AM5718: PCIe enumeration

Mohsen Khayami

Part Number: AM5718

Champs

Like to understand if we connect the PCIe bus to a windows based PC and use it as an end point. The processor is not initialized until the kernel is booted and stuff. What would happen when the PC bios does the enumeration on the PCIe i assume it does not see the AM5718 device. When the AM5718 is powered up and running the kernel how does it tell the PCIe on the windows PC that you have a AM5718 device as a PCIe end point?

I hope this is clear.

Thanks

Regards

Mohsen

over 7 years ago

0 Biser Gatchev-XID over 7 years ago

TI__Guru**** 393215 points

Hi,

The PCIe experts have been notified. They will respond here.

0 Rex Chang over 7 years ago in reply to Biser Gatchev-XID

TI__Guru 50170 points

HI, Mohsen,

In out 2 EVM connection scenario, the End Point needs to come up and be configured as EP through sysfs before RC powers up. Otherwise, RC EVM does not see the EP. It may apply to PC as well.

Rex

0 -DK- over 7 years ago in reply to Rex Chang

TI__Mastermind 27720 points

To add to Rex's statement: Depending on the version of Window in use, and the configuration of the WinPC, it may be possible to force the OS to perform a PnP re-enumeration. For example, ExpressCard is a PCIe derivative that supports PnP outside the control of the system BIOS.

It may be as simple as clicking the "Scan for Hardware Changes" in WinOS Device Manager.

0 Mohsen Khayami over 7 years ago in reply to -DK-

TI__Mastermind 22391 points

Rex & DK

Thanks for the reply sounds like we might be able to do this we shall see.

Regards

Mohsen

0 Mohsen Khayami over 7 years ago in reply to Mohsen Khayami

TI__Mastermind 22391 points

One question can the PCIe be configured in Uboot as a end point?? So it might be able to do the enumaration before the kernel boots?? or the kernel is involved with the enumeration stuff??

Thanks

Regards
Mohsen

0 Rex Chang over 7 years ago in reply to Mohsen Khayami

TI__Guru 50170 points

Mohsen,

Here is more info on the EndPoint mode, processors.wiki.ti.com/.../Linux_Core_PCIe_EP_User's_Guide

Rex

Processors

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AM5718: PCIe enumeration