/*
   * Common time prototypes and such for all ppc machines.
   *
   * Written by Cort Dougan (cort@cs.nmt.edu) to merge
   * Paul Mackerras' version and mine for PReP and Pmac.
   *
   * This program is free software; you can redistribute it and/or
   * modify it under the terms of the GNU General Public License
   * as published by the Free Software Foundation; either version
   * 2 of the License, or (at your option) any later version.
   */
  
  #ifndef __POWERPC_TIME_H
  #define __POWERPC_TIME_H
  
  #ifdef __KERNEL__

  #include <linux/types.h>
  #include <linux/percpu.h>
  
  #include <asm/processor.h>

  #ifdef CONFIG_PPC_ISERIES

  #include <asm/paca.h>

  #include <asm/firmware.h>

  #include <asm/iseries/hv_call.h>

  #endif
  
  /* time.c */
  extern unsigned long tb_ticks_per_jiffy;
  extern unsigned long tb_ticks_per_usec;
  extern unsigned long tb_ticks_per_sec;
  extern u64 tb_to_xs;
  extern unsigned      tb_to_us;

  
  struct rtc_time;
  extern void to_tm(int tim, struct rtc_time * tm);
  extern time_t last_rtc_update;
  
  extern void generic_calibrate_decr(void);
  extern void wakeup_decrementer(void);

  extern void snapshot_timebase(void);

  extern void set_dec_cpu6(unsigned int val);

  /* Some sane defaults: 125 MHz timebase, 1GHz processor */
  extern unsigned long ppc_proc_freq;
  #define DEFAULT_PROC_FREQ	(DEFAULT_TB_FREQ * 8)
  extern unsigned long ppc_tb_freq;
  #define DEFAULT_TB_FREQ		125000000UL
  
  /*
   * By putting all of this stuff into a single struct we 
   * reduce the number of cache lines touched by do_gettimeofday.
   * Both by collecting all of the data in one cache line and
   * by touching only one TOC entry on ppc64.
   */
  struct gettimeofday_vars {
  	u64 tb_to_xs;
  	u64 stamp_xsec;
  	u64 tb_orig_stamp;
  };
  
  struct gettimeofday_struct {
  	unsigned long tb_ticks_per_sec;
  	struct gettimeofday_vars vars[2];
  	struct gettimeofday_vars * volatile varp;
  	unsigned      var_idx;
  	unsigned      tb_to_us;
  };
  
  struct div_result {
  	u64 result_high;
  	u64 result_low;
  };
  
  /* Accessor functions for the timebase (RTC on 601) registers. */
  /* If one day CONFIG_POWER is added just define __USE_RTC as 1 */
  #ifdef CONFIG_6xx

  #define __USE_RTC()	(!cpu_has_feature(CPU_FTR_USE_TB))

  #else
  #define __USE_RTC()	0
  #endif

  #ifdef CONFIG_PPC64
  
  /* For compatibility, get_tbl() is defined as get_tb() on ppc64 */
  #define get_tbl		get_tb
  
  #else

  static inline unsigned long get_tbl(void)
  {

  #if defined(CONFIG_403GCX)

  	unsigned long tbl;

  	asm volatile("mfspr %0, 0x3dd" : "=r" (tbl));

  	return tbl;

  #else

  	return mftbl();

  #endif

  }
  
  static inline unsigned int get_tbu(void)
  {

  #ifdef CONFIG_403GCX

  	unsigned int tbu;

  	asm volatile("mfspr %0, 0x3dc" : "=r" (tbu));

  	return tbu;

  #else

  	return mftbu();

  #endif

  }

  #endif /* !CONFIG_PPC64 */

  
  static inline unsigned int get_rtcl(void)
  {
  	unsigned int rtcl;
  
  	asm volatile("mfrtcl %0" : "=r" (rtcl));
  	return rtcl;
  }

  static inline u64 get_rtc(void)
  {
  	unsigned int hi, lo, hi2;
  
  	do {
  		asm volatile("mfrtcu %0; mfrtcl %1; mfrtcu %2"
  			     : "=r" (hi), "=r" (lo), "=r" (hi2));
  	} while (hi2 != hi);
  	return (u64)hi * 1000000000 + lo;
  }

