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 * @enable: Request driver to enable or disable an ancillary feature. 112 * parameter request: Desired resource to enable or disable. 113 * parameter on: Caller passes one to enable or zero to disable. 114 * 115 * @verify: Confirm that a pin can perform a given function. The PTP 116 * Hardware Clock subsystem maintains the 'pin_config' 117 * array on behalf of the drivers, but the PHC subsystem 118 * assumes that every pin can perform every function. This 119 * hook gives drivers a way of telling the core about 120 * limitations on specific pins. This function must return 121 * zero if the function can be assigned to this pin, and 122 * nonzero otherwise. 123 * parameter pin: index of the pin in question. 124 * parameter func: the desired function to use. 125 * parameter chan: the function channel index to use. 126 * 127 * @do_aux_work: Request driver to perform auxiliary (periodic) operations 128 * Driver should return delay of the next auxiliary work 129 * scheduling time (>=0) or negative value in case further 130 * scheduling is not required. 131 * 132 * Drivers should embed their ptp_clock_info within a private 133 * structure, obtaining a reference to it using container_of(). 134 * 135 * The callbacks must all return zero on success, non-zero otherwise. 136 */ 137 138 struct ptp_clock_info { 139 struct module *owner; 140 char name[PTP_CLOCK_NAME_LEN]; 141 s32 max_adj; 142 int n_alarm; 143 int n_ext_ts; 144 int n_per_out; 145 int n_pins; 146 int pps; 147 struct ptp_pin_desc *pin_config; 148 int (*adjfine)(struct ptp_clock_info *ptp, long scaled_ppm); 149 int (*adjfreq)(struct ptp_clock_info *ptp, s32 delta); 150 int (*adjphase)(struct ptp_clock_info *ptp, s32 phase); 151 int (*adjtime)(struct ptp_clock_info *ptp, s64 delta); 152 int (*gettime64)(struct ptp_clock_info *ptp, struct timespec64 *ts); 153 int (*gettimex64)(struct ptp_clock_info *ptp, struct timespec64 *ts, 154 struct ptp_system_timestamp *sts); 155 int (*getcrosststamp)(struct ptp_clock_info *ptp, 156 struct system_device_crosststamp *cts); 157 int (*settime64)(struct ptp_clock_info *p, const struct timespec64 *ts); 158 int (*enable)(struct ptp_clock_info *ptp, 159 struct ptp_clock_request *request, int on); 160 int (*verify)(struct ptp_clock_info *ptp, unsigned int pin, 161 enum ptp_pin_function func, unsigned int chan); 162 long (*do_aux_work)(struct ptp_clock_info *ptp); 163 }; 164 165 struct ptp_clock; 166 167 enum ptp_clock_events { 168 PTP_CLOCK_ALARM, 169 PTP_CLOCK_EXTTS, 170 PTP_CLOCK_PPS, 171 PTP_CLOCK_PPSUSR, 172 }; 173 174 /** 175 * struct ptp_clock_event - decribes a PTP hardware clock event 176 * 177 * @type: One of the ptp_clock_events enumeration values. 178 * @index: Identifies the source of the event. 179 * @timestamp: When the event occurred (%PTP_CLOCK_EXTTS only). 180 * @pps_times: When the event occurred (%PTP_CLOCK_PPSUSR only). 181 */ 182 183 struct ptp_clock_event { 184 int type; 185 int index; 186 union { 187 u64 timestamp; 188 struct pps_event_time pps_times; 189 }; 190 }; 191 192 /** 193 * scaled_ppm_to_ppb() - convert scaled ppm to ppb 194 * 195 * @ppm: Parts per million, but with a 16 bit binary fractional field 196 */ 197 static inline long scaled_ppm_to_ppb(long ppm) 198 { 199 /* 200 * The 'freq' field in the 'struct timex' is in parts per 201 * million, but with a 16 bit binary fractional field. 202 * 203 * We want to calculate 204 * 205 * ppb = scaled_ppm * 1000 / 2^16 206 * 207 * which simplifies to 208 * 209 * ppb = scaled_ppm * 125 / 2^13 210 */ 211 s64 ppb = 1 + ppm; 212 213 ppb *= 125; 214 ppb >>= 13; 215 return (long)ppb; 216 } 217 218 #if IS_REACHABLE(CONFIG_PTP_1588_CLOCK) 219 220 /** 221 * ptp_clock_register() - register a PTP hardware clock driver 222 * 223 * @info: Structure describing the new clock. 224 * @parent: Pointer to the parent device of the new clock. 225 * 226 * Returns a valid pointer on success or PTR_ERR on failure. If PHC 227 * support is missing at the configuration level, this function 228 * returns NULL, and drivers are expected to gracefully handle that 229 * case separately. 230 */ 231 232 extern struct ptp_clock *ptp_clock_register(struct ptp_clock_info *info, 233 struct device *parent); 234 235 /** 236 * ptp_clock_unregister() - unregister a PTP hardware clock driver 237 * 238 * @ptp: The clock to remove from service. 