mirror of
https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git
synced 2024-08-21 08:19:28 +00:00
![Tony Breeds](/assets/img/avatar_default.png)
Currently iSeries will recalibrate the cputime_factors in the first settimeofday() call. It seems the reason for doing this is to ensure a resaonable time delta after time_init(). On current kernels (with udev), this call is made 40-60 seconds into the boot process, by moving it to a late initcall it is called approximately 5 seconds after time_init() is called. This is sufficient to recalibrate the timebase. Signed-off-by: Tony Breeds <tony@bakeyournoodle.com> CC: Stephen Rothwell <sfr@canb.auug.org.au> Signed-off-by: Paul Mackerras <paulus@samba.org>
246 lines
5.7 KiB
C
246 lines
5.7 KiB
C
/*
|
|
* 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 */
|