diff options
Diffstat (limited to 'arch/arm/plat-s3c24xx/clock.c')
-rw-r--r-- | arch/arm/plat-s3c24xx/clock.c | 449 |
1 files changed, 449 insertions, 0 deletions
diff --git a/arch/arm/plat-s3c24xx/clock.c b/arch/arm/plat-s3c24xx/clock.c new file mode 100644 index 000000000000..d3dc03a7383a --- /dev/null +++ b/arch/arm/plat-s3c24xx/clock.c @@ -0,0 +1,449 @@ +/* linux/arch/arm/plat-s3c24xx/clock.c + * + * Copyright (c) 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/sysdev.h> +#include <linux/interrupt.h> +#include <linux/ioport.h> +#include <linux/clk.h> +#include <linux/mutex.h> +#include <linux/delay.h> + +#include <asm/hardware.h> +#include <asm/irq.h> +#include <asm/io.h> + +#include <asm/arch/regs-clock.h> +#include <asm/arch/regs-gpio.h> + +#include <asm/plat-s3c24xx/clock.h> +#include <asm/plat-s3c24xx/cpu.h> + +/* clock information */ + +static LIST_HEAD(clocks); + +DEFINE_MUTEX(clocks_mutex); + +/* enable and disable calls for use with the clk struct */ + +static int clk_null_enable(struct clk *clk, int enable) +{ + return 0; +} + +/* Clock API calls */ + +struct clk *clk_get(struct device *dev, const char *id) +{ + struct clk *p; + struct clk *clk = ERR_PTR(-ENOENT); + int idno; + + if (dev == NULL || dev->bus != &platform_bus_type) + idno = -1; + else + idno = to_platform_device(dev)->id; + + mutex_lock(&clocks_mutex); + + list_for_each_entry(p, &clocks, list) { + if (p->id == idno && + strcmp(id, p->name) == 0 && + try_module_get(p->owner)) { + clk = p; + break; + } + } + + /* check for the case where a device was supplied, but the + * clock that was being searched for is not device specific */ + + if (IS_ERR(clk)) { + list_for_each_entry(p, &clocks, list) { + if (p->id == -1 && strcmp(id, p->name) == 0 && + try_module_get(p->owner)) { + clk = p; + break; + } + } + } + + mutex_unlock(&clocks_mutex); + return clk; +} + +void clk_put(struct clk *clk) +{ + module_put(clk->owner); +} + +int clk_enable(struct clk *clk) +{ + if (IS_ERR(clk) || clk == NULL) + return -EINVAL; + + clk_enable(clk->parent); + + mutex_lock(&clocks_mutex); + + if ((clk->usage++) == 0) + (clk->enable)(clk, 1); + + mutex_unlock(&clocks_mutex); + return 0; +} + +void clk_disable(struct clk *clk) +{ + if (IS_ERR(clk) || clk == NULL) + return; + + mutex_lock(&clocks_mutex); + + if ((--clk->usage) == 0) + (clk->enable)(clk, 0); + + mutex_unlock(&clocks_mutex); + clk_disable(clk->parent); +} + + +unsigned long clk_get_rate(struct clk *clk) +{ + if (IS_ERR(clk)) + return 0; + + if (clk->rate != 0) + return clk->rate; + + if (clk->get_rate != NULL) + return (clk->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(clk) && clk->round_rate) + return (clk->round_rate)(clk, rate); + + return rate; +} + +int clk_set_rate(struct clk *clk, unsigned long rate) +{ + int ret; + + if (IS_ERR(clk)) + return -EINVAL; + + mutex_lock(&clocks_mutex); + ret = (clk->set_rate)(clk, rate); + mutex_unlock(&clocks_mutex); + + return ret; +} + +struct clk *clk_get_parent(struct clk *clk) +{ + return clk->parent; +} + +int clk_set_parent(struct clk *clk, struct clk *parent) +{ + int ret = 0; + + if (IS_ERR(clk)) + return -EINVAL; + + mutex_lock(&clocks_mutex); + + if (clk->set_parent) + ret = (clk->set_parent)(clk, parent); + + mutex_unlock(&clocks_mutex); + + return ret; +} + +EXPORT_SYMBOL(clk_get); +EXPORT_SYMBOL(clk_put); +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 */ + +struct clk clk_xtal = { + .name = "xtal", + .id = -1, + .rate = 0, + .parent = NULL, + .ctrlbit = 0, +}; + +struct clk clk_mpll = { + .name = "mpll", + .id = -1, +}; + +struct clk clk_upll = { + .name = "upll", + .id = -1, + .parent = NULL, + .ctrlbit = 0, +}; + +struct clk clk_f = { + .name = "fclk", + .id = -1, + .rate = 0, + .parent = &clk_mpll, + .ctrlbit = 0, +}; + +struct clk