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Commit 1fa38c58 authored by Lennert Buytenhek's avatar Lennert Buytenhek Committed by Lennert Buytenhek
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mv643xx_eth: move all work to the napi poll handler 

Move link status handling, transmit reclaim and TX_END handling from
the interrupt handler to the napi poll handler.  This allows switching
->lock over to a non-IRQ-safe lock and removes all explicit interrupt
disabling from the driver.
Signed-off-by: default avatarLennert Buytenhek <buytenh@marvell.com>
parent e5ef1de1
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Showing with 275 additions and 246 deletions
drivers/net/mv643xx_eth.c
View file @ 1fa38c58
......@@ -57,7 +57,6 @@
static char mv643xx_eth_driver_name[] = "mv643xx_eth";
static char mv643xx_eth_driver_version[] = "1.3";
#define MV643XX_ETH_TX_FAST_REFILL
/*
* Registers shared between all ports.
......@@ -103,7 +102,6 @@ static char mv643xx_eth_driver_version[] = "1.3";
#define TX_BW_MTU(p) (0x0458 + ((p) << 10))
#define TX_BW_BURST(p) (0x045c + ((p) << 10))
#define INT_CAUSE(p) (0x0460 + ((p) << 10))
#define INT_TX_END_0 0x00080000
#define INT_TX_END 0x07f80000
#define INT_RX 0x000003fc
#define INT_EXT 0x00000002
......@@ -355,6 +353,14 @@ struct mv643xx_eth_private {
struct work_struct tx_timeout_task;
struct mii_if_info mii;
struct napi_struct napi;
u8 work_link;
u8 work_tx;
u8 work_tx_end;
u8 work_rx;
u8 work_rx_refill;
u8 work_rx_oom;
/*
* RX state.
*/
......@@ -362,7 +368,6 @@ struct mv643xx_eth_private {
unsigned long rx_desc_sram_addr;
int rx_desc_sram_size;
int rxq_count;
struct napi_struct napi;
struct timer_list rx_oom;
struct rx_queue rxq[8];
......@@ -374,9 +379,6 @@ struct mv643xx_eth_private {
int tx_desc_sram_size;
int txq_count;
struct tx_queue txq[8];
#ifdef MV643XX_ETH_TX_FAST_REFILL
int tx_clean_threshold;
#endif
};
......@@ -446,82 +448,19 @@ static void txq_disable(struct tx_queue *txq)
udelay(10);
}
static void __txq_maybe_wake(struct tx_queue *txq)
static void txq_maybe_wake(struct tx_queue *txq)
{
struct mv643xx_eth_private *mp = txq_to_mp(txq);
struct netdev_queue *nq = netdev_get_tx_queue(mp->dev, txq->index);
spin_lock(&mp->lock);
if (txq->tx_ring_size - txq->tx_desc_count >= MAX_SKB_FRAGS + 1)
netif_tx_wake_queue(nq);
spin_unlock(&mp->lock);
}
/* rx ***********************************************************************/
static void txq_reclaim(struct tx_queue *txq, int force);
static int rxq_refill(struct rx_queue *rxq, int budget, int *oom)
{
int skb_size;
int refilled;
/*
* Reserve 2+14 bytes for an ethernet header (the hardware
* automatically prepends 2 bytes of dummy data to each
* received packet), 16 bytes for up to four VLAN tags, and
* 4 bytes for the trailing FCS -- 36 bytes total.
*/
skb_size = rxq_to_mp(rxq)->dev->mtu + 36;
/*
* Make sure that the skb size is a multiple of 8 bytes, as
* the lower three bits of the receive descriptor's buffer
* size field are ignored by the hardware.
