xref: /openbmc/linux/arch/arm/include/asm/arch_timer.h (revision e15a5365)
1 /* SPDX-License-Identifier: GPL-2.0 */
2 #ifndef __ASMARM_ARCH_TIMER_H
3 #define __ASMARM_ARCH_TIMER_H
4 
5 #include <asm/barrier.h>
6 #include <asm/errno.h>
7 #include <asm/hwcap.h>
8 #include <linux/clocksource.h>
9 #include <linux/init.h>
10 #include <linux/types.h>
11 
12 #include <clocksource/arm_arch_timer.h>
13 
14 #ifdef CONFIG_ARM_ARCH_TIMER
15 /* 32bit ARM doesn't know anything about timer errata... */
16 #define has_erratum_handler(h)		(false)
17 #define erratum_handler(h)		(arch_timer_##h)
18 
19 int arch_timer_arch_init(void);
20 
21 /*
22  * These register accessors are marked inline so the compiler can
23  * nicely work out which register we want, and chuck away the rest of
24  * the code. At least it does so with a recent GCC (4.6.3).
25  */
26 static __always_inline
27 void arch_timer_reg_write_cp15(int access, enum arch_timer_reg reg, u32 val)
28 {
29 	if (access == ARCH_TIMER_PHYS_ACCESS) {
30 		switch (reg) {
31 		case ARCH_TIMER_REG_CTRL:
32 			asm volatile("mcr p15, 0, %0, c14, c2, 1" : : "r" (val));
33 			break;
34 		case ARCH_TIMER_REG_TVAL:
35 			asm volatile("mcr p15, 0, %0, c14, c2, 0" : : "r" (val));
36 			break;
37 		}
38 	} else if (access == ARCH_TIMER_VIRT_ACCESS) {
39 		switch (reg) {
40 		case ARCH_TIMER_REG_CTRL:
41 			asm volatile("mcr p15, 0, %0, c14, c3, 1" : : "r" (val));
42 			break;
43 		case ARCH_TIMER_REG_TVAL:
44 			asm volatile("mcr p15, 0, %0, c14, c3, 0" : : "r" (val));
45 			break;
46 		}
47 	}
48 
49 	isb();
50 }
51 
52 static __always_inline
53 u32 arch_timer_reg_read_cp15(int access, enum arch_timer_reg reg)
54 {
55 	u32 val = 0;
56 
57 	if (access == ARCH_TIMER_PHYS_ACCESS) {
58 		switch (reg) {
59 		case ARCH_TIMER_REG_CTRL:
60 			asm volatile("mrc p15, 0, %0, c14, c2, 1" : "=r" (val));
61 			break;
62 		case ARCH_TIMER_REG_TVAL:
63 			asm volatile("mrc p15, 0, %0, c14, c2, 0" : "=r" (val));
64 			break;
65 		}
66 	} else if (access == ARCH_TIMER_VIRT_ACCESS) {
67 		switch (reg) {
68 		case ARCH_TIMER_REG_CTRL:
69 			asm volatile("mrc p15, 0, %0, c14, c3, 1" : "=r" (val));
70 			break;
71 		case ARCH_TIMER_REG_TVAL:
72 			asm volatile("mrc p15, 0, %0, c14, c3, 0" : "=r" (val));
73 			break;
74 		}
75 	}
76 
77 	return val;
78 }
79 
80 static inline u32 arch_timer_get_cntfrq(void)
81 {
82 	u32 val;
83 	asm volatile("mrc p15, 0, %0, c14, c0, 0" : "=r" (val));
84 	return val;
85 }
86 
87 static inline u64 __arch_counter_get_cntpct(void)
88 {
89 	u64 cval;
90 
91 	isb();
92 	asm volatile("mrrc p15, 0, %Q0, %R0, c14" : "=r" (cval));
93 	return cval;
94 }
95 
96 static inline u64 __arch_counter_get_cntpct_stable(void)
97 {
98 	return __arch_counter_get_cntpct();
99 }
100 
101 static inline u64 __arch_counter_get_cntvct(void)
102 {
103 	u64 cval;
104 
105 	isb();
106 	asm volatile("mrrc p15, 1, %Q0, %R0, c14" : "=r" (cval));
107 	return cval;
108 }
109 
110 static inline u64 __arch_counter_get_cntvct_stable(void)
111 {
112 	return __arch_counter_get_cntvct();
113 }
114 
115 static inline u32 arch_timer_get_cntkctl(void)
116 {
117 	u32 cntkctl;
118 	asm volatile("mrc p15, 0, %0, c14, c1, 0" : "=r" (cntkctl));
119 	return cntkctl;
120 }
121 
122 static inline void arch_timer_set_cntkctl(u32 cntkctl)
123 {
124 	asm volatile("mcr p15, 0, %0, c14, c1, 0" : : "r" (cntkctl));
125 	isb();
126 }
127 
128 static inline void arch_timer_set_evtstrm_feature(void)
129 {
130 	elf_hwcap |= HWCAP_EVTSTRM;
131 }
132 
133 static inline bool arch_timer_have_evtstrm_feature(void)
134 {
135 	return elf_hwcap & HWCAP_EVTSTRM;
136 }
137 #endif
138 
139 #endif
140