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1 #ifndef __ASMARM_ARCH_TIMER_H
2 #define __ASMARM_ARCH_TIMER_H
3 
4 #include <asm/barrier.h>
5 #include <asm/errno.h>
6 #include <linux/clocksource.h>
7 #include <linux/init.h>
8 #include <linux/types.h>
9 
10 #include <clocksource/arm_arch_timer.h>
11 
12 #ifdef CONFIG_ARM_ARCH_TIMER
13 int arch_timer_arch_init(void);
14 
15 /*
16  * These register accessors are marked inline so the compiler can
17  * nicely work out which register we want, and chuck away the rest of
18  * the code. At least it does so with a recent GCC (4.6.3).
19  */
arch_timer_reg_write(const int access,const int reg,u32 val)20 static inline void arch_timer_reg_write(const int access, const int reg, u32 val)
21 {
22 	if (access == ARCH_TIMER_PHYS_ACCESS) {
23 		switch (reg) {
24 		case ARCH_TIMER_REG_CTRL:
25 			asm volatile("mcr p15, 0, %0, c14, c2, 1" : : "r" (val));
26 			break;
27 		case ARCH_TIMER_REG_TVAL:
28 			asm volatile("mcr p15, 0, %0, c14, c2, 0" : : "r" (val));
29 			break;
30 		}
31 	}
32 
33 	if (access == ARCH_TIMER_VIRT_ACCESS) {
34 		switch (reg) {
35 		case ARCH_TIMER_REG_CTRL:
36 			asm volatile("mcr p15, 0, %0, c14, c3, 1" : : "r" (val));
37 			break;
38 		case ARCH_TIMER_REG_TVAL:
39 			asm volatile("mcr p15, 0, %0, c14, c3, 0" : : "r" (val));
40 			break;
41 		}
42 	}
43 
44 	isb();
45 }
46 
arch_timer_reg_read(const int access,const int reg)47 static inline u32 arch_timer_reg_read(const int access, const int reg)
48 {
49 	u32 val = 0;
50 
51 	if (access == ARCH_TIMER_PHYS_ACCESS) {
52 		switch (reg) {
53 		case ARCH_TIMER_REG_CTRL:
54 			asm volatile("mrc p15, 0, %0, c14, c2, 1" : "=r" (val));
55 			break;
56 		case ARCH_TIMER_REG_TVAL:
57 			asm volatile("mrc p15, 0, %0, c14, c2, 0" : "=r" (val));
58 			break;
59 		}
60 	}
61 
62 	if (access == ARCH_TIMER_VIRT_ACCESS) {
63 		switch (reg) {
64 		case ARCH_TIMER_REG_CTRL:
65 			asm volatile("mrc p15, 0, %0, c14, c3, 1" : "=r" (val));
66 			break;
67 		case ARCH_TIMER_REG_TVAL:
68 			asm volatile("mrc p15, 0, %0, c14, c3, 0" : "=r" (val));
69 			break;
70 		}
71 	}
72 
73 	return val;
74 }
75 
arch_timer_get_cntfrq(void)76 static inline u32 arch_timer_get_cntfrq(void)
77 {
78 	u32 val;
79 	asm volatile("mrc p15, 0, %0, c14, c0, 0" : "=r" (val));
80 	return val;
81 }
82 
arch_counter_get_cntvct(void)83 static inline u64 arch_counter_get_cntvct(void)
84 {
85 	u64 cval;
86 
87 	isb();
88 	asm volatile("mrrc p15, 1, %Q0, %R0, c14" : "=r" (cval));
89 	return cval;
90 }
91 
arch_timer_get_cntkctl(void)92 static inline u32 arch_timer_get_cntkctl(void)
93 {
94 	u32 cntkctl;
95 	asm volatile("mrc p15, 0, %0, c14, c1, 0" : "=r" (cntkctl));
96 	return cntkctl;
97 }
98 
arch_timer_set_cntkctl(u32 cntkctl)99 static inline void arch_timer_set_cntkctl(u32 cntkctl)
100 {
101 	asm volatile("mcr p15, 0, %0, c14, c1, 0" : : "r" (cntkctl));
102 }
103 
arch_counter_set_user_access(void)104 static inline void __cpuinit arch_counter_set_user_access(void)
105 {
106 	u32 cntkctl = arch_timer_get_cntkctl();
107 
108 	/* Disable user access to both physical/virtual counters/timers */
109 	/* Also disable virtual event stream */
110 	cntkctl &= ~(ARCH_TIMER_USR_PT_ACCESS_EN
111 			| ARCH_TIMER_USR_VT_ACCESS_EN
112 			| ARCH_TIMER_VIRT_EVT_EN
113 			| ARCH_TIMER_USR_VCT_ACCESS_EN
114 			| ARCH_TIMER_USR_PCT_ACCESS_EN);
115 	arch_timer_set_cntkctl(cntkctl);
116 }
117 
arch_timer_evtstrm_enable(int divider)118 static inline void arch_timer_evtstrm_enable(int divider)
119 {
120 	u32 cntkctl = arch_timer_get_cntkctl();
121 	cntkctl &= ~ARCH_TIMER_EVT_TRIGGER_MASK;
122 	/* Set the divider and enable virtual event stream */
123 	cntkctl |= (divider << ARCH_TIMER_EVT_TRIGGER_SHIFT)
124 			| ARCH_TIMER_VIRT_EVT_EN;
125 	arch_timer_set_cntkctl(cntkctl);
126 	elf_hwcap |= HWCAP_EVTSTRM;
127 }
128 
129 #endif
130 
131 #endif
132