arch/s390/include/asm/timex.h

   1 /*
   2  *  S390 version
   3  *    Copyright IBM Corp. 1999
   4  *
   5  *  Derived from "include/asm-i386/timex.h"
   6  *    Copyright (C) 1992, Linus Torvalds
   7  */
   8
   9 #ifndef _ASM_S390_TIMEX_H
  10 #define _ASM_S390_TIMEX_H
  11
  12 #include <asm/lowcore.h>
  13 #include <linux/time64.h>
  14
  15 /* The value of the TOD clock for 1.1.1970. */
  16 #define TOD_UNIX_EPOCH 0x7d91048bca000000ULL
  17
  18 /* Inline functions for clock register access. */
  19 static inline int set_tod_clock(__u64 time)
  20 {
  21         int cc;
  22
  23         asm volatile(
  24                 "   sck   %1\n"
  25                 "   ipm   %0\n"
  26                 "   srl   %0,28\n"
  27                 : "=d" (cc) : "Q" (time) : "cc");
  28         return cc;
  29 }
  30
  31 static inline int store_tod_clock(__u64 *time)
  32 {
  33         int cc;
  34
  35         asm volatile(
  36                 "   stck  %1\n"
  37                 "   ipm   %0\n"
  38                 "   srl   %0,28\n"
  39                 : "=d" (cc), "=Q" (*time) : : "cc");
  40         return cc;
  41 }
  42
  43 static inline void set_clock_comparator(__u64 time)
  44 {
  45         asm volatile("sckc %0" : : "Q" (time));
  46 }
  47
  48 static inline void store_clock_comparator(__u64 *time)
  49 {
  50         asm volatile("stckc %0" : "=Q" (*time));
  51 }
  52
  53 void clock_comparator_work(void);
  54
  55 void __init ptff_init(void);
  56
  57 extern unsigned char ptff_function_mask[16];
  58 extern unsigned long lpar_offset;
  59 extern unsigned long initial_leap_seconds;
  60
  61 /* Function codes for the ptff instruction. */
  62 #define PTFF_QAF        0x00    /* query available functions */
  63 #define PTFF_QTO        0x01    /* query tod offset */
  64 #define PTFF_QSI        0x02    /* query steering information */
  65 #define PTFF_QUI        0x04    /* query UTC information */
  66 #define PTFF_ATO        0x40    /* adjust tod offset */
  67 #define PTFF_STO        0x41    /* set tod offset */
  68 #define PTFF_SFS        0x42    /* set fine steering rate */
  69 #define PTFF_SGS        0x43    /* set gross steering rate */
  70
  71 /* Query TOD offset result */
  72 struct ptff_qto {
  73         unsigned long long physical_clock;
  74         unsigned long long tod_offset;
  75         unsigned long long logical_tod_offset;
  76         unsigned long long tod_epoch_difference;
  77 } __packed;
  78
  79 static inline int ptff_query(unsigned int nr)
  80 {
  81         unsigned char *ptr;
  82
  83         ptr = ptff_function_mask + (nr >> 3);
  84         return (*ptr & (0x80 >> (nr & 7))) != 0;
  85 }
  86
  87 /* Query UTC information result */
  88 struct ptff_qui {
  89         unsigned int tm : 2;
  90         unsigned int ts : 2;
  91         unsigned int : 28;
  92         unsigned int pad_0x04;
  93         unsigned long leap_event;
  94         short old_leap;
  95         short new_leap;
  96         unsigned int pad_0x14;
  97         unsigned long prt[5];
  98         unsigned long cst[3];
  99         unsigned int skew;
 100         unsigned int pad_0x5c[41];
 101 } __packed;
 102
 103 static inline int ptff(void *ptff_block, size_t len, unsigned int func)
 104 {
 105         typedef struct { char _[len]; } addrtype;
 106         register unsigned int reg0 asm("0") = func;
 107         register unsigned long reg1 asm("1") = (unsigned long) ptff_block;
 108         int rc;
 109
 110         asm volatile(
 111                 "       .word   0x0104\n"
 112                 "       ipm     %0\n"
 113                 "       srl     %0,28\n"
 114                 : "=d" (rc), "+m" (*(addrtype *) ptff_block)
