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1 : : /* SPDX-License-Identifier: GPL-2.0 */ 2 : : /* linux/include/linux/clockchips.h 3 : : * 4 : : * This file contains the structure definitions for clockchips. 5 : : * 6 : : * If you are not a clockchip, or the time of day code, you should 7 : : * not be including this file! 8 : : */ 9 : : #ifndef _LINUX_CLOCKCHIPS_H 10 : : #define _LINUX_CLOCKCHIPS_H 11 : : 12 : : #ifdef CONFIG_GENERIC_CLOCKEVENTS 13 : : 14 : : # include <linux/clocksource.h> 15 : : # include <linux/cpumask.h> 16 : : # include <linux/ktime.h> 17 : : # include <linux/notifier.h> 18 : : 19 : : struct clock_event_device; 20 : : struct module; 21 : : 22 : : /* 23 : : * Possible states of a clock event device. 24 : : * 25 : : * DETACHED: Device is not used by clockevents core. Initial state or can be 26 : : * reached from SHUTDOWN. 27 : : * SHUTDOWN: Device is powered-off. Can be reached from PERIODIC or ONESHOT. 28 : : * PERIODIC: Device is programmed to generate events periodically. Can be 29 : : * reached from DETACHED or SHUTDOWN. 30 : : * ONESHOT: Device is programmed to generate event only once. Can be reached 31 : : * from DETACHED or SHUTDOWN. 32 : : * ONESHOT_STOPPED: Device was programmed in ONESHOT mode and is temporarily 33 : : * stopped. 34 : : */ 35 : : enum clock_event_state { 36 : : CLOCK_EVT_STATE_DETACHED, 37 : : CLOCK_EVT_STATE_SHUTDOWN, 38 : : CLOCK_EVT_STATE_PERIODIC, 39 : : CLOCK_EVT_STATE_ONESHOT, 40 : : CLOCK_EVT_STATE_ONESHOT_STOPPED, 41 : : }; 42 : : 43 : : /* 44 : : * Clock event features 45 : : */ 46 : : # define CLOCK_EVT_FEAT_PERIODIC 0x000001 47 : : # define CLOCK_EVT_FEAT_ONESHOT 0x000002 48 : : # define CLOCK_EVT_FEAT_KTIME 0x000004 49 : : 50 : : /* 51 : : * x86(64) specific (mis)features: 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 : : * @state_use_accessors:current state of the device, assigned by the core code 82 : : * @features: features 83 : : * @retries: number of forced programming retries 84 : : * @set_state_periodic: switch state to periodic 85 : : * @set_state_oneshot: switch state to oneshot 86 : : * @set_state_oneshot_stopped: switch state to oneshot_stopped 87 : : * @set_state_shutdown: switch state to shutdown 88 : : * @tick_resume: resume clkevt device 89 : : * @broadcast: function to broadcast events 90 : : * @min_delta_ticks: minimum delta value in ticks stored for reconfiguration 91 : : * @max_delta_ticks: maximum delta value in ticks stored for reconfiguration 92 : : * @name: ptr to clock event name 93 : : * @rating: variable to rate clock event devices 94 : : * @irq: IRQ number (only for non CPU local devices) 95 : : * @bound_on: Bound on CPU 96 : : * @cpumask: cpumask to indicate for which CPUs this device works 97 : : * @list: list head for the management code 98 : : * @owner: module reference 99 : : */ 100 : : struct clock_event_device { 101 : : void (*event_handler)(struct clock_event_device *); 102 : : int (*set_next_event)(unsigned long evt, struct clock_event_device *); 103 : : int (*set_next_ktime)(ktime_t expires, struct clock_event_device *); 104 : : ktime_t next_event; 105 : : u64 max_delta_ns; 106 : : u64 min_delta_ns; 107 : : u32 mult; 108 : : u32 shift; 109 : : enum clock_event_state state_use_accessors; 110 : : unsigned int features; 111 : : unsigned long retries; 112 : : 113 : : int (*set_state_periodic)(struct clock_event_device *); 114 : : int (*set_state_oneshot)(struct clock_event_device *); 115 : : int (*set_state_oneshot_stopped)(struct clock_event_device *); 116 : : int (*set_state_shutdown)(struct clock_event_device *); 117 : : int (*tick_resume)(struct clock_event_device *); 118 : : 119 : : void (*broadcast)(const struct cpumask *mask); 120 : : void (*suspend)(struct clock_event_device *); 121 : : void (*resume)(struct clock_event_device *); 122 : : unsigned long min_delta_ticks; 123 : : unsigned long max_delta_ticks; 124 : : 125 : : const char *name; 126 : : int rating; 127 : : int