From 305dc9f4d364e57da7caf96826d0bddae78fdb2e Mon Sep 17 00:00:00 2001
From: Per Lindgren <per.lindgren@ltu.se>
Date: Thu, 10 Jan 2019 00:20:49 +0100
Subject: [PATCH] bare8
---
examples/bare8.rs | 287 +++++++++++++++++++++++++++++++++++++++++++++
examples/bare9.rs | 289 ++++++++++++++++++++++++++++++++++++++++++++++
2 files changed, 576 insertions(+)
create mode 100644 examples/bare8.rs
create mode 100644 examples/bare9.rs
diff --git a/examples/bare8.rs b/examples/bare8.rs
new file mode 100644
index 0000000..8d5f156
--- /dev/null
+++ b/examples/bare8.rs
@@ -0,0 +1,287 @@
+// #![deny(unsafe_code)]
+// #![deny(warnings)]
+#![no_main]
+#![no_std]
+
+extern crate panic_halt;
+
+use cortex_m::iprintln;
+use nb::block;
+
+extern crate stm32f4xx_hal as hal;
+use crate::hal::prelude::*;
+use crate::hal::serial::{config::Config, Rx, Serial, Tx};
+use hal::stm32::{ITM, USART2};
+
+// use crate::hal::stm32::Interrupt::EXTI0;
+use rtfm::app;
+// use hal::stm32::Interrupt::EXTI0;
+
+#[app(device = hal::stm32)]
+// #[app(device = stm32f4xx_hal::stm32)]
+
+const APP: () = {
+ // Late resources
+ static mut TX: Tx<USART2> = ();
+ static mut RX: Rx<USART2> = ();
+ static mut ITM: ITM = ();
+
+ // init runs in an interrupt free section
+ #[init]
+ fn init() {
+ let stim = &mut core.ITM.stim[0];
+ iprintln!(stim, "start");
+
+ let rcc = device.RCC.constrain();
+
+ // 16 MHz (default, all clocks)
+ let clocks = rcc.cfgr.freeze();
+
+ let gpioa = device.GPIOA.split();
+
+ let tx = gpioa.pa2.into_alternate_af7();
+ let rx = gpioa.pa3.into_alternate_af7(); // try comment out
+
+ let serial = Serial::usart2(
+ device.USART2,
+ (tx, rx),
+ Config::default().baudrate(115_200.bps()),
+ clocks,
+ )
+ .unwrap();
+
+ // Separate out the sender and receiver of the serial port
+ let (tx, rx) = serial.split();
+
+ // Late resources
+ TX = tx;
+ RX = rx;
+ ITM = core.ITM;
+ }
+
+ // idle may be interrupted by other interrupt/tasks in the system
+ #[idle(resources = [RX, TX, ITM])]
+ fn idle() -> ! {
+ let rx = resources.RX;
+ let tx = resources.TX;
+ let stim = &mut resources.ITM.stim[0];
+
+ loop {
+ match block!(rx.read()) {
+ Ok(byte) => {
+ iprintln!(stim, "Ok {:?}", byte);
+ let _ = tx.write(byte);
+ }
+ Err(err) => {
+ iprintln!(stim, "Error {:?}", err);
+ }
+ }
+ }
+ }
+};
+
+// extern crate cortex_m_rtfm as rtfm;
+// extern crate f4;
+// extern crate heapless;
+
+// #[macro_use]
+// extern crate cortex_m_debug;
+
+// use f4::prelude::*;
+// use f4::Serial;
+// use f4::time::Hertz;
+// use heapless::Vec;
+// use rtfm::{app, Resource, Threshold};
+
+// // CONFIGURATION
+// const BAUD_RATE: Hertz = Hertz(115_200);
+
+// // RTFM FRAMEWORK
+// app! {
+// device: f4::stm32f40x,
+
+// resources: {
+// static VECTOR: Vec<u8, [u8; 4]> = Vec::new();
+// },
+
+// tasks: {
+// USART2: {
+// path: rx,
+// priority: 2,
+// resources: [VECTOR, USART2],
+// },
+// EXTI1: {
+// path: trace,
+// priority: 1,
+// resources: [VECTOR],
+// }
+// },
+// }
+
+// // `rx` task trigger on arrival of a USART2 interrupt
+// fn rx(t: &mut Threshold, r: USART2::Resources) {
+// let serial = Serial(&**r.USART2);
+
+// // we don't need to block waiting for data to arrive
+// // (as we were triggered) by the data arrival (or error)
+// match serial.read() {
+// Ok(byte) => {
+// // received byte correct
+// r.VECTOR.claim_mut(t, |vector, _| {
+// // critical section for the shared vector
+// let _ = vector.push(byte);
+// // here you could put your error handling for vector full
+// });
+// let _ = serial.write(byte);
+// }
+// Err(err) => {
