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Diffstat (limited to 'arch/arm/mach-s3c2440/s3c244x-clock.c')
-rw-r--r--arch/arm/mach-s3c2440/s3c244x-clock.c138
1 files changed, 138 insertions, 0 deletions
diff --git a/arch/arm/mach-s3c2440/s3c244x-clock.c b/arch/arm/mach-s3c2440/s3c244x-clock.c
new file mode 100644
index 000000000000..f8d96130d1d1
--- /dev/null
+++ b/arch/arm/mach-s3c2440/s3c244x-clock.c
@@ -0,0 +1,138 @@
1/* linux/arch/arm/plat-s3c24xx/s3c24xx-clock.c
2 *
3 * Copyright (c) 2004-2008 Simtec Electronics
4 * http://armlinux.simtec.co.uk/
5 * Ben Dooks <ben@simtec.co.uk>
6 *
7 * S3C2440/S3C2442 Common clock support
8 *
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.
13 *
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.
18 *
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
22*/
23
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/clk.h>
35#include <linux/io.h>
36
37#include <mach/hardware.h>
38#include <asm/atomic.h>
39#include <asm/irq.h>
40
41#include <mach/regs-clock.h>
42
43#include <plat/clock.h>
44#include <plat/cpu.h>
45
46static int s3c2440_setparent_armclk(struct clk *clk, struct clk *parent)
47{
48 unsigned long camdivn;
49 unsigned long dvs;
50
51 if (parent == &clk_f)
52 dvs = 0;
53 else if (parent == &clk_h)
54 dvs = S3C2440_CAMDIVN_DVSEN;
55 else
56 return -EINVAL;
57
58 clk->parent = parent;
59
60 camdivn = __raw_readl(S3C2440_CAMDIVN);
61 camdivn &= ~S3C2440_CAMDIVN_DVSEN;
62 camdivn |= dvs;
63 __raw_writel(camdivn, S3C2440_CAMDIVN);
64
65 return 0;
66}
67
68static struct clk clk_arm = {
69 .name = "armclk",
70 .id = -1,
71 .ops = &(struct clk_ops) {
72 .set_parent = s3c2440_setparent_armclk,
73 },
74};
75
76static int s3c244x_clk_add(struct sys_device *sysdev)
77{
78 unsigned long camdivn = __raw_readl(S3C2440_CAMDIVN);
79 unsigned long clkdivn;
80 struct clk *clock_upll;
81 int ret;
82
83 printk("S3C244X: Clock Support, DVS %s\n",
84 (camdivn & S3C2440_CAMDIVN_DVSEN) ? "on" : "off");
85
86 clk_arm.parent = (camdivn & S3C2440_CAMDIVN_DVSEN) ? &clk_h : &clk_f;
87
88 ret = s3c24xx_register_clock(&clk_arm);
89 if (ret < 0) {
90 printk(KERN_ERR "S3C24XX: Failed to add armclk (%d)\n", ret);
91 return ret;
92 }
93
94 clock_upll = clk_get(NULL, "upll");
95 if (IS_ERR(clock_upll)) {
96 printk(KERN_ERR "S3C244X: Failed to get upll clock\n");
97 return -ENOENT;
98 }
99
100 /* check rate of UPLL, and if it is near 96MHz, then change
101 * to using half the UPLL rate for the system */
102
103 if (clk_get_rate(clock_upll) > (94 * MHZ)) {
104 clk_usb_bus.rate = clk_get_rate(clock_upll) / 2;
105
106 spin_lock(&clocks_lock);
107
108 clkdivn = __raw_readl(S3C2410_CLKDIVN);
109 clkdivn |= S3C2440_CLKDIVN_UCLK;
110 __raw_writel(clkdivn, S3C2410_CLKDIVN);
111
112 spin_unlock(&clocks_lock);
113 }
114
115 return 0;
116}
117
118static struct sysdev_driver s3c2440_clk_driver = {
119 .add = s3c244x_clk_add,
120};
121
122static int s3c2440_clk_init(void)
123{
124 return sysdev_driver_register(&s3c2440_sysclass, &s3c2440_clk_driver);
125}
126
127arch_initcall(s3c2440_clk_init);
128
129static struct sysdev_driver s3c2442_clk_driver = {
130 .add = s3c244x_clk_add,
131};
132
133static int s3c2442_clk_init(void)
134{
135 return sysdev_driver_register(&s3c2442_sysclass, &s3c2442_clk_driver);
136}
137
138arch_initcall(s3c2442_clk_init);