7 files changed, 339 insertions, 0 deletions

diff --git a/examples/boot/bootloader/stm32wba-dfu/.cargo/config.toml b/examples/boot/bootloader/stm32wba-dfu/.cargo/config.toml
new file mode 100644
index 000000000..1896068d8
--- /dev/null
+++ b/examples/boot/bootloader/stm32wba-dfu/.cargo/config.toml
@@ -0,0 +1,8 @@
+[target.'cfg(all(target_arch = "arm", target_os = "none"))']
+runner = "probe-rs run --chip STM32WBA65RI"
+
+[build]
+target = "thumbv8m.main-none-eabihf"
+
+[env]
+DEFMT_LOG = "trace"
diff --git a/examples/boot/bootloader/stm32wba-dfu/Cargo.toml b/examples/boot/bootloader/stm32wba-dfu/Cargo.toml
new file mode 100644
index 000000000..9240d1808
--- /dev/null
+++ b/examples/boot/bootloader/stm32wba-dfu/Cargo.toml
@@ -0,0 +1,64 @@
+[package]
+edition = "2021"
+name = "stm32wba6-dfu-bootloader-example"
+version = "0.1.0"
+description = "Example USB DFUbootloader for the STM32WBA series of chips"
+license = "MIT OR Apache-2.0"
+
+[dependencies]
+defmt = { version = "1.0.1", optional = true }
+defmt-rtt = { version = "1.0.0", optional = true }
+
+embassy-stm32 = { path = "../../../../embassy-stm32", features = [] }
+embassy-boot-stm32 = { path = "../../../../embassy-boot-stm32" }
+cortex-m = { version = "0.7.6", features = ["inline-asm", "critical-section-single-core"] }
+embassy-sync = { version = "0.7.0", path = "../../../../embassy-sync" }
+cortex-m-rt = { version = "0.7" }
+embedded-storage = "0.3.1"
+embedded-storage-async = "0.4.0"
+cfg-if = "1.0.0"
+embassy-usb-dfu = { version = "0.1.0", path = "../../../../embassy-usb-dfu", features = ["dfu", "cortex-m"] }
+embassy-usb = { version = "0.5.0", path = "../../../../embassy-usb", default-features = false }
+embassy-futures = { version = "0.1.1", path = "../../../../embassy-futures" }
+
+[features]
+defmt = [
+    "dep:defmt",
+    "dep:defmt-rtt",
+    "embassy-boot-stm32/defmt",
+    "embassy-stm32/defmt",
+    "embassy-usb/defmt",
+    "embassy-usb-dfu/defmt"
+]
+verify = ["embassy-usb-dfu/ed25519-salty"]
+
+[profile.dev]
+debug = 2
+debug-assertions = true
+incremental = false
+opt-level = 'z'
+overflow-checks = true
+
+[profile.release]
+codegen-units = 1
+debug = 2
+debug-assertions = false
+incremental = false
+lto = 'fat'
+opt-level = 'z'
+overflow-checks = false
+
+# do not optimize proc-macro crates = faster builds from scratch
+[profile.dev.build-override]
+codegen-units = 8
+debug = false
+debug-assertions = false
+opt-level = 0
+overflow-checks = false
+
+[profile.release.build-override]
+codegen-units = 8
+debug = false
+debug-assertions = false
+opt-level = 0
+overflow-checks = false
diff --git a/examples/boot/bootloader/stm32wba-dfu/README.md b/examples/boot/bootloader/stm32wba-dfu/README.md
new file mode 100644
index 000000000..d50164255
--- /dev/null
+++ b/examples/boot/bootloader/stm32wba-dfu/README.md
@@ -0,0 +1,63 @@
+# Bootloader for STM32
+
+This bootloader implementation uses `embassy-boot` and `embassy-usb-dfu` to manage firmware updates and interact with the flash memory on STM32WB55 devices.
+
+## Prerequisites
+
+- Rust toolchain with `cargo` installed
+- `cargo-flash` for flashing the bootloader
+- `dfu-util` for firmware updates
+- `cargo-binutils` for binary generation
+
+## Usage
+
+### 1. Flash the Bootloader
+
+First, flash the bootloader to your device:
+
+```
+cargo flash --features embassy-stm32/stm32wba65ri --release --chip STM32WBA65RI
+```
+
+### 2. Build and Flash Application
+
+Generate your application binary and flash it using DFU:
+
+```
+cargo objcopy --release -- -O binary fw.bin
+dfu-util -d c0de:cafe -w -D fw.bin
+```
+
+### 3. Sign Updates Before Flashing (Optional)
+
+Currently, embassy-usb-dfu only supports a limited implementation of the generic support for ed25519-based update verfication in embassy-boot. This implementation assumes that a signature is simply concatenated to the end of an update binary. For more details, please see https://embassy.dev/book/#_verification and/or refer to the documentation for embassy-boot-dfu.
