projects / linux.git / blame
| Commit | Line | Data |
|---|---|---|
| 98713e40 | 1 | /* |
| ccae941e | 2 | * Copyright (c) 2006-2008 Simtec Electronics |
| a24c091d BD |
3 | * http://armlinux.simtec.co.uk/ |
| 4 | * Ben Dooks <[email protected]> | |
| 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> | |
| 4a858cfc | 18 | #include <linux/device.h> |
| a24c091d BD |
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> | |
| a24c091d BD |
29 | #include <plat/cpu-freq-core.h> |
| 30 | ||
| 31 | /* Note, 2410A has an extra mode for 1:4:4 ratio, bit 2 of CLKDIV */ | |
| 32 | ||
| 33 | static void s3c2410_cpufreq_setdivs(struct s3c_cpufreq_config *cfg) | |
| 34 | { | |
| 35 | u32 clkdiv = 0; | |
| 36 | ||
| 37 | if (cfg->divs.h_divisor == 2) | |
| 38 | clkdiv |= S3C2410_CLKDIVN_HDIVN; | |
| 39 | ||
| 40 | if (cfg->divs.p_divisor != cfg->divs.h_divisor) | |
| 41 | clkdiv |= S3C2410_CLKDIVN_PDIVN; | |
| 42 | ||
| 43 | __raw_writel(clkdiv, S3C2410_CLKDIVN); | |
| 44 | } | |
| 45 | ||
| 46 | static int s3c2410_cpufreq_calcdivs(struct s3c_cpufreq_config *cfg) | |
| 47 | { | |
| 48 | unsigned long hclk, fclk, pclk; | |
| 49 | unsigned int hdiv, pdiv; | |
| 50 | unsigned long hclk_max; | |
| 51 | ||
| 52 | fclk = cfg->freq.fclk; | |
| 53 | hclk_max = cfg->max.hclk; | |
| 54 | ||
| 55 | cfg->freq.armclk = fclk; | |
| 56 | ||
| 57 | s3c_freq_dbg("%s: fclk is %lu, max hclk %lu\n", | |
| 58 | __func__, fclk, hclk_max); | |
| 59 | ||
| 60 | hdiv = (fclk > cfg->max.hclk) ? 2 : 1; | |
| 61 | hclk = fclk / hdiv; | |
| 62 | ||
| 63 | if (hclk > cfg->max.hclk) { | |
| 64 | s3c_freq_dbg("%s: hclk too big\n", __func__); | |
| 65 | return -EINVAL; | |
| 66 | } | |
| 67 | ||
| 68 | pdiv = (hclk > cfg->max.pclk) ? 2 : 1; | |
| 69 | pclk = hclk / pdiv; | |
| 70 | ||
| 71 | if (pclk > cfg->max.pclk) { | |
| 72 | s3c_freq_dbg("%s: pclk too big\n", __func__); | |
| 73 | return -EINVAL; | |
| 74 | } | |
| 75 | ||
| 76 | pdiv *= hdiv; | |
| 77 | ||
| 78 | /* record the result */ | |
| 79 | cfg->divs.p_divisor = pdiv; | |
| 80 | cfg->divs.h_divisor = hdiv; | |
| 81 | ||
| 98713e40 | 82 | return 0; |
| a24c091d BD |
83 | } |
| 84 | ||
| 85 | static struct s3c_cpufreq_info s3c2410_cpufreq_info = { | |
| 86 | .max = { | |
| 87 | .fclk = 200000000, | |
| 88 | .hclk = 100000000, | |
| 89 | .pclk = 50000000, | |
| 90 | }, | |
| 91 | ||
| 92 | /* transition latency is about 5ms worst-case, so | |
| 93 | * set 10ms to be sure */ | |
| 94 | .latency = 10000000, | |
| 95 | ||
| 96 | .locktime_m = 150, | |
| 97 | .locktime_u = 150, | |
| 98 | .locktime_bits = 12, | |
| 99 | ||
| 100 | .need_pll = 1, | |
| 101 | ||
| 102 | .name = "s3c2410", | |
| 103 | .calc_iotiming = s3c2410_iotiming_calc, | |
| 104 | .set_iotiming = s3c2410_iotiming_set, | |
| 105 | .get_iotiming = s3c2410_iotiming_get, | |
| a24c091d BD |
106 | |
| 107 | .set_fvco = s3c2410_set_fvco, | |
| 108 | .set_refresh = s3c2410_cpufreq_setrefresh, | |
| 109 | .set_divs = s3c2410_cpufreq_setdivs, | |
| 110 | .calc_divs = s3c2410_cpufreq_calcdivs, | |
| e6d197a6 BD |
111 | |
| 112 | .debug_io_show = s3c_cpufreq_debugfs_call(s3c2410_iotiming_debugfs), | |
| a24c091d BD |
113 | }; |
| 114 | ||
| 04511a6f HS |
115 | static int s3c2410_cpufreq_add(struct device *dev, |
| 116 | struct subsys_interface *sif) | |
| a24c091d BD |
117 | { |
| 118 | return s3c_cpufreq_register(&s3c2410_cpufreq_info); | |
| 119 | } | |
| 120 | ||
| 4a858cfc KS |
121 | static struct subsys_interface s3c2410_cpufreq_interface = { |
| 122 | .name = "s3c2410_cpufreq", | |
| 123 | .subsys = &s3c2410_subsys, | |
| 124 | .add_dev = s3c2410_cpufreq_add, | |
| a24c091d BD |
125 | }; |
| 126 | ||
| 127 | static int __init s3c2410_cpufreq_init(void) | |
| 128 | { | |
| 4a858cfc | 129 | return subsys_interface_register(&s3c2410_cpufreq_interface); |
| a24c091d | 130 | } |
| a24c091d BD |
131 | arch_initcall(s3c2410_cpufreq_init); |
| 132 | ||
| 04511a6f HS |
133 | static int s3c2410a_cpufreq_add(struct device *dev, |
| 134 | struct subsys_interface *sif) | |
| a24c091d BD |
135 | { |
| 136 | /* alter the maximum freq settings for S3C2410A. If a board knows | |
| 137 | * it only has a maximum of 200, then it should register its own | |
| 138 | * limits. */ | |
| 139 | ||
| 140 | s3c2410_cpufreq_info.max.fclk = 266000000; | |
| 141 | s3c2410_cpufreq_info.max.hclk = 133000000; | |
| 142 | s3c2410_cpufreq_info.max.pclk = 66500000; | |
| 143 | s3c2410_cpufreq_info.name = "s3c2410a"; | |
| 144 | ||
| 04511a6f | 145 | return s3c2410_cpufreq_add(dev, sif); |
| a24c091d BD |
146 | } |
| 147 | ||
| 4a858cfc KS |
148 | static struct subsys_interface s3c2410a_cpufreq_interface = { |
| 149 | .name = "s3c2410a_cpufreq", | |
| 150 | .subsys = &s3c2410a_subsys, | |
| 151 | .add_dev = s3c2410a_cpufreq_add, | |
| a24c091d BD |
152 | }; |
| 153 | ||
| 154 | static int __init s3c2410a_cpufreq_init(void) | |
| 155 | { | |
| 4a858cfc | 156 | return subsys_interface_register(&s3c2410a_cpufreq_interface); |
| a24c091d | 157 | } |
| a24c091d | 158 | arch_initcall(s3c2410a_cpufreq_init); |