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Diffstat (limited to 'arch/s390/include/asm/timex.h')
-rw-r--r-- | arch/s390/include/asm/timex.h | 257 |
1 files changed, 257 insertions, 0 deletions
diff --git a/arch/s390/include/asm/timex.h b/arch/s390/include/asm/timex.h new file mode 100644 index 000000000..99a7e0282 --- /dev/null +++ b/arch/s390/include/asm/timex.h @@ -0,0 +1,257 @@ +/* SPDX-License-Identifier: GPL-2.0 */ +/* + * 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 <linux/preempt.h> +#include <linux/time64.h> +#include <asm/lowcore.h> + +/* The value of the TOD clock for 1.1.1970. */ +#define TOD_UNIX_EPOCH 0x7d91048bca000000ULL + +extern u64 clock_comparator_max; + +/* 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 time_early_init(void); + +extern unsigned char ptff_function_mask[16]; + +/* 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_QUI 0x04 /* query UTC 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; +} + +/* Query UTC information result */ +struct ptff_qui { + unsigned int tm : 2; + unsigned int ts : 2; + unsigned int : 28; + unsigned int pad_0x04; + unsigned long leap_event; + short old_leap; + short new_leap; + unsigned int pad_0x14; + unsigned long prt[5]; + unsigned long cst[3]; + unsigned int skew; + unsigned int pad_0x5c[41]; +} __packed; + +/* + * ptff - Perform timing facility function + * @ptff_block: Pointer to ptff parameter block + * @len: Length of parameter block + * @func: Function code + * Returns: Condition code (0 on success) + */ +#define ptff(ptff_block, len, func) \ +({ \ + struct addrtype { char _[len]; }; \ + 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" (*(struct addrtype *) reg1) \ + : "d" (reg0), "d" (reg1) : "cc"); \ + rc; \ +}) + +static inline unsigned long long local_tick_disable(void) +{ + unsigned long long old; + + old = S390_lowcore.clock_comparator; + S390_lowcore.clock_comparator = clock_comparator_max; + 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; +} +#define get_cycles get_cycles + +int get_phys_clock(unsigned long *clock); +void init_cpu_timer(void); +unsigned long long monotonic_clock(void); + +extern unsigned char tod_clock_base[16] __aligned(8); + +/** + * get_clock_monotonic - returns current time in clock rate units + * + * The clock and tod_clock_base get changed via stop_machine. + * Therefore preemption must be disabled, otherwise the returned + * value is not guaranteed to be monotonic. + */ +static inline unsigned long long get_tod_clock_monotonic(void) +{ + unsigned long long tod; + + preempt_disable_notrace(); + tod = get_tod_clock() - *(unsigned long long *) &tod_clock_base[1]; + preempt_enable_notrace(); + return tod; +} + +/** + * 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 == 2^9 * th + tl (th upper 55 bits, tl lower 9 bits) + * we end up with + * + * ns = ((2^9 * th + tl) * 125 ) >> 9; + * -> ns = (th * 125) + ((tl * 125) >> 9); + * + */ +static inline unsigned long long tod_to_ns(unsigned long long todval) +{ + return ((todval >> 9) * 125) + (((todval & 0x1ff) * 125) >> 9); +} + +/** + * tod_after - compare two 64 bit TOD values + * @a: first 64 bit TOD timestamp + * @b: second 64 bit TOD timestamp + * + * Returns: true if a is later than b + */ +static inline int tod_after(unsigned long long a, unsigned long long b) +{ + if (MACHINE_HAS_SCC) + return (long long) a > (long long) b; + return a > b; +} + +/** + * tod_after_eq - compare two 64 bit TOD values + * @a: first 64 bit TOD timestamp + * @b: second 64 bit TOD timestamp + * + * Returns: true if a is later than b + */ +static inline int tod_after_eq(unsigned long long a, unsigned long long b) +{ + if (MACHINE_HAS_SCC) + return (long long) a >= (long long) b; + return a >= b; +} + +#endif |