1 /*
2 * Copyright (c) 2016 Yang Ling <gnaygnil@gmail.com>
3 *
4 * This program is free software; you can redistribute it and/or modify it
5 * under the terms of the GNU General Public License as published by the
6 * Free Software Foundation; either version 2 of the License, or (at your
7 * option) any later version.
8 */
9
10 #include <linux/clkdev.h>
11 #include <linux/clk-provider.h>
12
13 #include <loongson1.h>
14 #include "clk.h"
15
16 #define OSC (24 * 1000000)
17 #define DIV_APB 1
18
19 static DEFINE_SPINLOCK(_lock);
20
ls1x_pll_recalc_rate(struct clk_hw * hw,unsigned long parent_rate)21 static unsigned long ls1x_pll_recalc_rate(struct clk_hw *hw,
22 unsigned long parent_rate)
23 {
24 u32 pll, rate;
25
26 pll = __raw_readl(LS1X_CLK_PLL_FREQ);
27 rate = ((pll >> 8) & 0xff) + ((pll >> 16) & 0xff);
28 rate *= OSC;
29 rate >>= 2;
30
31 return rate;
32 }
33
34 static const struct clk_ops ls1x_pll_clk_ops = {
35 .recalc_rate = ls1x_pll_recalc_rate,
36 };
37
38 static const struct clk_div_table ahb_div_table[] = {
39 [0] = { .val = 0, .div = 2 },
40 [1] = { .val = 1, .div = 4 },
41 [2] = { .val = 2, .div = 3 },
42 [3] = { .val = 3, .div = 3 },
43 };
44
ls1x_clk_init(void)45 void __init ls1x_clk_init(void)
46 {
47 struct clk_hw *hw;
48
49 hw = clk_hw_register_fixed_rate(NULL, "osc_clk", NULL, 0, OSC);
50 clk_hw_register_clkdev(hw, "osc_clk", NULL);
51
52 /* clock derived from 24 MHz OSC clk */
53 hw = clk_hw_register_pll(NULL, "pll_clk", "osc_clk",
54 &ls1x_pll_clk_ops, 0);
55 clk_hw_register_clkdev(hw, "pll_clk", NULL);
56
57 hw = clk_hw_register_divider(NULL, "cpu_clk_div", "pll_clk",
58 CLK_GET_RATE_NOCACHE, LS1X_CLK_PLL_DIV,
59 DIV_CPU_SHIFT, DIV_CPU_WIDTH,
60 CLK_DIVIDER_ONE_BASED |
61 CLK_DIVIDER_ROUND_CLOSEST, &_lock);
62 clk_hw_register_clkdev(hw, "cpu_clk_div", NULL);
63 hw = clk_hw_register_fixed_factor(NULL, "cpu_clk", "cpu_clk_div",
64 0, 1, 1);
65 clk_hw_register_clkdev(hw, "cpu_clk", NULL);
66
67 hw = clk_hw_register_divider(NULL, "dc_clk_div", "pll_clk",
68 0, LS1X_CLK_PLL_DIV, DIV_DC_SHIFT,
69 DIV_DC_WIDTH, CLK_DIVIDER_ONE_BASED, &_lock);
70 clk_hw_register_clkdev(hw, "dc_clk_div", NULL);
71 hw = clk_hw_register_fixed_factor(NULL, "dc_clk", "dc_clk_div",
72 0, 1, 1);
73 clk_hw_register_clkdev(hw, "dc_clk", NULL);
74
75 hw = clk_hw_register_divider_table(NULL, "ahb_clk_div", "cpu_clk_div",
76 0, LS1X_CLK_PLL_FREQ, DIV_DDR_SHIFT,
77 DIV_DDR_WIDTH, CLK_DIVIDER_ALLOW_ZERO,
78 ahb_div_table, &_lock);
79 clk_hw_register_clkdev(hw, "ahb_clk_div", NULL);
80 hw = clk_hw_register_fixed_factor(NULL, "ahb_clk", "ahb_clk_div",
81 0, 1, 1);
82 clk_hw_register_clkdev(hw, "ahb_clk", NULL);
83 clk_hw_register_clkdev(hw, "ls1x-dma", NULL);
84 clk_hw_register_clkdev(hw, "stmmaceth", NULL);
85
86 /* clock derived from AHB clk */
87 hw = clk_hw_register_fixed_factor(NULL, "apb_clk", "ahb_clk", 0, 1,
88 DIV_APB);
89 clk_hw_register_clkdev(hw, "apb_clk", NULL);
90 clk_hw_register_clkdev(hw, "ls1x-ac97", NULL);
91 clk_hw_register_clkdev(hw, "ls1x-i2c", NULL);
92 clk_hw_register_clkdev(hw, "ls1x-nand", NULL);
93 clk_hw_register_clkdev(hw, "ls1x-pwmtimer", NULL);
94 clk_hw_register_clkdev(hw, "ls1x-spi", NULL);
95 clk_hw_register_clkdev(hw, "ls1x-wdt", NULL);
96 clk_hw_register_clkdev(hw, "serial8250", NULL);
97 }
98
