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Simplify trap table initialization

Original author: sebastian.huber

Currently, the trap table is statically initialized (see start.S). Unexpected traps end up in system error mode. Later during startup most traps are changed to jump to _ISR_Handler(). This is a side-effect of bsp_spurious_initialize(). The used functions for this dynamic initialization are a bit complex and need cache manager directives which involve all online processors. This should be simplified to cover only basic requirements.

  1. The _ISR_Vector_table should be initialized by _CPU_Initialize_vectors() to an new default handler _SPARC_ISR_handler_default() which just invokes _Terminate().

  2. The traps associated with external interrupts (0x11 up to including 0x1f) should be statically initialized in start.S to jump to _ISR_Handler().

  3. Standard synchronous exceptions such as

  • 0x01 instruction access exception
  • 0x02 illegal instruction
  • 0x03 privileged instruction
  • 0x04 fp disabled
  • 0x07 memory address not aligned
  • 0x08 fp exception
  • 0x09 data access exception
  • 0x0A tag overflow
  • 0x24 cp_disabled
  • 0x28 cp_exception

should also be statically initialize to jump to _ISR_Handler() to invoke the fatal error handler.

If software needs to change the default initialization, then it can use set_vector() or alternatives on demand.

Edited by Amar Takhar