+
+To sign (and then verify) application updates, you will first need to generate a key pair:
+
+```
+signify-openbsd -G -n -p secrets/key.pub -s secrets/key.sec
+tail -n1 secrets/key.pub | base64 -d -i - | dd ibs=10 skip=1 > secrets/key.pub.short
+```
+
+Then you will need to sign all you binaries with the private key:
+
+```
+cargo objcopy --release -- -O binary fw.bin
+shasum -a 512 -b fw.bin | head -c128 | xxd -p -r > target/fw-hash.txt
+signify-openbsd -S -s secrets/key.sec -m target/fw-hash.txt -x target/fw-hash.sig
+cp fw.bin fw-signed.bin
+tail -n1 target/fw-hash.sig | base64 -d -i - | dd ibs=10 skip=1 >> fw-signed.bin
+dfu-util -d c0de:cafe -w -D fw-signed.bin
+```
+
+Finally, as shown in this example with the `verify` feature flag enabled, you then need to embed the public key into your bootloader so that it can verify update signatures.
+
+N.B. Please note that the exact steps above are NOT a good example of how to manage your keys securely. In a production environment, you should take great care to ensure that (at least the private key) is protected and not leaked into your version control system.
+
+## Troubleshooting
+
+- Make sure your device is in DFU mode before flashing
+- Verify the USB VID:PID matches your device (c0de:cafe)
+- Check USB connections if the device is not detected
+- Make sure the transfer size option of `dfu-util` matches the bootloader configuration. By default, `dfu-util` will use the transfer size reported by the device, but you can override it with the `-t` option if needed.
+- Make sure `control_buf` size is larger than or equal to the `usb_dfu` `BLOCK_SIZE` parameter (in this example, both are set to 4096 bytes).
diff --git a/examples/boot/bootloader/stm32wba-dfu/build.rs b/examples/boot/bootloader/stm32wba-dfu/build.rs
new file mode 100644
index 000000000..fd605991f
--- /dev/null
+++ b/examples/boot/bootloader/stm32wba-dfu/build.rs
@@ -0,0 +1,27 @@
+use std::env;
+use std::fs::File;
+use std::io::Write;
+use std::path::PathBuf;
+
+fn main() {
+    // Put `memory.x` in our output directory and ensure it's
+    // on the linker search path.
+    let out = &PathBuf::from(env::var_os("OUT_DIR").unwrap());
+    File::create(out.join("memory.x"))
+        .unwrap()
+        .write_all(include_bytes!("memory.x"))
+        .unwrap();
+    println!("cargo:rustc-link-search={}", out.display());
+
+    // By default, Cargo will re-run a build script whenever
+    // any file in the project changes. By specifying `memory.x`
+    // here, we ensure the build script is only re-run when
+    // `memory.x` is changed.
