.section .text
.align 2
.global delay
.include "memory_map.inc"


# a0 is delay in milliseconds argument

delay:
	addi sp, sp, -16 # Allocate stack frame
	sw ra, 12(sp)    # save return address to the stack

	li t0, MTIME     # load the timer register
	lw t1, 0(t0)     # load value of the timer

	li t2, MTIME_FREQUENCY # get clock freq (approx.)
	mul t2, t2, a0         # multiply milliseconds with freq
	add t2, t1, t2         # target mtime is now in t2

1:
	lw t1, 0(t0)      # load value of the timer
	blt t1, t2, 1b    # keep looping until target mtime has been reached

	lw ra, 12(sp)   # load return address
	addi sp, sp, 16 # deallocate stack frame
	ret