From: Frank Li
> From: Fugang Duan <[email protected]>
> 
> Since enet-avb has 64 bytes alignment limitation for rx DMA transfer.
> The previous enet IP for ARM platform has 16 bytes alignment for tx
> DMA transfer.

Do you mean rx or tx here? or both??

And can we beat up the hardware designers to stop these restrictions
on rx (in particular) ethernet buffer alignments?
A device isn't suitable for ethernet unless is can write the destination
mac address to a 4n+2 boundary.

        David

> 64 is the an integral number of 16, so change alignment
> to 64 bytes for all ARM platform, which don't impact the performance
> of previous platform.
> 
> Signed-off-by: Fugang Duan <[email protected]>
> Signed-off-by: Frank Li <[email protected]>
> ---
>  drivers/net/ethernet/freescale/fec_main.c | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
> 
> diff --git a/drivers/net/ethernet/freescale/fec_main.c 
> b/drivers/net/ethernet/freescale/fec_main.c
> index a232245..b388e29f 100644
> --- a/drivers/net/ethernet/freescale/fec_main.c
> +++ b/drivers/net/ethernet/freescale/fec_main.c
> @@ -65,7 +65,7 @@
>  static void set_multicast_list(struct net_device *ndev);
> 
>  #if defined(CONFIG_ARM)
> -#define FEC_ALIGNMENT        0xf
> +#define FEC_ALIGNMENT        0x3f
>  #else
>  #define FEC_ALIGNMENT        0x3
>  #endif
> --
> 1.9.1
> 
> --
> To unsubscribe from this list: send the line "unsubscribe netdev" in
> the body of a message to [email protected]
> More majordomo info at  http://vger.kernel.org/majordomo-info.html


--
To unsubscribe from this list: send the line "unsubscribe devicetree" in
the body of a message to [email protected]
More majordomo info at  http://vger.kernel.org/majordomo-info.html

Reply via email to