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

[Bin Meng]

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));

>  }
>
>  static inline void macb_invalidate_rx_buffer(struct macb_device *macb)
>  {
>         invalidate_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));
>  }
>
>  #if defined(CONFIG_CMD_NET)
> --

Regards,
Bin