AM3352: MDIO to read marvell 88e6341 switch

Rui Huang

Part Number: AM3352

Hi, we are using marvell 88e6341 switch in our custom board, am3352's RGMII1 is connected to switch P0.

After power startup, switch's PHY ports can be linked up, checking by connecting to PC's rj45 port, however, we can't read switch register by am3352's MDIO in the uboot.

In our custom board, there is another marvell phy chip 88e1510 connected to RGMII0, however, we can read its register. Does anyone know how to debug this issue? I assume switch chip is working already. Thanks.

over 3 years ago

0 Schuyler Patton over 3 years ago

TI__Mastermind 37860 points

Hi,

Unfortunately TI does not support external switches.

The MDIO support in u-boot is geared towards the MII registers. How are you trying to read the registers?

Best Regards,

Schuyler

0 Rui Huang over 3 years ago

Prodigy 10 points

Hi,

Thanks for your information. I've noticed from other thread that MAC-MAC connection to switch is not supported, can you confirm that? I have to redesign our board.

About MDIO, I am using mii info to list all device. and 88e6341's PHY address is set to 0x3 and 0xc, however they are not able to list. And also, mii read can't work too.

mii read 0x3 0, mii read 0xc 0

0 Schuyler Patton over 3 years ago in reply to Rui Huang

TI__Mastermind 37860 points

Hi,

While the switch is not supported by TI there have been users who have successfully used an external switch in their application.

I do not have experience here, does the switch respond to multiple mdio addresses? Does mii read work with the other PHY?

Best Regards,

Schuyler

0 Rui Huang over 3 years ago in reply to Schuyler Patton

Prodigy 10 points

Hi Schuyler,

Thanks for your information, I've found the link here: https://e2e.ti.com/support/processors/f/processors-forum/600196/linux-dra744-ethernet-smi-bus-timing-with-marvell-88e6390xa0.

It seems I have the same issue. Do you have any software workaround from AM3352 perspective, since we are using Marvell's switch.

Best regards,

Rui

0 Schuyler Patton over 3 years ago in reply to Rui Huang

TI__Mastermind 37860 points

Hi,

Unfortunately TI does not have an example how to implement MDIO over 2 GPIOs unfortunately. I noticed there are other posts concerning Marvell Switches on the e2e.ti.com forum. Some users may have posted a solution that you might want to review. You can use a site search like this:

site:e2e.ti.com Marvell

Best Regards,

Schuyler

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AM3352: MDIO to read marvell 88e6341 switch