Replace old BLOCK_SIZES with definitions of the blocks themselves

The actual block definitions only exist within Python classes so this
commit uses PyO3 to import the esptool.py eFuse block definitions and
generates arrays of the length and read address of each eFuse block.

We need the actual read address here rather than using the old offset
method because not all eFuse blocks are sequential.  (On ESP32 the block
0 read registers are followed by the block 0 write registers.)

Author: kyrias

CHANGELOG.md

@@ -17,7 +17,7 @@ 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)
+- Corrected eFuse block address calculations. (#971)
 - Fixed Secure Download Mode detection on ESP32-P4 (#972)
 - Several fixes in `read_efuse` (#969)
 

Cargo.lock

@@ -363,6 +363,10 @@ pub enum Error {
     /// The efuse field is larger than 32 bit.
     #[error("Requested efuse field is larger than 32 bit. Use `read_efuse_le`.")]
     EfuseFieldTooLarge,
+
+    /// Specified eFuse block does not exist
+    #[error("specified eFuse block does not exist: {0}")]
+    InvalidEfuseBlock(u32),
 }
 
 #[cfg(feature = "serialport")]

espflash/src/error.rs

@@ -2,15 +2,32 @@
 //!
 //! This file was automatically generated, please do not edit it manually!
 //!
-//! Generated: 2025-11-19 12:31
+//! Generated: 2025-11-26 21:42
 //! Version:   369d2d860d34e777c0f7d545a7dfc3c4
 
 #![allow(unused)]
 
-use super::EfuseField;
+use super::{EfuseBlock, EfuseField};
 
-/// Total size in bytes of each block
-pub(crate) const BLOCK_SIZES: &[u32] = &[28, 32, 32, 32];
+/// All eFuse blocks available on this device.
+pub(crate) const BLOCKS: &[EfuseBlock] = &[
+    EfuseBlock {
+        length: 7u8,
+        read_address: 1073061888u32,
+    },
+    EfuseBlock {
+        length: 8u8,
+        read_address: 1073061944u32,
+    },
+    EfuseBlock {
+        length: 8u8,
+        read_address: 1073061976u32,
+    },
+    EfuseBlock {
+        length: 8u8,
+        read_address: 1073062008u32,
+    },
+];
 
 /// Efuse write disable mask
 pub const WR_DIS: EfuseField = EfuseField::new(0, 0, 0, 16);

espflash/src/target/efuse/esp32.rs

@@ -2,15 +2,32 @@
 //!
 //! This file was automatically generated, please do not edit it manually!
 //!
-//! Generated: 2025-11-19 12:31
+//! Generated: 2025-11-26 21:42
 //! Version:   897499b0349a608b895d467abbcf006b
 
 #![allow(unused)]
 
-use super::EfuseField;
+use super::{EfuseBlock, EfuseField};
 
-/// Total size in bytes of each block
-pub(crate) const BLOCK_SIZES: &[u32] = &[8, 12, 32, 32];
+/// All eFuse blocks available on this device.
+pub(crate) const BLOCKS: &[EfuseBlock] = &[
+    EfuseBlock {
+        length: 2u8,
+        read_address: 1610647596u32,
+    },
+    EfuseBlock {
+        length: 3u8,
+        read_address: 1610647604u32,
+    },
+    EfuseBlock {
+        length: 8u8,
+        read_address: 1610647616u32,
+    },
+    EfuseBlock {
+        length: 8u8,
+        read_address: 1610647648u32,
+    },
+];
 
 /// Disable programming of individual eFuses
 pub const WR_DIS: EfuseField = EfuseField::new(0, 0, 0, 8);

espflash/src/target/efuse/esp32c2.rs

@@ -2,15 +2,60 @@
 //!
 //! This file was automatically generated, please do not edit it manually!
 //!
-//! Generated: 2025-11-19 12:31
+//! Generated: 2025-11-26 21:42
 //! Version:   4622cf9245401eca0eb1df8122449a6d
 
 #![allow(unused)]
 
-use super::EfuseField;
+use super::{EfuseBlock, EfuseField};
 
-/// Total size in bytes of each block
-pub(crate) const BLOCK_SIZES: &[u32] = &[24, 24, 32, 32, 32, 32, 32, 32, 32, 32, 32];
+/// All eFuse blocks available on this device.
+pub(crate) const BLOCKS: &[EfuseBlock] = &[
+    EfuseBlock {
+        length: 6u8,
+        read_address: 1610647596u32,
+    },
+    EfuseBlock {
+        length: 6u8,
+        read_address: 1610647620u32,
+    },
+    EfuseBlock {
+        length: 8u8,
+        read_address: 1610647644u32,
+    },
+    EfuseBlock {
+        length: 8u8,
+        read_address: 1610647676u32,
+    },
+    EfuseBlock {
+        length: 8u8,
+        read_address: 1610647708u32,
+    },
+    EfuseBlock {
+        length: 8u8,
+        read_address: 1610647740u32,
+    },
+    EfuseBlock {
+        length: 8u8,
+        read_address: 1610647772u32,
+    },
+    EfuseBlock {
+        length: 8u8,
+        read_address: 1610647804u32,
+    },
+    EfuseBlock {
+        length: 8u8,
+        read_address: 1610647836u32,
+    },
+    EfuseBlock {
+        length: 8u8,
+        read_address: 1610647868u32,
+    },
+    EfuseBlock {
+        length: 8u8,
+        read_address: 1610647900u32,
+    },
+];
 
 /// Disable programming of individual eFuses
 pub const WR_DIS: EfuseField = EfuseField::new(0, 0, 0, 32);

espflash/src/target/efuse/esp32c3.rs

@@ -2,15 +2,60 @@
 //!
 //! This file was automatically generated, please do not edit it manually!
 //!
-//! Generated: 2025-11-19 12:31
+//! Generated: 2025-11-26 21:42
 //! Version:   31c7fe3f5f4e0a55b178a57126c0aca7
 
 #![allow(unused)]
 
-use super::EfuseField;
+use super::{EfuseBlock, EfuseField};
 
-/// Total size in bytes of each block
-pub(crate) const BLOCK_SIZES: &[u32] = &[24, 24, 32, 32, 32, 32, 32, 32, 32, 32, 32];
+/// All eFuse blocks available on this device.
+pub(crate) const BLOCKS: &[EfuseBlock] = &[
+    EfuseBlock {
+        length: 6u8,
+        read_address: 1611352108u32,
+    },
+    EfuseBlock {
+        length: 6u8,
+        read_address: 1611352132u32,
+    },
+    EfuseBlock {
+        length: 8u8,
+        read_address: 1611352156u32,
+    },
+    EfuseBlock {
+        length: 8u8,
+        read_address: 1611352188u32,
+    },
+    EfuseBlock {
+        length: 8u8,
+        read_address: 1611352220u32,
+    },
+    EfuseBlock {
+        length: 8u8,
+        read_address: 1611352252u32,
+    },
+    EfuseBlock {
+        length: 8u8,
+        read_address: 1611352284u32,
+    },
+    EfuseBlock {
+        length: 8u8,
+        read_address: 1611352316u32,
+    },
+    EfuseBlock {
+        length: 8u8,
+        read_address: 1611352348u32,
+    },
+    EfuseBlock {
+        length: 8u8,
+        read_address: 1611352380u32,
+    },
+    EfuseBlock {
+        length: 8u8,
+        read_address: 1611352412u32,
+    },
+];
 
 /// Disable programming of individual eFuses
 pub const WR_DIS: EfuseField = EfuseField::new(0, 0, 0, 32);