4 About Those Six Commands in the U-Boot

Before starting the implementation for six commands in the U-Boot, you need to know where the items that need to be modified can be found within the SDK installation.

The U-Boot path:

/opt/ti-processor-sdk-linux-rt-am64xx-evm-08.02.00.14/board-support/U-Boot-2021.01+gitAUTOINC+44a87e3ab8-g44a87e3ab8

U-Boot dts is here:

/opt/ti-processor-sdk-linux-rt-am64xx-evm-08.02.00.14/board-support/U-Boot-2021.01+gitAUTOINC+44a87e3ab8-g44a87e3ab8/arch/arm/dts/k3-am642-evm.dts

U-Boot config is here:

/opt/ti-processor-sdk-linux-rt-am64xx-evm-08.02.00.14/board-support/U-Boot-2021.01+gitAUTOINC+44a87e3ab8-g44a87e3ab8/configs/am64x_evm_r5_defconfig

Check that the ESM module is set by default to “y” in the following U-Boot config:

CONFIG_ESM_K3=y

In the MCU Domain Supported Reset section in the AM64x/AM243x Technical Reference Manual, the MCU domain reset are supported as described below:

In this application note, the RTI watchdog reset is used, so choose the MCU ESM error reset. Make sure to set this enabled: CONFIG_ESM_K3.

• Power-On-Resets
  • MCU_PORz device pin
• Warm Resets
  • MCU_RESETz device pin
  • MCU domain software warm reset
  • MCU domain ESM error reset ←
  • DMSC-L cold reset
• Local Module Resets
  • MCU domain LPSC module local reset

How to start the test commands running from U-Boot prompt?

1. Power on the EVM.
2. Press “Space” key continuously until the console shows the U-Boot prompt.
3. Input those 6 cmds:

   mw.l 0x43009008 0x68EF3490 1
   mw.l 0x4300900C 0xD172BC5A 1
   mw.l 0x43008380 0x3 1
   mw.l 0xe0000a4 0xa 1
   mw.l 0xe000094 0x23 1
   mw.l 0xe000090 0xA98559DA 1

4. By setting the value of 0x23, you will see the EVM reboot after about approximately 12 seconds.

Figure 4-1 shows the results of the console log. After inputting the 6 cmd, the system will reboot again.