  #ifdef CONFIG_PPC64
  static inline u64 get_tb(void)
  {
  	return mftb();
  }

  #else /* CONFIG_PPC64 */

  static inline u64 get_tb(void)
  {
  	unsigned int tbhi, tblo, tbhi2;
  
  	do {
  		tbhi = get_tbu();
  		tblo = get_tbl();
  		tbhi2 = get_tbu();
  	} while (tbhi != tbhi2);
  
  	return ((u64)tbhi << 32) | tblo;
  }

  #endif /* !CONFIG_PPC64 */

  
  static inline void set_tb(unsigned int upper, unsigned int lower)
  {
  	mtspr(SPRN_TBWL, 0);
  	mtspr(SPRN_TBWU, upper);
  	mtspr(SPRN_TBWL, lower);
  }
  
  /* Accessor functions for the decrementer register.
   * The 4xx doesn't even have a decrementer.  I tried to use the
   * generic timer interrupt code, which seems OK, with the 4xx PIT
   * in auto-reload mode.  The problem is PIT stops counting when it
   * hits zero.  If it would wrap, we could use it just like a decrementer.
   */
  static inline unsigned int get_dec(void)
  {
  #if defined(CONFIG_40x)
  	return (mfspr(SPRN_PIT));
  #else
  	return (mfspr(SPRN_DEC));
  #endif
  }
  
  static inline void set_dec(int val)
  {
  #if defined(CONFIG_40x)
  	return;		/* Have to let it auto-reload */
  #elif defined(CONFIG_8xx_CPU6)
  	set_dec_cpu6(val);
  #else
  #ifdef CONFIG_PPC_ISERIES

  	int cur_dec;

  	if (firmware_has_feature(FW_FEATURE_ISERIES) &&
  			get_lppaca()->shared_proc) {

  		get_lppaca()->virtual_decr = val;

  		cur_dec = get_dec();
  		if (cur_dec > val)
  			HvCall_setVirtualDecr();
  	} else
  #endif
  		mtspr(SPRN_DEC, val);
  #endif /* not 40x or 8xx_CPU6 */
  }
  
  static inline unsigned long tb_ticks_since(unsigned long tstamp)
  {
  	if (__USE_RTC()) {
  		int delta = get_rtcl() - (unsigned int) tstamp;
  		return delta < 0 ? delta + 1000000000 : delta;
  	}
  	return get_tbl() - tstamp;
  }
  
  #define mulhwu(x,y) \
  ({unsigned z; asm ("mulhwu %0,%1,%2" : "=r" (z) : "r" (x), "r" (y)); z;})
  
  #ifdef CONFIG_PPC64
  #define mulhdu(x,y) \
  ({unsigned long z; asm ("mulhdu %0,%1,%2" : "=r" (z) : "r" (x), "r" (y)); z;})
  #else
  extern u64 mulhdu(u64, u64);
  #endif

  extern void smp_space_timers(unsigned int);
  
  extern unsigned mulhwu_scale_factor(unsigned, unsigned);
  extern void div128_by_32(u64 dividend_high, u64 dividend_low,
  			 unsigned divisor, struct div_result *dr);

  
  /* Used to store Processor Utilization register (purr) values */
  
  struct cpu_usage {
          u64 current_tb;  /* Holds the current purr register values */
  };
  
  DECLARE_PER_CPU(struct cpu_usage, cpu_usage_array);

  #ifdef CONFIG_VIRT_CPU_ACCOUNTING
  extern void account_process_vtime(struct task_struct *tsk);
  #else
  #define account_process_vtime(tsk)		do { } while (0)
  #endif

  #if defined(CONFIG_VIRT_CPU_ACCOUNTING)

  extern void calculate_steal_time(void);
  extern void snapshot_timebases(void);
  #else
  #define calculate_steal_time()			do { } while (0)
  #define snapshot_timebases()			do { } while (0)
  #endif

  extern void iSeries_time_init_early(void);

  #endif /* __KERNEL__ */

  #endif /* __POWERPC_TIME_H */