Re: [Qemu-devel] [PATCH 1/2] vfio/platform: make the vfio-platform device non abstract

[Sinan Kaya]

On 2/21/2017 10:23 AM, Auger Eric wrote:
>> Note that the goal is to be able to instantiate any platform device by just
>> passing a compatible string and the object from the host. We don't want
>> to make changes to QEMU every time somebody comes up with a new platform 
>> device.
>> This step is unnecessary.
> Well we need to generate a device tree node for your device. We have not
> proven yet the function that creates this latter can be generic. There
> are some helpers that can read the host dt node, copy some properties
> from the host to the guest. But still at the moment we can't make things
> as generic as PCIe and this is why the platform passthrough still is
> controversial. So this patch aims at lowering the integration efforts
> but minimal specialization needs to be done in sysbus-fdt. Same on
> kernel side with the reset module.

Understood. You need to bring in the entire device tree parameters for a 
full-blown
solution. We can always treat this as a TODO.

I was more interested in simple devices like XHCI, AHCI, HIDMA where there
is no platform device attribute besides the interrupt number and memory
resources. QEMU already has access to these.

I was hoping to cover this at least. More complex objects need their own
implementation like the AMD driver in your example.

I'm pasting my comment from the archives here. 

https://lists.gnu.org/archive/html/qemu-devel/2016-08/msg03267.html

"Why submit a new SATA AHCI driver for QEMU just to set the compat string?"


> 
> Thanks
> 
> Eric
> 
> 


-- 
Sinan Kaya
Qualcomm Datacenter Technologies, Inc. as an affiliate of Qualcomm 
Technologies, Inc.
Qualcomm Technologies, Inc. is a member of the Code Aurora Forum, a Linux 
Foundation Collaborative Project.