Kindly refer to the documents which portrays exactly the difference between the Arm architecture Armv7 to Armv8.
At least the overview of the changes in terms of advantages and disadvantages
A general point, Armv8-A has two execution states AArch32 and AArch64. Where AArch32 provides backwards compatibility with Armv7-A.
For something like porting it makes a lot of difference whether you mean Armv8-A AArch64 or Armv8-A AArch32.
If my SOC runs the startup code in AArch32 mode, can I use the ARMv7-A startup for ArmV8-A aarch32 mode?
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