Now that we now that jz4760b implements EBASE, we can use it to rebase
exceptions to use a k1seg address, that maps to the physical address of the
TCSM0. It requires to enable HAB1 to have this translation. This most the most
inefficient way to access tighly coupled memory ever, but it works.
Change-Id: I894ca929c9835696102eb2fef44b06e6eaf96d44
The stub is quite versatile: it can be loaded using bootrom or another other
means (like factory boot on Fiio X1). It relocates itself to TCSM0 and provides
basic functionality (it does not recover from failed read/writes at the moment).
Change-Id: Ib646a4b43fba9358d6f93f0f73a5c2e9bcd775a7