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.global _start
.section .head.text
_start:
// Start by simply disabling interrupts.
csrw sie, zero
csrw sip, zero
fence.i
// Initialize the 'a4' register, which is going to be used for printing out
// the end message by the main hart.
li a4, 0
// Hart lottery! The main hart will win it, the rest will simply jump into
// .Lhalt. See hsm.c for more details.
la a3, hart_lottery
li a2, 1
amoadd.w a3, a2, (a3)
bnez a3, .Lhalt
// Setup a dummy stack and call the kernel.
la sp, _STACK_PTR
call start_kernel
// We actually expect the main kernel routine to quit. Here we make the
// .Lhalt part of the code to print special messages for that case.
addi a4, a4, 1
.Lhalt:
// Increase the number of hart that lost the lottery.
la a3, hart_failed_lottery
li a2, 1
amoadd.w zero, a2, (a3)
// If it's the main hart that is bailing out, first print some final
// messages.
beqz a4, .Lend
call print_lottery
call end
// Die Bart, die!
.Lend:
wfi
j .Lend
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