Re: [PATCH v2 3/3] usb/hcd-xhci: Split pci wrapper for xhci base model

[Markus Armbruster]

Sai Pavan Boddu <saipava@xilinx.com> writes:

> HI Markus,
>
>> -----Original Message-----
>> From: Markus Armbruster <armbru@redhat.com>
>> Sent: Friday, June 26, 2020 11:42 AM
>> To: Sai Pavan Boddu <saipava@xilinx.com>
>> Cc: Peter Maydell <peter.maydell@linaro.org>; Thomas Huth
>> <thuth@redhat.com>; Eduardo Habkost <ehabkost@redhat.com>; qemu-
>> devel@nongnu.org; Alistair Francis <alistair.francis@wdc.com>; Gerd
>> Hoffmann <kraxel@redhat.com>; Paolo Bonzini <pbonzini@redhat.com>;
>> Ying Fang <fangying1@huawei.com>; 'Marc-André Lureau'
>> <marcandre.lureau@redhat.com>; 'Philippe Mathieu-Daudé'
>> <philmd@redhat.com>
>> Subject: Re: [PATCH v2 3/3] usb/hcd-xhci: Split pci wrapper for xhci base
>> model
>> 
>> Sai Pavan Boddu <saipava@xilinx.com> writes:
>> 
>> > Hi Markus,
>> >
>> >> -----Original Message-----
>> >> From: Markus Armbruster <armbru@redhat.com>
>> >> Sent: Thursday, June 25, 2020 1:42 PM
>> >> To: Sai Pavan Boddu <saipava@xilinx.com>
>> >> Cc: Gerd Hoffmann <kraxel@redhat.com>; Peter Maydell
>> >> <peter.maydell@linaro.org>; Thomas Huth <thuth@redhat.com>;
>> Eduardo
>> >> Habkost <ehabkost@redhat.com>; qemu-devel@nongnu.org; Alistair
>> >> Francis <alistair.francis@wdc.com>; 'Marc-André Lureau'
>> >> <marcandre.lureau@redhat.com>; Ying Fang <fangying1@huawei.com>;
>> >> Paolo Bonzini <pbonzini@redhat.com>; 'Philippe Mathieu-Daudé'
>> >> <philmd@redhat.com>
>> >> Subject: Re: [PATCH v2 3/3] usb/hcd-xhci: Split pci wrapper for xhci
>> >> base model
>> >>
>> >> Sai Pavan Boddu <sai.pavan.boddu@xilinx.com> writes:
>> >>
>> >> > This patch sets the base to use xhci as sysbus model, for which pci
>> >> > specific hooks are moved to hcd-xhci-pci.c. As a part of this
>> >> > requirment msi/msix interrupts handling is moved under
>> >> > XHCIPCIState, and XHCIState is  non qom object, make use of
>> >> > 'container_of' calls to retrive XHCIPciState. Made required changes for
>> qemu-xhci-nec.
>> >> >
>> >> > Signed-off-by: Sai Pavan Boddu <sai.pavan.boddu@xilinx.com>
>> >>
>> >> I can't see a "sysbus model".  What I can see is
>> >>
>> >>          TYPE_DEVICE
>> >>               |
>> >>        TYPE_PCI_DEVICE
>> >>               |
>> >>         TYPE_XHCI_PCI (renamed from TYPE_XHCI)
>> >>           /       \
>> >> TYPE_QEMU_XHCI TYPE_NEC_XHCI
>> >>
>> >> All but the two leaves are abstract.
>> >>
>> >> Do you intend to add a "sysbus model" in a future patch?
>> > [Sai Pavan Boddu]  Yes. I would be sending it along with that a device
>> > which would be using it. (i.e for zynqmp soc ) Let me know, if its good to
>> include hcd-xhci-sysbus.c here ?
>> 
>> I'm not sure this series is worthwhile this future patch.  Up to the 
>> maintainer.
>> 
>> Here's a clean way to provide different bus connectors (say PCI and
>> sysbus) for the same core device:
>> 
>> Make the core device a TYPE_DEVICE.
>> 
>> For each desired bus, have a bus-specific device that contains a core device.
>> Use object_initialize_child() for the component.
> [Sai Pavan Boddu] This was my V1 implementation.
> Changed it to non-qom structure after some feedback from @Gred. Felt like 
> XHCIState will not be used standalone.

I'll gladly defer to Gerd's judgement here.