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From: Philip Balister <philip@balister.org>
To: Tony Lindgren <tony@atomide.com>
Cc: "linux-omap@vger.kernel.org" <linux-omap@vger.kernel.org>
Subject: Re: DMA example
Date: Wed, 24 Feb 2010 14:31:09 -0800	[thread overview]
Message-ID: <4B85A8AD.5060206@balister.org> (raw)
In-Reply-To: <20100224203555.GT28173@atomide.com>

On 02/24/2010 12:35 PM, Tony Lindgren wrote:
> * Philip Balister<philip@balister.org>  [100224 11:31]:
>> I am trying to setup a dma operation to copy memory from GPMC
>> address space into RAM. The only examples using the omap-dma api use
>> hardware triggers.
>>
>> When I start a transfer, I end up with a DMA transaction error when
>> I start the transfer.
>>
>> Does anyone have a good example of a software transfer? Currently, I
>> am tracing the omap dma api to see how things map into the registers
>> ....
>
> Enjoy the GPMC timings. I recommend attaching a logic analyzer there
> to verify the things are right for the key lines if you have chance.
>
> Hmm I thought the hardware triggers were optional in at least
> drivers/usb/musb/tusb6010_omap.c.. Maybe I don't remember correctly.

GPMC is easy :)

Basically, I have a device attached to a GPMC chip select and I need to 
read/write to it. The GPNC bit is fine, we'd just like to use the DMA 
controller to move the data.

Philip

  reply	other threads:[~2010-02-24 22:31 UTC|newest]

Thread overview: 9+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2010-02-24 19:34 DMA example Philip Balister
2010-02-24 20:35 ` Tony Lindgren
2010-02-24 22:31   ` Philip Balister [this message]
2010-02-24 22:52     ` Tony Lindgren
2010-02-25  2:24       ` Philip Balister
2010-02-25  4:26         ` Philip Balister
2010-02-25  4:59           ` Shilimkar, Santosh
2010-02-25  6:22         ` Venkatraman S
2010-02-24 20:48 ` Shilimkar, Santosh

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