It boots!

.cargo/config.toml

@@ -1,2 +1,3 @@
 [build]
+rustflags = "-C relocation-model=static"
 target = "x86_64-unknown-none"

.envrc

@@ -0,0 +1 @@
+use nix

.gitignore

@@ -1 +1,2 @@
 /target
+/iso/gila.iso

README.md

@@ -24,6 +24,21 @@ Licensed under the GNU Public License v3. See [LICENSE](LICENSE) for details.
 - [process.rs](src/process.rs): Process types and functions.
 - [resources.rs](src/resources.rs): Resources that are accessible from multiple parts of the code.
 
-## Building and running - TODO
+## Building and running
 
-This section is under construction.
+To build an ISO image that you can boot, there are several prerequisites:
+
+- `limine` command installed
+- `xorriso` command installed
+
+Then run the [build_iso.sh](build_iso.sh) script. It will generate `gila.iso`.
+
+Running the kernel requires qemu.
+
+You can install all these dependencies automatically by using `nix-shell` and
+supplying [shell.nix](shell.nix) as an argument.
+
+## Credits
+
+The linker script stuff is from [limine-rust-template](https://github.com/jasondyoungberg/limine-rust-template),
+which is available under the BSD 0-Clause License.

build.rs

@@ -0,0 +1,8 @@
+fn main() {
+
+    let arch = std::env::var("CARGO_CFG_TARGET_ARCH").unwrap();
+    // Tell cargo to pass the linker script to the linker..
+    println!("cargo:rustc-link-arg=-Tlinker-scripts/linker-{arch}.ld");
+    // ..and to re-run if it changes.
+    println!("cargo:rerun-if-changed=linker-scripts/linker-{arch}.ld");
+}

build_iso.sh

@@ -0,0 +1,29 @@
+#!/bin/bash
+
+if [ -z "$1" ]; then
+    echo "Argument 1 must be the Rust target triple."
+    exit 1
+fi
+
+SCRIPTPATH="$( cd -- "$(dirname "$0")" >/dev/null 2>&1 || exit 1 ; pwd -P )"
+cd "$SCRIPTPATH" || exit 1
+
+rm -rf ./iso/
+rm ./gila.iso
+#cargo clean
+
+mkdir -p ./iso/limine/
+cp ./limine.conf ./iso/
+cp /usr/share/limine/limine-bios.sys ./iso/limine/
+cp /usr/share/limine/limine-bios-cd.bin ./iso/limine/
+cp /usr/share/limine/limine-uefi-cd.bin ./iso/limine/
+
+cargo build --target="$1" --release
+cp target/"$1"/release/gila ./iso/
+
+xorriso -as mkisofs -b limine/limine-bios-cd.bin -no-emul-boot \
+    -boot-load-size 4 -boot-info-table --efi-boot \
+    limine/limine-uefi-cd.bin -efi-boot-part --efi-boot-image \
+    --protective-msdos-label iso -o gila.iso
+
+limine bios-install gila.iso

limine.conf

@@ -2,4 +2,4 @@ timeout: 5
 
 /Gila
     protocol: limine
-    kernel_path: boot():/gila.bin
+    kernel_path: boot():/gila

linker-scripts/linker-aarch64.ld

@@ -0,0 +1,63 @@
+/* Tell the linker that we want an aarch64 ELF64 output file */
+OUTPUT_FORMAT(elf64-littleaarch64)
+
+/* We want the symbol main to be our entry point */
+ENTRY(main)
+
+/* Define the program headers we want so the bootloader gives us the right */
+/* MMU permissions; this also allows us to exert more control over the linking */
+/* process. */
+PHDRS
+{
+    text    PT_LOAD;
+    rodata  PT_LOAD;
+    data    PT_LOAD;
+}
+
+SECTIONS
+{
+    /* We want to be placed in the topmost 2GiB of the address space, for optimisations */
+    /* and because that is what the Limine spec mandates. */
+    /* Any address in this region will do, but often 0xffffffff80000000 is chosen as */
+    /* that is the beginning of the region. */
+    . = 0xffffffff80000000;
+
+    .text : {
+        *(.text .text.*)
+    } :text
+
+    /* Move to the next memory page for .rodata */
+    . = ALIGN(CONSTANT(MAXPAGESIZE));
+
+    .rodata : {
+        *(.rodata .rodata.*)
+    } :rodata
+
+    /* Move to the next memory page for .data */
+    . = ALIGN(CONSTANT(MAXPAGESIZE));
+
+    .data : {
+        *(.data .data.*)
+
+        /* Place the sections that contain the Limine requests as part of the .data */
+        /* output section. */
+        KEEP(*(.requests_start_marker))
+        KEEP(*(.requests))
+        KEEP(*(.requests_end_marker))
+    } :data
+
+    /* NOTE: .bss needs to be the last thing mapped to :data, otherwise lots of */
+    /* unnecessary zeros will be written to the binary. */
+    /* If you need, for example, .init_array and .fini_array, those should be placed */
+    /* above this. */
+    .bss : {
+        *(.bss .bss.*)
+        *(COMMON)
+    } :data
+
+    /* Discard .note.* and .eh_frame* since they may cause issues on some hosts. */
+    /DISCARD/ : {
+        *(.eh_frame*)
+        *(.note .note.*)
+    }
+}

