diff options
Diffstat (limited to 'arch/arm/mach-s3c24xx/cpufreq-s3c2410.c')
-rw-r--r-- | arch/arm/mach-s3c24xx/cpufreq-s3c2410.c | 160 |
1 files changed, 160 insertions, 0 deletions
diff --git a/arch/arm/mach-s3c24xx/cpufreq-s3c2410.c b/arch/arm/mach-s3c24xx/cpufreq-s3c2410.c new file mode 100644 index 000000000000..cfa0dd8723ec --- /dev/null +++ b/arch/arm/mach-s3c24xx/cpufreq-s3c2410.c | |||
@@ -0,0 +1,160 @@ | |||
1 | /* | ||
2 | * Copyright (c) 2006-2008 Simtec Electronics | ||
3 | * http://armlinux.simtec.co.uk/ | ||
4 | * Ben Dooks <ben@simtec.co.uk> | ||
5 | * | ||
6 | * S3C2410 CPU Frequency scaling | ||
7 | * | ||
8 | * This program is free software; you can redistribute it and/or modify | ||
9 | * it under the terms of the GNU General Public License version 2 as | ||
10 | * published by the Free Software Foundation. | ||
11 | */ | ||
12 | |||
13 | #include <linux/init.h> | ||
14 | #include <linux/module.h> | ||
15 | #include <linux/interrupt.h> | ||
16 | #include <linux/ioport.h> | ||
17 | #include <linux/cpufreq.h> | ||
18 | #include <linux/device.h> | ||
19 | #include <linux/clk.h> | ||
20 | #include <linux/err.h> | ||
21 | #include <linux/io.h> | ||
22 | |||
23 | #include <asm/mach/arch.h> | ||
24 | #include <asm/mach/map.h> | ||
25 | |||
26 | #include <mach/regs-clock.h> | ||
27 | |||
28 | #include <plat/cpu.h> | ||
29 | #include <plat/clock.h> | ||
30 | #include <plat/cpu-freq-core.h> | ||
31 | |||
32 | /* Note, 2410A has an extra mode for 1:4:4 ratio, bit 2 of CLKDIV */ | ||
33 | |||
34 | static void s3c2410_cpufreq_setdivs(struct s3c_cpufreq_config *cfg) | ||
35 | { | ||
36 | u32 clkdiv = 0; | ||
37 | |||
38 | if (cfg->divs.h_divisor == 2) | ||
39 | clkdiv |= S3C2410_CLKDIVN_HDIVN; | ||
40 | |||
41 | if (cfg->divs.p_divisor != cfg->divs.h_divisor) | ||
42 | clkdiv |= S3C2410_CLKDIVN_PDIVN; | ||
43 | |||
44 | __raw_writel(clkdiv, S3C2410_CLKDIVN); | ||
45 | } | ||
46 | |||
47 | static int s3c2410_cpufreq_calcdivs(struct s3c_cpufreq_config *cfg) | ||
48 | { | ||
49 | unsigned long hclk, fclk, pclk; | ||
50 | unsigned int hdiv, pdiv; | ||
51 | unsigned long hclk_max; | ||
52 | |||
53 | fclk = cfg->freq.fclk; | ||
54 | hclk_max = cfg->max.hclk; | ||
55 | |||
56 | cfg->freq.armclk = fclk; | ||
57 | |||
58 | s3c_freq_dbg("%s: fclk is %lu, max hclk %lu\n", | ||
59 | __func__, fclk, hclk_max); | ||
60 | |||
61 | hdiv = (fclk > cfg->max.hclk) ? 2 : 1; | ||
62 | hclk = fclk / hdiv; | ||
63 | |||
64 | if (hclk > cfg->max.hclk) { | ||
65 | s3c_freq_dbg("%s: hclk too big\n", __func__); | ||
66 | return -EINVAL; | ||
67 | } | ||
68 | |||
69 | pdiv = (hclk > cfg->max.pclk) ? 2 : 1; | ||
70 | pclk = hclk / pdiv; | ||
71 | |||
72 | if (pclk > cfg->max.pclk) { | ||
73 | s3c_freq_dbg("%s: pclk too big\n", __func__); | ||
74 | return -EINVAL; | ||
75 | } | ||
76 | |||
77 | pdiv *= hdiv; | ||
