view target-utils/loadagent/serextra.S @ 755:28d58a8cd704

fc-fsio help: write-battery-table change documented
author Mychaela Falconia <falcon@freecalypso.org>
date Thu, 05 Nov 2020 23:17:31 +0000
parents 3229940734e5
children
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#include "ns16550.h"

@ extra serial I/O functions for loadagent binary operations

	.text
	.code	32
	.globl	serial_out_if_empty
serial_out_if_empty:
	ldr	r1, =uart_base
	ldr	r2, [r1]
	ldrb	r3, [r2, #NS16550_LSR]
	tst	r3, #NS16550_LSR_THRE
	strneb	r0, [r2, #NS16550_THR]
	bx	lr