10 files changed, 195 insertions, 24 deletions

diff --git a/.github/workflows/rust.yml b/.github/workflows/rust.yml
index 2035c96dc..118143daa 100644
--- a/.github/workflows/rust.yml
+++ b/.github/workflows/rust.yml
@@ -88,6 +88,8 @@ jobs:
             target: thumbv6m-none-eabi
           - package: examples/stm32wb55
             target: thumbv7em-none-eabihf
+          - package: examples/stm32f0
+            target: thumbv6m-none-eabi
 
     steps:
       - uses: actions/checkout@v2
diff --git a/embassy-stm32/src/bdma/mod.rs b/embassy-stm32/src/bdma/mod.rs
index 39e8bec3b..f57358f68 100644
--- a/embassy-stm32/src/bdma/mod.rs
+++ b/embassy-stm32/src/bdma/mod.rs
@@ -177,7 +177,7 @@ pub(crate) unsafe fn init() {
     }
     pac::peripherals! {
         (bdma, $peri:ident) => {
-            crate::peripherals::$peri::enable();
+            <crate::peripherals::$peri as RccPeripheral>::enable();
         };
     }
 }
diff --git a/embassy-stm32/src/rcc/mod.rs b/embassy-stm32/src/rcc/mod.rs
index b7b692f15..c02db58fe 100644
--- a/embassy-stm32/src/rcc/mod.rs
+++ b/embassy-stm32/src/rcc/mod.rs
@@ -123,4 +123,33 @@ crate::pac::peripheral_rcc!(
 
