Flashing the SPI NOR Flash

Before proceeding further, it’s recommended to familiarize yourself with the foundational concepts detailed in the Booting Essentials chapter. It will provides instructions on how to initiate the device from any accessible boot source, enabling you to proceed with the flashing procedure. Afterwards we’ll explore different approaches to flashing NOR flash: from an SD card or over a network connection.

The phyCORE-AM64x modules are optionally equipped with SPI NOR Flash. The SPI NOR flash partition table is defined in the U-Boot-only device tree k3-am642-phyboard-electra-rdk-u-boot.dtsi. It can be printed with:

uboot:~# mtd list
SF: Detected mt35xu512aba with page size 256 Bytes, erase size 4 KiB, total 64 MiB
List of MTD devices:
* nor0
  - device: flash@0
  - parent: spi@fc40000
  - driver: jedec_spi_nor
  - path: /bus@f0000/bus@fc00000/spi@fc40000/flash@0
  - type: NOR flash
  - block size: 0x1000 bytes
  - min I/O: 0x1 bytes
  - 0x000000000000-0x000004000000 : "nor0"
        - 0x000000000000-0x000000080000 : "ospi.tiboot3"
        - 0x000000080000-0x000000280000 : "ospi.tispl"
        - 0x000000280000-0x000000680000 : "ospi.u-boot"
        - 0x000000680000-0x0000006c0000 : "ospi.env"
        - 0x0000006c0000-0x000000700000 : "ospi.env.backup"

In this chapter, we will explore proceduress of flashing the OSPI NOR flash, starting from the point after the u-boot bootloader has successfully booted.

Flash SPI NOR Flash from SD Card

Flash SPI NOR from SD Card in U-Boot

The easiest way to access the SOM’s OSPI is to boot the SOM into U-Boot from an SD card (you may already be doing this). This guide will require a “Bootable SD card”, an SD card that has been flashed with the development kit’s BSP image. For instructions on how to create a bootable SD card, see this guide SD Card.

Power on the development kit and hit any key to stop in U-Boot.

Note

Be sure that you are booting the kit from SD card!

Within U-Boot, flash both SPLs and the U-Boot image into the OSPI storage device.

uboot:~# mtd list

uboot:~# mtd erase ospi.tiboot3
uboot:~# load mmc 1 ${loadaddr} tiboot3.bin
uboot:~# mtd write ospi.tiboot3 ${loadaddr} 0 ${filesize}

uboot:~# mtd erase ospi.tispl
uboot:~# load mmc 1 ${loadaddr} tispl.bin
uboot:~# mtd write ospi.tispl ${loadaddr} 0 ${filesize}

uboot:~# mtd erase ospi.u-boot
uboot:~# load mmc 1 ${loadaddr} u-boot.img
uboot:~# mtd write ospi.u-boot ${loadaddr} 0 ${filesize}

You can also include an initramfs and kernel on the OSPI NOR, which will allow you to boot into Linux using OSPI. Again, you will need to be booted into U-Boot with an SD card, and this guide also expects that you have a USB drive with an initramfs image on it. The name of the initramfs image will vary depending on what machine you are using.

uboot:~# load mmc 1 ${loadaddr} k3-am642-phyboard-electra-rdk.dtb
uboot:~# sf update ${loadaddr} ${spi_fdt_addr} ${filesize}
uboot:~# setenv size_fdt $filesize

uboot:~# load mmc 1 ${loadaddr} Image
uboot:~# sf update ${loadaddr} ${spi_image_addr} ${filesize}
uboot:~# setenv size_kern $filesize

uboot:~# usb start

uboot:~# load usb 0 ${loadaddr} phytec-initramfs-phyboard-electra-am64xx-2.cpio.xz
uboot:~# sf update ${loadaddr} ${spi_ramdisk_addr} ${filesize}
uboot:~# setenv size_fs $filesize

uboot:~# saveenv

uboot:~# mtd erase ospi.env
uboot:~# mtd erase ospi.env.backup
uboot:~# env export -c ${loadaddr}
uboot:~# mtd write ospi.env ${loadaddr} 0 ${filesize}
uboot:~# mtd write ospi.env.backup ${loadaddr} 0 ${filesize}

