Hi ppl,
       Am a newbie to u-boot as well as arm assembly.
wanted to know about the startup code. Below is the
vector table pasted from the code. What i dont
understand is why only the reset vector is PC relative
and all others have memory allocated to hold the
addresses. I mean all other vectors also could be
branch instructions.Any reason ?

.globl _start
_start: b       reset
        ldr     pc, _undefined_instruction
        ldr     pc, _software_interrupt
        ldr     pc, _prefetch_abort
        ldr     pc, _data_abort
        ldr     pc, _not_used
        ldr     pc, _irq
        ldr     pc, _fiq

_undefined_instruction: .word undefined_instruction
_software_interrupt:    .word software_interrupt
_prefetch_abort:        .word prefetch_abort
_data_abort:            .word data_abort
_not_used:              .word not_used
_irq:                   .word irq
_fiq:                   .word fiq

        .balignl 16,0xdeadbeef

Thanks and Regards,
Srinivas Bakki





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