xref: /linux/arch/powerpc/include/asm/time.h (revision 0883c2c06fb5bcf5b9e008270827e63c09a88c1e)
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 tick_broadcast_ipi_handler(void);
31 
32 extern void generic_calibrate_decr(void);
33 
34 /* Some sane defaults: 125 MHz timebase, 1GHz processor */
35 extern unsigned long ppc_proc_freq;
36 #define DEFAULT_PROC_FREQ	(DEFAULT_TB_FREQ * 8)
37 extern unsigned long ppc_tb_freq;
38 #define DEFAULT_TB_FREQ		125000000UL
39 
40 struct div_result {
41 	u64 result_high;
42 	u64 result_low;
43 };
44 
45 /* Accessor functions for the timebase (RTC on 601) registers. */
46 /* If one day CONFIG_POWER is added just define __USE_RTC as 1 */
47 #ifdef CONFIG_6xx
48 #define __USE_RTC()	(!cpu_has_feature(CPU_FTR_USE_TB))
49 #else
50 #define __USE_RTC()	0
51 #endif
52 
53 #ifdef CONFIG_PPC64
54 
55 /* For compatibility, get_tbl() is defined as get_tb() on ppc64 */
56 #define get_tbl		get_tb
57 
58 #else
59 
60 static inline unsigned long get_tbl(void)
61 {
62 #if defined(CONFIG_403GCX)
63 	unsigned long tbl;
64 	asm volatile("mfspr %0, 0x3dd" : "=r" (tbl));
65 	return tbl;
66 #else
67 	return mftbl();
68 #endif
69 }
70 
71 static inline unsigned int get_tbu(void)
72 {
73 #ifdef CONFIG_403GCX
74 	unsigned int tbu;
75 	asm volatile("mfspr %0, 0x3dc" : "=r" (tbu));
76 	return tbu;
77 #else
78 	return mftbu();
79 #endif
80 }
81 #endif /* !CONFIG_PPC64 */
82 
83 static inline unsigned int get_rtcl(void)
84 {
85 	unsigned int rtcl;
86 
87 	asm volatile("mfrtcl %0" : "=r" (rtcl));
88 	return rtcl;
89 }
90 
91 static inline u64 get_rtc(void)
92 {
93 	unsigned int hi, lo, hi2;
94 
95 	do {
96 		asm volatile("mfrtcu %0; mfrtcl %1; mfrtcu %2"
97 			     : "=r" (hi), "=r" (lo), "=r" (hi2));
98 	} while (hi2 != hi);
99 	return (u64)hi * 1000000000 + lo;
100 }
101 
102 static inline u64 get_vtb(void)
103 {
104 #ifdef CONFIG_PPC_BOOK3S_64
105 	if (cpu_has_feature(CPU_FTR_ARCH_207S))
106 		return mfvtb();
107 #endif
108 	return 0;
109 }
110 
111 #ifdef CONFIG_PPC64
112 static inline u64 get_tb(void)
113 {
114 	return mftb();
115 }
116 #else /* CONFIG_PPC64 */
117 static inline u64 get_tb(void)
118 {
119 	unsigned int tbhi, tblo, tbhi2;
120 
121 	do {
122 		tbhi = get_tbu();
123 		tblo = get_tbl();
124 		tbhi2 = get_tbu();
125 	} while (tbhi != tbhi2);
126 
127 	return ((u64)tbhi << 32) | tblo;
128 }
129 #endif /* !CONFIG_PPC64 */
130 
131 static inline u64 get_tb_or_rtc(void)
132 {
133 	return __USE_RTC() ? get_rtc() : get_tb();
134 }
135 
136 static inline void set_tb(unsigned int upper, unsigned int lower)
137 {
138 	mtspr(SPRN_TBWL, 0);
139 	mtspr(SPRN_TBWU, upper);
140 	mtspr(SPRN_TBWL, lower);
141 }
142 
143 /* Accessor functions for the decrementer register.
144  * The 4xx doesn't even have a decrementer.  I tried to use the
145  * generic timer interrupt code, which seems OK, with the 4xx PIT
146  * in auto-reload mode.  The problem is PIT stops counting when it
147  * hits zero.  If it would wrap, we could use it just like a decrementer.
148  */
149 static inline u64 get_dec(void)
150 {
151 #if defined(CONFIG_40x)
152 	return (mfspr(SPRN_PIT));
153 #else
154 	return (mfspr(SPRN_DEC));
155 #endif
156 }
157 
158 /*
159  * Note: Book E and 4xx processors differ from other PowerPC processors
160  * in when the decrementer generates its interrupt: on the 1 to 0
161  * transition for Book E/4xx, but on the 0 to -1 transition for others.
162  */
163 static inline void set_dec(u64 val)
164 {
165 #if defined(CONFIG_40x)
166 	mtspr(SPRN_PIT, (u32) val);
167 #else
168 #ifndef CONFIG_BOOKE
169 	--val;
170 #endif
171 	mtspr(SPRN_DEC, val);
172 #endif /* not 40x */
173 }
174 
175 static inline unsigned long tb_ticks_since(unsigned long tstamp)
176 {
177 	if (__USE_RTC()) {
178 		int delta = get_rtcl() - (unsigned int) tstamp;
179 		return delta < 0 ? delta + 1000000000 : delta;
180 	}
181 	return get_tbl() - tstamp;
182 }
183 
184 #define mulhwu(x,y) \
185 ({unsigned z; asm ("mulhwu %0,%1,%2" : "=r" (z) : "r" (x), "r" (y)); z;})
186 
187 #ifdef CONFIG_PPC64
188 #define mulhdu(x,y) \
189 ({unsigned long z; asm ("mulhdu %0,%1,%2" : "=r" (z) : "r" (x), "r" (y)); z;})
190 #else
191 extern u64 mulhdu(u64, u64);
192 #endif
193 
194 extern void div128_by_32(u64 dividend_high, u64 dividend_low,
195 			 unsigned divisor, struct div_result *dr);
196 
197 /* Used to store Processor Utilization register (purr) values */
198 
199 struct cpu_usage {
200         u64 current_tb;  /* Holds the current purr register values */
201 };
202 
203 DECLARE_PER_CPU(struct cpu_usage, cpu_usage_array);
204 
205 extern void secondary_cpu_time_init(void);
206 
207 DECLARE_PER_CPU(u64, decrementers_next_tb);
208 
209 /* Convert timebase ticks to nanoseconds */
210 unsigned long long tb_to_ns(unsigned long long tb_ticks);
211 
212 #endif /* __KERNEL__ */
213 #endif /* __POWERPC_TIME_H */
214