Refactor tutorial 09
Andre Richter
4 years ago
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353cc4b6d5
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7e583dc923
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// SPDX-License-Identifier: MIT OR Apache-2.0
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//
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// Copyright (c) 2018-2020 Andre Richter <andre.o.richter@gmail.com>
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//! Architectural symmetric multiprocessing.
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use cortex_a::regs::*;
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//--------------------------------------------------------------------------------------------------
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// Public Code
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//--------------------------------------------------------------------------------------------------
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/// Return the executing core's id.
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#[inline(always)]
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pub fn core_id<T>() -> T
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where
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T: From<u8>,
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{
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const CORE_MASK: u64 = 0b11;
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T::from((MPIDR_EL1.get() & CORE_MASK) as u8)
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}
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// SPDX-License-Identifier: MIT OR Apache-2.0
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//
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// Copyright (c) 2018-2020 Andre Richter <andre.o.richter@gmail.com>
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//! Conditional exporting of processor architecture code.
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#[cfg(any(feature = "bsp_rpi3", feature = "bsp_rpi4"))]
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mod aarch64;
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#[cfg(any(feature = "bsp_rpi3", feature = "bsp_rpi4"))]
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pub use aarch64::*;
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// SPDX-License-Identifier: MIT OR Apache-2.0
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//
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// Copyright (c) 2018-2020 Andre Richter <andre.o.richter@gmail.com>
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//! Synchronization primitives.
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use crate::interface;
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use core::cell::UnsafeCell;
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//--------------------------------------------------------------------------------------------------
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// Arch-public
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//--------------------------------------------------------------------------------------------------
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/// A pseudo-lock for teaching purposes.
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///
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/// Used to introduce [interior mutability].
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///
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/// In contrast to a real Mutex implementation, does not protect against concurrent access to the
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/// contained data. This part is preserved for later lessons.
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///
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/// The lock will only be used as long as it is safe to do so, i.e. as long as the kernel is
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/// executing single-threaded, aka only running on a single core with interrupts disabled.
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///
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/// [interior mutability]: https://doc.rust-lang.org/std/cell/index.html
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pub struct NullLock<T: ?Sized> {
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data: UnsafeCell<T>,
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}
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unsafe impl<T: ?Sized + Send> Send for NullLock<T> {}
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unsafe impl<T: ?Sized + Send> Sync for NullLock<T> {}
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impl<T> NullLock<T> {
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/// Wraps `data` into a new `NullLock`.
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pub const fn new(data: T) -> NullLock<T> {
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NullLock {
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data: UnsafeCell::new(data),
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}
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}
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}
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//--------------------------------------------------------------------------------------------------
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// OS interface implementations
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//--------------------------------------------------------------------------------------------------
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impl<T> interface::sync::Mutex for &NullLock<T> {
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type Data = T;
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fn lock<R>(&mut self, f: impl FnOnce(&mut Self::Data) -> R) -> R {
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// In a real lock, there would be code encapsulating this line that ensures that this
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// mutable reference will ever only be given out once at a time.
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f(unsafe { &mut *self.data.get() })
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}
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}
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// SPDX-License-Identifier: MIT OR Apache-2.0
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//
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// Copyright (c) 2018-2020 Andre Richter <andre.o.richter@gmail.com>
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//! Top-level BSP file for the Raspberry Pi 3 and 4.
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pub mod console;
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pub mod cpu;
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pub mod driver;
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pub mod memory;
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//--------------------------------------------------------------------------------------------------
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// Global instances
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//--------------------------------------------------------------------------------------------------
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use super::device_driver;
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static GPIO: device_driver::GPIO =
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unsafe { device_driver::GPIO::new(memory::map::mmio::GPIO_BASE) };
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static PL011_UART: device_driver::PL011Uart =
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unsafe { device_driver::PL011Uart::new(memory::map::mmio::PL011_UART_BASE) };
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//--------------------------------------------------------------------------------------------------
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// Public Code
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//--------------------------------------------------------------------------------------------------
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/// Board identification.
