build system and some other stuff

1 files changed, 39 insertions, 0 deletions

diff --git a/sys/kern/entry.S b/sys/kern/entry.S
new file mode 100644
index 0000000..5ad0490
--- /dev/null
+++ b/sys/kern/entry.S
@@ -0,0 +1,39 @@
+.section ".text.init"
+
+.globl _start
+_start:
+        csrw       satp, zero
+        csrw       sie, zero
+        csrw       sip, zero
+
+        .option push
+        .option norelax
+        la         gp, __global_pointer$
+        .option pop
+
+        la         sp, __stack_start
+        li         t1, PAGE_SIZE 
+        mul        t1, t1, a0
+        add        sp, sp, t1
+
+        li         a2, 1
+        lla        a3, _boot_hart
+        amoswap.w  a3, a2, (a3)
+        bnez a3,   _spin
+
+        la         a2, __bss_start
+        la         a3, __bss_end
+1:
+        sd	   zero, (a2)
+        addi       a2, a2, __SIZEOF_POINTER__
+        blt        a2, a3, 1b 
+        
+        call       init
+
+
+_spin:
+	wfi
+	j _spin
+
+.section ".data"
+_boot_hart: .word 0