From df233e734fb70076c0434b242594476332208ee0 Mon Sep 17 00:00:00 2001 From: Stefan Roese Date: Fri, 9 Sep 2016 07:45:49 +0200 Subject: [PATCH] x86: conga-qeval20-qa3: Add README to explain the console UART options This patch adds a small README to explain the 2 defconfig files and its usage for the different console UART options. Signed-off-by: Stefan Roese Reviewed-by: Bin Meng Cc: Simon Glass --- board/congatec/conga-qeval20-qa3-e3845/README | 23 +++++++++++++++++++++++ 1 file changed, 23 insertions(+) create mode 100644 board/congatec/conga-qeval20-qa3-e3845/README diff --git a/board/congatec/conga-qeval20-qa3-e3845/README b/board/congatec/conga-qeval20-qa3-e3845/README new file mode 100644 index 0000000..98ff992 --- /dev/null +++ b/board/congatec/conga-qeval20-qa3-e3845/README @@ -0,0 +1,23 @@ +------------------------------ +U-Boot console UART selection: +------------------------------ + +The U-Boot port for this congatec board currently supports two different +configurations (defconfig files). The only difference is the UART that +is used as the U-Boot console UART. The default defconfig file: + +conga-qeval20-qa3-e3845_defconfig + +provides this console on the UART0 which is provided via a Winbond +Super-IO chip connected on the congatec Qseven 2.0 evaluation carrier +board (conga-QEVAL). This UART is the one provided with a SubD9 +connector on the mainboard (the low one). The 2nd defconfig file: + +conga-qeval20-qa3-e3845-internal-uart_defconfig + +provides the U-Boot console on the BayTrail internal legacy UART, +which is routed from the QSeven SoM to the X300 connector on the +baseboard. Here is called COM2. The baseboard already provides the +RS232 level shifters. So a TTL-USB UART adapter does not work in +this case. The signals need to get connected directly to the +RS232 level signals of the PC UART via some adapter cable.