arch/sh/kernel/cpu/sh3/clock-sh7712.c

   1 /*
   2  * arch/sh/kernel/cpu/sh3/clock-sh7712.c
   3  *
   4  * SH7712 support for the clock framework
   5  *
   6  *  Copyright (C) 2007  Andrew Murray <amurray@mpc-data.co.uk>
   7  *
   8  * Based on arch/sh/kernel/cpu/sh3/clock-sh3.c
   9  *  Copyright (C) 2005  Paul Mundt
  10  *
  11  * This file is subject to the terms and conditions of the GNU General Public
  12  * License.  See the file "COPYING" in the main directory of this archive
  13  * for more details.
  14  */
  15 #include <linux/init.h>
  16 #include <linux/kernel.h>
  17 #include <asm/clock.h>
  18 #include <asm/freq.h>
  19 #include <asm/io.h>
  20
  21 static int multipliers[] = { 1, 2, 3 };
  22 static int divisors[]    = { 1, 2, 3, 4, 6 };
  23
  24 static void master_clk_init(struct clk *clk)
  25 {
  26         int frqcr = __raw_readw(FRQCR);
  27         int idx = (frqcr & 0x0300) >> 8;
  28
  29         clk->rate *= multipliers[idx];
  30 }
  31
  32 static struct sh_clk_ops sh7712_master_clk_ops = {
  33         .init           = master_clk_init,
  34 };
  35
  36 static unsigned long module_clk_recalc(struct clk *clk)
  37 {
  38         int frqcr = __raw_readw(FRQCR);
  39         int idx = frqcr & 0x0007;
  40
  41         return clk->parent->rate / divisors[idx];
  42 }
  43
  44 static struct sh_clk_ops sh7712_module_clk_ops = {
  45         .recalc         = module_clk_recalc,
  46 };
  47
  48 static unsigned long cpu_clk_recalc(struct clk *clk)
  49 {
  50         int frqcr = __raw_readw(FRQCR);
  51         int idx = (frqcr & 0x0030) >> 4;
  52
  53         return clk->parent->rate / divisors[idx];
  54 }
  55
  56 static struct sh_clk_ops sh7712_cpu_clk_ops = {
  57         .recalc         = cpu_clk_recalc,
  58 };
  59
  60 static struct sh_clk_ops *sh7712_clk_ops[] = {
  61         &sh7712_master_clk_ops,
  62         &sh7712_module_clk_ops,
  63         &sh7712_cpu_clk_ops,
  64 };
  65
  66 void __init arch_init_clk_ops(struct sh_clk_ops **ops, int idx)
  67 {
  68         if (idx < ARRAY_SIZE(sh7712_clk_ops))
  69                 *ops = sh7712_clk_ops[idx];
  70 }
  71