iMX6: PCI Express - multiple endpoint devices?

[pj0585]

Hi,

iMX6 PCI Express is a single lane PCI express (apart from iMX6 solo lite which does not have PCI express).

Can I have more that one PCI express endpoint device attached to a single lane?

Would I need to use a PCI Switch ?

Any inputs?

-Pj

[weidong_sun · Accepted solution]

Hello,Prasant,

     If you have only PCIe device , you can connect it to PCIe inteface on i.mx6 directly. If your PCIe devices are 2 or more, you will have to use a PCIe swtich ( root side : 1 LANE and end side has  2 or 3,or 4 ports with 1 LAN), at this time, PCIe on i.mx6 is act as root point.

Regards,

Weidong

[Yuri]

Are not there some misunderstanding regarding PCIe endpoint and PCIe port ?
Logically several endpoints may share the single port - is this correct ? 

[pj0585]

Yuri, my question was more on the hardware design aspect.

Yes, logically (bus structure in software) more than one endpoint could be attached to one PCIe Port. To achieve the same on the hardware end, when you have only one lane, you need to use a PCIe Switch.

If you want to contradict or you think my understanding is wrong, please reply, you may save me from a wrong hardware design!

-Pj

[pj0585]

Thanks a lot Weidong!

I also understood the same after googling, but wanted a confirmation of the same.

Are you aware of any freescale's development board / evaluation kit which makes use of a PCIe switch, that could serve as a reference design for me ?

Regards, Pj

[PradapRaj]

Hi Prasant,

iWave's Latest i.MX6 Developement kit - Raibow-G15D supports 4-Port PCIe switch on board. You can use this for your PCIe switch evaluation. Also this Dev Kit supports USB3.0 through PCIe. For details you can see the below link.

i.MX6 Q7 Development Kit | iWave Systems

Regards,

Pradap