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@@ -2354,6 +2354,46 @@ format!) to the "bootm" command:
+More About U-Boot Image Types:
+U-Boot supports the following image types:
+ "Standalone Programs" are directly runnable in the environment
+ provided by U-Boot; it is expected that (if they behave
+ well) you can continue to work in U-Boot after return from
+ the Standalone Program.
+ "OS Kernel Images" are usually images of some Embedded OS which
+ will take over control completely. Usually these programs
+ will install their own set of exception handlers, device
+ drivers, set up the MMU, etc. - this means, that you cannot
+ expect to re-enter U-Boot except by resetting the CPU.
+ "RAMDisk Images" are more or less just data blocks, and their
+ parameters (address, size) are passed to an OS kernel that is
+ being started.
+ "Multi-File Images" contain several images, typically an OS
+ (Linux) kernel image and one or more data images like
+ RAMDisks. This construct is useful for instance when you want
+ to boot over the network using BOOTP etc., where the boot
+ server provides just a single image file, but you want to get
+ for instance an OS kernel and a RAMDisk image.
+ "Multi-File Images" start with a list of image sizes, each
+ image size (in bytes) specified by an "uint32_t" in network
+ byte order. This list is terminated by an "(uint32_t)0".
+ Immediately after the terminating 0 follow the images, one by
+ one, all aligned on "uint32_t" boundaries (size rounded up to
+ a multiple of 4 bytes).
+ "Firmware Images" are binary images containing firmware (like
+ U-Boot or FPGA images) which usually will be programmed to
+ flash memory.
+ "Script files" are command sequences that will be executed by
+ U-Boot's command interpreter; this feature is especially
+ useful when you configure U-Boot to use a real shell (hush)
+ as command interpreter.