arch/arm/mach-lh7a40x/clocks.c

   1 /* arch/arm/mach-lh7a40x/clocks.c
   2  *
   3  *  Copyright (C) 2004 Marc Singer
   4  *
   5  *  This program is free software; you can redistribute it and/or
   6  *  modify it under the terms of the GNU General Public License
   7  *  version 2 as published by the Free Software Foundation.
   8  *
   9  */
  10
  11 #include <linux/config.h>
  12 #include <linux/cpufreq.h>
  13 #include <asm/hardware.h>
  14 #include <asm/arch/clocks.h>
  15 #include <linux/err.h>
  16
  17 struct module;
  18 struct icst525_params;
  19
  20 struct clk {
  21         struct list_head node;
  22         unsigned long rate;
  23         struct module *owner;
  24         const char *name;
  25 //      void *data;
  26 //      const struct icst525_params *params;
  27 //      void (*setvco)(struct clk *, struct icst525_vco vco);
  28 };
  29
  30 int clk_register(struct clk *clk);
  31 void clk_unregister(struct clk *clk);
  32
  33 /* ----- */
  34
  35 #define MAINDIV1(c)     (((c) >>  7) & 0x0f)
  36 #define MAINDIV2(c)     (((c) >> 11) & 0x1f)
  37 #define PS(c)           (((c) >> 18) & 0x03)
  38 #define PREDIV(c)       (((c) >>  2) & 0x1f)
  39 #define HCLKDIV(c)      (((c) >>  0) & 0x02)
  40 #define PCLKDIV(c)      (((c) >> 16) & 0x03)
  41
  42 unsigned int cpufreq_get (unsigned int cpu) /* in kHz */
  43 {
  44         return fclkfreq_get ()/1000;
  45 }
  46 EXPORT_SYMBOL(cpufreq_get);
  47
  48 unsigned int fclkfreq_get (void)
  49 {
  50         unsigned int clkset = CSC_CLKSET;
  51         unsigned int gclk
  52                 = XTAL_IN
  53                 / (1 << PS(clkset))
  54                 * (MAINDIV1(clkset) + 2)
  55                 / (PREDIV(clkset)   + 2)
  56                 * (MAINDIV2(clkset) + 2)
  57                 ;
  58         return gclk;
  59 }
  60
  61 unsigned int hclkfreq_get (void)
  62 {
  63         unsigned int clkset = CSC_CLKSET;
  64         unsigned int hclk = fclkfreq_get () / (HCLKDIV(clkset) + 1);
  65
  66         return hclk;
  67 }
  68
  69 unsigned int pclkfreq_get (void)
  70 {
  71         unsigned int clkset = CSC_CLKSET;
  72         int pclkdiv = PCLKDIV(clkset);
  73         unsigned int pclk;
  74         if (pclkdiv == 0x3)
  75                 pclkdiv = 0x2;
  76         pclk = hclkfreq_get () / (1 << pclkdiv);
  77
  78         return pclk;
  79 }
  80
  81 /* ----- */
  82
  83 static LIST_HEAD(clocks);
  84 static DECLARE_MUTEX(clocks_sem);
  85
  86 struct clk *clk_get (struct device *dev, const char *id)
  87 {
  88         struct clk *p;
  89         struct clk *clk = ERR_PTR(-ENOENT);
  90
  91         down (&clocks_sem);
  92         list_for_each_entry (p, &clocks, node) {
  93                 if (strcmp (id, p->name) == 0
  94                     && try_module_get(p->owner)) {
  95                         clk = p;
  96                         break;
  97                 }
  98         }
  99         up (&clocks_sem);
 100
 101         return clk;
 102 }
 103 EXPORT_SYMBOL(clk_get);
 104
 105 void clk_put (struct clk *clk)
 106 {
 107         module_put(clk->owner);
 108 }
 109 EXPORT_SYMBOL(clk_put);
 110
 111 int clk_enable (struct clk *clk)
 112 {
 113         return 0;
 114 }
 115 EXPORT_SYMBOL(clk_enable);
 116
 117 void clk_disable (struct clk *clk)
 118 {
 119 }
 120 EXPORT_SYMBOL(clk_disable);
 121
 122 int clk_use (struct clk *clk)
 123 {
 124         return 0;
 125 }
 126 EXPORT_SYMBOL(clk_use);
 127
 128 void clk_unuse (struct clk *clk)
 129 {
 130 }
 131 EXPORT_SYMBOL(clk_unuse);
 132
 133 unsigned long clk_get_rate (struct clk *clk)
 134 {
 135         return clk->rate;
 136 }
 137 EXPORT_SYMBOL(clk_get_rate);
 138
 139 long clk_round_rate (struct clk *clk, unsigned long rate)
 140 {
 141         return rate;
 142 }
 143 EXPORT_SYMBOL(clk_round_rate);
 144
 145 int clk_set_rate (struct clk *clk, unsigned long rate)
 146 {
 147         int ret = -EIO;
 148         return ret;
 149 }
 150 EXPORT_SYMBOL(clk_set_rate);
 151
 152 #if 0
 153 /*
 154  * These are fixed clocks.
 155  */
 156 static struct clk kmi_clk = {
 157         .name   = "KMIREFCLK",
 158         .rate   = 24000000,
 159 };
 160
 161 static struct clk uart_clk = {
 162         .name   = "UARTCLK",
 163         .rate   = 24000000,
 164 };
 165
 166 static struct clk mmci_clk = {
 167         .name   = "MCLK",
 168         .rate   = 33000000,
 169 };
 170 #endif
 171
 172 static struct clk clcd_clk = {
 173         .name   = "CLCDCLK",
 174         .rate   = 0,
 175 };
 176
 177 int clk_register (struct clk *clk)
 178 {
 179         down (&clocks_sem);
 180         list_add (&clk->node, &clocks);
 181         up (&clocks_sem);
 182         return 0;
 183 }
 184 EXPORT_SYMBOL(clk_register);
 185
 186 void clk_unregister (struct clk *clk)
 187 {
 188         down (&clocks_sem);
 189         list_del (&clk->node);
 190         up (&clocks_sem);
 191 }
 192 EXPORT_SYMBOL(clk_unregister);
 193
 194 static int __init clk_init (void)
 195 {
 196         clk_register(&clcd_clk);
 197         return 0;
 198 }
 199 arch_initcall(clk_init);