1 // SPDX-License-Identifier: GPL-2.0
2 /*
3 * arch/sh/kernel/cpu/sh4/clock-sh4.c
4 *
5 * Generic SH-4 support for the clock framework
6 *
7 * Copyright (C) 2005 Paul Mundt
8 *
9 * FRQCR parsing hacked out of arch/sh/kernel/time.c
10 *
11 * Copyright (C) 1999 Tetsuya Okada & Niibe Yutaka
12 * Copyright (C) 2000 Philipp Rumpf <prumpf@tux.org>
13 * Copyright (C) 2002, 2003, 2004 Paul Mundt
14 * Copyright (C) 2002 M. R. Brown <mrbrown@linux-sh.org>
15 */
16 #include <linux/init.h>
17 #include <linux/kernel.h>
18 #include <asm/clock.h>
19 #include <asm/freq.h>
20 #include <asm/io.h>
21
22 static int ifc_divisors[] = { 1, 2, 3, 4, 6, 8, 1, 1 };
23 #define bfc_divisors ifc_divisors /* Same */
24 static int pfc_divisors[] = { 2, 3, 4, 6, 8, 2, 2, 2 };
25
master_clk_init(struct clk * clk)26 static void master_clk_init(struct clk *clk)
27 {
28 clk->rate *= pfc_divisors[__raw_readw(FRQCR) & 0x0007];
29 }
30
31 static struct sh_clk_ops sh4_master_clk_ops = {
32 .init = master_clk_init,
33 };
34
module_clk_recalc(struct clk * clk)35 static unsigned long module_clk_recalc(struct clk *clk)
36 {
37 int idx = (__raw_readw(FRQCR) & 0x0007);
38 return clk->parent->rate / pfc_divisors[idx];
39 }
40
41 static struct sh_clk_ops sh4_module_clk_ops = {
42 .recalc = module_clk_recalc,
43 };
44
bus_clk_recalc(struct clk * clk)45 static unsigned long bus_clk_recalc(struct clk *clk)
46 {
47 int idx = (__raw_readw(FRQCR) >> 3) & 0x0007;
48 return clk->parent->rate / bfc_divisors[idx];
49 }
50
51 static struct sh_clk_ops sh4_bus_clk_ops = {
52 .recalc = bus_clk_recalc,
53 };
54
cpu_clk_recalc(struct clk * clk)55 static unsigned long cpu_clk_recalc(struct clk *clk)
56 {
57 int idx = (__raw_readw(FRQCR) >> 6) & 0x0007;
58 return clk->parent->rate / ifc_divisors[idx];
59 }
60
61 static struct sh_clk_ops sh4_cpu_clk_ops = {
62 .recalc = cpu_clk_recalc,
63 };
64
65 static struct sh_clk_ops *sh4_clk_ops[] = {
66 &sh4_master_clk_ops,
67 &sh4_module_clk_ops,
68 &sh4_bus_clk_ops,
69 &sh4_cpu_clk_ops,
70 };
71
arch_init_clk_ops(struct sh_clk_ops ** ops,int idx)72 void __init arch_init_clk_ops(struct sh_clk_ops **ops, int idx)
73 {
74 if (idx < ARRAY_SIZE(sh4_clk_ops))
75 *ops = sh4_clk_ops[idx];
76 }
77
78