Re-arranged into three binaries.

Each binary gets a unique linker argument in build.rs.

Author: jonathanpallant

.cargo/config

@@ -1,5 +1,2 @@
-[target.thumbv7em-none-eabihf]
-runner = 'arm-none-eabi-gdb --command=gdb.cfg -w'
-
 [build]
-target = "thumbv7em-none-eabihf"
+target = "thumbv6m-none-eabi"

.vscode/settings.json

@@ -0,0 +1,4 @@
+{
+    "rust-analyzer.checkOnSave.allTargets": false,
+    "rust-analyzer.cargo.target": "thumbv6m-none-eabi"
+}

Cargo.toml

@@ -1,5 +1,5 @@
 [package]
-name = "neotron_os"
+name = "neotron-os"
 version = "0.1.0"
 authors = ["Jonathan 'theJPster' Pallant <github@thejpster.org.uk>"]
 edition = "2018"
@@ -9,7 +9,17 @@ readme = "README.md"
 repository = "https://github.com/neotron-compute/Neotron-OS"
 
 [[bin]]
-name = "neotron_os"
+name = "flash1002"
+test = false
+bench = false
+
+[[bin]]
+name = "flash0802"
+test = false
+bench = false
+
+[[bin]]
+name = "flash0002"
 test = false
 bench = false
 

README.md

@@ -19,43 +19,34 @@ This OS is a work in progress. We intend to support:
 
 ## Build instructions
 
-Your board will need an appropriate Neotron BIOS installed, and you need to
-have OpenOCD (or other programming tool) running for your particular board.
-You may also need to set the linker arguments so you link the binary to suit
-the memory available on your system.
+Your board will need an appropriate Neotron BIOS installed, and you need to have
+OpenOCD or some other programming tool running for your particular board. See
+your BIOS instructions for more details.
 
-### Build Instructions for the Neotron Pico (and other systems with Flash at `0x1000_0000`)
+We compile one version of Neotron OS, but we link it three times to produce
+three binaries:
 
-```
-$ git clone https://github.com/neotron-compute/Neotron-OS.git
-$ cd Neotron-OS
-$ git submodule update --init
-$ RUSTFLAGS="-C link-arg=-Tneotron-flash-1000.ld" cargo build --release --target=thumbv6m-none-eabi
-```
-
-### Build Instructions for the STM32 (and other systems with Flash at `0x0800_0000`)
+* `flash0002` - is linked to run from address `0x0002_0000`
+* `flash1002` - is linked to run from address `0x1002_0000`
+* `flash0802` - is linked to run from address `0x0802_0000`
 
 ```
 $ git clone https://github.com/neotron-compute/Neotron-OS.git
 $ cd Neotron-OS
 $ git submodule update --init
-$ RUSTFLAGS="-C link-arg=-Tneotron-flash-0800.ld" cargo build --release --target=thumbv6m-none-eabi
+$ cargo build --release
+$ ls ./target/thumbv6m-none-eabi/release/flash{10,08,00}02
+./target/thumbv6m-none-eabi/release/flash0002 ./target/thumbv6m-none-eabi/release/flash0802 ./target/thumbv6m-none-eabi/release/flash1002
 ```
 
-### Build Instructions for other systems (with Flash at `0x0000_0000`)
-
-```
-$ git clone https://github.com/neotron-compute/Neotron-OS.git
-$ cd Neotron-OS
-$ git submodule update --init
-$ RUSTFLAGS="-C link-arg=-Tneotron-flash-0000.ld" cargo run --release
-```
+Your BIOS should tell you which one you want and how to load it onto your system.
 
