// SPDX-License-Identifier: GPL-2.0+ /* * RDA8810PL SoC timer driver * * Copyright RDA Microelectronics Company Limited * Copyright (c) 2017 Andreas Färber * Copyright (c) 2018 Manivannan Sadhasivam * * RDA8810PL has two independent timers: OSTIMER (56 bit) and HWTIMER (64 bit). * Each timer provides optional interrupt support. In this driver, OSTIMER is * used for clockevents and HWTIMER is used for clocksource. */ #include <linux/init.h> #include <linux/interrupt.h> #include "timer-of.h" #define RDA_OSTIMER_LOADVAL_L 0x000 #define RDA_OSTIMER_CTRL 0x004 #define RDA_HWTIMER_LOCKVAL_L 0x024 #define RDA_HWTIMER_LOCKVAL_H 0x028 #define RDA_TIMER_IRQ_MASK_SET 0x02c #define RDA_TIMER_IRQ_MASK_CLR 0x030 #define RDA_TIMER_IRQ_CLR 0x034 #define RDA_OSTIMER_CTRL_ENABLE BIT(24) #define RDA_OSTIMER_CTRL_REPEAT BIT(28) #define RDA_OSTIMER_CTRL_LOAD BIT(30) #define RDA_TIMER_IRQ_MASK_OSTIMER BIT(0) #define RDA_TIMER_IRQ_CLR_OSTIMER BIT(0) static int rda_ostimer_start(void __iomem *base, bool periodic, u64 cycles) { u32 ctrl, load_l; load_l = (u32)cycles; ctrl = ((cycles >> 32) & 0xffffff); ctrl |= RDA_OSTIMER_CTRL_LOAD | RDA_OSTIMER_CTRL_ENABLE; if (periodic) ctrl |= RDA_OSTIMER_CTRL_REPEAT; /* Enable ostimer interrupt first */ writel_relaxed(RDA_TIMER_IRQ_MASK_OSTIMER, base + RDA_TIMER_IRQ_MASK_SET); /* Write low 32 bits first, high 24 bits are with ctrl */ writel_relaxed(load_l, base + RDA_OSTIMER_LOADVAL_L); writel_relaxed(ctrl, base + RDA_OSTIMER_CTRL); return 0; } static int rda_ostimer_stop(void __iomem *base) { /* Disable ostimer interrupt first */ writel_relaxed(RDA_TIMER_IRQ_MASK_OSTIMER, base + RDA_TIMER_IRQ_MASK_CLR); writel_relaxed(0, base + RDA_OSTIMER_CTRL); return 0; } static int rda_ostimer_set_state_shutdown(struct clock_event_device *evt) { struct timer_of *to = to_timer_of(evt); rda_ostimer_stop(timer_of_base(to)); return 0; } static int rda_ostimer_set_state_oneshot(struct clock_event_device *evt) { struct timer_of *to = to_timer_of(evt); rda_ostimer_stop(timer_of_base(to)); return 0; } static int rda_ostimer_set_state_periodic(struct clock_event_device *evt) { struct timer_of *to = to_timer_of(evt); unsigned long cycles_per_jiffy; rda_ostimer_stop(timer_of_base(to)); cycles_per_jiffy = ((unsigned long long)NSEC_PER_SEC / HZ * evt->mult) >> evt->shift; rda_ostimer_start(timer_of_base(to), true, cycles_per_jiffy); return 0; } static int rda_ostimer_tick_resume(struct clock_event_device *evt) { return 0; } static int rda_ostimer_set_next_event(unsigned long evt, struct clock_event_device *ev) { struct timer_of *to = to_timer_of(ev); rda_ostimer_start(timer_of_base(to), false, evt); return 0; } static irqreturn_t rda_ostimer_interrupt(int irq, void *dev_id) { struct clock_event_device *evt = dev_id; struct timer_of *to = to_timer_of(evt); /* clear timer int */ writel_relaxed(RDA_TIMER_IRQ_CLR_OSTIMER, timer_of_base(to) + RDA_TIMER_IRQ_CLR); if (evt->event_handler) evt->event_handler(evt); return IRQ_HANDLED; } static struct timer_of rda_ostimer_of = { .flags = TIMER_OF_IRQ | TIMER_OF_BASE, .clkevt = { .name = "rda-ostimer", .rating = 250, .features = CLOCK_EVT_FEAT_PERIODIC | CLOCK_EVT_FEAT_ONESHOT | CLOCK_EVT_FEAT_DYNIRQ, .set_state_shutdown = rda_ostimer_set_state_shutdown, .set_state_oneshot = rda_ostimer_set_state_oneshot, .set_state_periodic = rda_ostimer_set_state_periodic, .tick_resume = rda_ostimer_tick_resume, .set_next_event = rda_ostimer_set_next_event, }, .of_base = { .name = "rda-timer", .index = 0, }, .of_irq = { .name = "ostimer", .handler = rda_ostimer_interrupt, .flags = IRQF_TIMER, }, }; static u64 rda_hwtimer_read(struct clocksource *cs) { void __iomem *base = timer_of_base(&rda_ostimer_of); u32 lo, hi; /* Always read low 32 bits first */ do { lo = readl_relaxed(base + RDA_HWTIMER_LOCKVAL_L); hi = readl_relaxed(base + RDA_HWTIMER_LOCKVAL_H); } while (hi != readl_relaxed(base + RDA_HWTIMER_LOCKVAL_H)); return ((u64)hi << 32) | lo; } static struct clocksource rda_hwtimer_clocksource = { .name = "rda-timer", .rating = 400, .read = rda_hwtimer_read, .mask = CLOCKSOURCE_MASK(64), .flags = CLOCK_SOURCE_IS_CONTINUOUS, }; static int __init rda_timer_init(struct device_node *np) { unsigned long rate = 2000000; int ret; ret = timer_of_init(np, &rda_ostimer_of); if (ret) return ret; clocksource_register_hz(&rda_hwtimer_clocksource, rate); clockevents_config_and_register(&rda_ostimer_of.clkevt, rate, 0x2, UINT_MAX); return 0; } TIMER_OF_DECLARE(rda8810pl, "rda,8810pl-timer", rda_timer_init);