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 */ 20 static __always_inline 21 void arch_timer_reg_write_cp15(int access, enum arch_timer_reg reg, u32 val) 22 { 23 if (access == ARCH_TIMER_PHYS_ACCESS) { 24 switch (reg) { 25 case ARCH_TIMER_REG_CTRL: 26 asm volatile("mcr p15, 0, %0, c14, c2, 1" : : "r" (val)); 27 break; 28 case ARCH_TIMER_REG_TVAL: 29 asm volatile("mcr p15, 0, %0, c14, c2, 0" : : "r" (val)); 30 break; 31 } 32 } else if (access == ARCH_TIMER_VIRT_ACCESS) { 33 switch (reg) { 34 case ARCH_TIMER_REG_CTRL: 35 asm volatile("mcr p15, 0, %0, c14, c3, 1" : : "r" (val)); 36 break; 37 case ARCH_TIMER_REG_TVAL: 38 asm volatile("mcr p15, 0, %0, c14, c3, 0" : : "r" (val)); 39 break; 40 } 41 } 42 43 isb(); 44 } 45 46 static __always_inline 47 u32 arch_timer_reg_read_cp15(int access, enum arch_timer_reg 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 } else if (access == ARCH_TIMER_VIRT_ACCESS) { 61 switch (reg) { 62 case ARCH_TIMER_REG_CTRL: 63 asm volatile("mrc p15, 0, %0, c14, c3, 1" : "=r" (val)); 64 break; 65 case ARCH_TIMER_REG_TVAL: 66 asm volatile("mrc p15, 0, %0, c14, c3, 0" : "=r" (val)); 67 break; 68 } 69 } 70 71 return val; 72 } 73 74 static inline u32 arch_timer_get_cntfrq(void) 75 { 76 u32 val; 77 asm volatile("mrc p15, 0, %0, c14, c0, 0" : "=r" (val)); 78 return val; 79 } 80 81 static inline u64 arch_counter_get_cntvct(void) 82 { 83 u64 cval; 84 85 isb(); 86 asm volatile("mrrc p15, 1, %Q0, %R0, c14" : "=r" (cval)); 87 return cval; 88 } 89 90 static inline u32 arch_timer_get_cntkctl(void) 91 { 92 u32 cntkctl; 93 asm volatile("mrc p15, 0, %0, c14, c1, 0" : "=r" (cntkctl)); 94 return cntkctl; 95 } 96 97 static inline void arch_timer_set_cntkctl(u32 cntkctl) 98 { 99 asm volatile("mcr p15, 0, %0, c14, c1, 0" : : "r" (cntkctl)); 100 } 101 102 static inline void arch_counter_set_user_access(void) 103 { 104 u32 cntkctl = arch_timer_get_cntkctl(); 105 106 /* Disable user access to both physical/virtual counters/timers */ 107 /* Also disable virtual event stream */ 108 cntkctl &= ~(ARCH_TIMER_USR_PT_ACCESS_EN 109 | ARCH_TIMER_USR_VT_ACCESS_EN 110 | ARCH_TIMER_VIRT_EVT_EN 111 | ARCH_TIMER_USR_VCT_ACCESS_EN 112 | ARCH_TIMER_USR_PCT_ACCESS_EN); 113 arch_timer_set_cntkctl(cntkctl); 114 } 115 116 static inline void arch_timer_evtstrm_enable(int divider) 117 { 118 u32 cntkctl = arch_timer_get_cntkctl(); 119 cntkctl &= ~ARCH_TIMER_EVT_TRIGGER_MASK; 120 /* Set the divider and enable virtual event stream */ 121 cntkctl |= (divider << ARCH_TIMER_EVT_TRIGGER_SHIFT) 122 | ARCH_TIMER_VIRT_EVT_EN; 123 arch_timer_set_cntkctl(cntkctl); 124 elf_hwcap |= HWCAP_EVTSTRM; 125 } 126 127 #endif 128 129 #endif 130