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