jlaitine opened a new pull request, #15713: URL: https://github.com/apache/nuttx/pull/15713
## Summary We recently found out that it is possible to get memory corruption in scratchpad memory area (0x0a000000 ->) by writes to DRAM (0xa0000000). The memory corruption looks as if there is an incorrect cache eviction from cache way, which is not configured as L2 cache, but as scratchpad memory; even if the way is properly locked by the mask register. The corrupted data is always of cache line size (64 bytes) and aligned to cache line boundary. Furthermore, the content of the corrupted area is 0. We concluded that if scratchpad is being used, the cache way 0, which is automatically enabled at boot, needs to be re-configured as part of scratchpad memory. Otherwise there is a possibility of random memory corruption in the scratchpad area due to cache eviction from way 0. By changing the way how cache ways are allocated between L2 cache and scratchpad, the random memory corruption stops happening. ## Impact Impacts only MPFS platform and corrects some random memory corruption issue in l2zerodevice area. Affects only SW, which is using the scratchpad memory area (L2 cache ways used as memory instead of cache). ## Testing Tested on 3 different custom MPFS250T based HW designs with specifically written test SW writing to DRAM area (0xa0000000) and testing memory content in scratchpad area (0x0a000000). Also the upstream targets' configurations (icicle board and aries som) are updated accordingly. -- This is an automated message from the Apache Git Service. To respond to the message, please log on to GitHub and use the URL above to go to the specific comment. To unsubscribe, e-mail: commits-unsubscr...@nuttx.apache.org For queries about this service, please contact Infrastructure at: us...@infra.apache.org
