u-boot/post/board/pdm360ng/coproc_com.c

/*
 * (C) Copyright 2010 DENX Software Engineering,
 * Anatolij Gustschin, agust@denx.de.
 *
 * SPDX-License-Identifier:	GPL-2.0+
 */

/*
 * Co-Processor communication POST
 */
#include <common.h>
#include <post.h>
#include <serial.h>

/*
 * Actually the termination sequence of the coprocessor
 * commands is "\r\n" (CR LF), but here we use a side effect of
 * the putc() routine of the serial driver which checks for LF
 * and sends CR before sending LF. Therefore the termination
 * sequence in the command below is only "\n".
 * "alive" string is the coprocessor response for ping command
 * and not a command, therefore it is terminated with "\r\n".
 */
char alive[] = "$AL;38\r\n";
char ping[] = "$PI;2C\n";

int coprocessor_post_test(int flags)
{
	struct stdio_dev *cop_port;
	int ret;
	char buf[10];

	/* Test IO Coprocessor communication */
	cop_port = open_port(4, CONFIG_SYS_PDM360NG_COPROC_BAUDRATE);
	if (!cop_port)
		return -1;

	write_port(cop_port, ping);
	udelay(CONFIG_SYS_PDM360NG_COPROC_READ_DELAY);

	memset(buf, 0, sizeof(buf));
	ret = read_port(cop_port, buf, sizeof(buf));
	close_port(4);
	if (ret <= 0) {
		post_log("Error: Can't read IO Coprocessor port.\n");
		return -1;
	}

	if (strcmp(buf, alive)) {
		post_log("Error: IO-Cop. resp.: %s\n", buf);
		return -1;
	}

	/* Test WD Coprocessor communication */
	cop_port = open_port(1, CONFIG_SYS_PDM360NG_COPROC_BAUDRATE);
	if (!cop_port) {
		post_log("Error: Can't open WD Coprocessor port.\n");
		return -1;
	}

	write_port(cop_port, ping);
	udelay(CONFIG_SYS_PDM360NG_COPROC_READ_DELAY);

	memset(buf, 0, sizeof(buf));
	ret = read_port(cop_port, buf, sizeof(buf));
	close_port(1);
	if (ret <= 0) {
		post_log("Error: Can't read WD Coprocessor port.\n");
		return -1;
	}

	if (strcmp(buf, alive)) {
		post_log("Error: WD-Cop. resp.: %s\n", buf);
		return -1;
	}

	return 0;
}