 115                 : "d" (reg0), "d" (reg1) : "cc");
 116         return rc;
 117 }
 118
 119 static inline unsigned long long local_tick_disable(void)
 120 {
 121         unsigned long long old;
 122
 123         old = S390_lowcore.clock_comparator;
 124         S390_lowcore.clock_comparator = -1ULL;
 125         set_clock_comparator(S390_lowcore.clock_comparator);
 126         return old;
 127 }
 128
 129 static inline void local_tick_enable(unsigned long long comp)
 130 {
 131         S390_lowcore.clock_comparator = comp;
 132         set_clock_comparator(S390_lowcore.clock_comparator);
 133 }
 134
 135 #define CLOCK_TICK_RATE         1193180 /* Underlying HZ */
 136 #define STORE_CLOCK_EXT_SIZE    16      /* stcke writes 16 bytes */
 137
 138 typedef unsigned long long cycles_t;
 139
 140 static inline void get_tod_clock_ext(char *clk)
 141 {
 142         typedef struct { char _[STORE_CLOCK_EXT_SIZE]; } addrtype;
 143
 144         asm volatile("stcke %0" : "=Q" (*(addrtype *) clk) : : "cc");
 145 }
 146
 147 static inline unsigned long long get_tod_clock(void)
 148 {
 149         unsigned char clk[STORE_CLOCK_EXT_SIZE];
 150
 151         get_tod_clock_ext(clk);
 152         return *((unsigned long long *)&clk[1]);
 153 }
 154
 155 static inline unsigned long long get_tod_clock_fast(void)
 156 {
 157 #ifdef CONFIG_HAVE_MARCH_Z9_109_FEATURES
 158         unsigned long long clk;
 159
 160         asm volatile("stckf %0" : "=Q" (clk) : : "cc");
 161         return clk;
 162 #else
 163         return get_tod_clock();
 164 #endif
 165 }
 166
 167 static inline cycles_t get_cycles(void)
 168 {
 169         return (cycles_t) get_tod_clock() >> 2;
 170 }
 171
 172 int get_phys_clock(unsigned long long *clock);
 173 void init_cpu_timer(void);
 174 unsigned long long monotonic_clock(void);
 175
 176 void tod_to_timeval(__u64 todval, struct timespec64 *xt);
 177
 178 static inline
 179 void stck_to_timespec64(unsigned long long stck, struct timespec64 *ts)
 180 {
 181         tod_to_timeval(stck - TOD_UNIX_EPOCH, ts);
 182 }
 183
 184 extern u64 sched_clock_base_cc;
 185
 186 /**
 187  * get_clock_monotonic - returns current time in clock rate units
 188  *
 189  * The caller must ensure that preemption is disabled.
 190  * The clock and sched_clock_base get changed via stop_machine.
 191  * Therefore preemption must be disabled when calling this
 192  * function, otherwise the returned value is not guaranteed to
 193  * be monotonic.
 194  */
 195 static inline unsigned long long get_tod_clock_monotonic(void)
 196 {
 197         return get_tod_clock() - sched_clock_base_cc;
 198 }
 199
 200 /**
 201  * tod_to_ns - convert a TOD format value to nanoseconds
 202  * @todval: to be converted TOD format value
 203  * Returns: number of nanoseconds that correspond to the TOD format value
 204  *
 205  * Converting a 64 Bit TOD format value to nanoseconds means that the value
 206  * must be divided by 4.096. In order to achieve that we multiply with 125
 207  * and divide by 512:
 208  *
 209  *    ns = (todval * 125) >> 9;
 210  *
 211  * In order to avoid an overflow with the multiplication we can rewrite this.
 212  * With a split todval == 2^32 * th + tl (th upper 32 bits, tl lower 32 bits)
 213  * we end up with
 214  *
 215  *    ns = ((2^32 * th + tl) * 125 ) >> 9;
 216  * -> ns = (2^23 * th * 125) + ((tl * 125) >> 9);
 217  *
 218  */
 219 static inline unsigned long long tod_to_ns(unsigned long long todval)
 220 {
 221         unsigned long long ns;
 222
 223         ns = ((todval >> 32) << 23) * 125;
 224         ns += ((todval & 0xffffffff) * 125) >> 9;
 225         return ns;
 226 }
 227
 228 #endif