| /* 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 <mach/hardware.h> |
| #include <asm/irq.h> |
| #include <asm/io.h> |
| |
| #include <mach/regs-clock.h> |
| #include <mach/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; |
| |
| /* We do not default just do a clk->rate = rate as |
| * the clock may have been made this way by choice. |
| */ |
| |
| WARN_ON(clk->set_rate == NULL); |
| |
| if (clk->set_rate == NULL) |
| 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 */ |
| |
| static int clk_default_setrate(struct clk *clk, unsigned long rate) |
| { |
| clk->rate = rate; |
| return 0; |
| } |
| |
| struct clk clk_xtal = { |
| .name = "xtal", |
| .id = -1, |
| .rate = 0, |
| .parent = NULL, |
| .ctrlbit = 0, |
| }; |
| |
| struct clk clk_mpll = { |
| .name = "mpll", |
| .id = -1, |
| .set_rate = clk_default_setrate, |
| }; |
| |
| 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, |
| .set_rate = clk_default_setrate, |
| }; |
| |
| struct clk clk_h = { |
| .name = "hclk", |
| .id = -1, |
| .rate = 0, |
| .parent = NULL, |
| .ctrlbit = 0, |
| .set_rate = clk_default_setrate, |
| }; |
| |
| struct clk clk_p = { |
| .name = "pclk", |
| .id = -1, |
| .rate = 0, |
| .parent = NULL, |
| .ctrlbit = 0, |
| .set_rate = clk_default_setrate, |
| }; |
| |
| 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 unsigned long s3c24xx_calc_div(struct clk *clk, unsigned long rate) |
| { |
| unsigned long div; |
| |
| if ((rate == 0) || !clk->parent) |
| return 0; |
| |
| div = clk_get_rate(clk->parent) / rate; |
| if (div < 2) |
| div = 2; |
| else if (div > 16) |
| div = 16; |
| |
| return div; |
| } |
| |
| static unsigned long s3c24xx_round_dclk_rate(struct clk *clk, |
| unsigned long rate) |
| { |
| unsigned long div = s3c24xx_calc_div(clk, rate); |
| |
| if (div == 0) |
| return 0; |
| |
| return clk_get_rate(clk->parent) / div; |
| } |
| |
| static int s3c24xx_set_dclk_rate(struct clk *clk, unsigned long rate) |
| { |
| unsigned long mask, data, div = s3c24xx_calc_div(clk, rate); |
| |
| if (div == 0) |
| return -EINVAL; |
| |
| if (clk == &s3c24xx_dclk0) { |
| mask = S3C2410_DCLKCON_DCLK0_DIV_MASK | |
| S3C2410_DCLKCON_DCLK0_CMP_MASK; |
| data = S3C2410_DCLKCON_DCLK0_DIV(div) | |
| S3C2410_DCLKCON_DCLK0_CMP((div + 1) / 2); |
| } else if (clk == &s3c24xx_dclk1) { |
| mask = S3C2410_DCLKCON_DCLK1_DIV_MASK | |
| S3C2410_DCLKCON_DCLK1_CMP_MASK; |
| data = S3C2410_DCLKCON_DCLK1_DIV(div) | |
| S3C2410_DCLKCON_DCLK1_CMP((div + 1) / 2); |
| } else |
| return -EINVAL; |
| |
| clk->rate = clk_get_rate(clk->parent) / div; |
| __raw_writel(((__raw_readl(S3C24XX_DCLKCON) & ~mask) | data), |
| S3C24XX_DCLKCON); |
| return clk->rate; |
| } |
| |
| 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_clkout0) |
| 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, |
| .set_rate = s3c24xx_set_dclk_rate, |
| .round_rate = s3c24xx_round_dclk_rate, |
| }; |
| |
| struct clk s3c24xx_dclk1 = { |
| .name = "dclk1", |
| .id = -1, |
| .ctrlbit = S3C2410_DCLKCON_DCLK1EN, |
| .enable = s3c24xx_dclk_enable, |
| .set_parent = s3c24xx_dclk_setparent, |
| .set_rate = s3c24xx_set_dclk_rate, |
| .round_rate = s3c24xx_round_dclk_rate, |
| }; |
| |
| 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; |
| } |
| |
| 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) |
| fails++; |
| } |
| |
| return fails; |
| } |
| |
| /* 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; |
| } |