xref: /openbmc/linux/arch/powerpc/include/asm/time.h (revision cfbb9be8)
1 /*
2  * Common time prototypes and such for all ppc machines.
3  *
4  * Written by Cort Dougan (cort@cs.nmt.edu) to merge
5  * Paul Mackerras' version and mine for PReP and Pmac.
6  *
7  * This program is free software; you can redistribute it and/or
8  * modify it under the terms of the GNU General Public License
9  * as published by the Free Software Foundation; either version
10  * 2 of the License, or (at your option) any later version.
11  */
12 
13 #ifndef __POWERPC_TIME_H
14 #define __POWERPC_TIME_H
15 
16 #ifdef __KERNEL__
17 #include <linux/types.h>
18 #include <linux/percpu.h>
19 
20 #include <asm/processor.h>
21 #include <asm/cpu_has_feature.h>
22 
23 /* time.c */
24 extern unsigned long tb_ticks_per_jiffy;
25 extern unsigned long tb_ticks_per_usec;
26 extern unsigned long tb_ticks_per_sec;
27 extern struct clock_event_device decrementer_clockevent;
28 
29 struct rtc_time;
30 extern void to_tm(int tim, struct rtc_time * tm);
31 extern void tick_broadcast_ipi_handler(void);
32 
33 extern void generic_calibrate_decr(void);
34 
35 /* Some sane defaults: 125 MHz timebase, 1GHz processor */
36 extern unsigned long ppc_proc_freq;
37 #define DEFAULT_PROC_FREQ	(DEFAULT_TB_FREQ * 8)
38 extern unsigned long ppc_tb_freq;
39 #define DEFAULT_TB_FREQ		125000000UL
40 
41 struct div_result {
42 	u64 result_high;
43 	u64 result_low;
44 };
45 
46 /* Accessor functions for the timebase (RTC on 601) registers. */
47 /* If one day CONFIG_POWER is added just define __USE_RTC as 1 */
48 #ifdef CONFIG_6xx
49 #define __USE_RTC()	(!cpu_has_feature(CPU_FTR_USE_TB))
50 #else
51 #define __USE_RTC()	0
52 #endif
53 
54 #ifdef CONFIG_PPC64
55 
56 /* For compatibility, get_tbl() is defined as get_tb() on ppc64 */
57 #define get_tbl		get_tb
58 
59 #else
60 
61 static inline unsigned long get_tbl(void)
62 {
63 #if defined(CONFIG_403GCX)
64 	unsigned long tbl;
65 	asm volatile("mfspr %0, 0x3dd" : "=r" (tbl));
66 	return tbl;
67 #else
68 	return mftbl();
69 #endif
70 }
71 
72 static inline unsigned int get_tbu(void)
73 {
74 #ifdef CONFIG_403GCX
75 	unsigned int tbu;
76 	asm volatile("mfspr %0, 0x3dc" : "=r" (tbu));
77 	return tbu;
78 #else
79 	return mftbu();
80 #endif
81 }
82 #endif /* !CONFIG_PPC64 */
83 
84 static inline unsigned int get_rtcl(void)
85 {
86 	unsigned int rtcl;
87 
88 	asm volatile("mfrtcl %0" : "=r" (rtcl));
89 	return rtcl;
90 }
91 
92 static inline u64 get_rtc(void)
93 {
94 	unsigned int hi, lo, hi2;
95 
96 	do {
97 		asm volatile("mfrtcu %0; mfrtcl %1; mfrtcu %2"
98 			     : "=r" (hi), "=r" (lo), "=r" (hi2));
99 	} while (hi2 != hi);
100 	return (u64)hi * 1000000000 + lo;
101 }
102 
103 static inline u64 get_vtb(void)
104 {
105 #ifdef CONFIG_PPC_BOOK3S_64
106 	if (cpu_has_feature(CPU_FTR_ARCH_207S))
107 		return mfspr(SPRN_VTB);
108 #endif
109 	return 0;
110 }
111 
112 #ifdef CONFIG_PPC64
113 static inline u64 get_tb(void)
114 {
115 	return mftb();
116 }
117 #else /* CONFIG_PPC64 */
118 static inline u64 get_tb(void)
119 {
120 	unsigned int tbhi, tblo, tbhi2;
121 
122 	do {
123 		tbhi = get_tbu();
124 		tblo = get_tbl();
125 		tbhi2 = get_tbu();
126 	} while (tbhi != tbhi2);
127 
128 	return ((u64)tbhi << 32) | tblo;
129 }
130 #endif /* !CONFIG_PPC64 */
131 
132 static inline u64 get_tb_or_rtc(void)
133 {
134 	return __USE_RTC() ? get_rtc() : get_tb();
135 }
136 
137 static inline void set_tb(unsigned int upper, unsigned int lower)
138 {
139 	mtspr(SPRN_TBWL, 0);
140 	mtspr(SPRN_TBWU, upper);
141 	mtspr(SPRN_TBWL, lower);
142 }
143 
144 /* Accessor functions for the decrementer register.
