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Subject: Re: [Qemu-devel] [RFC 03/10] AHCI: Add PRD interrupt
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To: Paolo Bonzini <pbonzini@redhat.com>, qemu-devel@nongnu.org
Cc: stefanha@redhat.com, mst@redhat.com



On 09/13/2014 03:50 PM, Paolo Bonzini wrote:
> Il 13/09/2014 15:26, Paolo Bonzini ha scritto:
>>>>
>>>> +    if (ad->dp_intr_req) {
>>>> +        ahci_trigger_irq(ad->hba, ad, PORT_IRQ_SG_DONE);
>>>> +        ad->dp_intr_req = 0;
>>>> +    }
>> Is it also needed in the error case?  Especially the short-PRDT case
>> that you are adding in the next patch.
>>
>
> ... and is it also needed for NCQ, albeit with a separate flag?
>
> Paolo
>

I had actually thought that it wasn't; due to the more asynchronous 
nature of NCQ. But... looking back at the specification, I can't find 
anywhere that explicitly says you can't use these bits for NCQ.