// SPDX-License-Identifier: GPL-2.0-or-later /* * Actions Semi Owl timer * * Copyright 2012 Actions Semi Inc. * Author: Actions Semi, Inc. * * Copyright (c) 2017 SUSE Linux GmbH * Author: Andreas Färber */ #include <linux/clk.h> #include <linux/clockchips.h> #include <linux/interrupt.h> #include <linux/irq.h> #include <linux/irqreturn.h> #include <linux/sched_clock.h> #include <linux/of.h> #include <linux/of_address.h> #include <linux/of_irq.h> #define OWL_Tx_CTL 0x0 #define OWL_Tx_CMP 0x4 #define OWL_Tx_VAL 0x8 #define OWL_Tx_CTL_PD BIT(0) #define OWL_Tx_CTL_INTEN BIT(1) #define OWL_Tx_CTL_EN BIT(2) static void __iomem *owl_timer_base; static void __iomem *owl_clksrc_base; static void __iomem *owl_clkevt_base; static inline void owl_timer_reset(void __iomem *base) { writel(0, base + OWL_Tx_CTL); writel(0, base + OWL_Tx_VAL); writel(0, base + OWL_Tx_CMP); } static inline void owl_timer_set_enabled(void __iomem *base, bool enabled) { u32 ctl = readl(base + OWL_Tx_CTL); /* PD bit is cleared when set */ ctl &= ~OWL_Tx_CTL_PD; if (enabled) ctl |= OWL_Tx_CTL_EN; else ctl &= ~OWL_Tx_CTL_EN; writel(ctl, base + OWL_Tx_CTL); } static u64 notrace owl_timer_sched_read(void) { return (u64)readl(owl_clksrc_base + OWL_Tx_VAL); } static int owl_timer_set_state_shutdown(struct clock_event_device *evt) { owl_timer_set_enabled(owl_clkevt_base, false); return 0; } static int owl_timer_set_state_oneshot(struct clock_event_device *evt) { owl_timer_reset(owl_clkevt_base); return 0; } static int owl_timer_tick_resume(struct clock_event_device *evt) { return 0; } static int owl_timer_set_next_event(unsigned long evt, struct clock_event_device *ev) { void __iomem *base = owl_clkevt_base; owl_timer_set_enabled(base, false); writel(OWL_Tx_CTL_INTEN, base + OWL_Tx_CTL); writel(0, base + OWL_Tx_VAL); writel(evt, base + OWL_Tx_CMP); owl_timer_set_enabled(base, true); return 0; } static struct clock_event_device owl_clockevent = { .name = "owl_tick", .rating = 200, .features = CLOCK_EVT_FEAT_ONESHOT | CLOCK_EVT_FEAT_DYNIRQ, .set_state_shutdown = owl_timer_set_state_shutdown, .set_state_oneshot = owl_timer_set_state_oneshot, .tick_resume = owl_timer_tick_resume, .set_next_event = owl_timer_set_next_event, }; static irqreturn_t owl_timer1_interrupt(int irq, void *dev_id) { struct clock_event_device *evt = (struct clock_event_device *)dev_id; writel(OWL_Tx_CTL_PD, owl_clkevt_base + OWL_Tx_CTL); evt->event_handler(evt); return IRQ_HANDLED; } static int __init owl_timer_init(struct device_node *node) { struct clk *clk; unsigned long rate; int timer1_irq, ret; owl_timer_base = of_io_request_and_map(node, 0, "owl-timer"); if (IS_ERR(owl_timer_base)) { pr_err("Can't map timer registers\n"); return PTR_ERR(owl_timer_base); } owl_clksrc_base = owl_timer_base + 0x08; owl_clkevt_base = owl_timer_base + 0x14; timer1_irq = of_irq_get_byname(node, "timer1"); if (timer1_irq <= 0) { pr_err("Can't parse timer1 IRQ\n"); return -EINVAL; } clk = of_clk_get(node, 0); if (IS_ERR(clk)) return PTR_ERR(clk); rate = clk_get_rate(clk); owl_timer_reset(owl_clksrc_base); owl_timer_set_enabled(owl_clksrc_base, true); sched_clock_register(owl_timer_sched_read, 32, rate); clocksource_mmio_init(owl_clksrc_base + OWL_Tx_VAL, node->name, rate, 200, 32, clocksource_mmio_readl_up); owl_timer_reset(owl_clkevt_base); ret = request_irq(timer1_irq, owl_timer1_interrupt, IRQF_TIMER, "owl-timer", &owl_clockevent); if (ret) { pr_err("failed to request irq %d\n", timer1_irq); return ret; } owl_clockevent.cpumask = cpumask_of(0); owl_clockevent.irq = timer1_irq; clockevents_config_and_register(&owl_clockevent, rate, 0xf, 0xffffffff); return 0; } TIMER_OF_DECLARE(owl_s500, "actions,s500-timer", owl_timer_init); TIMER_OF_DECLARE(owl_s700, "actions,s700-timer", owl_timer_init); TIMER_OF_DECLARE(owl_s900, "actions,s900-timer", owl_timer_init);