arch/sh/kernel/cpu/sh2/clock-sh7619.c

   1 /*
   2  * arch/sh/kernel/cpu/sh2/clock-sh7619.c
   3  *
   4  * SH7619 support for the clock framework
   5  *
   6  *  Copyright (C) 2006  Yoshinori Sato
   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 <linux/io.h>
  18 #include <asm/clock.h>
  19 #include <asm/freq.h>
  20 #include <asm/processor.h>
  21
  22 static const int pll1rate[] = {1,2};
  23 static const int pfc_divisors[] = {1,2,0,4};
  24 static unsigned int pll2_mult;
  25
  26 static void master_clk_init(struct clk *clk)
  27 {
  28         clk->rate *= pll2_mult * pll1rate[(__raw_readw(FREQCR) >> 8) & 7];
  29 }
  30
  31 static struct clk_ops sh7619_master_clk_ops = {
  32         .init           = master_clk_init,
  33 };
  34
  35 static unsigned long module_clk_recalc(struct clk *clk)
  36 {
  37         int idx = (__raw_readw(FREQCR) & 0x0007);
  38         return clk->parent->rate / pfc_divisors[idx];
  39 }
  40
  41 static struct clk_ops sh7619_module_clk_ops = {
  42         .recalc         = module_clk_recalc,
  43 };
  44
  45 static unsigned long bus_clk_recalc(struct clk *clk)
  46 {
  47         return clk->parent->rate / pll1rate[(__raw_readw(FREQCR) >> 8) & 7];
  48 }
  49
  50 static struct clk_ops sh7619_bus_clk_ops = {
  51         .recalc         = bus_clk_recalc,
  52 };
  53
  54 static struct clk_ops sh7619_cpu_clk_ops = {
  55         .recalc         = followparent_recalc,
  56 };
  57
  58 static struct clk_ops *sh7619_clk_ops[] = {
  59         &sh7619_master_clk_ops,
  60         &sh7619_module_clk_ops,
  61         &sh7619_bus_clk_ops,
  62         &sh7619_cpu_clk_ops,
  63 };
  64
  65 void __init arch_init_clk_ops(struct clk_ops **ops, int idx)
  66 {
  67         if (test_mode_pin(MODE_PIN2 | MODE_PIN0) ||
  68             test_mode_pin(MODE_PIN2 | MODE_PIN1))
  69                 pll2_mult = 2;
  70         else if (test_mode_pin(MODE_PIN0) || test_mode_pin(MODE_PIN1))
  71                 pll2_mult = 4;
  72
  73         BUG_ON(!pll2_mult);
  74
  75         if (idx < ARRAY_SIZE(sh7619_clk_ops))
  76                 *ops = sh7619_clk_ops[idx];
  77 }