78 | |||
79 | /* record the result */ | ||
80 | cfg->divs.p_divisor = pdiv; | ||
81 | cfg->divs.h_divisor = hdiv; | ||
82 | |||
83 | return 0; | ||
84 | } | ||
85 | |||
86 | static struct s3c_cpufreq_info s3c2410_cpufreq_info = { | ||
87 | .max = { | ||
88 | .fclk = 200000000, | ||
89 | .hclk = 100000000, | ||
90 | .pclk = 50000000, | ||
91 | }, | ||
92 | |||
93 | /* transition latency is about 5ms worst-case, so | ||
94 | * set 10ms to be sure */ | ||
95 | .latency = 10000000, | ||
96 | |||
97 | .locktime_m = 150, | ||
98 | .locktime_u = 150, | ||
99 | .locktime_bits = 12, | ||
100 | |||
101 | .need_pll = 1, | ||
102 | |||
103 | .name = "s3c2410", | ||
104 | .calc_iotiming = s3c2410_iotiming_calc, | ||
105 | .set_iotiming = s3c2410_iotiming_set, | ||
106 | .get_iotiming = s3c2410_iotiming_get, | ||
107 | .resume_clocks = s3c2410_setup_clocks, | ||
108 | |||
109 | .set_fvco = s3c2410_set_fvco, | ||
110 | .set_refresh = s3c2410_cpufreq_setrefresh, | ||
111 | .set_divs = s3c2410_cpufreq_setdivs, | ||
112 | .calc_divs = s3c2410_cpufreq_calcdivs, | ||
113 | |||
114 | .debug_io_show = s3c_cpufreq_debugfs_call(s3c2410_iotiming_debugfs), | ||
115 | }; | ||
116 | |||
117 | static int s3c2410_cpufreq_add(struct device *dev, | ||
118 | struct subsys_interface *sif) | ||
119 | { | ||
120 | return s3c_cpufreq_register(&s3c2410_cpufreq_info); | ||
121 | } | ||
122 | |||
123 | static struct subsys_interface s3c2410_cpufreq_interface = { | ||
124 | .name = "s3c2410_cpufreq", | ||
125 | .subsys = &s3c2410_subsys, | ||
126 | .add_dev = s3c2410_cpufreq_add, | ||
127 | }; | ||
128 | |||
129 | static int __init s3c2410_cpufreq_init(void) | ||
130 | { | ||
131 | return subsys_interface_register(&s3c2410_cpufreq_interface); | ||
132 | } | ||
133 | arch_initcall(s3c2410_cpufreq_init); | ||
134 | |||
135 | static int s3c2410a_cpufreq_add(struct device *dev, | ||
136 | struct subsys_interface *sif) | ||
137 | { | ||
138 | /* alter the maximum freq settings for S3C2410A. If a board knows | ||
139 | * it only has a maximum of 200, then it should register its own | ||
140 | * limits. */ | ||
141 | |||
142 | s3c2410_cpufreq_info.max.fclk = 266000000; | ||
143 | s3c2410_cpufreq_info.max.hclk = 133000000; | ||
144 | s3c2410_cpufreq_info.max.pclk = 66500000; | ||
145 | s3c2410_cpufreq_info.name = "s3c2410a"; | ||
146 | |||
147 | return s3c2410_cpufreq_add(dev, sif); | ||
148 | } | ||
149 | |||
150 | static struct subsys_interface s3c2410a_cpufreq_interface = { | ||
151 | .name = "s3c2410a_cpufreq", | ||
152 | .subsys = &s3c2410a_subsys, | ||
153 | .add_dev = s3c2410a_cpufreq_add, | ||
154 | }; | ||
155 | |||
156 | static int __init s3c2410a_cpufreq_init(void) | ||
157 | { | ||
158 | return subsys_interface_register(&s3c2410a_cpufreq_interface); | ||
159 | } | ||
160 | arch_initcall(s3c2410a_cpufreq_init); | ||