*/
skb_size = (skb_size + 7) & ~7;
refilled = 0;
while (refilled < budget && rxq->rx_desc_count < rxq->rx_ring_size) {
struct sk_buff *skb;
int unaligned;
int rx;
skb = dev_alloc_skb(skb_size + dma_get_cache_alignment() - 1);
if (skb == NULL) {
*oom = 1;
break;
}
unaligned = (u32)skb->data & (dma_get_cache_alignment() - 1);
if (unaligned)
skb_reserve(skb, dma_get_cache_alignment() - unaligned);
refilled++;
rxq->rx_desc_count++;
rx = rxq->rx_used_desc++;
if (rxq->rx_used_desc == rxq->rx_ring_size)
rxq->rx_used_desc = 0;
rxq->rx_desc_area[rx].buf_ptr = dma_map_single(NULL, skb->data,
skb_size, DMA_FROM_DEVICE);
rxq->rx_desc_area[rx].buf_size = skb_size;
rxq->rx_skb[rx] = skb;
wmb();
rxq->rx_desc_area[rx].cmd_sts = BUFFER_OWNED_BY_DMA |
RX_ENABLE_INTERRUPT;
wmb();
/*
* The hardware automatically prepends 2 bytes of
* dummy data to each received packet, so that the
* IP header ends up 16-byte aligned.
*/
skb_reserve(skb, 2);
}
return refilled;
}
/* rx napi ******************************************************************/
static int rxq_process(struct rx_queue *rxq, int budget)
{
struct mv643xx_eth_private *mp = rxq_to_mp(rxq);
......@@ -553,6 +492,8 @@ static int rxq_process(struct rx_queue *rxq, int budget)
rxq->rx_desc_count--;
rx++;
mp->work_rx_refill |= 1 << rxq->index;
/*
* Update statistics.
*
......@@ -605,54 +546,78 @@ static int rxq_process(struct rx_queue *rxq, int budget)
mp->dev->last_rx = jiffies;
}
if (rx < budget)
mp->work_rx &= ~(1 << rxq->index);
return rx;
}
static int mv643xx_eth_poll(struct napi_struct *napi, int budget)
static int rxq_refill(struct rx_queue *rxq, int budget)
{
struct mv643xx_eth_private *mp;
int work_done;
int oom;
int i;
struct mv643xx_eth_private *mp = rxq_to_mp(rxq);
int skb_size;
int refilled;
mp = container_of(napi, struct mv643xx_eth_private, napi);
/*
* Reserve 2+14 bytes for an ethernet header (the hardware
* automatically prepends 2 bytes of dummy data to each
* received packet), 16 bytes for up to four VLAN tags, and
* 4 bytes for the trailing FCS -- 36 bytes total.
*/
skb_size = rxq_to_mp(rxq)->dev->mtu + 36;
#ifdef MV643XX_ETH_TX_FAST_REFILL
if (++mp->tx_clean_threshold > 5) {
mp->tx_clean_threshold = 0;
for (i = 0; i < mp->txq_count; i++)
txq_reclaim(mp->txq + i, 0);
/*
* Make sure that the skb size is a multiple of 8 bytes, as
* the lower three bits of the receive descriptor's buffer
* size field are ignored by the hardware.
*/
skb_size = (skb_size + 7) & ~7;
spin_lock_irq(&mp->lock);
__txq_maybe_wake(mp->txq);
spin_unlock_irq(&mp->lock);
refilled = 0;
while (refilled < budget && rxq->rx_desc_count < rxq->rx_ring_size) {
struct sk_buff *skb;
int unaligned;
int rx;
skb = dev_alloc_skb(skb_size + dma_get_cache_alignment() - 1);
if (skb == NULL) {
mp->work_rx_oom |= 1 << rxq->index;
goto oom;
}
#endif
work_done = 0;
oom = 0;
for (i = mp->rxq_count - 1; work_done < budget && i >= 0; i--) {
struct rx_queue *rxq = mp->rxq + i;
unaligned = (u32)skb->data & (dma_get_cache_alignment() - 1);
if (unaligned)
skb_reserve(skb, dma_get_cache_alignment() - unaligned);
work_done += rxq_process(rxq, budget - work_done);
work_done += rxq_refill(rxq, budget - work_done, &oom);
}
refilled++;
rxq->rx_desc_count++;
if (work_done < budget) {
if (oom)
mod_timer(&mp->rx_oom, jiffies + (HZ / 10));
netif_rx_complete(mp->dev, napi);
wrl(mp, INT_MASK(mp->port_num), INT_TX_END | INT_RX | INT_EXT);
}
rx = rxq->rx_used_desc++;
if (rxq->rx_used_desc == rxq->rx_ring_size)
rxq->rx_used_desc = 0;
return work_done;
}
rxq->rx_desc_area[rx].buf_ptr = dma_map_single(NULL, skb->data,
skb_size, DMA_FROM_DEVICE);
rxq->rx_desc_area[rx].buf_size = skb_size;
rxq->rx_skb[rx] = skb;
wmb();
rxq->rx_desc_area[rx].cmd_sts = BUFFER_OWNED_BY_DMA |
RX_ENABLE_INTERRUPT;
wmb();
static inline void oom_timer_wrapper(unsigned long data)
{
struct mv643xx_eth_private *mp = (void *)data;
/*
* The hardware automatically prepends 2 bytes of
* dummy data to each received packet, so that the
* IP header ends up 16-byte aligned.
