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 static inline void store_clock_comparator(__u64 *time) 53 { 54 asm volatile("stckc %0" : "=Q" (*time)); 55 } 56 57 void clock_comparator_work(void); 58 59 void __init time_early_init(void); 60 61 extern unsigned char ptff_function_mask[16]; 62 63 /* Function codes for the ptff instruction. */ 64 #define PTFF_QAF 0x00 /* query available functions */ 65 #define PTFF_QTO 0x01 /* query tod offset */ 66 #define PTFF_QSI 0x02 /* query steering information */ 67 #define PTFF_QUI 0x04 /* query UTC information */ 68 #define PTFF_ATO 0x40 /* adjust tod offset */ 69 #define PTFF_STO 0x41 /* set tod offset */ 70 #define PTFF_SFS 0x42 /* set fine steering rate */ 71 #define PTFF_SGS 0x43 /* set gross steering rate */ 72 73 /* Query TOD offset result */ 74 struct ptff_qto { 75 unsigned long long physical_clock; 76 unsigned long long tod_offset; 77 unsigned long long logical_tod_offset; 78 unsigned long long tod_epoch_difference; 79 } __packed; 80 81 static inline int ptff_query(unsigned int nr) 82 { 83 unsigned char *ptr; 84 85 ptr = ptff_function_mask + (nr >> 3); 86 return (*ptr & (0x80 >> (nr & 7))) != 0; 87 } 88 89 /* Query UTC information result */ 90 struct ptff_qui { 91 unsigned int tm : 2; 92 unsigned int ts : 2; 93 unsigned int : 28; 94 unsigned int pad_0x04; 95 unsigned long leap_event; 96 short old_leap; 97 short new_leap; 98 unsigned int pad_0x14; 99 unsigned long prt[5]; 100 unsigned long cst[3]; 101 unsigned int skew; 102 unsigned int pad_0x5c[41]; 103 } __packed; 104 105 /* 106 * ptff - Perform timing facility function 107 * @ptff_block: Pointer to ptff parameter block 108 * @len: Length of parameter block 109 * @func: Function code 110 * Returns: Condition code (0 on success) 111 */ 112 #define ptff(ptff_block, len, func) \ 113 ({ \ 114 struct addrtype { char _[len]; }; \ 115 register unsigned int reg0 asm("0") = func; \ 116 register unsigned long reg1 asm("1") = (unsigned long) (ptff_block);\ 117 int rc; \ 118 \ 119 asm volatile( \ 120 " .word 0x0104\n" \ 121 " ipm %0\n" \ 122 " srl %0,28\n" \ 123 : "=d" (rc), "+m" (*(struct addrtype *) reg1) \ 124 : "d" (reg0), "d" (reg1) : "cc"); \ 125 rc; \ 126 }) 127 128 static inline unsigned long long local_tick_disable(void) 129 { 130 unsigned long long old; 131 132 old = S390_lowcore.clock_comparator; 133 S390_lowcore.clock_comparator = clock_comparator_max; 134 set_clock_comparator(S390_lowcore.clock_comparator); 135 return old; 136 } 137 138 static inline void local_tick_enable(unsigned long long comp) 139 { 140 S390_lowcore.clock_comparator = comp; 141 set_clock_comparator(S390_lowcore.clock_comparator); 142 } 143 144 #define CLOCK_TICK_RATE 1193180 /* Underlying HZ */ 145 #define STORE_CLOCK_EXT_SIZE 16 /* stcke writes 16 bytes */ 146 147 typedef unsigned long long cycles_t; 148 149 static inline void get_tod_clock_ext(char *clk) 150 { 151 typedef struct { char _[STORE_CLOCK_EXT_SIZE]; } addrtype; 152 153 asm volatile("stcke %0" : "=Q" (*(addrtype *) clk) : : "cc"); 154 } 155 156 static inline unsigned long long get_tod_clock(void) 157 { 158 char clk[STORE_CLOCK_EXT_SIZE]; 159 160 get_tod_clock_ext(clk); 161 return *((unsigned long long *)&clk[1]); 162 } 163 164 static inline unsigned long long get_tod_clock_fast(void) 165 { 166 #ifdef CONFIG_HAVE_MARCH_Z9_109_FEATURES 167 unsigned long long clk; 168 169 asm volatile("stckf %0" : "=Q" (clk) : : "cc"); 170 return clk; 171 #else 172 return get_tod_clock(); 173 #endif 174 } 175 176 static inline cycles_t get_cycles(void) 177 { 178 return (cycles_t) get_tod_clock() >> 2; 179 } 180 181 int get_phys_clock(unsigned long *clock); 182 void init_cpu_timer(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 clock and tod_clock_base get changed via stop_machine. 190 * Therefore preemption must be disabled, otherwise the returned 191 * value is not guaranteed to be monotonic. 192 */ 193 static inline unsigned long long get_tod_clock_monotonic(void) 194 { 195 unsigned long long tod; 196 197 preempt_disable_notrace(); 198 tod = get_tod_clock() - *(unsigned long long *) &tod_clock_base[1]; 199 preempt_enable_notrace(); 200 return tod; 201 } 202 203 /** 204 * tod_to_ns - convert a TOD format value to nanoseconds 205 * @todval: to be converted TOD format value 206 * Returns: number of nanoseconds that correspond to the TOD format value 207 * 208 * Converting a 64 Bit TOD format value to nanoseconds means that the value 209 * must be divided by 4.096. In order to achieve that we multiply with 125 210 * and divide by 512: 211 * 212 * ns = (todval * 125) >> 9; 213 * 214 * In order to avoid an overflow with the multiplication we can rewrite this. 215 * With a split todval == 2^9 * th + tl (th upper 55 bits, tl lower 9 bits) 216 * we end up with 217 * 218 * ns = ((2^9 * th + tl) * 125 ) >> 9; 219 * -> ns = (th * 125) + ((tl * 125) >> 9); 220 * 221 */ 222 static inline unsigned long long tod_to_ns(unsigned long long todval) 223 { 224 return ((todval >> 9) * 125) + (((todval & 0x1ff) * 125) >> 9); 225 } 226 227 /** 228 * tod_after - compare two 64 bit TOD values 229 * @a: first 64 bit TOD timestamp 230 * @b: second 64 bit TOD timestamp 231 * 232 * Returns: true if a is later than b 233 */ 234 static inline int tod_after(unsigned long long a, unsigned long long b) 235 { 236 if (MACHINE_HAS_SCC) 237 return (long long) a > (long long) b; 238 return a > b; 239 } 240 241 /** 242 * tod_after_eq - compare two 64 bit TOD values 243 * @a: first 64 bit TOD timestamp 244 * @b: second 64 bit TOD timestamp 245 * 246 * Returns: true if a is later than b 247 */ 248 static inline int tod_after_eq(unsigned long long a, unsigned long long b) 249 { 250 if (MACHINE_HAS_SCC) 251 return (long long) a >= (long long) b; 252 return a >= b; 253 } 254 255 #endif 256