simplify including DTB file using include_bytes!()

Author: wangrunji0408

kernel/build.rs

@@ -16,19 +16,14 @@ fn main() {
             gen_vector_asm().unwrap();
         }
         "riscv32" => {}
-        "riscv64" => {
-            if board == "rocket_chip" {
-                gen_dtb_asm(&String::from("riscv32"), &board).unwrap();
-            }
-        }
-        "mipsel" => {
-            gen_dtb_asm(&arch, &board).unwrap();
-        }
+        "riscv64" => {}
+        "mipsel" => {}
         "aarch64" => {}
         _ => panic!("Unknown arch {}", arch),
     }
 }
 
+/// Generate assembly file for x86_64 trap vector
 fn gen_vector_asm() -> Result<()> {
     let mut f = File::create("src/arch/x86_64/interrupt/vector.asm").unwrap();
 
@@ -52,32 +47,3 @@ fn gen_vector_asm() -> Result<()> {
     }
     Ok(())
 }
-
-fn gen_dtb_asm(arch: &String, _board: &String) -> Result<()> {
-    let dtb = std::env::var("DTB").unwrap();
-
-    if !Path::new(&dtb).is_file() {
-        panic!("DTB `{}` not found", dtb)
-    }
-
-    let mut f = File::create(format!("src/arch/{}/boot/dtb.gen.s", arch)).unwrap();
-
-    println!("cargo:rerun-if-changed={}", dtb);
-    println!("cargo:rerun-if-env-changed=DTB");
-
-    writeln!(f, "# generated by build.rs - do not edit")?;
-    write!(
-        f,
-        r#"
-    .section .dtb,"a"
-    .align 12
-    .global _dtb_start, _dtb_end
-_dtb_start:
-    .incbin "{}"
-_dtb_end:
-    "#,
-        dtb
-    )?;
-
-    Ok(())
-}

kernel/src/arch/mipsel/board/malta/mod.rs

@@ -14,6 +14,9 @@ pub mod vga;
 
 use fb::FramebufferInfo;
 
+/// Device tree bytes
+pub static DTB: &'static [u8] = include_bytes!("device.dtb");
+
 /// Initialize serial port first
 pub fn init_serial_early() {
     // initialize serial driver

kernel/src/arch/mipsel/board/mipssim/mod.rs

@@ -8,6 +8,9 @@ pub mod fb;
 #[path = "../../../../drivers/serial/16550_reg.rs"]
 pub mod serial;
 
+/// Device tree bytes
+pub static DTB: &'static [u8] = include_bytes!("device.dtb");
+
 /// Initialize serial port first
 pub fn init_serial_early() {
     serial::init(0xbfd003f8);

kernel/src/arch/mipsel/board/thinpad/mod.rs

@@ -11,6 +11,9 @@ pub mod serial;
 use fb::FramebufferInfo;
 use fb::FramebufferResult;
 
+/// Device tree bytes
+pub static DTB: &'static [u8] = include_bytes!("device.dtb");
+
 /// Initialize serial port first
 pub fn init_serial_early() {
     serial::init(0xa3000000);

kernel/src/arch/mipsel/mod.rs

@@ -24,18 +24,13 @@ pub mod board;
 #[path = "board/mipssim/mod.rs"]
 pub mod board;
 
-extern "C" {
-    fn _dtb_start();
-    fn _dtb_end();
-}
-
 #[no_mangle]
 pub extern "C" fn rust_main() -> ! {
     // unsafe { cpu::set_cpu_id(hartid); }
 
     let ebase = cp0::ebase::read_u32();
     let cpu_id = ebase & 0x3ff;
-    let dtb_start = _dtb_start as usize;
+    let dtb_start = board::DTB.as_ptr() as usize;
 
     if cpu_id != BOOT_CPU_ID {
         // TODO: run others_main on other CPU
@@ -79,4 +74,3 @@ const BOOT_CPU_ID: u32 = 0;
 global_asm!(include_str!("boot/context.gen.s"));
 global_asm!(include_str!("boot/entry.gen.s"));
 global_asm!(include_str!("boot/trap.gen.s"));
-global_asm!(include_str!("boot/dtb.gen.s"));

kernel/src/arch/riscv32/board/rocket_chip/mod.rs

@@ -1,5 +1,8 @@
 use crate::memory::phys_to_virt;
 
+/// Device tree bytes
+pub static DTB: &'static [u8] = include_bytes!("device.dtb");
+
 /// Mask all external interrupt except serial.
 pub unsafe fn init_external_interrupt() {
     const HART0_S_MODE_INTERRUPT_ENABLES: *mut u64 = phys_to_virt(0x0C00_2080) as *mut u64;

kernel/src/arch/riscv32/mod.rs

@@ -34,11 +34,7 @@ pub extern "C" fn rust_main(hartid: usize, device_tree_paddr: usize) -> ! {
 
     #[cfg(feature = "board_rocket_chip")]
     {
-        extern "C" {
-            fn _dtb_start();
-            fn _dtb_end();
-        }
-        device_tree_vaddr = _dtb_start as usize;
+        device_tree_vaddr = board::DTB.as_ptr() as usize;
     }
 
     if hartid != BOOT_HART_ID {
@@ -126,5 +122,3 @@ global_asm!(include_str!("boot/entry64.asm"));
 #[cfg(feature = "board_k210")]
 global_asm!(include_str!("boot/entry_k210.asm"));
 global_asm!(include_str!("boot/trap.asm"));
-#[cfg(feature = "board_rocket_chip")]
-global_asm!(include_str!("boot/dtb.gen.s"));