OSD32MP1-BRK

[ML]

Hi all

I would like to program the 4K EEPROM residing in OSD32MP157C chip.

I am using OSD32MP1-BRK which contains the chip.

Anyone can advise me how to do it?

[Neeraj Dantu]

ML,

The EEPROM is configured in the device tree here: https://github.com/octavosystems/OSD32MP1-BRK-device-tree/blob/kirkstone/linux-v5.15.24-stm32mp1-r1/stm32mp157c-osd32mp1-brk.dts#L837. You should be able to access it using the SYSFS via ‘/sys/bus/i2c/devices/3-0050/’. ‘3’ is the I2C interface number that the EEPROM is on and ‘0050’ is the address of the EEPROM. This directory contains file “eeprom”, which you can use to interact with the EEPROM. Please see https://stackoverflow.com/a/60781512.

There are a number of other ways including using Linux IOCTL/python libraries/[shell commands: i2ctools]. See https://wiki.st.com/stm32mpu/wiki/I2C_i2c-tools for useful info on using i2ctools.

Best,
Neeraj

[ML]

HI Neeraj, thanks for the reply!

I am green horn in this area ;p so not quite sure what u meant by to access the EEPROM (in the device tree) via SYSFS.

What are the appropriate software platform I will need to install in order to do what u meant? Also how do I download the modification (done to the EEPROM) to my development board – OSD32MP1-BRK? Many thanks to u again!

[Neeraj Dantu]

ML,

Please see https://www.kernel.org/doc/Documentation/i2c/i2c-sysfs.rst for an overview of I2C SYSFS. The EEPROM driver invoked by the device tree provides entries in /sys/bus/i2c/devices directory that you can interact with as files.

The default Linux image should come with EEPROM device driver enabled. Images for BRK are available here: https://octavosystems.com/octavo_products/osd32mp1-brk/#Software/. See also: https://octavosystems.com/app_notes/osd32mp1-brk-getting-started/.

Best,
Neeraj

[ML]

I follow the steps listed here https://octavosystems.com/app_notes/osd32mp1-brk-getting-started/#trouble

But I am still unable to detect new network adapter called Remote NDIS Compatible Device though I have configured the boot switch to 101 and also saw the red LED blinking.

I cannot find this adapter in network connection or under Other devices in the Device Manager.

Can anyone advise me what can be done?

[Neeraj Dantu]

ML,

I would suggest trying a different USB cable(some cables only provide power).

Also, you should be able to use a USB to UART adapter to connect to the UART interface(marked TX, RX and GND) near the SD card slot. This will allow you to use a program like Putty to open a terminal on your computer and monitor the console log output of the BRK board when it is booting. After it boots, it will also provide a console for you to type in commands like “ifconfig” to see the Ethernet configuration from the board side. An example adapter can be found here: https://learn.sparkfun.com/tutorials/sparkfun-usb-to-serial-uart-boards-hookup-guide/all.

Best,
Neeraj

[ML]

Thanks Neeraj,

I did the following:

Write to EEPROM:

echo -n -e ‘\xAB\xCD\xEF’ | dd of=/sys/bus/i2c/devices/3-0050/eeprom bs=1 seek=16

Added delay

sleep 0.1  # Add a small delay to ensure write completion

Tried to read the EEPROM:

dd if=/sys/bus/i2c/devices/3-0050/eeprom bs=1 count=3 skip=16 2>/dev/null | hexdump -C

Result:

00000000  ff ff ff                                          |…|

00000003

I expected to see AB CD EF but did not. Can you advise me what went wrong?

• This reply was modified 2 weeks, 3 days ago by ML.

[Neeraj Dantu]

ML,

My apologies, I did not realize a fix was not issued to the images on the website. The issue is that the EEPROM follows 16 bit addressing format and by default 8 bit addressing is used by the at24 driver.

To fix this, the device tree for the board needs “address-width = <16>;” definition in eeprom node.

