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
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
|
/*
* This file is subject to the terms and conditions of the GNU General Public
* License. See the file "COPYING" in the main directory of this archive
* for more details.
*
* Copyright (C) 2008 Maxime Bizon <mbizon@freebox.fr>
*/
#include <linux/kernel.h>
#include <linux/err.h>
#include <linux/module.h>
#include <linux/spinlock.h>
#include <linux/interrupt.h>
#include <linux/clk.h>
#include <bcm63xx_cpu.h>
#include <bcm63xx_io.h>
#include <bcm63xx_timer.h>
#include <bcm63xx_regs.h>
static DEFINE_RAW_SPINLOCK(timer_reg_lock);
static DEFINE_RAW_SPINLOCK(timer_data_lock);
static struct clk *periph_clk;
static struct timer_data {
void (*cb)(void *);
void *data;
} timer_data[BCM63XX_TIMER_COUNT];
static irqreturn_t timer_interrupt(int irq, void *dev_id)
{
u32 stat;
int i;
raw_spin_lock(&timer_reg_lock);
stat = bcm_timer_readl(TIMER_IRQSTAT_REG);
bcm_timer_writel(stat, TIMER_IRQSTAT_REG);
raw_spin_unlock(&timer_reg_lock);
for (i = 0; i < BCM63XX_TIMER_COUNT; i++) {
if (!(stat & TIMER_IRQSTAT_TIMER_CAUSE(i)))
continue;
raw_spin_lock(&timer_data_lock);
if (!timer_data[i].cb) {
raw_spin_unlock(&timer_data_lock);
continue;
}
timer_data[i].cb(timer_data[i].data);
raw_spin_unlock(&timer_data_lock);
}
return IRQ_HANDLED;
}
int bcm63xx_timer_enable(int id)
{
u32 reg;
unsigned long flags;
if (id >= BCM63XX_TIMER_COUNT)
return -EINVAL;
raw_spin_lock_irqsave(&timer_reg_lock, flags);
reg = bcm_timer_readl(TIMER_CTLx_REG(id));
reg |= TIMER_CTL_ENABLE_MASK;
bcm_timer_writel(reg, TIMER_CTLx_REG(id));
reg = bcm_timer_readl(TIMER_IRQSTAT_REG);
reg |= TIMER_IRQSTAT_TIMER_IR_EN(id);
bcm_timer_writel(reg, TIMER_IRQSTAT_REG);
raw_spin_unlock_irqrestore(&timer_reg_lock, flags);
return 0;
}
EXPORT_SYMBOL(bcm63xx_timer_enable);
int bcm63xx_timer_disable(int id)
{
u32 reg;
unsigned long flags;
if (id >= BCM63XX_TIMER_COUNT)
return -EINVAL;
raw_spin_lock_irqsave(&timer_reg_lock, flags);
reg = bcm_timer_readl(TIMER_CTLx_REG(id));
reg &= ~TIMER_CTL_ENABLE_MASK;
bcm_timer_writel(reg, TIMER_CTLx_REG(id));
reg = bcm_timer_readl(TIMER_IRQSTAT_REG);
reg &= ~TIMER_IRQSTAT_TIMER_IR_EN(id);
bcm_timer_writel(reg, TIMER_IRQSTAT_REG);
raw_spin_unlock_irqrestore(&timer_reg_lock, flags);
return 0;
}
EXPORT_SYMBOL(bcm63xx_timer_disable);
int bcm63xx_timer_register(int id, void (*callback)(void *data), void *data)
{
unsigned long flags;
int ret;
if (id >= BCM63XX_TIMER_COUNT || !callback)
return -EINVAL;
ret = 0;
raw_spin_lock_irqsave(&timer_data_lock, flags);
if (timer_data[id].cb) {
ret = -EBUSY;
goto out;
}
timer_data[id].cb = callback;
timer_data[id].data = data;
out:
raw_spin_unlock_irqrestore(&timer_data_lock, flags);
return ret;
}
EXPORT_SYMBOL(bcm63xx_timer_register);
void bcm63xx_timer_unregister(int id)
{
unsigned long flags;
if (id >= BCM63XX_TIMER_COUNT)
return;
raw_spin_lock_irqsave(&timer_data_lock, flags);
timer_data[id].cb = NULL;
raw_spin_unlock_irqrestore(&timer_data_lock, flags);
}
EXPORT_SYMBOL(bcm63xx_timer_unregister);
unsigned int bcm63xx_timer_countdown(unsigned int countdown_us)
{
return (clk_get_rate(periph_clk) / (1000 * 1000)) * countdown_us;
}
EXPORT_SYMBOL(bcm63xx_timer_countdown);
int bcm63xx_timer_set(int id, int monotonic, unsigned int countdown_us)
{
u32 reg, countdown;
unsigned long flags;
if (id >= BCM63XX_TIMER_COUNT)
return -EINVAL;
countdown = bcm63xx_timer_countdown(countdown_us);
if (countdown & ~TIMER_CTL_COUNTDOWN_MASK)
return -EINVAL;
raw_spin_lock_irqsave(&timer_reg_lock, flags);
reg = bcm_timer_readl(TIMER_CTLx_REG(id));
if (monotonic)
reg &= ~TIMER_CTL_MONOTONIC_MASK;
else
reg |= TIMER_CTL_MONOTONIC_MASK;
reg &= ~TIMER_CTL_COUNTDOWN_MASK;
reg |= countdown;
bcm_timer_writel(reg, TIMER_CTLx_REG(id));
raw_spin_unlock_irqrestore(&timer_reg_lock, flags);
return 0;
}
EXPORT_SYMBOL(bcm63xx_timer_set);
int bcm63xx_timer_init(void)
{
int ret, irq;
u32 reg;
reg = bcm_timer_readl(TIMER_IRQSTAT_REG);
reg &= ~TIMER_IRQSTAT_TIMER0_IR_EN;
reg &= ~TIMER_IRQSTAT_TIMER1_IR_EN;
reg &= ~TIMER_IRQSTAT_TIMER2_IR_EN;
bcm_timer_writel(reg, TIMER_IRQSTAT_REG);
periph_clk = clk_get(NULL, "periph");
if (IS_ERR(periph_clk))
return -ENODEV;
irq = bcm63xx_get_irq_number(IRQ_TIMER);
ret = request_irq(irq, timer_interrupt, 0, "bcm63xx_timer", NULL);
if (ret) {
printk(KERN_ERR "bcm63xx_timer: failed to register irq\n");
return ret;
}
return 0;
}
arch_initcall(bcm63xx_timer_init);
|
