From mboxrd@z Thu Jan 1 00:00:00 1970 From: Troy Kisky Subject: [PATCH net-next V3 08/16] net: fec: set cbd_sc without relying on previous value Date: Tue, 5 Apr 2016 19:25:54 -0700 Message-ID: <1459909562-22865-9-git-send-email-troy.kisky@boundarydevices.com> References: <1459909562-22865-1-git-send-email-troy.kisky@boundarydevices.com> Cc: fabio.estevam@nxp.com, l.stach@pengutronix.de, andrew@lunn.ch, tremyfr@gmail.com, gerg@uclinux.org, linux-arm-kernel@lists.infradead.org, johannes@sipsolutions.net, stillcompiling@gmail.com, sergei.shtylyov@cogentembedded.com, arnd@arndb.de, Troy Kisky To: netdev@vger.kernel.org, davem@davemloft.net, fugang.duan@nxp.com, lznuaa@gmail.com Return-path: Received: from mail-pf0-f177.google.com ([209.85.192.177]:33030 "EHLO mail-pf0-f177.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1759981AbcDFC2X (ORCPT ); Tue, 5 Apr 2016 22:28:23 -0400 Received: by mail-pf0-f177.google.com with SMTP id 184so23189502pff.0 for ; Tue, 05 Apr 2016 19:28:22 -0700 (PDT) In-Reply-To: <1459909562-22865-1-git-send-email-troy.kisky@boundarydevices.com> Sender: netdev-owner@vger.kernel.org List-ID: Relying on the wrap bit of cdb_sc to stay valid once initialized when the controller also writes to this byte seems undesirable since we can easily know what the value should be. Signed-off-by: Troy Kisky --- v3: change commit message --- drivers/net/ethernet/freescale/fec_main.c | 38 +++++++++---------------------- 1 file changed, 11 insertions(+), 27 deletions(-) diff --git a/drivers/net/ethernet/freescale/fec_main.c b/drivers/net/ethernet/freescale/fec_main.c index 3cd0cdf..21d2cd0 100644 --- a/drivers/net/ethernet/freescale/fec_main.c +++ b/drivers/net/ethernet/freescale/fec_main.c @@ -340,9 +340,8 @@ fec_enet_txq_submit_frag_skb(struct fec_enet_priv_tx_q *txq, bdp = fec_enet_get_nextdesc(bdp, &txq->bd); ebdp = (struct bufdesc_ex *)bdp; - status = fec16_to_cpu(bdp->cbd_sc); - status &= ~BD_ENET_TX_STATS; - status |= (BD_ENET_TX_TC | BD_ENET_TX_READY); + status = BD_ENET_TX_TC | BD_ENET_TX_READY | + ((bdp == txq->bd.last) ? BD_SC_WRAP : 0); frag_len = skb_shinfo(skb)->frags[frag].size; /* Handle the last BD specially */ @@ -436,8 +435,6 @@ static int fec_enet_txq_submit_skb(struct fec_enet_priv_tx_q *txq, /* Fill in a Tx ring entry */ bdp = txq->bd.cur; last_bdp = bdp; - status = fec16_to_cpu(bdp->cbd_sc); - status &= ~BD_ENET_TX_STATS; /* Set buffer length and buffer pointer */ bufaddr = skb->data; @@ -462,6 +459,8 @@ static int fec_enet_txq_submit_skb(struct fec_enet_priv_tx_q *txq, return NETDEV_TX_OK; } + status = BD_ENET_TX_TC | BD_ENET_TX_READY | + ((bdp == txq->bd.last) ? BD_SC_WRAP : 0); if (nr_frags) { last_bdp = fec_enet_txq_submit_frag_skb(txq, skb, ndev); if (IS_ERR(last_bdp)) { @@ -512,7 +511,6 @@ static int fec_enet_txq_submit_skb(struct fec_enet_priv_tx_q *txq, /* Send it on its way. Tell FEC it's ready, interrupt when done, * it's the last BD of the frame, and to put the CRC on the end. */ - status |= (BD_ENET_TX_READY | BD_ENET_TX_TC); bdp->cbd_sc = cpu_to_fec16(status); /* If this was the last BD in the ring, start at the beginning again. */ @@ -544,11 +542,6 @@ fec_enet_txq_put_data_tso(struct fec_enet_priv_tx_q *txq, struct sk_buff *skb, unsigned int estatus = 0; dma_addr_t addr; - status = fec16_to_cpu(bdp->cbd_sc); - status &= ~BD_ENET_TX_STATS; - - status |= (BD_ENET_TX_TC | BD_ENET_TX_READY); - if (((unsigned long) data) & fep->tx_align || fep->quirks & FEC_QUIRK_SWAP_FRAME) { memcpy(txq->tx_bounce[index], data, size); @@ -578,15 +571,16 @@ fec_enet_txq_put_data_tso(struct fec_enet_priv_tx_q *txq, struct sk_buff *skb, ebdp->cbd_esc = cpu_to_fec32(estatus); } + status = BD_ENET_TX_TC | BD_ENET_TX_READY | + ((bdp == txq->bd.last) ? BD_SC_WRAP : 0); /* Handle the last BD specially */ if (last_tcp) - status |= (BD_ENET_TX_LAST | BD_ENET_TX_TC); + status |= BD_ENET_TX_LAST; if (is_last) { status |= BD_ENET_TX_INTR; if (fep->bufdesc_ex) ebdp->cbd_esc |= cpu_to_fec32(BD_ENET_TX_INT); } - bdp->cbd_sc = cpu_to_fec16(status); return 0; @@ -602,13 +596,8 @@ fec_enet_txq_put_hdr_tso(struct fec_enet_priv_tx_q *txq, struct bufdesc_ex *ebdp = container_of(bdp, struct bufdesc_ex, desc); void *bufaddr; unsigned long dmabuf; - unsigned short status; unsigned int estatus = 0; - status = fec16_to_cpu(bdp->cbd_sc); - status &= ~BD_ENET_TX_STATS; - status |= (BD_ENET_TX_TC | BD_ENET_TX_READY); - bufaddr = txq->tso_hdrs + index * TSO_HEADER_SIZE; dmabuf = txq->tso_hdrs_dma + index * TSO_HEADER_SIZE; if (((unsigned long)bufaddr) & fep->tx_align || @@ -641,8 +630,8 @@ fec_enet_txq_put_hdr_tso(struct fec_enet_priv_tx_q *txq, ebdp->cbd_esc = cpu_to_fec32(estatus); } - bdp->cbd_sc = cpu_to_fec16(status); - + bdp->cbd_sc = cpu_to_fec16(BD_ENET_TX_TC | BD_ENET_TX_READY | + ((bdp == txq->bd.last) ? BD_SC_WRAP : 0)); return 0; } @@ -1454,12 +1443,6 @@ static int fec_rxq(struct net_device *ndev, struct fec_enet_priv_rx_q *rxq, } rx_processing_done: - /* Clear the status flags for this buffer */ - status &= ~BD_ENET_RX_STATS; - - /* Mark the buffer empty */ - status |= BD_ENET_RX_EMPTY; - if (fep->bufdesc_ex) { struct bufdesc_ex *ebdp = (struct bufdesc_ex *)bdp; @@ -1471,7 +1454,8 @@ rx_processing_done: * performed before transferring ownership. */ wmb(); - bdp->cbd_sc = cpu_to_fec16(status); + bdp->cbd_sc = cpu_to_fec16(BD_ENET_RX_EMPTY | + ((bdp == rxq->bd.last) ? BD_SC_WRAP : 0)); /* Update BD pointer to next entry */ bdp = fec_enet_get_nextdesc(bdp, &rxq->bd); -- 2.5.0