diff options
Diffstat (limited to 'include/linux/ptp_clock_kernel.h')
| -rw-r--r-- | include/linux/ptp_clock_kernel.h | 453 |
1 files changed, 408 insertions, 45 deletions
diff --git a/include/linux/ptp_clock_kernel.h b/include/linux/ptp_clock_kernel.h index 38a993508327..884364596dd3 100644 --- a/include/linux/ptp_clock_kernel.h +++ b/include/linux/ptp_clock_kernel.h @@ -1,21 +1,8 @@ +/* SPDX-License-Identifier: GPL-2.0-or-later */ /* * PTP 1588 clock support * * Copyright (C) 2010 OMICRON electronics GmbH - * - * This program is free software; you can redistribute it and/or modify - * it under the terms of the GNU General Public License as published by - * the Free Software Foundation; either version 2 of the License, or - * (at your option) any later version. - * - * This program is distributed in the hope that it will be useful, - * but WITHOUT ANY WARRANTY; without even the implied warranty of - * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the - * GNU General Public License for more details. - * - * You should have received a copy of the GNU General Public License - * along with this program; if not, write to the Free Software - * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. */ #ifndef _PTP_CLOCK_KERNEL_H_ @@ -24,7 +11,23 @@ #include <linux/device.h> #include <linux/pps_kernel.h> #include <linux/ptp_clock.h> +#include <linux/timecounter.h> +#include <linux/skbuff.h> +#define PTP_CLOCK_NAME_LEN 32 +/** + * struct ptp_clock_request - request PTP clock event + * + * @type: The type of the request. + * EXTTS: Configure external trigger timestamping + * PEROUT: Configure periodic output signal (e.g. PPS) + * PPS: trigger internal PPS event for input + * into kernel PPS subsystem + * @extts: describes configuration for external trigger timestamping. + * This is only valid when event == PTP_CLK_REQ_EXTTS. + * @perout: describes configuration for periodic output. + * This is only valid when event == PTP_CLK_REQ_PEROUT. + */ struct ptp_clock_request { enum { @@ -38,8 +41,22 @@ struct ptp_clock_request { }; }; +struct system_device_crosststamp; + /** - * struct ptp_clock_info - decribes a PTP hardware clock + * struct ptp_system_timestamp - system time corresponding to a PHC timestamp + * @pre_ts: system timestamp before capturing PHC + * @post_ts: system timestamp after capturing PHC + * @clockid: clock-base used for capturing the system timestamps + */ +struct ptp_system_timestamp { + struct timespec64 pre_ts; + struct timespec64 post_ts; + clockid_t clockid; +}; + +/** + * struct ptp_clock_info - describes a PTP hardware clock * * @owner: The clock driver should set to THIS_MODULE. * @name: A short "friendly name" to identify the clock and to @@ -49,27 +66,122 @@ struct ptp_clock_request { * @n_alarm: The number of programmable alarms. * @n_ext_ts: The number of external time stamp channels. * @n_per_out: The number of programmable periodic signals. + * @n_pins: The number of programmable pins. + * @n_per_lp: The number of channels that support loopback the periodic + * output signal. * @pps: Indicates whether the clock supports a PPS callback. * + * @supported_perout_flags: The set of flags the driver supports for the + * PTP_PEROUT_REQUEST ioctl. The PTP core will + * reject a request with any flag not specified + * here. + * + * @supported_extts_flags: The set of flags the driver supports for the + * PTP_EXTTS_REQUEST ioctl. The PTP core will use + * this list to reject unsupported requests. + * PTP_ENABLE_FEATURE is assumed and does not need to + * be included. If PTP_STRICT_FLAGS is *not* set, + * then both PTP_RISING_EDGE and PTP_FALLING_EDGE + * will be assumed. Note that PTP_STRICT_FLAGS must + * be set if the drivers wants to honor + * PTP_EXTTS_REQUEST2 and any future