[U-Boot-Users] question regarding startup code

[srinivas bakki]

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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