Merge pull request #1 from phil-opp/simplify_pr_15

Simplify cargo features by making `x86_64` a target-specific dependency

Author: remimimimimi

Cargo.toml

@@ -9,15 +9,14 @@ edition = "2018"
 
 [dependencies]
 bitflags = "1.1.0"
-x86_64 = { version = "0.14.0", default-features = false, features = ["instructions"], optional = true }
+
+[target.'cfg(target_arch = "x86_64")'.dependencies]
+x86_64 = { version = "0.14.0", default-features = false, features = ["instructions"] }
 
 [features]
-default = [ "port_nightly"]
-#default = [ "port", "nightly" ]
-port_stable = [ "x86_64/external_asm" ]
-port_nightly = [ "x86_64/inline_asm" ]
-mmio_stable = []
-mmio_nightly = []
+default = [ "nightly"]
+stable = [ "x86_64/external_asm" ]
+nightly = [ "x86_64/inline_asm" ]
 
 [package.metadata.release]
 no-dev-version = true

src/lib.rs

@@ -37,32 +37,12 @@
 
 #![no_std]
 #![warn(missing_docs)]
-#![cfg_attr(feature = "mmio_nightly", feature(const_ptr_offset))]
-
-use core::fmt;
+#![cfg_attr(feature = "nightly", feature(const_ptr_offset))]
 
 use bitflags::bitflags;
 
-#[cfg(any(
-    all(
-        not(any(feature = "port_stable", feature = "port_nightly")),
-        not(any(feature = "mmio_stable", feature = "mmio_nightly"))
-    ),
-    all(
-        any(feature = "port_stable", feature = "port_nightly"),
-        any(feature = "mmio_stable", feature = "mmio_nightly")
-    )
-))]
-compile_error!("One of these features must be enabled: `port_{stable, nightly}`, `mmio_{stable, nightly}`");
-
-#[cfg(any(feature = "mmio_stable", feature = "mmio_nightly"))]
-use core::sync::atomic::{
-    AtomicPtr,
-    Ordering,
-};
-
-#[cfg(any(feature = "port_stable", feature = "port_nightly"))]
-use x86_64::instructions::port::Port;
+#[cfg(not(any(feature = "stable", feature = "nightly")))]
+compile_error!("Either the `stable` or `nightly` feature must be enabled");
 
 macro_rules! wait_for {
     ($cond:expr) => {
@@ -72,6 +52,14 @@ macro_rules! wait_for {
     };
 }
 
