Jukka Laitinen 429252152a arch/arm64/src/common/arm64_arch_timer.c: Remove clock drift from tick timer ... This fixes two issues with the tick timer 1) Each tick was longer than the requested period. This is because setting the compare register was done by first reading the current time, and only after that setting the compare register. In addition, when handling the timer interrupts in arch_alarm.c / oneshot_callback, the current_tick is first read, all the tick handling is done and only after that the next tick is started. The whole tick processing time was added to the total tick time. 2) When the compare time is not aligned with tick period, and is drifting, eventually any call to ONESHOT_TICK_CURRENT would either return the current tick, or the next one, depending on the rounding of division by the cycle_per_tick. This again leads to oneshot_callback randomly handling two ticks at a time, which breaks all wdog based timers, causing them to randomly timeout too early. The issues are fixed as follows: Align the compare time register to be evenly divisible by cycle_per_tick. This will lead arm64_tick_current always to return the currently ongoing tick, fixing 2). Also calculating the next tick's start from the aligned current count will fix 1), as there is no time drift in the start cycle. Signed-off-by: Jukka Laitinen <jukkax@ssrc.tii.ae>		2024-09-30 19:23:01 +08:00
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include	arch: inline up_switch_context,in arm arm64	2024-09-28 19:08:15 +08:00
src	arch/arm64/src/common/arm64_arch_timer.c: Remove clock drift from tick timer	2024-09-30 19:23:01 +08:00
CMakeLists.txt	CMake:init arm64 CMake qemu-armv8a build	2023-12-27 07:27:17 -08:00
Kconfig	arm64:add busy wait flag	2024-09-29 00:01:44 +08:00