irq; 128 : : int bound_on; 129 : : const struct cpumask *cpumask; 130 : : struct list_head list; 131 : : struct module *owner; 132 : : } ____cacheline_aligned; 133 : : 134 : : /* Helpers to verify state of a clockevent device */ 135 : 9 : static inline bool clockevent_state_detached(struct clock_event_device *dev) 136 : : { 137 [ - - - - : 9 : return dev->state_use_accessors == CLOCK_EVT_STATE_DETACHED; - - - - - + - - - - ] 138 : : } 139 : : 140 : 6634 : static inline bool clockevent_state_shutdown(struct clock_event_device *dev) 141 : : { 142 [ + - + - ]: 6634 : return dev->state_use_accessors == CLOCK_EVT_STATE_SHUTDOWN; 143 : : } 144 : : 145 : 3 : static inline bool clockevent_state_periodic(struct clock_event_device *dev) 146 : : { 147 [ # # ]: 3 : return dev->state_use_accessors == CLOCK_EVT_STATE_PERIODIC; 148 : : } 149 : : 150 : 7460 : static inline bool clockevent_state_oneshot(struct clock_event_device *dev) 151 : : { 152 [ - + - + : 7460 : return dev->state_use_accessors == CLOCK_EVT_STATE_ONESHOT; + + - + ] 153 : : } 154 : : 155 : 6629 : static inline bool clockevent_state_oneshot_stopped(struct clock_event_device *dev) 156 : : { 157 [ + + ]: 6629 : return dev->state_use_accessors == CLOCK_EVT_STATE_ONESHOT_STOPPED; 158 : : } 159 : : 160 : : /* 161 : : * Calculate a multiplication factor for scaled math, which is used to convert 162 : : * nanoseconds based values to clock ticks: 163 : : * 164 : : * clock_ticks = (nanoseconds * factor) >> shift. 165 : : * 166 : : * div_sc is the rearranged equation to calculate a factor from a given clock 167 : : * ticks / nanoseconds ratio: 168 : : * 169 : : * factor = (clock_ticks << shift) / nanoseconds 170 : : */ 171 : : static inline unsigned long 172 : 3 : div_sc(unsigned long ticks, unsigned long nsec, int shift) 173 : : { 174 : 3 : u64 tmp = ((u64)ticks) << shift; 175 : : 176 : 3 : do_div(tmp, nsec); 177 : : 178 : 3 : return (unsigned long) tmp; 179 : : } 180 : : 181 : : /* Clock event layer functions */ 182 : : extern u64 clockevent_delta2ns(unsigned long latch, struct clock_event_device *evt); 183 : : extern void clockevents_register_device(struct clock_event_device *dev); 184 : : extern int clockevents_unbind_device(struct clock_event_device *ced, int cpu); 185 : : 186 : : extern void clockevents_config_and_register(struct clock_event_device *dev, 187 : : u32 freq, unsigned long min_delta, 188 : : unsigned long max_delta); 189 : : 190 : : extern int clockevents_update_freq(struct clock_event_device *ce, u32 freq); 191 : : 192 : : static inline void 193 : 3 : clockevents_calc_mult_shift(struct clock_event_device *ce, u32 freq, u32 maxsec) 194 : : { 195 : 3 : return clocks_calc_mult_shift(&ce->mult, &ce->shift, NSEC_PER_SEC, freq, maxsec); 196 : : } 197 : : 198 : : extern void clockevents_suspend(void); 199 : : extern void clockevents_resume(void); 200 : : 201 : : # ifdef CONFIG_GENERIC_CLOCKEVENTS_BROADCAST 202 : : # ifdef CONFIG_ARCH_HAS_TICK_BROADCAST 203 : : extern void tick_broadcast(const struct cpumask *mask); 204 : : # else 205 : : # define tick_broadcast NULL 206 : : # endif 207 : : extern int tick_receive_broadcast(void); 208 : : # endif 209 : : 210 : : # if defined(CONFIG_GENERIC_CLOCKEVENTS_BROADCAST) && defined(CONFIG_TICK_ONESHOT) 211 : : extern void tick_setup_hrtimer_broadcast(void); 212 : : extern int tick_check_broadcast_expired(void); 213 : : # else 214 : : static inline int tick_check_broadcast_expired(void) { return 0; } 215 : : static inline void tick_setup_hrtimer_broadcast(void) { } 216 : : # endif 217 : : 218 : : #else /* !CONFIG_GENERIC_CLOCKEVENTS: */ 219 : : 220 : : static inline void clockevents_suspend(void) { } 221 : : static inline void clockevents_resume(void) { } 222 : : static inline int tick_check_broadcast_expired(void) { return 0; } 223 : : static inline void tick_setup_hrtimer_broadcast(void) { } 224 : : 225 : : #endif /* !CONFIG_GENERIC_CLOCKEVENTS */ 226 : : 227 : : #endif /* _LINUX_CLOCKCHIPS_H */