[U-Boot] [PATCH] tsec: Configure the buffer descriptor bases to always include all of the descriptors

[Joe Hershberger]

On Wed, Aug 10, 2011 at 7:29 AM, Detlev Zundel <dzu at denx.de> wrote:
>> diff --git a/drivers/net/tsec.c b/drivers/net/tsec.c
>> index 78ffc95..1805ca0 100644
>> --- a/drivers/net/tsec.c
>> +++ b/drivers/net/tsec.c
>> @@ -250,8 +250,8 @@ static void startup_tsec(struct eth_device *dev)
>>       txIdx = 0;
>>
>>       /* Point to the buffer descriptors */
>> -     out_be32(&regs->tbase, (unsigned int)(&rtx.txbd[txIdx]));
>> -     out_be32(&regs->rbase, (unsigned int)(&rtx.rxbd[rxIdx]));
>> +     out_be32(&regs->tbase, (unsigned int)(&rtx.txbd[0]));
>> +     out_be32(&regs->rbase, (unsigned int)(&rtx.rxbd[0]));
>>
>>       /* Initialize the Rx Buffer descriptors */
>>       for (i = 0; i < PKTBUFSRX; i++) {
>
> I see these two lines just before the code you change (one is even in
> the context of your patch):
>
>        /* reset the indices to zero */
>        rxIdx = 0;
>        txIdx = 0;
>
> So can you tell me, what your change actually does?  I cannot remember
> that we have concurrency issues here, or do we?

My apologies... I ported this patch from my work in u-boot 2009.11 and
did not notice that change above.  I think explicitly using 0 when
assigning the base address pointers is clearer, though.

It seems the resetting of the indexes to 0 was added by Andy Fleming
in 063c12633d5ad74d52152d9c358e715475e17629, though the log doesn't
discuss it..

Best regards,
-Joe