diff options
Diffstat (limited to 'qemu/roms/u-boot/doc/README.console')
| -rw-r--r-- | qemu/roms/u-boot/doc/README.console | 101 |
1 files changed, 0 insertions, 101 deletions
diff --git a/qemu/roms/u-boot/doc/README.console b/qemu/roms/u-boot/doc/README.console deleted file mode 100644 index aadf596a8..000000000 --- a/qemu/roms/u-boot/doc/README.console +++ /dev/null @@ -1,101 +0,0 @@ -/* - * (C) Copyright 2000 - * Paolo Scaffardi, AIRVENT SAM s.p.a - RIMINI(ITALY), arsenio@tin.it - * - * SPDX-License-Identifier: GPL-2.0+ - */ - -U-Boot console handling -======================== - -HOW THE CONSOLE WORKS? ----------------------- - -At system startup U-Boot initializes a serial console. When U-Boot -relocates itself to RAM, all console drivers are initialized (they -will register all detected console devices to the system for further -use). - -If not defined in the environment, the first input device is assigned -to the 'stdin' file, the first output one to 'stdout' and 'stderr'. - -You can use the command "coninfo" to see all registered console -devices and their flags. You can assign a standard file (stdin, -stdout or stderr) to any device you see in that list simply by -assigning its name to the corresponding environment variable. For -example: - - setenv stdin serial <- To use the serial input - setenv stdout video <- To use the video console - -Do a simple "saveenv" to save the console settings in the environment -and get them working on the next startup, too. - -HOW CAN I USE STANDARD FILE INTO THE SOURCES? ---------------------------------------------- - -You can use the following functions to access the console: - -* STDOUT: - putc (to put a char to stdout) - puts (to put a string to stdout) - printf (to format and put a string to stdout) - -* STDIN: - tstc (to test for the presence of a char in stdin) - getc (to get a char from stdin) - -* STDERR: - eputc (to put a char to stderr) - eputs (to put a string to stderr) - eprintf (to format and put a string to stderr) - -* FILE (can be 'stdin', 'stdout', 'stderr'): - fputc (like putc but redirected to a file) - fputs (like puts but redirected to a file) - fprintf (like printf but redirected to a file) - ftstc (like tstc but redirected to a file) - fgetc (like getc but redirected to a file) - -Remember that all FILE-related functions CANNOT be used before -U-Boot relocation (done in 'board_init_r' in arch/*/lib/board.c). - -HOW CAN I USE STANDARD FILE INTO APPLICATIONS? ----------------------------------------------- - -Use the 'bd_mon_fnc' field of the bd_t structure passed to the -application to do everything you want with the console. - -But REMEMBER that that will work only if you have not overwritten any -U-Boot code while loading (or uncompressing) the image of your -application. - -For example, you won't get the console stuff running in the Linux -kernel because the kernel overwrites U-Boot before running. Only -some parameters like the framebuffer descriptors are passed to the -kernel in the high memory area to let the applications (the kernel) -use the framebuffers initialized by U-Boot. - -SUPPORTED DRIVERS ------------------ - -Working drivers: - - serial (architecture dependent serial stuff) - video (mpc8xx video controller) - -Work in progress: - - wl_kbd (Wireless 4PPM keyboard) - -Waiting for volounteers: - - lcd (mpc8xx lcd controller; to ) - -TESTED CONFIGURATIONS ---------------------- - -The driver has been tested with the following configurations (see -CREDITS for other contact informations): - -- MPC823FADS with AD7176 on a PAL TV (YCbYCr) - arsenio@tin.it |