summaryrefslogtreecommitdiffstats
path: root/arch/arm64/include/asm/arch_timer.h
blob: 9400596a0f3972a91a8858da56e9d7097e4b9319 (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
/*
 * arch/arm64/include/asm/arch_timer.h
 *
 * Copyright (C) 2012 ARM Ltd.
 * Author: Marc Zyngier <marc.zyngier@arm.com>
 *
 * 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.
 *
 * 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.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program.  If not, see <http://www.gnu.org/licenses/>.
 */
#ifndef __ASM_ARCH_TIMER_H
#define __ASM_ARCH_TIMER_H

#include <asm/barrier.h>

#include <linux/init.h>
#include <linux/types.h>

#include <clocksource/arm_arch_timer.h>

/*
 * These register accessors are marked inline so the compiler can
 * nicely work out which register we want, and chuck away the rest of
 * the code.
 */
static __always_inline
void arch_timer_reg_write_cp15(int access, enum arch_timer_reg reg, u32 val)
{
	if (access == ARCH_TIMER_PHYS_ACCESS) {
		switch (reg) {
		case ARCH_TIMER_REG_CTRL:
			asm volatile("msr cntp_ctl_el0,  %0" : : "r" (val));
			break;
		case ARCH_TIMER_REG_TVAL:
			asm volatile("msr cntp_tval_el0, %0" : : "r" (val));
			break;
		}
	} else if (access == ARCH_TIMER_VIRT_ACCESS) {
		switch (reg) {
		case ARCH_TIMER_REG_CTRL:
			asm volatile("msr cntv_ctl_el0,  %0" : : "r" (val));
			break;
		case ARCH_TIMER_REG_TVAL:
			asm volatile("msr cntv_tval_el0, %0" : : "r" (val));
			break;
		}
	}

	isb();
}

static __always_inline
u32 arch_timer_reg_read_cp15(int access, enum arch_timer_reg reg)
{
	u32 val;

	if (access == ARCH_TIMER_PHYS_ACCESS) {
		switch (reg) {
		case ARCH_TIMER_REG_CTRL:
			asm volatile("mrs %0,  cntp_ctl_el0" : "=r" (val));
			break;
		case ARCH_TIMER_REG_TVAL:
			asm volatile("mrs %0, cntp_tval_el0" : "=r" (val));
			break;
		}
	} else if (access == ARCH_TIMER_VIRT_ACCESS) {
		switch (reg) {
		case ARCH_TIMER_REG_CTRL:
			asm volatile("mrs %0,  cntv_ctl_el0" : "=r" (val));
			break;
		case ARCH_TIMER_REG_TVAL:
			asm volatile("mrs %0, cntv_tval_el0" : "=r" (val));
			break;
		}
	}

	return val;
}

static inline u32 arch_timer_get_cntfrq(void)
{
	u32 val;
	asm volatile("mrs %0,   cntfrq_el0" : "=r" (val));
	return val;
}

static inline u32 arch_timer_get_cntkctl(void)
{
	u32 cntkctl;
	asm volatile("mrs	%0, cntkctl_el1" : "=r" (cntkctl));
	return cntkctl;
}

static inline void arch_timer_set_cntkctl(u32 cntkctl)
{
	asm volatile("msr	cntkctl_el1, %0" : : "r" (cntkctl));
}

static inline void arch_counter_set_user_access(void)
{
	u32 cntkctl = arch_timer_get_cntkctl();

	/* Disable user access to the timers and the physical counter */
	/* Also disable virtual event stream */
	cntkctl &= ~(ARCH_TIMER_USR_PT_ACCESS_EN
			| ARCH_TIMER_USR_VT_ACCESS_EN
			| ARCH_TIMER_VIRT_EVT_EN
			| ARCH_TIMER_USR_PCT_ACCESS_EN);

	/* Enable user access to the virtual counter */
	cntkctl |= ARCH_TIMER_USR_VCT_ACCESS_EN;

	arch_timer_set_cntkctl(cntkctl);
}

static inline void arch_timer_evtstrm_enable(int divider)
{
	u32 cntkctl = arch_timer_get_cntkctl();
	cntkctl &= ~ARCH_TIMER_EVT_TRIGGER_MASK;
	/* Set the divider and enable virtual event stream */
	cntkctl |= (divider << ARCH_TIMER_EVT_TRIGGER_SHIFT)
			| ARCH_TIMER_VIRT_EVT_EN;
	arch_timer_set_cntkctl(cntkctl);
	elf_hwcap |= HWCAP_EVTSTRM;
#ifdef CONFIG_COMPAT
	compat_elf_hwcap |= COMPAT_HWCAP_EVTSTRM;
#endif
}

static inline u64 arch_counter_get_cntvct(void)
{
	u64 cval;

	isb();
	asm volatile("mrs %0, cntvct_el0" : "=r" (cval));

	return cval;
}

static inline int arch_timer_arch_init(void)
{
	return 0;
}

#endif