+// // some transmission error
+// ipln!("Error {:?}", err);
+// r.USART2.dr.read(); // clear the error by reading the data register
+// }
+// }
+
+// // trigger the `trace` task
+// rtfm::set_pending(f4::stm32f40x::Interrupt::EXTI1);
+// }
+
+// // `trace` task triggered by the hight priority `rx` task
+// // a low priority task for the background processing (like tracing)
+// fn trace(t: &mut Threshold, r: EXTI1::Resources) {
+// let mut b = [0; 4]; // local buffer
+// let mut l = 0; // length of the received vector
+
+// r.VECTOR.claim(t, |vector, _| {
+// // critical section for the shared vector
+// // here the task `rx` will be blocked from executing
+// l = vector.len();
+// b[..l].copy_from_slice(&***vector); // efficent copy vector to the local buffer
+// });
+// // since we do the actual tracing (relatively slow)
+// // OUTSIDE the claim (critical section), there will be no
+// // additional blocking of `rx`
+// ipln!("Vec {:?}", &b[..l]);
+// }
+
+// // Here we see the typical use of init INITIALIZING the system
+// fn init(p: init::Peripherals, _r: init::Resources) {
+// ipln!("init");
+// let serial = Serial(p.USART2);
+
+// serial.init(BAUD_RATE.invert(), None, p.GPIOA, p.RCC);
+// // in effect telling the USART2 to trigger the `rx` task/interrupt
+// serial.listen(f4::serial::Event::Rxne);
+// }
+
+// // We will spend all time sleeping (unless we have work to do)
+// // reactive programming in RTFM ftw!!!
+// fn idle() -> ! {
+// // Sleep
+// loop {
+// rtfm::wfi();
+// }
+// }
+
+// // 1. compile and run the project at 16MHz
+// // make sure its running (not paused)
+// // start a terminal program, e.g., `moserial`
+// // connect to the port
+// //
+// // Device /dev/ttyACM0
+// // Baude Rate 115200
+// // Data Bits 8
+// // Stop Bits 1
+// // Parity None
+// // Handshake None
+// //
+// // (this is also known in short as 15200 8N1)
+// //
+// // you should now be able to send data and recive an echo from the MCU
+// //
+// // try sending: "abcd" as a single sequence (set the option No end in moserial)
+// // (don't send the quation marks, just abcd)
+// //
+// // what did you receive, and what was the output of the ITM trace
+// // ** your answer here **
+// //
+// // did you experience any over-run errors?
+// // ** your answer here **
+// //
+// // what is the key problem and its solution (try to follow the commented code)
+// // ** your answer here **
+// //
+// // commit your answers (bare8_1)
+// //
+// // 2. now catch the case when we are trying to write to a full vector/buffer
+// // and write a suiteble error message
+// //
+// // commit your answers (bare8_2)
+// //
+// // as a side note....
+// //
+// // The concurrency model behind RTFM offers
+// // 1. Race-free resource access
+// //
+// // 2. Deadlock-free exection
+// //
+// // 3. Shared execution stack (no pre-allocated stack regions)
+// //
+// // 4. Bound priority inversion
+// //
+// // 5. Theoretical underpinning ->
+// // + proofs of soundness
+// // + schedulability analysis
+// // + response time analysis
+// // + stack memory analysis
+// // + ... leverages on 25 years of reseach in the real-time community
+// // based on the seminal work of Baker in the early 1990s
+// // (known as the Stack Resource Policy, SRP)
+// //
+// // Our implementation in Rust offers
+// // 1. compile check and analysis of tasks and resources
+// // + the API implementation together with the Rust compiler will ensure that
+// // both RTFM (SRP) soundness and the Rust memory model invariants
+// // are upheld (under all circumpstances).
