MIPS: add initial infrastructure for Broadcom MIPS SoCs

CFE checks CPU Thread in a different way (using register $22):
mfc0	t1, C0_BCM_CONFIG, 3 # $22
li	t2, CP0_CMT_TPID # (1 << 31)
and	t1, t2
bnez	t1, 2f	# if we are running on thread 1, skip init
nop

Signed-off-by: Álvaro Fernández Rojas <noltari@gmail.com>
Reviewed-by: Simon Glass <sjg@chromium.org>

include/configs/bmips_common.h

@@ -0,0 +1,23 @@
+/*
+ * Copyright (C) 2017 Álvaro Fernández Rojas <noltari@gmail.com>
+ *
+ * SPDX-License-Identifier:	GPL-2.0+
+ */
+
+#ifndef __CONFIG_BMIPS_COMMON_H
+#define __CONFIG_BMIPS_COMMON_H
+
+/* RAM */
+#define CONFIG_SYS_MEMTEST_START	0xa0000000
+#define CONFIG_SYS_MEMTEST_END		0xa2000000
+
+/* Memory usage */
+#define CONFIG_SYS_MAXARGS		24
+#define CONFIG_SYS_MALLOC_LEN		(1024 * 1024)
+#define CONFIG_SYS_BOOTPARAMS_LEN	(128 * 1024)
+#define CONFIG_SYS_CBSIZE		512
+
+/* U-Boot */
+#define CONFIG_SYS_MONITOR_BASE		CONFIG_SYS_TEXT_BASE
+
+#endif /* __CONFIG_BMIPS_COMMON_H */