Add support for programming AVR EEPROM memory if .eeprom section foun…

ravedude/Cargo.toml

@@ -17,6 +17,7 @@ serialport = "4.0.0"
 anyhow = "1.0.38"
 git-version = "0.3.4"
 ctrlc = "3.2.1"
+elf = "0.7.2"
 
 [dependencies.structopt]
 version = "0.3.21"

ravedude/src/avrdude/mod.rs

@@ -49,6 +49,7 @@ impl Avrdude {
 
     pub fn run(
         options: &AvrdudeOptions,
+        do_eeprom: bool,
         port: Option<impl AsRef<path::Path>>,
         bin: &path::Path,
     ) -> anyhow::Result<Self> {
@@ -95,6 +96,26 @@ impl Avrdude {
 
         command = command.arg("-D").arg("-U").arg(flash_instruction);
 
+        // Check whether we should program the EEPROM. The command can be
+        // appended to the command-line, but avrdude will return with a
+        // nonzero error code if the ELF file didn't have an `.eeprom` section.
+        // So we conditionally add it.
+        if do_eeprom {
+            let fp = std::fs::File::open(bin).context("could not read ELF file")?;
+            let mut elf = elf::ElfStream::<elf::endian::LittleEndian, _>::open_stream(fp).context("parsing ELF file failed")?;
+
+            if elf.section_header_by_name(".eeprom")
+                  .context("error parsing ELF section headers")?
+                  .is_some()
+            {
+                let mut eeprom_instruction: std::ffi::OsString = "eeprom:w:".into();
+                eeprom_instruction.push(bin);
+                eeprom_instruction.push(":e");
+
+                command = command.arg("-U").arg(eeprom_instruction);
+            }
+        }
+
         let process = command.spawn().context("failed starting avrdude")?;
 
         Ok(Self { config, process })

ravedude/src/main.rs

@@ -33,6 +33,11 @@ struct Args {
     #[structopt(short = "c", long = "open-console")]
     open_console: bool,
 
+    /// Skip flashing .eeprom section to AVR EEPROM. Default is to auto-detect
+    /// an .eeprom section.
+    #[structopt(short = "s", long = "skip-eeprom")]
+    skip_eeprom: bool,
+
     /// Baudrate which should be used for the serial console.
     #[structopt(short = "b", long = "baudrate")]
     baudrate: Option<u32>,
@@ -135,7 +140,7 @@ fn ravedude() -> anyhow::Result<()> {
             task_message!("Programming", "{}", bin.display(),);
         }
 
-        let mut avrdude = avrdude::Avrdude::run(&board.avrdude_options(), port.as_ref(), bin)?;
+        let mut avrdude = avrdude::Avrdude::run(&board.avrdude_options(), !args.skip_eeprom, port.as_ref(), bin)?;
         avrdude.wait()?;
 
         task_message!("Programmed", "{}", bin.display());