Merge pull request #35 from Neotron-Compute/extra-functions

Add a power_off, power_reboot, and compare-and-swap function.

Author: jonathanpallant

Cargo.toml

@@ -7,7 +7,7 @@ license = "GPL-3.0-or-later"
 name = "neotron-common-bios"
 readme = "README.md"
 repository = "https://github.com/neotron-compute/neotron-common-bios.git"
-version = "0.10.0"
+version = "0.11.0-alpha"
 
 # See more keys and their definitions at https://doc.rust-lang.org/cargo/reference/manifest.html
 

src/lib.rs

@@ -311,7 +311,7 @@ pub struct Api {
 	/// (if any), or from the top of Region 0 (although this reduces the maximum
 	/// application space available). The OS will prefer lower numbered regions
 	/// (other than Region 0), so faster memory should be listed first.
-	pub memory_get_region: extern "C" fn(region_index: u8) -> crate::FfiOption<types::MemoryRegion>,
+	pub memory_get_region: extern "C" fn(region_index: u8) -> crate::FfiOption<MemoryRegion>,
 
 	// ========================================================================
 	// Human Interface Device Support
@@ -598,6 +598,25 @@ pub struct Api {
 	/// On a microcontroller, this will wait for interrupts. Running in an
 	/// emulator, this will sleep the thread for a while.
 	pub power_idle: extern "C" fn(),
+	/// The OS will call this function to control power on this system.
+	///
+	/// This function will not return, because the system will be switched off
+	/// before it can return. In the event on an error, this function will hang
+	/// instead.
+	pub power_control: extern "C" fn(mode: PowerMode) -> !,
+
+	// ========================================================================
+	// Mutex functions
+	// ========================================================================
+	/// Performs a compare-and-swap on `value`.
+	///
+	/// * If `value == old_value`, sets `value = new_value` and returns `true`
+	/// * If `value != old_value`, returns `false`
+	pub compare_and_swap_bool: extern "C" fn(
+		value: &core::sync::atomic::AtomicBool,
+		old_value: bool,
+		new_value: bool,
+	) -> bool,
 }
 
 // ============================================================================

src/types.rs

@@ -105,6 +105,21 @@ pub struct MemoryRegion {
 	pub kind: MemoryKind,
 }
 
+/// The kinds of power control we can do.
+#[repr(C)]
+#[derive(Debug, Copy, Clone)]
+pub enum PowerMode {
+	/// Turn the system power off
+	Off,
+	/// Reboot the main processor
+	Reset,
+	/// Reboot the main processor, but tell it to enter a bootloader mode for
+	/// programming. Precisely what this will do will depend upon the BIOS. Some
+	/// BIOSes will not have a bootloader mode and this will do a regular
+	/// reboot.
+	Bootloader,
+}
+
 // ============================================================================
 // Impls
 // ============================================================================