*/
skb_reserve(skb, 2);
}
napi_schedule(&mp->napi);
if (refilled < budget)
mp->work_rx_refill &= ~(1 << rxq->index);
oom:
return refilled;
}
......@@ -807,9 +772,8 @@ static void txq_submit_skb(struct tx_queue *txq, struct sk_buff *skb)
wmb();
desc->cmd_sts = cmd_sts;
/* clear TX_END interrupt status */
wrl(mp, INT_CAUSE(mp->port_num), ~(INT_TX_END_0 << txq->index));
rdl(mp, INT_CAUSE(mp->port_num));
/* clear TX_END status */
mp->work_tx_end &= ~(1 << txq->index);
/* ensure all descriptors are written before poking hardware */
wmb();
......@@ -825,7 +789,6 @@ static int mv643xx_eth_xmit(struct sk_buff *skb, struct net_device *dev)
int queue;
struct tx_queue *txq;
struct netdev_queue *nq;
unsigned long flags;
int entries_left;
if (has_tiny_unaligned_frags(skb) && __skb_linearize(skb)) {
......@@ -840,10 +803,10 @@ static int mv643xx_eth_xmit(struct sk_buff *skb, struct net_device *dev)
txq = mp->txq + queue;
nq = netdev_get_tx_queue(dev, queue);
spin_lock_irqsave(&mp->lock, flags);
spin_lock(&mp->lock);
if (txq->tx_ring_size - txq->tx_desc_count < MAX_SKB_FRAGS + 1) {
spin_unlock_irqrestore(&mp->lock, flags);
spin_unlock(&mp->lock);
if (net_ratelimit())
dev_printk(KERN_ERR, &dev->dev, "tx queue full?!\n");
kfree_skb(skb);
......@@ -859,12 +822,105 @@ static int mv643xx_eth_xmit(struct sk_buff *skb, struct net_device *dev)
if (entries_left < MAX_SKB_FRAGS + 1)
netif_tx_stop_queue(nq);
spin_unlock_irqrestore(&mp->lock, flags);
spin_unlock(&mp->lock);
return NETDEV_TX_OK;
}
/* tx napi ******************************************************************/
static void txq_kick(struct tx_queue *txq)
{
struct mv643xx_eth_private *mp = txq_to_mp(txq);
u32 hw_desc_ptr;
u32 expected_ptr;
spin_lock(&mp->lock);
if (rdl(mp, TXQ_COMMAND(mp->port_num)) & (1 << txq->index))
goto out;
hw_desc_ptr = rdl(mp, TXQ_CURRENT_DESC_PTR(mp->port_num, txq->index));
expected_ptr = (u32)txq->tx_desc_dma +
txq->tx_curr_desc * sizeof(struct tx_desc);
if (hw_desc_ptr != expected_ptr)
txq_enable(txq);
out:
spin_unlock(&mp->lock);
mp->work_tx_end &= ~(1 << txq->index);
}
static int txq_reclaim(struct tx_queue *txq, int budget, int force)
{
struct mv643xx_eth_private *mp = txq_to_mp(txq);
int reclaimed;
spin_lock(&mp->lock);
reclaimed = 0;
while (reclaimed < budget && txq->tx_desc_count > 0) {
int tx_index;
struct tx_desc *desc;
u32 cmd_sts;
struct sk_buff *skb;
dma_addr_t addr;
int count;
tx_index = txq->tx_used_desc;
desc = &txq->tx_desc_area[tx_index];
cmd_sts = desc->cmd_sts;
if (cmd_sts & BUFFER_OWNED_BY_DMA) {
if (!force)
break;
desc->cmd_sts = cmd_sts & ~BUFFER_OWNED_BY_DMA;
}
txq->tx_used_desc = tx_index + 1;
if (txq->tx_used_desc == txq->tx_ring_size)
txq->tx_used_desc = 0;
reclaimed++;
txq->tx_desc_count--;
addr = desc->buf_ptr;
count = desc->byte_cnt;
skb = txq->tx_skb[tx_index];
txq->tx_skb[tx_index] = NULL;
if (cmd_sts & ERROR_SUMMARY) {
dev_printk(KERN_INFO, &mp->dev->dev, "tx error\n");
mp->dev->stats.tx_errors++;
}
/*
* Drop mp->lock while we free the skb.
