doc/Host-tools-overview: tiffs-mkfs description updated The first version of tiffs-mkfs did not include a journal file in the created FFS, expecting the firmware to create it on first boot. All historical firmwares prior to a recent FC fix (2020-05) contain a bug in that code path, thus images made with the first version of tiffs-mkfs were only acceptable to very recent FC firmwares. tiffs-mkfs has now been extended to include an empty journal in the created FFS, thus the restriction of working with recent fw only has been lifted.

#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