USB support on mpc5200 broken

Jon Smirl jonsmirl at gmail.com
Tue Sep 30 07:04:22 EST 2008


On Mon, Sep 29, 2008 at 4:18 PM, Scott Wood <scottwood at freescale.com> wrote:
> On Mon, Sep 29, 2008 at 10:14:18AM -0400, Jon Smirl wrote:
>> Shouldn't the driver already know it is being used on a BE machine?
>
> No.  Endianness of the CPU is not necessarily the same as the endianness
> of device registers.
>
> For example, PCI OHCI on a big-endian host.

Endianess is encoded in the specific compatible string.

compatible = "fsl,mpc5200b-ohci","fsl,mpc5200-ohci";
This is BE.

inside PCI bus section
compatible = "my-pci-ohci-card"
This would be LE

The specifically loaded driver knows it's endianess.

But now you're tell me I need
compatible = "fsl,mpc5200b-ohci","fsl,mpc5200-ohci",  "ohci-be"

But that doesn't work right on the mpc5200. If I remove the mpc5200
specific device driver from my system it will cause the generic
ohci-be one to load. And the generic one doesn't work.

The mpc5200 ohci device driver should be setting the endianess state
into the generic ohci code.


>
> -Scott
>



-- 
Jon Smirl
jonsmirl at gmail.com



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