On Thu, Sep 26, 2024 at 11:50:32AM +0800, Jason Wang wrote: > On Thu, Sep 26, 2024 at 11:31 AM Jianguo Sun (QUIC) > <quic_jiang...@quicinc.com> wrote: > > > > Hi @Jason > > > > Both hypervisor and backend device may need to support virtio-mmio device > > reset > > Then you need to patch the virtio spec first. Or it is already > supported by the spec? > > > Adding CONFIG_VIRTIO_MMIO_POLL_RESET is for the system that has such > > support. > > And we will probably have a feature or transport bit/flag for this. > > Thanks
feature bits can't affect reset. I don't know what a transport bit/flag is, in the context of MMIO. We can just make it a recommendation. > > > > A config option (feature bit) is a better approach. > > Thanks for the review. > > > > BR > > Jianguo > > > > -----Original Message----- > > From: Jason Wang <jasow...@redhat.com> > > Sent: Tuesday, September 24, 2024 3:39 PM > > To: Jianguo Sun (QUIC) <quic_jiang...@quicinc.com> > > Cc: m...@redhat.com; xuanz...@linux.alibaba.com; epere...@redhat.com; > > virtualization@lists.linux.dev; Anant Goel (QUIC) <quic_ana...@quicinc.com> > > Subject: Re: [PATCH 1/2] Virtio: Add CONFIG_VIRTIO_MMIO_POLL_RESET > > > > On Sun, Sep 22, 2024 at 8:35 PM Jianguo Sun <quic_jiang...@quicinc.com> > > wrote: > > > > > > Add CONFIG_VIRTIO_MMIO_POLL_RESET to as an option to enable > > > synchronous reset for the MMIO based transport for virtio. > > > > > > Change-Id: Ifa7e29b4c0cfa26922535f921c6ab69eacdc4cfc > > > Signed-off-by: Jianguo Sun <quic_jiang...@quicinc.com> > > > Signed-off-by: Anant Goel <quic_ana...@quicinc.com> > > > > Any reason this is not a feature but a config option? > > > > > --- > > > drivers/virtio/Kconfig | 8 ++++++++ > > > 1 file changed, 8 insertions(+) > > > > > > diff --git a/drivers/virtio/Kconfig b/drivers/virtio/Kconfig index > > > 42a48ac763ee..fb17b1078d53 100644 > > > --- a/drivers/virtio/Kconfig > > > +++ b/drivers/virtio/Kconfig > > > @@ -188,4 +188,12 @@ config VIRTIO_DEBUG > > > > > > If unsure, say N. > > > > > > +config VIRTIO_MMIO_POLL_RESET > > > + bool "Virti-mmio device synchronous reset support" > > > + depends on VIRTIO_MMIO > > > + help > > > + Say y here to enable synchronous reset for the MMIO transport > > > based > > > + virtio device. After writing 0 to device_status, the driver must > > > + wait for a read of device_status to return 0 before > > > reinitializing > > > + the device. > > > endif # VIRTIO_MENU > > > -- > > > 2.17.1 > > > > > > > Thanks > >
