/* linux/arch/arm/plat-s3c24xx/s3c24xx-clock.c
*
* Copyright (c) 2004-2008 Simtec Electronics
* http://armlinux.simtec.co.uk/
* Ben Dooks <ben@simtec.co.uk>
*
* S3C2440/S3C2442 Common clock support
*
* 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/device.h>
#include <linux/interrupt.h>
#include <linux/ioport.h>
#include <linux/clk.h>
#include <linux/io.h>
#include <mach/hardware.h>
#include <linux/atomic.h>
#include <asm/irq.h>
#include <mach/regs-clock.h>
#include <plat/clock.h>
#include <plat/cpu.h>
static int s3c2440_setparent_armclk(struct clk *clk, struct clk *parent)
{
unsigned long camdivn;
unsigned long dvs;
if (parent == &clk_f)
dvs = 0;
else if (parent == &clk_h)
dvs = S3C2440_CAMDIVN_DVSEN;
else
return -EINVAL;
clk->parent = parent;
camdivn = __raw_readl(S3C2440_CAMDIVN);
camdivn &= ~S3C2440_CAMDIVN_DVSEN;
camdivn |= dvs;
__raw_writel(camdivn, S3C2440_CAMDIVN);
return 0;
}
static struct clk clk_arm = {
.name = "armclk",
.id = -1,
.ops = &(struct clk_ops) {
.set_parent = s3c2440_setparent_armclk,
},
};
static int s3c244x_clk_add(struct device *dev, struct subsys_interface *sif)
{
unsigned long camdivn = __raw_readl(S3C2440_CAMDIVN);
unsigned long clkdivn;
struct clk *clock_upll;
int ret;
printk("S3C244X: Clock Support, DVS %s\n",
(camdivn & S3C2440_CAMDIVN_DVSEN) ? "on" : "off");
clk_arm.parent = (camdivn & S3C2440_CAMDIVN_DVSEN) ? &clk_h : &clk_f;
ret = s3c24xx_register_clock(&clk_arm);
if (ret < 0) {
printk(KERN_ERR "S3C24XX: Failed to add armclk (%d)\n", ret);
return ret;
}
clock_upll = clk_get(NULL, "upll");
if (IS_ERR(clock_upll)) {
printk(KERN_ERR "S3C244X: Failed to get upll clock\n");
return -ENOENT;
}
/* check rate of UPLL, and if it is near 96MHz, then change
* to using half the UPLL rate for the system */
if (clk_get_rate(clock_upll) > (94 * MHZ)) {
clk_usb_bus.rate = clk_get_rate(clock_upll) / 2;
spin_lock(&clocks_lock);
clkdivn = __raw_readl(S3C2410_CLKDIVN);
clkdivn |= S3C2440_CLKDIVN_UCLK;
__raw_writel(clkdivn, S3C2410_CLKDIVN);
spin_unlock(&clocks_lock);
}
return 0;
}
static struct subsys_interface s3c2440_clk_interface = {
.name = "s3c2440_clk",
.subsys = &s3c2440_subsys,
.add_dev = s3c244x_clk_add,
};
static int s3c2440_clk_init(void)
{
return subsys_interface_register(&s3c2440_clk_interface);
}
arch_initcall(s3c2440_clk_init);
static struct subsys_interface s3c2442_clk_interface = {
.name = "s3c2442_clk",
.subsys = &s3c2442_subsys,
.add_dev = s3c244x_clk_add,
};
static int s3c2442_clk_init(void)
{
return subsys_interface_register(&s3c2442_clk_interface);
}
arch_initcall(s3c2442_clk_init);
