Vikas,
[quote user="Vikas Rustagi"]So shouldn't we make this pin pulled LOW to fool processor, that eMMC is permanently connected insted of HIGH?[/quote]
In eMMC case, SD1_SDCD pin is not used (it is input pin), and DM814x datasheet is providing the following info:
4.4 Handling Unused Pins
When device signal pins are unused in the system, they can be left unconnected unless otherwise noted in the Terminal Functions tables (see Section 3.2). For unused input pins, the internal pull resistor should be enabled, or an external pull resistor should be used, to prevent floating inputs. Unless otherwise noted, all supply pins must always be connected to the correct voltage, even when their associated signal pins are unused.
And it seems that the DM814x MMC driver does not use SD1_SDCD pin for card detect:
http://e2e.ti.com/support/dsp/davinci_digital_media_processors/f/716/p/179512/717206.aspx#717206
The other thing to look for is the Write Protect and Card Detect lines. These are GPIOs. Usually WP and CD can be optional. If not specified, The MMC driver is supposed to assume always writeable and always inserted.
[quote user="Vikas Rustagi"]
We also tried this, that if we pulled this line externally LOW, or kept this SD_CD line floating, and did the internal pull down enabled by,
omap_writel(0x00040002, 0x4814093c); /*PINCNTL80 - MMC1_SDCD*/
we are able to detect the MMC0.
[/quote]
I suspect that if you try with pull up, you should also be able to detect the eMMC?
The card detect functionality is implemented in interrupt mode only. Initially, the card insert and remove status registers bits were used to cause interrupts. But due to a race condition encountered in our driver code, we switched to GPIO based interrupt implementation for TI814x.
You can find the relevant patches implementing the GPIO based card insert/remove functionality here:
1) Uboot patches http://arago-project.org/git/projects/?p=u-boot-omap3.git;a=commit;h=3c863dfc6777dc062d40ab51eb9a84a1bb3d64e1
ti8148: mmc: use gpio pin for card detection
2) Kernel patches (http://arago-project.org/git/projects/?p=linux-omap3.git;a=shortlog):
ti81xx: mmc: remove the usage of card detect status...
ti8148: mmc: use gpio pin for card detection
Best regards,
Pavel