1 /*
2 * arch/sh/kernel/cpu/sh4/clock-sh4.c
3 *
4 * Generic SH-4 support for the clock framework
5 *
6 * Copyright (C) 2005 Paul Mundt
7 *
8 * FRQCR parsing hacked out of arch/sh/kernel/time.c
9 *
10 * Copyright (C) 1999 Tetsuya Okada & Niibe Yutaka
11 * Copyright (C) 2000 Philipp Rumpf <prumpf@tux.org>
12 * Copyright (C) 2002, 2003, 2004 Paul Mundt
13 * Copyright (C) 2002 M. R. Brown <mrbrown@linux-sh.org>
14 *
15 * This file is subject to the terms and conditions of the GNU General Public
16 * License. See the file "COPYING" in the main directory of this archive
17 * for more details.
18 */
19 #include <linux/init.h>
20 #include <linux/kernel.h>
21 #include <asm/clock.h>
22 #include <asm/freq.h>
23 #include <asm/io.h>
24
25 static int ifc_divisors[] = { 1, 2, 3, 4, 6, 8, 1, 1 };
26 #define bfc_divisors ifc_divisors /* Same */
27 static int pfc_divisors[] = { 2, 3, 4, 6, 8, 2, 2, 2 };
28
master_clk_init(struct clk * clk)29 static void master_clk_init(struct clk *clk)
30 {
31 clk->rate *= pfc_divisors[__raw_readw(FRQCR) & 0x0007];
32 }
33
34 static struct clk_ops sh4_master_clk_ops = {
35 .init = master_clk_init,
36 };
37
module_clk_recalc(struct clk * clk)38 static unsigned long module_clk_recalc(struct clk *clk)
39 {
40 int idx = (__raw_readw(FRQCR) & 0x0007);
41 return clk->parent->rate / pfc_divisors[idx];
42 }
43
44 static struct clk_ops sh4_module_clk_ops = {
45 .recalc = module_clk_recalc,
46 };
47
bus_clk_recalc(struct clk * clk)48 static unsigned long bus_clk_recalc(struct clk *clk)
49 {
50 int idx = (__raw_readw(FRQCR) >> 3) & 0x0007;
51 return clk->parent->rate / bfc_divisors[idx];
52 }
53
54 static struct clk_ops sh4_bus_clk_ops = {
55 .recalc = bus_clk_recalc,
56 };
57
cpu_clk_recalc(struct clk * clk)58 static unsigned long cpu_clk_recalc(struct clk *clk)
59 {
60 int idx = (__raw_readw(FRQCR) >> 6) & 0x0007;
61 return clk->parent->rate / ifc_divisors[idx];
62 }
63
64 static struct clk_ops sh4_cpu_clk_ops = {
65 .recalc = cpu_clk_recalc,
66 };
67
68 static struct clk_ops *sh4_clk_ops[] = {
69 &sh4_master_clk_ops,
70 &sh4_module_clk_ops,
71 &sh4_bus_clk_ops,
72 &sh4_cpu_clk_ops,
73 };
74
arch_init_clk_ops(struct clk_ops ** ops,int idx)75 void __init arch_init_clk_ops(struct clk_ops **ops, int idx)
76 {
77 if (idx < ARRAY_SIZE(sh4_clk_ops))
78 *ops = sh4_clk_ops[idx];
79 }
80
81