Commit 4669bc90 authored by Dai Haruki's avatar Dai Haruki Committed by David S. Miller

gianfar: Add Scatter Gather support

Scatter Gather support in gianfar driver to handle fragmented frames on
the transmit side.
Signed-off-by: default avatarPoonam Aggrwal <poonam.aggrwal@freescale.com>
Signed-off-by: default avatarDai Haruki <dai.haruki@freescale.com>
Signed-off-by: default avatarAndy Fleming <afleming@freescale.com>
Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
parent 8882d9a6
......@@ -368,7 +368,7 @@ static int gfar_probe(struct of_device *ofdev,
if (priv->device_flags & FSL_GIANFAR_DEV_HAS_CSUM) {
priv->rx_csum_enable = 1;
dev->features |= NETIF_F_IP_CSUM;
dev->features |= NETIF_F_IP_CSUM | NETIF_F_SG | NETIF_F_HIGHDMA;
} else
priv->rx_csum_enable = 0;
......@@ -426,6 +426,7 @@ static int gfar_probe(struct of_device *ofdev,
priv->rx_buffer_size = DEFAULT_RX_BUFFER_SIZE;
priv->tx_ring_size = DEFAULT_TX_RING_SIZE;
priv->rx_ring_size = DEFAULT_RX_RING_SIZE;
priv->num_txbdfree = DEFAULT_TX_RING_SIZE;
priv->txcoalescing = DEFAULT_TX_COALESCE;
priv->txic = DEFAULT_TXIC;
......@@ -819,22 +820,26 @@ static void free_skb_resources(struct gfar_private *priv)
{
struct rxbd8 *rxbdp;
struct txbd8 *txbdp;
int i;
int i, j;
/* Go through all the buffer descriptors and free their data buffers */
txbdp = priv->tx_bd_base;
for (i = 0; i < priv->tx_ring_size; i++) {
if (!priv->tx_skbuff[i])
continue;
if (priv->tx_skbuff[i]) {
dma_unmap_single(&priv->dev->dev, txbdp->bufPtr,
txbdp->length,
DMA_TO_DEVICE);
dev_kfree_skb_any(priv->tx_skbuff[i]);
priv->tx_skbuff[i] = NULL;
dma_unmap_single(&priv->dev->dev, txbdp->bufPtr,
txbdp->length, DMA_TO_DEVICE);
txbdp->lstatus = 0;
for (j = 0; j < skb_shinfo(priv->tx_skbuff[i])->nr_frags; j++) {
txbdp++;
dma_unmap_page(&priv->dev->dev, txbdp->bufPtr,
txbdp->length, DMA_TO_DEVICE);
}
txbdp++;
dev_kfree_skb_any(priv->tx_skbuff[i]);
priv->tx_skbuff[i] = NULL;
}
kfree(priv->tx_skbuff);
......@@ -967,6 +972,7 @@ int startup_gfar(struct net_device *dev)
priv->rx_skbuff[i] = NULL;
/* Initialize some variables in our dev structure */
priv->num_txbdfree = priv->tx_ring_size;
priv->dirty_tx = priv->cur_tx = priv->tx_bd_base;
priv->cur_rx = priv->rx_bd_base;
priv->skb_curtx = priv->skb_dirtytx = 0;
......@@ -1207,28 +1213,84 @@ void inline gfar_tx_vlan(struct sk_buff *skb, struct txfcb *fcb)
fcb->vlctl = vlan_tx_tag_get(skb);
}
static inline struct txbd8 *skip_txbd(struct txbd8 *bdp, int stride,
struct txbd8 *base, int ring_size)
{
struct txbd8 *new_bd = bdp + stride;
return (new_bd >= (base + ring_size)) ? (new_bd - ring_size) : new_bd;
}
static inline struct txbd8 *next_txbd(struct txbd8 *bdp, struct txbd8 *base,
int ring_size)
{
return skip_txbd(bdp, 1, base, ring_size);
}
/* This is called by the kernel when a frame is ready for transmission. */
/* It is pointed to by the dev->hard_start_xmit function pointer */
static int gfar_start_xmit(struct sk_buff *skb, struct net_device *dev)
{
struct gfar_private *priv = netdev_priv(dev);
struct txfcb *fcb = NULL;
