// SPDX-License-Identifier: GPL-2.0 #include <linux/interrupt.h>#include <linux/ioport.h>#include <linux/clocksource.h>#include <linux/clockchips.h>#include <linux/module.h>#include <linux/slab.h>#include <linux/goldfish.h>#include <clocksource/timer-goldfish.h> struct goldfish_timer {	struct clocksource cs;	struct clock_event_device ced;	struct resource res;	void __iomem *base;}; static struct goldfish_timer *ced_to_gf(struct clock_event_device *ced){	return container_of(ced, struct goldfish_timer, ced);} static struct goldfish_timer *cs_to_gf(struct clocksource *cs){	return container_of(cs, struct goldfish_timer, cs);} static u64 goldfish_timer_read(struct clocksource *cs){	struct goldfish_timer *timerdrv = cs_to_gf(cs);	void __iomem *base = timerdrv->base;	u32 time_low, time_high;	u64 ticks; 	/*	 * time_low: get low bits of current time and update time_high	 * time_high: get high bits of time at last time_low read	 */	time_low = gf_ioread32(base + TIMER_TIME_LOW);	time_high = gf_ioread32(base + TIMER_TIME_HIGH); 	ticks = ((u64)time_high << 32) | time_low; 	return ticks;} static int goldfish_timer_set_oneshot(struct clock_event_device *evt){	struct goldfish_timer *timerdrv = ced_to_gf(evt);	void __iomem *base = timerdrv->base; 	gf_iowrite32(0, base + TIMER_ALARM_HIGH);	gf_iowrite32(0, base + TIMER_ALARM_LOW);	gf_iowrite32(1, base + TIMER_IRQ_ENABLED); 	return 0;} static int goldfish_timer_shutdown(struct clock_event_device *evt){	struct goldfish_timer *timerdrv = ced_to_gf(evt);	void __iomem *base = timerdrv->base; 	gf_iowrite32(0, base + TIMER_IRQ_ENABLED); 	return 0;} static int goldfish_timer_next_event(unsigned long delta,				     struct clock_event_device *evt){	struct goldfish_timer *timerdrv = ced_to_gf(evt);	void __iomem *base = timerdrv->base;	u64 now; 	now = goldfish_timer_read(&timerdrv->cs); 	now += delta; 	gf_iowrite32(upper_32_bits(now), base + TIMER_ALARM_HIGH);	gf_iowrite32(lower_32_bits(now), base + TIMER_ALARM_LOW); 	return 0;} static irqreturn_t goldfish_timer_irq(int irq, void *dev_id){	struct goldfish_timer *timerdrv = dev_id;	struct clock_event_device *evt = &timerdrv->ced;	void __iomem *base = timerdrv->base; 	gf_iowrite32(1, base + TIMER_CLEAR_INTERRUPT); 	evt->event_handler(evt); 	return IRQ_HANDLED;} int __init goldfish_timer_init(int irq, void __iomem *base){	struct goldfish_timer *timerdrv;	int ret; 	timerdrv = kzalloc_obj(*timerdrv);	if (!timerdrv)		return -ENOMEM; 	timerdrv->base = base; 	timerdrv->ced = (struct clock_event_device){		.name			= "goldfish_timer",		.features		= CLOCK_EVT_FEAT_ONESHOT,		.set_state_shutdown	= goldfish_timer_shutdown,		.set_state_oneshot      = goldfish_timer_set_oneshot,		.set_next_event		= goldfish_timer_next_event,	}; 	timerdrv->res = (struct resource){		.name  = "goldfish_timer",		.start = (unsigned long)base,		.end   = (unsigned long)base + 0xfff,	}; 	ret = request_resource(&iomem_resource, &timerdrv->res);	if (ret) {		pr_err("Cannot allocate '%s' resource\n", timerdrv->res.name);		return ret;	} 	timerdrv->cs = (struct clocksource){		.name		= "goldfish_timer",		.rating		= 400,		.read		= goldfish_timer_read,		.mask		= CLOCKSOURCE_MASK(64),		.flags		= 0,		.max_idle_ns	= LONG_MAX,	}; 	clocksource_register_hz(&timerdrv->cs, NSEC_PER_SEC); 	ret = request_irq(irq, goldfish_timer_irq, IRQF_TIMER,			  "goldfish_timer", timerdrv);	if (ret) {		pr_err("Couldn't register goldfish-timer interrupt\n");		return ret;	} 	clockevents_config_and_register(&timerdrv->ced, NSEC_PER_SEC,					1, 0xffffffff); 	return 0;}