_timer_clk;	} 	ret = clk_prepare_enable(timer_clk);	if (ret) {		pr_err("Failed to enable timer clock\n");		goto out_timer_clk;	}	timer->clk = timer_clk; 	timer->freq = clk_get_rate(timer_clk); 	irq = irq_of_parse_and_map(np, 0);	if (!irq) {		ret = -EINVAL;		pr_err("Failed to map interrupts for '%s'\n", TIMER_NAME);		goto out_irq;	}	timer->irq = irq; 	rk_timer_interrupt_clear(timer);	rk_timer_disable(timer);	return 0; out_irq:	clk_disable_unprepare(timer_clk);out_timer_clk:	clk_disable_unprepare(pclk);out_unmap:	iounmap(timer->base); 	return ret;} static void __init rk_timer_cleanup(struct rk_timer *timer){	clk_disable_unprepare(timer->clk);	clk_disable_unprepare(timer->pclk);	iounmap(timer->base);} static int __init rk_clkevt_init(struct device_node *np){	struct clock_event_device *ce;	int ret = -EINVAL; 	rk_clkevt = kzalloc_obj(struct rk_clkevt);	if (!rk_clkevt) {		ret = -ENOMEM;		goto out;	} 	ret = rk_timer_probe(&rk_clkevt->timer, np);	if (ret)		goto out_probe; 	ce = &rk_clkevt->ce;	ce->name = TIMER_NAME;	ce->features = CLOCK_EVT_FEAT_PERIODIC | CLOCK_EVT_FEAT_ONESHOT |		       CLOCK_EVT_FEAT_DYNIRQ;	ce->set_next_event = rk_timer_set_next_event;	ce->set_state_shutdown = rk_timer_shutdown;	ce->set_state_periodic = rk_timer_set_periodic;	ce->irq = rk_clkevt->timer.irq;	ce->cpumask = cpu_possible_mask;	ce->rating = 250; 	ret = request_irq(rk_clkevt->timer.irq, rk_timer_interrupt, IRQF_TIMER,			  TIMER_NAME, ce);	if (ret) {		pr_err("Failed to initialize '%s': %d\n",			TIMER_NAME, ret);		goto out_irq;	} 	clockevents_config_and_register(&rk_clkevt->ce,					rk_clkevt->timer.freq, 1, UINT_MAX);	return 0; out_irq:	rk_timer_cleanup(&rk_clkevt->timer);out_probe:	kfree(rk_clkevt);out:	/* Leave rk_clkevt not NULL to prevent future init */	rk_clkevt = ERR_PTR(ret);	return ret;} static int __init rk_clksrc_init(struct device_node *np){	int ret = -EINVAL; 	rk_clksrc = kzalloc_obj(struct rk_timer);	if (!rk_clksrc) {		ret = -ENOMEM;		goto out;	} 	ret = rk_timer_probe(rk_clksrc, np);	if (ret)		goto out_probe; 	rk_timer_update_counter(UINT_MAX, rk_clksrc);	rk_timer_enable(rk_clksrc, 0); 	ret = clocksource_mmio_init(rk_clksrc->base + TIMER_CURRENT_VALUE0,		TIMER_NAME, rk_clksrc->freq, 250, 32,		clocksource_mmio_readl_down);	if (ret) {		pr_err("Failed to register clocksource\n");		goto out_clocksource;	} 	sched_clock_register(rk_timer_sched_read, 32, rk_clksrc->freq);	return 0; out_clocksource:	rk_timer_cleanup(rk_clksrc);out_probe:	kfree(rk_clksrc);out:	/* Leave rk_clksrc not NULL to prevent future init */	rk_clksrc = ERR_PTR(ret);	return ret;} static int __init rk_timer_init(struct device_node *np){	if (!rk_clkevt)		return rk_clkevt_init(np); 	if (!rk_clksrc)		return rk_clksrc_init(np); 	pr_err("Too many timer definitions for '%s'\n", TIMER_NAME);	return -EINVAL;} TIMER_OF_DECLARE(rk3288_timer, "rockchip,rk3288-timer", rk_timer_init);TIMER_OF_DECLARE(rk3399_timer, "rockchip,rk3399-timer", rk_timer_init);