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pub fn board_name() -> &'static str {
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#[cfg(feature = "bsp_rpi3")]
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{
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"Raspberry Pi 3"
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}
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#[cfg(feature = "bsp_rpi4")]
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{
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"Raspberry Pi 4"
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}
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}
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// SPDX-License-Identifier: MIT OR Apache-2.0
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//
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// Copyright (c) 2018-2020 Andre Richter <andre.o.richter@gmail.com>
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//! BSP console facilities.
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use super::{super::device_driver, memory::map};
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use crate::console;
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use core::fmt;
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//--------------------------------------------------------------------------------------------------
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// Public Code
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//--------------------------------------------------------------------------------------------------
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/// In case of a panic, the panic handler uses this function to take a last shot at printing
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/// something before the system is halted.
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///
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/// # Safety
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///
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/// - Use only for printing during a panic.
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pub unsafe fn panic_console_out() -> impl fmt::Write {
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let mut uart = device_driver::PanicUart::new(map::mmio::PL011_UART_BASE);
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uart.init();
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uart
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}
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/// Return a reference to the console.
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pub fn console() -> &'static impl console::interface::All {
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&super::PL011_UART
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}
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// SPDX-License-Identifier: MIT OR Apache-2.0
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//
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// Copyright (c) 2018-2020 Andre Richter <andre.o.richter@gmail.com>
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//! BSP Processor code.
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//--------------------------------------------------------------------------------------------------
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// Public Definitions
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//--------------------------------------------------------------------------------------------------
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/// Used by `arch` code to find the early boot core.
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pub const BOOT_CORE_ID: usize = 0;
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/// The early boot core's stack address.
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pub const BOOT_CORE_STACK_START: u64 = 0x80_000;
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// SPDX-License-Identifier: MIT OR Apache-2.0
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//
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// Copyright (c) 2018-2020 Andre Richter <andre.o.richter@gmail.com>
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//! BSP driver support.
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use crate::driver;
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//--------------------------------------------------------------------------------------------------
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// Public Definitions
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//--------------------------------------------------------------------------------------------------
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/// Device Driver Manager type.
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pub struct BSPDriverManager {
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device_drivers: [&'static (dyn DeviceDriver + Sync); 2],
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}
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//--------------------------------------------------------------------------------------------------
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// Global instances
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//--------------------------------------------------------------------------------------------------
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static BSP_DRIVER_MANAGER: BSPDriverManager = BSPDriverManager {
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device_drivers: [&super::GPIO, &super::PL011_UART],
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};
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//--------------------------------------------------------------------------------------------------
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// Public Code
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//--------------------------------------------------------------------------------------------------
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/// Return a reference to the driver manager.
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pub fn driver_manager() -> &'static impl driver::interface::DriverManager {
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&BSP_DRIVER_MANAGER
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}
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//------------------------------------------------------------------------------
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// OS Interface Code
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//------------------------------------------------------------------------------
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use driver::interface::DeviceDriver;
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impl driver::interface::DriverManager for BSPDriverManager {
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fn all_device_drivers(&self) -> &[&'static (dyn DeviceDriver + Sync)] {
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&self.device_drivers[..]
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}
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fn post_device_driver_init(&self) {
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// Configure PL011Uart's output pins.
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super::GPIO.map_pl011_uart();
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}
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}
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// SPDX-License-Identifier: MIT OR Apache-2.0
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//
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// Copyright (c) 2018-2020 Andre Richter <andre.o.richter@gmail.com>
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//! BSP Memory Management.
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//--------------------------------------------------------------------------------------------------
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// Public Definitions
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//--------------------------------------------------------------------------------------------------
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/// The board's memory map.
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#[rustfmt::skip]
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pub(super) mod map {
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pub const GPIO_OFFSET: usize = 0x0020_0000;
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pub const UART_OFFSET: usize = 0x0020_1000;
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/// Physical devices.
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#[cfg(feature = "bsp_rpi3")]
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pub mod mmio {
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use super::*;
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pub const BASE: usize = 0x3F00_0000;
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pub const GPIO_BASE: usize = BASE + GPIO_OFFSET;
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pub const PL011_UART_BASE: usize = BASE + UART_OFFSET;
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}
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/// Physical devices.
