// SPDX-License-Identifier: MIT OR Apache-2.0 // // Copyright (c) 2018-2020 Andre Richter //! BSP console facilities. use crate::console; use core::fmt; //-------------------------------------------------------------------------------------------------- // Private Definitions //-------------------------------------------------------------------------------------------------- /// A mystical, magical device for generating QEMU output out of the void. struct QEMUOutput; //-------------------------------------------------------------------------------------------------- // Private Code //-------------------------------------------------------------------------------------------------- /// Implementing `core::fmt::Write` enables usage of the `format_args!` macros, which in turn are /// used to implement the `kernel`'s `print!` and `println!` macros. By implementing `write_str()`, /// we get `write_fmt()` automatically. /// /// See [`src/print.rs`]. /// /// [`src/print.rs`]: ../../print/index.html impl fmt::Write for QEMUOutput { fn write_str(&mut self, s: &str) -> fmt::Result { for c in s.chars() { unsafe { core::ptr::write_volatile(0x3F20_1000 as *mut u8, c as u8); } } Ok(()) } } //-------------------------------------------------------------------------------------------------- // Public Code //-------------------------------------------------------------------------------------------------- /// Return a reference to the console. pub fn console() -> impl console::interface::Write { QEMUOutput {} }