239 */ 240 241 extern int ptp_clock_unregister(struct ptp_clock *ptp); 242 243 /** 244 * ptp_clock_event() - notify the PTP layer about an event 245 * 246 * @ptp: The clock obtained from ptp_clock_register(). 247 * @event: Message structure describing the event. 248 */ 249 250 extern void ptp_clock_event(struct ptp_clock *ptp, 251 struct ptp_clock_event *event); 252 253 /** 254 * ptp_clock_index() - obtain the device index of a PTP clock 255 * 256 * @ptp: The clock obtained from ptp_clock_register(). 257 */ 258 259 extern int ptp_clock_index(struct ptp_clock *ptp); 260 261 /** 262 * ptp_find_pin() - obtain the pin index of a given auxiliary function 263 * 264 * The caller must hold ptp_clock::pincfg_mux. Drivers do not have 265 * access to that mutex as ptp_clock is an opaque type. However, the 266 * core code acquires the mutex before invoking the driver's 267 * ptp_clock_info::enable() callback, and so drivers may call this 268 * function from that context. 269 * 270 * @ptp: The clock obtained from ptp_clock_register(). 271 * @func: One of the ptp_pin_function enumerated values. 272 * @chan: The particular functional channel to find. 273 * Return: Pin index in the range of zero to ptp_clock_caps.n_pins - 1, 274 * or -1 if the auxiliary function cannot be found. 275 */ 276 277 int ptp_find_pin(struct ptp_clock *ptp, 278 enum ptp_pin_function func, unsigned int chan); 279 280 /** 281 * ptp_find_pin_unlocked() - wrapper for ptp_find_pin() 282 * 283 * This function acquires the ptp_clock::pincfg_mux mutex before 284 * invoking ptp_find_pin(). Instead of using this function, drivers 285 * should most likely call ptp_find_pin() directly from their 286 * ptp_clock_info::enable() method. 287 * 288 */ 289 290 int ptp_find_pin_unlocked(struct ptp_clock *ptp, 291 enum ptp_pin_function func, unsigned int chan); 292 293 /** 294 * ptp_schedule_worker() - schedule ptp auxiliary work 295 * 296 * @ptp: The clock obtained from ptp_clock_register(). 297 * @delay: number of jiffies to wait before queuing 298 * See kthread_queue_delayed_work() for more info. 299 */ 300 301 int ptp_schedule_worker(struct ptp_clock *ptp, unsigned long delay); 302 303 /** 304 * ptp_cancel_worker_sync() - cancel ptp auxiliary clock 305 * 306 * @ptp: The clock obtained from ptp_clock_register(). 307 */ 308 void ptp_cancel_worker_sync(struct ptp_clock *ptp); 309 310 /** 311 * ptp_get_vclocks_index() - get all vclocks index on pclock, and 312 * caller is responsible to free memory 313 * of vclock_index 314 * 315 * @pclock_index: phc index of ptp pclock. 316 * @vclock_index: pointer to pointer of vclock index. 317 * 318 * return number of vclocks. 319 */ 320 int ptp_get_vclocks_index(int pclock_index, int **vclock_index); 321 322 /** 323 * ptp_convert_timestamp() - convert timestamp to a ptp vclock time 324 * 325 * @hwtstamps: skb_shared_hwtstamps structure pointer 326 * @vclock_index: phc index of ptp vclock. 327 */ 328 void ptp_convert_timestamp(struct skb_shared_hwtstamps *hwtstamps, 329 int vclock_index); 330 331 #else 332 static inline struct ptp_clock *ptp_clock_register(struct ptp_clock_info *info, 333 struct device *parent) 334 { return NULL; } 335 static inline int ptp_clock_unregister(struct ptp_clock *ptp) 336 { return 0; } 337 static inline void ptp_clock_event(struct ptp_clock *ptp, 338 struct ptp_clock_event *event) 339 { } 340 static inline int ptp_clock_index(struct ptp_clock *ptp) 341 { return -1; } 342 static inline int ptp_find_pin(struct ptp_clock *ptp, 343 enum ptp_pin_function func, unsigned int chan) 344 { return -1; } 345 static inline int ptp_schedule_worker(struct ptp_clock *ptp, 346 unsigned long delay) 347 { return -EOPNOTSUPP; } 348 static inline void ptp_cancel_worker_sync(struct ptp_clock *ptp) 349 { } 350 static inline int ptp_get_vclocks_index(int pclock_index, int **vclock_index) 351 { return 0; } 352 static inline void ptp_convert_timestamp(struct skb_shared_hwtstamps *hwtstamps, 353 int vclock_index) 354 { } 355 356 #endif 357 358 static inline void ptp_read_system_prets(struct ptp_system_timestamp *sts) 359 { 360 if (sts) 361 ktime_get_real_ts64(&sts->pre_ts); 362 } 363 364 static inline void ptp_read_system_postts(struct ptp_system_timestamp *sts) 365 { 366 if (sts) 367 ktime_get_real_ts64(&sts->post_ts); 368 } 369 370 #endif 371