[PATCH v2 2/2] Crypto: Talitos: Support for Async_tx XOR offload

Li Yang-R58472 r58472 at freescale.com
Sat Dec 19 02:02:22 EST 2009


>Subject: Re: [PATCH v2 2/2] Crypto: Talitos: Support for 
>Async_tx XOR offload
>
>Ira W. Snyder wrote:
>> Yes, I have used the device_prep_dma_interrupt() 
>functionality quite a 
>> while back. However, I found it to be pretty much useless.
>
>The specific case it is needed for Talitos/raid is a channel 
>switch interrupt.  The interrupt causes the cleanup operation 
>to be run which will kick off any pending dependent operations 
>on the xor channel.  In the raid case we only have callbacks 
>at the end of a chain, so we need the interrupt to kick the 
>engine in an operation chain like 
>xor->copy->xor->callback.

I am wondering if can use more callbacks to kick off pending dependent operations?
Like xor->callback->copy->callback->xor->callback?

- Leo


More information about the Linuxppc-dev mailing list