fc-shell TCH DL handler: add support for CSD modes TCH DL capture mechanism in FC Tourmaline firmware has been extended to support CSD modes in addition to speech - add the necessary support on the host tools side. It needs to be noted that this mechanism in its present state does NOT provide the debug utility value that was sought: as we learned only after the code was implemented, TI's DSP has a misfeature in that the buffer we are reading (a_dd_0[]) is zeroed out when the IDS block is enabled, i.e., we are reading all zeros and not the real DL bits we were after. But since the code has already been written, we are keeping it - perhaps we can do some tests with IDS disabled.

#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