xref: /openbmc/u-boot/doc/README.splashprepare (revision 66dae3bb)
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2Splash Screen
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4The splash_screen_prepare() function is a weak function defined in
5common/splash.c. It is called as part of the splash screen display
6sequence. It gives the board an opportunity to prepare the splash
7image data before it is processed and sent to the frame buffer by
8U-Boot. Define your own version to use this feature.
9
10CONFIG_SPLASH_SOURCE
11
12Use the splash_source.c library. This library provides facilities to declare
13board specific splash image locations, routines for loading splash image from
14supported locations, and a way of controlling the selected splash location
15using the "splashsource" environment variable.
16
17splashsource works as follows:
18- If splashsource is set to a supported location name as defined by board code,
19  use that splash location.
20- If splashsource is undefined, use the first splash location as default.
21- If splashsource is set to an unsupported value, do not load a splash screen.
22
23A splash source location can describe either storage with raw data, a storage
24formatted with a file system or a FIT image. In case of a filesystem, the splash
25screen data is loaded as a file. The name of the splash screen file can be
26controlled with the environment variable "splashfile".
27
28To enable loading the splash image from a FIT image, CONFIG_FIT must be
29enabled. Struct splash_location field 'name' should match the splash image
30name within the FIT and the FIT should start at the 'offset' field address in
31the specified storage.
32