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
206
207
208
209
210
211
212
|
// SPDX-License-Identifier: GPL-2.0
/*
* Copyright (C) 2014-2018 Nuvoton Technologies tomer.maimon@nuvoton.com
* All rights reserved.
*
* Copyright 2017 Google, Inc.
*/
#include <linux/kernel.h>
#include <linux/sched.h>
#include <linux/init.h>
#include <linux/interrupt.h>
#include <linux/err.h>
#include <linux/clk.h>
#include <linux/io.h>
#include <linux/clockchips.h>
#include <linux/of_irq.h>
#include <linux/of_address.h>
#include "timer-of.h"
/* Timers registers */
#define NPCM7XX_REG_TCSR0 0x0 /* Timer 0 Control and Status Register */
#define NPCM7XX_REG_TICR0 0x8 /* Timer 0 Initial Count Register */
#define NPCM7XX_REG_TCSR1 0x4 /* Timer 1 Control and Status Register */
#define NPCM7XX_REG_TICR1 0xc /* Timer 1 Initial Count Register */
#define NPCM7XX_REG_TDR1 0x14 /* Timer 1 Data Register */
#define NPCM7XX_REG_TISR 0x18 /* Timer Interrupt Status Register */
/* Timers control */
#define NPCM7XX_Tx_RESETINT 0x1f
#define NPCM7XX_Tx_PERIOD BIT(27)
#define NPCM7XX_Tx_INTEN BIT(29)
#define NPCM7XX_Tx_COUNTEN BIT(30)
#define NPCM7XX_Tx_ONESHOT 0x0
#define NPCM7XX_Tx_OPER GENMASK(28, 27)
#define NPCM7XX_Tx_MIN_PRESCALE 0x1
#define NPCM7XX_Tx_TDR_MASK_BITS 24
#define NPCM7XX_Tx_MAX_CNT 0xFFFFFF
#define NPCM7XX_T0_CLR_INT 0x1
#define NPCM7XX_Tx_CLR_CSR 0x0
/* Timers operating mode */
#define NPCM7XX_START_PERIODIC_Tx (NPCM7XX_Tx_PERIOD | NPCM7XX_Tx_COUNTEN | \
NPCM7XX_Tx_INTEN | \
NPCM7XX_Tx_MIN_PRESCALE)
#define NPCM7XX_START_ONESHOT_Tx (NPCM7XX_Tx_ONESHOT | NPCM7XX_Tx_COUNTEN | \
NPCM7XX_Tx_INTEN | \
NPCM7XX_Tx_MIN_PRESCALE)
#define NPCM7XX_START_Tx (NPCM7XX_Tx_COUNTEN | NPCM7XX_Tx_PERIOD | \
NPCM7XX_Tx_MIN_PRESCALE)
#define NPCM7XX_DEFAULT_CSR (NPCM7XX_Tx_CLR_CSR | NPCM7XX_Tx_MIN_PRESCALE)
static int npcm7xx_timer_resume(struct clock_event_device *evt)
{
struct timer_of *to = to_timer_of(evt);
u32 val;
val = readl(timer_of_base(to) + NPCM7XX_REG_TCSR0);
val |= NPCM7XX_Tx_COUNTEN;
writel(val, timer_of_base(to) + NPCM7XX_REG_TCSR0);
return 0;
}
static int npcm7xx_timer_shutdown(struct clock_event_device *evt)
{
struct timer_of *to = to_timer_of(evt);
u32 val;
val = readl(timer_of_base(to) + NPCM7XX_REG_TCSR0);
val &= ~NPCM7XX_Tx_COUNTEN;
writel(val, timer_of_base(to) + NPCM7XX_REG_TCSR0);
return 0;
}
static int npcm7xx_timer_oneshot(struct clock_event_device *evt)
{
struct timer_of *to = to_timer_of(evt);
u32 val;
val = readl(timer_of_base(to) + NPCM7XX_REG_TCSR0);
val &= ~NPCM7XX_Tx_OPER;
val |= NPCM7XX_START_ONESHOT_Tx;
writel(val, timer_of_base(to) + NPCM7XX_REG_TCSR0);
return 0;
}
static int npcm7xx_timer_periodic(struct clock_event_device *evt)
{
struct timer_of *to = to_timer_of(evt);
u32 val;
writel(timer_of_period(to), timer_of_base(to) + NPCM7XX_REG_TICR0);
