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/*
* S390 version
* Copyright IBM Corp. 1999
*
* Derived from "include/asm-i386/timex.h"
* Copyright (C) 1992, Linus Torvalds
*/
#ifndef _ASM_S390_TIMEX_H
#define _ASM_S390_TIMEX_H
#include <asm/lowcore.h>
#include <linux/time64.h>
/* The value of the TOD clock for 1.1.1970. */
#define TOD_UNIX_EPOCH 0x7d91048bca000000ULL
/* Inline functions for clock register access. */
static inline int set_tod_clock(__u64 time)
{
int cc;
asm volatile(
" sck %1\n"
" ipm %0\n"
" srl %0,28\n"
: "=d" (cc) : "Q" (time) : "cc");
return cc;
}
static inline int store_tod_clock(__u64 *time)
{
int cc;
asm volatile(
" stck %1\n"
" ipm %0\n"
" srl %0,28\n"
: "=d" (cc), "=Q" (*time) : : "cc");
return cc;
}
static inline void set_clock_comparator(__u64 time)
{
asm volatile("sckc %0" : : "Q" (time));
}
static inline void store_clock_comparator(__u64 *time)
{
asm volatile("stckc %0" : "=Q" (*time));
}
void clock_comparator_work(void);
void __init ptff_init(void);
extern unsigned char ptff_function_mask[16];
extern unsigned long lpar_offset;
/* Function codes for the ptff instruction. */
#define PTFF_QAF 0x00 /* query available functions */
#define PTFF_QTO 0x01 /* query tod offset */
#define PTFF_QSI 0x02 /* query steering information */
#define PTFF_ATO 0x40 /* adjust tod offset */
#define PTFF_STO 0x41 /* set tod offset */
#define PTFF_SFS 0x42 /* set fine steering rate */
#define PTFF_SGS 0x43 /* set gross steering rate */
/* Query TOD offset result */
struct ptff_qto {
unsigned long long physical_clock;
unsigned long long tod_offset;
unsigned long long logical_tod_offset;
unsigned long long tod_epoch_difference;
} __packed;
static inline int ptff_query(unsigned int nr)
{
unsigned char *ptr;
ptr = ptff_function_mask + (nr >> 3);
return (*ptr & (0x80 >> (nr & 7))) != 0;
}
static inline int ptff(void *ptff_block, size_t len, unsigned int func)
{
typedef struct { char _[len]; } addrtype;
register unsigned int reg0 asm("0") = func;
register unsigned long reg1 asm("1") = (unsigned long) ptff_block;
int rc;
asm volatile(
" .word 0x0104\n"
" ipm %0\n"
" srl %0,28\n"
: "=d" (rc), "+m" (*(addrtype *) ptff_block)
: "d" (reg0), "d" (reg1) : "cc");
return rc;
}
static inline unsigned long long local_tick_disable(void)
{
unsigned long long old;
old = S390_lowcore.clock_comparator;
S390_lowcore.clock_comparator = -1ULL;
set_clock_comparator(S390_lowcore.clock_comparator);
return old;
}
static inline void local_tick_enable(unsigned long long comp)
{
S390_lowcore.clock_comparator = comp;
set_clock_comparator(S390_lowcore.clock_comparator);
}
#define CLOCK_TICK_RATE 1193180 /* Underlying HZ */
#define STORE_CLOCK_EXT_SIZE 16 /* stcke writes 16 bytes */
typedef unsigned long long cycles_t;
static inline void get_tod_clock_ext(char *clk)
{
typedef struct { char _[STORE_CLOCK_EXT_SIZE]; } addrtype;
asm volatile("stcke %0" : "=Q" (*(addrtype *) clk) : : "cc");
}
static inline unsigned long long get_tod_clock(void)
{
char clk[STORE_CLOCK_EXT_SIZE];
get_tod_clock_ext(clk);
return *((unsigned long long *)&clk[1]);
}
static inline unsigned long long get_tod_clock_fast(void)
{
#ifdef CONFIG_HAVE_MARCH_Z9_109_FEATURES
unsigned long long clk;
asm volatile("stckf %0" : "=Q" (clk) : : "cc");
return clk;
#else
return get_tod_clock();
#endif
}
static inline cycles_t get_cycles(void)
{
return (cycles_t) get_tod_clock() >> 2;
}
int get_phys_clock(unsigned long long *clock);
void init_cpu_timer(void);
unsigned long long monotonic_clock(void);
void tod_to_timeval(__u64 todval, struct timespec64 *xt);
static inline
void stck_to_timespec64(unsigned long long stck, struct timespec64 *ts)
{
tod_to_timeval(stck - TOD_UNIX_EPOCH, ts);
}
extern u64 sched_clock_base_cc;
/**
* get_clock_monotonic - returns current time in clock rate units
*
* The caller must ensure that preemption is disabled.
* The clock and sched_clock_base get changed via stop_machine.
* Therefore preemption must be disabled when calling this
* function, otherwise the returned value is not guaranteed to
* be monotonic.
*/
static inline unsigned long long get_tod_clock_monotonic(void)
{
return get_tod_clock() - sched_clock_base_cc;
}
/**
* tod_to_ns - convert a TOD format value to nanoseconds
* @todval: to be converted TOD format value
* Returns: number of nanoseconds that correspond to the TOD format value
*
* Converting a 64 Bit TOD format value to nanoseconds means that the value
* must be divided by 4.096. In order to achieve that we multiply with 125
* and divide by 512:
*
* ns = (todval * 125) >> 9;
*
* In order to avoid an overflow with the multiplication we can rewrite this.
* With a split todval == 2^32 * th + tl (th upper 32 bits, tl lower 32 bits)
* we end up with
*
* ns = ((2^32 * th + tl) * 125 ) >> 9;
* -> ns = (2^23 * th * 125) + ((tl * 125) >> 9);
*
*/
static inline unsigned long long tod_to_ns(unsigned long long todval)
{
unsigned long long ns;
ns = ((todval >> 32) << 23) * 125;
ns += ((todval & 0xffffffff) * 125) >> 9;
return ns;
}
#endif
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