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 #define __USE_RTC() (IS_ENABLED(CONFIG_PPC_BOOK3S_601)) 43 44 #ifdef CONFIG_PPC64 45 46 /* For compatibility, get_tbl() is defined as get_tb() on ppc64 */ 47 #define get_tbl get_tb 48 49 #else 50 51 static inline unsigned long get_tbl(void) 52 { 53 return mftbl(); 54 } 55 56 static inline unsigned int get_tbu(void) 57 { 58 return mftbu(); 59 } 60 #endif /* !CONFIG_PPC64 */ 61 62 static inline unsigned int get_rtcl(void) 63 { 64 unsigned int rtcl; 65 66 asm volatile("mfrtcl %0" : "=r" (rtcl)); 67 return rtcl; 68 } 69 70 static inline u64 get_rtc(void) 71 { 72 unsigned int hi, lo, hi2; 73 74 do { 75 asm volatile("mfrtcu %0; mfrtcl %1; mfrtcu %2" 76 : "=r" (hi), "=r" (lo), "=r" (hi2)); 77 } while (hi2 != hi); 78 return (u64)hi * 1000000000 + lo; 79 } 80 81 static inline u64 get_vtb(void) 82 { 83 #ifdef CONFIG_PPC_BOOK3S_64 84 if (cpu_has_feature(CPU_FTR_ARCH_207S)) 85 return mfspr(SPRN_VTB); 86 #endif 87 return 0; 88 } 89 90 #ifdef CONFIG_PPC64 91 static inline u64 get_tb(void) 92 { 93 return mftb(); 94 } 95 #else /* CONFIG_PPC64 */ 96 static inline u64 get_tb(void) 97 { 98 unsigned int tbhi, tblo, tbhi2; 99 100 do { 101 tbhi = get_tbu(); 102 tblo = get_tbl(); 103 tbhi2 = get_tbu(); 104 } while (tbhi != tbhi2); 105 106 return ((u64)tbhi << 32) | tblo; 107 } 108 #endif /* !CONFIG_PPC64 */ 109 110 static inline u64 get_tb_or_rtc(void) 111 { 112 return __USE_RTC() ? get_rtc() : get_tb(); 113 } 114 115 static inline void set_tb(unsigned int upper, unsigned int lower) 116 { 117 mtspr(SPRN_TBWL, 0); 118 mtspr(SPRN_TBWU, upper); 119 mtspr(SPRN_TBWL, lower); 120 } 121 122 /* Accessor functions for the decrementer register. 123 * The 4xx doesn't even have a decrementer. I tried to use the 124 * generic timer interrupt code, which seems OK, with the 4xx PIT 125 * in auto-reload mode. The problem is PIT stops counting when it 126 * hits zero. If it would wrap, we could use it just like a decrementer. 127 */ 128 static inline u64 get_dec(void) 129 { 130 #if defined(CONFIG_40x) 131 return (mfspr(SPRN_PIT)); 132 #else 133 return (mfspr(SPRN_DEC)); 134 #endif 135 } 136 137 /* 138 * Note: Book E and 4xx processors differ from other PowerPC processors 139 * in when the decrementer generates its interrupt: on the 1 to 0 140 * transition for Book E/4xx, but on the 0 to -1 transition for others. 141 */ 142 static inline void set_dec(u64 val) 143 { 144 #if defined(CONFIG_40x) 145 mtspr(SPRN_PIT, (u32) val); 146 #else 147 #ifndef CONFIG_BOOKE 148 --val; 149 #endif 150 mtspr(SPRN_DEC, val); 151 #endif /* not 40x */ 152 } 153 154 static inline unsigned long tb_ticks_since(unsigned long tstamp) 155 { 156 if (__USE_RTC()) { 157 int delta = get_rtcl() - (unsigned int) tstamp; 158 return delta < 0 ? delta + 1000000000 : delta; 159 } 160 return get_tbl() - tstamp; 161 } 162 163 #define mulhwu(x,y) \ 164 ({unsigned z; asm ("mulhwu %0,%1,%2" : "=r" (z) : "r" (x), "r" (y)); z;}) 165 166 #ifdef CONFIG_PPC64 167 #define mulhdu(x,y) \ 168 ({unsigned long z; asm ("mulhdu %0,%1,%2" : "=r" (z) : "r" (x), "r" (y)); z;}) 169 #else 170 extern u64 mulhdu(u64, u64); 171 #endif 172 173 extern void div128_by_32(u64 dividend_high, u64 dividend_low, 174 unsigned divisor, struct div_result *dr); 175 176 extern void secondary_cpu_time_init(void); 177 extern void __init time_init(void); 178 179 DECLARE_PER_CPU(u64, decrementers_next_tb); 180 181 /* Convert timebase ticks to nanoseconds */ 182 unsigned long long tb_to_ns(unsigned long long tb_ticks); 183 184 /* SPLPAR */ 185 void accumulate_stolen_time(void); 186 187 #endif /* __KERNEL__ */ 188 #endif /* __POWERPC_TIME_H */ 189