summaryrefslogtreecommitdiffstats
path: root/arch/avr32/oprofile/op_model_avr32.c
blob: f74b7809e089d0bb404f5ea9c0433dbad52212af (plain)
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
/*
 * AVR32 Performance Counter Driver
 *
 * Copyright (C) 2005-2007 Atmel Corporation
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License version 2 as
 * published by the Free Software Foundation.
 *
 * Author: Ronny Pedersen
 */
#include <linux/errno.h>
#include <linux/interrupt.h>
#include <linux/irq.h>
#include <linux/oprofile.h>
#include <linux/sched.h>
#include <linux/types.h>

#include <asm/sysreg.h>

#define AVR32_PERFCTR_IRQ_GROUP	0
#define AVR32_PERFCTR_IRQ_LINE	1

void avr32_backtrace(struct pt_regs * const regs, unsigned int depth);

enum { PCCNT, PCNT0, PCNT1, NR_counter };

struct avr32_perf_counter {
	unsigned long	enabled;
	unsigned long	event;
	unsigned long	count;
	unsigned long	unit_mask;
	unsigned long	kernel;
	unsigned long	user;

	u32		ie_mask;
	u32		flag_mask;
};

static struct avr32_perf_counter counter[NR_counter] = {
	{
		.ie_mask	= SYSREG_BIT(IEC),
		.flag_mask	= SYSREG_BIT(FC),
	}, {
		.ie_mask	= SYSREG_BIT(IE0),
		.flag_mask	= SYSREG_BIT(F0),
	}, {
		.ie_mask	= SYSREG_BIT(IE1),
		.flag_mask	= SYSREG_BIT(F1),
	},
};

static void avr32_perf_counter_reset(void)
{
	/* Reset all counter and disable/clear all interrupts */
	sysreg_write(PCCR, (SYSREG_BIT(PCCR_R)
				| SYSREG_BIT(PCCR_C)
				| SYSREG_BIT(FC)
				| SYSREG_BIT(F0)
				| SYSREG_BIT(F1)));
}

static irqreturn_t avr32_perf_counter_interrupt(int irq, void *dev_id)
{
	struct avr32_perf_counter *ctr = dev_id;
	struct pt_regs *regs;
	u32 pccr;

	if (likely(!(intc_get_pending(AVR32_PERFCTR_IRQ_GROUP)
					& (1 << AVR32_PERFCTR_IRQ_LINE))))
		return IRQ_NONE;

	regs = get_irq_regs();
	pccr = sysreg_read(PCCR);

	/* Clear the interrupt flags we're about to handle */
	sysreg_write(PCCR, pccr);

	/* PCCNT */
	if (ctr->enabled && (pccr & ctr->flag_mask)) {
		sysreg_write(PCCNT, -ctr->count);
		oprofile_add_sample(regs, PCCNT);
	}
	ctr++;
	/* PCNT0 */
	if (ctr->enabled && (pccr & ctr->flag_mask)) {
		sysreg_write(PCNT0, -ctr->count);
		oprofile_add_sample(regs, PCNT0);
	}
	ctr++;
	/* PCNT1 */
	if (ctr->enabled && (pccr & ctr->flag_mask)) {
		sysreg_write(PCNT1, -ctr->count);
		oprofile_add_sample(regs, PCNT1);
	}

	return IRQ_HANDLED;
}

static int avr32_perf_counter_create_files(struct super_block *sb,
		struct dentry *root)
{
	struct dentry *dir;
	unsigned int i;
	char filename[4];

	for (i = 0; i < NR_counter; i++) {
		snprintf(filename, sizeof(filename), "%u", i);
		dir = oprofilefs_mkdir(sb, root, filename);

		oprofilefs_create_ulong(sb, dir, "enabled",
				&counter[i].enabled);
		oprofilefs_create_ulong(sb, dir, "event",
				&counter[i].event);
		oprofilefs_create_ulong(sb, dir, "count",
				&counter[i].count);

		/* Dummy entries */
		oprofilefs_create_ulong(sb, dir, "kernel",
				&counter[i].kernel);
		oprofilefs_create_ulong(sb, dir, "user",
				&counter[i].user);
		oprofilefs_create_ulong(sb, dir, "unit_mask",
				&counter[i].unit_mask);
	}

	return 0;
}

static int avr32_perf_counter_setup(void)
{
	struct avr32_perf_counter *ctr;
	u32 pccr;
	int ret;
	int i;

	pr_debug("avr32_perf_counter_setup\n");

	if (sysreg_read(PCCR) & SYSREG_BIT(PCCR_E)) {
		printk(KERN_ERR
			"oprofile: setup: perf counter already enabled\n");
		return -EBUSY;
	}

	ret = request_irq(AVR32_PERFCTR_IRQ_GROUP,
			avr32_perf_counter_interrupt, IRQF_SHARED,
			"oprofile", counter);
	if (ret)
		return ret;

	avr32_perf_counter_reset();

	pccr = 0;
	for (i = PCCNT; i < NR_counter; i++) {
		ctr = &counter[i];
		if (!ctr->enabled)
			continue;

		pr_debug("enabling counter %d...\n", i);

		pccr |= ctr->ie_mask;

		switch (i) {
		case PCCNT:
			/* PCCNT always counts cycles, so no events */
			sysreg_write(PCCNT, -ctr->count);
			break;
		case PCNT0:
			pccr |= SYSREG_BF(CONF0, ctr->event);
			sysreg_write(PCNT0, -ctr->count);
			break;
		case PCNT1:
			pccr |= SYSREG_BF(CONF1, ctr->event);
			sysreg_write(PCNT1, -ctr->count);
			break;
		}
	}

	pr_debug("oprofile: writing 0x%x to PCCR...\n", pccr);

	sysreg_write(PCCR, pccr);

	return 0;
}

static void avr32_perf_counter_shutdown(void)
{
	pr_debug("avr32_perf_counter_shutdown\n");

	avr32_perf_counter_reset();
	free_irq(AVR32_PERFCTR_IRQ_GROUP, counter);
}

static int avr32_perf_counter_start(void)
{
	pr_debug("avr32_perf_counter_start\n");

	sysreg_write(PCCR, sysreg_read(PCCR) | SYSREG_BIT(PCCR_E));

	return 0;
}

static void avr32_perf_counter_stop(void)
{
	pr_debug("avr32_perf_counter_stop\n");

	sysreg_write(PCCR, sysreg_read(PCCR) & ~SYSREG_BIT(PCCR_E));
}

static struct oprofile_operations avr32_perf_counter_ops __initdata = {
	.create_files	= avr32_perf_counter_create_files,
	.setup		= avr32_perf_counter_setup,
	.shutdown	= avr32_perf_counter_shutdown,
	.start		= avr32_perf_counter_start,
	.stop		= avr32_perf_counter_stop,
	.cpu_type	= "avr32",
};

int __init oprofile_arch_init(struct oprofile_operations *ops)
{
	if (!(current_cpu_data.features & AVR32_FEATURE_PCTR))
		return -ENODEV;

	memcpy(ops, &avr32_perf_counter_ops,
			sizeof(struct oprofile_operations));

	ops->backtrace = avr32_backtrace;

	printk(KERN_INFO "oprofile: using AVR32 performance monitoring.\n");

	return 0;
}

void oprofile_arch_exit(void)
{

}