1 /* SPDX-License-Identifier: GPL-2.0-or-later */
3 * Common time prototypes and such for all ppc machines.
5 * Written by Cort Dougan (cort@cs.nmt.edu) to merge
6 * Paul Mackerras' version and mine for PReP and Pmac.
9 #ifndef __POWERPC_TIME_H
10 #define __POWERPC_TIME_H
13 #include <linux/types.h>
14 #include <linux/percpu.h>
16 #include <asm/processor.h>
17 #include <asm/cpu_has_feature.h>
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;
26 extern void generic_calibrate_decr(void);
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
34 extern bool tb_invalid;
41 /* Accessor functions for the timebase (RTC on 601) registers. */
42 /* If one day CONFIG_POWER is added just define __USE_RTC as 1 */
43 #define __USE_RTC() (IS_ENABLED(CONFIG_PPC_BOOK3S_601))
47 /* For compatibility, get_tbl() is defined as get_tb() on ppc64 */
48 #define get_tbl get_tb
52 static inline unsigned long get_tbl(void)
57 static inline unsigned int get_tbu(void)
61 #endif /* !CONFIG_PPC64 */
63 static inline unsigned int get_rtcl(void)
67 asm volatile("mfrtcl %0" : "=r" (rtcl));
71 static inline u64 get_rtc(void)
73 unsigned int hi, lo, hi2;
76 asm volatile("mfrtcu %0; mfrtcl %1; mfrtcu %2"
77 : "=r" (hi), "=r" (lo), "=r" (hi2));
79 return (u64)hi * 1000000000 + lo;
82 static inline u64 get_vtb(void)
84 #ifdef CONFIG_PPC_BOOK3S_64
85 if (cpu_has_feature(CPU_FTR_ARCH_207S))
86 return mfspr(SPRN_VTB);
92 static inline u64 get_tb(void)
96 #else /* CONFIG_PPC64 */
97 static inline u64 get_tb(void)
99 unsigned int tbhi, tblo, tbhi2;
105 } while (tbhi != tbhi2);
107 return ((u64)tbhi << 32) | tblo;
109 #endif /* !CONFIG_PPC64 */
111 static inline u64 get_tb_or_rtc(void)
113 return __USE_RTC() ? get_rtc() : get_tb();
116 static inline void set_tb(unsigned int upper, unsigned int lower)
119 mtspr(SPRN_TBWU, upper);
120 mtspr(SPRN_TBWL, lower);
123 /* Accessor functions for the decrementer register.
124 * The 4xx doesn't even have a decrementer. I tried to use the
125 * generic timer interrupt code, which seems OK, with the 4xx PIT
126 * in auto-reload mode. The problem is PIT stops counting when it
127 * hits zero. If it would wrap, we could use it just like a decrementer.
129 static inline u64 get_dec(void)
131 #if defined(CONFIG_40x)
132 return (mfspr(SPRN_PIT));
134 return (mfspr(SPRN_DEC));
139 * Note: Book E and 4xx processors differ from other PowerPC processors
140 * in when the decrementer generates its interrupt: on the 1 to 0
141 * transition for Book E/4xx, but on the 0 to -1 transition for others.
143 static inline void set_dec(u64 val)
145 #if defined(CONFIG_40x)
146 mtspr(SPRN_PIT, (u32) val);
151 mtspr(SPRN_DEC, val);
155 static inline unsigned long tb_ticks_since(unsigned long tstamp)
158 int delta = get_rtcl() - (unsigned int) tstamp;
159 return delta < 0 ? delta + 1000000000 : delta;
161 return get_tbl() - tstamp;
164 #define mulhwu(x,y) \
165 ({unsigned z; asm ("mulhwu %0,%1,%2" : "=r" (z) : "r" (x), "r" (y)); z;})
168 #define mulhdu(x,y) \
169 ({unsigned long z; asm ("mulhdu %0,%1,%2" : "=r" (z) : "r" (x), "r" (y)); z;})
171 extern u64 mulhdu(u64, u64);
174 extern void div128_by_32(u64 dividend_high, u64 dividend_low,
175 unsigned divisor, struct div_result *dr);
177 extern void secondary_cpu_time_init(void);
178 extern void __init time_init(void);
180 DECLARE_PER_CPU(u64, decrementers_next_tb);
182 /* Convert timebase ticks to nanoseconds */
183 unsigned long long tb_to_ns(unsigned long long tb_ticks);
186 void accumulate_stolen_time(void);
188 #endif /* __KERNEL__ */
189 #endif /* __POWERPC_TIME_H */