[U-Boot] [PATCH] net: macb: Fix rx buffer cache handling

[Ramon Fried]

On Fri, Aug 23, 2019 at 1:37 PM Stefan Roese <sr at denx.de> wrote:
>
> Hi Bin,
>
> On 23.08.19 11:22, Bin Meng wrote:
> > On Fri, Aug 23, 2019 at 5:17 PM Bin Meng <bmeng.cn at gmail.com> wrote:
> >>
> >> Hi Stefan,
> >>
> >> On Fri, Aug 23, 2019 at 5:02 PM Stefan Roese <sr at denx.de> wrote:
> >>>
> >>> With commit c6d07bf440bc ("net/macb: increase RX buffer size for GEM")
> >>> ethernet support does not work any more with d-cache enabled on the
> >>> AT91SAM. The reason is, that MACB_RX_BUFFER_SIZE was changed from 4096
> >>> to 128 but this change was not refected in the rx_buffer flush and
> >>> invalidate functions, as these also use this macro.
> >>>
> >>> This patch now fixes this by calculating the rx buffer size correctly
> >>> again in those functions. With this change, ethernet works again
> >>> reliably on my AT91SAM board.
> >>>
> >>> Signed-off-by: Stefan Roese <sr at denx.de>
> >>> Cc: Ramon Fried <rfried.dev at gmail.com>
> >>> Cc: Eugen Hristev <eugen.hristev at microchip.com>
> >>> Cc: Anup Patel <anup.patel at wdc.com>
> >>> Cc: Bin Meng <bmeng.cn at gmail.com>
> >>> Cc: Joe Hershberger <joe.hershberger at ni.com>
> >>> ---
> >>>   drivers/net/macb.c | 6 ++++--
> >>>   1 file changed, 4 insertions(+), 2 deletions(-)
> >>>
> >>> diff --git a/drivers/net/macb.c b/drivers/net/macb.c
> >>> index c99cf663a4..fca380d012 100644
> >>> --- a/drivers/net/macb.c
> >>> +++ b/drivers/net/macb.c
> >>> @@ -296,13 +296,15 @@ static inline void macb_flush_ring_desc(struct macb_device *macb, bool rx)
> >>>   static inline void macb_flush_rx_buffer(struct macb_device *macb)
> >>>   {
> >>>          flush_dcache_range(macb->rx_buffer_dma, macb->rx_buffer_dma +
> >>> -                          ALIGN(MACB_RX_BUFFER_SIZE, PKTALIGN));
> >>> +                          ALIGN(MACB_RX_BUFFER_SIZE * MACB_RX_RING_SIZE,
> >>> +                                PKTALIGN));
> >>
> >> This looks wrong to me.
> >>
> >> Shouldn't it be:
> >>
> >>           flush_dcache_range(macb->rx_buffer_dma, macb->rx_buffer_dma +
> >>                            ALIGN(macb->rx_buffer_size, PKTALIGN));
> >
> > Ah, for MACB, looks it should be "MACB_RX_BUFFER_SIZE *
> > MACB_RX_RING_SIZE", but for GEM, I am not sure.
> >
> > Should it be:
> >
> >            flush_dcache_range(macb->rx_buffer_dma, macb->rx_buffer_dma +
> >                             ALIGN(macb->rx_buffer_size *
> > MACB_RX_RING_SIZE, PKTALIGN));
>
> Yes, this looks correct. v2 will follow soon.
>
> Thanks,
> Stefan

Thanks Stefan,
Can you fix your commit message to show: Fixes:...

You can use the following bash alias to generate the line: (pass
c6d07bf440bc as argument)
alias gfixes='git --no-pager show -s --abbrev-commit --abbrev=12
--pretty=format:"Fixes: %h (\"%s\")%n"'