This patch implements clock_adjtime() with CLOCKFD support, enabling
precise time and frequency adjustments for PTP clocks through the
standard POSIX clock API.
Key changes include:
1. New clock_adjtime() system call:
- Added sched/clock/clock_adjtime.c implementation
- Provides POSIX-compliant time adjustment interface
- Supports both standard clocks and CLOCKFD-based dynamic clocks
- Added CONFIG_CLOCK_ADJTIME Kconfig option
2. CLOCKFD support in clock_adjtime():
- Detects CLOCKFD-encoded clockids via CLOCKFD_TO_FD() check
- Extracts file descriptor and validates through fs_getfilep()
- Issues PTP_CLOCK_ADJTIME ioctl to underlying PTP clock device
- Returns clock status and adjustment results via struct timex
3. Enhanced struct timex support:
- Extended include/sys/timex.h with additional ADJ_* flags
- Added ADJ_OFFSET, ADJ_FREQUENCY, ADJ_MAXERROR, ADJ_ESTERROR
- Added ADJ_STATUS, ADJ_TIMECONST, ADJ_TAI, ADJ_SETOFFSET
- Added ADJ_MICRO, ADJ_NANO for time unit selection
- Added STA_* status flags for clock state reporting
4. Clock operations supported:
- ADJ_SETOFFSET: Apply time offset adjustment
- ADJ_FREQUENCY: Adjust clock frequency (PPM)
- ADJ_MAXERROR: Set maximum error estimate
- ADJ_ESTERROR: Set estimated error
- ADJ_STATUS: Modify clock status bits
- ADJ_NANO: Use nanosecond resolution
- ADJ_SETOFFSET: Set absolute time offset
5. API declarations:
- Added clock_adjtime() prototype in include/nuttx/clock.h
- Enabled by CONFIG_CLOCK_ADJTIME configuration
- Compatible with Linux clock_adjtime() interface
Usage example:
int fd = open("/dev/ptp0", O_RDWR);
struct timex tx = {0};
tx.modes = ADJ_FREQUENCY;
tx.freq = 10000000; /* Adjust frequency by 10 PPM */
clock_adjtime(CLOCKFD(fd), &tx);
close(fd);
This completes the PTP clock framework's POSIX clock API integration,
providing comprehensive time control capabilities for precision timing
applications including PTP synchronization daemons (ptp4l, timemaster).
Signed-off-by: dongjiuzhu1 <dongjiuzhu1@xiaomi.com>
Replace the spinlock/sched_lock pair in the sched clock module with
spin_lock_irqsave_nopreempt() to improve code clarity and consistency.
Signed-off-by: Chengdong Wang wangchengdong@lixiang.com
This commit replaced periodical timer with the wd_start_next to improve the timing accuracy.
Signed-off-by: ouyangxiangzhen <ouyangxiangzhen@xiaomi.com>
The missing <nuttx/spinlock.h> header caused following compile errors:
CC: clock/clock_adjtime.c clock/clock_adjtime.c: In function 'adjtime_wdog_callback':
clock/clock_adjtime.c:67:11: error: implicit declaration of function 'spin_lock_irqsave' [-Wimplicit-function-declaration]
67 | flags = spin_lock_irqsave(&g_adjtime_lock);
| ^~~~~~~~~~~~~~~~~
clock/clock_adjtime.c:78:3: error: implicit declaration of function 'spin_unlock_irqrestore' [-Wimplicit-function-declaration]
78 | spin_unlock_irqrestore(&g_adjtime_lock, flags);
Signed-off-by: Michal Lenc <michallenc@seznam.cz>
Most tools used for compliance and SBOM generation use SPDX identifiers
This change brings us a step closer to an easy SBOM generation.
Signed-off-by: Alin Jerpelea <alin.jerpelea@sony.com>
Previous adjtime() implementation was limited to adjusting system
timer tick period. This commit reimplements the internals to use
a kernel watchdog timer. Platform-independent part of the code now
works also for adjusting hires RTC and tickless timer rate.
User code facing API is unchanged. Architecture code API has changed:
up_adj_timer_period() is replaced by up_adjtime().
Other improvements:
- Support query of remaining adjustment by passing NULL to first
argument of adjtime(). This matches Linux behavior.
- Improve resolution available for architecture driver, previously
limited to 1 microsecond per tick. Now 1 nanosecond per second.
1) Previously adjustments less than 1 microsecond per tick would be
completely ignored. Now they are applied over a shorter period at
a rate of 1 us per tick.
2) Previously CLOCK_ADJTIME_PERIOD was in units of 1/100th of second.
Change to milliseconds to be more generally useful unit.
Change setting name to CLOCK_ADJTIME_PERIOD_MS to make the unit change
easier to notice.
3) Previously CLOCK_ADJTIME_SLEWLIMIT was in percentage.
Most clock crystals have better accuracy than 1%, so the minimum slew
rate was excessive. Change to CLOCK_ADJTIME_SLEWLIMIT_PPM with setting
value in parts per million.
4) No need to use floating point math in clock_adjtime.c.
This commit adds Linux like adjtime() interface that is used to correct
the system time clock if it varies from real value. The adjustment is
done by slight adjustment of clock period and therefore the adjustment
is without time jumps (both forward and backwards)
The implementation is enabled by CONFIG_CLOCK_ADJTIME and separated from
CONFIG_CLOCK_TIMEKEEPING functions. Options CONFIG_CLOCK_ADJTIME_SLEWLIMIT
and CONFIG_CLOCK_ADJTIME_PERIOD can be used to control the adjustment
speed.
Interfaces up_get_timer_period() and up_adj_timer_period() has to be
defined by architecture level support.
This is not a POSIX interface but derives from 4.3BSD, System V.
It is also supported for Linux compatibility.
Signed-off-by: Michal Lenc <michallenc@seznam.cz>
