arch/arm64: fix mpu_freeregion #18030
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The limit register contains the enable/disable bit for the MPU region, so it must be written first before writing the base register to ensure proper region disable operation. Signed-off-by: hujun5 <hujun5@xiaomi.com>
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Arch: arm64
xiaoxiang781216
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Jan 20, 2026
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Summary
Fix the RPMSG RTC driver's MPU region free operation by correcting the register write order. The hardware requires writing the limit register first as it contains the enable/disable bit for the region.
Changes Made
mpu_freeregion()to write limit register before base registerImpact
Testing
Tested on ARM64 platform with MPU configuration enabled.
Fixes: None (Bug fix for register sequencing)
Related Issues
None