Make the ISA extension init code paths optional in crt0.S
Having the ability to disable these extension-specific code paths is
necessary for low-level hardware development and unit testing.
This CL also removes irq_vector.S as it 1) was resulting in undefined
symbol errors when disabling exceptions, 2) wasn't actually being
actively used by crt0.S (rather than pointing the mtvec CSR to the
indirect jump table in irq_vector.S, crt0.S was setting it directly to
the exception handler in crt0.S; irq_vector.S was in effect only used
for resets and the jump table defined was never used at all), and 3)
isn't plan of record to support interrupts on Springbok anyway.
Change-Id: Idfb5cc45b76db1f664b1d953f4a7c2c8a5f1d174
5 files changed
