proxmark3/armsrc/start.c

//-----------------------------------------------------------------------------
// Jonathan Westhues, Mar 2006
//
// This code is licensed to you under the terms of the GNU GPL, version 2 or,
// at your option, any later version. See the LICENSE.txt file for the text of
// the license.
//-----------------------------------------------------------------------------
// Just vector to AppMain(). This is in its own file so that I can place it
// with the linker script.
//-----------------------------------------------------------------------------

#ifndef __START_H
#define __START_H

#include "proxmark3_arm.h"
#include "appmain.h"
#include "zlib.h"
#include "BigBuf.h"

static uint8_t *next_free_memory;
extern struct common_area common_area;
extern char __data_src_start__, __data_start__, __data_end__, __bss_start__, __bss_end__;

static voidpf inflate_malloc(voidpf opaque, uInt items, uInt size) {
    uint8_t *allocated_memory;

    allocated_memory = next_free_memory;
    next_free_memory += items * size;
    return allocated_memory;
}

static void inflate_free(voidpf opaque, voidpf address) {
    // nothing to do
}

static void uncompress_data_section(void) {
    z_stream data_section;

    next_free_memory = BigBuf_get_addr();

    // initialize zstream structure
    data_section.next_in = (uint8_t *) &__data_src_start__;
    data_section.avail_in = &__data_end__ - &__data_start__;  // uncompressed size. Wrong but doesn't matter.
    data_section.next_out = (uint8_t *) &__data_start__;
    data_section.avail_out = &__data_end__ - &__data_start__;  // uncompressed size. Correct.
    data_section.zalloc = &inflate_malloc;
    data_section.zfree = &inflate_free;
    data_section.opaque = NULL;

    // initialize zlib for inflate
    int res = inflateInit2(&data_section, 15);
    if (res < 0)
        return;

    // uncompress data segment to RAM
    inflate(&data_section, Z_FINISH);

    // save the size of the compressed data section
    common_area.arg1 = data_section.total_in;
}

void __attribute__((section(".startos"))) Vector(void) {
    /* Stack should have been set up by the bootloader */
    // char *src;
    char *dst, *end;

    uncompress_data_section();

    /* Set up (that is: clear) BSS. */
    dst = &__bss_start__;
    end = &__bss_end__;
    while (dst < end) *dst++ = 0;

    // Set up data segment: Copy from flash to ram
    // src = &__data_src_start__;
    // dst = &__data_start__;
    // end = &__data_end__;
    // while(dst < end) *dst++ = *src++;

    AppMain();
}
#endif