struct txbd8 *txbdp, *base;
struct txbd8 *txbdp, *txbdp_start, *base;
u32 lstatus;
int i;
u32 bufaddr;
unsigned long flags;
unsigned int nr_frags, length;
base = priv->tx_bd_base;
/* total number of fragments in the SKB */
nr_frags = skb_shinfo(skb)->nr_frags;
spin_lock_irqsave(&priv->txlock, flags);
/* check if there is space to queue this packet */
if (nr_frags > priv->num_txbdfree) {
/* no space, stop the queue */
netif_stop_queue(dev);
dev->stats.tx_fifo_errors++;
spin_unlock_irqrestore(&priv->txlock, flags);
return NETDEV_TX_BUSY;
}
/* Update transmit stats */
dev->stats.tx_bytes += skb->len;
/* Lock priv now */
spin_lock_irqsave(&priv->txlock, flags);
txbdp = txbdp_start = priv->cur_tx;
/* Point at the first free tx descriptor */
txbdp = priv->cur_tx;
base = priv->tx_bd_base;
if (nr_frags == 0) {
lstatus = txbdp->lstatus | BD_LFLAG(TXBD_LAST | TXBD_INTERRUPT);
} else {
/* Place the fragment addresses and lengths into the TxBDs */
for (i = 0; i < nr_frags; i++) {
/* Point at the next BD, wrapping as needed */
txbdp = next_txbd(txbdp, base, priv->tx_ring_size);
length = skb_shinfo(skb)->frags[i].size;
lstatus = txbdp->lstatus | length |
BD_LFLAG(TXBD_READY);
/* Handle the last BD specially */
if (i == nr_frags - 1)
lstatus |= BD_LFLAG(TXBD_LAST | TXBD_INTERRUPT);
bufaddr = dma_map_page(&dev->dev,
skb_shinfo(skb)->frags[i].page,
skb_shinfo(skb)->frags[i].page_offset,
length,
DMA_TO_DEVICE);
/* set the TxBD length and buffer pointer */
txbdp->bufPtr = bufaddr;
txbdp->lstatus = lstatus;
}
/* Clear all but the WRAP status flags */
lstatus = txbdp->lstatus & BD_LFLAG(TXBD_WRAP);
lstatus = txbdp_start->lstatus;
}
/* Set up checksumming */
if (CHECKSUM_PARTIAL == skb->ip_summed) {
......@@ -1246,48 +1308,45 @@ static int gfar_start_xmit(struct sk_buff *skb, struct net_device *dev)
gfar_tx_vlan(skb, fcb);
}
/* Set buffer length and pointer */
txbdp->bufPtr = dma_map_single(&dev->dev, skb->data,
skb->len, DMA_TO_DEVICE);
/* Save the skb pointer so we can free it later */
/* setup the TxBD length and buffer pointer for the first BD */
priv->tx_skbuff[priv->skb_curtx] = skb;
txbdp_start->bufPtr = dma_map_single(&dev->dev, skb->data,
skb_headlen(skb), DMA_TO_DEVICE);
/* Update the current skb pointer (wrapping if this was the last) */
priv->skb_curtx =
(priv->skb_curtx + 1) & TX_RING_MOD_MASK(priv->tx_ring_size);
/* Flag the BD as ready, interrupt-causing, last, and in need of CRC */
lstatus |=
BD_LFLAG(TXBD_READY | TXBD_LAST | TXBD_CRC | TXBD_INTERRUPT) |
skb->len;
dev->trans_start = jiffies;
lstatus |= BD_LFLAG(TXBD_CRC | TXBD_READY) | skb_headlen(skb);
/* The powerpc-specific eieio() is used, as wmb() has too strong
/*
* The powerpc-specific eieio() is used, as wmb() has too strong
* semantics (it requires synchronization between cacheable and
* uncacheable mappings, which eieio doesn't provide and which we
* don't need), thus requiring a more expensive sync instruction. At
* some point, the set of architecture-independent barrier functions
* should be expanded to include weaker barriers.
