xref: /openbmc/linux/arch/powerpc/include/asm/time.h (revision 9ac8d3fb)
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 #ifdef CONFIG_PPC_ISERIES
22 #include <asm/paca.h>
23 #include <asm/firmware.h>
24 #include <asm/iseries/hv_call.h>
25 #endif
26 
27 /* time.c */
28 extern unsigned long tb_ticks_per_jiffy;
29 extern unsigned long tb_ticks_per_usec;
30 extern unsigned long tb_ticks_per_sec;
31 extern u64 tb_to_xs;
32 extern unsigned      tb_to_us;
33 
34 struct rtc_time;
35 extern void to_tm(int tim, struct rtc_time * tm);
36 extern void GregorianDay(struct rtc_time *tm);
37 extern time_t last_rtc_update;
38 
39 extern void generic_calibrate_decr(void);
40 extern void wakeup_decrementer(void);
41 extern void snapshot_timebase(void);
42 
43 extern void set_dec_cpu6(unsigned int val);
44 
45 /* Some sane defaults: 125 MHz timebase, 1GHz processor */
46 extern unsigned long ppc_proc_freq;
47 #define DEFAULT_PROC_FREQ	(DEFAULT_TB_FREQ * 8)
48 extern unsigned long ppc_tb_freq;
49 #define DEFAULT_TB_FREQ		125000000UL
50 
51 /*
52  * By putting all of this stuff into a single struct we
53  * reduce the number of cache lines touched by do_gettimeofday.
54  * Both by collecting all of the data in one cache line and
55  * by touching only one TOC entry on ppc64.
56  */
57 struct gettimeofday_vars {
58 	u64 tb_to_xs;
59 	u64 stamp_xsec;
60 	u64 tb_orig_stamp;
61 };
62 
63 struct gettimeofday_struct {
64 	unsigned long tb_ticks_per_sec;
65 	struct gettimeofday_vars vars[2];
66 	struct gettimeofday_vars * volatile varp;
67 	unsigned      var_idx;
68 	unsigned      tb_to_us;
69 };
70 
71 struct div_result {
72 	u64 result_high;
73 	u64 result_low;
74 };
75 
76 /* Accessor functions for the timebase (RTC on 601) registers. */
77 /* If one day CONFIG_POWER is added just define __USE_RTC as 1 */
78 #ifdef CONFIG_6xx
79 #define __USE_RTC()	(!cpu_has_feature(CPU_FTR_USE_TB))
80 #else
81 #define __USE_RTC()	0
82 #endif
83 
84 #ifdef CONFIG_PPC64
85 
86 /* For compatibility, get_tbl() is defined as get_tb() on ppc64 */
87 #define get_tbl		get_tb
88 
89 #else
90 
91 static inline unsigned long get_tbl(void)
92 {
93 #if defined(CONFIG_403GCX)
94 	unsigned long tbl;
95 	asm volatile("mfspr %0, 0x3dd" : "=r" (tbl));
96 	return tbl;
97 #else
98 	return mftbl();
99 #endif
100 }
101 
102 static inline unsigned int get_tbu(void)
103 {
104 #ifdef CONFIG_403GCX
105 	unsigned int tbu;
106 	asm volatile("mfspr %0, 0x3dc" : "=r" (tbu));
107 	return tbu;
108 #else
109 	return mftbu();
110 #endif
111 }
112 #endif /* !CONFIG_PPC64 */
113 
114 static inline unsigned int get_rtcl(void)
115 {
116 	unsigned int rtcl;
117 
118 	asm volatile("mfrtcl %0" : "=r" (rtcl));
119 	return rtcl;
120 }
121 
122 static inline u64 get_rtc(void)
123 {
124 	unsigned int hi, lo, hi2;
125 
126 	do {
127 		asm volatile("mfrtcu %0; mfrtcl %1; mfrtcu %2"
128 			     : "=r" (hi), "=r" (lo), "=r" (hi2));
129 	} while (hi2 != hi);
130 	return (u64)hi * 1000000000 + lo;
131 }
132 
133 #ifdef CONFIG_PPC64
134 static inline u64 get_tb(void)
135 {
136 	return mftb();
137 }
138 #else /* CONFIG_PPC64 */
139 static inline u64 get_tb(void)
140 {
141 	unsigned int tbhi, tblo, tbhi2;
142 
143 	do {
144 		tbhi = get_tbu();
145 		tblo = get_tbl();
146 		tbhi2 = get_tbu();
147 	} while (tbhi != tbhi2);
148 
149 	return ((u64)tbhi << 32) | tblo;
150 }
151 #endif /* !CONFIG_PPC64 */
152 
153 static inline u64 get_tb_or_rtc(void)
154 {
155 	return __USE_RTC() ? get_rtc() : get_tb();
156 }
157 
158 static inline void set_tb(unsigned int upper, unsigned int lower)
159 {
160 	mtspr(SPRN_TBWL, 0);
161 	mtspr(SPRN_TBWU, upper);
162 	mtspr(SPRN_TBWL, lower);
163 }
164 
165 /* Accessor functions for the decrementer register.
