| 123456789101112131415161718192021222324252627282930313233343536373839404142434445464748495051525354555657585960616263646566676869707172737475767778798081828384858687888990919293949596979899100101102103104105106107108109110111112113114115116117118119120121122123124125126127128129130131132133134135136137138139140141142143144145146147148149150151152153154155156157158159160161162163164165166167168169170171172173174175176177178179180181182183184185186187188189190191192193194195196197198199200201202203204205206207208209210211212213214215216217218219220221222223224225226227228229230231232233234235236237238239240241242243244245246247248249250251252253254255256257258259260261262263264265266267268269270271272273274275276277278279280281282283284285286287288289290291292293294295296297298299300301302303304305306307308309310311312313314315316317318319320321322323324325326327328329330331332333334335336337338339340341342343344345346347348349350351352353354355356357358359360361362363364365366367368369370371372373374375376377378379380381382383384385386387388389390391392393394395396397398399400401402403404405406407408409410411412413414415416417418419420421422423424425426427428429430431432433434435436437438439440441442443444445446447448449450451452453454455456457 | /* linux/arch/arm/plat-s3c24xx/clock.c * * Copyright 2004-2005 Simtec Electronics *	Ben Dooks <ben@simtec.co.uk> * * S3C24XX Core clock control support * * Based on, and code from linux/arch/arm/mach-versatile/clock.c ** **  Copyright (C) 2004 ARM Limited. **  Written by Deep Blue Solutions Limited. * * * This program is free software; you can redistribute it and/or modify * it under the terms of the GNU General Public License as published by * the Free Software Foundation; either version 2 of the License, or * (at your option) any later version. * * This program is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the * GNU General Public License for more details. * * You should have received a copy of the GNU General Public License * along with this program; if not, write to the Free Software * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA*/#include <linux/init.h>#include <linux/module.h>#include <linux/kernel.h>#include <linux/list.h>#include <linux/errno.h>#include <linux/err.h>#include <linux/platform_device.h>#include <linux/device.h>#include <linux/interrupt.h>#include <linux/ioport.h>#include <linux/clk.h>#include <linux/spinlock.h>#include <linux/io.h>#if defined(CONFIG_DEBUG_FS)#include <linux/debugfs.h>#endif#include <mach/hardware.h>#include <asm/irq.h>#include <plat/cpu-freq.h>#include <plat/clock.h>#include <plat/cpu.h>#include <linux/serial_core.h>#include <plat/regs-serial.h> /* for s3c24xx_uart_devs *//* clock information */static LIST_HEAD(clocks);/* We originally used an mutex here, but some contexts (see resume) * are calling functions such as clk_set_parent() with IRQs disabled * causing an BUG to be triggered. */DEFINE_SPINLOCK(clocks_lock);/* Global watchdog clock used by arch_wtd_reset() callback */struct clk *s3c2410_wdtclk;static int __init s3c_wdt_reset_init(void){	s3c2410_wdtclk = clk_get(NULL, "watchdog");	if (IS_ERR(s3c2410_wdtclk))		printk(KERN_WARNING "%s: warning: cannot get watchdog clock\n", __func__);	return 0;}arch_initcall(s3c_wdt_reset_init);/* enable and disable calls for use with the clk struct */static int clk_null_enable(struct clk *clk, int enable){	return 0;}int clk_enable(struct clk *clk){	unsigned long flags;	if (IS_ERR(clk) || clk == NULL)		return -EINVAL;	clk_enable(clk->parent);	spin_lock_irqsave(&clocks_lock, flags);	if ((clk->usage++) == 0)		(clk->enable)(clk, 