topic Re: PCMCIA on iMX31 ADS in i.MX Processors

PCMCIA on iMX31 ADS

Herg — Tue, 31 Oct 2006 05:26:41 GMT

I'm trying to get the PCMCIA port on the iMX31 ADS dev board working under Linux, and I'm running into some difficulty. I've tried multiple cards including CF memory cards and a headmounted video display with a CF interface.

When a card is inserted, it is detected:

pccard: PCMCIA card inserted into slot 0

It appears that the CIS cannot be read:

mx31# dump_cis
Socket 0:
no CIS present
mx31# cardctl ident
Socket 0:
no product info available
mx31# cardctl info
PRODID_1=""
PRODID_2=""
PRODID_3=""
PRODID_4=""
MANFID=0000,0000
FUNCID=255

At the moment, I'm not even sure if it is a hardware configuration or software issue.

Re: PCMCIA on iMX31 ADS

mke_et — Tue, 31 Oct 2006 20:26:47 GMT

Well, I have NO idea about your platform. Or Linux. Or C....

I have no idea what is 'automatic' in your platform or with your driver, if any.

But, after you get the insertion event, did the power turn on? Did the system configure for 'attribute space' to read the CIS? Who walks the tuples? Is the driver doing that?

Get a PCMCIA extender card with LEDs for power and a 'breakout bus' so you can see what is going on.

Re: PCMCIA on iMX31 ADS

Herg — Tue, 31 Oct 2006 21:31:32 GMT

Yes, there is 3.3V on the power pins. I see activity on the data/address bus when I run the script '/etc/rc.d/init.d/pcmcia start', but nothing when doing 'dump_cis' or 'cardctl'.

Looking at the schematic, I see that there are transceivers on the PCMCIA bus, and the output enable (active low) remains high when trying to read the CIS. I'm in the process of trying to understand how this is supposed to work.

Re: PCMCIA on iMX31 ADS

mke_et — Thu, 02 Nov 2006 00:10:22 GMT

Wait, are CF cards supposed to have tuples? Or are they dedicated 'ATA'? How are you getting the CF card into a PCMCIA slot?

Wow, you can tell I've been out of it for a long time!

Re: PCMCIA on iMX31 ADS

Herg — Thu, 02 Nov 2006 00:35:45 GMT

Yes, CF cards do have tuples. The adapter is completely passive, and simply re-routes the 50 CF signals to the 68 PCMCIA signals. I originally used the adapter with the headmounted display attached to a XScale PXA270, and I'm trying to port the driver I wrote to the iMX31.

I've tracked the /OE problem back to the PC_POE signal on the iMX31. There is no activity except while it is loading the driver. I've turned on the debugging messages, and I'm trying to wade my way through this.

Thanks for the help. I have a feeling I'm going to have to get in contact with whoever wrote the low level driver (mx31ads_pcmcia).