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);
27 extern void hdec_interrupt(struct pt_regs *regs);
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
35 extern bool tb_invalid;
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))
48 /* For compatibility, get_tbl() is defined as get_tb() on ppc64 */
49 #define get_tbl get_tb
53 static inline unsigned long get_tbl(void)
55 #if defined(CONFIG_403GCX)
57 asm volatile("mfspr %0, 0x3dd" : "=r" (tbl));
64 static inline unsigned int get_tbu(void)
68 asm volatile("mfspr %0, 0x3dc" : "=r" (tbu));
74 #endif /* !CONFIG_PPC64 */
76 static inline unsigned int get_rtcl(void)
80 asm volatile("mfrtcl %0" : "=r" (rtcl));
84 static inline u64 get_rtc(void)
86 unsigned int hi, lo, hi2;
89 asm volatile("mfrtcu %0; mfrtcl %1; mfrtcu %2"
90 : "=r" (hi), "=r" (lo), "=r" (hi2));
92 return (u64)hi * 1000000000 + lo;
95 static inline u64 get_vtb(void)
97 #ifdef CONFIG_PPC_BOOK3S_64
98 if (cpu_has_feature(CPU_FTR_ARCH_207S))
99 return mfspr(SPRN_VTB);
105 static inline u64 get_tb(void)
109 #else /* CONFIG_PPC64 */
110 static inline u64 get_tb(void)
112 unsigned int tbhi, tblo, tbhi2;
118 } while (tbhi != tbhi2);
120 return ((u64)tbhi << 32) | tblo;
122 #endif /* !CONFIG_PPC64 */
124 static inline u64 get_tb_or_rtc(void)
126 return __USE_RTC() ? get_rtc() : get_tb();
129 static inline void set_tb(unsigned int upper, unsigned int lower)
132 mtspr(SPRN_TBWU, upper);
133 mtspr(SPRN_TBWL, lower);
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.
142 static inline u64 get_dec(void)
144 #if defined(CONFIG_40x)
145 return (mfspr(SPRN_PIT));
147 return (mfspr(SPRN_DEC));
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.
156 static inline void set_dec(u64 val)
158 #if defined(CONFIG_40x)
159 mtspr(SPRN_PIT, (u32) val);
164 mtspr(SPRN_DEC, val);
168 static inline unsigned long tb_ticks_since(unsigned long tstamp)
171 int delta = get_rtcl() - (unsigned int) tstamp;
172 return delta < 0 ? delta + 1000000000 : delta;
174 return get_tbl() - tstamp;
177 #define mulhwu(x,y) \
178 ({unsigned z; asm ("mulhwu %0,%1,%2" : "=r" (z) : "r" (x), "r" (y)); z;})
181 #define mulhdu(x,y) \
182 ({unsigned long z; asm ("mulhdu %0,%1,%2" : "=r" (z) : "r" (x), "r" (y)); z;})
184 extern u64 mulhdu(u64, u64);
187 extern void div128_by_32(u64 dividend_high, u64 dividend_low,
188 unsigned divisor, struct div_result *dr);
190 extern void secondary_cpu_time_init(void);
191 extern void __init time_init(void);
193 DECLARE_PER_CPU(u64, decrementers_next_tb);
195 /* Convert timebase ticks to nanoseconds */
196 unsigned long long tb_to_ns(unsigned long long tb_ticks);
198 #endif /* __KERNEL__ */
199 #endif /* __POWERPC_TIME_H */