145  * The 4xx doesn't even have a decrementer.  I tried to use the
146  * generic timer interrupt code, which seems OK, with the 4xx PIT
147  * in auto-reload mode.  The problem is PIT stops counting when it
148  * hits zero.  If it would wrap, we could use it just like a decrementer.
149  */
150 static inline u64 get_dec(void)
151 {
152 #if defined(CONFIG_40x)
153 	return (mfspr(SPRN_PIT));
154 #else
155 	return (mfspr(SPRN_DEC));
156 #endif
157 }
158 
159 /*
160  * Note: Book E and 4xx processors differ from other PowerPC processors
161  * in when the decrementer generates its interrupt: on the 1 to 0
162  * transition for Book E/4xx, but on the 0 to -1 transition for others.
163  */
164 static inline void set_dec(u64 val)
165 {
166 #if defined(CONFIG_40x)
167 	mtspr(SPRN_PIT, (u32) val);
168 #else
169 #ifndef CONFIG_BOOKE
170 	--val;
171 #endif
172 	mtspr(SPRN_DEC, val);
173 #endif /* not 40x */
174 }
175 
176 static inline unsigned long tb_ticks_since(unsigned long tstamp)
177 {
178 	if (__USE_RTC()) {
179 		int delta = get_rtcl() - (unsigned int) tstamp;
180 		return delta < 0 ? delta + 1000000000 : delta;
181 	}
182 	return get_tbl() - tstamp;
183 }
184 
185 #define mulhwu(x,y) \
186 ({unsigned z; asm ("mulhwu %0,%1,%2" : "=r" (z) : "r" (x), "r" (y)); z;})
187 
188 #ifdef CONFIG_PPC64
189 #define mulhdu(x,y) \
190 ({unsigned long z; asm ("mulhdu %0,%1,%2" : "=r" (z) : "r" (x), "r" (y)); z;})
191 #else
192 extern u64 mulhdu(u64, u64);
193 #endif
194 
195 extern void div128_by_32(u64 dividend_high, u64 dividend_low,
196 			 unsigned divisor, struct div_result *dr);
197 
198 /* Used to store Processor Utilization register (purr) values */
199 
200 struct cpu_usage {
201         u64 current_tb;  /* Holds the current purr register values */
202 };
203 
204 DECLARE_PER_CPU(struct cpu_usage, cpu_usage_array);
205 
206 extern void secondary_cpu_time_init(void);
207 
208 DECLARE_PER_CPU(u64, decrementers_next_tb);
209 
210 /* Convert timebase ticks to nanoseconds */
211 unsigned long long tb_to_ns(unsigned long long tb_ticks);
212 
213 #endif /* __KERNEL__ */
214 #endif /* __POWERPC_TIME_H */
215