xref: /openbmc/linux/arch/powerpc/include/asm/time.h (revision 2359ccdd)
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 extern void hdec_interrupt(struct pt_regs *regs);
35 
36 /* Some sane defaults: 125 MHz timebase, 1GHz processor */
37 extern unsigned long ppc_proc_freq;
38 #define DEFAULT_PROC_FREQ	(DEFAULT_TB_FREQ * 8)
39 extern unsigned long ppc_tb_freq;
40 #define DEFAULT_TB_FREQ		125000000UL
41 
42 struct div_result {
43 	u64 result_high;
44 	u64 result_low;
45 };
46 
47 /* Accessor functions for the timebase (RTC on 601) registers. */
48 /* If one day CONFIG_POWER is added just define __USE_RTC as 1 */
49 #ifdef CONFIG_6xx
50 #define __USE_RTC()	(cpu_has_feature(CPU_FTR_USE_RTC))
51 #else
52 #define __USE_RTC()	0
53 #endif
54 
55 #ifdef CONFIG_PPC64
56 
57 /* For compatibility, get_tbl() is defined as get_tb() on ppc64 */
58 #define get_tbl		get_tb
59 
60 #else
61 
62 static inline unsigned long get_tbl(void)
63 {
64 #if defined(CONFIG_403GCX)
65 	unsigned long tbl;
66 	asm volatile("mfspr %0, 0x3dd" : "=r" (tbl));
67 	return tbl;
68 #else
69 	return mftbl();
70 #endif
71 }
72 
73 static inline unsigned int get_tbu(void)
74 {
75 #ifdef CONFIG_403GCX
76 	unsigned int tbu;
77 	asm volatile("mfspr %0, 0x3dc" : "=r" (tbu));
78 	return tbu;
79 #else
80 	return mftbu();
81 #endif
82 }
83 #endif /* !CONFIG_PPC64 */
84 
85 static inline unsigned int get_rtcl(void)
86 {
87 	unsigned int rtcl;
88 
89 	asm volatile("mfrtcl %0" : "=r" (rtcl));
90 	return rtcl;
91 }
92 
93 static inline u64 get_rtc(void)
94 {
95 	unsigned int hi, lo, hi2;
96 
97 	do {
98 		asm volatile("mfrtcu %0; mfrtcl %1; mfrtcu %2"
99 			     : "=r" (hi), "=r" (lo), "=r" (hi2));
100 	} while (hi2 != hi);
101 	return (u64)hi * 1000000000 + lo;
102 }
103 
104 static inline u64 get_vtb(void)
105 {
106 #ifdef CONFIG_PPC_BOOK3S_64
107 	if (cpu_has_feature(CPU_FTR_ARCH_207S))
108 		return mfspr(SPRN_VTB);
109 #endif
110 	return 0;
111 }
112 
113 #ifdef CONFIG_PPC64
114 static inline u64 get_tb(void)
115 {
116 	return mftb();
117 }
118 #else /* CONFIG_PPC64 */
119 static inline u64 get_tb(void)
120 {
121 	unsigned int tbhi, tblo, tbhi2;
122 
123 	do {
124 		tbhi = get_tbu();
125 		tblo = get_tbl();
126 		tbhi2 = get_tbu();
127 	} while (tbhi != tbhi2);
128 
129 	return ((u64)tbhi << 32) | tblo;
130 }
131 #endif /* !CONFIG_PPC64 */
132 
133 static inline u64 get_tb_or_rtc(void)
134 {
135 	return __USE_RTC() ? get_rtc() : get_tb();
136 }
137 
138 static inline void set_tb(unsigned int upper, unsigned int lower)
139 {
140 	mtspr(SPRN_TBWL, 0);
141 	mtspr(SPRN_TBWU, upper);
142 	mtspr(SPRN_TBWL, lower);
143 }
144 
145 /* Accessor functions for the decrementer register.
146  * The 4xx doesn't even have a decrementer.  I tried to use the
147  * generic timer interrupt code, which seems OK, with the 4xx PIT
148  * in auto-reload mode.  The problem is PIT stops counting when it
149  * hits zero.  If it would wrap, we could use it just like a decrementer.
150  */
151 static inline u64 get_dec(void)
152 {
153 #if defined(CONFIG_40x)
154 	return (mfspr(SPRN_PIT));
155 #else
156 	return (mfspr(SPRN_DEC));
157 #endif
158 }
159 
160 /*
161  * Note: Book E and 4xx processors differ from other PowerPC processors
162  * in when the decrementer generates its interrupt: on the 1 to 0
163  * transition for Book E/4xx, but on the 0 to -1 transition for others.
164  */
165 static inline void set_dec(u64 val)
166 {
167 #if defined(CONFIG_40x)
168 	mtspr(SPRN_PIT, (u32) val);
169 #else
170 #ifndef CONFIG_BOOKE
171 	--val;
172 #endif
173 	mtspr(SPRN_DEC, val);
174 #endif /* not 40x */
175 }
176 
177 static inline unsigned long tb_ticks_since(unsigned long tstamp)
178 {
179 	if (__USE_RTC()) {
180 		int delta = get_rtcl() - (unsigned int) tstamp;
181 		return delta < 0 ? delta + 1000000000 : delta;
182 	}
183 	return get_tbl() - tstamp;
184 }
185 
186 #define mulhwu(x,y) \
187 ({unsigned z; asm ("mulhwu %0,%1,%2" : "=r" (z) : "r" (x), "r" (y)); z;})
188 
189 #ifdef CONFIG_PPC64
190 #define mulhdu(x,y) \
191 ({unsigned long z; asm ("mulhdu %0,%1,%2" : "=r" (z) : "r" (x), "r" (y)); z;})
192 #else
193 extern u64 mulhdu(u64, u64);
194 #endif
195 
196 extern void div128_by_32(u64 dividend_high, u64 dividend_low,
197 			 unsigned divisor, struct div_result *dr);
198 
199 /* Used to store Processor Utilization register (purr) values */
200 
201 struct cpu_usage {
202         u64 current_tb;  /* Holds the current purr register values */
203 };
204 
205 DECLARE_PER_CPU(struct cpu_usage, cpu_usage_array);
206 
207 extern void secondary_cpu_time_init(void);
208 extern void __init time_init(void);
209 
210 DECLARE_PER_CPU(u64, decrementers_next_tb);
211 
212 /* Convert timebase ticks to nanoseconds */
213 unsigned long long tb_to_ns(unsigned long long tb_ticks);
214 
215 #endif /* __KERNEL__ */
216 #endif /* __POWERPC_TIME_H */
217