*/
spin_unlock(&mp->lock);
if (cmd_sts & TX_FIRST_DESC)
dma_unmap_single(NULL, addr, count, DMA_TO_DEVICE);
else
dma_unmap_page(NULL, addr, count, DMA_TO_DEVICE);
if (skb)
dev_kfree_skb(skb);
spin_lock(&mp->lock);
}
if (reclaimed < budget)
mp->work_tx &= ~(1 << txq->index);
spin_unlock(&mp->lock);
return reclaimed;
}
/* tx rate control **********************************************************/
/*
* Set total maximum TX rate (shared by all TX queues for this port)
......@@ -1648,7 +1704,6 @@ static int txq_init(struct mv643xx_eth_private *mp, int index)
return 0;
out_free:
if (index == 0 && size <= mp->tx_desc_sram_size)
iounmap(txq->tx_desc_area);
......@@ -1661,84 +1716,74 @@ out:
return -ENOMEM;
}
static void txq_reclaim(struct tx_queue *txq, int force)
static void txq_deinit(struct tx_queue *txq)
{
struct mv643xx_eth_private *mp = txq_to_mp(txq);
unsigned long flags;
spin_lock_irqsave(&mp->lock, flags);
while (txq->tx_desc_count > 0) {
int tx_index;
struct tx_desc *desc;
u32 cmd_sts;
struct sk_buff *skb;
dma_addr_t addr;
int count;
txq_disable(txq);
txq_reclaim(txq, txq->tx_ring_size, 1);
tx_index = txq->tx_used_desc;
desc = &txq->tx_desc_area[tx_index];
cmd_sts = desc->cmd_sts;
BUG_ON(txq->tx_used_desc != txq->tx_curr_desc);
if (cmd_sts & BUFFER_OWNED_BY_DMA) {
if (!force)
break;
desc->cmd_sts = cmd_sts & ~BUFFER_OWNED_BY_DMA;
}
if (txq->index == 0 &&
txq->tx_desc_area_size <= mp->tx_desc_sram_size)
iounmap(txq->tx_desc_area);
else
dma_free_coherent(NULL, txq->tx_desc_area_size,
txq->tx_desc_area, txq->tx_desc_dma);
txq->tx_used_desc = tx_index + 1;
if (txq->tx_used_desc == txq->tx_ring_size)
txq->tx_used_desc = 0;
txq->tx_desc_count--;
kfree(txq->tx_skb);
}
addr = desc->buf_ptr;
count = desc->byte_cnt;
skb = txq->tx_skb[tx_index];
txq->tx_skb[tx_index] = NULL;
if (cmd_sts & ERROR_SUMMARY) {
dev_printk(KERN_INFO, &mp->dev->dev, "tx error\n");
mp->dev->stats.tx_errors++;
}
/* netdev ops and related ***************************************************/
static int mv643xx_eth_collect_events(struct mv643xx_eth_private *mp)
{
u32 int_cause;
u32 int_cause_ext;
/*
* Drop mp->lock while we free the skb.