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#[cfg(feature = "bsp_rpi4")]
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pub mod mmio {
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use super::*;
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pub const BASE: usize = 0xFE00_0000;
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pub const GPIO_BASE: usize = BASE + GPIO_OFFSET;
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pub const PL011_UART_BASE: usize = BASE + UART_OFFSET;
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}
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}
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// SPDX-License-Identifier: MIT OR Apache-2.0
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//
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// Copyright (c) 2018-2020 Andre Richter <andre.o.richter@gmail.com>
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//! Board Support Package for the Raspberry Pi.
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mod memory_map;
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use super::driver;
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use crate::interface;
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use core::fmt;
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/// Used by `arch` code to find the early boot core.
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pub const BOOT_CORE_ID: u64 = 0;
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/// The early boot core's stack address.
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pub const BOOT_CORE_STACK_START: u64 = 0x80_000;
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//--------------------------------------------------------------------------------------------------
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// Global BSP driver instances
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//--------------------------------------------------------------------------------------------------
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static GPIO: driver::GPIO = unsafe { driver::GPIO::new(memory_map::mmio::GPIO_BASE) };
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static PL011_UART: driver::PL011Uart =
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unsafe { driver::PL011Uart::new(memory_map::mmio::PL011_UART_BASE) };
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//--------------------------------------------------------------------------------------------------
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// Implementation of the kernel's BSP calls
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//--------------------------------------------------------------------------------------------------
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/// Board identification.
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pub fn board_name() -> &'static str {
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#[cfg(feature = "bsp_rpi3")]
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{
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"Raspberry Pi 3"
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}
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#[cfg(feature = "bsp_rpi4")]
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{
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"Raspberry Pi 4"
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}
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}
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/// Return a reference to a `console::All` implementation.
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pub fn console() -> &'static impl interface::console::All {
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&PL011_UART
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}
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/// In case of a panic, the panic handler uses this function to take a last shot at printing
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/// something before the system is halted.
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///
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/// # Safety
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///
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/// - Use only for printing during a panic.
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pub unsafe fn panic_console_out() -> impl fmt::Write {
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let uart = driver::PanicUart::new(memory_map::mmio::PL011_UART_BASE);
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uart.init();
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uart
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}
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/// Return an array of references to all `DeviceDriver` compatible `BSP` drivers.
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///
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/// # Safety
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///
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/// The order of devices is the order in which `DeviceDriver::init()` is called.
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pub fn device_drivers() -> [&'static dyn interface::driver::DeviceDriver; 2] {
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[&GPIO, &PL011_UART]
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}
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/// BSP initialization code that runs after driver init.
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pub fn post_driver_init() {
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// Configure PL011Uart's output pins.
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GPIO.map_pl011_uart();
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}
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// SPDX-License-Identifier: MIT OR Apache-2.0
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//
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// Copyright (c) 2018-2020 Andre Richter <andre.o.richter@gmail.com>
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//! The board's memory map.
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/// Physical devices.
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#[rustfmt::skip]
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pub mod mmio {
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#[cfg(feature = "bsp_rpi3")]
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pub const BASE: usize = 0x3F00_0000;
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#[cfg(feature = "bsp_rpi4")]
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pub const BASE: usize = 0xFE00_0000;
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pub const GPIO_BASE: usize = BASE + 0x0020_0000;
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pub const PL011_UART_BASE: usize = BASE + 0x0020_1000;
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}
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// SPDX-License-Identifier: MIT OR Apache-2.0
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//
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// Copyright (c) 2018-2020 Andre Richter <andre.o.richter@gmail.com>
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//! System console.
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//--------------------------------------------------------------------------------------------------
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// Public Definitions
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//--------------------------------------------------------------------------------------------------
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/// Console interfaces.
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pub mod interface {
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use core::fmt;
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/// Console write functions.
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pub trait Write {
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/// Write a single character.
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fn write_char(&self, c: char);
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/// Write a Rust format string.
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fn write_fmt(&self, args: fmt::Arguments) -> fmt::Result;
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/// Block execution until the last character has been physically put on the TX wire
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/// (draining TX buffers/FIFOs, if any).
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fn flush(&self);
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}
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/// Console read functions.
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pub trait Read {
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/// Read a single character.
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fn read_char(&self) -> char {
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' '
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}
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/// Clear RX buffers, if any.
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fn clear(&self);
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}
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/// Console statistics.
