/* * vivi/deriver/serialxmodem.c: *     - an implementation of the xmodem protocol from the spec. * * Based on bootldr/xmodem.c (C) 2000 Compaq Computer Coporation. * * Copyright (C) 2001 MIZI Research, Inc. * * * 1999-01-xx: Edwin Foo <efoo@crl.dec.com> *    - Initial code * * 2001-10-04: Janghoon Lyu <nandy@mizi.com> *    - Modified a little bit. * * 2002-07-04: Janghoon Lyu <nandy@mizi.com> */#include "config.h"#include "machine.h"#include "serial.h"#include "priv_data.h"#include <types.h>/* XMODEM parameters */#define BLOCK_SIZE	128	/* size of transmit blocks */#define RETRIES		20	/* maximum number of RETRIES *//* Line control codes */#define SOH		0x01	/* start of header */#define ACK		0x06	/* Acknowledge */#define NAK		0x15	/* Negative acknowledge */#define CAN		0x18	/* Cancel */#define EOT		0x04	/* end of text */#define GET_BYTE_TIMEOUT 10000000/* global error variable */char *xmodem_errtxt = NULL;int get_byte_err = 0;__u8 volatile rbuffer[BLOCK_SIZE];/* prototypes of helper functions */int get_record(void);__u8 get_byte(void);enum{	SAC_SEND_NAK = 0,	SAC_SENT_NAK = 1,	SAC_PAST_START_NAK = 2};static volatile int seen_a_char = SAC_SEND_NAK;static int one_nak = 0;static unsigned long xmodem_timeout = GET_BYTE_TIMEOUT;char debugbuf[4096];int db_idx = 0;void bufputs(char *s){	size_t len = strlen(s) + 1;	if (len + db_idx > sizeof(debugbuf))		len = sizeof(debugbuf) - db_idx;	if (len) {		memcpy(&debugbuf[db_idx], s, len);		db_idx += len;	}}void reset_debugbuf(void){	memset(debugbuf, 0x2a, sizeof(debugbuf));	db_idx = 0;}__u32 xmodem_receive(char *dldaddr, size_t len){	char ochr;	int r = 0, rx_block_num = 0, error_count = 0;	__u32 foffset = 0;	int i;	int ret;	xmodem_errtxt = NULL;	seen_a_char = 0;	one_nak = get_param_value("xmodem_one_nak", &ret);	if (ret) one_nak = 0;	xmodem_timeout = get_param_value("xmodem_initial_timeout", &ret);	if (ret) xmodem_timeout = GET_BYTE_TIMEOUT;	rx_block_num = 1;	error_count = RETRIES;	do {		if ((r = get_record()) == (rx_block_num & 255)) {			error_count = RETRIES;			for (i = 0; i <BLOCK_SIZE; i++)				*(__u8 *)(dldaddr+foffset+i) = rbuffer[i];			xmodem_errtxt = "RX PACKET";			rx_block_num++;			ochr = ACK;			foffset += BLOCK_SIZE;		} else {			switch (r) {			case -1: /* TIMEOUT */				xmodem_errtxt = "TIMEOUT";				ochr = NAK;				break;			case -2: /* Bad block */				xmodem_errtxt = "BAD BLOCK#";				/* eat teh rest of the block */				get_byte_err = 0;				while (get_byte_err != -1) get_byte();				ochr = NAK;				break;			case -3: /* Bad checksum */				xmodem_errtxt = "BAD CHKSUM";				ochr = NAK;				break;			case -4: /* End of file */				xmodem_errtxt = "DONE";				ochr = ACK;				break;			case -5: /* Cancel */				xmodem_errtxt = "ABORTED";				ochr = ACK;				break;			default: /* Block out of sequence */				xmodem_errtxt = "WRONG BLK";				ochr = NAK;			}			error_count--;		}		putc(ochr);	} while ((r > -3) && error_count);	if ((!error_count) || (r != -4)) {		foffset = 0;	/* indicate failure to caller */		/*printk("x-modem error: %s\n", xmodem_errtxt); */	}	return foffset;}/* * Read a record in the XMODEM protocol, return the block number * (0-255) if successful, or one of the following return codes: * 	-1 = Bad byte * 	-2 = Bad block number * 	-3 = Bad block checksum * 	-4 = End of file * 	-5 = Canceled by remote */int get_record(void){	int c, block_num = 0;	int i;	__u32 check_sum;	/* clear the buffer */	for (i = 0; i < BLOCK_SIZE; i++)		rbuffer[i] = 0x00;	check_sum = 0;	i = -2;	c = get_byte();	if (get_byte_err)		return -1;	switch (c) {	case SOH:	/* Receive packet */		for (;;) {			c = get_byte();			if (get_byte_err)				return -1;			switch (i) {			case -2: 				block_num = c;				break;			case -1:#if 0#ifdef CHECK_NEGATED_SECTNUM				if (c != (-block_num -1))					return -2;#endif#endif				break;			case BLOCK_SIZE:				if ((check_sum & 0xff) != c)					return -3;				else					return block_num;				break;			default:				rbuffer[i] = c;				check_sum += c;			}			i++;		}	case EOT:	/* end of file encountered */		return -4;	case CAN:	/* cancel protocol */		return -5;	default:		return -5;	}}/* get_byte should use one of the timer's for a CPU clock independent timeout */__u8 get_byte(){	int c, ret;again:	c = 0;	get_byte_err = 0; /* reset errno */	c = awaitkey(xmodem_timeout, &get_byte_err);	if (get_byte_err) {		if (seen_a_char == SAC_SEND_NAK || !one_nak) {			bufputs("timeout nak");			putc(NAK);	/* make the sender go */		}		if (seen_a_char < SAC_PAST_START_NAK) {			bufputs("goto again");			seen_a_char = SAC_SENT_NAK;			xmodem_timeout = get_param_value("xmodem_timeout", &ret);			if (ret) xmodem_timeout = GET_BYTE_TIMEOUT;			goto again;		}	}	if (get_byte_err == 0)		seen_a_char = SAC_PAST_START_NAK;	return (c);}