1 /* linux/include/linux/clockchips.h 2 * 3 * This file contains the structure definitions for clockchips. 4 * 5 * If you are not a clockchip, or the time of day code, you should 6 * not be including this file! 7 */ 8 #ifndef _LINUX_CLOCKCHIPS_H 9 #define _LINUX_CLOCKCHIPS_H 10 11 /* Clock event notification values */ 12 enum clock_event_nofitiers { 13 CLOCK_EVT_NOTIFY_ADD, 14 CLOCK_EVT_NOTIFY_BROADCAST_ON, 15 CLOCK_EVT_NOTIFY_BROADCAST_OFF, 16 CLOCK_EVT_NOTIFY_BROADCAST_FORCE, 17 CLOCK_EVT_NOTIFY_BROADCAST_ENTER, 18 CLOCK_EVT_NOTIFY_BROADCAST_EXIT, 19 CLOCK_EVT_NOTIFY_SUSPEND, 20 CLOCK_EVT_NOTIFY_RESUME, 21 CLOCK_EVT_NOTIFY_CPU_DYING, 22 CLOCK_EVT_NOTIFY_CPU_DEAD, 23 }; 24 25 #ifdef CONFIG_GENERIC_CLOCKEVENTS_BUILD 26 27 #include <linux/clocksource.h> 28 #include <linux/cpumask.h> 29 #include <linux/ktime.h> 30 #include <linux/notifier.h> 31 32 struct clock_event_device; 33 struct module; 34 35 /* Clock event mode commands */ 36 enum clock_event_mode { 37 CLOCK_EVT_MODE_UNUSED = 0, 38 CLOCK_EVT_MODE_SHUTDOWN, 39 CLOCK_EVT_MODE_PERIODIC, 40 CLOCK_EVT_MODE_ONESHOT, 41 CLOCK_EVT_MODE_RESUME, 42 }; 43 44 /* 45 * Clock event features 46 */ 47 #define CLOCK_EVT_FEAT_PERIODIC 0x000001 48 #define CLOCK_EVT_FEAT_ONESHOT 0x000002 49 #define CLOCK_EVT_FEAT_KTIME 0x000004 50 /* 51 * x86(64) specific misfeatures: 52 * 53 * - Clockevent source stops in C3 State and needs broadcast support. 54 * - Local APIC timer is used as a dummy device. 55 */ 56 #define CLOCK_EVT_FEAT_C3STOP 0x000008 57 #define CLOCK_EVT_FEAT_DUMMY 0x000010 58 59 /* 60 * Core shall set the interrupt affinity dynamically in broadcast mode 61 */ 62 #define CLOCK_EVT_FEAT_DYNIRQ 0x000020 63 #define CLOCK_EVT_FEAT_PERCPU 0x000040 64 65 /* 66 * Clockevent device is based on a hrtimer for broadcast 67 */ 68 #define CLOCK_EVT_FEAT_HRTIMER 0x000080 69 70 /** 71 * struct clock_event_device - clock event device descriptor 72 * @event_handler: Assigned by the framework to be called by the low 73 * level handler of the event source 74 * @set_next_event: set next event function using a clocksource delta 75 * @set_next_ktime: set next event function using a direct ktime value 76 * @next_event: local storage for the next event in oneshot mode 77 * @max_delta_ns: maximum delta value in ns 78 * @min_delta_ns: minimum delta value in ns 79 * @mult: nanosecond to cycles multiplier 80 * @shift: nanoseconds to cycles divisor (power of two) 81 * @mode: operating mode assigned by the management code 82 * @features: features 83 * @retries: number of forced programming retries 84 * @set_mode: set mode function 85 * @broadcast: function to broadcast events 86 * @min_delta_ticks: minimum delta value in ticks stored for reconfiguration 87 * @max_delta_ticks: maximum delta value in ticks stored for reconfiguration 88 * @name: ptr to clock event name 89 * @rating: variable to rate clock event devices 90 * @irq: IRQ number (only for non CPU local devices) 91 * @bound_on: Bound on CPU 92 * @cpumask: cpumask to indicate for which CPUs this device works 93 * @list: list head for the management code 94 * @owner: module reference 95 */ 96 struct clock_event_device { 97 void (*event_handler)(struct clock_event_device *); 98 int (*set_next_event)(unsigned long evt, 99 struct clock_event_device *); 100 int (*set_next_ktime)(ktime_t expires, 101 struct clock_event_device *); 102 ktime_t next_event; 103 u64 max_delta_ns; 104 u64 min_delta_ns; 105 u32 mult; 106 u32 shift; 107 enum clock_event_mode mode; 108 unsigned int features; 109 unsigned long retries; 110 111 void (*broadcast)(const struct cpumask *mask); 112 