Initial raspberry Pi 2 support.

 * Support for interrupt controller.
 * Simple "bootloader" code.
 * Some changes to attach agtimer/pl011.
 * Disable pl011 FIFO.

TODO:
 * debugging

sys/arch/armv7/armv7/rpi.S

@@ -0,0 +1,34 @@
+/*
+ * Copyright (c) 2015 Patrick Wildt <patrick@blueri.se>
+ *
+ * Permission to use, copy, modify, and distribute this software for any
+ * purpose with or without fee is hereby granted, provided that the above
+ * copyright notice and this permission notice appear in all copies.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
+ * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
+ * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
+ * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
+ * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
+ * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
+ * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
+ */
+
+#include <machine/asm.h>
+
+	.text
+
+	.global	_C_LABEL(rpi_entry)
+_C_LABEL(rpi_entry):
+	b	jump
+	mov	r0, r0
+	mov	r0, r0
+	mov	r0, r0
+	mov	r0, r0
+	mov	r0, r0
+	mov	r0, r0
+	mov	r0, r0
+jump:
+	ldr	pc, [pc]
+	mov	r0, r0
+	.word	0x00300000