MMC disconnects after connecting to DSTREAM debugger

[zixet]

Hi, I'm trying to extract linux kernel ETM data from Vybrid(VF65GS10) tower board through Mictor port and DSTREAM debugger unit. I'm using MMC as a rootfs device but after connecting the debugger, the sdcard gets disconnected and I loss the MMC and my rootfs. Does anyone have any idea what's going on here? Thanks, Amir

[naoumgitnik]

Dear Amir,

May you clarify your problem, please? - Do you mean the problem is due to that the same Vybrid IOs are shared by DSTREAM (on the Mictor port) and the SD card?

Regards, Naoum Gitnik.

[zixet]

Exactly! it seems that MMC and Mictor ports have some pins in common that cause this problem.

[naoumgitnik · Accepted solution]

Hello Amir,

Unfortunately, this is the design limitation - a small board with quite many peripherals connected to the processor with a limited number of IOs.

If you fully use the Mictor port, I am afraid you will have to make Vybrid boot from a different source - QuadSPI, NAND, or UART/USB. - See details for the Tower module's header J22 (Boot Options) on the schematic and/or in the User Manual.

Regards, Naoum Gitnik.

[zixet]

Yeah, I guess so.

My problem is not boot becuase MMC can load u-boot and kernel image and then pass everything to rootfs. That's why I was looking for making USB work in this topic to store my rootfs there. And again, unfortunately, I have faced another problem in compiling newer linux kernel for Vybrid.

Is TimeSys responsible for maintaning software like BSP for Vybrid? I have contacted them and still wating for their response.

BTW, thank you for you response.

[naoumgitnik]

Dear Timesys Support,

May you comment on the last customer's question regarding you and BSP (and perhaps advise something in general, too), please?

Thanks in advance, Naoum Gitnik.

[timesyssupport]

Hi Naoum and Amir,

Timesys is responsible for maintaining the Linux 3.0 kernel and BSP that we provide - however the mainline Linux support for Vybrid has not been added by us. Mainline support is limited feature-wise at this time. We are currently working on updating our BSP offering from Linux 3.0 to 3.13. We expect the initial release to be ready by end of July.

There is not a USB controller driver for Vybrid in mainline Linux. However, we have been able to mount an RFS via NFS with mainline Linux as an alternate boot mechanism - the kernel configuration we used is attached.

Thanks,

Timesys Support