[PATCH net-next V3 08/16] net: fec: set cbd_sc without relying on previous value
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: * performe
RE: [PATCH net-next V3 08/16] net: fec: set cbd_sc without relying on previous value
From: Troy Kisky Sent: Wednesday, April 06, 2016 10:26 AM > To: netdev@vger.kernel.org; da...@davemloft.net; Fugang Duan > ; lzn...@gmail.com > Cc: Fabio Estevam ; l.st...@pengutronix.de; > and...@lunn.ch; trem...@gmail.com; g...@uclinux.org; linux-arm- > ker...@lists.infradead.org; johan...@sipsolutions.net; > stillcompil...@gmail.com; sergei.shtyl...@cogentembedded.com; > a...@arndb.de; Troy Kisky > Subject: [PATCH net-next V3 08/16] net: fec: set cbd_sc without relying on > previous value > > 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); >