1 // SPDX-License-Identifier: GPL-2.0
3  * IXP4 timer driver
6  * Based on arch/arm/mach-ixp4xx/common.c
8  * Copyright 2003-2004 (C) MontaVista, Software, Inc.
24  * Constants to make it easy to access Timer Control/Status registers
27 #define IXP4XX_OST1_OFFSET	0x04  /* Timer 1 Timestamp */
28 #define IXP4XX_OSRT1_OFFSET	0x08  /* Timer 1 Reload */
29 #define IXP4XX_OST2_OFFSET	0x0C  /* Timer 2 Timestamp */
30 #define IXP4XX_OSRT2_OFFSET	0x10  /* Timer 2 Reload */
31 #define IXP4XX_OSST_OFFSET	0x20  /* Timer Status */
34  * Timer register values and bit definitions
56  * A local singleton used by sched_clock and delay timer reads, which are
69 	return __raw_readl(local_ixp4xx_timer->base + IXP4XX_OSTS_OFFSET);  in ixp4xx_read_timer()
85 	struct clock_event_device *evt = &tmr->clkevt;  in ixp4xx_timer_interrupt()
89 		     tmr->base + IXP4XX_OSST_OFFSET);  in ixp4xx_timer_interrupt()
91 	evt->event_handler(evt);  in ixp4xx_timer_interrupt()
102 	val = __raw_readl(tmr->base + IXP4XX_OSRT1_OFFSET);  in ixp4xx_set_next_event()
106 		     tmr->base + IXP4XX_OSRT1_OFFSET);  in ixp4xx_set_next_event()
116 	val = __raw_readl(tmr->base + IXP4XX_OSRT1_OFFSET);  in ixp4xx_shutdown()
118 	__raw_writel(val, tmr->base + IXP4XX_OSRT1_OFFSET);  in ixp4xx_shutdown()
128 		     tmr->base + IXP4XX_OSRT1_OFFSET);  in ixp4xx_set_oneshot()
138 	val = tmr->latch & ~IXP4XX_OST_RELOAD_MASK;  in ixp4xx_set_periodic()
140 	__raw_writel(val, tmr->base + IXP4XX_OSRT1_OFFSET);  in ixp4xx_set_periodic()
150 	val = __raw_readl(tmr->base + IXP4XX_OSRT1_OFFSET);  in ixp4xx_resume()
152 	__raw_writel(val, tmr->base + IXP4XX_OSRT1_OFFSET);  in ixp4xx_resume()
158  * IXP4xx timer tick
159  * We use OS timer1 on the CPU for the timer tick and the timestamp
171 		return -ENOMEM;  in ixp4xx_timer_register()
172 	tmr->base = base;  in ixp4xx_timer_register()
175 	 * The timer register doesn't allow to specify the two least  in ixp4xx_timer_register()
180 	tmr->latch = DIV_ROUND_CLOSEST(timer_freq,  in ixp4xx_timer_register()
187 	__raw_writel(0, tmr->base + IXP4XX_OSRT1_OFFSET);  in ixp4xx_timer_register()
189 	/* Clear any pending interrupt on timer 1 */  in ixp4xx_timer_register()
191 		     tmr->base + IXP4XX_OSST_OFFSET);  in ixp4xx_timer_register()
193 	/* Reset time-stamp counter */  in ixp4xx_timer_register()
194 	__raw_writel(0, tmr->base + IXP4XX_OSTS_OFFSET);  in ixp4xx_timer_register()
199 	tmr->clkevt.name = "ixp4xx timer1";  in ixp4xx_timer_register()
200 	tmr->clkevt.features = CLOCK_EVT_FEAT_PERIODIC | CLOCK_EVT_FEAT_ONESHOT;  in ixp4xx_timer_register()
201 	tmr->clkevt.rating = 200;  in ixp4xx_timer_register()
202 	tmr->clkevt.set_state_shutdown = ixp4xx_shutdown;  in ixp4xx_timer_register()
203 	tmr->clkevt.set_state_periodic = ixp4xx_set_periodic;  in ixp4xx_timer_register()
204 	tmr->clkevt.set_state_oneshot = ixp4xx_set_oneshot;  in ixp4xx_timer_register()
205 	tmr->clkevt.tick_resume = ixp4xx_resume;  in ixp4xx_timer_register()
206 	tmr->clkevt.set_next_event = ixp4xx_set_next_event;  in ixp4xx_timer_register()
207 	tmr->clkevt.cpumask = cpumask_of(0);  in ixp4xx_timer_register()
208 	tmr->clkevt.irq = timer_irq;  in ixp4xx_timer_register()
210 			  IRQF_TIMER, "IXP4XX-TIMER1", tmr);  in ixp4xx_timer_register()
212 		pr_crit("no timer IRQ\n");  in ixp4xx_timer_register()
213 		return -ENODEV;  in ixp4xx_timer_register()
215 	clockevents_config_and_register(&tmr->clkevt, timer_freq,  in ixp4xx_timer_register()
221 	/* Also use this timer for delays */  in ixp4xx_timer_register()
222 	tmr->delay_timer.read_current_timer = ixp4xx_read_timer;  in ixp4xx_timer_register()
223 	tmr->delay_timer.freq = timer_freq;  in ixp4xx_timer_register()
224 	register_current_timer_delay(&tmr->delay_timer);  in ixp4xx_timer_register()
231 	.name = "ixp4xx-watchdog",
232 	.id = -1,
236  * This probe gets called after the timer is already up and running. The main
241 	struct device *dev = &pdev->dev;  in ixp4xx_timer_probe()
244 	ixp4xx_watchdog_device.dev.platform_data = local_ixp4xx_timer->base;  in ixp4xx_timer_probe()
250 	{ .compatible = "intel,ixp4xx-timer", },
257 		.name = "ixp4xx-timer",
272 		pr_crit("IXP4xx: can't remap timer\n");  in ixp4xx_of_timer_init()
273 		return -ENODEV;  in ixp4xx_of_timer_init()
279 		ret = -EINVAL;  in ixp4xx_of_timer_init()
293 TIMER_OF_DECLARE(ixp4xx, "intel,ixp4xx-timer", ixp4xx_of_timer_init);