1 /* SPDX-License-Identifier: GPL-2.0-or-later */ 2 /* 3 * PTP 1588 clock support 4 * 5 * Copyright (C) 2010 OMICRON electronics GmbH 6 */ 7 8 #ifndef _PTP_CLOCK_KERNEL_H_ 9 #define _PTP_CLOCK_KERNEL_H_ 10 11 #include <linux/device.h> 12 #include <linux/pps_kernel.h> 13 #include <linux/ptp_clock.h> 14 #include <linux/timecounter.h> 15 #include <linux/skbuff.h> 16 17 #define PTP_CLOCK_NAME_LEN 32 18 /** 19 * struct ptp_clock_request - request PTP clock event 20 * 21 * @type: The type of the request. 22 * EXTTS: Configure external trigger timestamping 23 * PEROUT: Configure periodic output signal (e.g. PPS) 24 * PPS: trigger internal PPS event for input 25 * into kernel PPS subsystem 26 * @extts: describes configuration for external trigger timestamping. 27 * This is only valid when event == PTP_CLK_REQ_EXTTS. 28 * @perout: describes configuration for periodic output. 29 * This is only valid when event == PTP_CLK_REQ_PEROUT. 30 */ 31 32 struct ptp_clock_request { 33 enum { 34 PTP_CLK_REQ_EXTTS, 35 PTP_CLK_REQ_PEROUT, 36 PTP_CLK_REQ_PPS, 37 } type; 38 union { 39 struct ptp_extts_request extts; 40 struct ptp_perout_request perout; 41 }; 42 }; 43 44 struct system_device_crosststamp; 45 46 /** 47 * struct ptp_system_timestamp - system time corresponding to a PHC timestamp 48 */ 49 struct ptp_system_timestamp { 50 struct timespec64 pre_ts; 51 struct timespec64 post_ts; 52 }; 53 54 /** 55 * struct ptp_clock_info - describes a PTP hardware clock 56 * 57 * @owner: The clock driver should set to THIS_MODULE. 58 * @name: A short "friendly name" to identify the clock and to 59 * help distinguish PHY based devices from MAC based ones. 60 * The string is not meant to be a unique id. 61 * @max_adj: The maximum possible frequency adjustment, in parts per billon. 62 * @n_alarm: The number of programmable alarms. 63 * @n_ext_ts: The number of external time stamp channels. 64 * @n_per_out: The number of programmable periodic signals. 65 * @n_pins: The number of programmable pins. 66 * @pps: Indicates whether the clock supports a PPS callback. 67 * @pin_config: Array of length 'n_pins'. If the number of 68 * programmable pins is nonzero, then drivers must 69 * allocate and initialize this array. 70 * 71 * clock operations 72 * 73 * @adjfine: Adjusts the frequency of the hardware clock. 74 * parameter scaled_ppm: Desired frequency offset from 75 * nominal frequency in parts per million, but with a 76 * 16 bit binary fractional field. 77 * 78 * @adjfreq: Adjusts the frequency of the hardware clock. 79 * This method is deprecated. New drivers should implement 80 * the @adjfine method instead. 81 * parameter delta: Desired frequency offset from nominal frequency 82 * in parts per billion 83 * 84 * @adjphase: Adjusts the phase offset of the hardware clock. 85 * parameter delta: Desired change in nanoseconds. 86 * 87 * @adjtime: Shifts the time of the hardware clock. 88 * parameter delta: Desired change in nanoseconds. 89 * 90 * @gettime64: Reads the current time from the hardware clock. 91 * This method is deprecated. New drivers should implement 92 * the @gettimex64 method instead. 93 * parameter ts: Holds the result. 94 * 95 * @gettimex64: Reads the current time from the hardware clock and optionally 96 * also the system clock. 97 * parameter ts: Holds the PHC timestamp. 98 * parameter sts: If not NULL, it holds a pair of timestamps from 99 * the system clock. The first reading is made right before 100 * reading the lowest bits of the PHC timestamp and the second 101 * reading immediately follows that. 102 * 103 * @getcrosststamp: Reads the current time from the hardware clock and 104 * system clock simultaneously. 