board: j721e: Add README
Add README file explaining the build and boot procedure for J721E evm.
Signed-off-by: Lokesh Vutla <lokeshvutla@ti.com>
diff --git a/board/ti/j721e/README b/board/ti/j721e/README
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+Introduction:
+-------------
+The J721e family of SoCs are part of K3 Multicore SoC architecture platform
+targeting automotive applications. They are designed as a low power, high
+performance and highly integrated device architecture, adding significant
+enhancement on processing power, graphics capability, video and imaging
+processing, virtualization and coherent memory support.
+
+The device is partitioned into three functional domains, each containing
+specific processing cores 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:
+ - Dual core 64-bit ARM Cortex-A72
+ - 2 x Dual cortex ARM Cortex-R5 subsystem
+ - 2 x C66x Digital signal processor sub system
+ - C71x Digital signal processor sub-system with MMA.
+
+More info can be found in TRM: http://www.ti.com/lit/pdf/spruil1
+
+Boot Flow:
+----------
+Boot flow is similar to that of AM65x SoC and extending it with remoteproc
+support. Below is the pictorial representation of boot flow:
+
++------------------------------------------------------------------------+-----------------------+
+| DMSC | MCU R5 | A72 | MAIN R5/C66x/C7x |
++------------------------------------------------------------------------+-----------------------+
+| +--------+ | | | |
+| | 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 | | | |
+| | | | +-------------+ | | |
+| | | | | Load | | | |
+| | | | | tispl.bin | | | |
+| | | | +-------------+ | | |
+| | | | | Load R5 | | | |
+| | | | | firmware | | | |
+| | | | +-------------+ | | |
+| | |<--------|---| Start A72 | | | |
+| | | | | and jump to | | | |
+| | | | | next image | | | |
+| | | | +-------------+ | | |
+| | | | | +-----------+ | |
+| | |---------|-----------------------|---->| Reset rls | | |
+| | | | | +-----------+ | |
+| | DMSC | | | : | |
+| |Services | | | +-----------+ | |
+| | |<--------|-----------------------|---->|*ATF/OPTEE*| | |
+| | | | | +-----------+ | |
+| | | | | : | |
+| | | | | +-----------+ | |
+| | |<--------|-----------------------|---->| *A72 SPL* | | |
+| | | | | +-----------+ | |
+| | | | | | Load | | |
+| | | | | | u-boot.img| | |
+| | | | | +-----------+ | |
+| | | | | : | |
+| | | | | +-----------+ | |
+| | |<--------|-----------------------|---->| *U-Boot* | | |
+| | | | | +-----------+ | |
+| | | | | | prompt | | |
+| | | | | +-----------+ | |
+| | | | | | Load R5 | | |
+| | | | | | Firmware | | |
+| | | | | +-----------+ | |
+| | |<--------|-----------------------|-----| Start R5 | | +-----------+ |
+| | |---------|-----------------------|-----+-----------+-----|----->| R5 starts | |
+| | | | | | Load C6 | | +-----------+ |
+| | | | | | Firmware | | |
+| | | | | +-----------+ | |
+| | |<--------|-----------------------|-----| Start C6 | | +-----------+ |
+| | |---------|-----------------------|-----+-----------+-----|----->| C6 starts | |
+| | | | | | Load C7 | | +-----------+ |
+| | | | | | Firmware | | |
+| | | | | +-----------+ | |
+| | |<--------|-----------------------|-----| Start C7 | | +-----------+ |
+| | |---------|-----------------------|-----+-----------+-----|----->| C7 starts | |
+| +---------+ | | | +-----------+ |
+| | | | |
++------------------------------------------------------------------------+-----------------------+
+
+- Here DMSC acts as master and provides all the critical services. R5/A72
+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: https://gitlab.denx.de/u-boot/u-boot
+ 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-j721e CFG_ARM64_core=y
+
+4. U-Boot:
+
+4.1. R5:
+$ make ARCH=arm CROSS_COMPILE=arm-linux-gnueabihf- j721e_evm_r5_defconfig O=/tmp/r5
+$ make ARCH=arm CROSS_COMPILE=arm-linux-gnueabihf- O=/tmp/r5
+
+4.2. A72:
+$ make ARCH=arm CROSS_COMPILE=aarch64-linux-gnu- j721e_evm_a72_defconfig O=/tmp/a72
+$ 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/a72
+
+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 |
+ | +-------------------+ |
+ | | | |
+ | | A72 ATF | |
+ | +-------------------+ |
+ | | | |
+ | | A72 OPTEE | |
+ | +-------------------+ |
+ | | | |
+ | | A72 SPL | |
+ | +-------------------+ |
+ | | | |
+ | | SPL DTB 1...N | |
+ | +-------------------+ |
+ +-----------------------+
+
+- sysfw.itb
+ +-----------------------+
+ | |
+ | FIT HEADER |
+ | +-------------------+ |
+ | | | |
+ | | sysfw.bin | |
+ | +-------------------+ |
+ | | | |
+ | | board config | |
+ | +-------------------+ |
+ | | | |
+ | | PM config | |
+ | +-------------------+ |
+ | | | |
+ | | RM config | |
+ | +-------------------+ |
+ | | | |
+ | | Secure config | |
+ | +-------------------+ |
+ +-----------------------+