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////////////////////////////////////////////////////////////////////////////////

//

// Filename:    bootloader.c

//

// Project:     CMod S6 System on a Chip, ZipCPU demonstration project

//

// Purpose:     To copy into RAM, upon boot, sections from the FLASH that

//              need to be placed into RAM.  This also handles setting initial

//              values.

//

// Creator:     Dan Gisselquist, Ph.D.

//              Gisselquist Technology, LLC

//

////////////////////////////////////////////////////////////////////////////////

//

// Copyright (C) 2015-2016, Gisselquist Technology, LLC

//

// This program is free software (firmware): 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 3 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 MERCHANTIBILITY 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.  (It's in the $(ROOT)/doc directory, run make with no

// target there if the PDF file isn't present.)  If not, see

// <http://www.gnu.org/licenses/> for a copy.

//

// License:     GPL, v3, as defined and found on www.gnu.org,

//              http://www.gnu.org/licenses/gpl.html

//

//

////////////////////////////////////////////////////////////////////////////////

//

//

#include "board.h"

// These values will be filled in by the linker.  They are unknown at compile

// time.

extern  int     load_image_start, load_image_end, bss_image_end;

void    bootloader(void) {

        int     len = ((int)&load_image_end) - RAMADDR;

        int     *flash = &load_image_start;

        int     *mem = (int *)RAMADDR;

        for(int i=0; i<len; i++)

                mem[i] = flash[i];

        // While I'd love to continue and clear to the end of memory, doing

        // so will corrupt my stack and perhaps even my return address.  Hence

        // we only do this much.

        for(int i=len; i< ((int)&bss_image_end)-RAMADDR; i++)

                mem[i] = 0;

}