*/
eieio();
txbdp->lstatus = lstatus;
txbdp = next_bd(txbdp, base, priv->tx_ring_size);
txbdp_start->lstatus = lstatus;
/* Update the current skb pointer to the next entry we will use
* (wrapping if necessary) */
priv->skb_curtx = (priv->skb_curtx + 1) &
TX_RING_MOD_MASK(priv->tx_ring_size);
priv->cur_tx = next_txbd(txbdp, base, priv->tx_ring_size);
/* reduce TxBD free count */
priv->num_txbdfree -= (nr_frags + 1);
dev->trans_start = jiffies;
/* If the next BD still needs to be cleaned up, then the bds
are full. We need to tell the kernel to stop sending us stuff. */
if (txbdp == priv->dirty_tx) {
if (!priv->num_txbdfree) {
netif_stop_queue(dev);
dev->stats.tx_fifo_errors++;
}
/* Update the current txbd to the next one */
priv->cur_tx = txbdp;
/* Tell the DMA to go go go */
gfar_write(&priv->regs->tstat, TSTAT_CLEAR_THALT);
......@@ -1461,50 +1520,66 @@ static void gfar_timeout(struct net_device *dev)
/* Interrupt Handler for Transmit complete */
static int gfar_clean_tx_ring(struct net_device *dev)
{
struct txbd8 *bdp, *base;
struct gfar_private *priv = netdev_priv(dev);
struct txbd8 *bdp;
struct txbd8 *lbdp = NULL;
struct txbd8 *base = priv->tx_bd_base;
struct sk_buff *skb;
int skb_dirtytx;
int tx_ring_size = priv->tx_ring_size;
int frags = 0;
int i;
int howmany = 0;
u32 lstatus;
bdp = priv->dirty_tx;
base = priv->tx_bd_base;
while ((bdp->status & TXBD_READY) == 0) {
/* If dirty_tx and cur_tx are the same, then either the */
/* ring is empty or full now (it could only be full in the beginning, */
/* obviously). If it is empty, we are done. */
if ((bdp == priv->cur_tx) && (netif_queue_stopped(dev) == 0))
break;
skb_dirtytx = priv->skb_dirtytx;
howmany++;
while ((skb = priv->tx_skbuff[skb_dirtytx])) {
frags = skb_shinfo(skb)->nr_frags;
lbdp = skip_txbd(bdp, frags, base, tx_ring_size);
/* Deferred means some collisions occurred during transmit, */
/* but we eventually sent the packet. */
if (bdp->status & TXBD_DEF)
dev->stats.collisions++;
lstatus = lbdp->lstatus;
/* Unmap the DMA memory */
dma_unmap_single(&priv->dev->dev, bdp->bufPtr,
bdp->length, DMA_TO_DEVICE);
/* Only clean completed frames */
if ((lstatus & BD_LFLAG(TXBD_READY)) &&
(lstatus & BD_LENGTH_MASK))
break;
dma_unmap_single(&dev->dev,
bdp->bufPtr,
bdp->length,
DMA_TO_DEVICE);
/* Free the sk buffer associated with this TxBD */
dev_kfree_skb_irq(priv->tx_skbuff[priv->skb_dirtytx]);
bdp->lstatus &= BD_LFLAG(TXBD_WRAP);
bdp = next_txbd(bdp, base, tx_ring_size);
priv->tx_skbuff[priv->skb_dirtytx] = NULL;
priv->skb_dirtytx =
(priv->skb_dirtytx +
1) & TX_RING_MOD_MASK(priv->tx_ring_size);
for (i = 0; i < frags; i++) {
dma_unmap_page(&dev->dev,
bdp->bufPtr,
bdp->length,
DMA_TO_DEVICE);
bdp->lstatus &= BD_LFLAG(TXBD_WRAP);
bdp = next_txbd(bdp, base, tx_ring_size);
}
/* Clean BD length for empty detection */
bdp->length = 0;
dev_kfree_skb_any(skb);
priv->tx_skbuff[skb_dirtytx] = NULL;
bdp = next_bd(bdp, base, priv->tx_ring_size);
skb_dirtytx = (skb_dirtytx + 1) &
TX_RING_MOD_MASK(tx_ring_size);
howmany++;
priv->num_txbdfree += frags + 1;
}
/* Move dirty_tx to be the next bd */
priv->dirty_tx = bdp;
/* If we freed a buffer, we can restart transmission, if necessary */
if (netif_queue_stopped(dev) && priv->num_txbdfree)
netif_wake_queue(dev);
/* We freed a buffer, so now we can restart transmission */
if (netif_queue_stopped(dev))
netif_wake_queue(dev);
} /* while ((bdp->status & TXBD_READY) == 0) */
/* Update dirty indicators */
priv->skb_dirtytx = skb_dirtytx;
priv->dirty_tx = bdp;
dev->stats.tx_packets += howmany;
......
......@@ -728,6 +728,7 @@ struct gfar_private {
struct txbd8 *dirty_tx; /* First buffer in line
to be transmitted */
unsigned int tx_ring_size;
unsigned int num_txbdfree; /* number of TxBDs free */
/* RX Locked fields */
spinlock_t rxlock;
......
......@@ -475,6 +475,7 @@ static int gfar_sringparam(struct net_device *dev, struct ethtool_ringparam *rva
/* Change the size */
priv->rx_ring_size = rvals->rx_pending;
priv->tx_ring_size = rvals->tx_pending;
priv->num_txbdfree = priv->tx_ring_size;
/* Rebuild the rings with the new size */
if (dev->flags & IFF_UP) {
......@@ -623,6 +624,7 @@ const struct ethtool_ops gfar_ethtool_ops = {
.get_tx_csum = gfar_get_tx_csum,
.set_rx_csum = gfar_set_rx_csum,
.set_tx_csum = gfar_set_tx_csum,
.set_sg = ethtool_op_set_sg,
.get_msglevel = gfar_get_msglevel,
.set_msglevel = gfar_set_msglevel,
#ifdef CONFIG_PM
......
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