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How memory type is decided when MMU is disabled ?

Xinwei

Hi, 

I got a 'data abort' exception from a LDR instruction LDR w0, [x8].  It's because the address contained in x8 is not 4-byte aligned.  I want to disable the aligment check so I did use '--nounaligment-access' '-mno-unalignement-access' when compiling, and set SCTLR_ELx.A to be 0. But I am not sure if the memory address I am accessing is from a 'Normal' memory or a 'Device' memory because I disabled the MMU in the bootcode. 

Any one has an idea how the memory type is decided when mmu is disabled ? 

Or any other thoughts why the LDR instruction triggers an 'data abort' exception ?

Thanks and best regards,

Xinwei

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