*/
spin_unlock_irqrestore(&mp->lock, flags);
int_cause = rdl(mp, INT_CAUSE(mp->port_num)) &
(INT_TX_END | INT_RX | INT_EXT);
if (int_cause == 0)
return 0;
if (cmd_sts & TX_FIRST_DESC)
dma_unmap_single(NULL, addr, count, DMA_TO_DEVICE);
else
dma_unmap_page(NULL, addr, count, DMA_TO_DEVICE);
int_cause_ext = 0;
if (int_cause & INT_EXT)
int_cause_ext = rdl(mp, INT_CAUSE_EXT(mp->port_num));
if (skb)
dev_kfree_skb_irq(skb);
int_cause &= INT_TX_END | INT_RX;
if (int_cause) {
wrl(mp, INT_CAUSE(mp->port_num), ~int_cause);
mp->work_tx_end |= ((int_cause & INT_TX_END) >> 19) &
~(rdl(mp, TXQ_COMMAND(mp->port_num)) & 0xff);
mp->work_rx |= (int_cause & INT_RX) >> 2;
}
spin_lock_irqsave(&mp->lock, flags);
int_cause_ext &= INT_EXT_LINK_PHY | INT_EXT_TX;
if (int_cause_ext) {
wrl(mp, INT_CAUSE_EXT(mp->port_num), ~int_cause_ext);
if (int_cause_ext & INT_EXT_LINK_PHY)
mp->work_link = 1;
mp->work_tx |= int_cause_ext & INT_EXT_TX;
}
spin_unlock_irqrestore(&mp->lock, flags);
return 1;
}
static void txq_deinit(struct tx_queue *txq)
static irqreturn_t mv643xx_eth_irq(int irq, void *dev_id)
{
struct mv643xx_eth_private *mp = txq_to_mp(txq);
txq_disable(txq);
txq_reclaim(txq, 1);
struct net_device *dev = (struct net_device *)dev_id;
struct mv643xx_eth_private *mp = netdev_priv(dev);
BUG_ON(txq->tx_used_desc != txq->tx_curr_desc);
if (unlikely(!mv643xx_eth_collect_events(mp)))
return IRQ_NONE;
if (txq->index == 0 &&
txq->tx_desc_area_size <= mp->tx_desc_sram_size)
iounmap(txq->tx_desc_area);
else
dma_free_coherent(NULL, txq->tx_desc_area_size,
txq->tx_desc_area, txq->tx_desc_dma);
wrl(mp, INT_MASK(mp->port_num), 0);
napi_schedule(&mp->napi);
kfree(txq->tx_skb);
return IRQ_HANDLED;
}
/* netdev ops and related ***************************************************/
static void handle_link_event(struct mv643xx_eth_private *mp)
{
struct net_device *dev = mp->dev;
......@@ -1759,7 +1804,7 @@ static void handle_link_event(struct mv643xx_eth_private *mp)
for (i = 0; i < mp->txq_count; i++) {
struct tx_queue *txq = mp->txq + i;
txq_reclaim(txq, 1);
txq_reclaim(txq, txq->tx_ring_size, 1);
txq_reset_hw_ptr(txq);
}
}
......@@ -1792,86 +1837,72 @@ static void handle_link_event(struct mv643xx_eth_private *mp)
netif_carrier_on(dev);
}
static irqreturn_t mv643xx_eth_irq(int irq, void *dev_id)
static int mv643xx_eth_poll(struct napi_struct *napi, int budget)
{
struct net_device *dev = (struct net_device *)dev_id;
struct mv643xx_eth_private *mp = netdev_priv(dev);
u32 int_cause;
u32 int_cause_ext;
int_cause = rdl(mp, INT_CAUSE(mp->port_num)) &
(INT_TX_END | INT_RX | INT_EXT);
if (int_cause == 0)
return IRQ_NONE;
struct mv643xx_eth_private *mp;
int work_done;
int_cause_ext = 0;
if (int_cause & INT_EXT) {
int_cause_ext = rdl(mp, INT_CAUSE_EXT(mp->port_num))
& (INT_EXT_LINK_PHY | INT_EXT_TX);
wrl(mp, INT_CAUSE_EXT(mp->port_num), ~int_cause_ext);
}
mp = container_of(napi, struct mv643xx_eth_private, napi);
if (int_cause_ext & INT_EXT_LINK_PHY)
handle_link_event(mp);
mp->work_rx_refill |= mp->work_rx_oom;
mp->work_rx_oom = 0;
/*
* RxBuffer or RxError set for any of the 8 queues?
