feat: link.ld,naked asm

.cargo/config.toml

@@ -0,0 +1,7 @@
+[build]
+target = "x86_64-unknown-none"
+
+[target.x86_64-unknown-none]
+rustflags = [
+    "-C", "relocation-model=static",
+]

crates/rkos-arch/Cargo.toml

@@ -0,0 +1,16 @@
+[package]
+name = "rkos-arch"
+version = "0.1.0"
+edition = "2024"
+authors.workspace = true
+categories.workspace = true
+keywords.workspace = true
+license.workspace = true
+description.workspace = true
+rust-version.workspace = true
+
+[dependencies]
+
+[lib]
+test = false
+doctest = false

crates/rkos-arch/src/lib.rs

@@ -0,0 +1,3 @@
+#![no_std]
+#![no_main]
+pub mod x86;

crates/rkos-arch/src/x86/link.ld

@@ -0,0 +1,70 @@
+OUTPUT_ARCH(i386:x86-64)
+ENTRY(_start)
+
+/* kernel memory map
+ *
+ *   Physical Address       Memory Content
+ *   ----------------       -----------------------
+ *   0x100000        -----> +-----------------------+ <--- KERNEL_BASE_ADDRESS
+ *                          |      .text.entry      | (boot scripts)
+ *                          |-----------------------|
+ *                          |         .text         | (code)
+ *                          |-----------------------| <--- etext (4K aligned)
+ *                          |        .rodata        | (read-only data)
+ *                          |-----------------------| <--- erodata (4K aligned)
+ *                          |         .data         | (initialized data)
+ *                          |-----------------------| <--- edata (4K aligned)
+ *                          |      .bss.stack       | (kernel stack space)
+ *                          |-----------------------|
+ *                          |         .bss          | (uninitialized data)
+ *                          |-----------------------| <--- ebss (4K aligned)
+ *                          +-----------------------+ <--- ekernel (Heap Start)
+ *
+ */
+
+
+/* x86_64 kernel base address */
+KERNEL_BASE_ADDRESS = 0x100000;
+
+SECTIONS {
+    . = KERNEL_BASE_ADDRESS;
+
+    /* kernel code */
+    .text : {
+        stext = .;              
+        *(.text.entry)          
+        *(.text .text.*)        
+        . = ALIGN(4096);
+        etext = .;              
+    }
+
+    /* kernel rodata */
+    .rodata : {
+        srodata = .;
+        *(.rodata .rodata.*)
+        . = ALIGN(4096);
+        erodata = .;
+    }
+
+    /* kernel data */
+    .data : {
+        sdata = .;
+        *(.data .data.*)
+        . = ALIGN(4096);
+        edata = .;
+    }
+
+    /* kernel bss */
+    .bss : {
+        sbss = .;
+        *(.bss.stack)           /* kernel stack */
+        *(.bss .bss.*)
+        *(COMMON)
+        . = ALIGN(4096);
+        ebss = .;
+    }
+
+    /* kernel end */
+    . = ALIGN(4096);
+    ekernel = .;
+}

crates/rkos-arch/src/x86/mod.rs

@@ -0,0 +1 @@
+

crates/rkos/build.rs

@@ -0,0 +1,15 @@
+use std::{env, path::PathBuf};
+fn main() {
+    if env::var("CARGO_CFG_TARGET_ARCH").unwrap_or_default() == "x86_64" {
+        let manifest_dir = PathBuf::from(env::var("CARGO_MANIFEST_DIR").unwrap());
+        // link scripts in rkos-arch/src/x86
+        let link_ld_path = manifest_dir
+            .parent()
+            .unwrap()
+            .join("rkos-arch")
+            .join("src")
+            .join("x86")
+            .join("link.ld");
+        println!("cargo:rustc-link-arg=-T{}", link_ld_path.display());
+    }
+}

crates/rkos/src/main.rs

@@ -1,3 +1,40 @@
-fn main() {
-    println!("Hello, world!");
+#![no_std]
+#![no_main]
+
+use core::arch::global_asm;
+use core::panic::PanicInfo;
+
+global_asm!(
+    r#"
+    .section .text.entry
+    .align 4
+
+    .global multiboot_header
+    multiboot_header:
+
+    .long 0x1badb002
+    .long 0x00010000
+    .long -(0x1badb002 + 0x00010000)
+
+    .long multiboot_header
+    .long stext
+    .long edata
+    .long ebss
+    .long _start
+
+    .global _start
+    _start:
+    .code32
+        mov eax, 0x4f4f4f4f
+        mov dword ptr [0xb8000], eax
+
+    .loop:
+        hlt
+        jmp .loop
+    "#
+);
+
+#[panic_handler]
+fn panic(_info: &PanicInfo) -> ! {
+    loop {}
 }