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#include <fbos/mm.h>
.global _start
.section .head.text
_start:
// Mask all interrupts
csrw sie, zero
csrw sip, zero
// Flush the instruction cache
fence.i
// Reset all registers except ra, a0, a1.
li sp, 0
li gp, 0
li tp, 0
li t0, 0
li t1, 0
li t2, 0
li s0, 0
li s1, 0
li a2, 0
li a3, 0
li a4, 0
li a5, 0
li a6, 0
li a7, 0
li s2, 0
li s3, 0
li s4, 0
li s5, 0
li s6, 0
li s7, 0
li s8, 0
li s9, 0
li s10, 0
li s11, 0
li t3, 0
li t4, 0
li t5, 0
li t6, 0
csrw sscratch, 0
// Point tp and sp to the init task.
la tp, tasks
la sp, tasks + THREAD_SIZE
// The `start_kernel` function requires an argument to be passed, which is
// the pointer to the `fdt` blob. The bootloader puts this on the `a1`
// register, so let's move it now to `a0`.
mv a0, a1
// Start the kernel.
tail start_kernel
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