1 /* SPDX-License-Identifier: GPL-2.0-or-later */ 2 /* 3 * Common time prototypes and such for all ppc machines. 4 * 5 * Written by Cort Dougan (cort@cs.nmt.edu) to merge 6 * Paul Mackerras' version and mine for PReP and Pmac. 7 */ 8 9 #ifndef __POWERPC_TIME_H 10 #define __POWERPC_TIME_H 11 12 #ifdef __KERNEL__ 13 #include <linux/types.h> 14 #include <linux/percpu.h> 15 16 #include <asm/processor.h> 17 #include <asm/cpu_has_feature.h> 18 19 /* time.c */ 20 extern unsigned long tb_ticks_per_jiffy; 21 extern unsigned long tb_ticks_per_usec; 22 extern unsigned long tb_ticks_per_sec; 23 extern struct clock_event_device decrementer_clockevent; 24 25 26 extern void generic_calibrate_decr(void); 27 28 /* Some sane defaults: 125 MHz timebase, 1GHz processor */ 29 extern unsigned long ppc_proc_freq; 30 #define DEFAULT_PROC_FREQ (DEFAULT_TB_FREQ * 8) 31 extern unsigned long ppc_tb_freq; 32 #define DEFAULT_TB_FREQ 125000000UL 33 34 extern bool tb_invalid; 35 36 struct div_result { 37 u64 result_high; 38 u64 result_low; 39 }; 40 41 /* Accessor functions for the timebase (RTC on 601) registers. */ 42 /* If one day CONFIG_POWER is added just define __USE_RTC as 1 */ 43 #define __USE_RTC() (IS_ENABLED(CONFIG_PPC_BOOK3S_601)) 44 45 #ifdef CONFIG_PPC64 46 47 /* For compatibility, get_tbl() is defined as get_tb() on ppc64 */ 48 #define get_tbl get_tb 49 50 #else 51 52 static inline unsigned long get_tbl(void) 53 { 54 return mftbl(); 55 } 56 57 static inline unsigned int get_tbu(void) 58 { 59 return mftbu(); 60 } 61 #endif /* !CONFIG_PPC64 */ 62 63 static inline unsigned int get_rtcl(void) 64 { 65 unsigned int rtcl; 66 67 asm volatile("mfrtcl %0" : "=r" (rtcl)); 68 return rtcl; 69 } 70 71 static inline u64 get_rtc(void) 72 { 73 unsigned int hi, lo, hi2; 74 75 do { 76 asm volatile("mfrtcu %0; mfrtcl %1; mfrtcu %2" 77 : "=r" (hi), "=r" (lo), "=r" (hi2)); 78 } while (hi2 != hi); 79 return (u64)hi * 1000000000 + lo; 80 } 81 82 static inline u64 get_vtb(void) 83 { 84 #ifdef CONFIG_PPC_BOOK3S_64 85 if (cpu_has_feature(CPU_FTR_ARCH_207S)) 86 return mfspr(SPRN_VTB); 87 #endif 88 return 0; 89 } 90 91 #ifdef CONFIG_PPC64 92 static inline u64 get_tb(void) 93 { 94 return mftb(); 95 } 96 #else /* CONFIG_PPC64 */ 97 static inline u64 get_tb(void) 98 { 99 unsigned int tbhi, tblo, tbhi2; 100 101 do { 102 tbhi = get_tbu(); 103 tblo = get_tbl(); 104 tbhi2 = get_tbu(); 105 } while (tbhi != tbhi2); 106 107 return ((u64)tbhi << 32) | tblo; 108 } 109 #endif /* !CONFIG_PPC64 */ 110 111 static inline u64 get_tb_or_rtc(void) 112 { 113 return __USE_RTC() ? get_rtc() : get_tb(); 114 } 115 116 static inline void set_tb(unsigned int upper, unsigned int lower) 117 { 118 mtspr(SPRN_TBWL, 0); 119 mtspr(SPRN_TBWU, upper); 120 mtspr(SPRN_TBWL, lower); 121 } 122 123 /* Accessor functions for the decrementer register. 124 * The 4xx doesn't even have a decrementer. I tried to use the 125 * generic timer interrupt code, which seems OK, with the 4xx PIT 126 * in auto-reload mode. The problem is PIT stops counting when it 127 * hits zero. If it would wrap, we could use it just like a decrementer. 128 */ 129 static inline u64 get_dec(void) 130 { 131 #if defined(CONFIG_40x) 132 return (mfspr(SPRN_PIT)); 133 #else 134 return (mfspr(SPRN_DEC)); 135 #endif 136 } 137 138 /* 139 * Note: Book E and 4xx processors differ from other PowerPC processors 140 * in when the decrementer generates its interrupt: on the 1 to 0 141 * transition for Book E/4xx, but on the 0 to -1 transition for others. 142 */ 143 static inline void set_dec(u64 val) 144 { 145 #if defined(CONFIG_40x) 146 mtspr(SPRN_PIT, (u32) val); 147 #else 148 #ifndef CONFIG_BOOKE 149 --val; 150 #endif 151 mtspr(SPRN_DEC, val); 152 #endif /* not 40x */ 153 } 154 155 static inline unsigned long tb_ticks_since(unsigned long tstamp) 156 { 157 if (__USE_RTC()) { 158 int delta = get_rtcl() - (unsigned int) tstamp; 159 return delta < 0 ? delta + 1000000000 : delta; 160 } 161 return get_tbl() - tstamp; 162 } 163 164 #define mulhwu(x,y) \ 165 ({unsigned z; asm ("mulhwu %0,%1,%2" : "=r" (z) : "r" (x), "r" (y)); z;}) 166 167 #ifdef CONFIG_PPC64 168 #define mulhdu(x,y) \ 169 ({unsigned long z; asm ("mulhdu %0,%1,%2" : "=r" (z) : "r" (x), "r" (y)); z;}) 170 #else 171 extern u64 mulhdu(u64, u64); 172 #endif 173 174 extern void div128_by_32(u64 dividend_high, u64 dividend_low, 175 unsigned divisor, struct div_result *dr); 176 177 extern void secondary_cpu_time_init(void); 178 extern void __init time_init(void); 179 180 DECLARE_PER_CPU(u64, decrementers_next_tb); 181 182 /* Convert timebase ticks to nanoseconds */ 183 unsigned long long tb_to_ns(unsigned long long tb_ticks); 184 185 /* SPLPAR */ 186 void accumulate_stolen_time(void); 187 188 #endif /* __KERNEL__ */ 189 #endif /* __POWERPC_TIME_H */ 190