+// //
+// // 2. arguably the worlds fastest real time scheduler *
+// // + task invocation 0-cycle OH on top of HW interrupt handling
+// // + 2 cycle OH for locking a shared resource (on claim entry)
+// // + 1 cycle OH for releasineg a shared resoure (on claim exit)
+// //
+// // 3. arguably the worlds most memory efficient scheduler *
+// // + 1 byte stack memory OH for each (nested) claim
+// // (no additional book-keeping during run-time)
+// //
+// // * applies to static task/resource models with single core
+// // pre-emptive, static priority scheduling
+// //
+// // in comparison "real-time" schedulers for threaded models like FreeRTOS
+// // - CPU and memory OH magnitudes larger (100s of cycles/kilobytes of memory)
+// // - ... and what's worse OH is typically unbound (no proofs of worst case)
+// // - potential race conditions (up to the user to verify)
+// // - potential dead-locks (up to the implementation)
+// // - potential unbound priority inversion (up to the implementation)
+// //
+// // Rust RTFM (currently) target ONLY STATIC SYSTEMS, there is no notion
+// // of dynamically creating new executions contexts/threads
+// // so a direct comparison is not completely fair.
+// //
+// // On the other hand, embedded applications are typically static by nature
+// // so a STATIC model is to that end better suitable.
+// //
+// // RTFM is reactive by nature, a task execute to end, triggered
+// // by an internal or external event, (where an interrupt is an external event
+// // from the environment, like a HW peripheral such as the USART2).
+// //
+// // Threads on the other hand are concurrent and infinte by nature and
+// // actively blocking/yeilding awaiting stimuli. Hence reactivity needs to be CODED.
+// // This leads to an anomaly, the underlying HW is reactive (interrupts),
+// // requiring an interrupt handler, that creates a signal to the scheduler.
+// //
+// // The scheduler then needs to keep track of all threads and at some point choose
+// // to dispatch the awaiting thread. So reactivity is bottlenecked to the point
+// // of scheduling by que management, context switching and other additional
+// // book keeping.
+// //
+// // In essence, the thread scheduler tries to re-establish the reactivity that
+// // were there (interrupts), a battle that cannot be won...
diff --git a/examples/bare9.rs b/examples/bare9.rs
new file mode 100644
index 0000000..bc6abcc
--- /dev/null
+++ b/examples/bare9.rs
@@ -0,0 +1,289 @@
+// #![deny(unsafe_code)]
+// #![deny(warnings)]
+#![no_main]
+#![no_std]
+
+extern crate panic_halt;
+
+use cortex_m::iprintln;
+use nb::block;
+
+extern crate stm32f4xx_hal as hal;
+use crate::hal::prelude::*;
+use crate::hal::serial::{config::Config, Rx, Serial, Tx};
+use hal::stm32::{ITM, USART2};
+
+// use crate::hal::stm32::Interrupt::EXTI0;
+use rtfm::app;
+// use hal::stm32::Interrupt::EXTI0;
+
+#[app(device = hal::stm32)]
+// #[app(device = stm32f4xx_hal::stm32)]
+
+const APP: () = {
+ // Late resources
+ static mut TX: Tx<USART2> = ();
+ static mut RX: Rx<USART2> = ();
+ static mut ITM: ITM = ();
+
+ // init runs in an interrupt free section
+ #[init]
+ fn init() {
+ let stim = &mut core.ITM.stim[0];
+ iprintln!(stim, "start");
+
+ let rcc = device.RCC.constrain();
+
+ // 16 MHz (default, all clocks)
+ let clocks = rcc.cfgr.freeze();
+
+ let gpioa = device.GPIOA.split();
+
+ let tx = gpioa.pa2.into_alternate_af7();
+ let rx = gpioa.pa3.into_alternate_af7(); // try comment out
