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 extern void hdec_interrupt(struct pt_regs *regs); 28 29 /* Some sane defaults: 125 MHz timebase, 1GHz processor */ 30 extern unsigned long ppc_proc_freq; 31 #define DEFAULT_PROC_FREQ (DEFAULT_TB_FREQ * 8) 32 extern unsigned long ppc_tb_freq; 33 #define DEFAULT_TB_FREQ 125000000UL 34 35 extern bool tb_invalid; 36 37 struct div_result { 38 u64 result_high; 39 u64 result_low; 40 }; 41 42 /* Accessor functions for the timebase (RTC on 601) registers. */ 43 /* If one day CONFIG_POWER is added just define __USE_RTC as 1 */ 44 #define __USE_RTC() (IS_ENABLED(CONFIG_PPC_BOOK3S_601)) 45 46 #ifdef CONFIG_PPC64 47 48 /* For compatibility, get_tbl() is defined as get_tb() on ppc64 */ 49 #define get_tbl get_tb 50 51 #else 52 53 static inline unsigned long get_tbl(void) 54 { 55 #if defined(CONFIG_403GCX) 56 unsigned long tbl; 57 asm volatile("mfspr %0, 0x3dd" : "=r" (tbl)); 58 return tbl; 59 #else 60 return mftbl(); 61 #endif 62 } 63 64 static inline unsigned int get_tbu(void) 65 { 66 #ifdef CONFIG_403GCX 67 unsigned int tbu; 68 asm volatile("mfspr %0, 0x3dc" : "=r" (tbu)); 69 return tbu; 70 #else 71 return mftbu(); 72 #endif 73 } 74 #endif /* !CONFIG_PPC64 */ 75 76 static inline unsigned int get_rtcl(void) 77 { 78 unsigned int rtcl; 79 80 asm volatile("mfrtcl %0" : "=r" (rtcl)); 81 return rtcl; 82 } 83 84 static inline u64 get_rtc(void) 85 { 86 unsigned int hi, lo, hi2; 87 88 do { 89 asm volatile("mfrtcu %0; mfrtcl %1; mfrtcu %2" 90 : "=r" (hi), "=r" (lo), "=r" (hi2)); 91 } while (hi2 != hi); 92 return (u64)hi * 1000000000 + lo; 93 } 94 95 static inline u64 get_vtb(void) 96 { 97 #ifdef CONFIG_PPC_BOOK3S_64 98 if (cpu_has_feature(CPU_FTR_ARCH_207S)) 99 return mfspr(SPRN_VTB); 100 #endif 101 return 0; 102 } 103 104 #ifdef CONFIG_PPC64 105 static inline u64 get_tb(void) 106 { 107 return mftb(); 108 } 109 #else /* CONFIG_PPC64 */ 110 static inline u64 get_tb(void) 111 { 112 unsigned int tbhi, tblo, tbhi2; 113 114 do { 115 tbhi = get_tbu(); 116 tblo = get_tbl(); 117 tbhi2 = get_tbu(); 118 } while (tbhi != tbhi2); 119 120 return ((u64)tbhi << 32) | tblo; 121 } 122 #endif /* !CONFIG_PPC64 */ 123 124 static inline u64 get_tb_or_rtc(void) 125 { 126 return __USE_RTC() ? get_rtc() : get_tb(); 127 } 128 129 static inline void set_tb(unsigned int upper, unsigned int lower) 130 { 131 mtspr(SPRN_TBWL, 0); 132 mtspr(SPRN_TBWU, upper); 133 mtspr(SPRN_TBWL, lower); 134 } 135 136 /* Accessor functions for the decrementer register. 137 * The 4xx doesn't even have a decrementer. I tried to use the 138 * generic timer interrupt code, which seems OK, with the 4xx PIT 139 * in auto-reload mode. The problem is PIT stops counting when it 140 * hits zero. If it would wrap, we could use it just like a decrementer. 141 */ 142 static inline u64 get_dec(void) 143 { 144 #if defined(CONFIG_40x) 145 return (mfspr(SPRN_PIT)); 146 #else 147 return (mfspr(SPRN_DEC)); 148 #endif 149 } 150 151 /* 152 * Note: Book E and 4xx processors differ from other PowerPC processors 153 * in when the decrementer generates its interrupt: on the 1 to 0 154 * transition for Book E/4xx, but on the 0 to -1 transition for others. 155 */ 156 static inline void set_dec(u64 val) 157 { 158 #if defined(CONFIG_40x) 159 mtspr(SPRN_PIT, (u32) val); 160 #else 161 #ifndef CONFIG_BOOKE 162 --val; 163 #endif 164 mtspr(SPRN_DEC, val); 165 #endif /* not 40x */ 166 } 167 168 static inline unsigned long tb_ticks_since(unsigned long tstamp) 169 { 170 if (__USE_RTC()) { 171 int delta = get_rtcl() - (unsigned int) tstamp; 172 return delta < 0 ? delta + 1000000000 : delta; 173 } 174 return get_tbl() - tstamp; 175 } 176 177 #define mulhwu(x,y) \ 178 ({unsigned z; asm ("mulhwu %0,%1,%2" : "=r" (z) : "r" (x), "r" (y)); z;}) 179 180 #ifdef CONFIG_PPC64 181 #define mulhdu(x,y) \ 182 ({unsigned long z; asm ("mulhdu %0,%1,%2" : "=r" (z) : "r" (x), "r" (y)); z;}) 183 #else 184 extern u64 mulhdu(u64, u64); 185 #endif 186 187 extern void div128_by_32(u64 dividend_high, u64 dividend_low, 188 unsigned divisor, struct div_result *dr); 189 190 extern void secondary_cpu_time_init(void); 191 extern void __init time_init(void); 192 193 DECLARE_PER_CPU(u64, decrementers_next_tb); 194 195 /* Convert timebase ticks to nanoseconds */ 196 unsigned long long tb_to_ns(unsigned long long tb_ticks); 197 198 #endif /* __KERNEL__ */ 199 #endif /* __POWERPC_TIME_H */ 200