flags. + * + * @pin_config: Array of length 'n_pins'. If the number of + * programmable pins is nonzero, then drivers must + * allocate and initialize this array. + * * clock operations * - * @adjfreq: Adjusts the frequency of the hardware clock. - * parameter delta: Desired frequency offset from nominal frequency - * in parts per billion + * @adjfine: Adjusts the frequency of the hardware clock. + * parameter scaled_ppm: Desired frequency offset from + * nominal frequency in parts per million, but with a + * 16 bit binary fractional field. + * + * @adjphase: Indicates that the PHC should use an internal servo + * algorithm to correct the provided phase offset. + * parameter delta: PHC servo phase adjustment target + * in nanoseconds. + * + * @getmaxphase: Advertises maximum offset that can be provided + * to the hardware clock's phase control functionality + * through adjphase. * * @adjtime: Shifts the time of the hardware clock. * parameter delta: Desired change in nanoseconds. * - * @gettime: Reads the current time from the hardware clock. - * parameter ts: Holds the result. + * @gettime64: Reads the current time from the hardware clock. + * This method is deprecated. New drivers should implement + * the @gettimex64 method instead. + * parameter ts: Holds the result. + * + * @gettimex64: Reads the current time from the hardware clock and optionally + * also the system clock. + * parameter ts: Holds the PHC timestamp. + * parameter sts: If not NULL, it holds a pair of timestamps from + * the system clock. The first reading is made right before + * reading the lowest bits of the PHC timestamp and the second + * reading immediately follows that. * - * @settime: Set the current time on the hardware clock. - * parameter ts: Time value to set. + * @getcrosststamp: Reads the current time from the hardware clock and + * system clock simultaneously. + * parameter cts: Contains timestamp (device,system) pair, + * where system time is realtime and monotonic. + * + * @settime64: Set the current time on the hardware clock. + * parameter ts: Time value to set. + * + * @getcycles64: Reads the current free running cycle counter from the hardware + * clock. + * If @getcycles64 and @getcyclesx64 are not supported, then + * @gettime64 or @gettimex64 will be used as default + * implementation. + * parameter ts: Holds the result. + * + * @getcyclesx64: Reads the current free running cycle counter from the + * hardware clock and optionally also the system clock. + * If @getcycles64 and @getcyclesx64 are not supported, then + * @gettimex64 will be used as default implementation if + * available. + * parameter ts: Holds the PHC timestamp. + * parameter sts: If not NULL, it holds a pair of timestamps + * from the system clock. The first reading is made right before + * reading the lowest bits of the PHC timestamp and the second + * reading immediately follows that. + * + * @getcrosscycles: Reads the current free running cycle counter from the + * hardware clock and system clock simultaneously. + * If @getcycles64 and @getcyclesx64 are not supported, then + * @getcrosststamp will be used as default implementation if + * available. + * parameter cts: Contains timestamp (device,system) pair, + * where system time is realtime and monotonic. * * @enable: Request driver to enable or disable an ancillary feature. * parameter request: Desired resource to enable or disable. * parameter on: Caller passes one to enable or zero to disable. * + * @verify: Confirm that a pin can perform a given function. The PTP + * Hardware Clock subsystem maintains the 'pin_config' + * array on behalf of the drivers, but the PHC subsystem + * assumes that every pin can perform every function. This + * hook gives drivers a way of telling the core about + * limitations