+
+ let serial = Serial::usart2(
+ device.USART2,
+ (tx, rx),
+ Config::default().baudrate(115_200.bps()),
+ clocks,
+ )
+ .unwrap();
+
+ // Separate out the sender and receiver of the serial port
+ let (tx, rx) = serial.split();
+
+ // Late resources
+ TX = tx;
+ RX = rx;
+ ITM = core.ITM;
+ }
+
+ // idle may be interrupted by other interrupt/tasks in the system
+ #[idle(resources = [RX, TX, ITM])]
+ fn idle() -> ! {
+ let rx = resources.RX;
+ let tx = resources.TX;
+ let stim = &mut resources.ITM.stim[0];
+
+ loop {
+ match block!(rx.read()) {
+ Ok(byte) => {
+ iprintln!(stim, "Ok {:?}", byte);
+ let _ = tx.write(byte);
+ }
+ Err(err) => {
+ iprintln!(stim, "Error {:?}", err);
+ }
+ }
+ }
+ }
+ #[interrupt]
+ fn EXTI0() {}
+};
+
+// extern crate cortex_m_rtfm as rtfm;
+// extern crate f4;
+// extern crate heapless;
+
+// #[macro_use]
+// extern crate cortex_m_debug;
+
+// use f4::prelude::*;
+// use f4::Serial;
+// use f4::time::Hertz;
+// use heapless::Vec;
+// use rtfm::{app, Resource, Threshold};
+
+// // CONFIGURATION
+// const BAUD_RATE: Hertz = Hertz(115_200);
+
+// // RTFM FRAMEWORK
+// app! {
+// device: f4::stm32f40x,
+
+// resources: {
+// static VECTOR: Vec<u8, [u8; 4]> = Vec::new();
+// },
+
+// tasks: {
+// USART2: {
+// path: rx,
+// priority: 2,
+// resources: [VECTOR, USART2],
+// },
+// EXTI1: {
+// path: trace,
+// priority: 1,
+// resources: [VECTOR],
+// }
+// },
+// }
+
+// // `rx` task trigger on arrival of a USART2 interrupt
+// fn rx(t: &mut Threshold, r: USART2::Resources) {
+// let serial = Serial(&**r.USART2);
+
+// // we don't need to block waiting for data to arrive
+// // (as we were triggered) by the data arrival (or error)
+// match serial.read() {
+// Ok(byte) => {
+// // received byte correct
+// r.VECTOR.claim_mut(t, |vector, _| {
+// // critical section for the shared vector
+// let _ = vector.push(byte);
+// // here you could put your error handling for vector full
+// });
+// let _ = serial.write(byte);
+// }
+// Err(err) => {
+// // some transmission error
+// ipln!("Error {:?}", err);
+// r.USART2.dr.read(); // clear the error by reading the data register
+// }
+// }
+
+// // trigger the `trace` task
+// rtfm::set_pending(f4::stm32f40x::Interrupt::EXTI1);
+// }
+
+// // `trace` task triggered by the hight priority `rx` task
+// // a low priority task for the background processing (like tracing)
+// fn trace(t: &mut Threshold, r: EXTI1::Resources) {
+// let mut b = [0; 4]; // local buffer
+// let mut l = 0; // length of the received vector
+
+// r.VECTOR.claim(t, |vector, _| {
+// // critical section for the shared vector
+// // here the task `rx` will be blocked from executing
+// l = vector.len();
+// b[..l].copy_from_slice(&***vector); // efficent copy vector to the local buffer
+// });
+// // since we do the actual tracing (relatively slow)
+// // OUTSIDE the claim (critical section), there will be no
+// // additional blocking of `rx`
+// ipln!("Vec {:?}", &b[..l]);
+// }
+
+// // Here we see the typical use of init INITIALIZING the system
+// fn init(p: init::Peripherals, _r: init::Resources) {
+// ipln!("init");
+// let serial = Serial(p.USART2);
+
+// serial.init(BAUD_RATE.invert(), None, p.GPIOA, p.RCC);
+// // in effect telling the USART2 to trigger the `rx` task/interrupt
+// serial.listen(f4::serial::Event::Rxne);
+// }
+
+// // We will spend all time sleeping (unless we have work to do)
+// // reactive programming in RTFM ftw!!!
