From bc74163a46208d1f9af8bfd2d06859b62145ef56 Mon Sep 17 00:00:00 2001 From: Andreas Dannenberg Date: Thu, 15 Aug 2019 15:55:32 -0500 Subject: [PATCH] board: ti: am65x: Add UART boot procedure in README am65x ROM support booting over UART. And U-Boot built for am65x EVM supports UART boot as well. Add the UART boot procedure into the README also providing a corresponding example command sequence for execution on a host PC. Signed-off-by: Andreas Dannenberg --- board/ti/am65x/README | 32 ++++++++++++++++++++++++++++++++ 1 file changed, 32 insertions(+) diff --git a/board/ti/am65x/README b/board/ti/am65x/README index 16384e05ea..2e3fd9c4a8 100644 --- a/board/ti/am65x/README +++ b/board/ti/am65x/README @@ -261,3 +261,35 @@ To boot kernel from eMMC, use the following commands: => setenv mmcdev 0 => setenv bootpart 0 => boot + +UART: +----- +ROM supports booting from MCU_UART0 via X-Modem protocol. The entire UART-based +boot process up to U-Boot (proper) prompt goes through different stages and uses +different UART peripherals as follows: + + WHO | Loading WHAT | HW Module | Protocol +----------+---------------+-------------+------------ +Boot ROM | tiboot3.bin | MCU_UART0 | X-Modem(*) +R5 SPL | sysfw.itb | MCU_UART0 | Y-Modem(*) +R5 SPL | tispl.bin | MAIN_UART0 | Y-Modem +A53 SPL | u-boot.img | MAIN_UART0 | Y-Modem + +(*) Note that in addition to X/Y-Modem related protocol timeouts the DMSC + watchdog timeout of 3min (typ.) needs to be observed until System Firmware + is fully loaded (from sysfw.itb) and started. + +Example bash script sequence for running on a Linux host PC feeding all boot +artifacts needed to the device: + +MCU_DEV=/dev/ttyUSB1 +MAIN_DEV=/dev/ttyUSB0 + +stty -F $MCU_DEV 115200 cs8 -cstopb -parenb +stty -F $MAIN_DEV 115200 cs8 -cstopb -parenb + +sb --xmodem tiboot3.bin > $MCU_DEV < $MCU_DEV +sb --ymodem sysfw.itb > $MCU_DEV < $MCU_DEV +sb --ymodem tispl.bin > $MAIN_DEV < $MAIN_DEV +sleep 1 +sb --xmodem u-boot.img > $MAIN_DEV < $MAIN_DEV -- 2.39.5