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
|
/*
* Loongson2 performance counter driver for oprofile
*
* Copyright (C) 2009 Lemote Inc.
* Author: Yanhua <yanh@lemote.com>
* Author: Wu Zhangjin <wuzj@lemote.com>
*
* 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.
*
*/
#include <linux/init.h>
#include <linux/oprofile.h>
#include <linux/interrupt.h>
#include <loongson.h> /* LOONGSON2_PERFCNT_IRQ */
#include "op_impl.h"
/*
* a patch should be sent to oprofile with the loongson-specific support.
* otherwise, the oprofile tool will not recognize this and complain about
* "cpu_type 'unset' is not valid".
*/
#define LOONGSON2_CPU_TYPE "mips/loongson2"
#define LOONGSON2_COUNTER1_EVENT(event) ((event & 0x0f) << 5)
#define LOONGSON2_COUNTER2_EVENT(event) ((event & 0x0f) << 9)
#define LOONGSON2_PERFCNT_EXL (1UL << 0)
#define LOONGSON2_PERFCNT_KERNEL (1UL << 1)
#define LOONGSON2_PERFCNT_SUPERVISOR (1UL << 2)
#define LOONGSON2_PERFCNT_USER (1UL << 3)
#define LOONGSON2_PERFCNT_INT_EN (1UL << 4)
#define LOONGSON2_PERFCNT_OVERFLOW (1ULL << 31)
/* Loongson2 performance counter register */
#define read_c0_perfctrl() __read_64bit_c0_register($24, 0)
#define write_c0_perfctrl(val) __write_64bit_c0_register($24, 0, val)
#define read_c0_perfcnt() __read_64bit_c0_register($25, 0)
#define write_c0_perfcnt(val) __write_64bit_c0_register($25, 0, val)
static struct loongson2_register_config {
unsigned int ctrl;
unsigned long long reset_counter1;
unsigned long long reset_counter2;
int cnt1_enabled, cnt2_enabled;
} reg;
DEFINE_SPINLOCK(sample_lock);
static char *oprofid = "LoongsonPerf";
static irqreturn_t loongson2_perfcount_handler(int irq, void *dev_id);
/* Compute all of the registers in preparation for enabling profiling. */
static void loongson2_reg_setup(struct op_counter_config *cfg)
{
unsigned int ctrl = 0;
reg.reset_counter1 = 0;
reg.reset_counter2 = 0;
/* Compute the performance counter ctrl word. */
/* For now count kernel and user mode */
if (cfg[0].enabled) {
ctrl |= LOONGSON2_COUNTER1_EVENT(cfg[0].event);
reg.reset_counter1 = 0x80000000ULL - cfg[0].count;
}
if (cfg[1].enabled) {
ctrl |= LOONGSON2_COUNTER2_EVENT(cfg[1].event);
reg.reset_counter2 = (0x80000000ULL - cfg[1].count);
}
if (cfg[0].enabled || cfg[1].enabled) {
ctrl |= LOONGSON2_PERFCNT_EXL | LOONGSON2_PERFCNT_INT_EN;
if (cfg[0].kernel || cfg[1].kernel)
ctrl |= LOONGSON2_PERFCNT_KERNEL;
if (cfg[0].user || cfg[1].user)
ctrl |= LOONGSON2_PERFCNT_USER;
}
reg.ctrl = ctrl;
reg.cnt1_enabled = cfg[0].enabled;
reg.cnt2_enabled = cfg[1].enabled;
}
/* Program all of the registers in preparation for enabling profiling. */
static void loongson2_cpu_setup(void *args)
{
uint64_t perfcount;
perfcount = (reg.reset_counter2 << 32) | reg.reset_counter1;
write_c0_perfcnt(perfcount);
}
static void loongson2_cpu_start(void *args)
{
/* Start all counters on current CPU */
if (reg.cnt1_enabled || reg.cnt2_enabled)
write_c0_perfctrl(reg.ctrl);
}
static void loongson2_cpu_stop(void *args)
{
/* Stop all counters on current CPU */
write_c0_perfctrl(0);
memset(®, 0, sizeof(reg));
}
static irqreturn_t loongson2_perfcount_handler(int irq, void *dev_id)
{
uint64_t counter, counter1, counter2;
struct pt_regs *regs = get_irq_regs();
int enabled;
unsigned long flags;
/*
* LOONGSON2 defines two 32-bit performance counters.
* To avoid a race updating the registers we need to stop the counters
* while we're messing with
* them ...
*/
/* Check whether the irq belongs to me */
enabled = read_c0_perfcnt() & LOONGSON2_PERFCNT_INT_EN;
if (!enabled)
return IRQ_NONE;
enabled = reg.cnt1_enabled | reg.cnt2_enabled;
if (!enabled)
return IRQ_NONE;
counter = read_c0_perfcnt();
counter1 = counter & 0xffffffff;
counter2 = counter >> 32;
spin_lock_irqsave(&sample_lock, flags);
if (counter1 & LOONGSON2_PERFCNT_OVERFLOW) {
if (reg.cnt1_enabled)
oprofile_add_sample(regs, 0);
counter1 = reg.reset_counter1;
}
if (counter2 & LOONGSON2_PERFCNT_OVERFLOW) {
if (reg.cnt2_enabled)
oprofile_add_sample(regs, 1);
counter2 = reg.reset_counter2;
}
spin_unlock_irqrestore(&sample_lock, flags);
write_c0_perfcnt((counter2 << 32) | counter1);
return IRQ_HANDLED;
}
static int __init loongson2_init(void)
{
return request_irq(LOONGSON2_PERFCNT_IRQ, loongson2_perfcount_handler,
IRQF_SHARED, "Perfcounter", oprofid);
}
static void loongson2_exit(void)
{
write_c0_perfctrl(0);
free_irq(LOONGSON2_PERFCNT_IRQ, oprofid);
}
struct op_mips_model op_model_loongson2_ops = {
.reg_setup = loongson2_reg_setup,
.cpu_setup = loongson2_cpu_setup,
.init = loongson2_init,
.exit = loongson2_exit,
.cpu_start = loongson2_cpu_start,
.cpu_stop = loongson2_cpu_stop,
.cpu_type = LOONGSON2_CPU_TYPE,
.num_counters = 2
};
|
