Move bss initialization to C code

3 files changed, 10 insertions, 10 deletions

diff --git a/src/common.h b/src/common.h
index 0057950..c71455d 100644
--- a/src/common.h
+++ b/src/common.h
@@ -23,7 +23,7 @@
 void delay(u64 ticks);
 
 // Clear N bytes at the given address 8 bytes at a time. Implemented in start.s.
-void memzero64(void * src, u32 n);
+void memzero64(void *src, u64 n);
 
 //
 // GPIO Registers.
diff --git a/src/main.c b/src/main.c
index 1853192..8ab3cf5 100644
--- a/src/main.c
+++ b/src/main.c
@@ -126,8 +126,6 @@ file_talk(Device *d, u8 b0, u8 w) {
 
 void
 init_uxn() {
-    uart_init();
-
     uart_puts("Initializing UXN.\n");
 
     // Clear UXN memory.
@@ -162,8 +160,16 @@ init_uxn() {
     mempoke16(devscreen->dat, 4, ppu.height);
 }
 
+void
+clear_bss(void) {
+    extern u64 __bss_start;
+    extern u64 __bss_end;
+    memzero64(&__bss_start, &__bss_end - &__bss_start);
+}
+
 void main(void) {
-    // Initialize uart.
+    clear_bss();
+    uart_init();
     init_uxn();
 
     uxn_eval(&u, 0x0100);
diff --git a/src/start.s b/src/start.s
index ecedeb4..b6a6d0f 100644
--- a/src/start.s
+++ b/src/start.s
@@ -29,12 +29,6 @@ master:
     ldr     x0, =__stack_end
     mov     sp, x0
 
-    // Clear .bss memory.
-    ldr     x0, =__bss_start
-    ldr     x1, =__bss_end
-    sub     x1, x1, x0
-    bl      memzero64
-
     // Start C code, should not return.
     bl      main
     b       halt