fix unexpected address on multi-section writing

CHANGELOG.md

@@ -10,6 +10,7 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 ### Fixed
 
 - Rename ChipUID response to ESignature, #58
+- Add `--skip-gap` as a experimental option for `flash` subcommand to write a firmware which has more than 1 section, #40 & #56
 
 ## [0.0.8] - 2024-03-30
 
@@ -22,10 +23,6 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 - Use loaded memory address from ELF file or ihex file
 - Add timestamp in serial output
 
-### Fixed
-
-- Merge gaps in firmware sections, #56
-
 ### Changed
 
 - No erase by default when flashing

src/firmware.rs

@@ -38,39 +38,35 @@ pub enum Firmware {
     Sections(Vec<Section>),
 }
 
-impl Firmware {
-    /// Merge sections, and fill gap with 0xff
-    pub fn merge_sections(self) -> Result<Self> {
-        if let Firmware::Sections(mut sections) = self {
-            sections.sort_by_key(|s| s.address);
-            let mut merged = vec![];
-
-            let mut it = sections.drain(0..);
-            let mut last = it
-                .next()
-                .expect("firmware must has at least one section; qed");
-
-            for sect in it {
-                if let Some(gap) = sect.address.checked_sub(last.end_address()) {
-                    if gap > 0 {
-                        log::debug!("Merge firmware sections with gap: {}", gap);
-                    }
-                    last.data.resize(last.data.len() + gap as usize, 0xff); // fill gap with 0xff
-                    last.data.extend_from_slice(&sect.data);
-                } else {
-                    return Err(anyhow::format_err!(
-                        "section address overflow: {:#010x} + {:#x}",
-                        last.address,
-                        last.data.len()
-                    ));
-                }
+/// Merge sections w/ <= max_tiny_gap bytes gap
+pub fn fill_tiny_gap_between_sections(mut sections: Vec<Section>, max_tiny_gap: u32) -> Result<Vec<Section>> {
+    sections.sort_by_key(|s| s.address);
+    let mut merged = vec![];
+
+    let mut it = sections.drain(0..);
+    let mut last = it
+        .next()
+        .expect("firmware must has at least one section; qed");
+    for sect in it {
+        if let Some(gap) = sect.address.checked_sub(last.end_address()) {
+            if gap > max_tiny_gap {
+                merged.push(last);
+                last = sect.clone();
+                continue;
+            } else {
+                last.data.resize(last.data.len() + gap as usize, 0xFF);
+                last.data.extend_from_slice(&sect.data);
             }
-            merged.push(last);
-            Ok(Firmware::Sections(merged))
         } else {
-            Ok(self)
+            return Err(anyhow::format_err!(
+                    "section address overflow: {:#010x} + {:#x}",
+                    last.address,
+                    last.data.len()
+                ));
         }
     }
+    merged.push(last);
+    Ok(merged)
 }
 
 pub fn read_firmware_from_file<P: AsRef<Path>>(path: P) -> Result<Firmware> {
@@ -90,9 +86,9 @@ pub fn read_firmware_from_file<P: AsRef<Path>>(path: P) -> Result<Firmware> {
         }
         FirmwareFormat::Binary => Ok(Firmware::Binary(raw)),
         FirmwareFormat::IntelHex => {
-            read_ihex(str::from_utf8(&raw)?).and_then(|f| f.merge_sections())
+            read_ihex(str::from_utf8(&raw)?)
         }
-        FirmwareFormat::ELF => read_elf(&raw).and_then(|f| f.merge_sections()),
+        FirmwareFormat::ELF => read_elf(&raw),
     }
 }
 

src/main.rs

@@ -4,7 +4,7 @@ use anyhow::Result;
 use wlink::{
     commands,
     dmi::DebugModuleInterface,
-    firmware::{read_firmware_from_file, Firmware},
+    firmware::{fill_tiny_gap_between_sections, read_firmware_from_file, Firmware},
     operations::ProbeSession,
     probe::WchLink,
     regs, RiscvChip,
@@ -93,6 +93,9 @@ enum Commands {
         /// Erase flash before flashing
         #[arg(long, short, default_value = "false")]
         erase: bool,
+        /// Skip gap between sections
+        #[arg(long, short, default_value = "false")]
+        skip_gap: bool,
         /// Do not reset and run after flashing
         #[arg(long, short = 'R', default_value = "false")]
         no_run: bool,
@@ -325,6 +328,7 @@ fn main() -> Result<()> {
                 Flash {
                     address,
                     erase,
+                    skip_gap,
                     no_run,
                     path,
                     enable_sdi_print,
@@ -341,25 +345,38 @@ fn main() -> Result<()> {
 
                     match firmware {
                         Firmware::Binary(data) => {
+                            if skip_gap {
+                                log::warn!("Skip gap is ignored when flashing binary");
+                            }
                             let start_address =
                                 address.unwrap_or_else(|| sess.chip_family.code_flash_start());
                             log::info!("Flashing {} bytes to 0x{:08x}", data.len(), start_address);
                             sess.write_flash(&data, start_address)?;
                         }
                         Firmware::Sections(sections) => {
-                            // Flash section by section
+                            let mut sections = sections.clone();
                             if address != None {
                                 log::warn!("--address is ignored when flashing ELF or ihex");
                             }
+                            if skip_gap {
+                                log::warn!("Skip gap is a experimental feature using a trait of wchlink!");
+                                sections = fill_tiny_gap_between_sections(sections, 4096)?;
+                            } else {
+                                // merge sections
+                                sections = fill_tiny_gap_between_sections(sections, 0xFFFFFFFF)?;
+                            }
+                            let mut offset = 0; // may a trait of wchlink
                             for section in sections {
                                 let start_address =
                                     sess.chip_family.fix_code_flash_start(section.address);
                                 log::info!(
-                                    "Flashing {} bytes to 0x{:08x}",
-                                    section.data.len(),
-                                    start_address
-                                );
-                                sess.write_flash(&section.data, start_address)?;
+                                        "Flashing {} bytes to 0x{:08x}",
+                                        section.data.len(),
+                                        start_address
+                                    );
+                                log::debug!("offset: 0x{:08x}", offset);
+                                sess.write_flash(&section.data, start_address - offset)?;
+                                offset += ((section.data.len() as u32 + 4095) / 4096) * 4096;
                             }
                         }
                     }