 ## Changelog
 
 ### Unreleased Changes ([Source](https://github.com/neotron-compute/Neotron-OS/tree/master))
 
 * Basic `println!` to the text buffer.
+* Re-arranged linker script setup
 
 ## Licence
 

build.rs

@@ -0,0 +1,5 @@
+fn main() {
+    println!("cargo:rustc-link-arg-bin=flash1002=-Tneotron-flash-1000.ld");
+    println!("cargo:rustc-link-arg-bin=flash0802=-Tneotron-flash-0800.ld");
+    println!("cargo:rustc-link-arg-bin=flash0002=-Tneotron-flash-0000.ld");
+}

src/bin/flash0002.rs

@@ -0,0 +1,17 @@
+//! Binary Neotron OS Image
+//!
+//! This is for Flash Addresses that start at `0x0002_0000`.
+//!
+//! Copyright (c) The Neotron Developers, 2022
+//!
+//! Licence: GPL v3 or higher (see ../LICENCE.md)
+
+#![no_std]
+#![no_main]
+
+/// This tells the BIOS how to start the OS. This must be the first four bytes
+/// of our portion of Flash.
+#[link_section = ".entry_point"]
+#[used]
+pub static ENTRY_POINT_ADDR: extern "C" fn(&'static neotron_common_bios::Api) -> ! =
+    neotron_os::main;

src/bin/flash0802.rs

@@ -0,0 +1,17 @@
+//! Binary Neotron OS Image
+//!
+//! This is for Flash Addresses that start at `0x0802_0000`.
+//!
+//! Copyright (c) The Neotron Developers, 2022
+//!
+//! Licence: GPL v3 or higher (see ../LICENCE.md)
+
+#![no_std]
+#![no_main]
+
+/// This tells the BIOS how to start the OS. This must be the first four bytes
+/// of our portion of Flash.
+#[link_section = ".entry_point"]
+#[used]
+pub static ENTRY_POINT_ADDR: extern "C" fn(&'static neotron_common_bios::Api) -> ! =
+    neotron_os::main;

src/bin/flash1002.rs

@@ -0,0 +1,17 @@
+//! Binary Neotron OS Image
+//!
+//! This is for Flash Addresses that start at `0x1002_0000`.
+//!
+//! Copyright (c) The Neotron Developers, 2022
+//!
+//! Licence: GPL v3 or higher (see ../LICENCE.md)
+
+#![no_std]
+#![no_main]
+
+/// This tells the BIOS how to start the OS. This must be the first four bytes
+/// of our portion of Flash.
+#[link_section = ".entry_point"]
+#[used]
+pub static ENTRY_POINT_ADDR: extern "C" fn(&'static neotron_common_bios::Api) -> ! =
+    neotron_os::main;

src/main.rs src/lib.rssrc/main.rs renamed to src/lib.rs

@@ -2,12 +2,11 @@
 //!
 //! This OS is intended to be loaded by a Neotron BIOS.
 //!
-//! Copyright (c) The Neotron Developers, 2020
+//! Copyright (c) The Neotron Developers, 2022
 //!
 //! Licence: GPL v3 or higher (see ../LICENCE.md)
 
 #![no_std]
-#![no_main]
 
 // Imports
 use core::fmt::Write;
@@ -18,12 +17,6 @@ use serde::{Deserialize, Serialize};
 // Global Variables
 // ===========================================================================
 
-/// This tells the BIOS how to start the OS. This must be the first four bytes
-/// of our portion of Flash.
-#[link_section = ".entry_point"]
-#[used]
-pub static ENTRY_POINT_ADDR: extern "C" fn(&'static bios::Api) -> ! = main;
-
 /// The OS version string
 const OS_VERSION: &str = concat!("Neotron OS, version ", env!("CARGO_PKG_VERSION"), "-2");
 
@@ -282,7 +275,7 @@ unsafe fn start_up_init() {
 
 /// This is the function the BIOS calls. This is because we store the address
 /// of this function in the ENTRY_POINT_ADDR variable.
-extern "C" fn main(api: &'static bios::Api) -> ! {
+pub extern "C" fn main(api: &'static bios::Api) -> ! {
     unsafe {
         start_up_init();
         API = Some(api);