[U-Boot] [PATCH] ppc4xx/POST: Change ethernet test loop count from 192 to 16

[Wolfgang Denk]

Dear Stefan Roese,

In message <1290782654-9242-1-git-send-email-sr at denx.de> you wrote:
> This patch changes the PPC4xx ethernet POST loop test count from
> currently 192 (256 - 64) to 16 which should be enough. The main reason
> for this is to reduce the boot time on boards using this POST test,
> like the lwmon5 board. This change reduces the boot time by about
> 600ms on the lwmon5 board.
> 
> Signed-off-by: Stefan Roese <sr at denx.de>
> ---
>  post/cpu/ppc4xx/ether.c |    4 ++--
>  1 files changed, 2 insertions(+), 2 deletions(-)
> 
> diff --git a/post/cpu/ppc4xx/ether.c b/post/cpu/ppc4xx/ether.c
> index 7f44f38..1593a8d 100644
> --- a/post/cpu/ppc4xx/ether.c
> +++ b/post/cpu/ppc4xx/ether.c
> @@ -76,8 +76,8 @@ DECLARE_GLOBAL_DATA_PTR;
>  #define SDR0_MFR_ETH_CLK_SEL_V(n)	((0x01<<27) / (n+1))
>  #endif
>  
> -#define MIN_PACKET_LENGTH	64
> -#define MAX_PACKET_LENGTH	256
> +#define MIN_PACKET_LENGTH	256
> +#define MAX_PACKET_LENGTH	(256 + 16)

Maybe it does indeed make sense to test a wider range of package
sizes.  Actually I'd even like to see longer packets tested as well.

How about:

	#define MIN_PACKET_LENGTH    64
	#define MAX_PACKET_LENGTH    1518

and changing the

	for (l = MIN_PACKET_LENGTH; l <= MAX_PACKET_LENGTH; l++) {
into
	for (l = MIN_PACKET_LENGTH; l <= MAX_PACKET_LENGTH; l+=91) {

Then you still have 16 tests, but with a much wider range of packet
sizes (64...1429).

Best regards,

Wolfgang Denk

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