nuttx/arch
Felipe Moura 89b8c5fc7f espressif: stop double-counting light sleep in the system clock
esp_pmstandby() fed up_step_idletime() the sleep duration it *asked* for
(time_in_us) rather than the one it actually got (rtc_diff_us), and did so
unconditionally.  Both halves are wrong.

esp_pm_light_sleep_start() already stalls and restores the systimer
itself, but only where SOC_SLEEP_SYSTIMER_STALL_WORKAROUND is defined --
esp32c3 and esp32p4.  On every other SoC, esp32s3 included, the systimer
keeps counting straight through light sleep, so the time is already in
the clock and stepping it again adds it twice.

Measured on an esp32s3-xiao: over 54 min with 1919 light sleeps totalling
454.7 s, the monotonic clock ran 443.2 s fast -- 0.97 of the time slept,
i.e. counted exactly twice, leaving the clock 13.8% fast.  Anything that
reconstructs wall time from CLOCK_MONOTONIC inherits that error; for this
collar it corrupted every IMU sample timestamp.

Invisible until light sleep started happening for real, because a board
that never sleeps never steps the clock.

Note for upstream: the risc-v copy here only switches to the measured
duration and does not gate on SOC_SLEEP_SYSTIMER_STALL_WORKAROUND.  The
two should be reconciled before this is proposed -- it is kept as-is so
the asymmetry is visible rather than silently decided.

Signed-off-by: Felipe Moura <moura.fmo@gmail.com>
Assisted-by: Claude:claude-opus-5
2026-09-22 19:30:21 +08:00
..
arm arch/arm/stm32h5: add missing I2C2/I2C4 pin remap options 2026-09-22 13:32:10 +08:00
arm64 arch/arm64: AES using the Armv8 Cryptography Extension. 2026-09-21 18:43:36 +08:00
avr arch, boards, cmake: Build C++ ELF modules without __cxa_atexit. 2026-09-04 15:44:24 -03:00
ceva arch/atomic: remove up_testset in spinlock 2026-09-08 08:58:54 +08:00
dummy
hc tools: fix stale archive members surviving a Kconfig-driven CSRCS change 2026-07-28 21:26:03 -03:00
mips arch, boards, cmake: Build C++ ELF modules without __cxa_atexit. 2026-09-04 15:44:24 -03:00
misoc arch, boards, cmake: Build C++ ELF modules without __cxa_atexit. 2026-09-04 15:44:24 -03:00
or1k arch, boards, cmake: Build C++ ELF modules without __cxa_atexit. 2026-09-04 15:44:24 -03:00
renesas nuttx/libc: refine the atomic related Kconfig 2026-08-24 13:20:45 +08:00
risc-v espressif: stop double-counting light sleep in the system clock 2026-09-22 19:30:21 +08:00
sim sched/pthread: Implement pthread_sigqueue 2026-09-21 14:53:26 +08:00
sparc arch/atomic: remove up_testset in spinlock 2026-09-08 08:58:54 +08:00
tricore arch/atomic: remove up_testset in spinlock 2026-09-08 08:58:54 +08:00
x86 arch/x86: Add -P to CPP to suppress linemarkers. 2026-09-17 16:21:59 +08:00
x86_64 arch/intel64: don't touch the outgoing stack after releasing the csection 2026-09-15 11:39:05 -03:00
xtensa espressif: stop double-counting light sleep in the system clock 2026-09-22 19:30:21 +08:00
z16 tools: fix stale archive members surviving a Kconfig-driven CSRCS change 2026-07-28 21:26:03 -03:00
z80
CMakeLists.txt cmake: Use NUTTX(_DIR/_BIN_DIR) instead CMAKE(_SRC_DIR/_BIN_DIR) 2026-08-09 11:13:08 -03:00
Kconfig binfmt, arch/arm: Add the CONFIG_FDPIC option and the ABI header. 2026-09-08 16:31:16 -03:00