--- /dev/null
+.. SPDX-License-Identifier: GPL-2.0+ OR BSD-3-Clause
+.. sectionauthor:: Udit Kumar <u-kumar1@ti.com>
+
+J7200 Platforms
+===============
+
+Introduction:
+-------------
+The J7200 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
+
+More info can be found in TRM: https://www.ti.com/lit/pdf/spruiu1
+
+Boot Flow:
+----------
+Below is the pictorial representation of boot flow:
+
+.. code-block:: text
+
+ +------------------------------------------------------------------------+-----------------------+
+ | DMSC | MCU R5 | A72 | MAIN R5/C7x |
+ +------------------------------------------------------------------------+-----------------------+
+ | +--------+ | | | |
+ | | Reset | | | | |
+ | +--------+ | | | |
+ | : | | | |
+ | +--------+ | +-----------+ | | |
+ | | *ROM* |----------|-->| Reset rls | | | |
+ | +--------+ | +-----------+ | | |
+ | | | | : | | |
+ | | ROM | | : | | |
+ | |services| | : | | |
+ | | | | +-------------+ | | |
+ | | | | | *R5 ROM* | | | |
+ | | | | +-------------+ | | |
+ | | |<---------|---|Load and auth| | | |
+ | | | | | tiboot3.bin | | | |
+ | | Start | | +-------------+ | | |
+ | | TIFS |<---------|---| Start | | | |
+ | | | | | TIFS | | | |
+ | +--------+ | +-------------+ | | |
+ | : | | | | | |
+ | +---------+ | | Load | | | |
+ | | *TIFS* | | | system | | | |
+ | +---------+ | | Config data | | | |
+ | | |<--------|---| | | | |
+ | | | | +-------------+ | | |
+ | | | | : | | |
+ | | | | : | | |
+ | | | | : | | |
+ | | | | +-------------+ | | |
+ | | | | | *R5 SPL* | | | |
+ | | | | +-------------+ | | |
+ | | | | | DDR | | | |
+ | | | | | config | | | |
+ | | | | +-------------+ | | |
+ | | | | | Load | | | |
+ | | | | | tispl.bin | | | |
+ | | | | +-------------+ | | |
+ | | | | | Load R5 | | | |
+ | | | | | firmware | | | |
+ | | | | +-------------+ | | |
+ | | |<--------|---| Start A72 | | | |
+ | | | | | and jump to | | | |
+ | | | | | DM fw image | | | |
+ | | | | +-------------+ | | |
+ | | | | | +-----------+ | |
+ | | |---------|-----------------------|---->| Reset rls | | |
+ | | | | | +-----------+ | |
+ | | TIFS | | | : | |
+ | |Services | | | +-----------+ | |
+ | | |<--------|-----------------------|---->|*ATF/OPTEE*| | |
+ | | | | | +-----------+ | |
+ | | | | | : | |
+ | | | | | +-----------+ | |
+ | | |<--------|-----------------------|---->| *A72 SPL* | | |
+ | | | | | +-----------+ | |
+ | | | | | | Load | | |
+ | | | | | | u-boot.img| | |
+ | | | | | +-----------+ | |
+ | | | | | : | |
+ | | | | | +-----------+ | |
+ | | |<--------|-----------------------|---->| *U-Boot* | | |
+ | | | | | +-----------+ | |
+ | | | | | | prompt | | |
+ | | | | | +-----------+ | |
+ | | | | | | Load R5 | | |
+ | | | | | | Firmware | | |
+ | | | | | +-----------+ | |
+ | | |<--------|-----------------------|-----| Start R5 | | +-----------+ |
+ | | |---------|-----------------------|-----+-----------+-----|----->| R5 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/k3-image-gen/k3-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. DM Firmware:
+ Tree: git://git.ti.com/processor-firmware/ti-linux-firmware.git
+ Branch: ti-linux-firmware
+
+5. U-Boot:
+ Tree: https://source.denx.de/u-boot/u-boot
+ Branch: master
+
+Build procedure:
+----------------
+1. SYSFW:
+
+.. code-block:: bash
+
+ make ARCH=arm CROSS_COMPILE=arm-none-linux-gnueabihf- SOC=j7200 SBL=u-boot-spl.bin SYSFW_PATH=<path to sysfw>/ti-fs-firmware-j7200-gp.bin
+ u-boot-spl.bin is generated at step 4.