val = readl(timer_of_base(to) + NPCM7XX_REG_TCSR0);
val &= ~NPCM7XX_Tx_OPER;
val |= NPCM7XX_START_PERIODIC_Tx;
writel(val, timer_of_base(to) + NPCM7XX_REG_TCSR0);
return 0;
}
static int npcm7xx_clockevent_set_next_event(unsigned long evt,
struct clock_event_device *clk)
{
struct timer_of *to = to_timer_of(clk);
u32 val;
writel(evt, timer_of_base(to) + NPCM7XX_REG_TICR0);
val = readl(timer_of_base(to) + NPCM7XX_REG_TCSR0);
val |= NPCM7XX_START_Tx;
writel(val, timer_of_base(to) + NPCM7XX_REG_TCSR0);
return 0;
}
static irqreturn_t npcm7xx_timer0_interrupt(int irq, void *dev_id)
{
struct clock_event_device *evt = (struct clock_event_device *)dev_id;
struct timer_of *to = to_timer_of(evt);
writel(NPCM7XX_T0_CLR_INT, timer_of_base(to) + NPCM7XX_REG_TISR);
evt->event_handler(evt);
return IRQ_HANDLED;
}
static struct timer_of npcm7xx_to = {
.flags = TIMER_OF_IRQ | TIMER_OF_BASE | TIMER_OF_CLOCK,
.clkevt = {
.name = "npcm7xx-timer0",
.features = CLOCK_EVT_FEAT_PERIODIC |
CLOCK_EVT_FEAT_ONESHOT,
.set_next_event = npcm7xx_clockevent_set_next_event,
.set_state_shutdown = npcm7xx_timer_shutdown,
.set_state_periodic = npcm7xx_timer_periodic,
.set_state_oneshot = npcm7xx_timer_oneshot,
.tick_resume = npcm7xx_timer_resume,
.rating = 300,
},
.of_irq = {
.handler = npcm7xx_timer0_interrupt,
.flags = IRQF_TIMER | IRQF_IRQPOLL,
},
};
static void __init npcm7xx_clockevents_init(void)
{
writel(NPCM7XX_DEFAULT_CSR,
timer_of_base(&npcm7xx_to) + NPCM7XX_REG_TCSR0);
writel(NPCM7XX_Tx_RESETINT,
timer_of_base(&npcm7xx_to) + NPCM7XX_REG_TISR);
npcm7xx_to.clkevt.cpumask = cpumask_of(0);
clockevents_config_and_register(&npcm7xx_to.clkevt,
timer_of_rate(&npcm7xx_to),
0x1, NPCM7XX_Tx_MAX_CNT);
}
static void __init npcm7xx_clocksource_init(void)
{
u32 val;
writel(NPCM7XX_DEFAULT_CSR,
timer_of_base(&npcm7xx_to) + NPCM7XX_REG_TCSR1);
writel(NPCM7XX_Tx_MAX_CNT,
timer_of_base(&npcm7xx_to) + NPCM7XX_REG_TICR1);
val = readl(timer_of_base(&npcm7xx_to) + NPCM7XX_REG_TCSR1);
val |= NPCM7XX_START_Tx;
writel(val, timer_of_base(&npcm7xx_to) + NPCM7XX_REG_TCSR1);
clocksource_mmio_init(timer_of_base(&npcm7xx_to) +
NPCM7XX_REG_TDR1,
"npcm7xx-timer1", timer_of_rate(&npcm7xx_to),
200, (unsigned int)NPCM7XX_Tx_TDR_MASK_BITS,
clocksource_mmio_readl_down);
}
static int __init npcm7xx_timer_init(struct device_node *np)
{
int ret;
ret = timer_of_init(np, &npcm7xx_to);
if (ret)
return ret;
/* Clock input is divided by PRESCALE + 1 before it is fed */
/* to the counter */
npcm7xx_to.of_clk.rate = npcm7xx_to.of_clk.rate /
(NPCM7XX_Tx_MIN_PRESCALE + 1);
npcm7xx_clocksource_init();
npcm7xx_clockevents_init();
pr_info("Enabling NPCM7xx clocksource timer base: %px, IRQ: %d ",
timer_of_base(&npcm7xx_to), timer_of_irq(&npcm7xx_to));
return 0;
}
TIMER_OF_DECLARE(npcm7xx, "nuvoton,npcm750-timer", npcm7xx_timer_init);
|
