From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Subject: Re: [virtio-dev] [PATCH] virtio-mmio: Specify wait needed in driver during reset From: Srivatsa Vaddagiri Date: Thu, 22 Jul 2021 15:41:49 +0000 Message-ID: References: <87pmva7h06.fsf@redhat.com>, In-Reply-To: MIME-Version: 1.0 Content-Language: en-US Content-Type: multipart/alternative; boundary="_000_BY5PR02MB7073E8361281BB624E320FA4F9E49BY5PR02MB7073namp_" To: Jason Wang , Cornelia Huck , "mst@redhat.com" , "virtio-dev@lists.oasis-open.org" Cc: Trilok Soni , Pratik Patel List-ID: --_000_BY5PR02MB7073E8361281BB624E320FA4F9E49BY5PR02MB7073namp_ Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable > >> I wonder if it deserves a feature bit. > > Not sure what that feature bit should govern; if it is not negotiated, > > the device must assume that the driver considers the reset to be > > complete right after writing? I'm not sure what the device is supposed > > to do then. > > > The (hardware) device can refuse the feature negotiation if driver > doesn't support the feature. > > This makes sure the driver is not broken by the device. Let me send the next patch with a new feature bit added. I guess I can use = bit 40 for it (VIRTIO_F_MMIO_RESET_WAIT)? - vatsa --- Qualcomm Innovation Center, Inc. is submitting the attached "feedback" as a non-member to the virtio-dev mailing list for consideration and inclusion. --_000_BY5PR02MB7073E8361281BB624E320FA4F9E49BY5PR02MB7073namp_ Content-Type: text/html; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable
> >> I wonder if it deserves a feature bit.
> > Not sure what that feature bit should govern; if it is not n= egotiated,
> > the device must assume that the driver considers the reset t= o be
> > complete right after writing? I'm not sure what the device i= s supposed
> > to do then.
>
>
> The (hardware) device can refuse the feature negotiation if drive= r
> doesn't support the feature.
>
> This makes sure the driver is not broken by the device.

Let me send the next patch with a new feature bit added. I guess I can= use bit
40 for it (VIRTIO_F_MMIO_RESET_WAIT)?

- vatsa

---

Qualcomm Innovation Center, Inc. is submitting the attached "feed= back" as a
non-member to the virtio-dev mailing list for consideration and inclu= sion.
--_000_BY5PR02MB7073E8361281BB624E320FA4F9E49BY5PR02MB7073namp_--