1);	spin_unlock_irqrestore(&clocks_lock, flags);	return 0;}void clk_disable(struct clk *clk){	unsigned long flags;	if (IS_ERR(clk) || clk == NULL)		return;	spin_lock_irqsave(&clocks_lock, flags);	if ((--clk->usage) == 0)		(clk->enable)(clk, 0);	spin_unlock_irqrestore(&clocks_lock, flags);	clk_disable(clk->parent);}unsigned long clk_get_rate(struct clk *clk){	if (IS_ERR_OR_NULL(clk))		return 0;	if (clk->rate != 0)		return clk->rate;	if (clk->ops != NULL && clk->ops->get_rate != NULL)		return (clk->ops->get_rate)(clk);	if (clk->parent != NULL)		return clk_get_rate(clk->parent);	return clk->rate;}long clk_round_rate(struct clk *clk, unsigned long rate){	if (!IS_ERR_OR_NULL(clk) && clk->ops && clk->ops->round_rate)		return (clk->ops->round_rate)(clk, rate);	return rate;}int clk_set_rate(struct clk *clk, unsigned long rate){	unsigned long flags;	int ret;	if (IS_ERR_OR_NULL(clk))		return -EINVAL;	/* We do not default just do a clk->rate = rate as	 * the clock may have been made this way by choice.	 */	WARN_ON(clk->ops == NULL);	WARN_ON(clk->ops && clk->ops->set_rate == NULL);	if (clk->ops == NULL || clk->ops->set_rate == NULL)		return -EINVAL;	spin_lock_irqsave(&clocks_lock, flags);	ret = (clk->ops->set_rate)(clk, rate);	spin_unlock_irqrestore(&clocks_lock, flags);	return ret;}struct clk *clk_get_parent(struct clk *clk){	return clk->parent;}int clk_set_parent(struct clk *clk, struct clk *parent){	unsigned long flags;	int ret = 0;	if (IS_ERR_OR_NULL(clk) || IS_ERR_OR_NULL(parent))		return -EINVAL;	spin_lock_irqsave(&clocks_lock, flags);	if (clk->ops && clk->ops->set_parent)		ret = (clk->ops->set_parent)(clk, parent);	spin_unlock_irqrestore(&clocks_lock, flags);	return ret;}EXPORT_SYMBOL(clk_enable);EXPORT_SYMBOL(clk_disable);EXPORT_SYMBOL(clk_get_rate);EXPORT_SYMBOL(clk_round_rate);EXPORT_SYMBOL(clk_set_rate);EXPORT_SYMBOL(clk_get_parent);EXPORT_SYMBOL(clk_set_parent);/* base clocks */int clk_default_setrate(struct clk *clk, unsigned long rate){	clk->rate = rate;	return 0;}struct clk_ops clk_ops_def_setrate = {	.set_rate	= clk_default_setrate,};struct clk clk_xtal = {	.name		= "xtal",	.rate		= 0,	.parent		= NULL,	.ctrlbit	= 0,};struct clk clk_ext = {	.name		= "ext",};struct clk clk_epll = {	.name		= "epll",};struct clk clk_mpll = {	.name		= "mpll",	.ops		= &clk_ops_def_setrate,};struct clk clk_upll = {	.name		= "upll",	.parent		= NULL,	.ctrlbit	= 0,};struct clk clk_f = {	.name		= "fclk",	.rate		= 0,	.parent		= &clk_mpll,	.ctrlbit	= 0,};struct clk clk_h = {	.name		= "hclk",	.rate		= 0,	.parent		= NULL,	.ctrlbit	= 0,	.ops		= &clk_ops_def_setrate,};struct clk clk_p = {	.name		= "pclk",	.rate		= 0,	.parent		= NULL,	.ctrlbit	= 0,	.ops		= &clk_ops_def_setrate,};struct clk clk_usb_bus = {	.name		= "usb-bus",	.rate		= 0,	.parent		= &clk_upll,};struct clk s3c24xx_uclk = {	.name		= "uclk",};/* initialise the clock system *//** * s3c24xx_register_clock() - register a clock * @clk: The clock to register * * Add the specified clock to the list of clocks known by the system. */int s3c24xx_register_clock(struct clk *clk){	if (clk->enable == NULL)		clk->enable = clk_null_enable;	/* fill up the clk_lookup structure and register it*/	clk->lookup.dev_id = clk->devname;	clk->lookup.con_id = clk->name;	clk->lookup.clk = clk;	clkdev_add(&clk->lookup);	return 0;}/** * s3c24xx_register_clocks() - register an array of clock pointers * @clks: Pointer to an array of struct clk pointers * @nr_clks: The number of clocks in the @clks array. * * Call s3c24xx_register_clock() for all the clock pointers contained * in the @clks list. Returns the number of failures. */int s3c24xx_register_clocks(struct