(solved) working with efuses

[mzimmers]

Hi all -

I recently started working with the efuse handler. I need to store a custom MAC address in BLK3, so I wrote the following routine:

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esp_err_t Flash::initBaseMacAddress()
{
    char macAddrAscii[18] = { NULL_CHAR };
    esp_err_t rc = ESP_OK;

    ESP_FUSE3 fuse3;

    // see whether efuse has been programmed yet.
    // (if programmed, won't be all 0s.)
    // if not programmed, do so using the flash value, and do the CRC as well.
    rc = esp_efuse_read_block(EFUSE_BLK3, &fuse3, 0, 192);
    ESP_LOGI(TAG, "initBaseMacAddress(): efuse BLK3 is programmed as follows:");
    ESP_LOGI(TAG, "initBaseMacAddress(): efuse BLK3 version field is programmed as %x: ", fuse3.version);
    ESP_LOGI(TAG, "initBaseMacAddress(): efuse BLK3 MAC field is programmed as %02x:%02x:%02x:%02x:%02x:%02x.",
             fuse3.macAddr[0], fuse3.macAddr[1], fuse3.macAddr[2],
            fuse3.macAddr[3],fuse3.macAddr[4],fuse3.macAddr[5]);
    ESP_LOGI(TAG, "initBaseMacAddress(): efuse BLK3 CRC field is programmed as %x: ", fuse3.crc);



    rc = esp_efuse_mac_get_custom(fuse3.macAddr);
    if (rc == ESP_OK)
    {
        ESP_LOGI(TAG, "taskInit(): esp_efuse_mac_get_custom returned successfully.");
        mac_itoa(fuse3.macAddr, macAddrAscii);
        setMacAddr(macAddrAscii);
    }
    else if (rc == ESP_ERR_INVALID_VERSION) // this error suggests the MAC hasn't been programmed.
    {
        ESP_LOGW(TAG, "initBaseMacAddress(): invalid version in efuse BLK3; attempting to program.");

        // fill the fields in the structure and program the fuse.
        fuse3.version = 1;                                  // anything non-zero will do for now.
        memset (fuse3.reserved, 0, sizeof(fuse3.reserved)); // make sure it's all zeroes (no write).
        strcpy(macAddrAscii, getMacAddr().c_str());       // get address in string format from flash.

        if (strcmp(macAddrAscii, NVS_INVALID))
        {
            rc = mac_atoi(fuse3.macAddr, macAddrAscii);            // convert to binary
            if (rc == ESP_OK)
            {
                fuse3.crc = crc8Maxim(fuse3.macAddr, 6);

                ESP_LOGI(TAG, "initBaseMacAddress(): programming efuse BLK3 as follows:");
                ESP_LOGI(TAG, "initBaseMacAddress(): programming efuse BLK3 version field as %x: ", fuse3.version);
                ESP_LOGI(TAG, "initBaseMacAddress(): programming efuse BLK3 MAC field as %02x:%02x:%02x:%02x:%02x:%02x.",
                         fuse3.macAddr[0], fuse3.macAddr[1], fuse3.macAddr[2],
                        fuse3.macAddr[3],fuse3.macAddr[4],fuse3.macAddr[5]);
                ESP_LOGI(TAG, "initBaseMacAddress(): programming efuse BLK3 CRC field as %x: ", fuse3.crc);

                // program fuse 3.
                rc = esp_efuse_write_block(EFUSE_BLK3, &fuse3, 0, 192);
                if (rc == ESP_OK)
                {
                    ESP_LOGI(TAG, "initBaseMacAddress(): efuse BLK3 successfully programmed.");
                    mac_itoa(fuse3.macAddr, macAddrAscii);
                    setMacAddr(macAddrAscii);
                }
                else
                {
                    ESP_LOGE(TAG, "initBaseMacAddress(): error writing custom MAC into efuse BLK3; halting execution.");
                    vTaskDelay(portMAX_DELAY);
                }
                ...

