eFuse write support

CHANGELOG.md

@@ -13,6 +13,8 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 
 ### Fixed
 
+- Corrected eFuse BLOCK0 definitions for ESP32-C2, ESP32-C3, and ESP32-S3 (#961)
+
 ### Removed
 
 ## [4.2.0] - 2025-10-13

espflash/Cargo.toml

@@ -50,6 +50,7 @@ log             = "0.4"
 md-5            = "0.10"
 miette          = "7.6"
 object          = "0.37"
+reed-solomon    = "0.2.1"
 regex           = { version = "1.11", optional = true }
 serde           = { version = "1.0", features = ["derive"] }
 serialport      = { version = "4.7", default-features = false, optional = true }

espflash/src/connection/mod.rs

@@ -683,6 +683,15 @@ impl Connection {
         Ok(())
     }
 
+    /// Updates a register by applying the new value to the masked out portion of the old value.
+    pub fn update_reg(&mut self, addr: u32, mask:u32, new_value: u32) -> Result<(), Error> {
+        let masked_new_value = new_value.unbounded_shl(mask.trailing_zeros()) & mask;
+
+        let masked_old_value = self.read_reg(addr)? & !mask;
+
+        self.write_reg(addr, masked_old_value | masked_new_value, None)
+    }
+
     /// Reads a register command with a timeout.
     pub(crate) fn read(&mut self, len: usize) -> Result<Option<Vec<u8>>, Error> {
         let mut tmp = Vec::with_capacity(1024);

espflash/src/error.rs

@@ -357,6 +357,10 @@ pub enum Error {
     /// Key is not in the expected section
     #[error("Misplaced key, check your configuration file. Key: {0}")]
     MisplacedKey(String),
+
+    /// Failed to write eFuse
+    #[error("Failed to write eFuse: {0}")]
+    WritingEfuseFailed(String),
 }
 
 #[cfg(feature = "serialport")]