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https://github.com/brain-hackers/u-boot-brain
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![]() This patch exports LCD info-query and bitmap-rendering functions to external apps. This patch is tested on a Seaboard. Because the LCD driver is not yet upstreamed, the test was done in a local downstream repo. Signed-off-by: Che-Liang Chiou <clchiou@chromium.org> |
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.. | ||
api_display.c | ||
api_net.c | ||
api_platform-arm.c | ||
api_platform-powerpc.c | ||
api_private.h | ||
api_storage.c | ||
api.c | ||
Makefile | ||
README |
U-Boot machine/arch independent API for external apps ===================================================== 1. Main assumptions - there is a single entry point (syscall) to the API - per current design the syscall is a C-callable function in the U-Boot text, which might evolve into a real syscall using machine exception trap once this initial version proves functional - the consumer app is responsible for producing appropriate context (call number and arguments) - upon entry, the syscall dispatches the call to other (existing) U-Boot functional areas like networking or storage operations - consumer application will recognize the API is available by searching a specified (assumed by convention) range of address space for the signature - the U-Boot integral part of the API is meant to be thin and non-intrusive, leaving as much processing as possible on the consumer application side, for example it doesn't keep states, but relies on hints from the app and so on - optional (CONFIG_API) 2. Calls - console related (getc, putc, tstc etc.) - system (reset, platform info) - time (delay, current) - env vars (enumerate all, get, set) - devices (enumerate all, open, close, read, write); currently two classes of devices are recognized and supported: network and storage (ide, scsi, usb etc.) 3. Structure overview - core API, integral part of U-Boot, mandatory - implements the single entry point (mimics UNIX syscall) - glue - entry point at the consumer side, allows to make syscall, mandatory part - helper conveniency wrappers so that consumer app does not have to use the syscall directly, but in a more friendly manner (a la libc calls), optional part - consumer application - calls directly, or leverages the provided glue mid-layer