1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
|
/*
* Copyright 2011-2012 Calxeda, Inc.
* Copyright (C) 2012-2013 Altera Corporation <www.altera.com>
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* Based from clk-highbank.c
*
* You should have received a copy of the GNU General Public License
* along with this program. If not, see <http://www.gnu.org/licenses/>.
*/
#include <linux/clk.h>
#include <linux/clkdev.h>
#include <linux/clk-provider.h>
#include <linux/io.h>
#include <linux/of.h>
/* Clock Manager offsets */
#define CLKMGR_CTRL 0x0
#define CLKMGR_BYPASS 0x4
/* Clock bypass bits */
#define MAINPLL_BYPASS (1<<0)
#define SDRAMPLL_BYPASS (1<<1)
#define SDRAMPLL_SRC_BYPASS (1<<2)
#define PERPLL_BYPASS (1<<3)
#define PERPLL_SRC_BYPASS (1<<4)
#define SOCFPGA_PLL_BG_PWRDWN 0
#define SOCFPGA_PLL_EXT_ENA 1
#define SOCFPGA_PLL_PWR_DOWN 2
#define SOCFPGA_PLL_DIVF_MASK 0x0000FFF8
#define SOCFPGA_PLL_DIVF_SHIFT 3
#define SOCFPGA_PLL_DIVQ_MASK 0x003F0000
#define SOCFPGA_PLL_DIVQ_SHIFT 16
extern void __iomem *clk_mgr_base_addr;
struct socfpga_clk {
struct clk_gate hw;
char *parent_name;
char *clk_name;
u32 fixed_div;
};
#define to_socfpga_clk(p) container_of(p, struct socfpga_clk, hw.hw)
static unsigned long clk_pll_recalc_rate(struct clk_hw *hwclk,
unsigned long parent_rate)
{
struct socfpga_clk *socfpgaclk = to_socfpga_clk(hwclk);
unsigned long divf, divq, vco_freq, reg;
unsigned long bypass;
reg = readl(socfpgaclk->hw.reg);
bypass = readl(clk_mgr_base_addr + CLKMGR_BYPASS);
if (bypass & MAINPLL_BYPASS)
return parent_rate;
divf = (reg & SOCFPGA_PLL_DIVF_MASK) >> SOCFPGA_PLL_DIVF_SHIFT;
divq = (reg & SOCFPGA_PLL_DIVQ_MASK) >> SOCFPGA_PLL_DIVQ_SHIFT;
vco_freq = parent_rate * (divf + 1);
return vco_freq / (1 + divq);
}
static struct clk_ops clk_pll_ops = {
.recalc_rate = clk_pll_recalc_rate,
};
static unsigned long clk_periclk_recalc_rate(struct clk_hw *hwclk,
unsigned long parent_rate)
{
struct socfpga_clk *socfpgaclk = to_socfpga_clk(hwclk);
u32 div;
if (socfpgaclk->fixed_div)
div = socfpgaclk->fixed_div;
else
div = ((readl(socfpgaclk->hw.reg) & 0x1ff) + 1);
return parent_rate / div;
}
static const struct clk_ops periclk_ops = {
.recalc_rate = clk_periclk_recalc_rate,
};
static __init struct clk *socfpga_clk_init(struct device_node *node,
const struct clk_ops *ops)
{
u32 reg;
struct clk *clk;
struct socfpga_clk *socfpga_clk;
const char *clk_name = node->name;
const char *parent_name;
struct clk_init_data init;
int rc;
u32 fixed_div;
rc = of_property_read_u32(node, "reg", ®);
if (WARN_ON(rc))
return NULL;
socfpga_clk = kzalloc(sizeof(*socfpga_clk), GFP_KERNEL);
if (WARN_ON(!socfpga_clk))
return NULL;
socfpga_clk->hw.reg = clk_mgr_base_addr + reg;
rc = of_property_read_u32(node, "fixed-divider", &fixed_div);
if (rc)
socfpga_clk->fixed_div = 0;
else
socfpga_clk->fixed_div = fixed_div;
of_property_read_string(node, "clock-output-names", &clk_name);
init.name = clk_name;
init.ops = ops;
init.flags = 0;
parent_name = of_clk_get_parent_name(node, 0);
init.parent_names = &parent_name;
init.num_parents = 1;
socfpga_clk->hw.hw.init = &init;
if (strcmp(clk_name, "main_pll") || strcmp(clk_name, "periph_pll") ||
strcmp(clk_name, "sdram_pll")) {
socfpga_clk->hw.bit_idx = SOCFPGA_PLL_EXT_ENA;
clk_pll_ops.enable = clk_gate_ops.enable;
clk_pll_ops.disable = clk_gate_ops.disable;
}
clk = clk_register(NULL, &socfpga_clk->hw.hw);
if (WARN_ON(IS_ERR(clk))) {
kfree(socfpga_clk);
return NULL;
}
rc = of_clk_add_provider(node, of_clk_src_simple_get, clk);
return clk;
}
static void __init socfpga_pll_init(struct device_node *node)
{
socfpga_clk_init(node, &clk_pll_ops);
}
CLK_OF_DECLARE(socfpga_pll, "altr,socfpga-pll-clock", socfpga_pll_init);
static void __init socfpga_periph_init(struct device_node *node)
{
socfpga_clk_init(node, &periclk_ops);
}
CLK_OF_DECLARE(socfpga_periph, "altr,socfpga-perip-clk", socfpga_periph_init);
void __init socfpga_init_clocks(void)
{
struct clk *clk;
int ret;
clk = clk_register_fixed_factor(NULL, "smp_twd", "mpuclk", 0, 1, 4);
ret = clk_register_clkdev(clk, NULL, "smp_twd");
if (ret)
pr_err("smp_twd alias not registered\n");
}
|