This gives me the following (unexpected) output:

I (69) Flash: initBaseMacAddress(): efuse BLK3 is programmed as follows:
I (79) Flash: initBaseMacAddress(): efuse BLK3 version field is programmed as 1:
I (89) Flash: initBaseMacAddress(): efuse BLK3 MAC field is programmed as 00:a0:d0:00:00:00.
I (99) Flash: initBaseMacAddress(): efuse BLK3 CRC field is programmed as 32:
E (109) system_api: Base MAC address from BLK3 of EFUSE version error, version = 0
W (109) Flash: initBaseMacAddress(): invalid version in efuse BLK3; attempting to program.
I (119) Flash: initBaseMacAddress(): programming efuse BLK3 as follows:
I (129) Flash: initBaseMacAddress(): programming efuse BLK3 version field as 1:
I (139) Flash: initBaseMacAddress(): programming efuse BLK3 MAC field as 12:23:34:45:56:67.
I (149) Flash: initBaseMacAddress(): programming efuse BLK3 CRC field as fa:
E (149) efuse: Repeated programming of programmed bits is strictly forbidden 0x10200032
E (159) Flash: initBaseMacAddress(): error writing custom MAC into efuse BLK3; halting execution.

Any idea what I'm doing wrong? Running V3.3.

Also, is there truly no way to reset the fuses once written? I'd like to minimize the number of devices I burn incorrectly while I troubleshoot this issue.

Thanks...

[mzimmers]

BTT...anyone have any suggestions on this?

Thanks...

[WiFive]

Are you saying that is the output on the first run meaning there are already nonzero values in block3 when you started? What is the efuse dump from esptool?

[mzimmers]

Hi WiFive - no, this isn't from the first run. In the first run, I programmed values into BLK3. But on subsequent runs, I'm getting this:

E (109) system_api: Base MAC address from BLK3 of EFUSE version error, version = 0

when I call esp_efuse_mac_get_custom(). According to the docs, that suggests the field wasn't programmed, but my program output indicates that it was.

A good starting point would be to see why I'm getting the above error, when my telltales indicate that I've programmed BLK3.

Thanks...

[WiFive]

Did you test in virtual mode https://github.com/espressif/esp-idf/bl ... config#L17

[mzimmers]

I wasn't aware of that simulation option; thank you for pointing it out. I just tried it, and got essentially the same results.

Code: Select all

I (69) Flash: initBaseMacAddress(): efuse BLK3 is programmed as follows:
I (79) Flash: initBaseMacAddress(): efuse BLK3 version field is programmed as 1:
I (89) Flash: initBaseMacAddress(): efuse BLK3 MAC field is programmed as 00:a0:d0:00:00:00.
I (99) Flash: initBaseMacAddress(): efuse BLK3 CRC field is programmed as 32:
E (109) system_api: Base MAC address from BLK3 of EFUSE version error, version = 0
W (109) Flash: initBaseMacAddress(): invalid version in efuse BLK3; attempting to program.
I (119) Flash: initBaseMacAddress(): programming efuse BLK3 as follows:
I (129) Flash: initBaseMacAddress(): programming efuse BLK3 version field as 1:
I (139) Flash: initBaseMacAddress(): programming efuse BLK3 MAC field as 12:23:34:45:56:67.
I (149) Flash: initBaseMacAddress(): programming efuse BLK3 CRC field as fa:
E (149) efuse: Repeated programming of programmed bits is strictly forbidden 0x10200032
E (159) Flash: initBaseMacAddress(): error writing custom MAC into efuse BLK3; halting execution.

So, the code seems to be doing what I want it to...I must not understand how to use the system calls properly, as I'm still getting the version error when I call:

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 rc = esp_efuse_mac_get_custom(fuse3.macAddr);

[WiFive]

What is ESP_FUSE3? Have you tried writing the fields individually?

[mzimmers]

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struct ESP_FUSE3
{
    uint8_t crc;
    uint8_t macAddr[6];
    uint8_t reserved[8];
    uint8_t version;
};

I could try writing the fields individually, but the real mystery right now is why this call:

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rc = esp_efuse_mac_get_custom(fuse3.macAddr);

Is returning ESP_ERR_INVALID_VERSION. I have shown that the version field contains a non-zero value.

[WiFive]

Do you need packed attribute to ensure struct is not padded?

[mzimmers]

I didn't think so, but I'll try again in the morning with the attribute and report back. Thanks...