oxidecomputer · labbott · Dec 30, 2025 · Dec 30, 2025
diff --git a/app/cosmo/base.toml b/app/cosmo/base.toml
@@ -2,7 +2,6 @@ target = "thumbv7em-none-eabihf"
 chip = "../../chips/stm32h7"
 memory = "memory-large.toml"
 stacksize = 896
-fwid = true
 
 [kernel]
 name = "cosmo"

diff --git a/app/gemini-bu/app.toml b/app/gemini-bu/app.toml
@@ -3,7 +3,6 @@ target = "thumbv7em-none-eabihf"
 board = "gemini-bu-1"
 chip = "../../chips/stm32h7"
 stacksize = 896
-fwid = true
 
 [kernel]
 name = "gemini-bu"

diff --git a/app/gimlet/base.toml b/app/gimlet/base.toml
@@ -2,7 +2,6 @@ target = "thumbv7em-none-eabihf"
 chip = "../../chips/stm32h7"
 memory = "memory-large.toml"
 stacksize = 896
-fwid = true
 
 [kernel]
 name = "gimlet"

diff --git a/app/gimletlet/app-mgmt.toml b/app/gimletlet/app-mgmt.toml
@@ -3,7 +3,6 @@ target = "thumbv7em-none-eabihf"
 board = "gimletlet-1"
 chip = "../../chips/stm32h7"
 stacksize = 1024
-fwid = true
 
 [kernel]
 name = "gimletlet"

diff --git a/app/gimletlet/base-gimletlet2.toml b/app/gimletlet/base-gimletlet2.toml
@@ -5,7 +5,6 @@ memory = "memory-large.toml"
 stacksize = 896
 epoch = 0
 version = 0
-fwid = true
 
 [kernel]
 name = "gimletlet"

diff --git a/app/grapefruit/base.toml b/app/grapefruit/base.toml
@@ -5,7 +5,6 @@ memory = "memory-large.toml"
 stacksize = 896
 epoch = 0
 version = 0
-fwid = true
 
 [mmio]
 peripheral-region = "fmc_nor_psram_bank_1"

diff --git a/app/lpc55xpresso/app.toml b/app/lpc55xpresso/app.toml
@@ -4,7 +4,6 @@ board = "lpcxpresso55s69"
 chip = "../../chips/lpc55"
 stacksize = 1024
 image-names = ["a", "b"]
-fwid = true
 
 [kernel]
 name = "lpc55xpresso"

diff --git a/app/medusa/base.toml b/app/medusa/base.toml
@@ -2,7 +2,6 @@ target = "thumbv7em-none-eabihf"
 chip = "../../chips/stm32h7"
 memory = "memory-large.toml"
 stacksize = 896
-fwid = true
 
 [kernel]
 name = "medusa"

diff --git a/app/minibar/base.toml b/app/minibar/base.toml
@@ -2,7 +2,6 @@ target = "thumbv7em-none-eabihf"
 chip = "../../chips/stm32h7"
 stacksize = 896
 memory = "memory-large.toml"
-fwid = true
 
 [kernel]
 name = "minibar"

@@ -10,7 +10,6 @@ stacksize = 1024
 image-names = ["a", "b"]
 epoch = 0
 version = 0
-fwid = true
 
 [kernel]
 name = "oxide-rot-1"

@@ -7,7 +7,6 @@ stacksize = 1024
 image-names = ["a", "b"]
 epoch = 0
 version = 0
-fwid = true
 
 [kernel]
 name = "oxide-rot-1"

diff --git a/app/psc/base.toml b/app/psc/base.toml
@@ -2,7 +2,6 @@ target = "thumbv7em-none-eabihf"
 chip = "../../chips/stm32h7"
 memory = "memory-large.toml"
 stacksize = 896
-fwid = true
 
 [kernel]
 name = "psc"

diff --git a/app/rot-carrier/app.toml b/app/rot-carrier/app.toml
@@ -6,7 +6,6 @@ stacksize = 1024
 image-names = ["a", "b"]
 epoch = 0
 version = 0
-fwid = true
 
 [kernel]
 name = "rot-carrier"

diff --git a/app/sidecar/base.toml b/app/sidecar/base.toml
@@ -2,7 +2,6 @@ target = "thumbv7em-none-eabihf"
 chip = "../../chips/stm32h7"
 stacksize = 896
 memory = "memory-large.toml"
-fwid = true
 
