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/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 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 extern void snapshot_timebase(void);
  45
  46 /* Some sane defaults: 125 MHz timebase, 1GHz processor */
  47 extern unsigned long ppc_proc_freq;
  48 #define DEFAULT_PROC_FREQ       (DEFAULT_TB_FREQ * 8)
  49 extern unsigned long ppc_tb_freq;
  50 #define DEFAULT_TB_FREQ         125000000UL
  51
  52 /*
  53  * By putting all of this stuff into a single struct we
  54  * reduce the number of cache lines touched by do_gettimeofday.
  55  * Both by collecting all of the data in one cache line and
  56  * by touching only one TOC entry on ppc64.
  57  */
  58 struct gettimeofday_vars {
  59         u64 tb_to_xs;
  60         u64 stamp_xsec;
  61         u64 tb_orig_stamp;
  62 };
  63
  64 struct gettimeofday_struct {
  65         unsigned long tb_ticks_per_sec;
  66         struct gettimeofday_vars vars[2];
  67         struct gettimeofday_vars * volatile varp;
  68         unsigned      var_idx;
  69         unsigned      tb_to_us;
  70 };
  71
  72 struct div_result {
  73         u64 result_high;
  74         u64 result_low;
  75 };
  76
  77 /* Accessor functions for the timebase (RTC on 601) registers. */
  78 /* If one day CONFIG_POWER is added just define __USE_RTC as 1 */
  79 #ifdef CONFIG_6xx
  80 #define __USE_RTC()     (!cpu_has_feature(CPU_FTR_USE_TB))
  81 #else
  82 #define __USE_RTC()     0
  83 #endif
  84
  85 /* On ppc64 this gets us the whole timebase; on ppc32 just the lower half */
  86 static inline unsigned long get_tbl(void)
  87 {
  88         unsigned long tbl;
  89
  90 #if defined(CONFIG_403GCX)
  91         asm volatile("mfspr %0, 0x3dd" : "=r" (tbl));
  92 #else
  93         asm volatile("mftb %0" : "=r" (tbl));
  94 #endif
  95         return tbl;
  96 }
  97
  98 static inline unsigned int get_tbu(void)
  99 {
 100         unsigned int tbu;
 101
 102 #if defined(CONFIG_403GCX)
 103         asm volatile("mfspr %0, 0x3dc" : "=r" (tbu));
 104 #else
 105         asm volatile("mftbu %0" : "=r" (tbu));
 106 #endif
 107         return tbu;
 108 }
 109
 110 static inline unsigned int get_rtcl(void)
 111 {
 112         unsigned int rtcl;
 113
 114         asm volatile("mfrtcl %0" : "=r" (rtcl));
 115         return rtcl;
 116 }
 117
 118 static inline u64 get_rtc(void)
 119 {
 120         unsigned int hi, lo, hi2;
 121
 122         do {
 123                 asm volatile("mfrtcu %0; mfrtcl %1; mfrtcu %2"
 124                              : "=r" (hi), "=r" (lo), "=r" (hi2));
 125         } while (hi2 != hi);
 126         return (u64)hi * 1000000000 + lo;
 127 }
 128
 129 #ifdef CONFIG_PPC64
 130 static inline u64 get_tb(void)
 131 {
 132         return mftb();
 133 }
 134 #else
 135 static inline u64 get_tb(void)
 136 {
 137         unsigned int tbhi, tblo, tbhi2;
 138
 139         do {
 140                 tbhi = get_tbu();
 141                 tblo = get_tbl();
 142                 tbhi2 = get_tbu();
 143         } while (tbhi != tbhi2);
 144
 145         return ((u64)tbhi << 32) | tblo;
 146 }
 147 #endif
 148
 149 static inline void set_tb(unsigned int upper, unsigned int lower)
 150 {
 151         mtspr(SPRN_TBWL, 0);
 152         mtspr(SPRN_TBWU, upper);
 153         mtspr(SPRN_TBWL, lower);
 154 }
 155
 156 /* Accessor functions for the decrementer register.
 157  * The 4xx doesn't even have a decrementer.  I tried to use the
 158  * generic timer interrupt code, which seems OK, with the 4xx PIT
 159  * in auto-reload mode.  The problem is PIT stops counting when it
 160  * hits zero.  If it would wrap, we could use it just like a decrementer.
 161  */
 162 static inline unsigned int get_dec(void)
 163 {
 164 #if defined(CONFIG_40x)
 165         return (mfspr(SPRN_PIT));
 166 #else
 167         return (mfspr(SPRN_DEC));
 168 #endif
 169 }
 170
 171 static inline void set_dec(int val)
 172 {
 173 #if defined(CONFIG_40x)
 174         return;         /* Have to let it auto-reload */
 175 #elif defined(CONFIG_8xx_CPU6)
 176         set_dec_cpu6(val);
 177 #else
 178 #ifdef CONFIG_PPC_ISERIES
 179         int cur_dec;
 180
 181         if (firmware_has_feature(FW_FEATURE_ISERIES) &&
 182                         get_lppaca()->shared_proc) {
 183                 get_lppaca()->virtual_decr = val;
 184                 cur_dec = get_dec();
 185                 if (cur_dec > val)
 186                         HvCall_setVirtualDecr();
 187         } else
 188 #endif
 189                 mtspr(SPRN_DEC, val);
 190 #endif /* not 40x or 8xx_CPU6 */
 191 }
 192
 193 static inline unsigned long tb_ticks_since(unsigned long tstamp)
 194 {
 195         if (__USE_RTC()) {
 196                 int delta = get_rtcl() - (unsigned int) tstamp;
 197                 return delta < 0 ? delta + 1000000000 : delta;
 198         }
 199         return get_tbl() - tstamp;
 200 }
 201
 202 #define mulhwu(x,y) \
 203 ({unsigned z; asm ("mulhwu %0,%1,%2" : "=r" (z) : "r" (x), "r" (y)); z;})
 204
 205 #ifdef CONFIG_PPC64
 206 #define mulhdu(x,y) \
 207 ({unsigned long z; asm ("mulhdu %0,%1,%2" : "=r" (z) : "r" (x), "r" (y)); z;})
 208 #else
 209 extern u64 mulhdu(u64, u64);
 210 #endif
 211
 212 extern void smp_space_timers(unsigned int);
 213
 214 extern unsigned mulhwu_scale_factor(unsigned, unsigned);
 215 extern void div128_by_32(u64 dividend_high, u64 dividend_low,
 216                          unsigned divisor, struct div_result *dr);
 217
 218 /* Used to store Processor Utilization register (purr) values */
 219
 220 struct cpu_usage {
 221         u64 current_tb;  /* Holds the current purr register values */
 222 };
 223
 224 DECLARE_PER_CPU(struct cpu_usage, cpu_usage_array);
 225
 226 #ifdef CONFIG_VIRT_CPU_ACCOUNTING
 227 extern void account_process_vtime(struct task_struct *tsk);
 228 #else
 229 #define account_process_vtime(tsk)              do { } while (0)
 230 #endif
 231
 232 #if defined(CONFIG_VIRT_CPU_ACCOUNTING) && defined(CONFIG_PPC_SPLPAR)
 233 extern void calculate_steal_time(void);
 234 extern void snapshot_timebases(void);
 235 #else
 236 #define calculate_steal_time()                  do { } while (0)
 237 #define snapshot_timebases()                    do { } while (0)
 238 #endif
 239
 240 #endif /* __KERNEL__ */
 241 #endif /* __PPC64_TIME_H */