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.section ".text.kernel"
.globl kernel_main
kernel_main:
bl sysinit
///https://wiki.osdev.org/ARM_Paging
// Query the ID_MMFR0 register
mrc p15, 0, r0, c0, c1, 4
bl uart_hexn
// Switch to user mode
cps #0x10
// Intentional undefined instruction
//.word 0xf7f0a000
// This will fail in user mode
mrc p15, 3, r0, c15, c0, 0
// Supervisor Call #1 - Does nothing special
svc #1
mrs r0, cpsr
bl uart_hexn
// Supervisor Call #1 - Returns in supervisor mode
svc #0
mrs r0, cpsr
bl uart_hexn
1:
wfe
b 1b
.section ".data"
.globl cntfrq
cntfrq: // 32 bits
.word 0
.globl cmdidx
cmdidx:
.word 0
.globl cmd
cmd:
.space 2049
.section ".bss.heap"
mheap:
.space 0x100000
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