From d13d893ff2e7190ac8f9c2187e487a7abe45b43a Mon Sep 17 00:00:00 2001
From: Dario Nieuwenhuis <dirbaio@dirbaio.net>
Date: Tue, 31 May 2022 23:52:27 +0200
Subject: [PATCH] boot/stm32: autodetect thumbv6, remove cargo feature.

---
 embassy-boot/stm32/Cargo.toml    | 1 -
 embassy-boot/stm32/build.rs      | 5 +++++
 embassy-boot/stm32/src/lib.rs    | 2 +-
 examples/boot/stm32l0/Cargo.toml | 2 +-
 examples/boot/stm32l0/README.md  | 2 +-
 5 files changed, 8 insertions(+), 4 deletions(-)

diff --git a/embassy-boot/stm32/Cargo.toml b/embassy-boot/stm32/Cargo.toml
index 78339b0a..a31717ff 100644
--- a/embassy-boot/stm32/Cargo.toml
+++ b/embassy-boot/stm32/Cargo.toml
@@ -27,7 +27,6 @@ defmt = [
     "embassy-stm32/defmt",
 ]
 debug = ["defmt-rtt"]
-thumbv6 = []
 
 [profile.dev]
 debug = 2
diff --git a/embassy-boot/stm32/build.rs b/embassy-boot/stm32/build.rs
index fd605991..3997702f 100644
--- a/embassy-boot/stm32/build.rs
+++ b/embassy-boot/stm32/build.rs
@@ -24,4 +24,9 @@ fn main() {
     if env::var("CARGO_FEATURE_DEFMT").is_ok() {
         println!("cargo:rustc-link-arg-bins=-Tdefmt.x");
     }
+
+    let target = env::var("TARGET").unwrap();
+    if target.starts_with("thumbv6m-") {
+        println!("cargo:rustc-cfg=armv6m");
+    }
 }
diff --git a/embassy-boot/stm32/src/lib.rs b/embassy-boot/stm32/src/lib.rs
index 48512534..8c6e6550 100644
--- a/embassy-boot/stm32/src/lib.rs
+++ b/embassy-boot/stm32/src/lib.rs
@@ -76,7 +76,7 @@ impl<const PAGE_SIZE: usize> BootLoader<PAGE_SIZE> {
         trace!("Loading app at 0x{:x}", start);
         #[allow(unused_mut)]
         let mut p = cortex_m::Peripherals::steal();
-        #[cfg(not(feature = "thumbv6"))]
+        #[cfg(not(armv6m))]
         p.SCB.invalidate_icache();
         p.SCB.vtor.write(start as u32);
 
diff --git a/examples/boot/stm32l0/Cargo.toml b/examples/boot/stm32l0/Cargo.toml
index 13ca8436..a9e03155 100644
--- a/examples/boot/stm32l0/Cargo.toml
+++ b/examples/boot/stm32l0/Cargo.toml
@@ -7,7 +7,7 @@ version = "0.1.0"
 [dependencies]
 embassy = { version = "0.1.0", path = "../../../embassy", features = ["nightly"] }
 embassy-stm32 = { version = "0.1.0", path = "../../../embassy-stm32", features = ["unstable-traits", "nightly", "stm32l072cz", "time-driver-any", "exti", "memory-x"]  }
-embassy-boot-stm32 = { version = "0.1.0", path = "../../../embassy-boot/stm32", features = ["thumbv6"] }
+embassy-boot-stm32 = { version = "0.1.0", path = "../../../embassy-boot/stm32" }
 embassy-embedded-hal = { version = "0.1.0", path = "../../../embassy-embedded-hal" }
 
 defmt = { version = "0.3", optional = true }
diff --git a/examples/boot/stm32l0/README.md b/examples/boot/stm32l0/README.md
index b498fdc2..a0e8021f 100644
--- a/examples/boot/stm32l0/README.md
+++ b/examples/boot/stm32l0/README.md
@@ -15,7 +15,7 @@ application.
 
 ```
 # Flash bootloader
-cargo flash --manifest-path ../../../embassy-boot/stm32/Cargo.toml --release --features embassy-stm32/stm32l072cz,thumbv6 --chip STM32L072CZTx
+cargo flash --manifest-path ../../../embassy-boot/stm32/Cargo.toml --release --features embassy-stm32/stm32l072cz --chip STM32L072CZTx
 # Build 'b'
 cargo build --release --bin b
 # Generate binary for 'b'