summaryrefslogtreecommitdiffstats
path: root/arch/sparc/kernel/pcr.c
blob: a24072a49270ea17e2cb5ee1a3da57eafd1e8352 (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
/* pcr.c: Generic sparc64 performance counter infrastructure.
 *
 * Copyright (C) 2009 David S. Miller (davem@davemloft.net)
 */
#include <linux/kernel.h>
#include <linux/export.h>
#include <linux/init.h>
#include <linux/irq.h>

#include <linux/irq_work.h>
#include <linux/ftrace.h>

#include <asm/pil.h>
#include <asm/pcr.h>
#include <asm/nmi.h>
#include <asm/spitfire.h>

/* This code is shared between various users of the performance
 * counters.  Users will be oprofile, pseudo-NMI watchdog, and the
 * perf_event support layer.
 */

#define PCR_SUN4U_ENABLE	(PCR_PIC_PRIV | PCR_STRACE | PCR_UTRACE)
#define PCR_N2_ENABLE		(PCR_PIC_PRIV | PCR_STRACE | PCR_UTRACE | \
				 PCR_N2_TOE_OV1 | \
				 (2 << PCR_N2_SL1_SHIFT) | \
				 (0xff << PCR_N2_MASK1_SHIFT))

u64 pcr_enable;
unsigned int picl_shift;

/* Performance counter interrupts run unmasked at PIL level 15.
 * Therefore we can't do things like wakeups and other work
 * that expects IRQ disabling to be adhered to in locking etc.
 *
 * Therefore in such situations we defer the work by signalling
 * a lower level cpu IRQ.
 */
void __irq_entry deferred_pcr_work_irq(int irq, struct pt_regs *regs)
{
	struct pt_regs *old_regs;

	clear_softint(1 << PIL_DEFERRED_PCR_WORK);

	old_regs = set_irq_regs(regs);
	irq_enter();
#ifdef CONFIG_IRQ_WORK
	irq_work_run();
#endif
	irq_exit();
	set_irq_regs(old_regs);
}

void arch_irq_work_raise(void)
{
	set_softint(1 << PIL_DEFERRED_PCR_WORK);
}

const struct pcr_ops *pcr_ops;
EXPORT_SYMBOL_GPL(pcr_ops);

static u64 direct_pcr_read(void)
{
	u64 val;

	read_pcr(val);
	return val;
}

static void direct_pcr_write(u64 val)
{
	write_pcr(val);
}

static const struct pcr_ops direct_pcr_ops = {
	.read	= direct_pcr_read,
	.write	= direct_pcr_write,
};

static void n2_pcr_write(u64 val)
{
	unsigned long ret;

	if (val & PCR_N2_HTRACE) {
		ret = sun4v_niagara2_setperf(HV_N2_PERF_SPARC_CTL, val);
		if (ret != HV_EOK)
			write_pcr(val);
	} else
		write_pcr(val);
}

static const struct pcr_ops n2_pcr_ops = {
	.read	= direct_pcr_read,
	.write	= n2_pcr_write,
};

static unsigned long perf_hsvc_group;
static unsigned long perf_hsvc_major;
static unsigned long perf_hsvc_minor;

static int __init register_perf_hsvc(void)
{
	if (tlb_type == hypervisor) {
		switch (sun4v_chip_type) {
		case SUN4V_CHIP_NIAGARA1:
			perf_hsvc_group = HV_GRP_NIAG_PERF;
			break;

		case SUN4V_CHIP_NIAGARA2:
			perf_hsvc_group = HV_GRP_N2_CPU;
			break;

		case SUN4V_CHIP_NIAGARA3:
			perf_hsvc_group = HV_GRP_KT_CPU;
			break;

		default:
			return -ENODEV;
		}


		perf_hsvc_major = 1;
		perf_hsvc_minor = 0;
		if (sun4v_hvapi_register(perf_hsvc_group,
					 perf_hsvc_major,
					 &perf_hsvc_minor)) {
			printk("perfmon: Could not register hvapi.\n");
			return -ENODEV;
		}
	}
	return 0;
}

static void __init unregister_perf_hsvc(void)
{
	if (tlb_type != hypervisor)
		return;
	sun4v_hvapi_unregister(perf_hsvc_group);
}

int __init pcr_arch_init(void)
{
	int err = register_perf_hsvc();

	if (err)
		return err;

	switch (tlb_type) {
	case hypervisor:
		pcr_ops = &n2_pcr_ops;
		pcr_enable = PCR_N2_ENABLE;
		picl_shift = 2;
		break;

	case cheetah:
	case cheetah_plus:
		pcr_ops = &direct_pcr_ops;
		pcr_enable = PCR_SUN4U_ENABLE;
		break;

	case spitfire:
		/* UltraSPARC-I/II and derivatives lack a profile
		 * counter overflow interrupt so we can't make use of
		 * their hardware currently.
		 */
		/* fallthrough */
	default:
		err = -ENODEV;
		goto out_unregister;
	}

	return nmi_init();

out_unregister:
	unregister_perf_hsvc();
	return err;
}
OpenPOWER on IntegriCloud