From: Igor Opaniuk igor.opaniuk@toradex.com
Add initial readme.rst file which provides all needed information for obtaining a workable image ready for flashing for both eMMC/NAND versions of Colibri iMX7.
Signed-off-by: Igor Opaniuk igor.opaniuk@toradex.com Reviewed-by: Oleksandr Suvorov oleksandr.suvorov@toradex.com ---
v2: - Converted to reStructuredText format [Bin Meng]
board/toradex/colibri_imx7/readme.rst | 128 ++++++++++++++++++++++++++ 1 file changed, 128 insertions(+) create mode 100644 board/toradex/colibri_imx7/readme.rst
diff --git a/board/toradex/colibri_imx7/readme.rst b/board/toradex/colibri_imx7/readme.rst new file mode 100644 index 0000000000..e914f23c53 --- /dev/null +++ b/board/toradex/colibri_imx7/readme.rst @@ -0,0 +1,128 @@ +.. SPDX-License-Identifier: GPL-2.0+ + +U-Boot for Colibri iMX7 +======================= + +Quick Start +----------- + +- Build U-Boot +- NAND IMX image adjustments before flashing +- Flashing manually U-Boot to eMMC +- Flashing manually U-Boot to NAND +- Using ``update_uboot`` script + +Build U-Boot +------------ + +.. code-block:: bash + + $ export CROSS_COMPILE=arm-linux-gnueabi- + $ export ARCH=arm + $ make colibri_imx7_emmc_defconfig # For NAND: colibri_imx7_defconfig + $ make + +After build succeeds, you will obtain final ``u-boot-dtb.imx`` IMX specific +image, ready for flashing (but check next section for additional +adjustments for NAND). + +Final IMX program image includes (section ``6.6.7`` from `IMX7DRM +https://www.nxp.com/webapp/Download?colCode=IMX7DRM`_): + +* **Image vector table** (IVT) for BootROM +* **Boot data** -indicates the program image location, program image size + in bytes, and the plugin flag. +* **Device configuration data** +* **User image**: U-Boot image (``u-boot-dtb.bin``) + + +NAND IMX image adjustments prior to flashing +-------------------------------------------- + +1. U-Boot for both Colibri iMX7 NAND and eMMC versions +is built with HABv4 support (`AN4581.pdf +https://www.nxp.com/docs/en/application-note/AN4581.pdf`_) +enabled by default, which requires to generate a proper +Command Sequence File (CSF) by srktool from NXP (not included in the +U-Boot tree, check additional details in introduction_habv4.txt) +and concatenate it to the final ``u-boot-dtb.imx``. + +2. In case if you don't want to generate a proper ``CSF`` (for any reason), +you still need to pad the IMX image so i has the same size as specified in +in **Boot Data** section of IMX image. +To obtain this value, run: + +.. code-block:: bash + + $ od -X -N 0x30 u-boot-dtb.imx + 0000000 402000d1 87800000 00000000 877ff42c + 0000020 877ff420 877ff400 878a5000 00000000 + ^^^^^^^^ + 0000040 877ff000 000a8060 00000000 40b401d2 + ^^^^^^^^ ^^^^^^^^ + +Where: + +* ``877ff400`` - IVT self address +* ``877ff000`` - Program image address +* ``000a8060`` - Program image size + +To calculate the padding: + +* IVT offset = ``0x877ff400`` - ``0x877ff000`` = ``0x400`` +* Program image size = ``0xa8060`` - ``0x400`` = ``0xa7c60`` + +and then pad the image: + +.. code-block:: bash + + $ objcopy -I binary -O binary --pad-to 0xa7c60 --gap-fill=0x00 \ + u-boot-dtb.imx u-boot-dtb.imx.zero-padded + +3. Also, according to requirement from ``6.6.7.1``, the final image +should have ``0x400`` offset for initial IVT table. + +For eMMC setup we handle this by flashing it to ``0x400``, howewer +for NAND setup we adjust the image prior to flashing, adding padding in the +beginning of the image. + +.. code-block:: bash + + $ dd if=u-boot-dtb.imx.zero-padded of=u-boot-dtb.imx.ready bs=1024 seek=1 + +Flash U-Boot IMX image to eMMC +------------------------------ + +Flash the ``u-boot-dtb.imx`` binary to the primary eMMC hardware +boot area partition: + +.. code-block:: bash + + + => load mmc 1:1 $loadaddr u-boot-dtb.imx + => setexpr blkcnt ${filesize} + 0x1ff && setexpr blkcnt ${blkcnt} / 0x200 + => mmc dev 0 1 + => mmc write ${loadaddr} 0x2 ${blkcnt} + +Flash U-boot IMX image to NAND +------------------------------ + +.. code-block:: bash + + => load mmc 1:1 $loadaddr u-boot-dtb.imx.ready + => nand erase.part u-boot1 + => nand write ${loadaddr} u-boot1 ${filesize} + => nand erase.part u-boot2 + => nand write ${loadaddr} u-boot2 ${filesize} + +Using update_uboot script +------------------------- + +You can also usb U-boot env update_uboot script, +which wraps all eMMC/NAND specific command invocation: + +.. code-block:: bash + + => load mmc 1:1 $loadaddr u-boot-dtb.imx + => run update_uboot +