mirror of
				https://github.com/torvalds/linux.git
				synced 2025-10-31 16:48:26 +02:00 
			
		
		
		
	 702107ed5d
			
		
	
	
		702107ed5d
		
	
	
	
	
		
			
			Change "/**" to a common "/*" comment in a non-kernel-doc comment to avoid a kernel-doc warning: timer-ti-32k.c:42: warning: expecting prototype for timer(). Prototype was for OMAP2_32KSYNCNT_REV_OFF() instead Signed-off-by: Randy Dunlap <rdunlap@infradead.org> Cc: Daniel Lezcano <daniel.lezcano@linaro.org> Cc: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org> Link: https://lore.kernel.org/r/20240120173624.16769-1-rdunlap@infradead.org
		
			
				
	
	
		
			165 lines
		
	
	
	
		
			4.2 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
			
		
		
	
	
			165 lines
		
	
	
	
		
			4.2 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
| // SPDX-License-Identifier: GPL-2.0-only
 | |
| /*
 | |
|  * timer-ti-32k.c - OMAP2 32k Timer Support
 | |
|  *
 | |
|  * Copyright (C) 2009 Nokia Corporation
 | |
|  *
 | |
|  * Update to use new clocksource/clockevent layers
 | |
|  * Author: Kevin Hilman, MontaVista Software, Inc. <source@mvista.com>
 | |
|  * Copyright (C) 2007 MontaVista Software, Inc.
 | |
|  *
 | |
|  * Original driver:
 | |
|  * Copyright (C) 2005 Nokia Corporation
 | |
|  * Author: Paul Mundt <paul.mundt@nokia.com>
 | |
|  *         Juha Yrjölä <juha.yrjola@nokia.com>
 | |
|  * OMAP Dual-mode timer framework support by Timo Teras
 | |
|  *
 | |
|  * Some parts based off of TI's 24xx code:
 | |
|  *
 | |
|  * Copyright (C) 2004-2009 Texas Instruments, Inc.
 | |
|  *
 | |
|  * Roughly modelled after the OMAP1 MPU timer code.
 | |
|  * Added OMAP4 support - Santosh Shilimkar <santosh.shilimkar@ti.com>
 | |
|  *
 | |
|  * Copyright (C) 2015 Texas Instruments Incorporated - https://www.ti.com
 | |
|  */
 | |
| 
 | |
| #include <linux/clk.h>
 | |
| #include <linux/init.h>
 | |
| #include <linux/time.h>
 | |
| #include <linux/sched_clock.h>
 | |
| #include <linux/clocksource.h>
 | |
| #include <linux/of.h>
 | |
| #include <linux/of_address.h>
 | |
| 
 | |
| /*
 | |
|  * 32KHz clocksource ... always available, on pretty most chips except
 | |
|  * OMAP 730 and 1510.  Other timers could be used as clocksources, with
 | |
|  * higher resolution in free-running counter modes (e.g. 12 MHz xtal),
 | |
|  * but systems won't necessarily want to spend resources that way.
 | |
|  */
 | |
| 
 | |
| #define OMAP2_32KSYNCNT_REV_OFF		0x0
 | |
| #define OMAP2_32KSYNCNT_REV_SCHEME	(0x3 << 30)
 | |
| #define OMAP2_32KSYNCNT_CR_OFF_LOW	0x10
 | |
| #define OMAP2_32KSYNCNT_CR_OFF_HIGH	0x30
 | |
| 
 | |
| struct ti_32k {
 | |
| 	void __iomem		*base;
 | |
| 	void __iomem		*counter;
 | |
| 	struct clocksource	cs;
 | |
| };
 | |
| 
 | |
| static inline struct ti_32k *to_ti_32k(struct clocksource *cs)
 | |
| {
 | |
| 	return container_of(cs, struct ti_32k, cs);
 | |
| }
 | |
| 
 | |
| static u64 notrace ti_32k_read_cycles(struct clocksource *cs)
 | |
| {
 | |
| 	struct ti_32k *ti = to_ti_32k(cs);
 | |
| 
 | |
| 	return (u64)readl_relaxed(ti->counter);
 | |
| }
 | |
| 
 | |
| static struct ti_32k ti_32k_timer = {
 | |