         impl RccPeripheral for peripherals::$inst {}
     };
+    ($inst:ident, $clk:ident, $enable:ident, $perien:ident) => {
+        impl sealed::RccPeripheral for peripherals::$inst {
+            fn frequency() -> crate::time::Hertz {
+                critical_section::with(|_| {
+                    unsafe {
+                        let freqs = get_freqs();
+                        freqs.$clk
+                    }
+                })
+            }
+            fn enable() {
+                critical_section::with(|_| {
+                    unsafe {
+                        crate::pac::RCC.$enable().modify(|w| w.$perien(true));
+                    }
+                })
+            }
+            fn disable() {
+                critical_section::with(|_| {
+                    unsafe {
+                        crate::pac::RCC.$enable().modify(|w| w.$perien(false));
+                    }
+                })
+            }
+            fn reset() {}
+        }
+
+        impl RccPeripheral for peripherals::$inst {}
+    };
 );
diff --git a/examples/stm32f0/.cargo/config.toml b/examples/stm32f0/.cargo/config.toml
new file mode 100644
index 000000000..7506fa91b
--- /dev/null
+++ b/examples/stm32f0/.cargo/config.toml
@@ -0,0 +1,10 @@
+[target.thumbv6m-none-eabi]
+runner = 'probe-run --chip STM32F030F4Px'
+rustflags = [
+  # LLD (shipped with the Rust toolchain) is used as the default linker
+  "-C", "link-arg=-Tlink.x",
+  "-C", "link-arg=-Tdefmt.x",
+]
+
+[build]
+target = "thumbv6m-none-eabi"
diff --git a/examples/stm32f0/Cargo.toml b/examples/stm32f0/Cargo.toml
new file mode 100644
index 000000000..cc2c3f2b7
--- /dev/null
+++ b/examples/stm32f0/Cargo.toml
@@ -0,0 +1,29 @@
+[package]
+name = "embassy-stm32f0-examples"
+version = "0.1.0"
+authors = ["Thales Fragoso <[email protected]>"]
+edition = "2018"
+resolver = "2"
+
+# See more keys and their definitions at https://doc.rust-lang.org/cargo/reference/manifest.html
+
+[dependencies]
+cortex-m = { version = "0.7.1", features = ["inline-asm"] }
+cortex-m-rt = "0.6.13"
+defmt = "0.2.0"
+defmt-rtt = "0.2.0"
+panic-probe = { version = "0.2.0" }
+rtt-target = { version = "0.3", features = ["cortex-m"] }
+embassy = { path = "../../embassy", features = ["defmt"] }
+embassy-stm32 = { path = "../../embassy-stm32", features = ["defmt", "stm32f030f4"] }
+
+[features]
+default = [
+    "defmt-default",
+]
+defmt-default = []
+defmt-trace = []
+defmt-debug = []
+defmt-info = []
+defmt-warn = []
+defmt-error = []
diff --git a/examples/stm32f0/build.rs b/examples/stm32f0/build.rs
new file mode 100644
index 000000000..d534cc3df
--- /dev/null
+++ b/examples/stm32f0/build.rs
@@ -0,0 +1,31 @@
+//! This build script copies the `memory.x` file from the crate root into
+//! a directory where the linker can always find it at build time.
+//! For many projects this is optional, as the linker always searches the
+//! project root directory -- wherever `Cargo.toml` is. However, if you
+//! are using a workspace or have a more complicated build setup, this
+//! build script becomes required. Additionally, by requesting that
+//! Cargo re-run the build script whenever `memory.x` is changed,
+//! updating `memory.x` ensures a rebuild of the application with the
+//! new memory settings.
+
+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");
+}
diff --git a/examples/stm32f0/memory.x b/examples/stm32f0/memory.x
new file mode 100644
index 000000000..3bddaed41
--- /dev/null
+++ b/examples/stm32f0/memory.x
@@ -0,0 +1,6 @@
+MEMORY
+{
+  FLASH : ORIGIN = 0x08000000, LENGTH = 16K
+  /* DTCM  */
+  RAM : ORIGIN = 0x20000000, LENGTH = 4K
+}
diff --git a/examples/stm32f0/src/bin/hello.rs b/examples/stm32f0/src/bin/hello.rs
new file mode 100644
index 000000000..a78b9892f
--- /dev/null
+++ b/examples/stm32f0/src/bin/hello.rs
@@ -0,0 +1,23 @@
+#![no_std]
+#![no_main]
+#![feature(min_type_alias_impl_trait)]
+#![feature(impl_trait_in_bindings)]
+#![feature(type_alias_impl_trait)]
+#![allow(incomplete_features)]
+
+use defmt::info;
+
+use embassy::executor::Spawner;
+use embassy::time::{Duration, Timer};
+use embassy_stm32::Peripherals;
+
+#[path = "../example_common.rs"]
+mod example_common;
+
+#[embassy::main]
+async fn main(_spawner: Spawner, _p: Peripherals) -> ! {
+    loop {
+        Timer::after(Duration::from_secs(1)).await;
+        info!("Hello");
+    }
+}
diff --git a/examples/stm32f0/src/example_common.rs b/examples/stm32f0/src/example_common.rs
new file mode 100644
index 000000000..54d633837
--- /dev/null
+++ b/examples/stm32f0/src/example_common.rs
@@ -0,0 +1,17 @@
+#![macro_use]
+
+use defmt_rtt as _; // global logger
+use panic_probe as _;
+
+pub use defmt::*;
+
+use core::sync::atomic::{AtomicUsize, Ordering};
+
+defmt::timestamp! {"{=u64}", {
+        static COUNT: AtomicUsize = AtomicUsize::new(0);
+        // NOTE(no-CAS) `timestamps` runs with interrupts disabled
+        let n = COUNT.load(Ordering::Relaxed);
+        COUNT.store(n + 1, Ordering::Relaxed);
+        n as u64
+    }
+}
diff --git a/stm32-metapac-gen/src/lib.rs b/stm32-metapac-gen/src/lib.rs
index 37254f6f0..a9ee88002 100644
--- a/stm32-metapac-gen/src/lib.rs
+++ b/stm32-metapac-gen/src/lib.rs
@@ -142,18 +142,17 @@ macro_rules! peripheral_count {{
 }
 
