Re: [Qemu-arm] [Qemu-devel] [PATCH RFC 1/2] Increased the size of requester_id field from MemTxAttrs

[Diana Madalina Craciun]

On 04/04/2017 03:27 PM, Peter Maydell wrote:
> On 23 March 2017 at 13:36, Diana Craciun <address@hidden> wrote:
>> The PCI requester ID field is 16 bits. The requester_id field
>> from MemTxAttrs is used for MSIs to specify the device ID for
>> the platforms where this device ID is needed (e.g virt machine + GICv3
>> ITS). However, if more entities that uses MSIs in the system are used,
>> 16 bit is no longer enough to represent the device ID. Increased the size
>> of this field to 24 bits in order to accomodate 256 entities.
>> Also the name requester_id does no longer reflect the content, so
>> the name was changed to stream_id.
> This name change would be reverting the name change in
> commit a05f686ff3, which says:
>     MemTxAttrs.stream_id also renamed to requester_id in order to better
>     reflect semantics of the field.
>
> I don't have a strong opinion about the name myself, but flipping
> backwards and forwards doesn't seem like a great plan :-)

The reason I have changed the name is that the requester_id is a PCI
related terminology and this patch is extending the usage of that field
to other devices also. Naming it requester_id might be confusing.

I will shortly send a v2 for the patches, I didn't change the name in
the v2, but if there are strong opinions regarding this naming, I will
change it.

Thanks,

Diana