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 set_tod_programmable_field(u16 val) 53 { 54 register unsigned long reg0 asm("0") = val; 55 56 asm volatile("sckpf" : : "d" (reg0)); 57 } 58 59 void clock_comparator_work(void); 60 61 void __init time_early_init(void); 62 63 extern unsigned char ptff_function_mask[16]; 64 65 /* Function codes for the ptff instruction. */ 66 #define PTFF_QAF 0x00 /* query available functions */ 67 #define PTFF_QTO 0x01 /* query tod offset */ 68 #define PTFF_QSI 0x02 /* query steering information */ 69 #define PTFF_QUI 0x04 /* query UTC information */ 70 #define PTFF_ATO 0x40 /* adjust tod offset */ 71 #define PTFF_STO 0x41 /* set tod offset */ 72 #define PTFF_SFS 0x42 /* set fine steering rate */ 73 #define PTFF_SGS 0x43 /* set gross steering rate */ 74 75 /* Query TOD offset result */ 76 struct ptff_qto { 77 unsigned long long physical_clock; 78 unsigned long long tod_offset; 79 unsigned long long logical_tod_offset; 80 unsigned long long tod_epoch_difference; 81 } __packed; 82 83 static inline int ptff_query(unsigned int nr) 84 { 85 unsigned char *ptr; 86 87 ptr = ptff_function_mask + (nr >> 3); 88 return (*ptr & (0x80 >> (nr & 7))) != 0; 89 } 90 91 /* Query UTC information result */ 92 struct ptff_qui { 93 unsigned int tm : 2; 94 unsigned int ts : 2; 95 unsigned int : 28; 96 unsigned int pad_0x04; 97 unsigned long leap_event; 98 short old_leap; 99 short new_leap; 100 unsigned int pad_0x14; 101 unsigned long prt[5]; 102 unsigned long cst[3]; 103 unsigned int skew; 104 unsigned int pad_0x5c[41]; 105 } __packed; 106 107 /* 108 * ptff - Perform timing facility function 109 * @ptff_block: Pointer to ptff parameter block 110 * @len: Length of parameter block 111 * @func: Function code 112 * Returns: Condition code (0 on success) 113 */ 114 #define ptff(ptff_block, len, func) \ 115 ({ \ 116 struct addrtype { char _[len]; }; \ 117 register unsigned int reg0 asm("0") = func; \ 118 register unsigned long reg1 asm("1") = (unsigned long) (ptff_block);\ 119 int rc; \ 120 \ 121 asm volatile( \ 122 " .word 0x0104\n" \ 123 " ipm %0\n" \ 124 " srl %0,28\n" \ 125 : "=d" (rc), "+m" (*(struct addrtype *) reg1) \ 126 : "d" (reg0), "d" (reg1) : "cc"); \ 127 rc; \ 128 }) 129 130 static inline unsigned long long local_tick_disable(void) 131 { 132 unsigned long long old; 133 134 old = S390_lowcore.clock_comparator; 135 S390_lowcore.clock_comparator = clock_comparator_max; 136 set_clock_comparator(S390_lowcore.clock_comparator); 137 return old; 138 } 139 140 static inline void local_tick_enable(unsigned long long comp) 141 { 142 S390_lowcore.clock_comparator = comp; 143 set_clock_comparator(S390_lowcore.clock_comparator); 144 } 145 146 #define CLOCK_TICK_RATE 1193180 /* Underlying HZ */ 147 #define STORE_CLOCK_EXT_SIZE 16 /* stcke writes 16 bytes */ 148 149 typedef unsigned long long cycles_t; 150 151 static inline void get_tod_clock_ext(char *clk) 152 { 153 typedef struct { char _[STORE_CLOCK_EXT_SIZE]; } addrtype; 154 155 asm volatile("stcke %0" : "=Q" (*(addrtype *) clk) : : "cc"); 156 } 157 158 static inline unsigned long long get_tod_clock(void) 159 { 160 char clk[STORE_CLOCK_EXT_SIZE]; 161 162 get_tod_clock_ext(clk); 163 return *((unsigned long long *)&clk[1]); 164 } 165 166 static inline unsigned long long get_tod_clock_fast(void) 167 { 168 #ifdef CONFIG_HAVE_MARCH_Z9_109_FEATURES 169 unsigned long long clk; 170 171 asm volatile("stckf %0" : "=Q" (clk) : : "cc"); 172 return clk; 173 #else 174 return get_tod_clock(); 175 #endif 176 } 177 178 static inline cycles_t get_cycles(void) 179 { 180 return (cycles_t) get_tod_clock() >> 2; 181 } 182 183 int get_phys_clock(unsigned long *clock); 184 void init_cpu_timer(void); 185 186 extern unsigned char tod_clock_base[16] __aligned(8); 187 188 /** 189 * get_clock_monotonic - returns current time in clock rate units 190 * 191 * The clock and tod_clock_base get changed via stop_machine. 192 * Therefore preemption must be disabled, otherwise the returned 193 * value is not guaranteed to be monotonic. 194 */ 195 static inline unsigned long long get_tod_clock_monotonic(void) 196 { 197 unsigned long long tod; 198 199 preempt_disable_notrace(); 200 tod = get_tod_clock() - *(unsigned long long *) &tod_clock_base[1]; 201 preempt_enable_notrace(); 202 return tod; 203 } 204 205 /** 206 * tod_to_ns - convert a TOD format value to nanoseconds 207 * @todval: to be converted TOD format value 208 * Returns: number of nanoseconds that correspond to the TOD format value 209 * 210 * Converting a 64 Bit TOD format value to nanoseconds means that the value 211 * must be divided by 4.096. In order to achieve that we multiply with 125 212 * and divide by 512: 213 * 214 * ns = (todval * 125) >> 9; 215 * 216 * In order to avoid an overflow with the multiplication we can rewrite this. 217 * With a split todval == 2^9 * th + tl (th upper 55 bits, tl lower 9 bits) 218 * we end up with 219 * 220 * ns = ((2^9 * th + tl) * 125 ) >> 9; 221 * -> ns = (th * 125) + ((tl * 125) >> 9); 222 * 223 */ 224 static inline unsigned long long tod_to_ns(unsigned long long todval) 225 { 226 return ((todval >> 9) * 125) + (((todval & 0x1ff) * 125) >> 9); 227 } 228 229 /** 230 * tod_after - compare two 64 bit TOD values 231 * @a: first 64 bit TOD timestamp 232 * @b: second 64 bit TOD timestamp 233 * 234 * Returns: true if a is later than b 235 */ 236 static inline int tod_after(unsigned long long a, unsigned long long b) 237 { 238 if (MACHINE_HAS_SCC) 239 return (long long) a > (long long) b; 240 return a > b; 241 } 242 243 /** 244 * tod_after_eq - compare two 64 bit TOD values 245 * @a: first 64 bit TOD timestamp 246 * @b: second 64 bit TOD timestamp 247 * 248 * Returns: true if a is later than b 249 */ 250 static inline int tod_after_eq(unsigned long long a, unsigned long long b) 251 { 252 if (MACHINE_HAS_SCC) 253 return (long long) a >= (long long) b; 254 return a >= b; 255 } 256 257 #endif 258