| Introduction: |
| ------------- |
| The AM65x family of SoCs is the first device family from K3 Multicore |
| SoC architecture, targeted for broad market and industrial control with |
| aim to meet the complex processing needs of modern embedded products. |
| |
| The device is built over three domains, each containing specific processing |
| cores, voltage domains and peripherals: |
| 1. Wake-up (WKUP) domain: |
| - Device Management and Security Controller (DMSC) |
| 2. Microcontroller (MCU) domain: |
| - Dual Core ARM Cortex-R5F processor |
| 3. MAIN domain: |
| - Quad core 64-bit ARM Cortex-A53 |
| |
| More info can be found in TRM: http://www.ti.com/lit/pdf/spruid7 |
| |
| Boot Flow: |
| ---------- |
| On AM65x family devices, ROM supports boot only via MCU(R5). This means that |
| bootloader has to run on R5 core. In order to meet this constraint, and for |
| the following reasons the boot flow is designed as mentioned: |
| 1. Need to move away from R5 asap, so that we want to start *any* |
| firmware on the r5 cores like.... autosar can be loaded to receive CAN |
| response and other safety operations to be started. This operation is |
| very time critical and is applicable for all automotive use cases. |
| 2. U-Boot on A53 should start other remotecores for various |
| applications. This should happen before running Linux. |
| 3. In production boot flow, we might not like to use full u-boot, |
| instead use Flacon boot flow to reduce boot time. |
| |
| +------------------------------------------------------------------------+ |
| | DMSC | R5 | A53 | |
| +------------------------------------------------------------------------+ |
| | +--------+ | | | |
| | | Reset | | | | |
| | +--------+ | | | |
| | : | | | |
| | +--------+ | +-----------+ | | |
| | | *ROM* |----------|-->| Reset rls | | | |
| | +--------+ | +-----------+ | | |
| | | | | : | | |
| | | ROM | | : | | |
| | |services| | : | | |
| | | | | +-------------+ | | |
| | | | | | *R5 ROM* | | | |
| | | | | +-------------+ | | |
| | | |<---------|---|Load and auth| | | |
| | | | | | tiboot3.bin | | | |
| | | | | +-------------+ | | |
| | | | | : | | |
| | | | | : | | |
| | | | | : | | |
| | | | | +-------------+ | | |
| | | | | | *R5 SPL* | | | |
| | | | | +-------------+ | | |
| | | | | | Load | | | |
| | | | | | sysfw.itb | | | |
| | | Start | | +-------------+ | | |
| | | System |<---------|---| Start | | | |
| | |Firmware| | | SYSFW | | | |
| | +--------+ | +-------------+ | | |
| | : | | | | | |
| | +---------+ | | Load | | | |
| | | *SYSFW* | | | system | | | |
| | +---------+ | | Config data | | | |
| | | |<--------|---| | | | |
| | | | | +-------------+ | | |
| | | | | | | | | |
| | | | | | DDR | | | |
| | | | | | config | | | |
| | | | | +-------------+ | | |
| | | | | | | | | |
| | | |<--------|---| Start A53 | | | |
| | | | | | and Reset | | | |
| | | | | +-------------+ | | |
| | | | | | +-----------+ | |
| | | |---------|-----------------------|---->| Reset rls | | |
| | | | | | +-----------+ | |
| | | DMSC | | | : | |
| | |Services | | | +-----------+ | |
| | | |<--------|-----------------------|---->|*ATF/OPTEE*| | |
| | | | | | +-----------+ | |
| | | | | | : | |
| | | | | | +-----------+ | |
| | | |<--------|-----------------------|---->| *A53 SPL* | | |
| | | | | | +-----------+ | |
| | | | | | | Load | | |
| | | | | | | u-boot.img| | |
| | | | | | +-----------+ | |
| | | | | | : | |
| | | | | | +-----------+ | |
| | | |<--------|-----------------------|---->| *U-Boot* | | |
| | | | | | +-----------+ | |
| | | | | | | prompt | | |
| | | | | | +-----------+ | |
| | +---------+ | | | |
| | | | | |
| +------------------------------------------------------------------------+ |
| |
| - Here DMSC acts as master and provides all the critical services. R5/A53 |
| requests DMSC to get these services done as shown in the above diagram. |
| |
| Sources: |
| -------- |
| 1. SYSFW: |
| Tree: git://git.ti.com/processor-firmware/system-firmware-image-gen.git |
| Branch: master |
| |
| 2. ATF: |
| Tree: https://github.com/ARM-software/arm-trusted-firmware.git |
| Branch: master |
| |
| 3. OPTEE: |
| Tree: https://github.com/OP-TEE/optee_os.git |
| Branch: master |
