Monotonic rewrite (#874)

* Rework timer_queue and monotonic architecture

Goals:
 * make Monotonic purely internal
 * make Monotonic purely tick passed, no fugit involved
 * create a wrapper struct in the user's code via a macro that then
   converts the "now" from the tick based monotonic to a fugit based
   timestamp

We need to proxy the delay functions of the timer queue anyway,
so we could simply perform the conversion in those proxy functions.

* Update cargo.lock

* Update readme of rtic-time

* CI: ESP32: Redact esp_image: Too volatile

* Fixup: Changelog double entry rebase mistake

---------

Co-authored-by: Henrik Tjäder <henrik@tjaders.com>

7 files changed, 686 insertions, 0 deletions

diff --git a/examples/stm32g030f6_periodic_prints/.cargo/config.toml b/examples/stm32g030f6_periodic_prints/.cargo/config.toml
new file mode 100644
index 0000000..15ddd2a
--- /dev/null
+++ b/examples/stm32g030f6_periodic_prints/.cargo/config.toml
@@ -0,0 +1,24 @@
+[target.'cfg(all(target_arch = "arm", target_os = "none"))']
+# TODO(2) replace `$CHIP` with your chip's name (see `probe-run --list-chips` output)
+runner = "probe-run --chip STM32G030F6Px"
+rustflags = [
+  "-C", "linker=flip-link",
+  "-C", "link-arg=-Tlink.x",
+  "-C", "link-arg=-Tdefmt.x",
+  # This is needed if your flash or ram addresses are not aligned to 0x10000 in memory.x
+  # See https://github.com/rust-embedded/cortex-m-quickstart/pull/95
+  "-C", "link-arg=--nmagic",
+]
+
+[build]
+# TODO(3) Adjust the compilation target.
+# (`thumbv6m-*` is compatible with all ARM Cortex-M chips but using the right
+# target improves performance)
+target = "thumbv6m-none-eabi"    # Cortex-M0 and Cortex-M0+
+# target = "thumbv7m-none-eabi"    # Cortex-M3
+# target = "thumbv7em-none-eabi"   # Cortex-M4 and Cortex-M7 (no FPU)
+# target = "thumbv7em-none-eabihf" # Cortex-M4F and Cortex-M7F (with FPU)
+
+[alias]
+rb = "run --bin"
+rrb = "run --release --bin"
diff --git a/examples/stm32g030f6_periodic_prints/.vscode/settings.json b/examples/stm32g030f6_periodic_prints/.vscode/settings.json
new file mode 100644
index 0000000..c684c24
--- /dev/null
+++ b/examples/stm32g030f6_periodic_prints/.vscode/settings.json
@@ -0,0 +1,9 @@
+{
+    // override the default setting (`cargo check --all-targets`) which produces the following error
+    // "can't find crate for `test`" when the default compilation target is a no_std target
+    // with these changes RA will call `cargo check --bins` on save
+    "rust-analyzer.checkOnSave.allTargets": false,
+    "rust-analyzer.checkOnSave.extraArgs": [
+        "--bins"
+    ]
+}
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new file mode 100644
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--- /dev/null
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new file mode 100644
index 0000000..d8d8e35
--- /dev/null
+++ b/examples/stm32g030f6_periodic_prints/Cargo.toml
@@ -0,0 +1,48 @@
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+
+[dependencies]
+cortex-m = { version = "0.7.7", features = ["critical-section-single-core"] }
+cortex-m-rt = "0.7.3"
+defmt = "0.3.4"
+defmt-rtt = "0.4.0"
+fugit = "0.3.7"
+panic-probe = { version = "0.3.1", features = ["print-defmt"] }
+
+stm32g0xx-hal = { version = "0.2.0", features = ["rt", "stm32g030"] }
+
+# cargo build/run
+[profile.dev]
