include/asm-powerpc/time.h

   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/config.h>
  18 #include <linux/types.h>
  19 #include <linux/percpu.h>
  20
  21 #include <asm/processor.h>
  22 #ifdef CONFIG_PPC64
  23 #include <asm/paca.h>
  24 #include <asm/iSeries/HvCall.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 extern u64 tb_last_stamp;
  34
  35 DECLARE_PER_CPU(unsigned long, last_jiffy);
  36
  37 struct rtc_time;
  38 extern void to_tm(int tim, struct rtc_time * tm);
  39 extern time_t last_rtc_update;
  40
  41 extern void generic_calibrate_decr(void);
  42 extern void wakeup_decrementer(void);
  43
  44 /* Some sane defaults: 125 MHz timebase, 1GHz processor */
  45 extern unsigned long ppc_proc_freq;
  46 #define DEFAULT_PROC_FREQ       (DEFAULT_TB_FREQ * 8)
  47 extern unsigned long ppc_tb_freq;
  48 #define DEFAULT_TB_FREQ         125000000UL
  49
  50 /*
  51  * By putting all of this stuff into a single struct we
  52  * reduce the number of cache lines touched by do_gettimeofday.
  53  * Both by collecting all of the data in one cache line and
  54  * by touching only one TOC entry on ppc64.
  55  */
  56 struct gettimeofday_vars {
  57         u64 tb_to_xs;
  58         u64 stamp_xsec;
  59         u64 tb_orig_stamp;
  60 };
  61
  62 struct gettimeofday_struct {
  63         unsigned long tb_ticks_per_sec;
  64         struct gettimeofday_vars vars[2];
  65         struct gettimeofday_vars * volatile varp;
  66         unsigned      var_idx;
  67         unsigned      tb_to_us;
  68 };
  69
  70 struct div_result {
  71         u64 result_high;
  72         u64 result_low;
  73 };
  74
  75 /* Accessor functions for the timebase (RTC on 601) registers. */
  76 /* If one day CONFIG_POWER is added just define __USE_RTC as 1 */
  77 #ifdef CONFIG_6xx
  78 #define __USE_RTC()     cpu_has_feature(CPU_FTR_USE_TB)
  79 #else
  80 #define __USE_RTC()     0
  81 #endif
  82
  83 /* On ppc64 this gets us the whole timebase; on ppc32 just the lower half */
  84 static inline unsigned long get_tbl(void)
  85 {
  86         unsigned long tbl;
  87
  88 #if defined(CONFIG_403GCX)
  89         asm volatile("mfspr %0, 0x3dd" : "=r" (tbl));
  90 #else
  91         asm volatile("mftb %0" : "=r" (tbl));
  92 #endif
  93         return tbl;
  94 }
  95
  96 static inline unsigned int get_tbu(void)
  97 {
  98         unsigned int tbu;
  99
 100 #if defined(CONFIG_403GCX)
 101         asm volatile("mfspr %0, 0x3dc" : "=r" (tbu));
 102 #else
 103         asm volatile("mftbu %0" : "=r" (tbu));
 104 #endif
 105         return tbu;
 106 }
 107
 108 static inline unsigned int get_rtcl(void)
 109 {
 110         unsigned int rtcl;
 111
 112         asm volatile("mfrtcl %0" : "=r" (rtcl));
 113         return rtcl;
 114 }
 115
 116 #ifdef CONFIG_PPC64
 117 static inline u64 get_tb(void)
 118 {
 119         return mftb();
 120 }
 121 #else
 122 static inline u64 get_tb(void)
 123 {
 124         unsigned int tbhi, tblo, tbhi2;
 125
 126         do {
 127                 tbhi = get_tbu();
 128                 tblo = get_tbl();
 129                 tbhi2 = get_tbu();
 130         } while (tbhi != tbhi2);
 131
 132         return ((u64)tbhi << 32) | tblo;
 133 }
 134 #endif
 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 unsigned int 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 static inline void set_dec(int val)
 159 {
 160 #if defined(CONFIG_40x)
 161         return;         /* Have to let it auto-reload */
 162 #elif defined(CONFIG_8xx_CPU6)
 163         set_dec_cpu6(val);
 164 #else
 165 #ifdef CONFIG_PPC_ISERIES
 166         struct paca_struct *lpaca = get_paca();
 167         int cur_dec;
 168
 169         if (lpaca->lppaca.shared_proc) {
 170                 lpaca->lppaca.virtual_decr = val;
 171                 cur_dec = get_dec();
 172                 if (cur_dec > val)
 173                         HvCall_setVirtualDecr();
 174         } else
 175 #endif
 176                 mtspr(SPRN_DEC, val);
 177 #endif /* not 40x or 8xx_CPU6 */
 178 }
 179
 180 static inline unsigned long tb_ticks_since(unsigned long tstamp)
 181 {
 182         if (__USE_RTC()) {
 183                 int delta = get_rtcl() - (unsigned int) tstamp;
 184                 return delta < 0 ? delta + 1000000000 : delta;
 185         }
 186         return get_tbl() - tstamp;
 187 }
 188
 189 #define mulhwu(x,y) \
 190 ({unsigned z; asm ("mulhwu %0,%1,%2" : "=r" (z) : "r" (x), "r" (y)); z;})
 191
 192 #ifdef CONFIG_PPC64
 193 #define mulhdu(x,y) \
 194 ({unsigned long z; asm ("mulhdu %0,%1,%2" : "=r" (z) : "r" (x), "r" (y)); z;})
 195 #else
 196 extern u64 mulhdu(u64, u64);
 197 #endif
 198
 199 unsigned mulhwu_scale_factor(unsigned, unsigned);
 200 void div128_by_32(u64 dividend_high, u64 dividend_low,
 201                   unsigned divisor, struct div_result *dr);
 202
 203 /* Used to store Processor Utilization register (purr) values */
 204
 205 struct cpu_usage {
 206         u64 current_tb;  /* Holds the current purr register values */
 207 };
 208
 209 DECLARE_PER_CPU(struct cpu_usage, cpu_usage_array);
 210
 211 #endif /* __KERNEL__ */
 212 #endif /* __PPC64_TIME_H */