*/
if (int_cause & INT_RX) {
wrl(mp, INT_CAUSE(mp->port_num), ~(int_cause & INT_RX));
wrl(mp, INT_MASK(mp->port_num), 0x00000000);
rdl(mp, INT_MASK(mp->port_num));
work_done = 0;
while (work_done < budget) {
u8 queue_mask;
int queue;
int work_tbd;
napi_schedule(&mp->napi);
if (mp->work_link) {
mp->work_link = 0;
handle_link_event(mp);
continue;
}
/*
* TxBuffer or TxError set for any of the 8 queues?
*/
if (int_cause_ext & INT_EXT_TX) {
int i;
for (i = 0; i < mp->txq_count; i++)
txq_reclaim(mp->txq + i, 0);
/*
* Enough space again in the primary TX queue for a
* full packet?
*/
spin_lock(&mp->lock);
__txq_maybe_wake(mp->txq);
spin_unlock(&mp->lock);
queue_mask = mp->work_tx | mp->work_tx_end |
mp->work_rx | mp->work_rx_refill;
if (!queue_mask) {
if (mv643xx_eth_collect_events(mp))
continue;
break;
}
/*
* Any TxEnd interrupts?
*/
if (int_cause & INT_TX_END) {
int i;
queue = fls(queue_mask) - 1;
queue_mask = 1 << queue;
wrl(mp, INT_CAUSE(mp->port_num), ~(int_cause & INT_TX_END));
work_tbd = budget - work_done;
if (work_tbd > 16)
work_tbd = 16;
spin_lock(&mp->lock);
for (i = 0; i < 8; i++) {
struct tx_queue *txq = mp->txq + i;
u32 hw_desc_ptr;
u32 expected_ptr;
if (mp->work_tx_end & queue_mask) {
txq_kick(mp->txq + queue);
} else if (mp->work_tx & queue_mask) {
work_done += txq_reclaim(mp->txq + queue, work_tbd, 0);
txq_maybe_wake(mp->txq + queue);
} else if (mp->work_rx & queue_mask) {
work_done += rxq_process(mp->rxq + queue, work_tbd);
} else if (mp->work_rx_refill & queue_mask) {
work_done += rxq_refill(mp->rxq + queue, work_tbd);
} else {
BUG();
}
}
if ((int_cause & (INT_TX_END_0 << i)) == 0)
continue;
if (work_done < budget) {
if (mp->work_rx_oom)
mod_timer(&mp->rx_oom, jiffies + (HZ / 10));
napi_complete(napi);
wrl(mp, INT_MASK(mp->port_num), INT_TX_END | INT_RX | INT_EXT);
}
hw_desc_ptr =
rdl(mp, TXQ_CURRENT_DESC_PTR(mp->port_num, i));
expected_ptr = (u32)txq->tx_desc_dma +
txq->tx_curr_desc * sizeof(struct tx_desc);
return work_done;
}
if (hw_desc_ptr != expected_ptr)
txq_enable(txq);
}
spin_unlock(&mp->lock);
}
static inline void oom_timer_wrapper(unsigned long data)
{
struct mv643xx_eth_private *mp = (void *)data;
return IRQ_HANDLED;
napi_schedule(&mp->napi);
}
static void phy_reset(struct mv643xx_eth_private *mp)
......@@ -2000,7 +2031,6 @@ static int mv643xx_eth_open(struct net_device *dev)
{
struct mv643xx_eth_private *mp = netdev_priv(dev);
int err;
int oom;
int i;
wrl(mp, INT_CAUSE(mp->port_num), 0);
......@@ -2018,7 +2048,6 @@ static int mv643xx_eth_open(struct net_device *dev)
napi_enable(&mp->napi);
oom = 0;
for (i = 0; i < mp->rxq_count; i++) {
err = rxq_init(mp, i);
if (err) {
......@@ -2027,10 +2056,10 @@ static int mv643xx_eth_open(struct net_device *dev)
goto out;
}
rxq_refill(mp->rxq + i, INT_MAX, &oom);
rxq_refill(mp->rxq + i, INT_MAX);
}
if (oom) {
if (mp->work_rx_oom) {
mp->rx_oom.expires = jiffies + (HZ / 10);
add_timer(&mp->rx_oom);
}
......
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