+codegen-units = 1
+debug = 2
+debug-assertions = true # <-
+incremental = false
+opt-level = 3           # <-
+overflow-checks = true  # <-
+
+# cargo build/run --release
+[profile.release]
+codegen-units = 1
+debug = 2
+debug-assertions = false # <-
+incremental = false
+lto = 'fat'
+opt-level = 3            # <-
+overflow-checks = false  # <-
diff --git a/examples/stm32g030f6_periodic_prints/README.md b/examples/stm32g030f6_periodic_prints/README.md
new file mode 100644
index 0000000..e669378
--- /dev/null
+++ b/examples/stm32g030f6_periodic_prints/README.md
@@ -0,0 +1,31 @@
+# `stm32g030f6_periodic_prints`
+
+An RTIC periodic print example intended for the stm32g030f6 chip.
+
+## Dependencies
+
+#### 1. `flip-link`:
+
+```console
+$ cargo install flip-link
+```
+
+#### 2. `probe-rs`:
+
+``` console
+$ # make sure to install v0.2.0 or later
+$ cargo install probe-rs --features cli
+```
+
+
+## Run
+
+The stm32g030f6 chip needs to be connected to the computer via an SWD probe, like a [J-Link EDU Mini].
+
+Then, run:
+
+```
+cargo run --release
+```
+
+[J-Link EDU Mini]: https://www.segger.com/products/debug-probes/j-link/models/j-link-edu-mini/
diff --git a/examples/stm32g030f6_periodic_prints/memory.x b/examples/stm32g030f6_periodic_prints/memory.x
new file mode 100644
index 0000000..3f89120
--- /dev/null
+++ b/examples/stm32g030f6_periodic_prints/memory.x
@@ -0,0 +1,6 @@
+/* Linker script for the STM32G030F6 */
+MEMORY
+{
+  FLASH : ORIGIN = 0x08000000, LENGTH = 32K
+  RAM : ORIGIN = 0x20000000, LENGTH = 8K
+}
diff --git a/examples/stm32g030f6_periodic_prints/src/main.rs b/examples/stm32g030f6_periodic_prints/src/main.rs
new file mode 100644
index 0000000..00fa802
--- /dev/null
+++ b/examples/stm32g030f6_periodic_prints/src/main.rs
@@ -0,0 +1,57 @@
+#![deny(unsafe_code)]
+#![deny(warnings)]
+#![no_main]
+#![no_std]
+
+use defmt_rtt as _; // global logger
+
+pub use stm32g0xx_hal as hal; // memory layout
+
+use panic_probe as _;
+
+// same panicking *behavior* as `panic-probe` but doesn't print a panic message
+// this prevents the panic message being printed *twice* when `defmt::panic` is invoked
+#[defmt::panic_handler]
+fn panic() -> ! {
+    cortex_m::asm::udf()
+}
+
+use rtic_monotonics::stm32::prelude::*;
+stm32_tim3_monotonic!(Mono, 1_000_000);
+
+#[rtic::app(device = hal::stm32, peripherals = true, dispatchers = [USART1, USART2])]
+mod app {
+    use super::*;
+
+    #[local]
+    struct LocalResources {}
+
+    #[shared]
+    struct SharedResources {}
+
+    #[init]
+    fn init(ctx: init::Context) -> (SharedResources, LocalResources) {
+        // enable dma clock during sleep, otherwise defmt doesn't work
+        ctx.device.RCC.ahbenr.modify(|_, w| w.dmaen().set_bit());
+
+        defmt::println!("TIM Monotonic blinker example!");
+
+        // Start the monotonic
+        Mono::start(16_000_000);
+
+        print_messages::spawn().unwrap();
+
+        (SharedResources {}, LocalResources {})
+    }
+
+    #[task(priority = 2)]
+    async fn print_messages(_cx: print_messages::Context) {
+        let mut next_update = <Mono as Monotonic>::Instant::from_ticks(0u64);
+
+        loop {
+            defmt::println!("Time: {} ticks", Mono::now().ticks());
+            next_update += 1000u64.millis();
+            Mono::delay_until(next_update).await;
+        }
+    }
+}