+// fn idle() -> ! {
+// // Sleep
+// loop {
+// rtfm::wfi();
+// }
+// }
+
+// // 1. compile and run the project at 16MHz
+// // make sure its running (not paused)
+// // start a terminal program, e.g., `moserial`
+// // connect to the port
+// //
+// // Device /dev/ttyACM0
+// // Baude Rate 115200
+// // Data Bits 8
+// // Stop Bits 1
+// // Parity None
+// // Handshake None
+// //
+// // (this is also known in short as 15200 8N1)
+// //
+// // you should now be able to send data and recive an echo from the MCU
+// //
+// // try sending: "abcd" as a single sequence (set the option No end in moserial)
+// // (don't send the quation marks, just abcd)
+// //
+// // what did you receive, and what was the output of the ITM trace
+// // ** your answer here **
+// //
+// // did you experience any over-run errors?
+// // ** your answer here **
+// //
+// // what is the key problem and its solution (try to follow the commented code)
+// // ** your answer here **
+// //
+// // commit your answers (bare8_1)
+// //
+// // 2. now catch the case when we are trying to write to a full vector/buffer
+// // and write a suiteble error message
+// //
+// // commit your answers (bare8_2)
+// //
+// // as a side note....
+// //
+// // The concurrency model behind RTFM offers
+// // 1. Race-free resource access
+// //
+// // 2. Deadlock-free exection
+// //
+// // 3. Shared execution stack (no pre-allocated stack regions)
+// //
+// // 4. Bound priority inversion
+// //
+// // 5. Theoretical underpinning ->
+// // + proofs of soundness
+// // + schedulability analysis
+// // + response time analysis
+// // + stack memory analysis
+// // + ... leverages on 25 years of reseach in the real-time community
+// // based on the seminal work of Baker in the early 1990s
+// // (known as the Stack Resource Policy, SRP)
+// //
+// // Our implementation in Rust offers
+// // 1. compile check and analysis of tasks and resources
+// // + the API implementation together with the Rust compiler will ensure that
+// // both RTFM (SRP) soundness and the Rust memory model invariants
+// // are upheld (under all circumpstances).
+// //
+// // 2. arguably the worlds fastest real time scheduler *
+// // + task invocation 0-cycle OH on top of HW interrupt handling
+// // + 2 cycle OH for locking a shared resource (on claim entry)
+// // + 1 cycle OH for releasineg a shared resoure (on claim exit)
+// //
+// // 3. arguably the worlds most memory efficient scheduler *
+// // + 1 byte stack memory OH for each (nested) claim
+// // (no additional book-keeping during run-time)
+// //
+// // * applies to static task/resource models with single core
+// // pre-emptive, static priority scheduling
+// //
+// // in comparison "real-time" schedulers for threaded models like FreeRTOS
+// // - CPU and memory OH magnitudes larger (100s of cycles/kilobytes of memory)
+// // - ... and what's worse OH is typically unbound (no proofs of worst case)
+// // - potential race conditions (up to the user to verify)
+// // - potential dead-locks (up to the implementation)
+// // - potential unbound priority inversion (up to the implementation)
+// //
+// // Rust RTFM (currently) target ONLY STATIC SYSTEMS, there is no notion
+// // of dynamically creating new executions contexts/threads
+// // so a direct comparison is not completely fair.
+// //
+// // On the other hand, embedded applications are typically static by nature
+// // so a STATIC model is to that end better suitable.
+// //
+// // RTFM is reactive by nature, a task execute to end, triggered
+// // by an internal or external event, (where an interrupt is an external event
+// // from the environment, like a HW peripheral such as the USART2).
+// //
+// // Threads on the other hand are concurrent and infinte by nature and
+// // actively blocking/yeilding awaiting stimuli. Hence reactivity needs to be CODED.
+// // This leads to an anomaly, the underlying HW is reactive (interrupts),
+// // requiring an interrupt handler, that creates a signal to the scheduler.
+// //
+// // The scheduler then needs to keep track of all threads and at some point choose
+// // to dispatch the awaiting thread. So reactivity is bottlenecked to the point
+// // of scheduling by que management, context switching and other additional
+// // book keeping.
+// //
+// // In essence, the thread scheduler tries to re-establish the reactivity that
+// // were there (interrupts), a battle that cannot be won...
--
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