1 /* linux/arch/arm/plat-s3c24xx/s3c24xx-clock.c
3 * Copyright (c) 2004-2005,2008 Simtec Electronics
4 * http://armlinux.simtec.co.uk/
5 * Ben Dooks <ben@simtec.co.uk>
7 * S3C2440/S3C2442 Common clock support
9 * This program is free software; you can redistribute it and/or modify
10 * it under the terms of the GNU General Public License as published by
11 * the Free Software Foundation; either version 2 of the License, or
12 * (at your option) any later version.
14 * This program is distributed in the hope that it will be useful,
15 * but WITHOUT ANY WARRANTY; without even the implied warranty of
16 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
17 * GNU General Public License for more details.
19 * You should have received a copy of the GNU General Public License
20 * along with this program; if not, write to the Free Software
21 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
24 #include <linux/init.h>
25 #include <linux/module.h>
26 #include <linux/kernel.h>
27 #include <linux/list.h>
28 #include <linux/errno.h>
29 #include <linux/err.h>
30 #include <linux/device.h>
31 #include <linux/sysdev.h>
32 #include <linux/interrupt.h>
33 #include <linux/ioport.h>
34 #include <linux/mutex.h>
35 #include <linux/clk.h>
37 #include <mach/hardware.h>
38 #include <asm/atomic.h>
42 #include <mach/regs-clock.h>
44 #include <asm/plat-s3c24xx/clock.h>
45 #include <asm/plat-s3c24xx/cpu.h>
47 static int s3c2440_setparent_armclk(struct clk
*clk
, struct clk
*parent
)
49 unsigned long camdivn
;
54 else if (parent
== &clk_h
)
55 dvs
= S3C2440_CAMDIVN_DVSEN
;
61 camdivn
= __raw_readl(S3C2440_CAMDIVN
);
62 camdivn
&= ~S3C2440_CAMDIVN_DVSEN
;
64 __raw_writel(camdivn
, S3C2440_CAMDIVN
);
69 static struct clk clk_arm
= {
72 .set_parent
= s3c2440_setparent_armclk
,
75 static int s3c244x_clk_add(struct sys_device
*sysdev
)
77 unsigned long camdivn
= __raw_readl(S3C2440_CAMDIVN
);
78 unsigned long clkdivn
;
79 struct clk
*clock_upll
;
82 printk("S3C244X: Clock Support, DVS %s\n",
83 (camdivn
& S3C2440_CAMDIVN_DVSEN
) ? "on" : "off");
85 clk_arm
.parent
= (camdivn
& S3C2440_CAMDIVN_DVSEN
) ? &clk_h
: &clk_f
;
87 ret
= s3c24xx_register_clock(&clk_arm
);
89 printk(KERN_ERR
"S3C24XX: Failed to add armclk (%d)\n", ret
);
93 clock_upll
= clk_get(NULL
, "upll");
94 if (IS_ERR(clock_upll
)) {
95 printk(KERN_ERR
"S3C244X: Failed to get upll clock\n");
99 /* check rate of UPLL, and if it is near 96MHz, then change
100 * to using half the UPLL rate for the system */
102 if (clk_get_rate(clock_upll
) > (94 * MHZ
)) {
103 clk_usb_bus
.rate
= clk_get_rate(clock_upll
) / 2;
105 mutex_lock(&clocks_mutex
);
107 clkdivn
= __raw_readl(S3C2410_CLKDIVN
);
108 clkdivn
|= S3C2440_CLKDIVN_UCLK
;
109 __raw_writel(clkdivn
, S3C2410_CLKDIVN
);
111 mutex_unlock(&clocks_mutex
);
117 static struct sysdev_driver s3c2440_clk_driver
= {
118 .add
= s3c244x_clk_add
,
121 static int s3c2440_clk_init(void)
123 return sysdev_driver_register(&s3c2440_sysclass
, &s3c2440_clk_driver
);
126 arch_initcall(s3c2440_clk_init
);
128 static struct sysdev_driver s3c2442_clk_driver
= {
129 .add
= s3c244x_clk_add
,
132 static int s3c2442_clk_init(void)
134 return sysdev_driver_register(&s3c2442_sysclass
, &s3c2442_clk_driver
);
137 arch_initcall(s3c2442_clk_init
);