wip

Author: phil-opp

real_mode/Cargo.toml

@@ -9,6 +9,7 @@ edition = "2018"
 [dependencies]
 
 [profile.release]
-opt-level = "z"
+opt-level = "s"
 lto = true
 debug = true
+codegen-units = 1

real_mode/build.rs

@@ -0,0 +1,45 @@
+use std::process::Command;
+use std::env;
+use std::fs::{self, File};
+use std::path::Path;
+
+fn main() {
+    let out_dir = env::var("OUT_DIR").unwrap();
+
+    // first stage
+    let mut cmd = Command::new("cargo");
+    cmd.arg("xbuild").arg("--release");
+    cmd.arg("--manifest-path=first_stage/Cargo.toml");
+    cmd.arg("-Z").arg("unstable-options");
+    cmd.arg("--out-dir").arg(&out_dir);
+    let status = cmd.status().unwrap();
+    assert!(status.success());
+    
+    // second stage
+    let mut cmd = Command::new("cargo");
+    cmd.arg("xbuild").arg("--release");
+    cmd.arg("--manifest-path=second_stage/Cargo.toml");
+    cmd.arg("-Z").arg("unstable-options");
+    cmd.arg("--out-dir").arg(&out_dir);
+    let status = cmd.status().unwrap();
+    assert!(status.success());
+
+    let concat_script = Path::new(&out_dir).join("concat.mri");
+    fs::write(&concat_script, "
+        create libreal_mode.a
+        addlib libfirst_stage.a
+        addlib libsecond_stage.a
+        save
+        end
+    ").unwrap();
+
+    // concat archives
+    let mut cmd = Command::new("ar");
+    cmd.arg("-M").stdin(File::open(concat_script).unwrap());
+    cmd.current_dir(&out_dir);
+    let status = cmd.status().unwrap();
+    assert!(status.success());
+    
+    println!("cargo:rustc-link-search=native={}", out_dir);
+    println!("cargo:rustc-link-lib=static=real_mode");
+}

real_mode/first_stage/.gitignore

@@ -0,0 +1 @@
+/target

real_mode/first_stage/Cargo.lock

@@ -0,0 +1,20 @@
+[package]
+name = "first_stage"
+version = "0.1.0"
+authors = ["Philipp Oppermann <[email protected]>"]
+edition = "2018"
+
+# See more keys and their definitions at https://doc.rust-lang.org/cargo/reference/manifest.html
+
+[lib]
+name = "first_stage"
+crate-type = ["staticlib"]
+
+[dependencies]
+
+
+[profile.release]
+opt-level = "s"
+lto = true
+codegen-units = 1
+debug = true

real_mode/first_stage/Cargo.toml

@@ -74,8 +74,19 @@ check_int13h_extensions:
     jc no_int13h_extensions
 
 rust:
-    push dx     # pass disk number as argument
-    call rust_main
+    # push arguments
+arg_0:
+    push dx     # disk number
+    lea eax, _bootloader_start
+arg_1:
+    push eax
+    lea eax, _second_stage_end
+arg_2:
+    push eax
+    lea eax, _second_stage_start
+arg_3:
+    push eax
+    call first_stage
 
 spin:
     hlt

real_mode/src/boot.s renamed to real_mode/first_stage/src/boot.s

@@ -0,0 +1,68 @@
+#![feature(asm, global_asm)]
+#![no_std]
+
+global_asm!(include_str!("boot.s"));
+
+mod dap;
+
+extern "C" {
+    fn second_stage(disk_number: u16);
+}
+
+/// Test function
+#[no_mangle]
+pub extern "C" fn first_stage(second_stage_start: u32, second_stage_end: u32, bootloader_start: u32, disk_number: u16) {
+    load_second_stage(second_stage_start, second_stage_end, bootloader_start, disk_number);
+    unsafe { second_stage(disk_number); }
+}
+
+fn load_second_stage(second_stage_start: u32, second_stage_end: u32, bootloader_start: u32, disk_number: u16) {
+    use dap::DiskAddressPacket;
+
+    let file_offset = (second_stage_start - bootloader_start) as u64;
+    let size = (second_stage_end - second_stage_start) as u32;
+
+    let dap = DiskAddressPacket::new(second_stage_start as u16, file_offset, size);
+    unsafe { dap.perform_load(disk_number) }
+}
+
+#[no_mangle]
+pub extern fn print_char(c: u8) {
+    let ax = u16::from(c) | 0x0e00;
+    unsafe {
+        asm!("int 0x10" :: "{ax}"(ax), "{bx}"(0) :: "intel" );
+    }
+}
+
+#[no_mangle]
+pub extern "C" fn dap_load_failed() -> ! {
+    err(b'1');
+}
+
+#[no_mangle]
+pub extern "C" fn no_int13h_extensions() -> ! {
+    err(b'2');
+}
+
+#[cold]
+fn err(code: u8) -> ! {
+    for &c in b"Err:" {
+        print_char(c);
+    }
+    print_char(code);
+    loop {
+        hlt()
+    }
+}
+
+fn hlt() {
+    unsafe {
+        asm!("hlt":::: "intel","volatile");
+    }
+}
+
+#[panic_handler]
+pub fn panic(_info: &core::panic::PanicInfo) -> ! {
+    err(b'P');
+}
+

real_mode/src/dap.rs renamed to real_mode/first_stage/src/dap.rs

@@ -11,15 +11,15 @@ SECTIONS {
     {
         *(.boot)
     }
-    .text :
+    .first_stage_text :
     {
-        *(.text .text.*)
+        *first_stage*(.text .text.*)
     }
-    .data :
+    .first_stage_data :
     {
-        *(.rodata .rodata.*)
-        *(.data .data.*)
-        *(.got)
+        *first_stage*(.rodata .rodata.*)
+        *first_stage*(.data .data.*)
+        *first_stage*(.got .got.*)
     }
 
     . = 0x7c00 + 510;
@@ -29,7 +29,31 @@ SECTIONS {
     }
 
     _second_stage_start = .;
-    .second_stage :
+
+    .second_stage_text :
+    {
+        *second_stage*(.text .text.*)
+    }
+    .second_stage_data :
+    {
+        *second_stage*(.rodata .rodata.*)
+        *second_stage*(.data .data.*)
+        *second_stage*(.got .got.*)
+    }
+
+    .text :
+    {
+        *(.text .text.*)
+    }
+
+    .data :
+    {
+        *(.rodata .rodata.*)
+        *(.data .data.*)
+        *(.got .got.*)
+    }
+
+    .asm :
     {
         *(.second_stage)
     }

real_mode/first_stage/src/lib.rs

@@ -0,0 +1 @@
+/target