Re: [Qemu-devel] [PATCH] net: cadence_gem: clear RX control descriptor

[Ramon Fried <rfried.dev@gmail.com>]

On Tue, Jul 16, 2019 at 11:42 AM Jason Wang <jasowang@redhat.com> wrote:
>
>
> On 2019/6/15 下午1:17, Ramon Fried wrote:
> > The RX ring descriptors control field is used for setting
> > SOF and EOF (start of frame and end of frame).
> > The SOF and EOF weren't cleared from the previous descriptors,
> > causing inconsistencies in ring buffer.
> > Fix that by clearing the control field of every descriptors we're
> > processing.
> >
> > Signed-off-by: Ramon Fried <rfried.dev@gmail.com>
> > ---
> >   hw/net/cadence_gem.c | 7 +++++++
> >   1 file changed, 7 insertions(+)
> >
> > diff --git a/hw/net/cadence_gem.c b/hw/net/cadence_gem.c
> > index ecee22525c..d83a82bdb0 100644
> > --- a/hw/net/cadence_gem.c
> > +++ b/hw/net/cadence_gem.c
> > @@ -406,6 +406,11 @@ static inline void rx_desc_set_sof(uint32_t *desc)
> >       desc[1] |= DESC_1_RX_SOF;
> >   }
> >
> > +static inline void rx_desc_clear(uint32_t *desc)
>
>
> Nit: is this better to name this as "rx_desc_clear_control()" ?
I agree, sent v2.
>
> Thanks
>
>
> > +{
> > +    desc[1]  = 0;
> > +}
> > +
> >   static inline void rx_desc_set_eof(uint32_t *desc)
> >   {
> >       desc[1] |= DESC_1_RX_EOF;
> > @@ -994,6 +999,8 @@ static ssize_t gem_receive(NetClientState *nc, const uint8_t *buf, size_t size)
> >           bytes_to_copy -= MIN(bytes_to_copy, rxbufsize);
> >
> >           /* Update the descriptor.  */
> > +        rx_desc_clear(s->rx_desc[q]);
> > +
> >           if (first_desc) {
> >               rx_desc_set_sof(s->rx_desc[q]);
> >               first_desc = false;
>
>
>