Bus errors from userspace on ARCompact based cores are handled by core
as a high priority L2 interrupt but current code treated it as interrupt
Handling an interrupt like exception is certainly not going to go unnoticed.
(and it worked so far as we never saw a Bus error from userspace until
IPPK guys tested a DDR controller with ECC error detection etc hence
needed to explicitly trigger/handle such errors)
- So move mem_service exception handler from common code into ARCv2 code.
- In ARCompact code, define mem_service as L2 interrupt handler which
just drops down to pure kernel mode and goes of to enqueue SIGBUS
Reported-by: Nelson Pereira <npereira@synopsys.com>
Tested-by: Ana Martins <amartins@synopsys.com>
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
For Run-on-reset, non masters need to spin wait. For Halt-on-reset they
can jump to entry point directly.
Also while at it, made reset vector handler as "the" entry point for
kernel including host debugger based boot (which uses the ELF header
entry point)
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
This is done by improving the laddering logic !
Before:
if Exception
goto excep_or_pure_k_ret
if !Interrupt(L2)
goto l1_chk
else
INTERRUPT_EPILOGUE 2
l1_chk:
if !Interrupt(L1) (i.e. pure kernel mode)
goto excep_or_pure_k_ret
else
INTERRUPT_EPILOGUE 1
excep_or_pure_k_ret:
EXCEPTION_EPILOGUE
Now:
if !Interrupt(L1 or L2) (i.e. exception or pure kernel mode)
goto excep_or_pure_k_ret
; guaranteed to be an interrupt
if !Interrupt(L2)
goto l1_ret
else
INTERRUPT_EPILOGUE 2
; by virtue of above, no need to chk for L1 active
l1_ret:
INTERRUPT_EPILOGUE 1
excep_or_pure_k_ret:
EXCEPTION_EPILOGUE
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
Returning from pure kernel mode and exception mode use the same code
anyways. Remove one the duplicate blocks
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>