+pub mod mmio;
+#[cfg(target_arch = "x86_64")]
+pub mod x86_64;
+
+#[cfg(target_arch = "x86_64")]
+pub use crate::x86_64::SerialPort;
+pub use crate::mmio::MmioSerialPort;
+
 bitflags! {
     /// Interrupt enable flags
     struct IntEnFlags: u8 {
@@ -92,235 +80,3 @@ bitflags! {
         // 6 and 7 unknown
     }
 }
-
-#[cfg(any(feature = "port_stable", feature = "port_nightly"))]
-/// An interface to a serial port that allows sending out individual bytes.
-pub struct SerialPort {
-    data: Port<u8>,
-    int_en: Port<u8>,
-    fifo_ctrl: Port<u8>,
-    line_ctrl: Port<u8>,
-    modem_ctrl: Port<u8>,
-    line_sts: Port<u8>,
-}
-
-#[cfg(any(feature = "port_stable", feature = "port_nightly"))]
-impl SerialPort {
-    /// Creates a new serial port interface on the given I/O port.
-    ///
-    /// This function is unsafe because the caller must ensure that the given base address
-    /// really points to a serial port device.
-    #[cfg(feature = "port_nightly")]
-    pub const unsafe fn new(base: u16) -> Self {
-        Self {
-            data: Port::new(base),
-            int_en: Port::new(base + 1),
-            fifo_ctrl: Port::new(base + 2),
-            line_ctrl: Port::new(base + 3),
-            modem_ctrl: Port::new(base + 4),
-            line_sts: Port::new(base + 5),
-        }
-    }
-
-    /// Creates a new serial port interface on the given I/O port.
-    ///
-    /// This function is unsafe because the caller must ensure that the given base address
-    /// really points to a serial port device.
-    #[cfg(feature = "port_stable")]
-    pub unsafe fn new(base: u16) -> Self {
-        Self {
-            data: Port::new(base),
-            int_en: Port::new(base + 1),
-            fifo_ctrl: Port::new(base + 2),
-            line_ctrl: Port::new(base + 3),
-            modem_ctrl: Port::new(base + 4),
-            line_sts: Port::new(base + 5),
-        }
-    }
-
-    /// Initializes the serial port.
-    ///
-    /// The default configuration of [38400/8-N-1](https://en.wikipedia.org/wiki/8-N-1) is used.
-    pub fn init(&mut self) {
-        unsafe {
-            // Disable interrupts
-            self.int_en.write(0x00);
-
-            // Enable DLAB
-            self.line_ctrl.write(0x80);
-
-            // Set maximum speed to 38400 bps by configuring DLL and DLM
-            self.data.write(0x03);
-            self.int_en.write(0x00);
-
-            // Disable DLAB and set data word length to 8 bits
-            self.line_ctrl.write(0x03);
-
-            // Enable FIFO, clear TX/RX queues and
-            // set interrupt watermark at 14 bytes
-            self.fifo_ctrl.write(0xC7);
-
-            // Mark data terminal ready, signal request to send
-            // and enable auxilliary output #2 (used as interrupt line for CPU)
-            self.modem_ctrl.write(0x0B);
-
-            // Enable interrupts
-            self.int_en.write(0x01);
-        }
-    }
-
-    fn line_sts(&mut self) -> LineStsFlags {
-        unsafe { LineStsFlags::from_bits_truncate(self.line_sts.read()) }
-    }
-
-    /// Sends a byte on the serial port.
-    pub fn send(&mut self, data: u8) {
-        unsafe {
-            match data {
-                8 | 0x7F => {
-                    wait_for!(self.line_sts().contains(LineStsFlags::OUTPUT_EMPTY));
-                    self.data.write(8);
-                    wait_for!(self.line_sts().contains(LineStsFlags::OUTPUT_EMPTY));
-                    self.data.write(b' ');
-                    wait_for!(self.line_sts().contains(LineStsFlags::OUTPUT_EMPTY));
-                    self.data.write(8)
-                },
-                _ => {
-                    wait_for!(self.line_sts().contains(LineStsFlags::OUTPUT_EMPTY));
-                    self.data.write(data);
-                },
-            }
-        }
-    }
-
-    /// Receives a byte on the serial port.
-    pub fn receive(&mut self) -> u8 {
-        unsafe {
-            wait_for!(self.line_sts().contains(LineStsFlags::INPUT_FULL));
-            self.data.read()
-        }
-    }
-}
-
-/// An interface to a serial port that allows sending out individual bytes.
-#[cfg(any(feature = "mmio_stable", feature = "mmio_nightly"))]
-pub struct MmioSerialPort {
-    data: AtomicPtr<u8>,
-    int_en: AtomicPtr<u8>,
