stm32h723zg Clause 45 MDIO

[heisenbug]

Hi all,

i see H7 supports clause 45 MDIO access, but in the HAL library looks not implemented, i see only clause 22.

How should i proceed to read/write c45 ?

 Thanks,

angelo

[mƎALLEm]

Hello,

Which MDIO interface you are talking about? is it the MDIO of the ETH or the MDIO slave (MDIOS)?

[heisenbug]

MDIO inside the ETH IP

[heisenbug]

Well, found now that the PHY chip i am using is supporting C22 to C45 bridge (multiple devices addressing), so don't need to add Clause 45 to HAL. Anyway, since h7 supports Clause 45, would be nice to have it imnplemented in HAL.  

[mƎALLEm]

Hello,

Internal ticket already raised for follow-up 177202

[mƎALLEm]

Hello,

I've got a feedback regarding that request. The decision was not to add Clause45 support for the actual product including H7 for many reason including the fact that there is no ST STM32 development kits is equipped with a Clause45-capable PHY. But Clause45 (maybe) it will be addressed in the HAL of newer products.

[leo2025]

STM32H7 clause 45 is supported by the chip, but not by the HAL library; Or does the chip itself not support it?

[Pavel A.]

@leo2025 Is your request related to the *slave* MDIO (MDIOS) of STM32F7, H7? The ETH of STM32 MCUs is not GBe anyway. If your advanced PHY has other host interfaces besides MDIO (I2C, SPI) consider using these.

[leo2025]

yeah, I need the mdio interface of the STM32H7xx Mac to read DSP 32-bit register data, and I don't need to use RMII or MII

[Pavel A.]

>  read DSP 32-bit register data

Hmm then maybe bit-bang the C45 MDIO protocol ?

[heisenbug]

Hi,

at least for stm32h7xx, both Clause 22 and 45 are supported in hardware.

What does it mean: that if you set c45e bit as 0 (default) the MDIO controller sends out data as per Clause 22. If c45e is set to 1, it sends C45.

I already added the functionality into HAL one year ago. 

https://github.com/STMicroelectronics/stm32h7xx-hal-driver/pull/51/commits/00928b443eaedabae4a47aa2210b3ce5c84b4adb

After long time waiting, probably one year or so, as you can see in the PR, ST replied i didn't signed a specific CLA agreement and the PR is refused. I decided to refuse also to spend time on this. Anyway, my commit works and you can use it from my PR.

regards,
Angelo Dureghello

 

[leo2025]

Thank you for your contribution！！

[heisenbug]

Just to be correct, i've read an older PR. Reason for refusing this is that ST cannot test this since there are no ST dev kits with clause45 phy. I tested this from Zephyr just soldering 2 mdio wires to an Analog Devices dev board (adin1100), and opening the 2 lines in the nucleo.