xref: /linux/arch/arm/include/asm/arch_timer.h (revision 4775bc63f880001ee4fbd6456b12ab04674149e3)
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 		default:
38 			BUILD_BUG();
39 		}
40 	} else if (access == ARCH_TIMER_VIRT_ACCESS) {
41 		switch (reg) {
42 		case ARCH_TIMER_REG_CTRL:
43 			asm volatile("mcr p15, 0, %0, c14, c3, 1" : : "r" (val));
44 			break;
45 		case ARCH_TIMER_REG_TVAL:
46 			asm volatile("mcr p15, 0, %0, c14, c3, 0" : : "r" (val));
47 			break;
48 		default:
49 			BUILD_BUG();
50 		}
51 	} else {
52 		BUILD_BUG();
53 	}
54 
55 	isb();
56 }
57 
58 static __always_inline
59 u32 arch_timer_reg_read_cp15(int access, enum arch_timer_reg reg)
60 {
61 	u32 val = 0;
62 
63 	if (access == ARCH_TIMER_PHYS_ACCESS) {
64 		switch (reg) {
65 		case ARCH_TIMER_REG_CTRL:
66 			asm volatile("mrc p15, 0, %0, c14, c2, 1" : "=r" (val));
67 			break;
68 		case ARCH_TIMER_REG_TVAL:
69 			asm volatile("mrc p15, 0, %0, c14, c2, 0" : "=r" (val));
70 			break;
71 		default:
72 			BUILD_BUG();
73 		}
74 	} else if (access == ARCH_TIMER_VIRT_ACCESS) {
75 		switch (reg) {
76 		case ARCH_TIMER_REG_CTRL:
77 			asm volatile("mrc p15, 0, %0, c14, c3, 1" : "=r" (val));
78 			break;
79 		case ARCH_TIMER_REG_TVAL:
80 			asm volatile("mrc p15, 0, %0, c14, c3, 0" : "=r" (val));
81 			break;
82 		default:
83 			BUILD_BUG();
84 		}
85 	} else {
86 		BUILD_BUG();
87 	}
88 
89 	return val;
90 }
91 
92 static inline u32 arch_timer_get_cntfrq(void)
93 {
94 	u32 val;
95 	asm volatile("mrc p15, 0, %0, c14, c0, 0" : "=r" (val));
96 	return val;
97 }
98 
99 static inline u64 __arch_counter_get_cntpct(void)
100 {
101 	u64 cval;
102 
103 	isb();
104 	asm volatile("mrrc p15, 0, %Q0, %R0, c14" : "=r" (cval));
105 	return cval;
106 }
107 
108 static inline u64 __arch_counter_get_cntpct_stable(void)
109 {
110 	return __arch_counter_get_cntpct();
111 }
112 
113 static inline u64 __arch_counter_get_cntvct(void)
114 {
115 	u64 cval;
116 
117 	isb();
118 	asm volatile("mrrc p15, 1, %Q0, %R0, c14" : "=r" (cval));
119 	return cval;
120 }
121 
122 static inline u64 __arch_counter_get_cntvct_stable(void)
123 {
124 	return __arch_counter_get_cntvct();
125 }
126 
127 static inline u32 arch_timer_get_cntkctl(void)
128 {
129 	u32 cntkctl;
130 	asm volatile("mrc p15, 0, %0, c14, c1, 0" : "=r" (cntkctl));
131 	return cntkctl;
132 }
133 
134 static inline void arch_timer_set_cntkctl(u32 cntkctl)
135 {
136 	asm volatile("mcr p15, 0, %0, c14, c1, 0" : : "r" (cntkctl));
137 	isb();
138 }
139 
140 static inline void arch_timer_set_evtstrm_feature(void)
141 {
142 	elf_hwcap |= HWCAP_EVTSTRM;
143 }
144 
145 static inline bool arch_timer_have_evtstrm_feature(void)
146 {
147 	return elf_hwcap & HWCAP_EVTSTRM;
148 }
149 #endif
150 
151 #endif
152