[U-Boot] Missing mtd device

[Gary Thomas <gary@mlbassoc.com>]

On 2012-05-23 03:57, Michael Moller wrote:
> Hi u-booters
>
> I'm at my wit's end.  I really hope you can help.
>
> I have tried updating the u-boot on a Davinci DM365 based board using
> various versions of u-boot, including the latest from the git
> repository.
>
> After setting CROSS_COMPILE and configuring with
> "make davinci_dm365evm_config", everything builds perfectly.
>
> I then install TI's UBL and u-boot.bin to a Micron NAND flash
> (MT29F16G08) using TI's sfh_DM36x.exe flashing utility. I set up the
> u-boot environment and boot the kernel, which I compiled from TI's
> DVSDK.
>
> Everything boots up fine, except for access to the /dev/mtd? devices.
> Also /proc/mtd exists but is empty of devices - it should show the
> partitions of the flash chip. Further investigation reveals that the
> davinci_nand driver simply returns from platform_driver_probe() with a
> ENODEV "No such device" error.
>
> What is the device that is missing, and why does it go missing when I
> boot with this u-boot?  What makes some versions of u-boot activate this
> device in the kernel and others not?  What is the mechanism by which
> u-boot can do such a thing? It seems to be something other than simple
> kernel command line parameters. How do I begin even looking for this
> problem?
>
> I hope you can help. Any pointers would be greatly appreciated.

To be clear - you have used other versions of U-Boot on this board
that do properly report the NAND device?  If so, what version and
where did you get it?

I'd suspect that your board configuration is not causing the NAND
PINMUX to be set up correctly, hence Linux can't talk to the device.

-- 
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Gary Thomas                 |  Consulting for the
MLB Associates              |    Embedded world
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