-    fifo_ctrl: AtomicPtr<u8>,
-    line_ctrl: AtomicPtr<u8>,
-    modem_ctrl: AtomicPtr<u8>,
-    line_sts: AtomicPtr<u8>,
-}
-
-#[cfg(any(feature = "mmio_stable", feature = "mmio_nightly"))]
-impl SerialPort {
-    /// Creates a new serial port interface on the given memory mapped address.
-    ///
-    /// This function is unsafe because the caller must ensure that the given base address
-    /// really points to a serial port device.
-    #[cfg(feature = "mmio_nightly")]
-    pub const unsafe fn new(base: usize) -> Self {
-        let base_pointer = base as *mut u8;
-        Self {
-            data: AtomicPtr::new(base_pointer),
-            int_en: AtomicPtr::new(base_pointer.add(1)),
-            fifo_ctrl: AtomicPtr::new(base_pointer.add(2)),
-            line_ctrl: AtomicPtr::new(base_pointer.add(3)),
-            modem_ctrl: AtomicPtr::new(base_pointer.add(4)),
-            line_sts: AtomicPtr::new(base_pointer.add(5)),
-        }
-    }
-
-    #[cfg(feature = "mmio_stable")]
-    pub unsafe fn new(base: usize) -> Self {
-        let base_pointer = base as *mut u8;
-        Self {
-            data: AtomicPtr::new(base_pointer),
-            int_en: AtomicPtr::new(base_pointer.add(1)),
-            fifo_ctrl: AtomicPtr::new(base_pointer.add(2)),
-            line_ctrl: AtomicPtr::new(base_pointer.add(3)),
-            modem_ctrl: AtomicPtr::new(base_pointer.add(4)),
-            line_sts: AtomicPtr::new(base_pointer.add(5)),
-        }
-    }
-
-    /// Initializes the serial port.
-    ///
-    /// The default configuration of [38400/8-N-1](https://en.wikipedia.org/wiki/8-N-1) is used.
-    pub fn init(&mut self) {
-        let self_int_en = self.int_en.load(Ordering::Relaxed);
-        let self_line_ctrl = self.line_ctrl.load(Ordering::Relaxed);
-        let self_data = self.data.load(Ordering::Relaxed);
-        let self_fifo_ctrl = self.fifo_ctrl.load(Ordering::Relaxed);
-        let self_modem_ctrl = self.modem_ctrl.load(Ordering::Relaxed);
-        unsafe {
-            // Disable interrupts
-            self_int_en.write(0x00);
-
-            // Enable DLAB
-            self_line_ctrl.write(0x80);
-
-            // Set maximum speed to 38400 bps by configuring DLL and DLM
-            self_data.write(0x03);
-            self_int_en.write(0x00);
-
-            // Disable DLAB and set data word length to 8 bits
-            self_line_ctrl.write(0x03);
-
-            // Enable FIFO, clear TX/RX queues and
-            // set interrupt watermark at 14 bytes
-            self_fifo_ctrl.write(0xC7);
-
-            // Mark data terminal ready, signal request to send
-            // and enable auxilliary output #2 (used as interrupt line for CPU)
-            self_modem_ctrl.write(0x0B);
-
-            // Enable interrupts
-            self_int_en.write(0x01);
-        }
-    }
-
-    fn line_sts(&mut self) -> LineStsFlags {
-        unsafe { LineStsFlags::from_bits_truncate(*self.line_sts.load(Ordering::Relaxed)) }
-    }
-
-    /// Sends a byte on the serial port.
-    pub fn send(&mut self, data: u8) {
-        let self_data = self.data.load(Ordering::Relaxed);
-        unsafe {
-            match data {
-                8 | 0x7F => {
-                    wait_for!(self.line_sts().contains(LineStsFlags::OUTPUT_EMPTY));
-                    self_data.write(8);
-                    wait_for!(self.line_sts().contains(LineStsFlags::OUTPUT_EMPTY));
-                    self_data.write(b' ');
-                    wait_for!(self.line_sts().contains(LineStsFlags::OUTPUT_EMPTY));
-                    self_data.write(8)
-                },
-                _ => {
-                    wait_for!(self.line_sts().contains(LineStsFlags::OUTPUT_EMPTY));
-                    self_data.write(data);
-                },
-            }
-        }
-    }
-
-    /// Receives a byte on the serial port.
-    pub fn receive(&mut self) -> u8 {
-        let self_data = self.data.load(Ordering::Relaxed);
-        unsafe {
-            wait_for!(self.line_sts().contains(LineStsFlags::INPUT_FULL));
-            self_data.read()
-        }
-    }
-}
-
-impl fmt::Write for SerialPort {
-    fn write_str(&mut self, s: &str) -> fmt::Result {
-        for byte in s.bytes() {
-            self.send(byte);
-        }
-        Ok(())
-    }
-}