Re: [Qemu-devel] [PATCH 08/11] s390x/flic: introduce modify_ais_mode callback

[Cornelia Huck <cohuck@redhat.com>]

On Thu, 13 Jul 2017 09:35:16 +0200
Christian Borntraeger <borntraeger@de.ibm.com> wrote:

> On 07/13/2017 09:27 AM, Cornelia Huck wrote:
> > On Thu, 13 Jul 2017 09:12:50 +0200
> > Christian Borntraeger <borntraeger@de.ibm.com> wrote:
> >   
> >> On 07/12/2017 05:07 PM, Cornelia Huck wrote:  
> >>>> +
> >>>> +    switch (mode) {
> >>>> +    case SIC_IRQ_MODE_ALL:
> >>>> +        flic->simm &= ~AIS_MODE_MASK(isc);
> >>>> +        flic->nimm &= ~AIS_MODE_MASK(isc);
> >>>> +        break;
> >>>> +    case SIC_IRQ_MODE_SINGLE:
> >>>> +        flic->simm |= AIS_MODE_MASK(isc);
> >>>> +        flic->nimm &= ~AIS_MODE_MASK(isc);    
> >>>
> >>> Can we have some documentation about the meaning of simm/nimm in qemu?
> >>> The one from the patch description of the respective kernel patch would
> >>> be fine.    
> >>
> >> Do you want to have that description as part of the patch description or
> >> somewhere in the docs folder or somewhere in the code?  
> > 
> > A comment near the definition of simm/nimm would be nice. Or in the
> > commit message, as for the kernel.
> >   
> 
> I  think I will just add this to the commit message:
> 
> We introduce the 'simm' and 'nimm' fields to QEMUS390FLICState
> to store interruption modes for each ISC. Each bit in 'simm' and
> 'nimm' targets to one ISC, and collaboratively indicate three modes:

s/targets to one/targets one/

> ALL-Interruptions, SINGLE-Interruption and NO-Interruptions. This
> interface can initiate most transitions between the states; transition
> from SINGLE-Interruption to NO-Interruptions via adapter interrupt
> injection will be introduced in a following patch. The meaningful
> combinations are as follows:
>     
>     interruption mode | simm bit | nimm bit
>     ------------------|----------|----------
>              ALL      |    0     |     0
>            SINGLE     |    1     |     0
>              NO       |    1     |     1
>     
> 
> 

Sounds good.