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/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 extern unsigned long tb_last_stamp;
  34 extern u64 tb_last_jiffy;
  35
  36 DECLARE_PER_CPU(unsigned long, last_jiffy);
  37
  38 struct rtc_time;
  39 extern void to_tm(int tim, struct rtc_time * tm);
  40 extern time_t last_rtc_update;
  41
  42 extern void generic_calibrate_decr(void);
  43 extern void wakeup_decrementer(void);
  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 /* On ppc64 this gets us the whole timebase; on ppc32 just the lower half */
  85 static inline unsigned long get_tbl(void)
  86 {
  87         unsigned long tbl;
  88
  89 #if defined(CONFIG_403GCX)
  90         asm volatile("mfspr %0, 0x3dd" : "=r" (tbl));
  91 #else
  92         asm volatile("mftb %0" : "=r" (tbl));
  93 #endif
  94         return tbl;
  95 }
  96
  97 static inline unsigned int get_tbu(void)
  98 {
  99         unsigned int tbu;
 100
 101 #if defined(CONFIG_403GCX)
 102         asm volatile("mfspr %0, 0x3dc" : "=r" (tbu));
 103 #else
 104         asm volatile("mftbu %0" : "=r" (tbu));
 105 #endif
 106         return tbu;
 107 }
 108
 109 static inline unsigned int get_rtcl(void)
 110 {
 111         unsigned int rtcl;
 112
 113         asm volatile("mfrtcl %0" : "=r" (rtcl));
 114         return rtcl;
 115 }
 116
 117 static inline u64 get_rtc(void)
 118 {
 119         unsigned int hi, lo, hi2;
 120
 121         do {
 122                 asm volatile("mfrtcu %0; mfrtcl %1; mfrtcu %2"
 123                              : "=r" (hi), "=r" (lo), "=r" (hi2));
 124         } while (hi2 != hi);
 125         return (u64)hi * 1000000000 + lo;
 126 }
 127
 128 #ifdef CONFIG_PPC64
 129 static inline u64 get_tb(void)
 130 {
 131         return mftb();
 132 }
 133 #else
 134 static inline u64 get_tb(void)
 135 {
 136         unsigned int tbhi, tblo, tbhi2;
 137
 138         do {
 139                 tbhi = get_tbu();
 140                 tblo = get_tbl();
 141                 tbhi2 = get_tbu();
 142         } while (tbhi != tbhi2);
 143
 144         return ((u64)tbhi << 32) | tblo;
 145 }
 146 #endif
 147
 148 static inline void set_tb(unsigned int upper, unsigned int lower)
 149 {
 150         mtspr(SPRN_TBWL, 0);
 151         mtspr(SPRN_TBWU, upper);
 152         mtspr(SPRN_TBWL, lower);
 153 }
 154
 155 /* Accessor functions for the decrementer register.
 156  * The 4xx doesn't even have a decrementer.  I tried to use the
 157  * generic timer interrupt code, which seems OK, with the 4xx PIT
 158  * in auto-reload mode.  The problem is PIT stops counting when it
 159  * hits zero.  If it would wrap, we could use it just like a decrementer.
 160  */
 161 static inline unsigned int get_dec(void)
 162 {
 163 #if defined(CONFIG_40x)
 164         return (mfspr(SPRN_PIT));
 165 #else
 166         return (mfspr(SPRN_DEC));
 167 #endif
 168 }
 169
 170 static inline void set_dec(int val)
 171 {
 172 #if defined(CONFIG_40x)
 173         return;         /* Have to let it auto-reload */
 174 #elif defined(CONFIG_8xx_CPU6)
 175         set_dec_cpu6(val);
 176 #else
 177 #ifdef CONFIG_PPC_ISERIES
 178         int cur_dec;
 179
 180         if (get_lppaca()->shared_proc) {
 181                 get_lppaca()->virtual_decr = val;
 182                 cur_dec = get_dec();
 183                 if (cur_dec > val)
 184                         HvCall_setVirtualDecr();
 185         } else
 186 #endif
 187                 mtspr(SPRN_DEC, val);
 188 #endif /* not 40x or 8xx_CPU6 */
 189 }
 190
 191 static inline unsigned long tb_ticks_since(unsigned long tstamp)
 192 {
 193         if (__USE_RTC()) {
 194                 int delta = get_rtcl() - (unsigned int) tstamp;
 195                 return delta < 0 ? delta + 1000000000 : delta;
 196         }
 197         return get_tbl() - tstamp;
 198 }
 199
 200 #define mulhwu(x,y) \
 201 ({unsigned z; asm ("mulhwu %0,%1,%2" : "=r" (z) : "r" (x), "r" (y)); z;})
 202
 203 #ifdef CONFIG_PPC64
 204 #define mulhdu(x,y) \
 205 ({unsigned long z; asm ("mulhdu %0,%1,%2" : "=r" (z) : "r" (x), "r" (y)); z;})
 206 #else
 207 extern u64 mulhdu(u64, u64);
 208 #endif
 209
 210 extern void smp_space_timers(unsigned int);
 211
 212 extern unsigned mulhwu_scale_factor(unsigned, unsigned);
 213 extern void div128_by_32(u64 dividend_high, u64 dividend_low,
 214                          unsigned divisor, struct div_result *dr);
 215
 216 /* Used to store Processor Utilization register (purr) values */
 217
 218 struct cpu_usage {
 219         u64 current_tb;  /* Holds the current purr register values */
 220 };
 221
 222 DECLARE_PER_CPU(struct cpu_usage, cpu_usage_array);
 223
 224 #endif /* __KERNEL__ */
 225 #endif /* __PPC64_TIME_H */