[Backport v3.7-branch] driver: timer: npcx: fix timer accuracy issue #88989
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This commit fixes some potential leakage in the timer driver. Signed-off-by: Jun Lin <[email protected]> (cherry picked from commit bdf0500)
Originally, when the timer's source clock is 32.768 kHz, the timer driver uses two consecutive reads to ensure the timer reading is correct. However, it is not robust enough due to an asynchronous timing issue in the chip. The workaround is to add at least two NOPs between the LDR and CMP instructions. This commit implements the workaround in the assembly code to ensure it is not affected by the compiler toolchain or optimization flags. Signed-off-by: Jun Lin <[email protected]> (cherry picked from commit 2bda7b8)
kartben
approved these changes
Apr 30, 2025
MulinChao
approved these changes
May 7, 2025
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Backport 2bda7b8~2..2bda7b8 from #82905
Fixes #88946