Address reviews

5 files changed, 213 insertions, 0 deletions

diff --git a/examples/boot/bootloader/stm32wb-dfu/Cargo.toml b/examples/boot/bootloader/stm32wb-dfu/Cargo.toml
new file mode 100644
index 000000000..774a8223d
--- /dev/null
+++ b/examples/boot/bootloader/stm32wb-dfu/Cargo.toml
@@ -0,0 +1,63 @@
+[package]
+edition = "2021"
+name = "stm32-bootloader-example"
+version = "0.1.0"
+description = "Example bootloader for STM32 chips"
+license = "MIT OR Apache-2.0"
+
+[dependencies]
+defmt = { version = "0.3", optional = true }
+defmt-rtt = { version = "0.4", optional = true }
+
+embassy-stm32 = { path = "../../../../embassy-stm32", features = ["stm32wb55rg"] }
+embassy-boot-stm32 = { path = "../../../../embassy-boot/stm32" }
+cortex-m = { version = "0.7.6", features = ["inline-asm", "critical-section-single-core"] }
+embassy-sync = { version = "0.5.0", 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 = ["bootloader"] }
+embassy-usb = { version = "0.1.0", path = "../../../../embassy-usb", default-features = false }
+embassy-futures = { version = "0.1.1", path = "../../../../embassy-futures" }
+
+[features]
+defmt = [
+    "dep:defmt",
+    "embassy-boot-stm32/defmt",
+    "embassy-stm32/defmt",
+    "embassy-usb/defmt",
+    "embassy-usb-dfu/defmt"
+]
+debug = ["defmt-rtt", "defmt"]
+
+[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/stm32wb-dfu/README.md b/examples/boot/bootloader/stm32wb-dfu/README.md
new file mode 100644
index 000000000..a82b730b9
--- /dev/null
+++ b/examples/boot/bootloader/stm32wb-dfu/README.md
@@ -0,0 +1,11 @@
+# Bootloader for STM32
+
+The bootloader uses `embassy-boot` to interact with the flash.
+
+# Usage
+
+Flash the bootloader
+
+```
+cargo flash --features embassy-stm32/stm32wl55jc-cm4 --release --chip STM32WLE5JCIx
+```
diff --git a/examples/boot/bootloader/stm32wb-dfu/build.rs b/examples/boot/bootloader/stm32wb-dfu/build.rs
new file mode 100644
index 000000000..fd605991f
--- /dev/null
+++ b/examples/boot/bootloader/stm32wb-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/stm32wb-dfu/memory.x b/examples/boot/bootloader/stm32wb-dfu/memory.x
new file mode 100644
index 000000000..b6f185ef7
--- /dev/null
+++ b/examples/boot/bootloader/stm32wb-dfu/memory.x
@@ -0,0 +1,18 @@
+MEMORY
+{
+  /* NOTE 1 K = 1 KiBi = 1024 bytes */
+  FLASH                             : ORIGIN = 0x08000000, LENGTH = 24K
+  BOOTLOADER_STATE                  : ORIGIN = 0x08006000, LENGTH = 4K
+  ACTIVE                            : ORIGIN = 0x08008000, LENGTH = 32K
+  DFU                               : ORIGIN = 0x08010000, LENGTH = 36K
+  RAM                         (rwx) : ORIGIN = 0x20000000, LENGTH = 16K
+}
+
+__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);
diff --git a/examples/boot/bootloader/stm32wb-dfu/src/main.rs b/examples/boot/bootloader/stm32wb-dfu/src/main.rs
new file mode 100644
index 000000000..a2b884770
--- /dev/null
+++ b/examples/boot/bootloader/stm32wb-dfu/src/main.rs
@@ -0,0 +1,94 @@
+#![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::rcc::WPAN_DEFAULT;
+use embassy_stm32::usb::Driver;
+use embassy_stm32::{bind_interrupts, peripherals, usb};
+use embassy_sync::blocking_mutex::Mutex;
+use embassy_usb::Builder;
+use embassy_usb_dfu::consts::DfuAttributes;
+use embassy_usb_dfu::{usb_dfu, Control};
+
+bind_interrupts!(struct Irqs {
+    USB_LP => usb::InterruptHandler<peripherals::USB>;
+});
+
+#[entry]
+fn main() -> ! {
+    let mut config = embassy_stm32::Config::default();
+    config.rcc = WPAN_DEFAULT;
+    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);
+    let active_offset = config.active.offset();
+    let bl = BootLoader::prepare::<_, _, _, 2048>(config);
+    if bl.state == State::DfuDetach {
+        let driver = Driver::new(p.USB, Irqs, p.PA12, p.PA11);
+        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);
+        let mut buffer = AlignedBuffer([0; WRITE_SIZE]);
+        let updater = BlockingFirmwareUpdater::new(fw_config, &mut buffer.0[..]);
+
+        let mut device_descriptor = [0; 256];
+        let mut config_descriptor = [0; 256];
+        let mut bos_descriptor = [0; 256];
+        let mut control_buf = [0; 4096];
+        let mut state = Control::new(updater, DfuAttributes::CAN_DOWNLOAD);
+        let mut builder = Builder::new(
+            driver,
+            config,
+            &mut device_descriptor,
+            &mut config_descriptor,
+            &mut bos_descriptor,
+            &mut [],
+            &mut control_buf,
+        );
+
+        usb_dfu::<_, _, _, 4096>(&mut builder, &mut state);
+
+        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();
+}