| ================================================================================ |
| Useful notes on bulding and using of U-Boot on ARC HS Development Kit (AKA HSDK) |
| ================================================================================ |
| |
| BOARD OVERVIEW |
| |
| The DesignWare ARC HS Development Kit is a ready-to-use platform for rapid |
| software development on the ARC HS3x family of processors. |
| |
| For more information please visit: |
| https://www.synopsys.com/dw/ipdir.php?ds=arc-hs-development-kit |
| |
| User guide is availalble here: |
| https://github.com/foss-for-synopsys-dwc-arc-processors/ARC-Development-Systems-Forum/wiki/docs/ARC_HSDK_User_Guide.pdf |
| |
| It has the following features useful for U-Boot: |
| * On-board 2-channel FTDI TTL-to-USB converter |
| - The first channel is used for serial debug port (which makes it possible |
| to use a serial connection on pretty much any host machine be it |
| Windows, Linux or Mac). |
| On Linux machine typucally FTDI serial port would be /dev/ttyUSB0. |
| There's no HW flow-control and baud-rate is 115200. |
| |
| - The second channel is used for built-in Digilent USB JTAG probe. |
| That means no extra hardware is required to access ARC core from a |
| debugger on development host. Both proprietary MetaWare debugger and |
| open source OpenOCD + GDB client are supported. |
| |
| - Also with help of this FTDI chip it is possible to reset entire |
| board with help of a special `rff-ftdi-reset` utility, see: |
| https://github.com/foss-for-synopsys-dwc-arc-processors/rff-ftdi-reset |
| |
| * Micro SD-card slot |
| - U-Boot expects to see the very first partition on the card formatted as |
| FAT file-system and uses it for keeping its environment in `uboot.env` |
| file. Note uboot.env is not just a text file but it is auto-generated |
| file created by U-Boot on invocation of `saveenv` command. |
| It contains a checksum which makes this saved environment invalid in |
| case of maual modification. |
| |
| - There might be more useful files on that first FAT partition like |
| Linux kernl image in form of uImage (with or without built-in |
| initramfs), device tree blob (.dtb) etc. |
| |
| - Except FAT partition there might be others following the first FAT one |
| like Ext file-system with rootfs etc. |
| |
| * 1 Gb Ethernet socket |
| - U-Boot might get payload from TFTP server. This might be uImage, rootfs |
| image and anything else. |
| |
| * 2 MiB of SPI-flash |
| - SPI-flahs is used as a storage for image of an application auto-executed |
| by bootROM on power-on. Typically U-Boot gets programmed there but |
| there might be other uses. But note bootROM expects to find a special |
| header preceeding application image itself so before flashing anything |
| make sure required image is prepended. In case of U-Boot this is done |
| by invocation of `headerize-hsdk.py` with `make bsp-generate` command. |
| |
| |
| BUILDING U-BOOT |
| |
| 1. Configure U-Boot: |
| ------------------------->8---------------------- |
| make hsdk_defconfig |
| ------------------------->8---------------------- |
| |
| 2. To build Elf file (for example to be used with host debugger via JTAG |
| connection to the target board): |
| ------------------------->8---------------------- |
| make mdbtrick |
| ------------------------->8---------------------- |
| |
| This will produce `u-boot` Elf file. |
| |
| 3. To build artifacts required for U-Boot update in n-board SPI-flash: |
| ------------------------->8---------------------- |
| make bsp-generate |
| ------------------------->8---------------------- |
| |
| This will produce `u-boot.head` and `u-boot-update.scr` which should |
| be put on the first FAT partition of micro SD-card to be inserted in the |
| HSDK board. |
| |
| Note that Python3 script is used for generation of a header, thus |
| to get that done it's required to have Python3 with "pyelftools" installed. |
| |
| "pyelftools" could be installed with help of "pip" even w/o root rights: |
| ------------------------->8---------------------- |
| python3 -m pip install --user pyelftools |
| ------------------------->8---------------------- |
| |
| EXECUTING U-BOOT |
| |
| 1. The HSDK board is supposed to auto-start U-Boot image stored in on-board |
| SPI-flash on power-on. For that make sure DIP-switches in the corner of |
| the board are in their default positions: BIM in 1:off, 2:on state |
| while both BMC and BCS should be in 1:on, 2:on state. |
| |
| 2. Though it is possible to load U-Boot as a simple Elf file via JTAG right |
| in DDR and start it from the debugger. |
| |
| 2.1. In case of proprietary MetaWare debugger run: |
| ------------------------->8---------------------- |
| mdb -digilent -run -cl u-boot |
| ------------------------->8---------------------- |
| |
| |
| UPDATION U-BOOT IMAGE IN ON-BOARD SPI-FLASH |
| |
| 1. Create `u-boot.head` and `u-boot-update.scr` as discribed above with |
| `make bsp-generate` command. |
| |
| 2. Copy `u-boot.head` and `u-boot-update.scr` to the first FAT partition |
| of micro SD-card. |
| |
| 3. Connect USB cable from the HSDK board to the developemnt host and |
| fire-up serial terminal. |
| |
| 3. Insert prepared micro SD-card in the HSDK board, press reset button |
| and stop auto-execution of existing `bootcmd` pressing any key in serial |
| terminal and enter the following command: |
| ------------------------->8---------------------- |
| mmc rescan && fatload mmc 0:1 ${loadaddr} u-boot-update.scr && source ${loadaddr} |
| ------------------------->8---------------------- |
| Wait before you see "u-boot update: OK" message. |
| |
| 4. Press RESET button and enjoy updated U-Boot version. |
