From 3f2546b2ef55b661fd8dd69682b38992225e86f6 Mon Sep 17 00:00:00 2001 From: fishsoupisgood Date: Mon, 29 Apr 2019 01:17:54 +0100 Subject: Initial import of qemu-2.4.1 --- roms/u-boot/doc/README.serial_multi | 80 +++++++++++++++++++++++++++++++++++++ 1 file changed, 80 insertions(+) create mode 100644 roms/u-boot/doc/README.serial_multi (limited to 'roms/u-boot/doc/README.serial_multi') diff --git a/roms/u-boot/doc/README.serial_multi b/roms/u-boot/doc/README.serial_multi new file mode 100644 index 00000000..ad61d426 --- /dev/null +++ b/roms/u-boot/doc/README.serial_multi @@ -0,0 +1,80 @@ +The support for multiple serial interfaces as implemented is mainly +intended to allow for modem dial-in / dial-out while still being able +to use a serial console on a (different) serial port. + +MPC8XX Specific +=============== +At the moment, the ports must be split on a SMC and a SCC port on a +8xx processor; other configurations are not (yet) supported. + +Support for hardware handshake has not been implemented yet (but is +in the works). + +*) The default console depends on the keys pressed: + - SMC if keys not pressed (modem not enabled) + - SCC if keys pressed (modem enabled) + +*) The console can be switched to SCC by any of the following commands: + + setenv stdout serial_scc + setenv stdin serial_scc + setenv stderr serial_scc + +*) The console can be switched to SMC by any of the following commands: + + setenv stdout serial_smc + setenv stdin serial_smc + setenv stderr serial_smc + +*) If a file descriptor is set to "serial" then the current serial device +will be used which, in turn, can be switched by above commands. + +*) The baudrate is the same for all serial devices. But it can be switched +just after switching the console: + + setenv sout serial_scc; setenv baudrate 38400 + +After that press 'enter' at the SCC console. Note that baudrates <38400 +are not allowed on LWMON with watchdog enabled (see CONFIG_SYS_BAUDRATE_TABLE in +include/configs/lwmon.h). + + +PPC4XX Specific +=============== +*) The default console is UART0 + +*) The console can be switched to UART1 by any of the following commands: + setenv stdout serial1 + setenv stderr serial1 + setenv stdin serial1 + +*) The console can be switched to UART0 by any of the following commands: + setenv stdout serial0 + setenv stderr serial0 + setenv stdin serial0 + +MPC5xxx Specific +================ + +Up to two PSCs can be used as console. + +Support for hardware handshake has not been implemented yet. + +*) The first (default) console port is defined by: + #define CONFIG_PSC_CONSOLE + +*) The second (alternative) console port is defined by: + #define CONFIG_PSC_CONSOLE2 + +*) Commands to switch to the second console: + setenv stdout serial1 + setenv stderr serial1 + setenv stdin serial1 + +*) Commands to switch to the first console: + setenv stdout serial0 + setenv stderr serial0 + setenv stdin serial0 + +*) If a file descriptor is set to "serial" then the + current serial device will be used. -- cgit v1.2.3