1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  * arch/sh/kernel/cpu/sh2a/clock-sh7269.c
4  *
5  * SH7269 clock framework support
6  *
7  * Copyright (C) 2012  Phil Edworthy
8  */
9 #include <linux/init.h>
10 #include <linux/kernel.h>
11 #include <linux/io.h>
12 #include <linux/clkdev.h>
13 #include <asm/clock.h>
14 
15 /* SH7269 registers */
16 #define FRQCR		0xfffe0010
17 #define STBCR3 		0xfffe0408
18 #define STBCR4 		0xfffe040c
19 #define STBCR5 		0xfffe0410
20 #define STBCR6 		0xfffe0414
21 #define STBCR7 		0xfffe0418
22 
23 #define PLL_RATE 20
24 
25 /* Fixed 32 KHz root clock for RTC */
26 static struct clk r_clk = {
27 	.rate           = 32768,
28 };
29 
30 /*
31  * Default rate for the root input clock, reset this with clk_set_rate()
32  * from the platform code.
33  */
34 static struct clk extal_clk = {
35 	.rate		= 13340000,
36 };
37 
pll_recalc(struct clk * clk)38 static unsigned long pll_recalc(struct clk *clk)
39 {
40 	return clk->parent->rate * PLL_RATE;
41 }
42 
43 static struct sh_clk_ops pll_clk_ops = {
44 	.recalc		= pll_recalc,
45 };
46 
47 static struct clk pll_clk = {
48 	.ops		= &pll_clk_ops,
49 	.parent		= &extal_clk,
50 	.flags		= CLK_ENABLE_ON_INIT,
51 };
52 
peripheral0_recalc(struct clk * clk)53 static unsigned long peripheral0_recalc(struct clk *clk)
54 {
55 	return clk->parent->rate / 8;
56 }
57 
58 static struct sh_clk_ops peripheral0_clk_ops = {
59 	.recalc		= peripheral0_recalc,
60 };
61 
62 static struct clk peripheral0_clk = {
63 	.ops		= &peripheral0_clk_ops,
64 	.parent		= &pll_clk,
65 	.flags		= CLK_ENABLE_ON_INIT,
66 };
67 
peripheral1_recalc(struct clk * clk)68 static unsigned long peripheral1_recalc(struct clk *clk)
69 {
70 	return clk->parent->rate / 4;
71 }
72 
73 static struct sh_clk_ops peripheral1_clk_ops = {
74 	.recalc		= peripheral1_recalc,
75 };
76 
77 static struct clk peripheral1_clk = {
78 	.ops		= &peripheral1_clk_ops,
79 	.parent		= &pll_clk,
80 	.flags		= CLK_ENABLE_ON_INIT,
81 };
82 
83 struct clk *main_clks[] = {
84 	&r_clk,
85 	&extal_clk,
86 	&pll_clk,
87 	&peripheral0_clk,
88 	&peripheral1_clk,
89 };
90 
91 static int div2[] = { 1, 2, 0, 4 };
92 
93 static struct clk_div_mult_table div4_div_mult_table = {
94 	.divisors = div2,
95 	.nr_divisors = ARRAY_SIZE(div2),
96 };
97 
98 static struct clk_div4_table div4_table = {
99 	.div_mult_table = &div4_div_mult_table,
100 };
101 
102 enum { DIV4_I, DIV4_B,
103        DIV4_NR };
104 
105 #define DIV4(_reg, _bit, _mask, _flags) \
106   SH_CLK_DIV4(&pll_clk, _reg, _bit, _mask, _flags)
107 
108 /* The mask field specifies the div2 entries that are valid */
109 struct clk div4_clks[DIV4_NR] = {
110 	[DIV4_I]  = DIV4(FRQCR, 8, 0xB, CLK_ENABLE_REG_16BIT
111 					| CLK_ENABLE_ON_INIT),
112 	[DIV4_B]  = DIV4(FRQCR, 4, 0xA, CLK_ENABLE_REG_16BIT