 fn make_dma_channel_counts(out: &mut String, data: &HashMap<String, u8>) {
-    write!(out,
-           "#[macro_export]
+    write!(
+        out,
+        "#[macro_export]
 macro_rules! dma_channels_count {{
-    ").unwrap();
+    "
+    )
+    .unwrap();
     for (name, count) in data {
-        write!(out,
-               "({}) => ({});\n",
-               name, count,
-        ).unwrap();
+        write!(out, "({}) => ({});\n", name, count,).unwrap();
     }
-    write!(out,
-           " }}\n").unwrap();
+    write!(out, " }}\n").unwrap();
 }
 
 fn make_table(out: &mut String, name: &str, data: &Vec<Vec<String>>) {
@@ -409,11 +408,25 @@ pub fn gen(options: Options) {
                     if let Some(clock_prefix) = clock_prefix {
                         // Workaround for clock registers being split on some chip families. Assume fields are
                         // named after peripheral and look for first field matching and use that register.
-                        let en = find_reg_for_field(&rcc, clock_prefix, &format!("{}EN", name));
-                        let rst = find_reg_for_field(&rcc, clock_prefix, &format!("{}RST", name));
+                        let mut en = find_reg_for_field(&rcc, clock_prefix, &format!("{}EN", name));
+                        let mut rst =
+                            find_reg_for_field(&rcc, clock_prefix, &format!("{}RST", name));
+
+                        if en.is_none() && name.ends_with("1") {
+                            en = find_reg_for_field(
+                                &rcc,
+                                clock_prefix,
+                                &format!("{}EN", &name[..name.len() - 1]),
+                            );
+                            rst = find_reg_for_field(
+                                &rcc,
+                                clock_prefix,
+                                &format!("{}RST", &name[..name.len() - 1]),
+                            );
+                        }
 
                         match (en, rst) {
-                            (Some((enable_reg, enable_field)), Some((reset_reg, reset_field))) => {
+                            (Some((enable_reg, enable_field)), reset_reg_field) => {
                                 let clock = if clock_prefix.is_empty() {
                                     let re = Regex::new("([A-Z]+\\d*).*").unwrap();
                                     if !re.is_match(enable_reg) {
@@ -436,22 +449,33 @@ pub fn gen(options: Options) {
                                 };
 
                                 if !name.starts_with("GPIO") {
-                                    peripheral_rcc_table.push(vec![
-                                        name.clone(),
-                                        clock,
-                                        enable_reg.to_ascii_lowercase(),
-                                        reset_reg.to_ascii_lowercase(),
-                                        format!("set_{}", enable_field.to_ascii_lowercase()),
-                                        format!("set_{}", reset_field.to_ascii_lowercase()),
-                                    ]);
+                                    let mut row = Vec::with_capacity(6);
+                                    row.push(name.clone());
+                                    row.push(clock);
+                                    row.push(enable_reg.to_ascii_lowercase());
+
+                                    if let Some((reset_reg, reset_field)) = reset_reg_field {
+                                        row.push(reset_reg.to_ascii_lowercase());
+                                        row.push(format!(
+                                            "set_{}",
+                                            enable_field.to_ascii_lowercase()
+                                        ));
+                                        row.push(format!(
+                                            "set_{}",
+                                            reset_field.to_ascii_lowercase()
+                                        ));
+                                    } else {
+                                        row.push(format!(
+                                            "set_{}",
+                                            enable_field.to_ascii_lowercase()
+                                        ));
+                                    }
+                                    peripheral_rcc_table.push(row);
                                 }
                             }
                             (None, Some(_)) => {
                                 print!("Unable to find enable register for {}", name)
                             }
-                            (Some(_), None) => {
-                                print!("Unable to find reset register for {}", name)
-                            }
                             (None, None) => {
                                 print!("Unable to find enable and reset register for {}", name)
                             }