void (*set_mode)(enum clock_event_mode mode, 113 struct clock_event_device *); 114 void (*suspend)(struct clock_event_device *); 115 void (*resume)(struct clock_event_device *); 116 unsigned long min_delta_ticks; 117 unsigned long max_delta_ticks; 118 119 const char *name; 120 int rating; 121 int irq; 122 int bound_on; 123 const struct cpumask *cpumask; 124 struct list_head list; 125 struct module *owner; 126 } ____cacheline_aligned; 127 128 /* 129 * Calculate a multiplication factor for scaled math, which is used to convert 130 * nanoseconds based values to clock ticks: 131 * 132 * clock_ticks = (nanoseconds * factor) >> shift. 133 * 134 * div_sc is the rearranged equation to calculate a factor from a given clock 135 * ticks / nanoseconds ratio: 136 * 137 * factor = (clock_ticks << shift) / nanoseconds 138 */ 139 static inline unsigned long div_sc(unsigned long ticks, unsigned long nsec, 140 int shift) 141 { 142 uint64_t tmp = ((uint64_t)ticks) << shift; 143 144 do_div(tmp, nsec); 145 return (unsigned long) tmp; 146 } 147 148 /* Clock event layer functions */ 149 extern u64 clockevent_delta2ns(unsigned long latch, 150 struct clock_event_device *evt); 151 extern void clockevents_register_device(struct clock_event_device *dev); 152 extern int clockevents_unbind_device(struct clock_event_device *ced, int cpu); 153 154 extern void clockevents_config(struct clock_event_device *dev, u32 freq); 155 extern void clockevents_config_and_register(struct clock_event_device *dev, 156 u32 freq, unsigned long min_delta, 157 unsigned long max_delta); 158 159 extern int clockevents_update_freq(struct clock_event_device *ce, u32 freq); 160 161 extern void clockevents_exchange_device(struct clock_event_device *old, 162 struct clock_event_device *new); 163 extern void clockevents_set_mode(struct clock_event_device *dev, 164 enum clock_event_mode mode); 165 extern int clockevents_program_event(struct clock_event_device *dev, 166 ktime_t expires, bool force); 167 168 extern void clockevents_handle_noop(struct clock_event_device *dev); 169 170 static inline void 171 clockevents_calc_mult_shift(struct clock_event_device *ce, u32 freq, u32 minsec) 172 { 173 return clocks_calc_mult_shift(&ce->mult, &ce->shift, NSEC_PER_SEC, 174 freq, minsec); 175 } 176 177 extern void clockevents_suspend(void); 178 extern void clockevents_resume(void); 179 180 #ifdef CONFIG_GENERIC_CLOCKEVENTS_BROADCAST 181 #ifdef CONFIG_ARCH_HAS_TICK_BROADCAST 182 extern void tick_broadcast(const struct cpumask *mask); 183 #else 184 #define tick_broadcast NULL 185 #endif 186 extern int tick_receive_broadcast(void); 187 #endif 188 189 #if defined(CONFIG_GENERIC_CLOCKEVENTS_BROADCAST) && defined(CONFIG_TICK_ONESHOT) 190 extern void tick_setup_hrtimer_broadcast(void); 191 extern int tick_check_broadcast_expired(void); 192 #else 193 static inline int tick_check_broadcast_expired(void) { return 0; } 194 static inline void tick_setup_hrtimer_broadcast(void) {}; 195 #endif 196 197 #ifdef CONFIG_GENERIC_CLOCKEVENTS 198 extern int clockevents_notify(unsigned long reason, void *arg); 199 #else 200 static inline int clockevents_notify(unsigned long reason, void *arg) { return 0; } 201 #endif 202 203 #else /* CONFIG_GENERIC_CLOCKEVENTS_BUILD */ 204 205 static inline void clockevents_suspend(void) {} 206 static inline void clockevents_resume(void) {} 207 208 static inline int clockevents_notify(unsigned long reason, void *arg) { return 0; } 209 static inline int tick_check_broadcast_expired(void) { return 0; } 210 static inline void tick_setup_hrtimer_broadcast(void) {}; 211 212 #endif 213 214 #endif 215