arch/arm/include/asm/arch_timer.h

   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