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pub trait Statistics {
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/// Return the number of characters written.
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fn chars_written(&self) -> usize {
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0
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}
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/// Return the number of characters read.
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fn chars_read(&self) -> usize {
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0
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}
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}
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/// Trait alias for a full-fledged console.
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pub trait All = Write + Read + Statistics;
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}
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// SPDX-License-Identifier: MIT OR Apache-2.0
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//
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// Copyright (c) 2020 Andre Richter <andre.o.richter@gmail.com>
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//! Processor code.
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#[cfg(target_arch = "aarch64")]
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#[path = "_arch/aarch64/cpu.rs"]
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mod arch_cpu;
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pub use arch_cpu::*;
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pub mod smp;
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// SPDX-License-Identifier: MIT OR Apache-2.0
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//
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// Copyright (c) 2018-2020 Andre Richter <andre.o.richter@gmail.com>
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//! Symmetric multiprocessing.
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#[cfg(target_arch = "aarch64")]
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#[path = "../_arch/aarch64/cpu/smp.rs"]
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mod arch_cpu_smp;
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pub use arch_cpu_smp::*;
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// SPDX-License-Identifier: MIT OR Apache-2.0
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//
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// Copyright (c) 2018-2020 Andre Richter <andre.o.richter@gmail.com>
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//! Driver support.
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//--------------------------------------------------------------------------------------------------
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// Public Definitions
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//--------------------------------------------------------------------------------------------------
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/// Driver interfaces.
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pub mod interface {
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/// Device Driver functions.
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pub trait DeviceDriver {
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/// Return a compatibility string for identifying the driver.
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fn compatible(&self) -> &str;
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/// Called by the kernel to bring up the device.
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fn init(&self) -> Result<(), ()> {
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Ok(())
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}
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}
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/// Device driver management functions.
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///
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/// The `BSP` is supposed to supply one global instance.
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pub trait DriverManager {
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/// Return a slice of references to all `BSP`-instantiated drivers.
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///
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/// # Safety
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///
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/// - The order of devices is the order in which `DeviceDriver::init()` is called.
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fn all_device_drivers(&self) -> &[&'static (dyn DeviceDriver + Sync)];
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/// Initialization code that runs after driver init.
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///
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/// For example, device driver code that depends on other drivers already being online.
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fn post_device_driver_init(&self);
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}
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}
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// SPDX-License-Identifier: MIT OR Apache-2.0
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//
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// Copyright (c) 2018-2020 Andre Richter <andre.o.richter@gmail.com>
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//! Trait definitions for coupling `kernel` and `BSP` code.
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//!
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//! ```
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//! +-------------------+
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//! | Interface (Trait) |
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//! | |
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//! +--+-------------+--+
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//! ^ ^
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//! | |
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//! | |
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//! +----------+--+ +--+----------+
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//! | Kernel code | | BSP Code |
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//! | | | |
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//! +-------------+ +-------------+
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//! ```
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/// System console operations.
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pub mod console {
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use core::fmt;
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/// Console write functions.
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pub trait Write {
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/// Write a single character.
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fn write_char(&self, c: char);
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/// Write a Rust format string.
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fn write_fmt(&self, args: fmt::Arguments) -> fmt::Result;
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/// Block execution until the last character has been physically put on the TX wire
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/// (draining TX buffers/FIFOs, if any).
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fn flush(&self);
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}
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/// Console read functions.
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pub trait Read {
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/// Read a single character.
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fn read_char(&self) -> char {
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' '
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}
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/// Clear RX buffers, if any.
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fn clear(&self);
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}
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/// Console statistics.
|
||||
pub trait Statistics {
|
||||
/// Return the number of characters written.
|
||||
fn chars_written(&self) -> usize {
|
||||
0
|
||||
}
|
||||
|
||||
/// Return the number of characters read.
|
||||
fn chars_read(&self) -> usize {
|
||||
0
|
||||
}
|
||||
}
|
||||
|
||||
/// Trait alias for a full-fledged console.
|
||||
pub trait All = Write + Read + Statistics;
|
||||
}
|
||||
|
||||
/// Synchronization primitives.
|
||||
pub mod sync {
|
||||
/// Any object implementing this trait guarantees exclusive access to the data contained within
|
||||
/// the mutex for the duration of the lock.
