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 /* For compatibility, get_tbl() is defined as get_tb() on ppc64 */ 42 static inline unsigned long get_tbl(void) 43 { 44 return mftb(); 45 } 46 47 static inline u64 get_vtb(void) 48 { 49 #ifdef CONFIG_PPC_BOOK3S_64 50 if (cpu_has_feature(CPU_FTR_ARCH_207S)) 51 return mfspr(SPRN_VTB); 52 #endif 53 return 0; 54 } 55 56 static inline u64 get_tb(void) 57 { 58 unsigned int tbhi, tblo, tbhi2; 59 60 if (IS_ENABLED(CONFIG_PPC64)) 61 return mftb(); 62 63 do { 64 tbhi = mftbu(); 65 tblo = mftb(); 66 tbhi2 = mftbu(); 67 } while (tbhi != tbhi2); 68 69 return ((u64)tbhi << 32) | tblo; 70 } 71 72 static inline void set_tb(unsigned int upper, unsigned int lower) 73 { 74 mtspr(SPRN_TBWL, 0); 75 mtspr(SPRN_TBWU, upper); 76 mtspr(SPRN_TBWL, lower); 77 } 78 79 /* Accessor functions for the decrementer register. 80 * The 4xx doesn't even have a decrementer. I tried to use the 81 * generic timer interrupt code, which seems OK, with the 4xx PIT 82 * in auto-reload mode. The problem is PIT stops counting when it 83 * hits zero. If it would wrap, we could use it just like a decrementer. 84 */ 85 static inline u64 get_dec(void) 86 { 87 if (IS_ENABLED(CONFIG_40x)) 88 return mfspr(SPRN_PIT); 89 90 return mfspr(SPRN_DEC); 91 } 92 93 /* 94 * Note: Book E and 4xx processors differ from other PowerPC processors 95 * in when the decrementer generates its interrupt: on the 1 to 0 96 * transition for Book E/4xx, but on the 0 to -1 transition for others. 97 */ 98 static inline void set_dec(u64 val) 99 { 100 if (IS_ENABLED(CONFIG_40x)) 101 mtspr(SPRN_PIT, (u32)val); 102 else if (IS_ENABLED(CONFIG_BOOKE)) 103 mtspr(SPRN_DEC, val); 104 else 105 mtspr(SPRN_DEC, val - 1); 106 } 107 108 static inline unsigned long tb_ticks_since(unsigned long tstamp) 109 { 110 return mftb() - tstamp; 111 } 112 113 #define mulhwu(x,y) \ 114 ({unsigned z; asm ("mulhwu %0,%1,%2" : "=r" (z) : "r" (x), "r" (y)); z;}) 115 116 #ifdef CONFIG_PPC64 117 #define mulhdu(x,y) \ 118 ({unsigned long z; asm ("mulhdu %0,%1,%2" : "=r" (z) : "r" (x), "r" (y)); z;}) 119 #else 120 extern u64 mulhdu(u64, u64); 121 #endif 122 123 extern void div128_by_32(u64 dividend_high, u64 dividend_low, 124 unsigned divisor, struct div_result *dr); 125 126 extern void secondary_cpu_time_init(void); 127 extern void __init time_init(void); 128 129 DECLARE_PER_CPU(u64, decrementers_next_tb); 130 131 /* Convert timebase ticks to nanoseconds */ 132 unsigned long long tb_to_ns(unsigned long long tb_ticks); 133 134 /* SPLPAR */ 135 void accumulate_stolen_time(void); 136 137 #endif /* __KERNEL__ */ 138 #endif /* __POWERPC_TIME_H */ 139