Load kernel on qemu/k210.

os/src/entry.asm

@@ -0,0 +1,12 @@
+    .section .text.entry
+    .globl _start
+_start:
+    la sp, boot_stack_top
+    call rust_main
+
+    .section .bss.stack
+    .globl boot_stack
+boot_stack:
+    .space 4096 * 16
+    .globl boot_stack_top
+boot_stack_top:

os/src/linker.ld

@@ -0,0 +1,48 @@
+OUTPUT_ARCH(riscv)
+ENTRY(_start)
+BASE_ADDRESS = 0x80020000;
+
+SECTIONS
+{
+    . = BASE_ADDRESS;
+    skernel = .;
+
+    stext = .;
+    .text : {
+        *(.text.entry)
+        *(.text)
+    }
+
+    . = ALIGN(4K);
+    etext = .;
+    srodata = .;
+    .rodata : {
+        *(.rodata)
+    }
+
+    . = ALIGN(4K);
+    erodata = .;
+    sdata = .;
+    .data : {
+        *(.data)
+    }
+
+    . = ALIGN(4K);
+    edata = .;
+    sbss = .;
+    .bss : {
+        *(.bss)
+    }
+
+    . = ALIGN(4K);
+    ebss = .;
+    .stack : {
+        *(.bss.stack)
+    }
+
+    ekernel = .;
+
+    /DISCARD/ : {
+        *(.eh_frame)
+    }
+}

os/src/main.rs

@@ -1,5 +1,12 @@
 #![no_std]
 #![no_main]
+#![feature(global_asm)]
 
 mod lang_items;
 
+global_asm!(include_str!("entry.asm"));
+
+#[no_mangle]
+pub extern "C" fn rust_main() -> ! {
+    loop {}
+}