1/*
2 * arch/sh/kernel/cpu/sh2a/clock-sh7264.c
3 *
4 * SH7264 clock framework support
5 *
6 * Copyright (C) 2012  Phil Edworthy
7 *
8 * This file is subject to the terms and conditions of the GNU General Public
9 * License.  See the file "COPYING" in the main directory of this archive
10 * for more details.
11 */
12#include <linux/init.h>
13#include <linux/kernel.h>
14#include <linux/io.h>
15#include <linux/clkdev.h>
16#include <asm/clock.h>
17
18/* SH7264 registers */
19#define FRQCR		0xfffe0010
20#define STBCR3		0xfffe0408
21#define STBCR4		0xfffe040c
22#define STBCR5		0xfffe0410
23#define STBCR6		0xfffe0414
24#define STBCR7		0xfffe0418
25#define STBCR8		0xfffe041c
26
27static const unsigned int pll1rate[] = {8, 12};
28
29static unsigned int pll1_div;
30
31/* Fixed 32 KHz root clock for RTC */
32static struct clk r_clk = {
33	.rate           = 32768,
34};
35
36/*
37 * Default rate for the root input clock, reset this with clk_set_rate()
38 * from the platform code.
39 */
40static struct clk extal_clk = {
41	.rate		= 18000000,
42};
43
44static unsigned long pll_recalc(struct clk *clk)
45{
46	unsigned long rate = clk->parent->rate / pll1_div;
47	return rate * pll1rate[(__raw_readw(FRQCR) >> 8) & 1];
48}
49
50static struct sh_clk_ops pll_clk_ops = {
51	.recalc		= pll_recalc,
52};
53
54static struct clk pll_clk = {
55	.ops		= &pll_clk_ops,
56	.parent		= &extal_clk,
57	.flags		= CLK_ENABLE_ON_INIT,
58};
59
60struct clk *main_clks[] = {
61	&r_clk,
62	&extal_clk,
63	&pll_clk,
64};
65
66static int div2[] = { 1, 2, 3, 4, 6, 8, 12 };
67
68static struct clk_div_mult_table div4_div_mult_table = {
69	.divisors = div2,
70	.nr_divisors = ARRAY_SIZE(div2),
71};
72
73static struct clk_div4_table div4_table = {
74	.div_mult_table = &div4_div_mult_table,
75};
76
77enum { DIV4_I, DIV4_P,
78       DIV4_NR };
79
80#define DIV4(_reg, _bit, _mask, _flags) \
81  SH_CLK_DIV4(&pll_clk, _reg, _bit, _mask, _flags)
82
83/* The mask field specifies the div2 entries that are valid */
84struct clk div4_clks[DIV4_NR] = {
85	[DIV4_I] = DIV4(FRQCR, 4, 0x7,  CLK_ENABLE_REG_16BIT
86					| CLK_ENABLE_ON_INIT),
87	[DIV4_P] = DIV4(FRQCR, 0, 0x78, CLK_ENABLE_REG_16BIT),
88};
89
90enum {	MSTP77, MSTP74, MSTP72,
91	MSTP60,
92	MSTP35, MSTP34, MSTP33, MSTP32, MSTP30,
93	MSTP_NR };
94
95static struct clk mstp_clks[MSTP_NR] = {
96	[MSTP77] = SH_CLK_MSTP8(&div4_clks[DIV4_P], STBCR7, 7, 0), /* SCIF */
97	[MSTP74] = SH_CLK_MSTP8(&div4_clks[DIV4_P], STBCR7, 4, 0), /* VDC */
98	[MSTP72] = SH_CLK_MSTP8(&div4_clks[DIV4_P], STBCR7, 2, 0), /* CMT */
99	[MSTP60] = SH_CLK_MSTP8(&div4_clks[DIV4_P], STBCR6, 0, 0), /* USB */
100	[MSTP35] = SH_CLK_MSTP8(&div4_clks[DIV4_P], STBCR3, 6, 0), /* MTU2 */
101	[MSTP34] = SH_CLK_MSTP8(&div4_clks[DIV4_P], STBCR3, 4, 0), /* SDHI0 */
102	[MSTP33] = SH_CLK_MSTP8(&div4_clks[DIV4_P], STBCR3, 3, 0), /* SDHI1 */
103	[MSTP32] = SH_CLK_MSTP8(&div4_clks[DIV4_P], STBCR3, 2, 0), /* ADC */
104	[MSTP30] = SH_CLK_MSTP8(&r_clk, STBCR3, 0, 0),	/* RTC */
105};
106
107static struct clk_lookup lookups[] = {
108	/* main clocks */
109	CLKDEV_CON_ID("rclk", &r_clk),
110	CLKDEV_CON_ID("extal", &extal_clk),
111	CLKDEV_CON_ID("pll_clk", &pll_clk),
112
113	/* DIV4 clocks */
114	CLKDEV_CON_ID("cpu_clk", &div4_clks[DIV4_I]),
115	CLKDEV_CON_ID("peripheral_clk", &div4_clks[DIV4_P]),
116
117	/* MSTP clocks */
118	CLKDEV_CON_ID("sci_ick", &mstp_clks[MSTP77]),
119	CLKDEV_CON_ID("vdc3", &mstp_clks[MSTP74]),
120	CLKDEV_ICK_ID("fck", "sh-cmt-16.0", &mstp_clks[MSTP72]),
121	CLKDEV_CON_ID("usb0", &mstp_clks[MSTP60]),
122	CLKDEV_ICK_ID("fck", "sh-mtu2", &mstp_clks[MSTP35]),
123	CLKDEV_CON_ID("sdhi0", &mstp_clks[MSTP34]),
124	CLKDEV_CON_ID("sdhi1", &mstp_clks[MSTP33]),
125	CLKDEV_CON_ID("adc0", &mstp_clks[MSTP32]),
126	CLKDEV_CON_ID("rtc0", &mstp_clks[MSTP30]),
127};
128
129int __init arch_clk_init(void)
130{
131	int k, ret = 0;
132
133	if (test_mode_pin(MODE_PIN0)) {
134		if (test_mode_pin(MODE_PIN1))
135			pll1_div = 3;
136		else
137			pll1_div = 4;
138	} else
139		pll1_div = 1;
140
141	for (k = 0; !ret && (k < ARRAY_SIZE(main_clks)); k++)
142		ret = clk_register(main_clks[k]);
143
144	clkdev_add_table(lookups, ARRAY_SIZE(lookups));
145
146	if (!ret)
147		ret = sh_clk_div4_register(div4_clks, DIV4_NR, &div4_table);
148
149	if (!ret)
150		ret = sh_clk_mstp_register(mstp_clks, MSTP_NR);
151
152	return ret;
153}
154