arch/sh/kernel/cpu/sh2a/clock-sh7201.c

   1 /*
   2  * arch/sh/kernel/cpu/sh2a/clock-sh7201.c
   3  *
   4  * SH7201 support for the clock framework
   5  *
   6  *  Copyright (C) 2008 Peter Griffin  <pgriffin@mpc-data.co.uk>
   7  *
   8  * Based on clock-sh4.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 const int pll1rate[]={1,2,3,4,6,8};
  22 static const int pfc_divisors[]={1,2,3,4,6,8,12};
  23 #define ifc_divisors pfc_divisors
  24
  25 #if (CONFIG_SH_CLK_MD == 0)
  26 #define PLL2 (4)
  27 #elif (CONFIG_SH_CLK_MD == 2)
  28 #define PLL2 (2)
  29 #elif (CONFIG_SH_CLK_MD == 3)
  30 #define PLL2 (1)
  31 #else
  32 #error "Illegal Clock Mode!"
  33 #endif
  34
  35 static void master_clk_init(struct clk *clk)
  36 {
  37         return 10000000 * PLL2 * pll1rate[(ctrl_inw(FREQCR) >> 8) & 0x0007];
  38 }
  39
  40 static struct clk_ops sh7201_master_clk_ops = {
  41         .init           = master_clk_init,
  42 };
  43
  44 static unsigned long module_clk_recalc(struct clk *clk)
  45 {
  46         int idx = (ctrl_inw(FREQCR) & 0x0007);
  47         return clk->parent->rate / pfc_divisors[idx];
  48 }
  49
  50 static struct clk_ops sh7201_module_clk_ops = {
  51         .recalc         = module_clk_recalc,
  52 };
  53
  54 static unsigned long bus_clk_recalc(struct clk *clk)
  55 {
  56         int idx = (ctrl_inw(FREQCR) & 0x0007);
  57         return clk->parent->rate / pfc_divisors[idx];
  58 }
  59
  60 static struct clk_ops sh7201_bus_clk_ops = {
  61         .recalc         = bus_clk_recalc,
  62 };
  63
  64 static unsigned long cpu_clk_recalc(struct clk *clk)
  65 {
  66         int idx = ((ctrl_inw(FREQCR) >> 4) & 0x0007);
  67         return clk->parent->rate / ifc_divisors[idx];
  68 }
  69
  70 static struct clk_ops sh7201_cpu_clk_ops = {
  71         .recalc         = cpu_clk_recalc,
  72 };
  73
  74 static struct clk_ops *sh7201_clk_ops[] = {
  75         &sh7201_master_clk_ops,
  76         &sh7201_module_clk_ops,
  77         &sh7201_bus_clk_ops,
  78         &sh7201_cpu_clk_ops,
  79 };
  80
  81 void __init arch_init_clk_ops(struct clk_ops **ops, int idx)
  82 {
  83         if (idx < ARRAY_SIZE(sh7201_clk_ops))
  84                 *ops = sh7201_clk_ops[idx];
  85 }