| 	.cs = {
 | |
| 		.name		= "32k_counter",
 | |
| 		.rating		= 250,
 | |
| 		.read		= ti_32k_read_cycles,
 | |
| 		.mask		= CLOCKSOURCE_MASK(32),
 | |
| 		.flags		= CLOCK_SOURCE_IS_CONTINUOUS,
 | |
| 	},
 | |
| };
 | |
| 
 | |
| static u64 notrace omap_32k_read_sched_clock(void)
 | |
| {
 | |
| 	return ti_32k_read_cycles(&ti_32k_timer.cs);
 | |
| }
 | |
| 
 | |
| static void __init ti_32k_timer_enable_clock(struct device_node *np,
 | |
| 					     const char *name)
 | |
| {
 | |
| 	struct clk *clock;
 | |
| 	int error;
 | |
| 
 | |
| 	clock = of_clk_get_by_name(np->parent, name);
 | |
| 	if (IS_ERR(clock)) {
 | |
| 		/* Only some SoCs have a separate interface clock */
 | |
| 		if (PTR_ERR(clock) == -EINVAL && !strncmp("ick", name, 3))
 | |
| 			return;
 | |
| 
 | |
| 		pr_warn("%s: could not get clock %s %li\n",
 | |
| 			__func__, name, PTR_ERR(clock));
 | |
| 		return;
 | |
| 	}
 | |
| 
 | |
| 	error = clk_prepare_enable(clock);
 | |
| 	if (error) {
 | |
| 		pr_warn("%s: could not enable %s: %i\n",
 | |
| 			__func__, name, error);
 | |
| 		return;
 | |
| 	}
 | |
| }
 | |
| 
 | |
| static void __init ti_32k_timer_module_init(struct device_node *np,
 | |
| 					    void __iomem *base)
 | |
| {
 | |
| 	void __iomem *sysc = base + 4;
 | |
| 
 | |
| 	if (!of_device_is_compatible(np->parent, "ti,sysc"))
 | |
| 		return;
 | |
| 
 | |
| 	ti_32k_timer_enable_clock(np, "fck");
 | |
| 	ti_32k_timer_enable_clock(np, "ick");
 | |
| 
 | |
| 	/*
 | |
| 	 * Force idle module as wkup domain is active with MPU.
 | |
| 	 * No need to tag the module disabled for ti-sysc probe.
 | |
| 	 */
 | |
| 	writel_relaxed(0, sysc);
 | |
| }
 | |
| 
 | |
| static int __init ti_32k_timer_init(struct device_node *np)
 | |
| {
 | |
| 	int ret;
 | |
| 
 | |
| 	ti_32k_timer.base = of_iomap(np, 0);
 | |
| 	if (!ti_32k_timer.base) {
 | |
| 		pr_err("Can't ioremap 32k timer base\n");
 | |
| 		return -ENXIO;
 | |
| 	}
 | |
| 
 | |
| 	if (!of_machine_is_compatible("ti,am43"))
 | |
| 		ti_32k_timer.cs.flags |= CLOCK_SOURCE_SUSPEND_NONSTOP;
 | |
| 
 | |
| 	ti_32k_timer.counter = ti_32k_timer.base;
 | |
| 	ti_32k_timer_module_init(np, ti_32k_timer.base);
 | |
| 
 | |
| 	/*
 | |
| 	 * 32k sync Counter IP register offsets vary between the highlander
 | |
| 	 * version and the legacy ones.
 | |
| 	 *
 | |
| 	 * The 'SCHEME' bits(30-31) of the revision register is used to identify
 | |
| 	 * the version.
 | |
| 	 */
 | |
| 	if (readl_relaxed(ti_32k_timer.base + OMAP2_32KSYNCNT_REV_OFF) &
 | |
| 			OMAP2_32KSYNCNT_REV_SCHEME)
 | |
| 		ti_32k_timer.counter += OMAP2_32KSYNCNT_CR_OFF_HIGH;
 | |
| 	else
 | |
| 		ti_32k_timer.counter += OMAP2_32KSYNCNT_CR_OFF_LOW;
 | |
| 
 | |
| 	pr_info("OMAP clocksource: 32k_counter at 32768 Hz\n");
 | |
| 
 | |
| 	ret = clocksource_register_hz(&ti_32k_timer.cs, 32768);
 | |
| 	if (ret) {
 | |
| 		pr_err("32k_counter: can't register clocksource\n");
 | |
| 		return ret;
 | |
| 	}
 | |
| 
 | |
| 	sched_clock_register(omap_32k_read_sched_clock, 32, 32768);
 | |
| 
 | |
| 	return 0;
 | |
| }
 | |
| TIMER_OF_DECLARE(ti_32k_timer, "ti,omap-counter32k",
 | |
| 		ti_32k_timer_init);
 |