J784S4 and AM69 Platforms
Introduction
The J784S4 SoC belongs to the K3 Multicore SoC architecture platform, providing advanced system integration in automotive, ADAS and industrial applications requiring AI at the network edge. This SoC extends the K3 Jacinto 7 family of SoCs with focus on raising performance and integration while providing interfaces, memory architecture and compute performance for multi-sensor, high concurrency applications.
The device is partitioned into three functional domains, each containing specific processing cores and peripherals:
- Wake-up (WKUP) domain
ARM Cortex-M4F processor, runs TI Foundational Security (TIFS)
- Microcontroller (MCU) domain
Dual core ARM Cortex-R5F processor, runs device management and SoC early boot
- MAIN domain
Two clusters of quad core 64-bit ARM Cortex-A72, runs HLOS
Dual core ARM Cortex-R5F processor used for RTOS applications
Four C7x DSPs used for Machine Learning applications.
More info can be found in TRM: http://www.ti.com/lit/zip/spruj52
Platform information:
Boot Flow
Below is the pictorial representation of boot flow:
On this platform, “TI Foundational Security” (TIFS) functions as the security enclave master. While “Device Manager” (DM), also known as the “TISCI server” in TI terminology, offers all the essential services.
As illustrated in the diagram above, R5 SPL manages power and clock services independently before handing over control to DM. The A72 or the C7x (Aux core) software components request TIFS/DM to handle security or device management services.
Sources
Das U-Boot
branch: masterTrusted Firmware-A (TF-A)
branch: masterOpen Portable Trusted Execution Environment (OP-TEE)
branch: masterTI Firmware (TIFS, DM, SYSFW)
branch: ti-linux-firmware
Note
The TI Firmware required for functionality of the system can be one of the following combination (see platform specific boot diagram for further information as to which component runs on which processor):
TIFS - TI Foundational Security Firmware - Consists of purely firmware meant to run on the security enclave.
DM - Device Management firmware also called TI System Control Interface server (TISCI Server) - This component purely plays the role of managing device resources such as power, clock, interrupts, dma etc. This firmware runs on a dedicated or multi-use microcontroller outside the security enclave.
OR
SYSFW - System firmware - consists of both TIFS and DM both running on the security enclave.
Build procedure
Setup the environment variables:
S/w Component |
Env Variable |
Description |
---|---|---|
All Software |
CC32 |
Cross compiler for ARMv7 (ARM 32bit), typically arm-linux-gnueabihf- |
All Software |
CC64 |
Cross compiler for ARMv8 (ARM 64bit), typically aarch64-linux-gnu- |
All Software |
LNX_FW_PATH |
Path to TI Linux firmware repository |
All Software |
TFA_PATH |
Path to source of Trusted Firmware-A |
All Software |
OPTEE_PATH |
Path to source of OP-TEE |
S/w Component |
Env Variable |
Description |
---|---|---|
U-Boot |
UBOOT_CFG_CORTEXR |
Defconfig for Cortex-R (Boot processor). |
U-Boot |
UBOOT_CFG_CORTEXA |
Defconfig for Cortex-A (MPU processor). |
Trusted Firmware-A |
TFA_BOARD |
Platform name used for building TF-A for Cortex-A Processor. |
Trusted Firmware-A |
TFA_EXTRA_ARGS |
Any extra arguments used for building TF-A. |
OP-TEE |
OPTEE_PLATFORM |
Platform name used for building OP-TEE for Cortex-A Processor. |
OP-TEE |
OPTEE_EXTRA_ARGS |
Any extra arguments used for building OP-TEE. |
Set the variables corresponding to this platform:
export CC32=arm-linux-gnueabihf-
export CC64=aarch64-linux-gnu-
export LNX_FW_PATH=path/to/ti-linux-firmware