+    println!("cargo:rerun-if-changed=memory.x");
+
+    println!("cargo:rustc-link-arg-bins=--nmagic");
+    println!("cargo:rustc-link-arg-bins=-Tlink.x");
+    if env::var("CARGO_FEATURE_DEFMT").is_ok() {
+        println!("cargo:rustc-link-arg-bins=-Tdefmt.x");
+    }
+}
diff --git a/examples/boot/bootloader/stm32wba-dfu/memory.x b/examples/boot/bootloader/stm32wba-dfu/memory.x
new file mode 100644
index 000000000..105c9e960
--- /dev/null
+++ b/examples/boot/bootloader/stm32wba-dfu/memory.x
@@ -0,0 +1,18 @@
+MEMORY
+{
+  /* NOTE 1 K = 1 KiBi = 1024 bytes */
+  FLASH                             : ORIGIN = 0x08000000, LENGTH = 80K
+  BOOTLOADER_STATE                  : ORIGIN = 0x08014000, LENGTH = 8K
+  ACTIVE                            : ORIGIN = 0x08016000, LENGTH = 120K
+  DFU                               : ORIGIN = 0x0803C000, LENGTH = 160K
+  RAM                         (rwx) : ORIGIN = 0x20000000, LENGTH = 400K
+}
+
+__bootloader_state_start = ORIGIN(BOOTLOADER_STATE) - ORIGIN(FLASH);
+__bootloader_state_end = ORIGIN(BOOTLOADER_STATE) + LENGTH(BOOTLOADER_STATE) - ORIGIN(FLASH);
+
+__bootloader_active_start = ORIGIN(ACTIVE) - ORIGIN(FLASH);
+__bootloader_active_end = ORIGIN(ACTIVE) + LENGTH(ACTIVE) - ORIGIN(FLASH);
+
+__bootloader_dfu_start = ORIGIN(DFU) - ORIGIN(FLASH);
+__bootloader_dfu_end = ORIGIN(DFU) + LENGTH(DFU) - ORIGIN(FLASH);
\ No newline at end of file
diff --git a/examples/boot/bootloader/stm32wba-dfu/secrets/key.pub.short b/examples/boot/bootloader/stm32wba-dfu/secrets/key.pub.short
new file mode 100644
index 000000000..7a4de8585
--- /dev/null
+++ b/examples/boot/bootloader/stm32wba-dfu/secrets/key.pub.short
@@ -0,0 +1 @@
+gB��p�M�S��z��Kg��!�F���!4�r
\ No newline at end of file
diff --git a/examples/boot/bootloader/stm32wba-dfu/src/main.rs b/examples/boot/bootloader/stm32wba-dfu/src/main.rs
new file mode 100644
index 000000000..75d8d4199
--- /dev/null
+++ b/examples/boot/bootloader/stm32wba-dfu/src/main.rs
@@ -0,0 +1,158 @@
+#![no_std]
+#![no_main]
+
+use core::cell::RefCell;
+
+use cortex_m_rt::{entry, exception};
+#[cfg(feature = "defmt")]
+use defmt_rtt as _;
+use embassy_boot_stm32::*;
+use embassy_stm32::flash::{Flash, BANK1_REGION, WRITE_SIZE};
+use embassy_stm32::usb::Driver;
+use embassy_stm32::{bind_interrupts, peripherals, usb, Config};
+use embassy_sync::blocking_mutex::Mutex;
+use embassy_usb::{msos, Builder};
+use embassy_usb_dfu::consts::DfuAttributes;
+use embassy_usb_dfu::{usb_dfu, Control, ResetImmediate};
+
+bind_interrupts!(struct Irqs {
+    USB_OTG_HS => usb::InterruptHandler<peripherals::USB_OTG_HS>;
+});
+
+// This is a randomly generated GUID to allow clients on Windows to find your device.
+//
+// N.B. update to a custom GUID for your own device!
+const DEVICE_INTERFACE_GUIDS: &[&str] = &["{EAA9A5DC-30BA-44BC-9232-606CDC875321}"];
+
+// This is a randomly generated example key.
+//
+// N.B. Please replace with your own!
+#[cfg(feature = "verify")]
+static PUBLIC_SIGNING_KEY: &[u8; 32] = include_bytes!("../secrets/key.pub.short");
+
+#[entry]
+fn main() -> ! {
+    let mut config = Config::default();
+
+    {
+        use embassy_stm32::rcc::*;
+        config.rcc.pll1 = Some(Pll {
+            source: PllSource::HSI,
+            prediv: PllPreDiv::DIV1,   // PLLM = 1 → HSI / 1 = 16 MHz
+            mul: PllMul::MUL30,        // PLLN = 30 → 16 MHz * 30 = 480 MHz VCO
+            divr: Some(PllDiv::DIV5),  // PLLR = 5 → 96 MHz (Sysclk)
+            divq: Some(PllDiv::DIV10), // PLLQ = 10 → 48 MHz
+            divp: Some(PllDiv::DIV30), // PLLP = 30 → 16 MHz (USB_OTG_HS)
+            frac: Some(0),             // Fractional part (disabled)
+        });
+
+        config.rcc.ahb_pre = AHBPrescaler::DIV1;
+        config.rcc.apb1_pre = APBPrescaler::DIV1;
+        config.rcc.apb2_pre = APBPrescaler::DIV1;
+        config.rcc.apb7_pre = APBPrescaler::DIV1;
+        config.rcc.ahb5_pre = AHB5Prescaler::DIV4;
+
+        config.rcc.voltage_scale = VoltageScale::RANGE1;
+        config.rcc.mux.otghssel = mux::Otghssel::PLL1_P;
+        config.rcc.sys = Sysclk::PLL1_R;
+    }
+
+    let p = embassy_stm32::init(config);
+
+    // Prevent a hard fault when accessing flash 'too early' after boot.