 [kernel]
 name = "sidecar"

diff --git a/build/xtask/src/config.rs b/build/xtask/src/config.rs
@@ -28,8 +28,6 @@ struct RawConfig {
     epoch: u32,
     #[serde(default)]
     version: u32,
-    #[serde(default)]
-    fwid: bool,
     memory: Option<String>,
     #[serde(default)]
     image_names: Vec<String>,
@@ -67,7 +65,6 @@ pub struct Config {
     pub epoch: u32,
     pub mmio: Option<MmioData>,
     pub version: u32,
-    pub fwid: bool,
     pub image_names: Vec<String>,
     pub signing: Option<RoTMfgSettings>,
     pub stacksize: Option<u32>,
@@ -262,7 +259,6 @@ impl Config {
             mmio,
             epoch: toml.epoch,
             version: toml.version,
-            fwid: toml.fwid,
             signing: toml.signing,
             stacksize: toml.stacksize,
             kernel: toml.kernel,

diff --git a/build/xtask/src/dist.rs b/build/xtask/src/dist.rs
@@ -3,7 +3,6 @@
 // file, You can obtain one at https://mozilla.org/MPL/2.0/.
 
 use std::collections::{BTreeMap, BTreeSet, HashMap, VecDeque};
-use std::ffi::OsStr;
 use std::fmt::Write as _;
 use std::fs::{self, File};
 use std::hash::{Hash, Hasher};
@@ -15,10 +14,8 @@ use std::process::{Command, Stdio};
 use anyhow::{anyhow, bail, Context, Result};
 use atty::Stream;
 use indexmap::IndexMap;
-use lpc55_rom_data::FLASH_PAGE_SIZE as LPC55_FLASH_PAGE_SIZE;
 use multimap::MultiMap;
 use path_slash::{PathBufExt, PathExt};
-use sha3::{Digest, Sha3_256};
 use zerocopy::IntoBytes;
 
 use crate::{
@@ -720,10 +717,6 @@ pub fn package(
             archive.overwrite()?;
         }
 
-        if cfg.toml.fwid {
-            write_fwid(&cfg, image_name, &flash, &archive_name)?;
-        }
-
         // Unzip the signed + caboose'd images into our build directory
         let archive = hubtools::RawHubrisArchive::load(&archive_name)
             .context("loading archive with hubtools")?;
@@ -738,67 +731,6 @@ pub fn package(
     Ok(allocated)
 }
 
-// generate file with hash of expected flash contents
-fn write_fwid(
-    cfg: &PackageConfig,
-    image_name: &str,
-    flash: &Range<u32>,
-    archive_name: &PathBuf,
-) -> Result<()> {
-    let mut archive = hubtools::RawHubrisArchive::load(archive_name)
-        .context("loading archive with hubtools")?;
-
-    let bin = archive
-        .extract_file("img/final.bin")
-        .context("extracting final.bin after signing & caboosing")?;
-
-    let chip_name = Path::new(&cfg.toml.chip);
-
-    // determine length of padding
-    let pad = match chip_name.file_name().and_then(OsStr::to_str) {
-        Some("lpc55") => {
-            // Flash is programmed in 512 blocks. If the final block is not
-            // filled, it is padded with 0xff's. Unwritten flash pages cannot
-            // be read and are not included in the FWID calculation.
-            LPC55_FLASH_PAGE_SIZE - bin.len() % LPC55_FLASH_PAGE_SIZE
-        }
-        Some("stm32h7") => {
-            // all unprogrammed flash is read as 0xff
-            flash.end as usize - flash.start as usize - bin.len()
-        }
-        Some(c) => {
-            bail!("no FWID algorithm defined for chip: \"{}\"", c)
-        }
-        None => bail!("Failed to get file name of {}", chip_name.display()),
-    };
-
-    let mut sha = Sha3_256::new();
-    sha.update(&bin);
-
-    if pad != 0 {
-        sha.update(vec![0xff_u8; pad])
-    }
-
-    let digest = sha.finalize();
-
-    // after we've appended a newline fwid is immutable
-    let mut fwid = hex::encode(digest);
-    writeln!(fwid).context("appending newline to FWID")?;
-    let fwid = fwid;
-
-    // the archive already exists so we write the FWID to the same path in
-    // the build output and archive to keep the two consistent
-    fs::write(cfg.img_file("final.fwid", image_name), &fwid)
-        .context("writing FWID to build output")?;
-    archive
-        .add_file("img/final.fwid", fwid.as_bytes())
-        .context("writing FWID to archive")?;
-
-    archive.overwrite()?;
-
-    Ok(())
-}
-
 fn write_gdb_script(cfg: &PackageConfig, image_name: &str) -> Result<()> {
     // Humility doesn't know about images right now. The gdb symbol file
     // paths all assume a flat layout with everything in dist. For now,