xref: /openbmc/linux/arch/powerpc/include/asm/time.h (revision db181ce0)
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 
22 /* time.c */
23 extern unsigned long tb_ticks_per_jiffy;
24 extern unsigned long tb_ticks_per_usec;
25 extern unsigned long tb_ticks_per_sec;
26 extern struct clock_event_device decrementer_clockevent;
27 
28 struct rtc_time;
29 extern void to_tm(int tim, struct rtc_time * tm);
30 extern void GregorianDay(struct rtc_time *tm);
31 extern void tick_broadcast_ipi_handler(void);
32 
33 extern void generic_calibrate_decr(void);
34 
35 extern void set_dec_cpu6(unsigned int val);
36 
37 /* Some sane defaults: 125 MHz timebase, 1GHz processor */
38 extern unsigned long ppc_proc_freq;
39 #define DEFAULT_PROC_FREQ	(DEFAULT_TB_FREQ * 8)
40 extern unsigned long ppc_tb_freq;
41 #define DEFAULT_TB_FREQ		125000000UL
42 
43 struct div_result {
44 	u64 result_high;
45 	u64 result_low;
46 };
47 
48 /* Accessor functions for the timebase (RTC on 601) registers. */
49 /* If one day CONFIG_POWER is added just define __USE_RTC as 1 */
50 #ifdef CONFIG_6xx
51 #define __USE_RTC()	(!cpu_has_feature(CPU_FTR_USE_TB))
52 #else
53 #define __USE_RTC()	0
54 #endif
55 
56 #ifdef CONFIG_PPC64
57 
58 /* For compatibility, get_tbl() is defined as get_tb() on ppc64 */
59 #define get_tbl		get_tb
60 
61 #else
62 
63 static inline unsigned long get_tbl(void)
64 {
65 #if defined(CONFIG_403GCX)
66 	unsigned long tbl;
67 	asm volatile("mfspr %0, 0x3dd" : "=r" (tbl));
68 	return tbl;
69 #else
70 	return mftbl();
71 #endif
72 }
73 
74 static inline unsigned int get_tbu(void)
75 {
76 #ifdef CONFIG_403GCX
77 	unsigned int tbu;
78 	asm volatile("mfspr %0, 0x3dc" : "=r" (tbu));
79 	return tbu;
80 #else
81 	return mftbu();
82 #endif
83 }
84 #endif /* !CONFIG_PPC64 */
85 
86 static inline unsigned int get_rtcl(void)
87 {
88 	unsigned int rtcl;
89 
90 	asm volatile("mfrtcl %0" : "=r" (rtcl));
91 	return rtcl;
92 }
93 
94 static inline u64 get_rtc(void)
95 {
96 	unsigned int hi, lo, hi2;
97 
98 	do {
99 		asm volatile("mfrtcu %0; mfrtcl %1; mfrtcu %2"
100 			     : "=r" (hi), "=r" (lo), "=r" (hi2));
101 	} while (hi2 != hi);
102 	return (u64)hi * 1000000000 + lo;
103 }
104 
105 #ifdef CONFIG_PPC64
106 static inline u64 get_tb(void)
107 {
108 	return mftb();
109 }
110 #else /* CONFIG_PPC64 */
111 static inline u64 get_tb(void)
112 {
113 	unsigned int tbhi, tblo, tbhi2;
114 
115 	do {
116 		tbhi = get_tbu();
117 		tblo = get_tbl();
118 		tbhi2 = get_tbu();
119 	} while (tbhi != tbhi2);
120 
121 	return ((u64)tbhi << 32) | tblo;
122 }
123 #endif /* !CONFIG_PPC64 */
124 
125 static inline u64 get_tb_or_rtc(void)
126 {
127 	return __USE_RTC() ? get_rtc() : get_tb();
128 }
129 
130 static inline void set_tb(unsigned int upper, unsigned int lower)
131 {
132 	mtspr(SPRN_TBWL, 0);
133 	mtspr(SPRN_TBWU, upper);
134 	mtspr(SPRN_TBWL, lower);
135 }
136 
137 /* Accessor functions for the decrementer register.
138  * The 4xx doesn't even have a decrementer.  I tried to use the
139  * generic timer interrupt code, which seems OK, with the 4xx PIT
140  * in auto-reload mode.  The problem is PIT stops counting when it
141  * hits zero.  If it would wrap, we could use it just like a decrementer.
142  */
143 static inline unsigned int get_dec(void)
144 {
145 #if defined(CONFIG_40x)
146 	return (mfspr(SPRN_PIT));
147 #else
148 	return (mfspr(SPRN_DEC));
149 #endif
150 }
151 
152 /*
153  * Note: Book E and 4xx processors differ from other PowerPC processors
154  * in when the decrementer generates its interrupt: on the 1 to 0
155  * transition for Book E/4xx, but on the 0 to -1 transition for others.
156  */
157 static inline void set_dec(int val)
158 {
159 #if defined(CONFIG_40x)
160 	mtspr(SPRN_PIT, val);
161 #elif defined(CONFIG_8xx_CPU6)
162 	set_dec_cpu6(val - 1);
163 #else
164 #ifndef CONFIG_BOOKE
165 	--val;
166 #endif
167 	mtspr(SPRN_DEC, val);
168 #endif /* not 40x or 8xx_CPU6 */
169 }
170 
171 static inline unsigned long tb_ticks_since(unsigned long tstamp)
172 {
173 	if (__USE_RTC()) {
174 		int delta = get_rtcl() - (unsigned int) tstamp;
175 		return delta < 0 ? delta + 1000000000 : delta;
176 	}
177 	return get_tbl() - tstamp;
178 }
179 
180 #define mulhwu(x,y) \
181 ({unsigned z; asm ("mulhwu %0,%1,%2" : "=r" (z) : "r" (x), "r" (y)); z;})
182 
183 #ifdef CONFIG_PPC64
184 #define mulhdu(x,y) \
185 ({unsigned long z; asm ("mulhdu %0,%1,%2" : "=r" (z) : "r" (x), "r" (y)); z;})
186 #else
187 extern u64 mulhdu(u64, u64);
188 #endif
189 
190 extern void div128_by_32(u64 dividend_high, u64 dividend_low,
191 			 unsigned divisor, struct div_result *dr);
192 
193 /* Used to store Processor Utilization register (purr) values */
194 
195 struct cpu_usage {
196         u64 current_tb;  /* Holds the current purr register values */
197 };
198 
199 DECLARE_PER_CPU(struct cpu_usage, cpu_usage_array);
200 
201 extern void secondary_cpu_time_init(void);
202 
203 DECLARE_PER_CPU(u64, decrementers_next_tb);
204 
205 #endif /* __KERNEL__ */
206 #endif /* __POWERPC_TIME_H */
207