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
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
|
/*
*
* Copyright (C) 2007 Google, Inc.
* Copyright (c) 2009-2011, Code Aurora Forum. All rights reserved.
*
* This software is licensed under the terms of the GNU General Public
* License version 2, as published by the Free Software Foundation, and
* may be copied, distributed, and modified under those terms.
*
* 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.
*
*/
#include <linux/clocksource.h>
#include <linux/clockchips.h>
#include <linux/init.h>
#include <linux/interrupt.h>
#include <linux/irq.h>
#include <linux/io.h>
#include <asm/mach/time.h>
#include <asm/hardware/gic.h>
#include <asm/localtimer.h>
#include <mach/msm_iomap.h>
#include <mach/cpu.h>
#include <mach/board.h>
#define TIMER_MATCH_VAL 0x0000
#define TIMER_COUNT_VAL 0x0004
#define TIMER_ENABLE 0x0008
#define TIMER_ENABLE_CLR_ON_MATCH_EN BIT(1)
#define TIMER_ENABLE_EN BIT(0)
#define TIMER_CLEAR 0x000C
#define DGT_CLK_CTL 0x0034
#define DGT_CLK_CTL_DIV_4 0x3
#define GPT_HZ 32768
#define MSM_DGT_SHIFT 5
static void __iomem *event_base;
static irqreturn_t msm_timer_interrupt(int irq, void *dev_id)
{
struct clock_event_device *evt = *(struct clock_event_device **)dev_id;
if (evt->event_handler == NULL)
return IRQ_HANDLED;
/* Stop the timer tick */
if (evt->mode == CLOCK_EVT_MODE_ONESHOT) {
u32 ctrl = readl_relaxed(event_base + TIMER_ENABLE);
ctrl &= ~TIMER_ENABLE_EN;
writel_relaxed(ctrl, event_base + TIMER_ENABLE);
}
evt->event_handler(evt);
return IRQ_HANDLED;
}
static int msm_timer_set_next_event(unsigned long cycles,
struct clock_event_device *evt)
{
u32 ctrl = readl_relaxed(event_base + TIMER_ENABLE);
writel_relaxed(0, event_base + TIMER_CLEAR);
writel_relaxed(cycles, event_base + TIMER_MATCH_VAL);
writel_relaxed(ctrl | TIMER_ENABLE_EN, event_base + TIMER_ENABLE);
return 0;
}
static void msm_timer_set_mode(enum clock_event_mode mode,
struct clock_event_device *evt)
{
u32 ctrl;
ctrl = readl_relaxed(event_base + TIMER_ENABLE);
ctrl &= ~(TIMER_ENABLE_EN | TIMER_ENABLE_CLR_ON_MATCH_EN);
switch (mode) {
case CLOCK_EVT_MODE_RESUME:
case CLOCK_EVT_MODE_PERIODIC:
break;
case CLOCK_EVT_MODE_ONESHOT:
/* Timer is enabled in set_next_event */
break;
case CLOCK_EVT_MODE_UNUSED:
case CLOCK_EVT_MODE_SHUTDOWN:
break;
}
writel_relaxed(ctrl, event_base + TIMER_ENABLE);
}
static struct clock_event_device msm_clockevent = {
.name = "gp_timer",
.features = CLOCK_EVT_FEAT_ONESHOT,
.shift = 32,
.rating = 200,
.set_next_event = msm_timer_set_next_event,
.set_mode = msm_timer_set_mode,
};
static union {
struct clock_event_device *evt;
struct clock_event_device __percpu **percpu_evt;
} msm_evt;
static void __iomem *source_base;
static cycle_t msm_read_timer_count(struct clocksource *cs)
{
return readl_relaxed(source_base + TIMER_COUNT_VAL);
}
static cycle_t msm_read_timer_count_shift(struct clocksource *cs)
{
/*
* Shift timer count down by a constant due to unreliable lower bits
* on some targets.
