[PATCH v3 for 3.10] Introduce a Marvell EBU MBus driver

[Neil Greatorex]

Ryan,

On Wed, 27 Mar 2013, Ryan Press wrote:

> Hi Neil,
>
> On Wed, Mar 27, 2013 at 6:32 PM, Neil Greatorex <neil at fatboyfat.co.uk> wrote:
>> Thomas,
>>
>> This set of patches seems to break the mvsdio driver (and hence
>> mwifiex_sdio) on the Globalscale Mirabox. I believe this is because
>> mvsdio.c contains a function mv_conf_mbus_windows that seems to
>> conflict with the new mbus driver. I don't understand enough about the
>> hardware (without the datasheets anyway) to be able to understand the
>> exact problem, but I hope that this is enough to point you (or someone
>> else) to it!
>
> I've been working on getting my Mirabox running with the mainline
> kernel.  There seems to be a problem with DMA and the mvsdio driver,
> which causes the exact same dmesg for me.  Try loading the mvsdio
> driver like so: "modprobe mvsdio nodma=1" and then modprobe the
> mwifiex_sdio driver and see if it works for you too.
>
> Ryan
>

Thanks for the information. Yes that does fix the issue, because the 
mvsdio driver then no longer needs to use the SDRAM address windows to do 
DMA transfers. However, it turns out that by doing this you are masking 
the bug that what actually introduced in the mbus driver (see my earlier 
reply to Thomas). Still, this does mean that the wifi adapter actually 
works now as even with the mbus fix it's unreliable, so thanks.

Cheers,
Neil