1 /* SPDX-License-Identifier: GPL-2.0 */ 2 /* 3 * S390 version 4 * Copyright IBM Corp. 1999 5 * 6 * Derived from "include/asm-i386/timex.h" 7 * Copyright (C) 1992, Linus Torvalds 8 */ 9 10 #ifndef _ASM_S390_TIMEX_H 11 #define _ASM_S390_TIMEX_H 12 13 #include <asm/lowcore.h> 14 #include <linux/time64.h> 15 16 /* The value of the TOD clock for 1.1.1970. */ 17 #define TOD_UNIX_EPOCH 0x7d91048bca000000ULL 18 19 extern u64 clock_comparator_max; 20 21 /* Inline functions for clock register access. */ 22 static inline int set_tod_clock(__u64 time) 23 { 24 int cc; 25 26 asm volatile( 27 " sck %1\n" 28 " ipm %0\n" 29 " srl %0,28\n" 30 : "=d" (cc) : "Q" (time) : "cc"); 31 return cc; 32 } 33 34 static inline int store_tod_clock(__u64 *time) 35 { 36 int cc; 37 38 asm volatile( 39 " stck %1\n" 40 " ipm %0\n" 41 " srl %0,28\n" 42 : "=d" (cc), "=Q" (*time) : : "cc"); 43 return cc; 44 } 45 46 static inline void set_clock_comparator(__u64 time) 47 { 48 asm volatile("sckc %0" : : "Q" (time)); 49 } 50 51 static inline void store_clock_comparator(__u64 *time) 52 { 53 asm volatile("stckc %0" : "=Q" (*time)); 54 } 55 56 void clock_comparator_work(void); 57 58 void __init time_early_init(void); 59 60 extern unsigned char ptff_function_mask[16]; 61 62 /* Function codes for the ptff instruction. */ 63 #define PTFF_QAF 0x00 /* query available functions */ 64 #define PTFF_QTO 0x01 /* query tod offset */ 65 #define PTFF_QSI 0x02 /* query steering information */ 66 #define PTFF_QUI 0x04 /* query UTC information */ 67 #define PTFF_ATO 0x40 /* adjust tod offset */ 68 #define PTFF_STO 0x41 /* set tod offset */ 69 #define PTFF_SFS 0x42 /* set fine steering rate */ 70 #define PTFF_SGS 0x43 /* set gross steering rate */ 71 72 /* Query TOD offset result */ 73 struct ptff_qto { 74 unsigned long long physical_clock; 75 unsigned long long tod_offset; 76 unsigned long long logical_tod_offset; 77 unsigned long long tod_epoch_difference; 78 } __packed; 79 80 static inline int ptff_query(unsigned int nr) 81 { 82 unsigned char *ptr; 83 84 ptr = ptff_function_mask + (nr >> 3); 85 return (*ptr & (0x80 >> (nr & 7))) != 0; 86 } 87 88 /* Query UTC information result */ 89 struct ptff_qui { 90 unsigned int tm : 2; 91 unsigned int ts : 2; 92 unsigned int : 28; 93 unsigned int pad_0x04; 94 unsigned long leap_event; 95 short old_leap; 96 short new_leap; 97 unsigned int pad_0x14; 98 unsigned long prt[5]; 99 unsigned long cst[3]; 100 unsigned int skew; 101 unsigned int pad_0x5c[41]; 102 } __packed; 103 104 /* 105 * ptff - Perform timing facility function 106 * @ptff_block: Pointer to ptff parameter block 107 * @len: Length of parameter block 108 * @func: Function code 109 * Returns: Condition code (0 on success) 110 */ 111 #define ptff(ptff_block, len, func) \ 112 ({ \ 113 struct addrtype { char _[len]; }; \ 114 register unsigned int reg0 asm("0") = func; \ 115 register unsigned long reg1 asm("1") = (unsigned long) (ptff_block);\ 116 int rc; \ 117 \ 118 asm volatile( \ 119 " .word 0x0104\n" \ 120 " ipm %0\n" \ 121 " srl %0,28\n" \ 122 : "=d" (rc), "+m" (*(struct addrtype *) reg1) \ 123 : "d" (reg0), "d" (reg1) : "cc"); \ 124 rc; \ 125 }) 126 127 static inline unsigned long long local_tick_disable(void) 128 { 129 unsigned long long old; 130 131 old = S390_lowcore.clock_comparator; 132 S390_lowcore.clock_comparator = clock_comparator_max; 133 set_clock_comparator(S390_lowcore.clock_comparator); 134 return old; 135 } 136 137 static inline void local_tick_enable(unsigned long long comp) 138 { 139 S390_lowcore.clock_comparator = comp; 140 set_clock_comparator(S390_lowcore.clock_comparator); 141 } 142 143 #define CLOCK_TICK_RATE 1193180 /* Underlying HZ */ 144 #define STORE_CLOCK_EXT_SIZE 16 /* stcke writes 16 bytes */ 145 146 typedef unsigned long long cycles_t; 147 148 static inline void get_tod_clock_ext(char *clk) 149 { 150 typedef struct { char _[STORE_CLOCK_EXT_SIZE]; } addrtype; 151 152 asm volatile("stcke %0" : "=Q" (*(addrtype *) clk) : : "cc"); 153 } 154 155 static inline unsigned long long get_tod_clock(void) 156 { 157 unsigned char clk[STORE_CLOCK_EXT_SIZE]; 158 159 get_tod_clock_ext(clk); 160 return *((unsigned long long *)&clk[1]); 161 } 162 163 static inline unsigned long long get_tod_clock_fast(void) 164 { 165 #ifdef CONFIG_HAVE_MARCH_Z9_109_FEATURES 166 unsigned long long clk; 167 168 asm volatile("stckf %0" : "=Q" (clk) : : "cc"); 169 return clk; 170 #else 171 return get_tod_clock(); 172 #endif 173 } 174 175 static inline cycles_t get_cycles(void) 176 { 177 return (cycles_t) get_tod_clock() >> 2; 178 } 179 180 int get_phys_clock(unsigned long *clock); 181 void init_cpu_timer(void); 182 unsigned long long monotonic_clock(void); 183 184 extern unsigned char tod_clock_base[16] __aligned(8); 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 tod_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() - *(unsigned long long *) &tod_clock_base[1]; 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 == 2^9 * th + tl (th upper 55 bits, tl lower 9 bits) 213 * we end up with 214 * 215 * ns = ((2^9 * th + tl) * 125 ) >> 9; 216 * -> ns = (th * 125) + ((tl * 125) >> 9); 217 * 218 */ 219 static inline unsigned long long tod_to_ns(unsigned long long todval) 220 { 221 return ((todval >> 9) * 125) + (((todval & 0x1ff) * 125) >> 9); 222 } 223 224 /** 225 * tod_after - compare two 64 bit TOD values 226 * @a: first 64 bit TOD timestamp 227 * @b: second 64 bit TOD timestamp 228 * 229 * Returns: true if a is later than b 230 */ 231 static inline int tod_after(unsigned long long a, unsigned long long b) 232 { 233 if (MACHINE_HAS_SCC) 234 return (long long) a > (long long) b; 235 return a > b; 236 } 237 238 /** 239 * tod_after_eq - compare two 64 bit TOD values 240 * @a: first 64 bit TOD timestamp 241 * @b: second 64 bit TOD timestamp 242 * 243 * Returns: true if a is later than b 244 */ 245 static inline int tod_after_eq(unsigned long long a, unsigned long long b) 246 { 247 if (MACHINE_HAS_SCC) 248 return (long long) a >= (long long) b; 249 return a >= b; 250 } 251 252 #endif 253