linker-scripts/linker-loongarch64.ld

@@ -0,0 +1,63 @@
+/* Tell the linker that we want a loongarch64 ELF64 output file */
+OUTPUT_FORMAT(elf64-loongarch)
+
+/* We want the symbol main to be our entry point */
+ENTRY(main)
+
+/* Define the program headers we want so the bootloader gives us the right */
+/* MMU permissions; this also allows us to exert more control over the linking */
+/* process. */
+PHDRS
+{
+    text    PT_LOAD;
+    rodata  PT_LOAD;
+    data    PT_LOAD;
+}
+
+SECTIONS
+{
+    /* We want to be placed in the topmost 2GiB of the address space, for optimisations */
+    /* and because that is what the Limine spec mandates. */
+    /* Any address in this region will do, but often 0xffffffff80000000 is chosen as */
+    /* that is the beginning of the region. */
+    . = 0xffffffff80000000;
+
+    .text : {
+        *(.text .text.*)
+    } :text
+
+    /* Move to the next memory page for .rodata */
+    . = ALIGN(CONSTANT(MAXPAGESIZE));
+
+    .rodata : {
+        *(.rodata .rodata.*)
+    } :rodata
+
+    /* Move to the next memory page for .data */
+    . = ALIGN(CONSTANT(MAXPAGESIZE));
+
+    .data : {
+        *(.data .data.*)
+
+        /* Place the sections that contain the Limine requests as part of the .data */
+        /* output section. */
+        KEEP(*(.requests_start_marker))
+        KEEP(*(.requests))
+        KEEP(*(.requests_end_marker))
+    } :data
+
+    /* NOTE: .bss needs to be the last thing mapped to :data, otherwise lots of */
+    /* unnecessary zeros will be written to the binary. */
+    /* If you need, for example, .init_array and .fini_array, those should be placed */
+    /* above this. */
+    .bss : {
+        *(.bss .bss.*)
+        *(COMMON)
+    } :data
+
+    /* Discard .note.* and .eh_frame* since they may cause issues on some hosts. */
+    /DISCARD/ : {
+        *(.eh_frame*)
+        *(.note .note.*)
+    }
+}

linker-scripts/linker-riscv64.ld

@@ -0,0 +1,66 @@
+/* Tell the linker that we want a riscv64 ELF64 output file */
+OUTPUT_FORMAT(elf64-littleriscv)
+
+/* We want the symbol main to be our entry point */
+ENTRY(main)
+
+/* Define the program headers we want so the bootloader gives us the right */
+/* MMU permissions; this also allows us to exert more control over the linking */
+/* process. */
+PHDRS
+{
+    text    PT_LOAD;
+    rodata  PT_LOAD;
+    data    PT_LOAD;
+}
+
+SECTIONS
+{
+    /* We want to be placed in the topmost 2GiB of the address space, for optimisations */
+    /* and because that is what the Limine spec mandates. */
+    /* Any address in this region will do, but often 0xffffffff80000000 is chosen as */
+    /* that is the beginning of the region. */
+    . = 0xffffffff80000000;
+
+    .text : {
+        *(.text .text.*)
+    } :text
+
+    /* Move to the next memory page for .rodata */
+    . = ALIGN(CONSTANT(MAXPAGESIZE));
+
+    .rodata : {
+        *(.rodata .rodata.*)
+    } :rodata
+
+    /* Move to the next memory page for .data */
+    . = ALIGN(CONSTANT(MAXPAGESIZE));
+
+    .data : {
+        *(.data .data.*)
+
+        /* Place the sections that contain the Limine requests as part of the .data */
+        /* output section. */
+        KEEP(*(.requests_start_marker))
+        KEEP(*(.requests))
+        KEEP(*(.requests_end_marker))
+
+        *(.sdata .sdata.*)
+    } :data
+
+    /* NOTE: .bss needs to be the last thing mapped to :data, otherwise lots of */
+    /* unnecessary zeros will be written to the binary. */
+    /* If you need, for example, .init_array and .fini_array, those should be placed */
+    /* above this. */
+    .bss : {
+        *(.sbss .sbss.*)
+        *(.bss .bss.*)
+        *(COMMON)
+    } :data
+
+    /* Discard .note.* and .eh_frame* since they may cause issues on some hosts. */
+    /DISCARD/ : {
+        *(.eh_frame*)
+        *(.note .note.*)
+    }
+}