113 					| CLK_ENABLE_ON_INIT),
114 };
115 
116 enum { MSTP72,
117 	MSTP60,
118 	MSTP47, MSTP46, MSTP45, MSTP44, MSTP43, MSTP42, MSTP41, MSTP40,
119 	MSTP35, MSTP32, MSTP30,
120 	MSTP_NR };
121 
122 static struct clk mstp_clks[MSTP_NR] = {
123 	[MSTP72] = SH_CLK_MSTP8(&peripheral0_clk, STBCR7, 2, 0), /* CMT */
124 	[MSTP60] = SH_CLK_MSTP8(&peripheral1_clk, STBCR6, 0, 0), /* USB */
125 	[MSTP47] = SH_CLK_MSTP8(&peripheral1_clk, STBCR4, 7, 0), /* SCIF0 */
126 	[MSTP46] = SH_CLK_MSTP8(&peripheral1_clk, STBCR4, 6, 0), /* SCIF1 */
127 	[MSTP45] = SH_CLK_MSTP8(&peripheral1_clk, STBCR4, 5, 0), /* SCIF2 */
128 	[MSTP44] = SH_CLK_MSTP8(&peripheral1_clk, STBCR4, 4, 0), /* SCIF3 */
129 	[MSTP43] = SH_CLK_MSTP8(&peripheral1_clk, STBCR4, 3, 0), /* SCIF4 */
130 	[MSTP42] = SH_CLK_MSTP8(&peripheral1_clk, STBCR4, 2, 0), /* SCIF5 */
131 	[MSTP41] = SH_CLK_MSTP8(&peripheral1_clk, STBCR4, 1, 0), /* SCIF6 */
132 	[MSTP40] = SH_CLK_MSTP8(&peripheral1_clk, STBCR4, 0, 0), /* SCIF7 */
133 	[MSTP35] = SH_CLK_MSTP8(&peripheral0_clk, STBCR3, 5, 0), /* MTU2 */
134 	[MSTP32] = SH_CLK_MSTP8(&peripheral1_clk, STBCR3, 2, 0), /* ADC */
135 	[MSTP30] = SH_CLK_MSTP8(&r_clk, STBCR3, 0, 0), /* RTC */
136 };
137 
138 static struct clk_lookup lookups[] = {
139 	/* main clocks */
140 	CLKDEV_CON_ID("rclk", &r_clk),
141 	CLKDEV_CON_ID("extal", &extal_clk),
142 	CLKDEV_CON_ID("pll_clk", &pll_clk),
143 	CLKDEV_CON_ID("peripheral_clk", &peripheral1_clk),
144 
145 	/* DIV4 clocks */
146 	CLKDEV_CON_ID("cpu_clk", &div4_clks[DIV4_I]),
147 	CLKDEV_CON_ID("bus_clk", &div4_clks[DIV4_B]),
148 
149 	/* MSTP clocks */
150 	CLKDEV_ICK_ID("fck", "sh-sci.0", &mstp_clks[MSTP47]),
151 	CLKDEV_ICK_ID("fck", "sh-sci.1", &mstp_clks[MSTP46]),
152 	CLKDEV_ICK_ID("fck", "sh-sci.2", &mstp_clks[MSTP45]),
153 	CLKDEV_ICK_ID("fck", "sh-sci.3", &mstp_clks[MSTP44]),
154 	CLKDEV_ICK_ID("fck", "sh-sci.4", &mstp_clks[MSTP43]),
155 	CLKDEV_ICK_ID("fck", "sh-sci.5", &mstp_clks[MSTP42]),
156 	CLKDEV_ICK_ID("fck", "sh-sci.6", &mstp_clks[MSTP41]),
157 	CLKDEV_ICK_ID("fck", "sh-sci.7", &mstp_clks[MSTP40]),
158 	CLKDEV_ICK_ID("fck", "sh-cmt-16.0", &mstp_clks[MSTP72]),
159 	CLKDEV_CON_ID("usb0", &mstp_clks[MSTP60]),
160 	CLKDEV_ICK_ID("fck", "sh-mtu2", &mstp_clks[MSTP35]),
161 	CLKDEV_CON_ID("adc0", &mstp_clks[MSTP32]),
162 	CLKDEV_CON_ID("rtc0", &mstp_clks[MSTP30]),
163 };
164 
arch_clk_init(void)165 int __init arch_clk_init(void)
166 {
167 	int k, ret = 0;
168 
169 	for (k = 0; !ret && (k < ARRAY_SIZE(main_clks)); k++)
170 		ret = clk_register(main_clks[k]);
171 
172 	clkdev_add_table(lookups, ARRAY_SIZE(lookups));
173 
174 	if (!ret)
175 		ret = sh_clk_div4_register(div4_clks, DIV4_NR, &div4_table);
176 
177 	if (!ret)
178 		ret = sh_clk_mstp_register(mstp_clks, MSTP_NR);
179 
180 	return ret;
181 }
182