diff options
Diffstat (limited to 'arch/arm/mach-s3c2440/s3c244x-clock.c')
-rw-r--r-- | arch/arm/mach-s3c2440/s3c244x-clock.c | 138 |
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 | |||
46 | static 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 | |||
68 | static struct clk clk_arm = { | ||
69 | .name = "armclk", | ||
70 | .id = -1, | ||
71 | .ops = &(struct clk_ops) { | ||
72 | .set_parent = s3c2440_setparent_armclk, | ||
73 | }, | ||
74 | }; | ||
75 | |||
76 | static 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 | |||
118 | static struct sysdev_driver s3c2440_clk_driver = { | ||
119 | .add = s3c244x_clk_add, | ||
120 | }; | ||
121 | |||
122 | static int s3c2440_clk_init(void) | ||
123 | { | ||
124 | return sysdev_driver_register(&s3c2440_sysclass, &s3c2440_clk_driver); | ||
125 | } | ||
126 | |||
127 | arch_initcall(s3c2440_clk_init); | ||
128 | |||
129 | static struct sysdev_driver s3c2442_clk_driver = { | ||
130 | .add = s3c244x_clk_add, | ||
131 | }; | ||
132 | |||
133 | static int s3c2442_clk_init(void) | ||
134 | { | ||
135 | return sysdev_driver_register(&s3c2442_sysclass, &s3c2442_clk_driver); | ||
136 | } | ||
137 | |||
138 | arch_initcall(s3c2442_clk_init); | ||