Flash SPI NOR from SD Card in Linux

If you have booted using the phytec-container-image-phyboard-electra-am64xx-2.wic image, you can find all required bootloader binaries in the automatically mounted /boot/ directory.
```
phyboard-electra-am64xx-2:~# ls /boot
tiboot3.bin*
tispl.bin*
u-boot.img*
...
```

Find the number of blocks to erase of the U-boot partition:

phyboard-electra-am64xx-2:~# mtdinfo /dev/mtd0
mtd0
Name:                           fc40000.spi.0
Type:                           nor
Eraseblock size:                131072 bytes, 128.0 KiB
Amount of eraseblocks:          512 (67108864 bytes, 64.0 MiB)
Minimum input/output unit size: 1 byte
Sub-page size:                  1 byte
Character device major/minor:   90:0
Bad blocks are allowed:         false

Erase the U-Boot partition and flash it:

phyboard-electra-am64xx-2:~# flash_erase /dev/mtd0 0 512
phyboard-electra-am64xx-2:~# flashcp /boot/tiboot3.bin /dev/mtd0
phyboard-electra-am64xx-2:~# flashcp /boot/tispl.bin /dev/mtd1
phyboard-electra-am64xx-2:~# flashcp /boot/u-boot.img /dev/mtd2

Flash SPI NOR Flash from Network

Flash SPI NOR from Network in U-Boot

Similar to updating the eMMC over a network, be sure to set up the development host correctly. The IP needs to be set to 192.168.3.10, the netmask to 255.255.255.0, and a TFTP server needs to be available. Before reading and writing to the MTD partitions is possible, the MTD list needs to be initilized:

uboot:~# mtd list
SF: Detected mt35xu512aba with page size 256 Bytes, erase size 4 KiB, total 64 MiB
List of MTD devices:
* nor0
  - device: flash@0
  - parent: spi@fc40000
  - driver: jedec_spi_nor
  - path: /bus@f0000/bus@fc00000/spi@fc40000/flash@0
  - type: NOR flash
  - block size: 0x1000 bytes
  - min I/O: 0x1 bytes
  - 0x000000000000-0x000004000000 : "nor0"
        - 0x000000000000-0x000000080000 : "ospi.tiboot3"
        - 0x000000080000-0x000000280000 : "ospi.tispl"
        - 0x000000280000-0x000000680000 : "ospi.u-boot"
        - 0x000000680000-0x0000006c0000 : "ospi.env"
        - 0x0000006c0000-0x000000700000 : "ospi.env.backup"

Flash both SPLs and the U-Boot image into the OSPI storage device.

phyboard-electra-am64xx-2:~# tftp ${loadaddr} tiboot3.bin
phyboard-electra-am64xx-2:~# mtd write ospi.tiboot3 ${loadaddr} 0 ${filesize}

phyboard-electra-am64xx-2:~# tftp ${loadaddr} tispl.bin
phyboard-electra-am64xx-2:~# mtd write ospi.tispl ${loadaddr} 0 ${filesize}

phyboard-electra-am64xx-2:~# tftp ${loadaddr} u-boot.img
phyboard-electra-am64xx-2:~# mtd write ospi.u-boot ${loadaddr} 0 ${filesize}

Flash SPI NOR from Network in Linux

Make sure all three bootloader binaries are available on the target, e.g. by copying them via scp:
```
host:~$ scp tiboot3.bin tispl.bin u-boot.img [email protected]:/root
```

Find the number of blocks to erase of the U-boot partition:

phyboard-electra-am64xx-2:~# mtdinfo /dev/mtd0
mtd0
Name:                           fc40000.spi.0
Type:                           nor
Eraseblock size:                131072 bytes, 128.0 KiB
Amount of eraseblocks:          512 (67108864 bytes, 64.0 MiB)
Minimum input/output unit size: 1 byte
Sub-page size:                  1 byte
Character device major/minor:   90:0
Bad blocks are allowed:         false

Erase the U-Boot partition and flash it:

phyboard-electra-am64xx-2:~# flash_erase /dev/mtd0 0 512
phyboard-electra-am64xx-2:~# flashcp tiboot3.bin /dev/mtd0
phyboard-electra-am64xx-2:~# flashcp tispl.bin /dev/mtd1
phyboard-electra-am64xx-2:~# flashcp u-boot.img /dev/mtd2