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 64 /** 65 * struct clock_event_device - clock event device descriptor 66 * @event_handler: Assigned by the framework to be called by the low 67 * level handler of the event source 68 * @set_next_event: set next event function using a clocksource delta 69 * @set_next_ktime: set next event function using a direct ktime value 70 * @next_event: local storage for the next event in oneshot mode 71 * @max_delta_ns: maximum delta value in ns 72 * @min_delta_ns: minimum delta value in ns 73 * @mult: nanosecond to cycles multiplier 74 * @shift: nanoseconds to cycles divisor (power of two) 75 * @mode: operating mode assigned by the management code 76 * @features: features 77 * @retries: number of forced programming retries 78 * @set_mode: set mode function 79 * @broadcast: function to broadcast events 80 * @min_delta_ticks: minimum delta value in ticks stored for reconfiguration 81 * @max_delta_ticks: maximum delta value in ticks stored for reconfiguration 82 * @name: ptr to clock event name 83 * @rating: variable to rate clock event devices 84 * @irq: IRQ number (only for non CPU local devices) 85 * @cpumask: cpumask to indicate for which CPUs this device works 86 * @list: list head for the management code 87 * @owner: module reference 88 */ 89 struct clock_event_device { 90 void (*event_handler)(struct clock_event_device *); 91 int (*set_next_event)(unsigned long evt, 92 struct clock_event_device *); 93 int (*set_next_ktime)(ktime_t expires, 94 struct clock_event_device *); 95 ktime_t next_event; 96 u64 max_delta_ns; 97 u64 min_delta_ns; 98 u32 mult; 99 u32 shift; 100 enum clock_event_mode mode; 101 unsigned int features; 102 unsigned long retries; 103 104 void (*broadcast)(const struct cpumask *mask); 105 void (*set_mode)(enum clock_event_mode mode, 106 struct clock_event_device *); 107 void (*suspend)(struct clock_event_device *); 108 void (*resume)(struct clock_event_device *); 109 unsigned long min_delta_ticks; 110 unsigned long max_delta_ticks; 111 112 const char *name; 113 int rating; 114 int irq; 115 const struct cpumask *cpumask; 116 struct list_head list; 117 struct module *owner; 118 } ____cacheline_aligned; 119 120 /* 121 * Calculate a multiplication factor for scaled math, which is used to convert 122 * nanoseconds based values to clock ticks: 123 * 124 * clock_ticks = (nanoseconds * factor) >> shift. 125 * 126 * div_sc is the rearranged equation to calculate a factor from a given clock 127 * ticks / nanoseconds ratio: 128 * 129 * factor = (clock_ticks << shift) / nanoseconds 130 */ 131 static inline unsigned long div_sc(unsigned long ticks, unsigned long nsec, 132 int shift) 133 { 134 uint64_t tmp = ((uint64_t)ticks) << shift; 135 136 do_div(tmp, nsec); 137 return (unsigned long) tmp; 138 } 139 140 /* Clock event layer functions */ 141 extern u64 clockevent_delta2ns(unsigned long latch, 142 struct clock_event_device *evt); 143 extern void clockevents_register_device(struct clock_event_device *dev); 144 extern int clockevents_unbind_device(struct clock_event_device *ced, int cpu); 145 146 extern void clockevents_config(struct clock_event_device *dev, u32 freq); 147 extern void clockevents_config_and_register(struct clock_event_device *dev, 148 u32 freq, unsigned long min_delta, 149 unsigned long max_delta); 150 151 extern int clockevents_update_freq(struct clock_event_device *ce, u32 freq); 152 153 extern void clockevents_exchange_device(struct clock_event_device *old, 154 struct clock_event_device *new); 155 extern void clockevents_set_mode(struct clock_event_device *dev, 156 enum clock_event_mode mode); 157 extern int clockevents_program_event(struct clock_event_device *dev, 158 ktime_t expires, bool force); 159 160 extern void clockevents_handle_noop(struct clock_event_device *dev); 161 162 static inline void 163 clockevents_calc_mult_shift(struct clock_event_device *ce, u32 freq, u32 minsec) 164 { 165 return clocks_calc_mult_shift(&ce->mult, &ce->shift, NSEC_PER_SEC, 166 freq, minsec); 167 } 168 169 extern void clockevents_suspend(void); 170 extern void clockevents_resume(void); 171 172 #ifdef CONFIG_GENERIC_CLOCKEVENTS_BROADCAST 173 #ifdef CONFIG_ARCH_HAS_TICK_BROADCAST 174 extern void tick_broadcast(const struct cpumask *mask); 175 #else 176 #define tick_broadcast NULL 177 #endif 178 extern int tick_receive_broadcast(void); 179 #endif 180 181 #if defined(CONFIG_GENERIC_CLOCKEVENTS_BROADCAST) && defined(CONFIG_TICK_ONESHOT) 182 extern int tick_check_broadcast_expired(void); 183 #else 184 static inline int tick_check_broadcast_expired(void) { return 0; } 185 #endif 186 187 #ifdef CONFIG_GENERIC_CLOCKEVENTS 188 extern void clockevents_notify(unsigned long reason, void *arg); 189 #else 190 static inline void clockevents_notify(unsigned long reason, void *arg) {} 191 #endif 192 193 #else /* CONFIG_GENERIC_CLOCKEVENTS_BUILD */ 194 195 static inline void clockevents_suspend(void) {} 196 static inline void clockevents_resume(void) {} 197 198 static inline void clockevents_notify(unsigned long reason, void *arg) {} 199 static inline int tick_check_broadcast_expired(void) { return 0; } 200 201 #endif 202 203 #endif 204