clk **clks, int nr_clks){	int fails = 0;	for (; nr_clks > 0; nr_clks--, clks++) {		if (s3c24xx_register_clock(*clks) < 0) {			struct clk *clk = *clks;			printk(KERN_ERR "%s: failed to register %p: %s\n",			       __func__, clk, clk->name);			fails++;		}	}	return fails;}/** * s3c_register_clocks() - register an array of clocks * @clkp: Pointer to the first clock in the array. * @nr_clks: Number of clocks to register. * * Call s3c24xx_register_clock() on the @clkp array given, printing an * error if it fails to register the clock (unlikely). */void __init s3c_register_clocks(struct clk *clkp, int nr_clks){	int ret;	for (; nr_clks > 0; nr_clks--, clkp++) {		ret = s3c24xx_register_clock(clkp);		if (ret < 0) {			printk(KERN_ERR "Failed to register clock %s (%d)\n",			       clkp->name, ret);		}	}}/** * s3c_disable_clocks() - disable an array of clocks * @clkp: Pointer to the first clock in the array. * @nr_clks: Number of clocks to register. * * for internal use only at initialisation time. disable the clocks in the * @clkp array. */void __init s3c_disable_clocks(struct clk *clkp, int nr_clks){	for (; nr_clks > 0; nr_clks--, clkp++)		(clkp->enable)(clkp, 0);}/* initialise all the clocks */int __init s3c24xx_register_baseclocks(unsigned long xtal){	printk(KERN_INFO "S3C24XX Clocks, Copyright 2004 Simtec Electronics\n");	clk_xtal.rate = xtal;	/* register our clocks */	if (s3c24xx_register_clock(&clk_xtal) < 0)		printk(KERN_ERR "failed to register master xtal\n");	if (s3c24xx_register_clock(&clk_mpll) < 0)		printk(KERN_ERR "failed to register mpll clock\n");	if (s3c24xx_register_clock(&clk_upll) < 0)		printk(KERN_ERR "failed to register upll clock\n");	if (s3c24xx_register_clock(&clk_f) < 0)		printk(KERN_ERR "failed to register cpu fclk\n");	if (s3c24xx_register_clock(&clk_h) < 0)		printk(KERN_ERR "failed to register cpu hclk\n");	if (s3c24xx_register_clock(&clk_p) < 0)		printk(KERN_ERR "failed to register cpu pclk\n");	return 0;}#if defined(CONFIG_PM_DEBUG) && defined(CONFIG_DEBUG_FS)/* debugfs support to trace clock tree hierarchy and attributes */static struct dentry *clk_debugfs_root;static void clock_tree_show_one(struct seq_file *s, struct clk *c, int level){	struct clk *child;	const char *state;	char buf[255] = { 0 };	int n = 0;	if (c->name)		n = snprintf(buf, sizeof(buf) - 1, "%s", c->name);	if (c->devname)		n += snprintf(buf + n, sizeof(buf) - 1 - n, ":%s", c->devname);	state = (c->usage > 0) ? "on" : "off";	seq_printf(s, "%*s%-*s %-6s %-3d %-10lu\n",		   level * 3 + 1, "",		   50 - level * 3, buf,		   state, c->usage, clk_get_rate(c));	list_for_each_entry(child, &clocks, list) {		if (child->parent != c)			continue;		clock_tree_show_one(s, child, level + 1);	}}static int clock_tree_show(struct seq_file *s, void *data){	struct clk *c;	unsigned long flags;	seq_printf(s, " clock state ref rate\n");	seq_printf(s, "----------------------------------------------------\n");	spin_lock_irqsave(&clocks_lock, flags);	list_for_each_entry(c, &clocks, list)		if (c->parent == NULL)			clock_tree_show_one(s, c, 0);	spin_unlock_irqrestore(&clocks_lock, flags);	return 0;}static int clock_tree_open(struct inode *inode, struct file *file){	return single_open(file, clock_tree_show, inode->i_private);}static const struct file_operations clock_tree_fops = {	.open		= clock_tree_open,	.read		= seq_read,	.llseek		= seq_lseek,	.release	= single_release,};static int clock_rate_show(void *data, u64 *val){	struct clk *c = data;	*val = clk_get_rate(c);	return 0;}DEFINE_SIMPLE_ATTRIBUTE(clock_rate_fops, clock_rate_show, NULL, "%llu\n");
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