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 <linux/preempt.h> 14 #include <linux/time64.h> 15 #include <asm/lowcore.h> 16 17 /* The value of the TOD clock for 1.1.1970. */ 18 #define TOD_UNIX_EPOCH 0x7d91048bca000000ULL 19 20 extern u64 clock_comparator_max; 21 22 /* Inline functions for clock register access. */ 23 static inline int set_tod_clock(__u64 time) 24 { 25 int cc; 26 27 asm volatile( 28 " sck %1\n" 29 " ipm %0\n" 30 " srl %0,28\n" 31 : "=d" (cc) : "Q" (time) : "cc"); 32 return cc; 33 } 34 35 static inline int store_tod_clock(__u64 *time) 36 { 37 int cc; 38 39 asm volatile( 40 " stck %1\n" 41 " ipm %0\n" 42 " srl %0,28\n" 43 : "=d" (cc), "=Q" (*time) : : "cc"); 44 return cc; 45 } 46 47 static inline void set_clock_comparator(__u64 time) 48 { 49 asm volatile("sckc %0" : : "Q" (time)); 50 } 51 52 void clock_comparator_work(void); 53 54 void __init time_early_init(void); 55 56 extern unsigned char ptff_function_mask[16]; 57 58 /* Function codes for the ptff instruction. */ 59 #define PTFF_QAF 0x00 /* query available functions */ 60 #define PTFF_QTO 0x01 /* query tod offset */ 61 #define PTFF_QSI 0x02 /* query steering information */ 62 #define PTFF_QUI 0x04 /* query UTC information */ 63 #define PTFF_ATO 0x40 /* adjust tod offset */ 64 #define PTFF_STO 0x41 /* set tod offset */ 65 #define PTFF_SFS 0x42 /* set fine steering rate */ 66 #define PTFF_SGS 0x43 /* set gross steering rate */ 67 68 /* Query TOD offset result */ 69 struct ptff_qto { 70 unsigned long long physical_clock; 71 unsigned long long tod_offset; 72 unsigned long long logical_tod_offset; 73 unsigned long long tod_epoch_difference; 74 } __packed; 75 76 static inline int ptff_query(unsigned int nr) 77 { 78 unsigned char *ptr; 79 80 ptr = ptff_function_mask + (nr >> 3); 81 return (*ptr & (0x80 >> (nr & 7))) != 0; 82 } 83 84 /* Query UTC information result */ 85 struct ptff_qui { 86 unsigned int tm : 2; 87 unsigned int ts : 2; 88 unsigned int : 28; 89 unsigned int pad_0x04; 90 unsigned long leap_event; 91 short old_leap; 92 short new_leap; 93 unsigned int pad_0x14; 94 unsigned long prt[5]; 95 unsigned long cst[3]; 96 unsigned int skew; 97 unsigned int pad_0x5c[41]; 98 } __packed; 99 100 /* 101 * ptff - Perform timing facility function 102 * @ptff_block: Pointer to ptff parameter block 103 * @len: Length of parameter block 104 * @func: Function code 105 * Returns: Condition code (0 on success) 106 */ 107 #define ptff(ptff_block, len, func) \ 108 ({ \ 109 struct addrtype { char _[len]; }; \ 110 register unsigned int reg0 asm("0") = func; \ 111 register unsigned long reg1 asm("1") = (unsigned long) (ptff_block);\ 112 int rc; \ 113 \ 114 asm volatile( \ 115 " .word 0x0104\n" \ 116 " ipm %0\n" \ 117 " srl %0,28\n" \ 118 : "=d" (rc), "+m" (*(struct addrtype *) reg1) \ 119 : "d" (reg0), "d" (reg1) : "cc"); \ 120 rc; \ 121 }) 122 123 static inline unsigned long long local_tick_disable(void) 124 { 125 unsigned long long old; 126 127 old = S390_lowcore.clock_comparator; 128 S390_lowcore.clock_comparator = clock_comparator_max; 129 set_clock_comparator(S390_lowcore.clock_comparator); 130 return old; 131 } 132 133 static inline void local_tick_enable(unsigned long long comp) 134 { 135 S390_lowcore.clock_comparator = comp; 136 