USB DFU (Device Firmware Upgrade) firmware for Atmel SAM devices supported by ASF4
You can not select more than 25 topics Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.
 
 
osmo-asf4-dfu/usb_dfu_main.c

163 lines
5.3 KiB

/**
* \file
* \brief USB DFU bootloader implementation (DFU mode)
*
* Copyright (c) 2018-2019 sysmocom -s.f.m.c. GmbH, Author: Kevin Redon <kredon@sysmocom.de>
*
* This library is free software; you can redistribute it and/or
* modify it under the terms of the GNU Lesser General Public
* License as published by the Free Software Foundation; either
* version 2.1 of the License, or (at your option) any later version.
*
* This library 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
* Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public
* License along with this library; if not, write to the Free Software
* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
*/
#include <errno.h>
#include "atmel_start.h"
#include "atmel_start_pins.h"
/** Start address of the application in flash
* \remark must be initialized by check_bootloader
*/
static uint32_t* application_start_address;
/** Location of the DFU magic value to force starting DFU */
static volatile uint32_t* dfu_magic = (uint32_t*)HSRAM_ADDR; // magic value should be written at start of RAM
/** Check if the bootloader is valid
* \return true if the bootloader is valid and can be run
* \remark initializes application_start_address
*/
static bool check_bootloader(void)
{
if (hri_nvmctrl_read_STATUS_BOOTPROT_bf(FLASH_0.dev.hw) > 15) { // ensure BOOTPROT setting is valid
return false;
}
application_start_address = (uint32_t*)((15 - hri_nvmctrl_read_STATUS_BOOTPROT_bf(FLASH_0.dev.hw)) * 8192); // calculate bootloader size to know start address of the application (e.g. after the bootloader)
if (0 == application_start_address) { // no space has been reserved for the bootloader
return false;
}
return true;
}
/** Check if starting the bootloader is forced
* \return true of the DFU bootloader should be started
*/
static bool check_force_dfu(void)
{
if (0x44465521 == *dfu_magic) { // check for the magic value which can be set by the main application
*dfu_magic = 0; // erase value so we don't stay in the DFU bootloader upon reset
return true;
}
if (0 == gpio_get_pin_level(BUTTON_FORCE_DFU)) { // signal is low when button is pressed
return true;
}
return false;
}
/** Check if the application is valid
* \return true if the application is valid and can be started
* \warning application_start_address must be initialized
*/
static bool check_application(void)
{
/* the application starts with the vector table
* the first entry in the vector table is the initial stack pointer (SP) address
* the stack will be placed in RAM which begins at 0x2000 0000, and there is up to 256 KB of RAM (0x40000).
* if the SP is not in this range (e.g. flash has been erased) there is no valid application
* the second entry in the vector table is the reset address, corresponding to the application start
*/
return (HSRAM_ADDR == ((*application_start_address) & 0xFFF80000));
}
/** Start the application
* \warning application_start_address must be initialized
*/
static void start_application(void)
{
__set_MSP(*application_start_address); // re-base the Stack Pointer
SCB->VTOR = ((uint32_t) application_start_address & SCB_VTOR_TBLOFF_Msk); // re-base the vector table base address
asm("bx %0"::"r"(*(application_start_address + 1))); // jump to application Reset Handler in the application */
}
#if defined(SYSMOOCTSIM)
/* Section 9.6 of SAMD5x/E5x Family Data Sheet */
static int get_chip_unique_serial(uint8_t *out, size_t len)
{
uint32_t *out32 = (uint32_t *)out;
if (len < 16)
return -EINVAL;
out32[0] = *(uint32_t *)0x008061fc;
out32[1] = *(uint32_t *)0x00806010;
out32[2] = *(uint32_t *)0x00806014;
out32[3] = *(uint32_t *)0x00806018;
return 0;
}
/* same as get_chip_unique_serial but in hex-string format */
static int get_chip_unique_serial_str(char *out, size_t len)
{
uint8_t buf[16];
int rc;
if (len < 16*2 + 1)
return -EINVAL;
rc = get_chip_unique_serial(buf, sizeof(buf));
if (rc < 0)
return rc;
for (int i = 0; i < sizeof(buf); i++)
sprintf(&out[i*2], "%02x", buf[i]);
return 0;
}
static int str_to_usb_desc(char* in, uint8_t in_sz, uint8_t* out, uint8_t out_sz){
if (2+in_sz*2 < out_sz)
return -1;
memset(out, 0, out_sz);
out[0] = out_sz;
out[1] = 0x3;
for (int i= 2; i < out_sz; i+=2)
out[i] = in[(i >> 1) - 1];
return 0;
}
char sernr_buf[16*2+1];
//unicode for descriptor
uint8_t sernr_buf_descr[1+1+16*2*2];
#endif
int main(void)
{
atmel_start_init(); // initialise system
#if defined(SYSMOOCTSIM)
get_chip_unique_serial_str(sernr_buf, sizeof(sernr_buf));
str_to_usb_desc(sernr_buf, sizeof(sernr_buf), sernr_buf_descr, sizeof(sernr_buf_descr));
#endif
if (!check_bootloader()) { // check bootloader
// blink the LED to tell the user we don't know where the application starts
while (true) {
gpio_set_pin_level(LED_SYSTEM, false);
delay_ms(500);
gpio_set_pin_level(LED_SYSTEM, true);
delay_ms(500);
}
}
if (!check_force_dfu() && check_application()) { // application is valid
start_application(); // start application
} else {
if (!check_application()) { // if the application is corrupted the start DFU start should be dfuERROR
dfu_state = USB_DFU_STATE_DFU_ERROR;
}
usb_dfu(); // start DFU bootloader
}
}