Here is a Debian image that has this fix: https://octavosystems.com/octavosystems.com/wp-content/uploads/2025/02/FlashLayout_sdcard_stm32mp157c-osd32mp1-brk-trusted.zip. I am working on updating the images on the web and OpenSTLinux layers.

Please let me know how the new image works for you.

Best,
Neeraj

[ML]

I downloaded the Debian image from the above link u provided using Etcher sw. But encountered the following Error: (0,h.requestMetaData) is not a function during programming of the image

Can advise what to be done?

Many tks

[Neeraj Dantu]

Hey ML,

I have re-verified that the image downloaded from the above post is OK. I also used Etcher(on Ubuntu OS) to program the SD card to make sure there is no problem with the image file. Can you try a different SD card/host machine/Etcher version?

Best,
Neeraj

[ML]

Thanks Neeraj, I am able to load in the debian image into a brand new SD card.

Write to EEPROM:

debian@localhost:~$ sudo echo -n -e ‘\xAB\xCD\xEF’ | sudo dd of=/sys/bus/i2c/devices/3-0050/eeprom bs=1 seek=16

Result:

3+0 records in

3+0 records out

3 bytes copied, 0.0414865 s, 0.1 kB/s

Read from EEPROM

debian@localhost:~$ sudo dd if=/sys/bus/i2c/devices/3-0050/eeprom bs=1 count=3 skip=16 2>/dev/null | hexdump -C

Result:

00000000  ff ff ff                                          |…|

00000003

Checking i2c status:

debian@localhost:~$ sudo i2cdetect -y 3

Result:

0  1  2  3  4  5  6  7  8  9  a  b  c  d  e  f

00:                         — — — — — — — —

10: — — — — — — — — — — — — — — — —

20: — — — — — — — — — — — — — — — —

30: — — — UU — — — — — — — — — — — —

40: — — — — — — — — — — — — — — — —

50: UU — — — — — — — — — — — — — — —

60: — — — — — — — — — — — — — — — —

70: — — — — — — — —

 

I am still unable to write to the EEPROM at address 0x50 & strangely the i2C at this address is unavailable (UU) for use?

• This reply was modified 1 week, 4 days ago by ML.

[ML]

Hi Neeraj

Can u help me try on your side the Debian image is it possible to write & readback from the EEPROM(in the SiP chip) on the OSD32Mp1-BRK development card? Many thanks!

[Neeraj Dantu]

ML,

This is how I wrote and read back from EEPROM on OSD32MP1-BRK:

root@localhost:/sys/bus/i2c/devices/3-0050# echo “OSD32MP1” > eeprom
root@localhost:/sys/bus/i2c/devices/3-0050# cat eeprom
OSD32MP1
?????????????????????????????????????????????????????????

You are seeing “UU” in i2cdetect output because the driver for the EEPROM is in control of the I2C device. You can still force i2c tools to interact with the EEPROM using “-f” flag if you need to.

Please make sure you also set the EEPROM_WP(write protect) switch position located in the BOOT switches(switch #4) to the position towards the Micro-USB port. This disables the write protect on the EEPROM so you can write to it.

Best,
Neeraj

[ML]

Hi Neeraj,

Thanks now it is working well :).

The SiP part on my development card (OSD32MP1-BRK) is OSD32MP157F but is it possible for me to replace the on-board SiP with another SiP – OSD32MP153C? Because I want to use OSD32MP153C but I only have this development card.

[Neeraj Dantu]

ML,

You should be able to use 7F device as 3C by disabling the extra hardware as 7F is a super-set device that has all the features of 3C. Additionally, this patch: https://github.com/octavosystems/osd32mp1-build-tools/blob/master/patches/linux-5.10/0025-Fix-device-tree-for-800MHz-speedgrade-MP1-to-work-wi.patch allows you to run the 7F device at 3C speed(650MHz).

Best,
Neeraj

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