MIPS: JZ4740: require & include DT

Require a DT for JZ4740 based systems, and add a stub one for the
qi_lb60 (Ben NanoNote) board. Devices will be migrated to being probed
via this DT over time.
Signed-off-by: Paul Burton <paul.burton@imgtec.com>
Cc: Ian Campbell <ijc+devicetree@hellion.org.uk>
Cc: Kumar Gala <galak@codeaurora.org>
Cc: Lars-Peter Clausen <lars@metafoo.de>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Pawel Moll <pawel.moll@arm.com>
Cc: Rob Herring <robh+dt@kernel.org>
Cc: devicetree@vger.kernel.org
Cc: linux-mips@linux-mips.org
Cc: Andrew Bresticker <abrestic@chromium.org>
Cc: linux-kernel@vger.kernel.org
Patchwork: https://patchwork.linux-mips.org/patch/10132/Signed-off-by: Ralf Baechle <ralf@linux-mips.org>

arch/mips/Kconfig

@@ -300,6 +300,8 @@ config MACH_INGENIC
 	select SYS_HAS_EARLY_PRINTK
 	select HAVE_CLK
 	select GENERIC_IRQ_CHIP
+	select BUILTIN_DTB
+	select USE_OF
 
 config LANTIQ
 	bool "Lantiq based platforms"

arch/mips/boot/dts/Makefile

 dts-dirs	+= brcm
 dts-dirs	+= cavium-octeon
+dts-dirs	+= ingenic
 dts-dirs	+= lantiq
 dts-dirs	+= mti
 dts-dirs	+= netlogic

arch/mips/boot/dts/ingenic/Makefile

+dtb-$(CONFIG_JZ4740_QI_LB60)	+= qi_lb60.dtb
+
+obj-y				+= $(patsubst %.dtb, %.dtb.o, $(dtb-y))
+
+# Force kbuild to make empty built-in.o if necessary
+obj-				+= dummy.o
+
+always				:= $(dtb-y)
+clean-files			:= *.dtb *.dtb.S

arch/mips/boot/dts/ingenic/jz4740.dtsi

+/ {
+	#address-cells = <1>;
+	#size-cells = <1>;
+	compatible = "ingenic,jz4740";
+};

arch/mips/boot/dts/ingenic/qi_lb60.dts

+/dts-v1/;
+
+#include "jz4740.dtsi"
+
+/ {
+	compatible = "qi,lb60", "ingenic,jz4740";
+};

arch/mips/jz4740/setup.c

@@ -17,8 +17,11 @@
 #include <linux/init.h>
 #include <linux/io.h>
 #include <linux/kernel.h>
+#include <linux/of_fdt.h>
+#include <linux/of_platform.h>
 
 #include <asm/bootinfo.h>
+#include <asm/prom.h>
 
 #include <asm/mach-jz4740/base.h>
 
@@ -53,8 +56,24 @@ void __init plat_mem_setup(void)
 {
 	jz4740_reset_init();
 	jz4740_detect_mem();
+	__dt_setup_arch(__dtb_start);
 }
 
+void __init device_tree_init(void)
+{
+	if (!initial_boot_params)
+		return;
+
+	unflatten_and_copy_device_tree();
+}
+
+static int __init populate_machine(void)
+{
+	of_platform_populate(NULL, of_default_bus_match_table, NULL, NULL);
+	return 0;
+}
+arch_initcall(populate_machine);
+
 const char *get_system_type(void)
 {
 	return "JZ4740";