| /*- |
| * ---------------------------------------------------------------------------- |
| * "THE BEER-WARE LICENSE" (Revision 42): |
| * <phk@FreeBSD.ORG> wrote this file. As long as you retain this notice you |
| * can do whatever you want with this stuff. If we meet some day, and you think |
| * this stuff is worth it, you can buy me a beer in return. Poul-Henning Kamp |
| * ---------------------------------------------------------------------------- |
| * |
| * $FreeBSD$ |
| */ |
| |
| #ifndef _BSD_SYS_TIMETC_H_ |
| #define _BSD_SYS_TIMETC_H_ |
| |
| #ifndef _FREEBSD_KERNEL |
| #error "no user-serviceable parts inside" |
| #endif |
| |
| /*- |
| * `struct timecounter' is the interface between the hardware which implements |
| * a timecounter and the MI code which uses this to keep track of time. |
| * |
| * A timecounter is a binary counter which has two properties: |
| * * it runs at a fixed, known frequency. |
| * * it has sufficient bits to not roll over in less than approximately |
| * max(2 msec, 2/HZ seconds). (The value 2 here is really 1 + delta, |
| * for some indeterminate value of delta.) |
| */ |
| |
| struct timecounter; |
| typedef u_int timecounter_get_t(struct timecounter *); |
| typedef void timecounter_pps_t(struct timecounter *); |
| |
| struct timecounter { |
| timecounter_get_t *tc_get_timecount; |
| /* |
| * This function reads the counter. It is not required to |
| * mask any unimplemented bits out, as long as they are |
| * constant. |
| */ |
| timecounter_pps_t *tc_poll_pps; |
| /* |
| * This function is optional. It will be called whenever the |
| * timecounter is rewound, and is intended to check for PPS |
| * events. Normal hardware does not need it but timecounters |
| * which latch PPS in hardware (like sys/pci/xrpu.c) do. |
| */ |
| u_int tc_counter_mask; |
| /* This mask should mask off any unimplemented bits. */ |
| u_int64_t tc_frequency; |
| /* Frequency of the counter in Hz. */ |
| char *tc_name; |
| /* Name of the timecounter. */ |
| int tc_quality; |
| /* |
| * Used to determine if this timecounter is better than |
| * another timecounter higher means better. Negative |
| * means "only use at explicit request". |
| */ |
| |
| void *tc_priv; |
| /* Pointer to the timecounter's private parts. */ |
| struct timecounter *tc_next; |
| /* Pointer to the next timecounter. */ |
| }; |
| |
| extern struct timecounter *timecounter; |
| |
| u_int64_t tc_getfrequency(void); |
| void tc_init(struct timecounter *tc); |
| void tc_setclock(struct timespec *ts); |
| void tc_ticktock(void); |
| |
| #ifdef SYSCTL_DECL |
| SYSCTL_DECL(_kern_timecounter); |
| #endif |
| |
| #endif /* !_BSD_SYS_TIMETC_H_ */ |