blob: 98ff992a3d3d9f8ab6541edd0318589198ae8b21 [file] [log] [blame]
Stefan Roesedf233e72016-09-09 07:45:49 +02001------------------------------
2U-Boot console UART selection:
3------------------------------
4
5The U-Boot port for this congatec board currently supports two different
6configurations (defconfig files). The only difference is the UART that
7is used as the U-Boot console UART. The default defconfig file:
8
9conga-qeval20-qa3-e3845_defconfig
10
11provides this console on the UART0 which is provided via a Winbond
12Super-IO chip connected on the congatec Qseven 2.0 evaluation carrier
13board (conga-QEVAL). This UART is the one provided with a SubD9
14connector on the mainboard (the low one). The 2nd defconfig file:
15
16conga-qeval20-qa3-e3845-internal-uart_defconfig
17
18provides the U-Boot console on the BayTrail internal legacy UART,
19which is routed from the QSeven SoM to the X300 connector on the
20baseboard. Here is called COM2. The baseboard already provides the
21RS232 level shifters. So a TTL-USB UART adapter does not work in
22this case. The signals need to get connected directly to the
23RS232 level signals of the PC UART via some adapter cable.