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 /* Legacy ->set_mode() callback doesn't support below modes */ 44 }; 45 46 /* 47 * Clock event features 48 */ 49 #define CLOCK_EVT_FEAT_PERIODIC 0x000001 50 #define CLOCK_EVT_FEAT_ONESHOT 0x000002 51 #define CLOCK_EVT_FEAT_KTIME 0x000004 52 /* 53 * x86(64) specific misfeatures: 54 * 55 * - Clockevent source stops in C3 State and needs broadcast support. 56 * - Local APIC timer is used as a dummy device. 57 */ 58 #define CLOCK_EVT_FEAT_C3STOP 0x000008 59 #define CLOCK_EVT_FEAT_DUMMY 0x000010 60 61 /* 62 * Core shall set the interrupt affinity dynamically in broadcast mode 63 */ 64 #define CLOCK_EVT_FEAT_DYNIRQ 0x000020 65 #define CLOCK_EVT_FEAT_PERCPU 0x000040 66 67 /* 68 * Clockevent device is based on a hrtimer for broadcast 69 */ 70 #define CLOCK_EVT_FEAT_HRTIMER 0x000080 71 72 /** 73 * struct clock_event_device - clock event device descriptor 74 * @event_handler: Assigned by the framework to be called by the low 75 * level handler of the event source 76 * @set_next_event: set next event function using a clocksource delta 77 * @set_next_ktime: set next event function using a direct ktime value 78 * @next_event: local storage for the next event in oneshot mode 79 * @max_delta_ns: maximum delta value in ns 80 * @min_delta_ns: minimum delta value in ns 81 * @mult: nanosecond to cycles multiplier 82 * @shift: nanoseconds to cycles divisor (power of two) 83 * @mode: operating mode assigned by the management code 84 * @features: features 85 * @retries: number of forced programming retries 86 * @set_mode: legacy set mode function, only for modes <= CLOCK_EVT_MODE_RESUME. 87 * @set_mode_periodic: switch mode to periodic, if !set_mode 88 * @set_mode_oneshot: switch mode to oneshot, if !set_mode 89 * @set_mode_shutdown: switch mode to shutdown, if !set_mode 90 * @tick_resume: resume clkevt device, if !set_mode 91 * @broadcast: function to broadcast events 92 * @min_delta_ticks: minimum delta value in ticks stored for reconfiguration 93 * @max_delta_ticks: maximum delta value in ticks stored for reconfiguration 94 * @name: ptr to clock event name 95 * @rating: variable to rate clock event devices 96 * @irq: IRQ number (only for non CPU local devices) 97 * @bound_on: Bound on CPU 98 * @cpumask: cpumask to indicate for which CPUs this device works 99 * @list: list head for the management code 100 * @owner: module reference 101 */ 102 struct clock_event_device { 103 void (*event_handler)(struct clock_event_device *); 104 int (*set_next_event)(unsigned long evt, 105 struct clock_event_device *); 106 int (*set_next_ktime)(ktime_t expires, 107 struct clock_event_device *); 108 ktime_t next_event; 109 u64 max_delta_ns; 110 u64 min_delta_ns; 111 u32 mult; 112 u32 shift; 113 enum clock_event_mode mode; 114 unsigned int features; 115 unsigned long retries; 116 117 /* 118 * Mode transition callback(s): Only one of the two groups should be 119 * defined: 120 * - set_mode(), only for modes <= CLOCK_EVT_MODE_RESUME. 121 * - set_mode_{shutdown|periodic|oneshot|resume}(). 