create support for kernel modules (but don't implement them yet)

1 files changed, 20 insertions, 0 deletions

diff --git a/kernel/start.S b/kernel/start.S
new file mode 100644
index 0000000..dce0faa
--- /dev/null
+++ b/kernel/start.S
@@ -0,0 +1,20 @@
+.section .text._start
+.global _start
+.type _start, @function
+
+_start:
+    csrw mstatus, zero
+    csrw mie, zero
+    
+    la sp, __stack_top
+    
+    la t0, __bss_start
+    la t1, __bss_end
+    beq t0, t1, 2f
+1:
+    sw zero, 0(t0)
+    addi t0, t0, 4
+    bltu t0, t1, 1b
+2:
+    call kernel_main
+    j .