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// armv7 mode
 
// Entry point for the kernel.
// r15 -> should begin execution at 0x8000.
// r0 -> 0x00000000
// r1 -> 0x00000C42
// r2 -> 0x00000100 - start of ATAGS
// preserve these registers as argument for kernel_main
	
.global _boot // make entry point label global
_boot:
        // Only let the first core execute
        mrc p15, 0, r3, c0, c0, 5
        and r3, r3, #3
        cmp r3, #0
        beq proceed
	// this is a kind of blef - races can theoretically still occur
	// when the main core overwrites this part of memory
	wfe

proceed:
        // Initialize the stack (_stack_top is defined in linker.ld)
        ldr sp, =_stack_top
 
        // Call kernel_main
        ldr r3, =kernel_main
        bx r3