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 unsigned long tb_ticks_per_jiffy; 22 extern unsigned long tb_ticks_per_usec; 23 extern unsigned long tb_ticks_per_sec; 24 extern struct clock_event_device decrementer_clockevent; 25 26 27 extern void generic_calibrate_decr(void); 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 static inline u64 get_vtb(void) 43 { 44 if (cpu_has_feature(CPU_FTR_ARCH_207S)) 45 return mfspr(SPRN_VTB); 46 47 return 0; 48 } 49 50 /* Accessor functions for the decrementer register. 51 * The 4xx doesn't even have a decrementer. I tried to use the 52 * generic timer interrupt code, which seems OK, with the 4xx PIT 53 * in auto-reload mode. The problem is PIT stops counting when it 54 * hits zero. If it would wrap, we could use it just like a decrementer. 55 */ 56 static inline u64 get_dec(void) 57 { 58 if (IS_ENABLED(CONFIG_40x)) 59 return mfspr(SPRN_PIT); 60 61 return mfspr(SPRN_DEC); 62 } 63 64 /* 65 * Note: Book E and 4xx processors differ from other PowerPC processors 66 * in when the decrementer generates its interrupt: on the 1 to 0 67 * transition for Book E/4xx, but on the 0 to -1 transition for others. 68 */ 69 static inline void set_dec(u64 val) 70 { 71 if (IS_ENABLED(CONFIG_40x)) 72 mtspr(SPRN_PIT, (u32)val); 73 else if (IS_ENABLED(CONFIG_BOOKE)) 74 mtspr(SPRN_DEC, val); 75 else 76 mtspr(SPRN_DEC, val - 1); 77 } 78 79 static inline unsigned long tb_ticks_since(unsigned long tstamp) 80 { 81 return mftb() - tstamp; 82 } 83 84 #define mulhwu(x,y) \ 85 ({unsigned z; asm ("mulhwu %0,%1,%2" : "=r" (z) : "r" (x), "r" (y)); z;}) 86 87 #ifdef CONFIG_PPC64 88 #define mulhdu(x,y) \ 89 ({unsigned long z; asm ("mulhdu %0,%1,%2" : "=r" (z) : "r" (x), "r" (y)); z;}) 90 #else 91 extern u64 mulhdu(u64, u64); 92 #endif 93 94 extern void div128_by_32(u64 dividend_high, u64 dividend_low, 95 unsigned divisor, struct div_result *dr); 96 97 extern void secondary_cpu_time_init(void); 98 extern void __init time_init(void); 99 100 DECLARE_PER_CPU(u64, decrementers_next_tb); 101 102 /* Convert timebase ticks to nanoseconds */ 103 unsigned long long tb_to_ns(unsigned long long tb_ticks); 104 105 void timer_broadcast_interrupt(void); 106 107 /* SPLPAR */ 108 void accumulate_stolen_time(void); 109 110 #endif /* __KERNEL__ */ 111 #endif /* __POWERPC_TIME_H */ 112