ESP32 Forum

Posted: **Mon Oct 02, 2023 10:35 pm**

I am using the example custom bootloader (custombootloader_override) in the IDF examples , I have OTA in my app , I am trying to find the simplest way to change from the OTA to factory within the bootloader (if a user keeps a button pressed), I need this in case there is an error in my code in the OTA - which prevents further updates.
I do not have the expertise to mess around with partition tables etc..

here is the code from the examples...how do I change the index so it points to factory if I keep a gpio/button pressed otherwise boot as normal (from either of the 2 OTA partitions)

Many thanks in advance for your help!!

Code: [Select all] [Expand/Collapse]

/*
 * SPDX-FileCopyrightText: 2015-2021 Espressif Systems (Shanghai) CO LTD
 *
 * SPDX-License-Identifier: Apache-2.0
 */
#include <stdbool.h>
#include "sdkconfig.h"
#include "esp_log.h"
#include "bootloader_init.h"
#include "bootloader_utility.h"
#include "bootloader_common.h"
 
static const char* TAG = "boot";
 
static int select_partition_number(bootloader_state_t *bs);
 
/*
 * We arrive here after the ROM bootloader finished loading this second stage bootloader from flash.
 * The hardware is mostly uninitialized, flash cache is down and the app CPU is in reset.
 * We do have a stack, so we can do the initialization in C.
 */
void __attribute__((noreturn)) call_start_cpu0(void)
{
    // 1. Hardware initialization
    if (bootloader_init() != ESP_OK) {
        bootloader_reset();
    }
 
#ifdef CONFIG_BOOTLOADER_SKIP_VALIDATE_IN_DEEP_SLEEP
    // If this boot is a wake up from the deep sleep then go to the short way,
    // try to load the application which worked before deep sleep.
    // It skips a lot of checks due to it was done before (while first boot).
    bootloader_utility_load_boot_image_from_deep_sleep();
    // If it is not successful try to load an application as usual.
#endif
 
    // 2. Select the number of boot partition
    bootloader_state_t bs = {0};
    int boot_index = select_partition_number(&bs);
    if (boot_index == INVALID_INDEX) {
        bootloader_reset();
    }
 
    // 2.1 Print a custom message!
    esp_rom_printf("[%s] %s\n", TAG, CONFIG_EXAMPLE_BOOTLOADER_WELCOME_MESSAGE);
 
    // 3. Load the app image for booting
    bootloader_utility_load_boot_image(&bs, boot_index);
}
 
// Select the number of boot partition
static int select_partition_number(bootloader_state_t *bs)
{
    // 1. Load partition table
    if (!bootloader_utility_load_partition_table(bs)) {
        ESP_LOGE(TAG, "load partition table error!");
        return INVALID_INDEX;
    }
 
    // 2. Select the number of boot partition
    return bootloader_utility_get_selected_boot_partition(bs);
}
 
// Return global reent struct if any newlib functions are linked to bootloader
struct _reent *__getreent(void)
{
    return _GLOBAL_REENT;
}

Posted: **Mon Oct 09, 2023 3:58 am**

Simplest option here is to erase the "otadata" partition, and that shall let the boot-up fallback to the factory partition. Please refer to this guide: https://docs.espressif.com/projects/esp ... tory-reset

ESP32 Forum

custom bootloader example error when I try to change index

custom bootloader example error when I try to change index

Re: custom bootloader example error when I try to change index