|
||||
///
|
||||
/// The trait follows the [Rust embedded WG's
|
||||
/// proposal](https://github.com/korken89/wg/blob/master/rfcs/0377-mutex-trait.md) and therefore
|
||||
/// provides some goodness such as [deadlock
|
||||
/// prevention](https://github.com/korken89/wg/blob/master/rfcs/0377-mutex-trait.md#design-decisions-and-compatibility).
|
||||
///
|
||||
/// # Example
|
||||
///
|
||||
/// Since the lock function takes an `&mut self` to enable deadlock-prevention, the trait is
|
||||
/// best implemented **for a reference to a container struct**, and has a usage pattern that
|
||||
/// might feel strange at first:
|
||||
///
|
||||
/// ```
|
||||
/// static MUT: Mutex<RefCell<i32>> = Mutex::new(RefCell::new(0));
|
||||
///
|
||||
/// fn foo() {
|
||||
/// let mut r = &MUT; // Note that r is mutable
|
||||
/// r.lock(|data| *data += 1);
|
||||
/// }
|
||||
/// ```
|
||||
pub trait Mutex {
|
||||
/// Type of data encapsulated by the mutex.
|
||||
type Data;
|
||||
|
||||
/// Creates a critical section and grants temporary mutable access to the encapsulated data.
|
||||
fn lock<R>(&mut self, f: impl FnOnce(&mut Self::Data) -> R) -> R;
|
||||
}
|
||||
}
|
||||
|
||||
/// Driver interfaces.
|
||||
pub mod driver {
|
||||
/// Driver result type, e.g. for indicating successful driver init.
|
||||
pub type Result = core::result::Result<(), ()>;
|
||||
|
||||
/// Device Driver functions.
|
||||
pub trait DeviceDriver {
|
||||
/// Return a compatibility string for identifying the driver.
|
||||
fn compatible(&self) -> &str;
|
||||
|
||||
/// Called by the kernel to bring up the device.
|
||||
fn init(&self) -> Result {
|
||||
Ok(())
|
||||
}
|
||||
}
|
||||
}
|
||||
|
||||
/// Timekeeping interfaces.
|
||||
pub mod time {
|
||||
use core::time::Duration;
|
||||
|
||||
/// Timer functions.
|
||||
pub trait Timer {
|
||||
/// The timer's resolution.
|
||||
fn resolution(&self) -> Duration;
|
||||
|
||||
/// The uptime since power-on of the device.
|
||||
///
|
||||
/// This includes time consumed by firmware and bootloaders.
|
||||
fn uptime(&self) -> Duration;
|
||||
|
||||
/// Spin for a given duration.
|
||||
fn spin_for(&self, duration: Duration);
|
||||
}
|
||||
}
|
||||
@ -0,0 +1,91 @@
|
||||
// SPDX-License-Identifier: MIT OR Apache-2.0
|
||||
//
|
||||
// Copyright (c) 2020 Andre Richter <andre.o.richter@gmail.com>
|
||||
|
||||
//! Synchronization primitives.
|
||||
|
||||
use core::cell::UnsafeCell;
|
||||
|
||||
//--------------------------------------------------------------------------------------------------
|
||||
// Public Definitions
|
||||
//--------------------------------------------------------------------------------------------------
|
||||
|
||||
/// Synchronization interfaces.
|
||||
pub mod interface {
|
||||
|
||||
/// Any object implementing this trait guarantees exclusive access to the data contained within
|
||||
/// the Mutex for the duration of the provided closure.
|
||||
///
|
||||
/// The trait follows the [Rust embedded WG's
|
||||
/// proposal](https://github.com/korken89/wg/blob/master/rfcs/0377-mutex-trait.md) and therefore
|
||||
/// provides some goodness such as [deadlock
|
||||
/// prevention](https://github.com/korken89/wg/blob/master/rfcs/0377-mutex-trait.md#design-decisions-and-compatibility).
