SPL: FIT: allow loading multiple images

So far we were not using the FIT image format to its full potential:
The SPL FIT loader was just loading the first image from the /images
node plus one of the listed DTBs.
Now with the refactored loader code it's easy to load an arbitrary
number of images in addition to the two mentioned above.
As described in the FIT image source file format description, iterate
over all images listed at the "loadables" property in the configuration
node and load every image at its desired location.
This allows to load any kind of images:
- firmware images to execute before U-Boot proper (for instance
  ARM Trusted Firmware (ATF))
- firmware images for management processors (SCP, arisc, ...)
- firmware images for devices like WiFi controllers
- bit files for FPGAs
- additional configuration data
- kernels and/or ramdisks
The actual usage of this feature would be platform and/or board specific.

Also update the FIT documentation to mention the new SPL feature and
provide an example .its file to demonstrate its features.

Signed-off-by: Andre Przywara <andre.przywara@arm.com>
Reviewed-by: Lokesh Vutla <lokeshvuta@ti.com>
Reviewed-by: Simon Glass <sjg@chromium.org>
Tested-by: Heiko Stuebner <heiko@sntech.de>
Reviewed-by: Kever Yang <kever.yang@rock-chips.com>
Tested-by: Kever Yang <kever.yang@rock-chips.com>
Tested-by: Jagan Teki <jagan@openedev.com>
Reviewed-by: Jagan Teki <jagan@openedev.com>

1 files changed, 89 insertions, 0 deletions

diff --git a/doc/uImage.FIT/multi_spl.its b/doc/uImage.FIT/multi_spl.its
new file mode 100644
index 00000000000..e5551d42b70
--- /dev/null
+++ b/doc/uImage.FIT/multi_spl.its
@@ -0,0 +1,89 @@
+/dts-v1/;
+
+/*
+ * (Bogus) example FIT image description file demonstrating the usage
+ * of multiple images loaded by the SPL.
+ * Several binaries will be loaded at their respective load addresses.
+ * Finally the one image specifying an entry point will be entered by the SPL.
+ */
+
+/ {
+	description = "multiple firmware blobs and U-Boot, loaded by SPL";
+	#address-cells = <0x1>;
+
+	images {
+
+		uboot {
+			description = "U-Boot (64-bit)";
+			type = "standalone";
+			arch = "arm64";
+			compression = "none";
+			load = <0x4a000000>;
+		};
+
+		atf {
+			description = "ARM Trusted Firmware";
+			type = "firmware";
+			arch = "arm64";
+			compression = "none";
+			load = <0x18000>;
+			entry = <0x18000>;
+		};
+
+		mgmt-firmware {
+			description = "arisc management processor firmware";
+			type = "firmware";
+			arch = "or1k";
+			compression = "none";
+			load = <0x40000>;
+		};
+
+		fdt@1 {
+			description = "Pine64+ DT";
+			type = "flat_dt";
+			compression = "none";
+			load = <0x4fa00000>;
+			arch = "arm64";
+		};
+
+		fdt@2 {
+			description = "Pine64 DT";
+			type = "flat_dt";
+			compression = "none";
+			load = <0x4fa00000>;
+			arch = "arm64";
+		};
+
+		kernel {
+			description = "4.7-rc5 kernel";
+			type = "kernel";
+			compression = "none";
+			load = <0x40080000>;
+			arch = "arm64";
+		};
+
+		initrd {
+			description = "Debian installer initrd";
+			type = "ramdisk";
+			compression = "none";
+			load = <0x4fe00000>;
+			arch = "arm64";
+		};
+	};
+
+	configurations {
+		default = "config@1";
+
+		config@1 {
+			description = "sun50i-a64-pine64-plus";
+			loadables = "uboot", "atf", "kernel", "initrd";
+			fdt = "fdt@1";
+		};
+
+		config@2 {
+			description = "sun50i-a64-pine64";
+			loadables = "uboot", "atf", "mgmt-firmware";
+			fdt = "fdt@2";
+		};
+	};
+};