• Correct usage of the NSTable bit in aarch64/armv7a LPAE
    I'm porting our armv7a-short descriptor OS to LPAE and aarch64. In the short descriptor MMU, the "NS" bit can only be found in the first level of the MMU (I'll call it the SECTION level), meaning that...
  • translational table : block and table descriptor
    Hello Experts, I am trying to understand in the attached snapshot, how the values of m and n are derived for table and block descriptors respectively ? Can anyone please explain me since I am...
  • armv7a/armv8 : Undefined Abort Exception and MMU
    Hi ! When MMU is enabled, and a undefined abort exception is triggered, are we sure that the address stored in the `lr` / `elr_elx` registers is actually mapped by the MMU, or should I check that before...
  • XN bit in translation descriptor
    Hi all, I am studying ARMv8_VSMA. I have a question about the XN bit in the table descriptor. In the manual, there is an explanation about this as below. Execute-never controls determine whether instructions...