diff --git a/arch/arm/asm.S b/arch/arm/asm.S
new file mode 100644
index 0000000..2953bd6
--- /dev/null
+++ b/arch/arm/asm.S
@@ -0,0 +1,88 @@
+/*
+ * Copyright (c) 2008 Travis Geiselbrecht
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining
+ * a copy of this software and associated documentation files
+ * (the "Software"), to deal in the Software without restriction,
+ * including without limitation the rights to use, copy, modify, merge,
+ * publish, distribute, sublicense, and/or sell copies of the Software,
+ * and to permit persons to whom the Software is furnished to do so,
+ * subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be
+ * included in all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
+ * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
+ * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.
+ * IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY
+ * CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT,
+ * TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE
+ * SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
+ */
+#include <asm.h>
+
+
+	/* context switch frame is as follows:
+	 * ulr
+	 * usp
+	 * lr
+	 * r11
+	 * r10
+	 * r9
+	 * r8
+	 * r7
+	 * r6
+	 * r5
+	 * r4
+	 */
+/* arm_context_switch(addr_t *old_sp, addr_t new_sp) */
+FUNCTION(arm_context_switch)
+	/* save all the usual registers + user regs */
+	/* the spsr is saved and restored in the iframe by exceptions.S */
+	sub		r3, sp, #(11*4)		/* can't use sp in user mode stm */
+	mov		r12, lr
+	stmia	r3, { r4-r11, r12, r13, r14 }^
+	
+	/* save old sp */
+	str		r3, [r0] 
+
+	/* load new regs */
+	ldmia	r1, { r4-r11, r12, r13, r14 }^
+	mov		lr, r12				/* restore lr */
+	add		sp, r1, #(11*4)     /* restore sp */
+	bx		lr
+
+FUNCTION(arm_save_mode_regs)
+	mrs		r1, cpsr
+
+#if ARM_ISA_ARMv6
+	cps		#0x11			/* fiq */
+	str		r13, [r0], #4
+	str		r14, [r0], #4
+	cps		#0x12			/* irq */
+	str		r13, [r0], #4
+	str		r14, [r0], #4
+	cps		#0x13			/* svc */
+	str		r13, [r0], #4
+	str		r14, [r0], #4
+	cps		#0x17			/* abt */
+	str		r13, [r0], #4
+	str		r14, [r0], #4
+	cps		#0x1b			/* und */
+	str		r13, [r0], #4
+	str		r14, [r0], #4
+	cps		#0x1f			/* sys */
+	str		r13, [r0], #4
+	str		r14, [r0], #4
+#else
+	// XXX implement
+	b		.
+#endif
+	
+	msr		cpsr, r1
+
+	bx		lr
+
+	
+