Hi,

I am using AT91SAM9G20-EK(2mmc) Based custom board, I have 2 SD Card Slots.

I have given the same Information to the Linux kernel 2.6.38.

I have attached the Schematics of SD Card also.

While inserting the SD Card the Message as follows,

mmc1: host does not support reading read-only switch. assuming write-enable.
mmc1: new SDHC card at address e624
mmcblk0:p1

After typing the command "mdev -s"

I could see the device file lin "/dev/mmcblk0" and "/dev/mmcblk0p1"


The Problem is not mounting the "/dev/mmcblk0p1"

Also fdisk command or any command related to /dev/mmcblkop1 not working!!!!!!!!

1> I have enabled atmel_mci driver for two SD Card Slot.
2> THUMB Support configured
3> My Linux kernel supports vfat file system
4> I have foarmatted the SD Card using windows FAT file system.

This problem not faced yet.

Any Possible solition?.


Thenral,

Pricol Tech. India.

Check very carefully all your pin assignments, and how the board configuration file is defining pins and functionality.

Does it work on a real AT91SAM9G20-EK board with the two MMC slots? What differences do you have compared to the EK board?

If you use the AT91SAM9G20EK_2MMC you have a problem.
You need to connect PC2 and PC9 to GND on the PIOC connector.
The card detect signal is bogus. Does not change state when
a card is inserted....

Didnt do any measurements on this, but my Linux 2.6.39 kernel
did not detect any cards, neither SDIO nor Memory.
When I connected the wire between Slot A and PC2, the card was suddenly detected.

Other problems you might run into, is that you need pullups on the DAT[3..0]
and the CMD line. Beware that the clock is shared between slot A and slot B.

The driver in linux 2.6.39 will enable slot B as default, but if it detects that
it is a SAM9260EK_2MMC; it will change its mind and use slot A.
Unlike the SAM9M10/G45 driver it will not enable both slots.

There is a bug in slot B, so you cannot use it for SDIO, and you can
only boot from Slot A, so you cannot boot from SD when you
are using an SDIO card.

[quote="ulf"]If you use the AT91SAM9G20EK_2MMC you have a problem.
You need to connect PC2 and PC9 to GND on the PIOC connector.
The card detect signal is bogus. Does not change state when
a card is inserted....

Didnt do any measurements on this, but my Linux 2.6.39 kernel
did not detect any cards, neither SDIO nor Memory.
When I connected the wire between Slot A and PC2, the card was suddenly detected.

Other problems you might run into, is that you need pullups on the DAT[3..0]
and the CMD line. Beware that the clock is shared between slot A and slot B.

The driver in linux 2.6.39 will enable slot B as default, but if it detects that
it is a SAM9260EK_2MMC; it will change its mind and use slot A.
Unlike the SAM9M10/G45 driver it will not enable both slots.

There is a bug in slot B, so you cannot use it for SDIO, and you can
only boot from Slot A, so you cannot boot from SD when you
are using an SDIO card.[/quote]



Hi ,

I have fixed the problem by changing the sam9g20.c file by adding detect pin as ENODEV . Now I could mount and work with both SD Card Slots simultaneously .

Thenral