We are observing Data Flash corruption when a Fls_Erase() operation is interrupted due to a power abort/reset condition. After the system restarts, the affected Data Flash region appears corrupted.
During a subsequent attempt to recover the sector using Fls_Erase(), ECC errors are generated when the Flash driver tries to access the affected address range before performing the erase operation. As a result, the erase operation cannot proceed successfully.
We would like to understand the expected behavior of the Flash controller in this scenario and request guidance on the following points:
- Is Data Flash corruption expected if power is lost during an ongoing Fls_Erase() operation?
- Are ECC errors expected when accessing a partially erased/corrupted Flash sector after such an interruption?
- Is there any mechanism or register available to temporarily disable Flash ECC checking so that the corrupted Flash sector can be erased and recovered?
- What is the recommended recovery procedure for handling Data Flash sectors that contain uncorrectable ECC errors following a power interruption?
Target Device: [MPC5746C]
Software Stack: [AUTOSAR / Bare Metal]
Hello,
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Is Data Flash corruption expected if power is lost during an ongoing Fls_Erase() operation?
Yes, that is correct behavior. As data in flash will not match ECC syndromes in flash due to power loss during programming / erase process.
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Are ECC errors expected when accessing a partially erased/corrupted Flash sector after such an interruption?
Yes.
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Is there any mechanism or register available to temporarily disable Flash ECC checking so that the corrupted Flash sector can be erased and recovered?
No. It is permanent HW feature.
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What is the recommended recovery procedure for handling Data Flash sectors that contain uncorrectable ECC errors following a power interruption?
You need to initialize (erase) the corrupted flash block in such case. Once done ECC syndrome will match the data in flash and access wont trigger ECC faults.
For flash erase procedure please refer to reference manual:
Best regards,
Peter