105 * parameter cts: Contains timestamp (device,system) pair, 106 * where system time is realtime and monotonic. 107 * 108 * @settime64: Set the current time on the hardware clock. 109 * parameter ts: Time value to set. 110 * 111 * @getcycles64: Reads the current free running cycle counter from the hardware 112 * clock. 113 * If @getcycles64 and @getcyclesx64 are not supported, then 114 * @gettime64 or @gettimex64 will be used as default 115 * implementation. 116 * parameter ts: Holds the result. 117 * 118 * @getcyclesx64: Reads the current free running cycle counter from the 119 * hardware clock and optionally also the system clock. 120 * If @getcycles64 and @getcyclesx64 are not supported, then 121 * @gettimex64 will be used as default implementation if 122 * available. 123 * parameter ts: Holds the PHC timestamp. 124 * parameter sts: If not NULL, it holds a pair of timestamps 125 * from the system clock. The first reading is made right before 126 * reading the lowest bits of the PHC timestamp and the second 127 * reading immediately follows that. 128 * 129 * @getcrosscycles: Reads the current free running cycle counter from the 130 * hardware clock and system clock simultaneously. 131 * If @getcycles64 and @getcyclesx64 are not supported, then 132 * @getcrosststamp will be used as default implementation if 133 * available. 134 * parameter cts: Contains timestamp (device,system) pair, 135 * where system time is realtime and monotonic. 136 * 137 * @enable: Request driver to enable or disable an ancillary feature. 138 * parameter request: Desired resource to enable or disable. 139 * parameter on: Caller passes one to enable or zero to disable. 140 * 141 * @verify: Confirm that a pin can perform a given function. The PTP 142 * Hardware Clock subsystem maintains the 'pin_config' 143 * array on behalf of the drivers, but the PHC subsystem 144 * assumes that every pin can perform every function. This 145 * hook gives drivers a way of telling the core about 146 * limitations on specific pins. This function must return 147 * zero if the function can be assigned to this pin, and 148 * nonzero otherwise. 149 * parameter pin: index of the pin in question. 150 * parameter func: the desired function to use. 151 * parameter chan: the function channel index to use. 152 * 153 * @do_aux_work: Request driver to perform auxiliary (periodic) operations 154 * Driver should return delay of the next auxiliary work 155 * scheduling time (>=0) or negative value in case further 156 * scheduling is not required. 157 * 158 * Drivers should embed their ptp_clock_info within a private 159 * structure, obtaining a reference to it using container_of(). 160 * 161 * The callbacks must all return zero on success, non-zero otherwise. 162 */ 163 164 struct ptp_clock_info { 165 struct module *owner; 166 char name[PTP_CLOCK_NAME_LEN]; 167 s32 max_adj; 168 int n_alarm; 169 int n_ext_ts; 170 int n_per_out; 171 int n_pins; 172 int pps; 173 struct ptp_pin_desc *pin_config; 174 int (*adjfine)(struct ptp_clock_info *ptp, long scaled_ppm); 175 int (*adjfreq)(struct ptp_clock_info *ptp, s32 delta); 176 int (*adjphase)(struct ptp_clock_info *ptp, s32 phase); 177 int (*adjtime)(struct ptp_clock_info *ptp, s64 delta); 178 int (*gettime64)(struct ptp_clock_info *ptp, struct timespec64 *ts); 179 int (*gettimex64)(struct ptp_clock_info *ptp, struct timespec64 *ts, 180 struct ptp_system_timestamp *sts); 181 int (*getcrosststamp)(struct ptp_clock_info *ptp, 182 struct system_device_crosststamp *cts); 183 int (*settime64)(struct ptp_clock_info *p, const struct timespec64 *ts); 184 int (*getcycles64)(struct ptp_clock_info *ptp, struct timespec64 *ts); 185 int (*getcyclesx64)(struct ptp_clock_info *ptp, struct timespec64 *ts, 186 struct ptp_system_timestamp *sts); 187 int (*getcrosscycles)(struct ptp_clock_info *ptp, 188 struct system_device_crosststamp *cts); 189 int (*enable)(struct ptp_clock_info *ptp, 190 struct ptp_clock_request *request, int on); 191 int (*verify)(struct ptp_clock_info *ptp, unsigned int pin, 192 enum ptp_pin_function func, unsigned int chan); 193 long (*do_aux_work)(struct ptp_clock_info *ptp); 194 }; 195 196 struct ptp_clock; 197 198 enum ptp_clock_events { 199 PTP_CLOCK_ALARM, 200 PTP_CLOCK_EXTTS, 201 PTP_CLOCK_PPS, 202 PTP_CLOCK_PPSUSR, 203 }; 204 205 /** 206 * struct ptp_clock_event - decribes a PTP hardware clock event 207 * 208 * @type: One of the ptp_clock_events enumeration values. 209 * @index: Identifies the source of the event. 210 * @timestamp: When the event occurred (%PTP_CLOCK_EXTTS only). 211 * @pps_times: When the event occurred (%PTP_CLOCK_PPSUSR only). 212 */ 213 214 struct ptp_clock_event { 215 int type; 216 int index; 217 union { 218 u64 timestamp; 219 struct pps_event_time pps_times; 220 }; 221 }; 222 223 /** 224 * scaled_ppm_to_ppb() - convert scaled ppm to ppb 225 * 226 * @ppm: Parts per million, but with a 16 bit binary fractional field 227 */ 228 static inline long scaled_ppm_to_ppb(long ppm) 229 { 230 /* 231 * The 'freq' field in the 'struct timex' is in parts per 232 * million, but with a 16 bit binary fractional field. 233 * 234 * We want to calculate 235 * 236 * ppb = scaled_ppm * 1000 / 2^16 237 * 238 * which simplifies to 239 * 240 * ppb = scaled_ppm * 125 / 2^13 241 */ 242 s64 ppb = 1 + ppm; 243 244 ppb *= 125; 245 ppb >>= 13; 246 return (long)ppb; 247 } 248 249 #if IS_ENABLED(CONFIG_PTP_1588_CLOCK) 250 251 /** 252 * ptp_clock_register() - register a PTP hardware clock driver 253 * 254 * @info: Structure describing the new clock. 255 * @parent: Pointer to the parent device of the new clock. 256 * 257 * Returns a valid pointer on success or PTR_ERR on failure. If PHC 258 * support is missing at the configuration level, this function 259 * returns NULL, and drivers are expected to gracefully handle that 260 * case separately. 261 */ 262 263 extern struct ptp_clock *ptp_clock_register(struct ptp_clock_info *info, 264 struct device *parent); 265 266 /** 267 * ptp_clock_unregister() - unregister a PTP hardware clock driver 268 * 269 * @ptp: The clock to remove from service. 270 */ 271 272 extern int ptp_clock_unregister(struct ptp_clock *ptp); 273 274 /** 275 * ptp_clock_event() - notify the PTP layer about an event 276 * 277 * @ptp: The clock obtained from ptp_clock_register(). 278 * @event: Message structure describing the event. 279 */ 280 281 extern void ptp_clock_event(struct ptp_clock *ptp, 282 struct ptp_clock_event *event); 283 284 /** 285 * ptp_clock_index() - obtain the device index of a PTP clock 286 * 287 * @ptp: The clock obtained from ptp_clock_register(). 288 */ 289 290 extern int ptp_clock_index(struct ptp_clock *ptp); 291 292 /** 293 * ptp_find_pin() - obtain the pin index of a given auxiliary function 294 * 295 * The caller must hold ptp_clock::pincfg_mux. Drivers do not have 296 * access to that mutex as ptp_clock is an opaque type. However, the 297 * core code acquires the mutex before invoking the driver's 298 * ptp_clock_info::enable() callback, and so drivers may call this 299 * function from that context. 300 * 301 * @ptp: The clock obtained from ptp_clock_register(). 