on specific pins. This function must return + * zero if the function can be assigned to this pin, and + * nonzero otherwise. + * parameter pin: index of the pin in question. + * parameter func: the desired function to use. + * parameter chan: the function channel index to use. + * + * @do_aux_work: Request driver to perform auxiliary (periodic) operations + * Driver should return delay of the next auxiliary work + * scheduling time (>=0) or negative value in case further + * scheduling is not required. + * + * @perout_loopback: Request driver to enable or disable the periodic output + * signal loopback. + * parameter index: index of the periodic output signal channel. + * parameter on: caller passes one to enable or zero to disable. + * * Drivers should embed their ptp_clock_info within a private * structure, obtaining a reference to it using container_of(). * @@ -78,44 +190,47 @@ struct ptp_clock_request { struct ptp_clock_info { struct module *owner; - char name[16]; + char name[PTP_CLOCK_NAME_LEN]; s32 max_adj; int n_alarm; int n_ext_ts; int n_per_out; + int n_pins; + int n_per_lp; int pps; - int (*adjfreq)(struct ptp_clock_info *ptp, s32 delta); + unsigned int supported_perout_flags; + unsigned int supported_extts_flags; + struct ptp_pin_desc *pin_config; + int (*adjfine)(struct ptp_clock_info *ptp, long scaled_ppm); + int (*adjphase)(struct ptp_clock_info *ptp, s32 phase); + s32 (*getmaxphase)(struct ptp_clock_info *ptp); int (*adjtime)(struct ptp_clock_info *ptp, s64 delta); - int (*gettime)(struct ptp_clock_info *ptp, struct timespec *ts); - int (*settime)(struct ptp_clock_info *ptp, const struct timespec *ts); + int (*gettime64)(struct ptp_clock_info *ptp, struct timespec64 *ts); + int (*gettimex64)(struct ptp_clock_info *ptp, struct timespec64 *ts, + struct ptp_system_timestamp *sts); + int (*getcrosststamp)(struct ptp_clock_info *ptp, + struct system_device_crosststamp *cts); + int (*settime64)(struct ptp_clock_info *p, const struct timespec64 *ts); + int (*getcycles64)(struct ptp_clock_info *ptp, struct timespec64 *ts); + int (*getcyclesx64)(struct ptp_clock_info *ptp, struct timespec64 *ts, + struct ptp_system_timestamp *sts); + int (*getcrosscycles)(struct ptp_clock_info *ptp, + struct system_device_crosststamp *cts); int (*enable)(struct ptp_clock_info *ptp, struct ptp_clock_request *request, int on); + int (*verify)(struct ptp_clock_info *ptp, unsigned int pin, + enum ptp_pin_function func, unsigned int chan); + long (*do_aux_work)(struct ptp_clock_info *ptp); + int (*perout_loopback)(struct ptp_clock_info *ptp, unsigned int index, + int on); }; struct ptp_clock; -/** - * ptp_clock_register() - register a PTP hardware clock driver - * - * @info: Structure describing the new clock. - * @parent: Pointer to the parent device of the new clock. - */ - -extern struct ptp_clock *ptp_clock_register(struct ptp_clock_info *info, - struct device *parent); - -/** - * ptp_clock_unregister() - unregister a PTP hardware clock driver - * - * @ptp: The clock to remove from service. - */ - -extern int ptp_clock_unregister(struct ptp_clock *ptp); - - enum ptp_clock_events { PTP_CLOCK_ALARM, PTP_CLOCK_EXTTS, + PTP_CLOCK_EXTOFF, PTP_CLOCK_PPS, PTP_CLOCK_PPSUSR, }; @@ -126,6 +241,7 @@ enum ptp_clock_events { * @type: One of the ptp_clock_events enumeration values. * @index: Identifies the source of the event. * @timestamp: When the event occurred (%PTP_CLOCK_EXTTS only). + * @offset: When the event occurred (%PTP_CLOCK_EXTOFF only). * @pps_times: When the event occurred (%PTP_CLOCK_PPSUSR only). */ @@ -134,11 +250,109 @@ struct ptp_clock_event { int index; union { u64 timestamp; + s64 offset; struct pps_event_time pps_times; }; }; /** + * scaled_ppm_to_ppb() - convert scaled ppm to ppb + * + * @ppm: Parts per