| |
| 4. U-Boot: |
| Tree: http://git.denx.de/u-boot.git |
| Branch: master |
| |
| Build procedure: |
| ---------------- |
| 1. SYSFW: |
| $ make CROSS_COMPILE=arm-linux-gnueabihf- |
| |
| 2. ATF: |
| $ make CROSS_COMPILE=aarch64-linux-gnu- ARCH=aarch64 PLAT=k3 TARGET_BOARD=generic SPD=opteed |
| |
| 3. OPTEE: |
| $ make PLATFORM=k3-am65x CFG_ARM64_core=y |
| |
| 4. U-Boot: |
| |
| 4.1. R5: |
| $ make ARCH=arm CROSS_COMPILE=arm-linux-gnueabihf- am65x_evm_r5_defconfig O=/tmp/r5 |
| $ make ARCH=arm CROSS_COMPILE=arm-linux-gnueabihf- O=/tmp/r5 |
| |
| 4.2. A53: |
| $ make ARCH=arm CROSS_COMPILE=aarch64-linux-gnu- am65x_evm_a53_defconfig O=/tmp/a53 |
| $ make ARCH=arm CROSS_COMPILE=aarch64-linux-gnu- ATF=<path to ATF dir>/build/k3/generic/release/bl31.bin TEE=<path to OPTEE OS dir>/out/arm-plat-k3/core/tee-pager.bin O=/tmp/a53 |
| |
| Target Images |
| -------------- |
| Copy the below images to an SD card and boot: |
| - sysfw.itb from step 1 |
| - tiboot3.bin from step 4.1 |
| - tispl.bin, u-boot.img from 4.2 |
| |
| Image formats: |
| -------------- |
| |
| - tiboot3.bin: |
| +-----------------------+ |
| | X.509 | |
| | Certificate | |
| | +-------------------+ | |
| | | | | |
| | | R5 | | |
| | | u-boot-spl.bin | | |
| | | | | |
| | +-------------------+ | |
| | | | | |
| | | FIT header | | |
| | | +---------------+ | | |
| | | | | | | |
| | | | DTB 1...N | | | |
| | | +---------------+ | | |
| | +-------------------+ | |
| +-----------------------+ |
| |
| - tispl.bin |
| +-----------------------+ |
| | | |
| | FIT HEADER | |
| | +-------------------+ | |
| | | | | |
| | | A53 ATF | | |
| | +-------------------+ | |
| | | | | |
| | | A53 OPTEE | | |
| | +-------------------+ | |
| | | | | |
| | | A53 SPL | | |
| | +-------------------+ | |
| | | | | |
| | | SPL DTB 1...N | | |
| | +-------------------+ | |
| +-----------------------+ |
| |
| - sysfw.itb |
| +-----------------------+ |
| | | |
| | FIT HEADER | |
| | +-------------------+ | |
| | | | | |
| | | sysfw.bin | | |
| | +-------------------+ | |
| | | | | |
| | | board config | | |
| | +-------------------+ | |
| | | | | |
| | | PM config | | |
| | +-------------------+ | |
| | | | | |
| | | RM config | | |
| | +-------------------+ | |
| | | | | |
| | | Secure config | | |
| | +-------------------+ | |
| +-----------------------+ |
| |
| eMMC: |
| ----- |
| ROM supports booting from eMMC from boot0 partition offset 0x0 |
| |
| Flashing images to eMMC: |
| |
| The following commands can be used to download tiboot3.bin, tispl.bin, |
| u-boot.img, and sysfw.itb from an SD card and write them to the eMMC boot0 |
| partition at respective addresses. |
| |
| => mmc dev 0 1 |
| => fatload mmc 1 ${loadaddr} tiboot3.bin |
| => mmc write ${loadaddr} 0x0 0x400 |
| => fatload mmc 1 ${loadaddr} tispl.bin |
| => mmc write ${loadaddr} 0x400 0x1000 |
| => fatload mmc 1 ${loadaddr} u-boot.img |
| => mmc write ${loadaddr} 0x1400 0x2000 |
| => fatload mmc 1 ${loadaddr} sysfw.itb |
| => mmc write ${loadaddr} 0x3600 0x800 |
| |
| To give the ROM access to the boot partition, the following commands must be |
| used for the first time: |
| => mmc partconf 0 1 1 1 |
| => mmc bootbus 0 1 0 0 |
| |
| To create a software partition for the rootfs, the following command can be |
| used: |
| => gpt write mmc 0 ${partitions} |
| |
| eMMC layout: |
| |
| boot0 partition (8 MB) user partition |
| 0x0+----------------------------------+ 0x0+-------------------------+ |
| | tiboot3.bin (512 KB) | | | |
| 0x400+----------------------------------+ | | |
| | tispl.bin (2 MB) | | | |
| 0x1400+----------------------------------+ | rootfs | |
| | u-boot.img (4 MB) | | | |
| 0x3400+----------------------------------+ | | |
| | environment (128 KB) | | | |
| 0x3500+----------------------------------+ | | |
| | backup environment (128 KB) | | | |
| 0x3600+----------------------------------+ | | |
| | sysfw (1 MB) | | | |
| 0x3E00+----------------------------------+ +-------------------------+ |
| |
| Kernel image and DT are expected to be present in the /boot folder of rootfs. |
| To boot kernel from eMMC, use the following commands: |
| => setenv mmcdev 0 |
| => setenv bootpart 0 |
| => boot |
