/*
 * 2nd - OMAP "second stage" tt-loader
 *
 * Copyright (C) 2008 Guillaume Bougard <gbougard@pkg.fr>
 * Copyright (C) 2005 Luis Recuerda <lrec@helios.homeip.net>
 *
 * This program is free software; you can redistribute it and/or
 * modify it under the terms of the GNU General Public License
 * as published by the Free Software Foundation; either version 2
 * of the License, or (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA  02111-1307, USA.
 *
 */

#include "config.h"
#include "usb.h"

#define _LSR_   ((volatile u8 *) 0xfffb0014)
#define _THR_   ((volatile u8 *) 0xfffb0000)
#define _RHR_   ((volatile u8 *) 0xfffb0000)

#define MEM_READ_SIZE	32

static char *usb_hdr = "TIS" ;
static char usb_outbuffer[64];

// limited strcpy
static u32 strcpy ( char *dest, char *src )
{
	u32 count = 0 ;
	char *tmp = dest, *s = src;
	
	while ( ++count < 256 && *s != '\0' )
		*tmp++ = *s++ ;
	
	*tmp = '\0' ;
	
	return count ;
}

static u32 memcpy ( char *dest, char *src, u32 count )
{
	char *tmp = dest, *s = src;
	u32 step = count ;

	while (step--)
		*tmp++ = *s++;
	
	return count ;
}

static void bsend (char ch)
{
	while (!((*_LSR_) & 0x20));
	*_THR_= ch;
}

static inline int check_serial (void) { return (*_LSR_) & 0x01; }

static char brecv (void)
{
	while (!((*_LSR_) & 0x01));
	return *_RHR_;
}

char crecv (void)
{
	return brecv ();
}

void csend (char ch)
{
	if (ch == '\n')
		bsend ('\r');
	bsend (ch);
}

void tsend (const char *text)
{
	while (*text)
		csend (*text++);
}

void xsend (unsigned value)
{
	if (value < 10)
		bsend (value + '0');
	else
		bsend (value + ('A'-10));
}

void x8send (u8 value)
{
	xsend (value >> 4);
	xsend (value & 0xf);
}

void x16send (u16 value)
{
	int	i;
	for (i= 0; i < 4; ++i)
	{
		xsend (value >> 12);
		value<<= 4;
	}
}

void x32send (u32 value)
{
	int	i;
	for (i= 0; i < 8; ++i)
	{
		xsend (value >> 28);
		value<<= 4;
	}
}

static void usb_msg (const char cmd, const char *msg)
{
	u32 len = strcpy(usb_outbuffer,usb_hdr);
	usb_outbuffer[len-1] = cmd ;
	
	len += strcpy(&usb_outbuffer[len], msg ? (char *)msg : "" );

	usb_send ( usb_outbuffer, len);
	while (!usb_sent ());
}

static u32 usb_code (char cmd, u32 code)
{
	u32 len = strcpy(usb_outbuffer,usb_hdr);
	usb_outbuffer[len-1] = cmd ;
	(*(u32 *)(usb_outbuffer+len)) = code ;
	len += sizeof(u32);

	usb_send ( usb_outbuffer, len );
	while (!usb_sent ());
	return code ;
}

static void usb_blk (const char cmd, char *mem, u32 size)
{
	u32 len = strcpy(usb_outbuffer,usb_hdr);
	usb_outbuffer[len-1] = cmd ;

	len += memcpy(usb_outbuffer+len,mem,size);
	
	usb_send ( usb_outbuffer, len );
	while (!usb_sent ());
}

// Code from linux-2.6.24.3/arch/arm/mach-omap1/id.c source
static u16 omap_get_jtag_id(void)
{
	u32 prod_id, jtag_id;

	prod_id = omap_readl(OMAP_PRODUCTION_ID_1);
	jtag_id = omap_readl(OMAP32_ID_1);
	
	/* Check for unusable OMAP_PRODUCTION_ID_1 on 1611B/5912 and 730 */
	if (((prod_id >> 20) == 0) || (prod_id == jtag_id))
		prod_id = 0;
	else
		prod_id &= 0xffff;

	if (prod_id)
		return prod_id;

	/* Use OMAP32_ID_1 as fallback */
	prod_id = ((jtag_id >> 12) & 0xffff);

	return prod_id;
}

u32 _main (void)
{	
	u32 address = CFG_LOADADDR ;
	usb_msg ('m', "In omap plateform");
	
	u16 prod_id = omap_get_jtag_id();
	switch (prod_id)
	{
		case 0xb55f:
			usb_msg ('m', "Found supported omap730");
			break;
		default:
			usb_msg ('m', "Unsupported plateform found");
			usb_code ('v', (u32) prod_id);
			break;
	}
	
	// Ready to manage requests
	usb_msg ('r', "Waiting first request");
	
	for (;;)
	{
		u32 total, cmd, index = 0 ;
		
		u8 usb_inbuffer[64];
		usb_recv (usb_inbuffer, sizeof (usb_inbuffer));
		while (!usb_rcvd ());
		
		// Check we are knowing the provided header
		while ( usb_inbuffer[index] == (u8) usb_hdr[index] && usb_hdr[index] != '\0' )
			index++ ;
		
		if ( usb_hdr[index] != '\0' )
			continue ;
		
		cmd = usb_inbuffer[index++] ;
		
		if ((char)cmd == 's') // Ask size to upload
		{
			total= *(u32 *) &usb_inbuffer[index];
			u32 size = 0;

			usb_code ('n', total);

			while (size < total)
			{
				u32	r;
				
				usb_recv ((u8 *)address, sizeof (usb_inbuffer));
				while ((r= usb_rcvd ()) == 0);
								
				address += r ;
				size += r ;
			}
			
			usb_code ('o', size);
			
		} else
		if ((char)cmd == 'f') // load file ACK
		{
			usb_msg ('f', (const char *)&usb_inbuffer[index]);
			
		} else
		if ((char)cmd == 'M') // dump memory command
		{
			usb_blk ('M', (char *)address, MEM_READ_SIZE);
			address += MEM_READ_SIZE ;
			
		} else
		if ((char)cmd == 'a') // set address command
		{
			address = *(u32 *) &usb_inbuffer[index];
			usb_code ('i', address);
			
		} else
		if ((char)cmd == 'c') // call command
		{
			index = ((u32_fnc_t *)address)();
			usb_code ('i', index);
			
		} else
		if ((char)cmd == 'b') // boot command
		{
			usb_code ('b', address );
			// Just return the address where is store the branch to do
			u32 bootaddress = (u32) &address ; // Convert/cast address just to avoid gcc warning
			return bootaddress ;
		}
	}
}