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@@ -638,6 +638,23 @@ The following options need to be configured:
'Sane' compilers will generate smaller code if
CONFIG_PRE_CON_BUF_SZ is a power of 2
+- Pre-console putc():
+ Prior to the console being initialised, console output is
+ normally silently discarded. This can be annoying if a
+ panic() happens in this time.
+
+ If the CONFIG_PRE_CONSOLE_PUTC option is defined, then
+ U-Boot will call board_pre_console_putc() for each output
+ character in this case, This function should try to output
+ the character if possible, perhaps on all available UARTs
+ (it will need to do this directly, since the console code
+ is not functional yet). Note that if the panic happens
+ early enough, then it is possible that board_init_f()
+ (or even arch_cpu_init() on ARM) has not been called yet.
+ You should init all clocks, GPIOs, etc. that are needed
+ to get the character out. Baud rates will need to default
+ to something sensible.
+
- Boot Delay: CONFIG_BOOTDELAY - in seconds
Delay before automatically booting the default image;
set to -1 to disable autoboot.