Linux Kernel  3.7.1
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clock-sh7709.c
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1 /*
2  * arch/sh/kernel/cpu/sh3/clock-sh7709.c
3  *
4  * SH7709 support for the clock framework
5  *
6  * Copyright (C) 2005 Andriy Skulysh
7  *
8  * Based on arch/sh/kernel/cpu/sh3/clock-sh7705.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 stc_multipliers[] = { 1, 2, 4, 8, 3, 6, 1, 1 };
22 static int ifc_divisors[] = { 1, 2, 4, 1, 3, 1, 1, 1 };
23 static int pfc_divisors[] = { 1, 2, 4, 1, 3, 6, 1, 1 };
24 
25 static void master_clk_init(struct clk *clk)
26 {
27  int frqcr = __raw_readw(FRQCR);
28  int idx = ((frqcr & 0x2000) >> 11) | (frqcr & 0x0003);
29 
30  clk->rate *= pfc_divisors[idx];
31 }
32 
33 static struct sh_clk_ops sh7709_master_clk_ops = {
34  .init = master_clk_init,
35 };
36 
37 static unsigned long module_clk_recalc(struct clk *clk)
38 {
39  int frqcr = __raw_readw(FRQCR);
40  int idx = ((frqcr & 0x2000) >> 11) | (frqcr & 0x0003);
41 
42  return clk->parent->rate / pfc_divisors[idx];
43 }
44 
45 static struct sh_clk_ops sh7709_module_clk_ops = {
46  .recalc = module_clk_recalc,
47 };
48 
49 static unsigned long bus_clk_recalc(struct clk *clk)
50 {
51  int frqcr = __raw_readw(FRQCR);
52  int idx = (frqcr & 0x0080) ?
53  ((frqcr & 0x8000) >> 13) | ((frqcr & 0x0030) >> 4) : 1;
54 
55  return clk->parent->rate * stc_multipliers[idx];
56 }
57 
58 static struct sh_clk_ops sh7709_bus_clk_ops = {
59  .recalc = bus_clk_recalc,
60 };
61 
62 static unsigned long cpu_clk_recalc(struct clk *clk)
63 {
64  int frqcr = __raw_readw(FRQCR);
65  int idx = ((frqcr & 0x4000) >> 12) | ((frqcr & 0x000c) >> 2);
66 
67  return clk->parent->rate / ifc_divisors[idx];
68 }
69 
70 static struct sh_clk_ops sh7709_cpu_clk_ops = {
71  .recalc = cpu_clk_recalc,
72 };
73 
74 static struct sh_clk_ops *sh7709_clk_ops[] = {
75  &sh7709_master_clk_ops,
76  &sh7709_module_clk_ops,
77  &sh7709_bus_clk_ops,
78  &sh7709_cpu_clk_ops,
79 };
80 
81 void __init arch_init_clk_ops(struct sh_clk_ops **ops, int idx)
82 {
83  if (idx < ARRAY_SIZE(sh7709_clk_ops))
84  *ops = sh7709_clk_ops[idx];
85 }