1 /* SPDX-License-Identifier: GPL-2.0-or-later */ 2 /* 3 * PTP 1588 clock support - private declarations for the core module. 4 * 5 * Copyright (C) 2010 OMICRON electronics GmbH 6 */ 7 #ifndef _PTP_PRIVATE_H_ 8 #define _PTP_PRIVATE_H_ 9 10 #include <linux/cdev.h> 11 #include <linux/device.h> 12 #include <linux/kthread.h> 13 #include <linux/mutex.h> 14 #include <linux/posix-clock.h> 15 #include <linux/ptp_clock.h> 16 #include <linux/ptp_clock_kernel.h> 17 #include <linux/time.h> 18 #include <linux/list.h> 19 #include <linux/bitmap.h> 20 #include <linux/debugfs.h> 21 22 #define PTP_MAX_TIMESTAMPS 128 23 #define PTP_BUF_TIMESTAMPS 30 24 #define PTP_DEFAULT_MAX_VCLOCKS 20 25 #define PTP_MAX_VCLOCKS_LIMIT (KMALLOC_MAX_SIZE/(sizeof(int))) 26 #define PTP_MAX_CHANNELS 2048 27 28 enum { 29 PTP_LOCK_PHYSICAL = 0, 30 PTP_LOCK_VIRTUAL, 31 }; 32 33 struct timestamp_event_queue { 34 struct ptp_extts_event buf[PTP_MAX_TIMESTAMPS]; 35 int head; 36 int tail; 37 spinlock_t lock; 38 struct list_head qlist; 39 unsigned long *mask; 40 struct dentry *debugfs_instance; 41 struct debugfs_u32_array dfs_bitmap; 42 }; 43 44 struct ptp_clock { 45 struct posix_clock clock; 46 struct device dev; 47 struct ptp_clock_info *info; 48 dev_t devid; 49 int index; /* index into clocks.map */ 50 struct pps_device *pps_source; 51 long dialed_frequency; /* remembers the frequency adjustment */ 52 struct list_head tsevqs; /* timestamp fifo list */ 53 spinlock_t tsevqs_lock; /* protects tsevqs from concurrent access */ 54 struct mutex pincfg_mux; /* protect concurrent info->pin_config access */ 55 wait_queue_head_t tsev_wq; 56 int defunct; /* tells readers to go away when clock is being removed */ 57 struct device_attribute *pin_dev_attr; 58 struct attribute **pin_attr; 59 struct attribute_group pin_attr_group; 60 /* 1st entry is a pointer to the real group, 2nd is NULL terminator */ 61 const struct attribute_group *pin_attr_groups[2]; 62 struct kthread_worker *kworker; 63 struct kthread_delayed_work aux_work; 64 unsigned int max_vclocks; 65 unsigned int n_vclocks; 66 int *vclock_index; 67 struct mutex n_vclocks_mux; /* protect concurrent n_vclocks access */ 68 bool is_virtual_clock; 69 bool has_cycles; 70 struct dentry *debugfs_root; 71 }; 72 73 #define info_to_vclock(d) container_of((d), struct ptp_vclock, info) 74 #define cc_to_vclock(d) container_of((d), struct ptp_vclock, cc) 75 #define dw_to_vclock(d) container_of((d), struct ptp_vclock, refresh_work) 76 77 struct ptp_vclock { 78 struct ptp_clock *pclock; 79 struct ptp_clock_info info; 80 struct ptp_clock *clock; 81 struct hlist_node vclock_hash_node; 82 struct cyclecounter cc; 83 struct timecounter tc; 84 struct mutex lock; /* protects tc/cc */ 85 }; 86 87 /* 88 * The function queue_cnt() is safe for readers to call without 89 * holding q->lock. Readers use this function to verify that the queue 90 * is nonempty before proceeding with a dequeue operation. The fact 91 * that a writer might concurrently increment the tail does not 92 * matter, since the queue remains nonempty nonetheless. 93 */ 94 static inline int queue_cnt(const struct timestamp_event_queue *q) 95 { 96 /* 97 * Paired with WRITE_ONCE() in enqueue_external_timestamp(), 98 * ptp_read(), extts_fifo_show(). 99 */ 100 int cnt = READ_ONCE(q->tail) - READ_ONCE(q->head); 101 return cnt < 0 ? PTP_MAX_TIMESTAMPS + cnt : cnt; 102 } 103 104 /* Check if ptp virtual clock is in use */ 105 static inline bool ptp_vclock_in_use(struct ptp_clock *ptp) 106 { 107 bool in_use = false; 108 109 /* Virtual clocks can't be stacked on top of virtual clocks. 110 * Avoid acquiring the n_vclocks_mux on virtual clocks, to allow this 111 * function to be called from code paths where the n_vclocks_mux of the 112 * parent physical clock is already held. Functionally that's not an 113 * issue, but lockdep would complain, because they have the same lock 114 * class. 115 */ 116 if (ptp->is_virtual_clock) 117 return false; 118 119 if (mutex_lock_interruptible(&ptp->n_vclocks_mux)) 120 return true; 121 122 if (ptp->n_vclocks) 123 in_use = true; 124 125 mutex_unlock(&ptp->n_vclocks_mux); 126 127 return in_use; 128 } 129 130 /* Check if ptp clock shall be free running */ 131 static inline bool ptp_clock_freerun(struct ptp_clock *ptp) 132 { 133 if (ptp->has_cycles) 134 return false; 135 136 return ptp_vclock_in_use(ptp); 137 } 138 139 extern const struct class ptp_class; 140 141 /* 142 * see ptp_chardev.c 143 */ 144 145 void ptp_disable_all_events(struct ptp_clock *ptp); 146 147 /* caller must hold pincfg_mux */ 148 int ptp_set_pinfunc(struct ptp_clock *ptp, unsigned int pin, 149 enum ptp_pin_function func, unsigned int chan); 150 151 long ptp_ioctl(struct posix_clock_context *pccontext, unsigned int cmd, 152 unsigned long arg); 153 154 int ptp_open(struct posix_clock_context *pccontext, fmode_t fmode); 155 156 int ptp_release(struct posix_clock_context *pccontext); 157 158 ssize_t ptp_read(struct posix_clock_context *pccontext, uint flags, char __user *buf, 159 size_t cnt); 160 161 __poll_t ptp_poll(struct posix_clock_context *pccontext, struct file *fp, 162 poll_table *wait); 163 164 /* 165 * see ptp_sysfs.c 166 */ 167 168 extern const struct attribute_group *ptp_groups[]; 169 170 int ptp_populate_pin_groups(struct ptp_clock *ptp); 171 void ptp_cleanup_pin_groups(struct ptp_clock *ptp); 172 173 struct ptp_vclock *ptp_vclock_register(struct ptp_clock *pclock); 174 void ptp_vclock_unregister(struct ptp_vclock *vclock); 175 #endif 176