million, but with a 16 bit binary fractional field + */ +static inline long scaled_ppm_to_ppb(long ppm) +{ + /* + * The 'freq' field in the 'struct timex' is in parts per + * million, but with a 16 bit binary fractional field. + * + * We want to calculate + * + * ppb = scaled_ppm * 1000 / 2^16 + * + * which simplifies to + * + * ppb = scaled_ppm * 125 / 2^13 + */ + s64 ppb = 1 + ppm; + + ppb *= 125; + ppb >>= 13; + return (long)ppb; +} + +/** + * diff_by_scaled_ppm - Calculate difference using scaled ppm + * @base: the base increment value to adjust + * @scaled_ppm: scaled parts per million to adjust by + * @diff: on return, the absolute value of calculated diff + * + * Calculate the difference to adjust the base increment using scaled parts + * per million. + * + * Use mul_u64_u64_div_u64 to perform the difference calculation in avoid + * possible overflow. + * + * Returns: true if scaled_ppm is negative, false otherwise + */ +static inline bool diff_by_scaled_ppm(u64 base, long scaled_ppm, u64 *diff) +{ + bool negative = false; + + if (scaled_ppm < 0) { + negative = true; + scaled_ppm = -scaled_ppm; + } + + *diff = mul_u64_u64_div_u64(base, (u64)scaled_ppm, 1000000ULL << 16); + + return negative; +} + +/** + * adjust_by_scaled_ppm - Adjust a base increment by scaled parts per million + * @base: the base increment value to adjust + * @scaled_ppm: scaled parts per million frequency adjustment + * + * Helper function which calculates a new increment value based on the + * requested scaled parts per million adjustment. + */ +static inline u64 adjust_by_scaled_ppm(u64 base, long scaled_ppm) +{ + u64 diff; + + if (diff_by_scaled_ppm(base, scaled_ppm, &diff)) + return base - diff; + + return base + diff; +} + +#if IS_ENABLED(CONFIG_PTP_1588_CLOCK) + +/** + * ptp_clock_register() - register a PTP hardware clock driver + * + * @info: Structure describing the new clock. + * @parent: Pointer to the parent device of the new clock. + * + * Returns: a valid pointer on success or PTR_ERR on failure. If PHC + * support is missing at the configuration level, this function + * returns NULL, and drivers are expected to gracefully handle that + * case separately. + */ + +extern struct ptp_clock *ptp_clock_register(struct ptp_clock_info *info, + struct device *parent); + +/** + * ptp_clock_unregister() - unregister a PTP hardware clock driver + * + * @ptp: The clock to remove from service. + */ + +extern int ptp_clock_unregister(struct ptp_clock *ptp); + +/** * ptp_clock_event() - notify the PTP layer about an event * * @ptp: The clock obtained from ptp_clock_register(). @@ -156,4 +370,153 @@ extern void ptp_clock_event(struct ptp_clock *ptp, extern int ptp_clock_index(struct ptp_clock *ptp); +/** + * ptp_clock_index_by_of_node() - obtain the device index of + * a PTP clock based on the PTP device of_node + * + * @np: The device of_node pointer of the PTP device. + * Return: The PHC index on success or -1 on failure. + */ +int ptp_clock_index_by_of_node(struct device_node *np); + +/** + * ptp_clock_index_by_dev() - obtain the device index of + * a PTP clock based on the PTP device. + * + * @parent: The parent device (PTP device) pointer of the PTP clock. + * Return: The PHC index on success or -1 on failure. + */ +int ptp_clock_index_by_dev(struct device *parent); + +/** + * ptp_find_pin() - obtain the pin index of a given auxiliary function + * + * The caller must hold ptp_clock::pincfg_mux. Drivers do not have + * access to that mutex as ptp_clock is an opaque type. However, the + * core code acquires the mutex before invoking the driver's + * ptp_clock_info::enable() callback, and so drivers may call this + * function from that context. + * + * @ptp: The clock obtained from ptp_clock_register(). + * @func: One of the ptp_pin_function