linker-scripts/linker-x86_64.ld

@@ -0,0 +1,63 @@
+/* Tell the linker that we want an x86_64 ELF64 output file */
+OUTPUT_FORMAT(elf64-x86-64)
+
+/* We want the symbol main to be our entry point */
+ENTRY(main)
+
+/* Define the program headers we want so the bootloader gives us the right */
+/* MMU permissions; this also allows us to exert more control over the linking */
+/* process. */
+PHDRS
+{
+    text    PT_LOAD;
+    rodata  PT_LOAD;
+    data    PT_LOAD;
+}
+
+SECTIONS
+{
+    /* We want to be placed in the topmost 2GiB of the address space, for optimisations */
+    /* and because that is what the Limine spec mandates. */
+    /* Any address in this region will do, but often 0xffffffff80000000 is chosen as */
+    /* that is the beginning of the region. */
+    . = 0xffffffff80000000;
+
+    .text : {
+        *(.text .text.*)
+    } :text
+
+    /* Move to the next memory page for .rodata */
+    . = ALIGN(CONSTANT(MAXPAGESIZE));
+
+    .rodata : {
+        *(.rodata .rodata.*)
+    } :rodata
+
+    /* Move to the next memory page for .data */
+    . = ALIGN(CONSTANT(MAXPAGESIZE));
+
+    .data : {
+        *(.data .data.*)
+
+        /* Place the sections that contain the Limine requests as part of the .data */
+        /* output section. */
+        KEEP(*(.requests_start_marker))
+        KEEP(*(.requests))
+        KEEP(*(.requests_end_marker))
+    } :data
+
+    /* NOTE: .bss needs to be the last thing mapped to :data, otherwise lots of */
+    /* unnecessary zeros will be written to the binary. */
+    /* If you need, for example, .init_array and .fini_array, those should be placed */
+    /* above this. */
+    .bss : {
+        *(.bss .bss.*)
+        *(COMMON)
+    } :data
+
+    /* Discard .note.* and .eh_frame* since they may cause issues on some hosts. */
+    /DISCARD/ : {
+        *(.eh_frame*)
+        *(.note .note.*)
+    }
+}

shell.nix

@@ -0,0 +1,27 @@
+let
+
+  nixpkgs = fetchTarball "https://github.com/NixOS/nixpkgs/tarball/nixos-24.05";
+
+  pkgs = import nixpkgs { config = {}; overlays = []; };
+
+in
+
+
+pkgs.mkShell {
+
+  packages = with pkgs; [
+
+    bash
+    limine
+    xorriso
+    rustup
+    qemu
+
+  ];
+
+  shellHook = ''
+    rustup default stable;
+    rustup target add x86_64-unknown-none
+  '';
+
+}

src/boot.rs

@@ -1,6 +1,17 @@
 #![allow(dead_code)]
 
-use limine::{request::SmpRequest, BaseRevision};
+use limine::{request::*, BaseRevision};
 
+#[used]
+#[unsafe(link_section = ".requests_start_marker")]
+static _START_MARKER: RequestsStartMarker = RequestsStartMarker::new();
+#[used]
+#[unsafe(link_section = ".requests_end_marker")]
+static _END_MARKER: RequestsEndMarker = RequestsEndMarker::new();
+
+#[used]
+#[unsafe(link_section = ".requests")]
 pub static BASE_REVISION: BaseRevision = limine::BaseRevision::new();
+#[used]
+#[unsafe(link_section = ".requests")]
 pub static SMP_REQUEST: SmpRequest = limine::request::SmpRequest::new();

src/display.rs

@@ -1,8 +1,9 @@
+#![allow(dead_code)]
 
 use vga;
 pub use vga::writers::TextWriter;
 
-struct TextDisplay {
+pub struct TextDisplay {
     writer: vga::writers::Text80x25,
     column: usize,
     row: usize,

src/main.rs

@@ -5,6 +5,8 @@
 #![allow(dead_code)]
 #![allow(unused_imports)]
 
+use core::arch::asm;
+
 use gila::boot::*;
 use gila::process;
 use gila::memory;
@@ -13,10 +15,21 @@ use gila::boot;
 use gila::display::{self, TextWriter};
 
 #[unsafe(no_mangle)]
-pub extern "C" fn main() {
+unsafe extern "C" fn main() -> !{
 
     assert!(BASE_REVISION.is_supported());
 
     let _smp_response = SMP_REQUEST.get_response();
 
+    loop {
+        unsafe {
+            #[cfg(target_arch = "x86_64")]
+            asm!("hlt");
+            #[cfg(any(target_arch = "aarch64", target_arch = "riscv64"))]
+            asm!("wfi");
+            #[cfg(target_arch = "loongarch64")]
+            asm!("idle 0");
+        }
+    }
+
 }