drivers/clocksource/timer-u300.c

1 // SPDX-License-Identifier: GPL-2.0-only
3  * Copyright (C) 2007-2009 ST-Ericsson AB
35 /* Reset OS Timer 32bit (-/W) */
38 /* Enable OS Timer 32bit (-/W) */
41 /* Disable OS Timer 32bit (-/W) */
44 /* OS Timer Mode Register 32bit (-/W) */
48 /* OS Timer Status Register 32bit (R/-) */
59 /* OS Timer Current Count Register 32bit (R/-) */
61 /* OS Timer Terminal Count Register 32bit (R/W) */
63 /* OS Timer Interrupt Enable Register 32bit (-/W) */
67 /* OS Timer Interrupt Acknowledge Register 32bit (-/W) */
71 /* Reset DD Timer 32bit (-/W) */
74 /* Enable DD Timer 32bit (-/W) */
77 /* Disable DD Timer 32bit (-/W) */
80 /* DD Timer Mode Register 32bit (-/W) */
84 /* DD Timer Status Register 32bit (R/-) */
95 /* DD Timer Current Count Register 32bit (R/-) */
97 /* DD Timer Terminal Count Register 32bit (R/W) */
99 /* DD Timer Interrupt Enable Register 32bit (-/W) */
103 /* DD Timer Interrupt Acknowledge Register 32bit (-/W) */
107 /* Reset GP1 Timer 32bit (-/W) */
110 /* Enable GP1 Timer 32bit (-/W) */
113 /* Disable GP1 Timer 32bit (-/W) */
116 /* GP1 Timer Mode Register 32bit (-/W) */
120 /* GP1 Timer Status Register 32bit (R/-) */
131 /* GP1 Timer Current Count Register 32bit (R/-) */
133 /* GP1 Timer Terminal Count Register 32bit (R/W) */
135 /* GP1 Timer Interrupt Enable Register 32bit (-/W) */
139 /* GP1 Timer Interrupt Acknowledge Register 32bit (-/W) */
143 /* Reset GP2 Timer 32bit (-/W) */
146 /* Enable GP2 Timer 32bit (-/W) */
149 /* Disable GP2 Timer 32bit (-/W) */
152 /* GP2 Timer Mode Register 32bit (-/W) */
156 /* GP2 Timer Status Register 32bit (R/-) */
167 /* GP2 Timer Current Count Register 32bit (R/-) */
169 /* GP2 Timer Terminal Count Register 32bit (R/W) */
171 /* GP2 Timer Interrupt Enable Register 32bit (-/W) */
175 /* GP2 Timer Interrupt Acknowledge Register 32bit (-/W) */
179 /* Clock request control register - all four timers */
192 	/* Disable interrupts on GP1 */  in u300_shutdown()
195 	/* Disable GP1 */  in u300_shutdown()
210 	 * so we just set a dummy value somewhere at the end of the  in u300_set_oneshot()
213 	/* Disable interrupts on GPT1 */  in u300_set_oneshot()
216 	/* Disable GP1 while we're reprogramming it. */  in u300_set_oneshot()
241 	/* Disable interrupts on GPT1 */  in u300_set_periodic()
244 	/* Disable GP1 while we're reprogramming it. */  in u300_set_periodic()
248 	 * Set the periodic mode to a certain number of ticks per  in u300_set_periodic()
251 	writel(cevdata->ticks_per_jiffy,  in u300_set_periodic()
254 	 * Set continuous mode, so the timer keeps triggering  in u300_set_periodic()
269  * The app timer in one shot mode obviously has to be reprogrammed
270  * in EXACTLY this sequence to work properly. Do NOT try to e.g. replace
271  * the interrupt disable + timer disable commands with a reset command,
273  * the timer is very sensitive to the instruction order, though you don't
280 	/* Disable interrupts on GPT1 */  in u300_set_next_event()
283 	/* Disable GP1 while we're reprogramming it. */  in u300_set_next_event()
292 	 * We run one shot per tick here! (This is necessary to reconfigure,  in u300_set_next_event()
329 	evt->event_handler(evt);  in u300_timer_interrupt()
335  * local implementation which uses the clocksource to get some
366 		return -ENXIO;  in u300_timer_init_of()
373 		return -EINVAL;  in u300_timer_init_of()
398 	 * Disable the "OS" and "DD" timers - these are designed for Symbian!  in u300_timer_init_of()
416 	/* Set up the IRQ handler */  in u300_timer_init_of()
425 	/* Set this timer to run around forever */  in u300_timer_init_of()
427 	/* Set continuous mode so it wraps around */  in u300_timer_init_of()
430 	/* Disable timer interrupts */  in u300_timer_init_of()
433 	/* Then enable the GP2 timer to use as a free running us counter */  in u300_timer_init_of()
441 		pr_err("timer: failed to initialize U300 clock source\n");  in u300_timer_init_of()
456 TIMER_OF_DECLARE(u300_timer, "stericsson,u300-apptimer",