components/bootloader_support/include/esp_efuse.h

   1 // Copyright 2015-2016 Espressif Systems (Shanghai) PTE LTD
   2 //
   3 // Licensed under the Apache License, Version 2.0 (the "License");
   4 // you may not use this file except in compliance with the License.
   5 // You may obtain a copy of the License at
   6
   7 //     http://www.apache.org/licenses/LICENSE-2.0
   8 //
   9 // Unless required by applicable law or agreed to in writing, software
  10 // distributed under the License is distributed on an "AS IS" BASIS,
  11 // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  12 // See the License for the specific language governing permissions and
  13 // limitations under the License.
  14 #ifndef _ESP_EFUSE_H
  15 #define _ESP_EFUSE_H
  16
  17 #include "soc/efuse_reg.h"
  18
  19 #ifdef __cplusplus
  20 extern "C" {
  21 #endif
  22
  23 /* @brief Permanently update values written to the efuse write registers
  24  *
  25  * After updating EFUSE_BLKx_WDATAx_REG registers with new values to
  26  * write, call this function to permanently write them to efuse.
  27  *
  28  * @note Setting bits in efuse is permanent, they cannot be unset.
  29  *
  30  * @note Due to this restriction you don't need to copy values to
  31  * Efuse write registers from the matching read registers, bits which
  32  * are set in the read register but unset in the matching write
  33  * register will be unchanged when new values are burned.
  34  *
  35  * @note This function is not threadsafe, if calling code updates
  36  * efuse values from multiple tasks then this is caller's
  37  * responsibility to serialise.
  38  *
  39  * After burning new efuses, the read registers are updated to match
  40  * the new efuse values.
  41  */
  42 void esp_efuse_burn_new_values(void);
  43
  44 /* @brief Reset efuse write registers
  45  *
  46  * Efuse write registers are written to zero, to negate
  47  * any changes that have been staged here.
  48  */
  49 void esp_efuse_reset(void);
  50
  51 /* @brief Disable BASIC ROM Console via efuse
  52  *
  53  * By default, if booting from flash fails the ESP32 will boot a
  54  * BASIC console in ROM.
  55  *
  56  * Call this function (from bootloader or app) to permanently
  57  * disable the console on this chip.
  58  */
  59 void esp_efuse_disable_basic_rom_console(void);
  60
  61 #ifdef __cplusplus
  62 }
  63 #endif
  64
  65 #endif /* __ESP_EFUSE_H */
  66