export TFA_PATH=path/to/trusted-firmware-a
export OPTEE_PATH=path/to/optee_os
$ export UBOOT_CFG_CORTEXR=j784s4_evm_r5_defconfig
$ export UBOOT_CFG_CORTEXA=j784s4_evm_a72_defconfig
$ export TFA_BOARD=j784s4
$ export TFA_EXTRA_ARGS="K3_USART=0x8"
$ export OPTEE_PLATFORM=k3-j784s4
$ export OPTEE_EXTRA_ARGS="CFG_CONSOLE_UART=0x8"
Trusted Firmware-A
# inside trusted-firmware-a source
make CROSS_COMPILE=$CC64 ARCH=aarch64 PLAT=k3 SPD=opteed $TFA_EXTRA_ARGS \
TARGET_BOARD=$TFA_BOARD
OP-TEE
# inside optee_os source
make CROSS_COMPILE=$CC32 CROSS_COMPILE64=$CC64 CFG_ARM64_core=y $OPTEE_EXTRA_ARGS \
PLATFORM=$OPTEE_PLATFORM
U-Boot
3.1 R5
# inside u-boot source
make $UBOOT_CFG_CORTEXR
make CROSS_COMPILE=$CC32 BINMAN_INDIRS=$LNX_FW_PATH
3.2 A72
# inside u-boot source
make $UBOOT_CFG_CORTEXA
make CROSS_COMPILE=$CC64 BINMAN_INDIRS=$LNX_FW_PATH \
BL31=$TFA_PATH/build/k3/$TFA_BOARD/release/bl31.bin \
TEE=$OPTEE_PATH/out/arm-plat-k3/core/tee-raw.bin
Note
It is also possible to pick up a custom DM binary by adding TI_DM argument pointing to the file. If not provided, it defaults to picking up the DM binary from BINMAN_INDIRS. This is only applicable to devices that utilize split firmware.
Target Images
In order to boot we need tiboot3.bin, tispl.bin and u-boot.img. Each SoC variant (GP, HS-FS, HS-SE) requires a different source for these files.
Image formats
tiboot3.bin
tispl.bin
R5 Memory Map
Region |
Start Address |
End Address |
---|---|---|
SPL |
0x41c00000 |
0x41c40000 |
EMPTY |
0x41c40000 |
0x41c61f20 |
STACK |
0x41c65f20 |
0x41c61f20 |
Global data |
0x41c65f20 |
0x41c66000 |
Heap |
0x41c66000 |
0x41c76000 |
BSS |
0x41c76000 |
0x41c80000 |
DM DATA |
0x41c80000 |
0x41c84130 |
EMPTY |
0x41c84130 |
0x41cff9fc |
MCU Scratchpad |
0x41cff9fc |
0x41cffbfc |
ROM DATA |
0x41cffbfc |
0x41cfffff |
Switch Setting for Boot Mode
Boot Mode pins provide means to select the boot mode and options before the device is powered up. After every POR, they are the main source to populate the Boot Parameter Tables.
Boot Mode Pins for J784S4-EVM
The following tables show some common boot modes used on J784S4 EVM platform. More details can be found in the Technical Reference Manual: http://www.ti.com/lit/zip/spruj52 under the Boot Mode Pins section.
Switch Label |
SW11: 12345678 |
SW7: 12345678 |
---|---|---|
SD |
10000010 |
00000000 |
EMMC |
10000000 |
01000000 |
OSPI |
00000110 |
01000000 |
UART |
00000000 |
01110000 |
For SW7 and SW11, the switch state in the “ON” position = 1.
Boot Mode Pins for AM69-SK
The following table show some common boot modes used on AM69-SK platform. More details can be found in the User Guide for AM69-SK: https://www.ti.com/lit/ug/spruj70/spruj70.pdf under the Bootmode Settings section.
Switch Label |
SW2: 1234 |
---|---|
SD |
0000 |
EMMC |
0110 |
UART |
1010 |
For SW2, the switch state in the “ON” position = 1.
Debugging U-Boot
See Common Debugging environment - OpenOCD: for detailed setup information.
Warning
OpenOCD support since: September 2023 (git master)
Until the next stable release of OpenOCD is available in your development environment’s distribution, it might be necessary to build OpenOCD from the source.
Debugging U-Boot on J784S4-EVM and AM69-SK
Integrated JTAG adapter/dongle: The board has a micro-USB connector labelled XDS110 USB or JTAG. Connect a USB cable to the board to the mentioned port.
Note
There are multiple USB ports on a typical board, So, ensure you have read the user guide for the board and confirmed the silk screen label to ensure connecting to the correct port.
To start OpenOCD and connect to J784S4-EVM or AM69-SK board, use the following.
openocd -f board/ti_j784s4evm.cfg