enumerated values. + * @chan: The particular functional channel to find. + * Return: Pin index in the range of zero to ptp_clock_caps.n_pins - 1, + * or -1 if the auxiliary function cannot be found. + */ + +int ptp_find_pin(struct ptp_clock *ptp, + enum ptp_pin_function func, unsigned int chan); + +/** + * ptp_find_pin_unlocked() - wrapper for ptp_find_pin() + * + * This function acquires the ptp_clock::pincfg_mux mutex before + * invoking ptp_find_pin(). Instead of using this function, drivers + * should most likely call ptp_find_pin() directly from their + * ptp_clock_info::enable() method. + * +* @ptp: The clock obtained from ptp_clock_register(). +* @func: One of the ptp_pin_function enumerated values. +* @chan: The particular functional channel to find. +* Return: Pin index in the range of zero to ptp_clock_caps.n_pins - 1, +* or -1 if the auxiliary function cannot be found. + */ + +int ptp_find_pin_unlocked(struct ptp_clock *ptp, + enum ptp_pin_function func, unsigned int chan); + +/** + * ptp_schedule_worker() - schedule ptp auxiliary work + * + * @ptp: The clock obtained from ptp_clock_register(). + * @delay: number of jiffies to wait before queuing + * See kthread_queue_delayed_work() for more info. + */ + +int ptp_schedule_worker(struct ptp_clock *ptp, unsigned long delay); + +/** + * ptp_cancel_worker_sync() - cancel ptp auxiliary clock + * + * @ptp: The clock obtained from ptp_clock_register(). + */ +void ptp_cancel_worker_sync(struct ptp_clock *ptp); + +#else +static inline struct ptp_clock *ptp_clock_register(struct ptp_clock_info *info, + struct device *parent) +{ return NULL; } +static inline int ptp_clock_unregister(struct ptp_clock *ptp) +{ return 0; } +static inline void ptp_clock_event(struct ptp_clock *ptp, + struct ptp_clock_event *event) +{ } +static inline int ptp_clock_index(struct ptp_clock *ptp) +{ return -1; } +static inline int ptp_clock_index_by_of_node(struct device_node *np) +{ return -1; } +static inline int ptp_clock_index_by_dev(struct device *parent) +{ return -1; } +static inline int ptp_find_pin(struct ptp_clock *ptp, + enum ptp_pin_function func, unsigned int chan) +{ return -1; } +static inline int ptp_find_pin_unlocked(struct ptp_clock *ptp, + enum ptp_pin_function func, + unsigned int chan) +{ return -1; } +static inline int ptp_schedule_worker(struct ptp_clock *ptp, + unsigned long delay) +{ return -EOPNOTSUPP; } +static inline void ptp_cancel_worker_sync(struct ptp_clock *ptp) +{ } +#endif + +#if IS_BUILTIN(CONFIG_PTP_1588_CLOCK) +/* + * These are called by the network core, and don't work if PTP is in + * a loadable module. + */ + +/** + * ptp_get_vclocks_index() - get all vclocks index on pclock, and + * caller is responsible to free memory + * of vclock_index + * + * @pclock_index: phc index of ptp pclock. + * @vclock_index: pointer to pointer of vclock index. + * + * return number of vclocks. + */ +int ptp_get_vclocks_index(int pclock_index, int **vclock_index); + +/** + * ptp_convert_timestamp() - convert timestamp to a ptp vclock time + * + * @hwtstamp: timestamp + * @vclock_index: phc index of ptp vclock. + * + * Returns: converted timestamp, or 0 on error. + */ +ktime_t ptp_convert_timestamp(const ktime_t *hwtstamp, int vclock_index); +#else +static inline int ptp_get_vclocks_index(int pclock_index, int **vclock_index) +{ return 0; } +static inline ktime_t ptp_convert_timestamp(const ktime_t *hwtstamp, + int vclock_index) +{ return 0; } + +#endif + +static inline void ptp_read_system_prets(struct ptp_system_timestamp *sts) +{ + if (sts) + ktime_get_clock_ts64(sts->clockid, &sts->pre_ts); +} + +static inline void ptp_read_system_postts(struct ptp_system_timestamp *sts) +{ + if (sts) + ktime_get_clock_ts64(sts->clockid, &sts->post_ts); +} + #endif |