set_clock_comparator(S390_lowcore.clock_comparator); 137 } 138 139 #define CLOCK_TICK_RATE 1193180 /* Underlying HZ */ 140 #define STORE_CLOCK_EXT_SIZE 16 /* stcke writes 16 bytes */ 141 142 typedef unsigned long long cycles_t; 143 144 static inline void get_tod_clock_ext(char *clk) 145 { 146 typedef struct { char _[STORE_CLOCK_EXT_SIZE]; } addrtype; 147 148 asm volatile("stcke %0" : "=Q" (*(addrtype *) clk) : : "cc"); 149 } 150 151 static inline unsigned long long get_tod_clock(void) 152 { 153 char clk[STORE_CLOCK_EXT_SIZE]; 154 155 get_tod_clock_ext(clk); 156 return *((unsigned long long *)&clk[1]); 157 } 158 159 static inline unsigned long long get_tod_clock_fast(void) 160 { 161 #ifdef CONFIG_HAVE_MARCH_Z9_109_FEATURES 162 unsigned long long clk; 163 164 asm volatile("stckf %0" : "=Q" (clk) : : "cc"); 165 return clk; 166 #else 167 return get_tod_clock(); 168 #endif 169 } 170 171 static inline cycles_t get_cycles(void) 172 { 173 return (cycles_t) get_tod_clock() >> 2; 174 } 175 176 int get_phys_clock(unsigned long *clock); 177 void init_cpu_timer(void); 178 179 extern unsigned char tod_clock_base[16] __aligned(8); 180 181 /** 182 * get_clock_monotonic - returns current time in clock rate units 183 * 184 * The clock and tod_clock_base get changed via stop_machine. 185 * Therefore preemption must be disabled, otherwise the returned 186 * value is not guaranteed to be monotonic. 187 */ 188 static inline unsigned long long get_tod_clock_monotonic(void) 189 { 190 unsigned long long tod; 191 192 preempt_disable_notrace(); 193 tod = get_tod_clock() - *(unsigned long long *) &tod_clock_base[1]; 194 preempt_enable_notrace(); 195 return tod; 196 } 197 198 /** 199 * tod_to_ns - convert a TOD format value to nanoseconds 200 * @todval: to be converted TOD format value 201 * Returns: number of nanoseconds that correspond to the TOD format value 202 * 203 * Converting a 64 Bit TOD format value to nanoseconds means that the value 204 * must be divided by 4.096. In order to achieve that we multiply with 125 205 * and divide by 512: 206 * 207 * ns = (todval * 125) >> 9; 208 * 209 * In order to avoid an overflow with the multiplication we can rewrite this. 210 * With a split todval == 2^9 * th + tl (th upper 55 bits, tl lower 9 bits) 211 * we end up with 212 * 213 * ns = ((2^9 * th + tl) * 125 ) >> 9; 214 * -> ns = (th * 125) + ((tl * 125) >> 9); 215 * 216 */ 217 static inline unsigned long long tod_to_ns(unsigned long long todval) 218 { 219 return ((todval >> 9) * 125) + (((todval & 0x1ff) * 125) >> 9); 220 } 221 222 /** 223 * tod_after - compare two 64 bit TOD values 224 * @a: first 64 bit TOD timestamp 225 * @b: second 64 bit TOD timestamp 226 * 227 * Returns: true if a is later than b 228 */ 229 static inline int tod_after(unsigned long long a, unsigned long long b) 230 { 231 if (MACHINE_HAS_SCC) 232 return (long long) a > (long long) b; 233 return a > b; 234 } 235 236 /** 237 * tod_after_eq - compare two 64 bit TOD values 238 * @a: first 64 bit TOD timestamp 239 * @b: second 64 bit TOD timestamp 240 * 241 * Returns: true if a is later than b 242 */ 243 static inline int tod_after_eq(unsigned long long a, unsigned long long b) 244 { 245 if (MACHINE_HAS_SCC) 246 return (long long) a >= (long long) b; 247 return a >= b; 248 } 249 250 #endif 251