166  * The 4xx doesn't even have a decrementer.  I tried to use the
167  * generic timer interrupt code, which seems OK, with the 4xx PIT
168  * in auto-reload mode.  The problem is PIT stops counting when it
169  * hits zero.  If it would wrap, we could use it just like a decrementer.
170  */
171 static inline unsigned int get_dec(void)
172 {
173 #if defined(CONFIG_40x)
174 	return (mfspr(SPRN_PIT));
175 #else
176 	return (mfspr(SPRN_DEC));
177 #endif
178 }
179 
180 /*
181  * Note: Book E and 4xx processors differ from other PowerPC processors
182  * in when the decrementer generates its interrupt: on the 1 to 0
183  * transition for Book E/4xx, but on the 0 to -1 transition for others.
184  */
185 static inline void set_dec(int val)
186 {
187 #if defined(CONFIG_40x)
188 	mtspr(SPRN_PIT, val);
189 #elif defined(CONFIG_8xx_CPU6)
190 	set_dec_cpu6(val - 1);
191 #else
192 #ifndef CONFIG_BOOKE
193 	--val;
194 #endif
195 #ifdef CONFIG_PPC_ISERIES
196 	if (firmware_has_feature(FW_FEATURE_ISERIES) &&
197 			get_lppaca()->shared_proc) {
198 		get_lppaca()->virtual_decr = val;
199 		if (get_dec() > val)
200 			HvCall_setVirtualDecr();
201 		return;
202 	}
203 #endif
204 	mtspr(SPRN_DEC, val);
205 #endif /* not 40x or 8xx_CPU6 */
206 }
207 
208 static inline unsigned long tb_ticks_since(unsigned long tstamp)
209 {
210 	if (__USE_RTC()) {
211 		int delta = get_rtcl() - (unsigned int) tstamp;
212 		return delta < 0 ? delta + 1000000000 : delta;
213 	}
214 	return get_tbl() - tstamp;
215 }
216 
217 #define mulhwu(x,y) \
218 ({unsigned z; asm ("mulhwu %0,%1,%2" : "=r" (z) : "r" (x), "r" (y)); z;})
219 
220 #ifdef CONFIG_PPC64
221 #define mulhdu(x,y) \
222 ({unsigned long z; asm ("mulhdu %0,%1,%2" : "=r" (z) : "r" (x), "r" (y)); z;})
223 #else
224 extern u64 mulhdu(u64, u64);
225 #endif
226 
227 extern void smp_space_timers(unsigned int);
228 
229 extern unsigned mulhwu_scale_factor(unsigned, unsigned);
230 extern void div128_by_32(u64 dividend_high, u64 dividend_low,
231 			 unsigned divisor, struct div_result *dr);
232 
233 /* Used to store Processor Utilization register (purr) values */
234 
235 struct cpu_usage {
236         u64 current_tb;  /* Holds the current purr register values */
237 };
238 
239 DECLARE_PER_CPU(struct cpu_usage, cpu_usage_array);
240 
241 #if defined(CONFIG_VIRT_CPU_ACCOUNTING)
242 extern void calculate_steal_time(void);
243 extern void snapshot_timebases(void);
244 #define account_process_vtime(tsk)		account_process_tick(tsk, 0)
245 #else
246 #define calculate_steal_time()			do { } while (0)
247 #define snapshot_timebases()			do { } while (0)
248 #define account_process_vtime(tsk)		do { } while (0)
249 #endif
250 
251 extern void secondary_cpu_time_init(void);
252 extern void iSeries_time_init_early(void);
253 
254 #endif /* __KERNEL__ */
255 #endif /* __POWERPC_TIME_H */
256