arm: bcmbca: add bcm6856 SoC support under CONFIG_ARCH_BCMBCA

BCM6856 is a Broadcom B53 based PON Gateway SoC. It is part of the BCA
(Broadband Carrier Access origin) chipset family. Like other Broadband
SoC, this patch adds it under CONFIG_BCM6856 chip config and
CONFIG_ARCH_BCMBCA platform config.

This initial support includes a bare-bone implementation and dts with
CPU subsystem, memory and Broadcom uart. This SoC is supported in the
linux-next git repository so the dts and dtsi files are copied from
linux.

The u-boot image can be loaded from flash or network to the entry point
address in the memory and boot from there to the console.

Signed-off-by: William Zhang <william.zhang@broadcom.com>
Reviewed-by: Philippe Reynes <philippe.reynes@softathome.com>
diff --git a/configs/bcm96856_defconfig b/configs/bcm96856_defconfig
new file mode 100644
index 0000000..7e1c097
--- /dev/null
+++ b/configs/bcm96856_defconfig
@@ -0,0 +1,23 @@
+CONFIG_ARM=y
+CONFIG_COUNTER_FREQUENCY=50000000
+CONFIG_ARCH_BCMBCA=y
+CONFIG_SYS_TEXT_BASE=0x01000000
+CONFIG_SYS_MALLOC_LEN=0x2000000
+CONFIG_SYS_MALLOC_F_LEN=0x8000
+CONFIG_BCM6856=y
+CONFIG_TARGET_BCM96856=y
+CONFIG_NR_DRAM_BANKS=2
+CONFIG_DEFAULT_DEVICE_TREE="bcm96856"
+CONFIG_IDENT_STRING=" Broadcom BCM6856"
+CONFIG_SYS_LOAD_ADDR=0x01000000
+CONFIG_ENV_VARS_UBOOT_CONFIG=y
+CONFIG_HAS_CUSTOM_SYS_INIT_SP_ADDR=y
+CONFIG_CUSTOM_SYS_INIT_SP_ADDR=0x2000000
+CONFIG_OF_STDOUT_VIA_ALIAS=y
+CONFIG_DISPLAY_BOARDINFO_LATE=y
+CONFIG_HUSH_PARSER=y
+CONFIG_SYS_MAXARGS=64
+CONFIG_SYS_BOOTM_LEN=0x4000000
+CONFIG_CMD_CACHE=y
+CONFIG_OF_EMBED=y
+CONFIG_CLK=y