Add custom halt function that restarts the system after a delay

firmware/Cargo.toml

@@ -46,7 +46,7 @@ embedded-graphics = "0.8"
 embedded-hal = "1.0"
 embedded-hal-async = "1.0"
 embedded-hal-bus = { version = "0.2", features = ["async"] }
-esp-backtrace = { version = "0.13", features = ["esp32c3", "panic-handler", "exception-handler", "println"] }
+esp-backtrace = { version = "0.13", features = ["esp32c3", "custom-halt", "panic-handler", "exception-handler", "println"] }
 esp-hal = { version = "0.19", features = ["esp32c3", "async", "log"] }
 esp-hal-embassy = { version = "0.2", features = ["esp32c3", "log"] }
 esp-println = { version = "0.10", features = ["esp32c3", "log"] }

firmware/src/main.rs

@@ -46,10 +46,12 @@ use esp_hal::i2c::I2C;
 use esp_hal::peripherals::Peripherals;
 use esp_hal::prelude::*;
 use esp_hal::rng::Rng;
+use esp_hal::rtc_cntl::Rtc;
 use esp_hal::system::SystemControl;
 use esp_hal::timer::systimer::SystemTimer;
 use esp_hal::timer::timg::TimerGroup;
 use esp_hal::timer::{ErasedTimer, OneShotTimer, PeriodicTimer};
+use esp_println::println;
 use log::info;
 
 // When you are okay with using a nightly compiler it's better to use https://docs.rs/static_cell/2.1.0/static_cell/macro.make_static.html
@@ -65,6 +67,28 @@ macro_rules! mk_static {
 static VERSION_STR: &str = concat!("v", env!("CARGO_PKG_VERSION"));
 static GIT_SHA_STR: &str = env!("GIT_SHORT_SHA");
 
+/// Custom halt function for esp-backtrace. Called after panic was handled and should halt
+/// or restart the system.
+#[export_name = "custom_halt"]
+unsafe fn halt() -> ! {
+    // System may be in any state at this time, thus everything is unsafe here. Stealing the
+    // peripherals handle allows us to try to notify the user about this abnormal state and
+    // restart the system. Any error should be ignored.
+    let peripherals = Peripherals::steal();
+
+    // TODO: Steal display driver and show a panic message to the user
+
+    // Restart automatically after a delay
+    println!("Restarting in 10 seconds...");
+    let mut rtc = Rtc::new(peripherals.LPWR, None);
+    rtc.rwdt.set_timeout(10_000.millis());
+    rtc.rwdt.unlisten();
+    rtc.rwdt.enable();
+    loop {
+        esp_hal::riscv::asm::wfi();
+    }
+}
+
 #[main]
 async fn main(_spawner: Spawner) {
     let peripherals = Peripherals::take();