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 extern void hdec_interrupt(struct pt_regs *regs);
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 /* 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))
45
46 #ifdef CONFIG_PPC64
47
48 /* For compatibility, get_tbl() is defined as get_tb() on ppc64 */
49 #define get_tbl get_tb
50
51 #else
52
get_tbl(void)53 static inline unsigned long get_tbl(void)
54 {
55 #if defined(CONFIG_403GCX)
56 unsigned long tbl;
57 asm volatile("mfspr %0, 0x3dd" : "=r" (tbl));
58 return tbl;
59 #else
60 return mftbl();
61 #endif
62 }
63
get_tbu(void)64 static inline unsigned int get_tbu(void)
65 {
66 #ifdef CONFIG_403GCX
67 unsigned int tbu;
68 asm volatile("mfspr %0, 0x3dc" : "=r" (tbu));
69 return tbu;
70 #else
71 return mftbu();
72 #endif
73 }
74 #endif /* !CONFIG_PPC64 */
75
get_rtcl(void)76 static inline unsigned int get_rtcl(void)
77 {
78 unsigned int rtcl;
79
80 asm volatile("mfrtcl %0" : "=r" (rtcl));
81 return rtcl;
82 }
83
get_rtc(void)84 static inline u64 get_rtc(void)
85 {
86 unsigned int hi, lo, hi2;
87
88 do {
89 asm volatile("mfrtcu %0; mfrtcl %1; mfrtcu %2"
90 : "=r" (hi), "=r" (lo), "=r" (hi2));
91 } while (hi2 != hi);
92 return (u64)hi * 1000000000 + lo;
93 }
94
get_vtb(void)95 static inline u64 get_vtb(void)
96 {
97 #ifdef CONFIG_PPC_BOOK3S_64
98 if (cpu_has_feature(CPU_FTR_ARCH_207S))
99 return mfspr(SPRN_VTB);
100 #endif
101 return 0;
102 }
103
104 #ifdef CONFIG_PPC64
get_tb(void)105 static inline u64 get_tb(void)
106 {
107 return mftb();
108 }
109 #else /* CONFIG_PPC64 */
get_tb(void)110 static inline u64 get_tb(void)
111 {
112 unsigned int tbhi, tblo, tbhi2;
113
114 do {
115 tbhi = get_tbu();
116 tblo = get_tbl();
117 tbhi2 = get_tbu();
118 } while (tbhi != tbhi2);
119
120 return ((u64)tbhi << 32) | tblo;
121 }
122 #endif /* !CONFIG_PPC64 */
123
get_tb_or_rtc(void)124 static inline u64 get_tb_or_rtc(void)
125 {
126 return __USE_RTC() ? get_rtc() : get_tb();
127 }
128
set_tb(unsigned int upper,unsigned int lower)129 static inline void set_tb(unsigned int upper, unsigned int lower)
130 {
131 mtspr(SPRN_TBWL, 0);
132 mtspr(SPRN_TBWU, upper);
133 mtspr(SPRN_TBWL, lower);
134 }
135
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.
141 */
get_dec(void)142 static inline u64 get_dec(void)
143 {
144 #if defined(CONFIG_40x)
145 return (mfspr(SPRN_PIT));
146 #else
147 return (mfspr(SPRN_DEC));
148 #endif
149 }
150
151 /*
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.
155 */
set_dec(u64 val)156 static inline void set_dec(u64 val)
157 {
158 #if defined(CONFIG_40x)
159 mtspr(SPRN_PIT, (u32) val);
160 #else
161 #ifndef CONFIG_BOOKE
162 --val;
163 #endif
164 mtspr(SPRN_DEC, val);
165 #endif /* not 40x */
166 }
167
tb_ticks_since(unsigned long tstamp)168 static inline unsigned long tb_ticks_since(unsigned long tstamp)
169 {
170 if (__USE_RTC()) {
171 int delta = get_rtcl() - (unsigned int) tstamp;
172 return delta < 0 ? delta + 1000000000 : delta;
173 }
174 return get_tbl() - tstamp;
175 }
176
177 #define mulhwu(x,y) \
178 ({unsigned z; asm ("mulhwu %0,%1,%2" : "=r" (z) : "r" (x), "r" (y)); z;})
179
180 #ifdef CONFIG_PPC64
181 #define mulhdu(x,y) \
182 ({unsigned long z; asm ("mulhdu %0,%1,%2" : "=r" (z) : "r" (x), "r" (y)); z;})
183 #else
184 extern u64 mulhdu(u64, u64);
185 #endif
186
187 extern void div128_by_32(u64 dividend_high, u64 dividend_low,
188 unsigned divisor, struct div_result *dr);
189
190 extern void secondary_cpu_time_init(void);
191 extern void __init time_init(void);
192
193 DECLARE_PER_CPU(u64, decrementers_next_tb);
194
195 /* Convert timebase ticks to nanoseconds */
196 unsigned long long tb_to_ns(unsigned long long tb_ticks);
197
198 #endif /* __KERNEL__ */
199 #endif /* __POWERPC_TIME_H */
200
