DRA821U: Clarification on Internal 5port Ethernet Switch CPSW0

Hi Anish,

anish khanna yellapu said:

Do we have any separate documentation for CPSW, apart from reference manual and data sheet ? 

You can review the existing literature

1. Developing Ethernet based applications with RTOS and Linux

2. Why Ethernet firmware is required - E2E

3. Linux Virtual MAC driver

4. EthFW Introduction

anish khanna yellapu said:

Using ethernet switch internally will not increase pin count ?

Well, yes. If you use RGMII then for each port the Rx, Tx pins get added. If pin count is a concern then you can look at SGMII.

anish khanna yellapu said:

What is the advantages of having switch on  Soc, compared to switch on PCB ?

BOM cost reduction, Power savings, tighter SW integration. The built in switch has a lot of features like TSN etc which might cost a lot if you buy separately. Anyways I am guessing that even if you use an external switch you will have to interface it with the SoC through an ethernet port.

anish khanna yellapu said:

How to load firmware on CPSW0 ethernet switch.

Linux on A72 will do it for you via remoteproc, the RTOS bootloader also supports loading of it.

anish khanna yellapu said:

Correct my understanding CPSW0 is for main domain A72.

                                          MCU_CPSW is for R5F

Yes, that's usually the partitioning. You can use MCU_CPSW from A72 as well, it's natively supported.

anish khanna yellapu said:

If i don't want to use this 5port ethernet switch on the SOC and use the switch on PCB.

You will have to interface this external switch with SoC somehow, and the easiest way to do it is using the internal switch using MAC 2 MAC connection. Typically customers use at least one port of internal switch and connect to a PCB switch so as to save pins.

anish khanna yellapu said:

How to configure 5port switch as normal GMAC controller so that it can connect to external ethernet switches.

That is natively supported. Are you asking for separate ethernet interfaces for each physical port ? THat support will get added in SDK 8.1 (Dec 21) but it's already supported in HW.

Have you tested using an EVM ? That will be the fastest way to understand.

Regards

Vineet