|
||||
///
|
||||
/// # Example
|
||||
///
|
||||
/// Since the lock function takes an `&mut self` to enable deadlock-prevention, the trait is
|
||||
/// best implemented **for a reference to a container struct**, and has a usage pattern that
|
||||
/// might feel strange at first:
|
||||
///
|
||||
/// ```
|
||||
/// static MUT: Mutex<RefCell<i32>> = Mutex::new(RefCell::new(0));
|
||||
///
|
||||
/// fn foo() {
|
||||
/// let mut r = &MUT; // Note that r is mutable
|
||||
/// r.lock(|data| *data += 1);
|
||||
/// }
|
||||
/// ```
|
||||
pub trait Mutex {
|
||||
/// The type of encapsulated data.
|
||||
type Data;
|
||||
|
||||
/// Creates a critical section and grants temporary mutable access to the encapsulated data.
|
||||
fn lock<R>(&mut self, f: impl FnOnce(&mut Self::Data) -> R) -> R;
|
||||
}
|
||||
}
|
||||
|
||||
/// A pseudo-lock for teaching purposes.
|
||||
///
|
||||
/// Used to introduce [interior mutability].
|
||||
///
|
||||
/// In contrast to a real Mutex implementation, does not protect against concurrent access from
|
||||
/// other cores to the contained data. This part is preserved for later lessons.
|
||||
///
|
||||
/// The lock will only be used as long as it is safe to do so, i.e. as long as the kernel is
|
||||
/// executing single-threaded, aka only running on a single core with interrupts disabled.
|
||||
///
|
||||
/// [interior mutability]: https://doc.rust-lang.org/std/cell/index.html
|
||||
pub struct NullLock<T: ?Sized> {
|
||||
data: UnsafeCell<T>,
|
||||
}
|
||||
|
||||
//--------------------------------------------------------------------------------------------------
|
||||
// Public Code
|
||||
//--------------------------------------------------------------------------------------------------
|
||||
|
||||
unsafe impl<T: ?Sized> Sync for NullLock<T> {}
|
||||
|
||||
impl<T> NullLock<T> {
|
||||
/// Wraps `data` into a new `NullLock`.
|
||||
pub const fn new(data: T) -> Self {
|
||||
Self {
|
||||
data: UnsafeCell::new(data),
|
||||
}
|
||||
}
|
||||
}
|
||||
|
||||
//------------------------------------------------------------------------------
|
||||
// OS Interface Code
|
||||
//------------------------------------------------------------------------------
|
||||
|
||||
impl<T> interface::Mutex for &NullLock<T> {
|
||||
type Data = T;
|
||||
|
||||
fn lock<R>(&mut self, f: impl FnOnce(&mut Self::Data) -> R) -> R {
|
||||
// In a real lock, there would be code encapsulating this line that ensures that this
|
||||
// mutable reference will ever only be given out once at a time.
|
||||
let data = unsafe { &mut *self.data.get() };
|
||||
|
||||
f(data)
|
||||
}
|
||||
}
|
||||
@ -0,0 +1,35 @@
|
||||
// SPDX-License-Identifier: MIT OR Apache-2.0
|
||||
//
|
||||
// Copyright (c) 2020 Andre Richter <andre.o.richter@gmail.com>
|
||||
|
||||
//! Timer primitives.
|
||||
|
||||
#[cfg(target_arch = "aarch64")]
|
||||
#[path = "_arch/aarch64/time.rs"]
|
||||
mod arch_time;
|
||||
pub use arch_time::*;
|
||||
|
||||
//--------------------------------------------------------------------------------------------------
|
||||
// Public Definitions
|
||||
//--------------------------------------------------------------------------------------------------
|
||||
|
||||
/// Timekeeping interfaces.
|
||||
pub mod interface {
|
||||
use core::time::Duration;
|
||||
|
||||
/// Time management functions.
|
||||
///
|
||||
/// The `BSP` is supposed to supply one global instance.
|
||||
pub trait TimeManager {
|
||||
/// The timer's resolution.
|
||||
fn resolution(&self) -> Duration;
|
||||
|
||||
/// The uptime since power-on of the device.
|
||||
///
|
||||
/// This includes time consumed by firmware and bootloaders.
|
||||
fn uptime(&self) -> Duration;
|
||||
|
||||
/// Spin for a given duration.
|
||||
fn spin_for(&self, duration: Duration);
|
||||
}
|
||||
}
|
||||
Loading…
Reference in New Issue