122 */ 123 void (*set_mode)(enum clock_event_mode mode, 124 struct clock_event_device *); 125 int (*set_mode_periodic)(struct clock_event_device *); 126 int (*set_mode_oneshot)(struct clock_event_device *); 127 int (*set_mode_shutdown)(struct clock_event_device *); 128 int (*tick_resume)(struct clock_event_device *); 129 130 void (*broadcast)(const struct cpumask *mask); 131 void (*suspend)(struct clock_event_device *); 132 void (*resume)(struct clock_event_device *); 133 unsigned long min_delta_ticks; 134 unsigned long max_delta_ticks; 135 136 const char *name; 137 int rating; 138 int irq; 139 int bound_on; 140 const struct cpumask *cpumask; 141 struct list_head list; 142 struct module *owner; 143 } ____cacheline_aligned; 144 145 /* 146 * Calculate a multiplication factor for scaled math, which is used to convert 147 * nanoseconds based values to clock ticks: 148 * 149 * clock_ticks = (nanoseconds * factor) >> shift. 150 * 151 * div_sc is the rearranged equation to calculate a factor from a given clock 152 * ticks / nanoseconds ratio: 153 * 154 * factor = (clock_ticks << shift) / nanoseconds 155 */ 156 static inline unsigned long div_sc(unsigned long ticks, unsigned long nsec, 157 int shift) 158 { 159 uint64_t tmp = ((uint64_t)ticks) << shift; 160 161 do_div(tmp, nsec); 162 return (unsigned long) tmp; 163 } 164 165 /* Clock event layer functions */ 166 extern u64 clockevent_delta2ns(unsigned long latch, 167 struct clock_event_device *evt); 168 extern void clockevents_register_device(struct clock_event_device *dev); 169 extern int clockevents_unbind_device(struct clock_event_device *ced, int cpu); 170 171 extern void clockevents_config(struct clock_event_device *dev, u32 freq); 172 extern void clockevents_config_and_register(struct clock_event_device *dev, 173 u32 freq, unsigned long min_delta, 174 unsigned long max_delta); 175 176 extern int clockevents_update_freq(struct clock_event_device *ce, u32 freq); 177 178 extern void clockevents_exchange_device(struct clock_event_device *old, 179 struct clock_event_device *new); 180 extern void clockevents_set_mode(struct clock_event_device *dev, 181 enum clock_event_mode mode); 182 extern int clockevents_program_event(struct clock_event_device *dev, 183 ktime_t expires, bool force); 184 185 extern void clockevents_handle_noop(struct clock_event_device *dev); 186 187 static inline void 188 clockevents_calc_mult_shift(struct clock_event_device *ce, u32 freq, u32 minsec) 189 { 190 return clocks_calc_mult_shift(&ce->mult, &ce->shift, NSEC_PER_SEC, 191 freq, minsec); 192 } 193 194 extern void clockevents_suspend(void); 195 extern void clockevents_resume(void); 196 197 #ifdef CONFIG_GENERIC_CLOCKEVENTS_BROADCAST 198 #ifdef CONFIG_ARCH_HAS_TICK_BROADCAST 199 extern void tick_broadcast(const struct cpumask *mask); 200 #else 201 #define tick_broadcast NULL 202 #endif 203 extern int tick_receive_broadcast(void); 204 #endif 205 206 #if defined(CONFIG_GENERIC_CLOCKEVENTS_BROADCAST) && defined(CONFIG_TICK_ONESHOT) 207 extern void tick_setup_hrtimer_broadcast(void); 208 extern int tick_check_broadcast_expired(void); 209 #else 210 static inline int tick_check_broadcast_expired(void) { return 0; } 211 static inline void tick_setup_hrtimer_broadcast(void) {}; 212 #endif 213 214 #ifdef CONFIG_GENERIC_CLOCKEVENTS 215 extern int clockevents_notify(unsigned long reason, void *arg); 216 #else 217 static inline int clockevents_notify(unsigned long reason, void *arg) { return 0; } 218 #endif 219 220 #else /* CONFIG_GENERIC_CLOCKEVENTS_BUILD */ 221 222 static inline void clockevents_suspend(void) {} 223 static inline void clockevents_resume(void) {} 224 225 static inline int clockevents_notify(unsigned long reason, void *arg) { return 0; } 226 static inline int tick_check_broadcast_expired(void) { return 0; } 227 static inline void tick_setup_hrtimer_broadcast(void) {}; 228 229 #endif 230 231 #endif 232