*/
return msm_read_timer_count(cs) >> MSM_DGT_SHIFT;
}
static struct clocksource msm_clocksource = {
.name = "dg_timer",
.rating = 300,
.read = msm_read_timer_count,
.mask = CLOCKSOURCE_MASK(32),
.flags = CLOCK_SOURCE_IS_CONTINUOUS,
};
static void __init msm_timer_init(void)
{
struct clock_event_device *ce = &msm_clockevent;
struct clocksource *cs = &msm_clocksource;
int res;
u32 dgt_hz;
if (cpu_is_msm7x01()) {
event_base = MSM_CSR_BASE;
source_base = MSM_CSR_BASE + 0x10;
dgt_hz = 19200000 >> MSM_DGT_SHIFT; /* 600 KHz */
cs->read = msm_read_timer_count_shift;
cs->mask = CLOCKSOURCE_MASK((32 - MSM_DGT_SHIFT));
} else if (cpu_is_msm7x30()) {
event_base = MSM_CSR_BASE + 0x04;
source_base = MSM_CSR_BASE + 0x24;
dgt_hz = 24576000 / 4;
} else if (cpu_is_qsd8x50()) {
event_base = MSM_CSR_BASE;
source_base = MSM_CSR_BASE + 0x10;
dgt_hz = 19200000 / 4;
} else if (cpu_is_msm8x60() || cpu_is_msm8960()) {
event_base = MSM_TMR_BASE + 0x04;
/* Use CPU0's timer as the global clock source. */
source_base = MSM_TMR0_BASE + 0x24;
dgt_hz = 27000000 / 4;
writel_relaxed(DGT_CLK_CTL_DIV_4, MSM_TMR_BASE + DGT_CLK_CTL);
} else
BUG();
writel_relaxed(0, event_base + TIMER_ENABLE);
writel_relaxed(0, event_base + TIMER_CLEAR);
writel_relaxed(~0, event_base + TIMER_MATCH_VAL);
ce->mult = div_sc(GPT_HZ, NSEC_PER_SEC, ce->shift);
/*
* allow at least 10 seconds to notice that the timer
* wrapped
*/
ce->max_delta_ns = clockevent_delta2ns(0xf0000000, ce);
/* 4 gets rounded down to 3 */
ce->min_delta_ns = clockevent_delta2ns(4, ce);
ce->cpumask = cpumask_of(0);
ce->irq = INT_GP_TIMER_EXP;
if (cpu_is_msm8x60() || cpu_is_msm8960()) {
msm_evt.percpu_evt = alloc_percpu(struct clock_event_device *);
if (!msm_evt.percpu_evt) {
pr_err("memory allocation failed for %s\n", ce->name);
goto err;
}
*__this_cpu_ptr(msm_evt.percpu_evt) = ce;
res = request_percpu_irq(ce->irq, msm_timer_interrupt,
ce->name, msm_evt.percpu_evt);
if (!res)
enable_percpu_irq(ce->irq, 0);
} else {
msm_evt.evt = ce;
res = request_irq(ce->irq, msm_timer_interrupt,
IRQF_TIMER | IRQF_NOBALANCING |
IRQF_TRIGGER_RISING, ce->name, &msm_evt.evt);
}
if (res)
pr_err("request_irq failed for %s\n", ce->name);
clockevents_register_device(ce);
err:
writel_relaxed(TIMER_ENABLE_EN, source_base + TIMER_ENABLE);
res = clocksource_register_hz(cs, dgt_hz);
if (res)
pr_err("clocksource_register failed\n");
}
#ifdef CONFIG_LOCAL_TIMERS
int __cpuinit local_timer_setup(struct clock_event_device *evt)
{
/* Use existing clock_event for cpu 0 */
if (!smp_processor_id())
return 0;
writel_relaxed(0, event_base + TIMER_ENABLE);
writel_relaxed(0, event_base + TIMER_CLEAR);
writel_relaxed(~0, event_base + TIMER_MATCH_VAL);
evt->irq = msm_clockevent.irq;
evt->name = "local_timer";
evt->features = msm_clockevent.features;
evt->rating = msm_clockevent.rating;
evt->set_mode = msm_timer_set_mode;
evt->set_next_event = msm_timer_set_next_event;
evt->shift = msm_clockevent.shift;
evt->mult = div_sc(GPT_HZ, NSEC_PER_SEC, evt->shift);
evt->max_delta_ns = clockevent_delta2ns(0xf0000000, evt);
evt->min_delta_ns = clockevent_delta2ns(4, evt);
*__this_cpu_ptr(msm_evt.percpu_evt) = evt;
enable_percpu_irq(evt->irq, 0);
clockevents_register_device(evt);
return 0;
}
void local_timer_stop(struct clock_event_device *evt)
{
evt->set_mode(CLOCK_EVT_MODE_UNUSED, evt);
disable_percpu_irq(evt->irq);
}
#endif /* CONFIG_LOCAL_TIMERS */
struct sys_timer msm_timer = {
.init = msm_timer_init
};
|
