release/src-rt-6.x.4708/linux/linux-2.6.36/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 #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
  32 struct rtc_time;
  33 extern void to_tm(int tim, struct rtc_time * tm);
  34 extern void GregorianDay(struct rtc_time *tm);
  35
  36 extern void generic_calibrate_decr(void);
  37 extern void snapshot_timebase(void);
  38
  39 extern void set_dec_cpu6(unsigned int val);
  40
  41 /* Some sane defaults: 125 MHz timebase, 1GHz processor */
  42 extern unsigned long ppc_proc_freq;
  43 #define DEFAULT_PROC_FREQ       (DEFAULT_TB_FREQ * 8)
  44 extern unsigned long ppc_tb_freq;
  45 #define DEFAULT_TB_FREQ         125000000UL
  46
  47 struct div_result {
  48         u64 result_high;
  49         u64 result_low;
  50 };
  51
  52 /* Accessor functions for the timebase (RTC on 601) registers. */
  53 /* If one day CONFIG_POWER is added just define __USE_RTC as 1 */
  54 #ifdef CONFIG_6xx
  55 #define __USE_RTC()     (!cpu_has_feature(CPU_FTR_USE_TB))
  56 #else
  57 #define __USE_RTC()     0
  58 #endif
  59
  60 #ifdef CONFIG_PPC64
  61
  62 /* For compatibility, get_tbl() is defined as get_tb() on ppc64 */
  63 #define get_tbl         get_tb
  64
  65 #else
  66
  67 static inline unsigned long get_tbl(void)
  68 {
  69 #if defined(CONFIG_403GCX)
  70         unsigned long tbl;
  71         asm volatile("mfspr %0, 0x3dd" : "=r" (tbl));
  72         return tbl;
  73 #else
  74         return mftbl();
  75 #endif
  76 }
  77
  78 static inline unsigned int get_tbu(void)
  79 {
  80 #ifdef CONFIG_403GCX
  81         unsigned int tbu;
  82         asm volatile("mfspr %0, 0x3dc" : "=r" (tbu));
  83         return tbu;
  84 #else
  85         return mftbu();
  86 #endif
  87 }
  88 #endif /* !CONFIG_PPC64 */
  89
  90 static inline unsigned int get_rtcl(void)
  91 {
  92         unsigned int rtcl;
  93
  94         asm volatile("mfrtcl %0" : "=r" (rtcl));
  95         return rtcl;
  96 }
  97
  98 static inline u64 get_rtc(void)
  99 {
 100         unsigned int hi, lo, hi2;
 101
 102         do {
 103                 asm volatile("mfrtcu %0; mfrtcl %1; mfrtcu %2"
 104                              : "=r" (hi), "=r" (lo), "=r" (hi2));
 105         } while (hi2 != hi);
 106         return (u64)hi * 1000000000 + lo;
 107 }
 108
 109 #ifdef CONFIG_PPC64
 110 static inline u64 get_tb(void)
 111 {
 112         return mftb();
 113 }
 114 #else /* CONFIG_PPC64 */
 115 static inline u64 get_tb(void)
 116 {
 117         unsigned int tbhi, tblo, tbhi2;
 118
 119         do {
 120                 tbhi = get_tbu();
 121                 tblo = get_tbl();
 122                 tbhi2 = get_tbu();
 123         } while (tbhi != tbhi2);
 124
 125         return ((u64)tbhi << 32) | tblo;
 126 }
 127 #endif /* !CONFIG_PPC64 */
 128
 129 static inline u64 get_tb_or_rtc(void)
 130 {
 131         return __USE_RTC() ? get_rtc() : get_tb();
 132 }
 133
 134 static inline void set_tb(unsigned int upper, unsigned int lower)
 135 {
 136         mtspr(SPRN_TBWL, 0);
 137         mtspr(SPRN_TBWU, upper);
 138         mtspr(SPRN_TBWL, lower);
 139 }
 140
 141 /* Accessor functions for the decrementer register.
 142  * The 4xx doesn't even have a decrementer.  I tried to use the
 143  * generic timer interrupt code, which seems OK, with the 4xx PIT
 144  * in auto-reload mode.  The problem is PIT stops counting when it
 145  * hits zero.  If it would wrap, we could use it just like a decrementer.
 146  */
 147 static inline unsigned int get_dec(void)
 148 {
 149 #if defined(CONFIG_40x)
 150         return (mfspr(SPRN_PIT));
 151 #else
 152         return (mfspr(SPRN_DEC));
 153 #endif
 154 }
 155
 156 /*
 157  * Note: Book E and 4xx processors differ from other PowerPC processors
 158  * in when the decrementer generates its interrupt: on the 1 to 0
 159  * transition for Book E/4xx, but on the 0 to -1 transition for others.
 160  */
 161 static inline void set_dec(int val)
 162 {
 163 #if defined(CONFIG_40x)
 164         mtspr(SPRN_PIT, val);
 165 #elif defined(CONFIG_8xx_CPU6)
 166         set_dec_cpu6(val - 1);
 167 #else
 168 #ifndef CONFIG_BOOKE
 169         --val;
 170 #endif
 171 #ifdef CONFIG_PPC_ISERIES
 172         if (firmware_has_feature(FW_FEATURE_ISERIES) &&
 173                         get_lppaca()->shared_proc) {
 174                 get_lppaca()->virtual_decr = val;
 175                 if (get_dec() > val)
 176                         HvCall_setVirtualDecr();
 177                 return;
 178         }
 179 #endif
 180         mtspr(SPRN_DEC, val);
 181 #endif /* not 40x or 8xx_CPU6 */
 182 }
 183
 184 static inline unsigned long tb_ticks_since(unsigned long tstamp)
 185 {
 186         if (__USE_RTC()) {
 187                 int delta = get_rtcl() - (unsigned int) tstamp;
 188                 return delta < 0 ? delta + 1000000000 : delta;
 189         }
 190         return get_tbl() - tstamp;
 191 }
 192
 193 #define mulhwu(x,y) \
 194 ({unsigned z; asm ("mulhwu %0,%1,%2" : "=r" (z) : "r" (x), "r" (y)); z;})
 195
 196 #ifdef CONFIG_PPC64
 197 #define mulhdu(x,y) \
 198 ({unsigned long z; asm ("mulhdu %0,%1,%2" : "=r" (z) : "r" (x), "r" (y)); z;})
 199 #else
 200 extern u64 mulhdu(u64, u64);
 201 #endif
 202
 203 extern void div128_by_32(u64 dividend_high, u64 dividend_low,
 204                          unsigned divisor, struct div_result *dr);
 205
 206 /* Used to store Processor Utilization register (purr) values */
 207
 208 struct cpu_usage {
 209         u64 current_tb;  /* Holds the current purr register values */
 210 };
 211
 212 DECLARE_PER_CPU(struct cpu_usage, cpu_usage_array);
 213
 214 #if defined(CONFIG_VIRT_CPU_ACCOUNTING)
 215 extern void calculate_steal_time(void);
 216 extern void snapshot_timebases(void);
 217 #define account_process_vtime(tsk)              account_process_tick(tsk, 0)
 218 #else
 219 #define calculate_steal_time()                  do { } while (0)
 220 #define snapshot_timebases()                    do { } while (0)
 221 #define account_process_vtime(tsk)              do { } while (0)
 222 #endif
 223
 224 extern void secondary_cpu_time_init(void);
 225 extern void iSeries_time_init_early(void);
 226
 227 #endif /* __KERNEL__ */
 228 #endif /* __POWERPC_TIME_H */