+
+2. ATF:
+
+.. code-block:: bash
+
+ make CROSS_COMPILE=aarch64-linux-gnu- ARCH=aarch64 PLAT=k3 TARGET_BOARD=generic SPD=opteed
+
+3. OPTEE:
+
+.. code-block:: bash
+
+ make PLATFORM=k3-j7200 CFG_ARM64_core=y
+
+4. U-Boot:
+
+* 4.1 R5:
+
+.. code-block:: bash
+
+ make CROSS_COMPILE=arm-linux-gnueabihf- j7200_evm_r5_defconfig O=build/r5
+ make CROSS_COMPILE=arm-linux-gnueabihf- O=build/r5
+
+* 4.2 A72:
+
+.. code-block:: bash
+
+ make CROSS_COMPILE=aarch64-linux-gnu- j7200_evm_a72_defconfig O=build/a72
+ make CROSS_COMPILE=aarch64-linux-gnu- ATF=<ATF dir>/build/k3/generic/release/bl31.bin TEE=<OPTEE OS dir>/out/arm-plat-k3/core/tee-pager_v2.bin DM=<DM firmware>/ti-dm/j7200/ipc_echo_testb_mcu1_0_release_strip.xer5f O=build/a72
+
+Target Images
+--------------
+Copy the below images to an SD card and boot:
+ - tiboot3.bin from step 1
+ - tispl.bin, u-boot.img from 4.2
+
+Image formats:
+--------------
+
+- tiboot3.bin:
+
+.. code-block:: console
+
+ +-----------------------+
+ | X.509 |
+ | Certificate |
+ | +-------------------+ |
+ | | | |
+ | | R5 | |
+ | | u-boot-spl.bin | |
+ | | | |
+ | +-------------------+ |
+ | | | |
+ | | FIT header | |
+ | | +---------------+ | |
+ | | | | | |
+ | | | DTB 1...N | | |
+ | | +---------------+ | |
+ | +-------------------+ |
+ | | | |
+ | | FIT HEADER | |
+ | | +---------------+ | |
+ | | | | | |
+ | | | sysfw.bin | | |
+ | | +---------------+ | |
+ | | | | | |
+ | | | board config | | |
+ | | +---------------+ | |
+ | | | | | |
+ | | | PM config | | |
+ | | +---------------+ | |
+ | | | | | |
+ | | | RM config | | |
+ | | +---------------+ | |
+ | | | | | |
+ | | | Secure config | | |
+ | | +---------------+ | |
+ | +-------------------+ |
+ +-----------------------+
+
+- tispl.bin
+
+.. code-block:: console
+
+ +-----------------------+
+ | |
+ | FIT HEADER |
+ | +-------------------+ |
+ | | | |
+ | | A72 ATF | |
+ | +-------------------+ |
+ | | | |
+ | | A72 OPTEE | |
+ | +-------------------+ |
+ | | | |
+ | | R5 DM FW | |
+ | +-------------------+ |
+ | | | |
+ | | A72 SPL | |
+ | +-------------------+ |
+ | | | |
+ | | SPL DTB 1...N | |
+ | +-------------------+ |
+ +-----------------------+
+
+
+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.
+
+The following table shows some common boot modes used on J7200 platform. More
+details can be found in the Technical Reference Manual:
+https://www.ti.com/lit/pdf/spruiu1 under the `Boot Mode Pins` section.
+
+
+*Boot Modes*
+
+============ ============= =============
+Switch Label SW9: 12345678 SW8: 12345678
+============ ============= =============
+SD 00000000 10000010
+EMMC 01000000 10000000
+OSPI 01000000 00000110
+UART 01110000 00000000
+USB DFU 00100000 10000000
+============ ============= =============
+
+For SW8 and SW9, the switch state in the "ON" position = 1.
+
+eMMC:
+-----
+ROM supports booting from eMMC raw read or UDA FS mode.
+
+Below is memory layout in case of booting from
+boot 0/1 partition in raw mode.
+
+Current allocated size for tiboot3 size is 1MB, tispl is 2MB.
+
+Size of u-boot.img is taken 4MB for refernece,
+But this is subject to change depending upon atf, optee size
+
+.. code-block:: console
+
+ boot0/1 partition (8 MB) user partition
+ 0x0+----------------------------------+ 0x0+------------------------+
+ | tiboot3.bin (1 MB) | | |
+ 0x800+----------------------------------+ | |
+ | tispl.bin (2 MB) | | |
+ 0x1800+----------------------------------+ | |
+ | u-boot.img (4MB) | | |
+ 0x3800+----------------------------------+ | |
+ | | | |
+ 0x3900+ environment | | |
+ | | | |
+ 0x3A00+----------------------------------+ +-------------------------+
+
+In case of UDA FS mode booting, following is layout.
+
+All boot images tiboot3.bin, tispl and u-boot should be written to
+fat formatted UDA FS as file.
+
+.. code-block:: console
+
+ boot0/1 partition (8 MB) user partition
+ 0x0+---------------------------------+ 0x0+-------------------------+
+ | | | tiboot3.bin* |
+ 0x800+----------------------------------+ | |
+ | | | tispl.bin |
+ 0x1800+----------------------------------+ | |
+ | | | u-boot.img |
+ 0x3800+----------------------------------+ | |
+ | | | |
+ 0x3900+ | | environment |
+ | | | |
+ 0x3A00+----------------------------------+ +-------------------------+
+
+
+
+In case of booting from eMMC, write above images into raw or UDA FS.
+and set mmc partconf accordingly.