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 #include <asm/vdso/timebase.h> 19 20 /* time.c */ 21 extern u64 decrementer_max; 22 23 extern unsigned long tb_ticks_per_jiffy; 24 extern unsigned long tb_ticks_per_usec; 25 extern unsigned long tb_ticks_per_sec; 26 extern struct clock_event_device decrementer_clockevent; 27 extern u64 decrementer_max; 28 29 30 extern void generic_calibrate_decr(void); 31 32 /* Some sane defaults: 125 MHz timebase, 1GHz processor */ 33 extern unsigned long ppc_proc_freq; 34 #define DEFAULT_PROC_FREQ (DEFAULT_TB_FREQ * 8) 35 extern unsigned long ppc_tb_freq; 36 #define DEFAULT_TB_FREQ 125000000UL 37 38 extern bool tb_invalid; 39 40 struct div_result { 41 u64 result_high; 42 u64 result_low; 43 }; 44 45 static inline u64 get_vtb(void) 46 { 47 if (cpu_has_feature(CPU_FTR_ARCH_207S)) 48 return mfspr(SPRN_VTB); 49 50 return 0; 51 } 52 53 /* Accessor functions for the decrementer register. 54 * The 4xx doesn't even have a decrementer. I tried to use the 55 * generic timer interrupt code, which seems OK, with the 4xx PIT 56 * in auto-reload mode. The problem is PIT stops counting when it 57 * hits zero. If it would wrap, we could use it just like a decrementer. 58 */ 59 static inline u64 get_dec(void) 60 { 61 if (IS_ENABLED(CONFIG_40x)) 62 return mfspr(SPRN_PIT); 63 64 return mfspr(SPRN_DEC); 65 } 66 67 /* 68 * Note: Book E and 4xx processors differ from other PowerPC processors 69 * in when the decrementer generates its interrupt: on the 1 to 0 70 * transition for Book E/4xx, but on the 0 to -1 transition for others. 71 */ 72 static inline void set_dec(u64 val) 73 { 74 if (IS_ENABLED(CONFIG_40x)) 75 mtspr(SPRN_PIT, (u32)val); 76 else if (IS_ENABLED(CONFIG_BOOKE)) 77 mtspr(SPRN_DEC, val); 78 else 79 mtspr(SPRN_DEC, val - 1); 80 } 81 82 static inline unsigned long tb_ticks_since(unsigned long tstamp) 83 { 84 return mftb() - tstamp; 85 } 86 87 #define mulhwu(x,y) \ 88 ({unsigned z; asm ("mulhwu %0,%1,%2" : "=r" (z) : "r" (x), "r" (y)); z;}) 89 90 #ifdef CONFIG_PPC64 91 #define mulhdu(x,y) \ 92 ({unsigned long z; asm ("mulhdu %0,%1,%2" : "=r" (z) : "r" (x), "r" (y)); z;}) 93 #else 94 extern u64 mulhdu(u64, u64); 95 #endif 96 97 extern void div128_by_32(u64 dividend_high, u64 dividend_low, 98 unsigned divisor, struct div_result *dr); 99 100 extern void secondary_cpu_time_init(void); 101 extern void __init time_init(void); 102 103 DECLARE_PER_CPU(u64, decrementers_next_tb); 104 105 static inline u64 timer_get_next_tb(void) 106 { 107 return __this_cpu_read(decrementers_next_tb); 108 } 109 110 #ifdef CONFIG_KVM_BOOK3S_HV_POSSIBLE 111 void timer_rearm_host_dec(u64 now); 112 #endif 113 114 /* Convert timebase ticks to nanoseconds */ 115 unsigned long long tb_to_ns(unsigned long long tb_ticks); 116 117 void timer_broadcast_interrupt(void); 118 119 /* SPLPAR */ 120 void accumulate_stolen_time(void); 121 122 #endif /* __KERNEL__ */ 123 #endif /* __POWERPC_TIME_H */ 124