[PATCH net-next V2 08/16] net: fec: eliminate calls to fec_enet_get_prevdesc

[Fugang Duan]

From: Troy Kisky <troy.kisky at boundarydevices.com> Sent: Thursday, February 25, 2016 8:37 AM
> To: netdev at vger.kernel.org; davem at davemloft.net; b38611 at freescale.com
> Cc: fabio.estevam at freescale.com; l.stach at pengutronix.de; andrew at lunn.ch;
> tremyfr at gmail.com; linux at arm.linux.org.uk; linux-arm-
> kernel at lists.infradead.org; laci at boundarydevices.com; shawnguo at kernel.org;
> johannes at sipsolutions.net; stillcompiling at gmail.com;
> sergei.shtylyov at cogentembedded.com; arnd at arndb.de; Troy Kisky
> <troy.kisky at boundarydevices.com>
> Subject: [PATCH net-next V2 08/16] net: fec: eliminate calls to
> fec_enet_get_prevdesc
> 
> This shrinks the code a little.
> 
> Signed-off-by: Troy Kisky <troy.kisky at boundarydevices.com>
> ---
>  drivers/net/ethernet/freescale/fec_main.c | 37 +++++++++----------------------
>  1 file changed, 11 insertions(+), 26 deletions(-)
> 
> diff --git a/drivers/net/ethernet/freescale/fec_main.c
> b/drivers/net/ethernet/freescale/fec_main.c
> index 6ceb5f9..b5ed287 100644
> --- a/drivers/net/ethernet/freescale/fec_main.c
> +++ b/drivers/net/ethernet/freescale/fec_main.c
> @@ -758,6 +758,7 @@ static void fec_enet_bd_init(struct net_device *dev)
>  	struct bufdesc *bdp;
>  	unsigned int i;
>  	unsigned int q;
> +	unsigned status;

Should be unsigned int status;

> 
>  	for (q = 0; q < fep->num_rx_queues; q++) {
>  		/* Initialize the receive buffer descriptors. */ @@ -765,19
> +766,13 @@ static void fec_enet_bd_init(struct net_device *dev)
>  		bdp = rxq->bd.base;
> 
>  		for (i = 0; i < rxq->bd.ring_size; i++) {
> -
>  			/* Initialize the BD for every fragment in the page. */
> -			if (bdp->cbd_bufaddr)
> -				bdp->cbd_sc =
> cpu_to_fec16(BD_ENET_RX_EMPTY);
> -			else
> -				bdp->cbd_sc = cpu_to_fec16(0);
> +			status = bdp->cbd_bufaddr ? BD_ENET_RX_EMPTY : 0;
> +			if (bdp == rxq->bd.last)
> +				status |= BD_SC_WRAP;
> +			bdp->cbd_sc = cpu_to_fec16(status);
>  			bdp = fec_enet_get_nextdesc(bdp, &rxq->bd);
>  		}
> -
> -		/* Set the last buffer to wrap */
> -		bdp = fec_enet_get_prevdesc(bdp, &rxq->bd);
> -		bdp->cbd_sc |= cpu_to_fec16(BD_SC_WRAP);
> -
>  		rxq->bd.cur = rxq->bd.base;
>  	}
> 
> @@ -789,18 +784,16 @@ static void fec_enet_bd_init(struct net_device *dev)
> 
>  		for (i = 0; i < txq->bd.ring_size; i++) {
>  			/* Initialize the BD for every fragment in the page. */
> -			bdp->cbd_sc = cpu_to_fec16(0);
>  			if (txq->tx_skbuff[i]) {
>  				dev_kfree_skb_any(txq->tx_skbuff[i]);
>  				txq->tx_skbuff[i] = NULL;
>  			}
>  			bdp->cbd_bufaddr = cpu_to_fec32(0);
> +			bdp->cbd_sc = cpu_to_fec16((bdp == txq->bd.last) ?
> +					BD_SC_WRAP : 0);
>  			bdp = fec_enet_get_nextdesc(bdp, &txq->bd);
>  		}
> -
> -		/* Set the last buffer to wrap */
>  		bdp = fec_enet_get_prevdesc(bdp, &txq->bd);
> -		bdp->cbd_sc |= cpu_to_fec16(BD_SC_WRAP);
>  		txq->dirty_tx = bdp;
>  	}
>  }
> @@ -2717,19 +2710,16 @@ fec_enet_alloc_rxq_buffers(struct net_device
> *ndev, unsigned int queue)
>  		}
> 
>  		rxq->rx_skbuff[i] = skb;
> -		bdp->cbd_sc = cpu_to_fec16(BD_ENET_RX_EMPTY);
> 
>  		if (fep->bufdesc_ex) {
>  			struct bufdesc_ex *ebdp = (struct bufdesc_ex *)bdp;
>  			ebdp->cbd_esc = cpu_to_fec32(BD_ENET_RX_INT);
>  		}
> +		bdp->cbd_sc = cpu_to_fec16(BD_ENET_RX_EMPTY |
> +				((bdp == rxq->bd.last) ? BD_SC_WRAP : 0));
> 
>  		bdp = fec_enet_get_nextdesc(bdp, &rxq->bd);
>  	}
> -
> -	/* Set the last buffer to wrap. */
> -	bdp = fec_enet_get_prevdesc(bdp, &rxq->bd);
> -	bdp->cbd_sc |= cpu_to_fec16(BD_SC_WRAP);
>  	return 0;
> 
>   err_alloc:
> @@ -2752,21 +2742,16 @@ fec_enet_alloc_txq_buffers(struct net_device
> *ndev, unsigned int queue)
>  		if (!txq->tx_bounce[i])
>  			goto err_alloc;
> 
> -		bdp->cbd_sc = cpu_to_fec16(0);
>  		bdp->cbd_bufaddr = cpu_to_fec32(0);
> 
>  		if (fep->bufdesc_ex) {
>  			struct bufdesc_ex *ebdp = (struct bufdesc_ex *)bdp;
>  			ebdp->cbd_esc = cpu_to_fec32(BD_ENET_TX_INT);
>  		}
> -
> +		bdp->cbd_sc = cpu_to_fec16((bdp == txq->bd.last) ?
> +				BD_SC_WRAP : 0);
>  		bdp = fec_enet_get_nextdesc(bdp, &txq->bd);
>  	}
> -
> -	/* Set the last buffer to wrap. */
> -	bdp = fec_enet_get_prevdesc(bdp, &txq->bd);
> -	bdp->cbd_sc |= cpu_to_fec16(BD_SC_WRAP);
> -
>  	return 0;
> 
>   err_alloc:
> --
> 2.5.0