initial import of armv8-hello

2025-05-22 02:43:17 +00:00 · 2016-01-05 13:27:51 +08:00
commit 89bacd7f88
8 changed files with 159 additions and 0 deletions
@@ -0,0 +1,29 @@
+#include "reg.h"
+
+.text
+
+.globl	_start
+_start:
+	/* init UART (38400 8N1) */
+	ldr	x4, =UART_BASE		// UART base
+	mov	w5, #0x10		// IBRD
+	str	w5, [x4, #0x24]
+	mov	w5, #0xc300
+	orr	w5, w5, #0x0001		// CR
+	str	w5, [x4, #0x30]
+
+	/* check CPU ID */
+	mrs x0, mpidr_el1
+	tst x0, #15
+	b.ne    other_cpu
+	b.eq	boot_cpu
+
+boot_cpu:
+	/* configure stack */
+	adrp x0, stacktop
+	mov sp, x0
+
+	b main
+
+other_cpu:
+	b other_cpu