302 * @func: One of the ptp_pin_function enumerated values. 303 * @chan: The particular functional channel to find. 304 * Return: Pin index in the range of zero to ptp_clock_caps.n_pins - 1, 305 * or -1 if the auxiliary function cannot be found. 306 */ 307 308 int ptp_find_pin(struct ptp_clock *ptp, 309 enum ptp_pin_function func, unsigned int chan); 310 311 /** 312 * ptp_find_pin_unlocked() - wrapper for ptp_find_pin() 313 * 314 * This function acquires the ptp_clock::pincfg_mux mutex before 315 * invoking ptp_find_pin(). Instead of using this function, drivers 316 * should most likely call ptp_find_pin() directly from their 317 * ptp_clock_info::enable() method. 318 * 319 */ 320 321 int ptp_find_pin_unlocked(struct ptp_clock *ptp, 322 enum ptp_pin_function func, unsigned int chan); 323 324 /** 325 * ptp_schedule_worker() - schedule ptp auxiliary work 326 * 327 * @ptp: The clock obtained from ptp_clock_register(). 328 * @delay: number of jiffies to wait before queuing 329 * See kthread_queue_delayed_work() for more info. 330 */ 331 332 int ptp_schedule_worker(struct ptp_clock *ptp, unsigned long delay); 333 334 /** 335 * ptp_cancel_worker_sync() - cancel ptp auxiliary clock 336 * 337 * @ptp: The clock obtained from ptp_clock_register(). 338 */ 339 void ptp_cancel_worker_sync(struct ptp_clock *ptp); 340 341 #else 342 static inline struct ptp_clock *ptp_clock_register(struct ptp_clock_info *info, 343 struct device *parent) 344 { return NULL; } 345 static inline int ptp_clock_unregister(struct ptp_clock *ptp) 346 { return 0; } 347 static inline void ptp_clock_event(struct ptp_clock *ptp, 348 struct ptp_clock_event *event) 349 { } 350 static inline int ptp_clock_index(struct ptp_clock *ptp) 351 { return -1; } 352 static inline int ptp_find_pin(struct ptp_clock *ptp, 353 enum ptp_pin_function func, unsigned int chan) 354 { return -1; } 355 static inline int ptp_find_pin_unlocked(struct ptp_clock *ptp, 356 enum ptp_pin_function func, 357 unsigned int chan) 358 { return -1; } 359 static inline int ptp_schedule_worker(struct ptp_clock *ptp, 360 unsigned long delay) 361 { return -EOPNOTSUPP; } 362 static inline void ptp_cancel_worker_sync(struct ptp_clock *ptp) 363 { } 364 #endif 365 366 #if IS_BUILTIN(CONFIG_PTP_1588_CLOCK) 367 /* 368 * These are called by the network core, and don't work if PTP is in 369 * a loadable module. 370 */ 371 372 /** 373 * ptp_get_vclocks_index() - get all vclocks index on pclock, and 374 * caller is responsible to free memory 375 * of vclock_index 376 * 377 * @pclock_index: phc index of ptp pclock. 378 * @vclock_index: pointer to pointer of vclock index. 379 * 380 * return number of vclocks. 381 */ 382 int ptp_get_vclocks_index(int pclock_index, int **vclock_index); 383 384 /** 385 * ptp_convert_timestamp() - convert timestamp to a ptp vclock time 386 * 387 * @hwtstamp: timestamp 388 * @vclock_index: phc index of ptp vclock. 389 * 390 * Returns converted timestamp, or 0 on error. 391 */ 392 ktime_t ptp_convert_timestamp(const ktime_t *hwtstamp, int vclock_index); 393 #else 394 static inline int ptp_get_vclocks_index(int pclock_index, int **vclock_index) 395 { return 0; } 396 static inline ktime_t ptp_convert_timestamp(const ktime_t *hwtstamp, 397 int vclock_index) 398 { return 0; } 399 400 #endif 401 402 static inline void ptp_read_system_prets(struct ptp_system_timestamp *sts) 403 { 404 if (sts) 405 ktime_get_real_ts64(&sts->pre_ts); 406 } 407 408 static inline void ptp_read_system_postts(struct ptp_system_timestamp *sts) 409 { 410 if (sts) 411 ktime_get_real_ts64(&sts->post_ts); 412 } 413 414 #endif 415