arch/powerpc/include/asm/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
  22 /* time.c */
  23 extern unsigned long tb_ticks_per_jiffy;
  24 extern unsigned long tb_ticks_per_usec;
  25 extern unsigned long tb_ticks_per_sec;
  26 extern struct clock_event_device decrementer_clockevent;
  27
  28 struct rtc_time;
  29 extern void to_tm(int tim, struct rtc_time * tm);
  30 extern void GregorianDay(struct rtc_time *tm);
  31
  32 extern void generic_calibrate_decr(void);
  33
  34 extern void set_dec_cpu6(unsigned int val);
  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_TB))
  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 #ifdef CONFIG_PPC64
 105 static inline u64 get_tb(void)
 106 {
 107         return mftb();
 108 }
 109 #else /* CONFIG_PPC64 */
 110 static inline u64 get_tb(void)
 111 {
 112         unsigned int tbhi, tblo, tbhi2;
 113
 114         do {
 115                 tbhi = get_tbu();
 116                 tblo = get_tbl();
 117                 tbhi2 = get_tbu();
 118         } while (tbhi != tbhi2);
 119
 120         return ((u64)tbhi << 32) | tblo;
 121 }
 122 #endif /* !CONFIG_PPC64 */
 123
 124 static inline u64 get_tb_or_rtc(void)
 125 {
 126         return __USE_RTC() ? get_rtc() : get_tb();
 127 }
 128
 129 static inline void set_tb(unsigned int upper, unsigned int lower)
 130 {
 131         mtspr(SPRN_TBWL, 0);
 132         mtspr(SPRN_TBWU, upper);
 133         mtspr(SPRN_TBWL, lower);
 134 }
 135
 136 /* Accessor functions for the decrementer register.
 137  * The 4xx doesn't even have a decrementer.  I tried to use the
 138  * generic timer interrupt code, which seems OK, with the 4xx PIT
 139  * in auto-reload mode.  The problem is PIT stops counting when it
 140  * hits zero.  If it would wrap, we could use it just like a decrementer.
 141  */
 142 static inline unsigned int get_dec(void)
 143 {
 144 #if defined(CONFIG_40x)
 145         return (mfspr(SPRN_PIT));
 146 #else
 147         return (mfspr(SPRN_DEC));
 148 #endif
 149 }
 150
 151 /*
 152  * Note: Book E and 4xx processors differ from other PowerPC processors
 153  * in when the decrementer generates its interrupt: on the 1 to 0
 154  * transition for Book E/4xx, but on the 0 to -1 transition for others.
 155  */
 156 static inline void set_dec(int val)
 157 {
 158 #if defined(CONFIG_40x)
 159         mtspr(SPRN_PIT, val);
 160 #elif defined(CONFIG_8xx_CPU6)
 161         set_dec_cpu6(val - 1);
 162 #else
 163 #ifndef CONFIG_BOOKE
 164         --val;
 165 #endif
 166         mtspr(SPRN_DEC, val);
 167 #endif /* not 40x or 8xx_CPU6 */
 168 }
 169
 170 static inline unsigned long tb_ticks_since(unsigned long tstamp)
 171 {
 172         if (__USE_RTC()) {
 173                 int delta = get_rtcl() - (unsigned int) tstamp;
 174                 return delta < 0 ? delta + 1000000000 : delta;
 175         }
 176         return get_tbl() - tstamp;
 177 }
 178
 179 #define mulhwu(x,y) \
 180 ({unsigned z; asm ("mulhwu %0,%1,%2" : "=r" (z) : "r" (x), "r" (y)); z;})
 181
 182 #ifdef CONFIG_PPC64
 183 #define mulhdu(x,y) \
 184 ({unsigned long z; asm ("mulhdu %0,%1,%2" : "=r" (z) : "r" (x), "r" (y)); z;})
 185 #else
 186 extern u64 mulhdu(u64, u64);
 187 #endif
 188
 189 extern void div128_by_32(u64 dividend_high, u64 dividend_low,
 190                          unsigned divisor, struct div_result *dr);
 191
 192 /* Used to store Processor Utilization register (purr) values */
 193
 194 struct cpu_usage {
 195         u64 current_tb;  /* Holds the current purr register values */
 196 };
 197
 198 DECLARE_PER_CPU(struct cpu_usage, cpu_usage_array);
 199
 200 extern void secondary_cpu_time_init(void);
 201
 202 DECLARE_PER_CPU(u64, decrementers_next_tb);
 203
 204 #endif /* __KERNEL__ */
 205 #endif /* __POWERPC_TIME_H */