clk_h = { + .name = "hclk", + .id = -1, + .rate = 0, + .parent = NULL, + .ctrlbit = 0, +}; + +struct clk clk_p = { + .name = "pclk", + .id = -1, + .rate = 0, + .parent = NULL, + .ctrlbit = 0, +}; + +struct clk clk_usb_bus = { + .name = "usb-bus", + .id = -1, + .rate = 0, + .parent = &clk_upll, +}; + +/* clocks that could be registered by external code */ + +static int s3c24xx_dclk_enable(struct clk *clk, int enable) +{ + unsigned long dclkcon = __raw_readl(S3C24XX_DCLKCON); + + if (enable) + dclkcon |= clk->ctrlbit; + else + dclkcon &= ~clk->ctrlbit; + + __raw_writel(dclkcon, S3C24XX_DCLKCON); + + return 0; +} + +static int s3c24xx_dclk_setparent(struct clk *clk, struct clk *parent) +{ + unsigned long dclkcon; + unsigned int uclk; + + if (parent == &clk_upll) + uclk = 1; + else if (parent == &clk_p) + uclk = 0; + else + return -EINVAL; + + clk->parent = parent; + + dclkcon = __raw_readl(S3C24XX_DCLKCON); + + if (clk->ctrlbit == S3C2410_DCLKCON_DCLK0EN) { + if (uclk) + dclkcon |= S3C2410_DCLKCON_DCLK0_UCLK; + else + dclkcon &= ~S3C2410_DCLKCON_DCLK0_UCLK; + } else { + if (uclk) + dclkcon |= S3C2410_DCLKCON_DCLK1_UCLK; + else + dclkcon &= ~S3C2410_DCLKCON_DCLK1_UCLK; + } + + __raw_writel(dclkcon, S3C24XX_DCLKCON); + + return 0; +} + + +static int s3c24xx_clkout_setparent(struct clk *clk, struct clk *parent) +{ + unsigned long mask; + unsigned long source; + + /* calculate the MISCCR setting for the clock */ + + if (parent == &clk_xtal) + source = S3C2410_MISCCR_CLK0_MPLL; + else if (parent == &clk_upll) + source = S3C2410_MISCCR_CLK0_UPLL; + else if (parent == &clk_f) + source = S3C2410_MISCCR_CLK0_FCLK; + else if (parent == &clk_h) + source = S3C2410_MISCCR_CLK0_HCLK; + else if (parent == &clk_p) + source = S3C2410_MISCCR_CLK0_PCLK; + else if (clk == &s3c24xx_clkout0 && parent == &s3c24xx_dclk0) + source = S3C2410_MISCCR_CLK0_DCLK0; + else if (clk == &s3c24xx_clkout1 && parent == &s3c24xx_dclk1) + source = S3C2410_MISCCR_CLK0_DCLK0; + else + return -EINVAL; + + clk->parent = parent; + + if (clk == &s3c24xx_dclk0) + mask = S3C2410_MISCCR_CLK0_MASK; + else { + source <<= 4; + mask = S3C2410_MISCCR_CLK1_MASK; + } + + s3c2410_modify_misccr(mask, source); + return 0; +} + +/* external clock definitions */ + +struct clk s3c24xx_dclk0 = { + .name = "dclk0", + .id = -1, + .ctrlbit = S3C2410_DCLKCON_DCLK0EN, + .enable = s3c24xx_dclk_enable, + .set_parent = s3c24xx_dclk_setparent, +}; + +struct clk s3c24xx_dclk1 = { + .name = "dclk1", + .id = -1, + .ctrlbit = S3C2410_DCLKCON_DCLK0EN, + .enable = s3c24xx_dclk_enable, + .set_parent = s3c24xx_dclk_setparent, +}; + +struct clk s3c24xx_clkout0 = { + .name = "clkout0", + .id = -1, + .set_parent = s3c24xx_clkout_setparent, +}; + +struct clk s3c24xx_clkout1 = { + .name = "clkout1", + .id = -1, + .set_parent = s3c24xx_clkout_setparent, +}; + +struct clk s3c24xx_uclk = { + .name = "uclk", + .id = -1, +}; + +/* initialise the clock system */ + +int s3c24xx_register_clock(struct clk *clk) +{ + clk->owner = THIS_MODULE; + + if (clk->enable == NULL) + clk->enable = clk_null_enable; + + /* add to the list of available clocks */ + + mutex_lock(&clocks_mutex); + list_add(&clk->list, &clocks); + mutex_unlock(&clocks_mutex); + + return 0; +} + +/* initalise all the clocks */ + +int __init s3c24xx_setup_clocks(unsigned long xtal, + unsigned long fclk, + unsigned long hclk, + unsigned long pclk) +{ + printk(KERN_INFO "S3C24XX Clocks, (c) 2004 Simtec Electronics\n"); + + /* initialise the main system clocks */ + + clk_xtal.rate = xtal; + clk_upll.rate = s3c2410_get_pll(__raw_readl(S3C2410_UPLLCON), xtal); + + clk_mpll.rate = fclk; + clk_h.rate = hclk; + clk_p.rate = pclk; + clk_f.rate = fclk; + + /* assume uart clocks are correctly setup */ + + /* 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; +} |