+    #[cfg(feature = "defmt")]
+    for _ in 0..10000000 {
+        cortex_m::asm::nop();
+    }
+
+    let layout = Flash::new_blocking(p.FLASH).into_blocking_regions();
+    let flash = Mutex::new(RefCell::new(layout.bank1_region));
+
+    let config = BootLoaderConfig::from_linkerfile_blocking(&flash, &flash, &flash);
+    let active_offset = config.active.offset();
+    let bl = BootLoader::prepare::<_, _, _, 2048>(config);
+
+    // Create the driver, from the HAL.
+    let mut ep_out_buffer = [0u8; 256];
+    let mut config = embassy_stm32::usb::Config::default();
+
+    config.vbus_detection = false;
+
+    if bl.state == State::DfuDetach {
+        let driver = Driver::new_hs(p.USB_OTG_HS, Irqs, p.PD6, p.PD7, &mut ep_out_buffer, config);
+        let mut config = embassy_usb::Config::new(0xc0de, 0xcafe);
+        config.manufacturer = Some("Embassy");
+        config.product = Some("USB-DFU Bootloader example");
+        config.serial_number = Some("1235678");
+
+        let fw_config = FirmwareUpdaterConfig::from_linkerfile_blocking(&flash, &flash);
+        let mut buffer = AlignedBuffer([0; WRITE_SIZE]);
+        let updater = BlockingFirmwareUpdater::new(fw_config, &mut buffer.0[..]);
+
+        let mut config_descriptor = [0; 256];
+        let mut bos_descriptor = [0; 256];
+        let mut control_buf = [0; 4096];
+
+        #[cfg(not(feature = "verify"))]
+        let mut state = Control::new(updater, DfuAttributes::CAN_DOWNLOAD, ResetImmediate);
+
+        #[cfg(feature = "verify")]
+        let mut state = Control::new(updater, DfuAttributes::CAN_DOWNLOAD, ResetImmediate, PUBLIC_SIGNING_KEY);
+
+        let mut builder = Builder::new(
+            driver,
+            config,
+            &mut config_descriptor,
+            &mut bos_descriptor,
+            &mut [],
+            &mut control_buf,
+        );
+
+        // We add MSOS headers so that the device automatically gets assigned the WinUSB driver on Windows.
+        // Otherwise users need to do this manually using a tool like Zadig.
+        //
+        // It seems these always need to be at added at the device level for this to work and for
+        // composite devices they also need to be added on the function level (as shown later).
+
+        builder.msos_descriptor(msos::windows_version::WIN8_1, 2);
+        builder.msos_feature(msos::CompatibleIdFeatureDescriptor::new("WINUSB", ""));
+        builder.msos_feature(msos::RegistryPropertyFeatureDescriptor::new(
+            "DeviceInterfaceGUIDs",
+            msos::PropertyData::RegMultiSz(DEVICE_INTERFACE_GUIDS),
+        ));
+
+        usb_dfu::<_, _, _, _, 4096>(&mut builder, &mut state, |func| {
+            // You likely don't have to add these function level headers if your USB device is not composite
+            // (i.e. if your device does not expose another interface in addition to DFU)
+            func.msos_feature(msos::CompatibleIdFeatureDescriptor::new("WINUSB", ""));
+            func.msos_feature(msos::RegistryPropertyFeatureDescriptor::new(
+                "DeviceInterfaceGUIDs",
+                msos::PropertyData::RegMultiSz(DEVICE_INTERFACE_GUIDS),
+            ));
+        });
+
+        let mut dev = builder.build();
+        embassy_futures::block_on(dev.run());
+    }
+
+    unsafe { bl.load(BANK1_REGION.base + active_offset) }
+}
+
+#[no_mangle]
+#[cfg_attr(target_os = "none", link_section = ".HardFault.user")]
+unsafe extern "C" fn HardFault() {
+    cortex_m::peripheral::SCB::sys_reset();
+}
+
+#[exception]
+unsafe fn DefaultHandler(_: i16) -> ! {
+    const SCB_ICSR: *const u32 = 0xE000_ED04 as *const u32;
+    let irqn = core::ptr::read_volatile(SCB_ICSR) as u8 as i16 - 16;
+
+    panic!("DefaultHandler #{:?}", irqn);
+}
+
+#[panic_handler]
+fn panic(_info: &core::panic::PanicInfo) -> ! {
+    cortex_m::asm::udf();
+}