[PATCH] [3/4] pasemi_mac: cleanups and rx performance improvements
Olof Johansson
olof at lixom.net
Mon Apr 16 16:19:40 EST 2007
NAPI fixes and cleanups for pasemi_mac:
* Timer changes/fixes
* Abstract out the rx intr restart to a separate function
* Similar function for tx intr to reset to a known clear state even if
firmware used the same interface
* Add a copy-break and recycle the SKB in the driver for small
packets
* Other cleanups to rx path
Signed-off-by: Olof Johansson <olof at lixom.net>
Index: powerpc/drivers/net/pasemi_mac.c
===================================================================
--- powerpc.orig/drivers/net/pasemi_mac.c
+++ powerpc/drivers/net/pasemi_mac.c
@@ -59,12 +59,6 @@
#define BUF_SIZE 1646 /* 1500 MTU + ETH_HLEN + VLAN_HLEN + 2 64B cachelines */
-/* XXXOJN these should come out of the device tree some day */
-#define PAS_DMA_CAP_BASE 0xe00d0040
-#define PAS_DMA_CAP_SIZE 0x100
-#define PAS_DMA_COM_BASE 0xe00d0100
-#define PAS_DMA_COM_SIZE 0x100
-
static struct pasdma_status *dma_status;
static int pasemi_get_mac_addr(struct pasemi_mac *mac)
@@ -277,8 +271,8 @@ static void pasemi_mac_free_rx_resources
for (i = 0; i < RX_RING_SIZE; i++) {
info = &RX_DESC_INFO(mac, i);
dp = &RX_DESC(mac, i);
- if (info->dma) {
- if (info->skb) {
+ if (info->skb) {
+ if (info->dma) {
pci_unmap_single(mac->dma_pdev,
info->dma,
info->skb->len,
@@ -309,84 +303,122 @@ static void pasemi_mac_replenish_rx_ring
struct pasemi_mac *mac = netdev_priv(dev);
unsigned int i;
int start = mac->rx->next_to_fill;
- unsigned int count;
+ unsigned int limit, count;
- count = (mac->rx->next_to_clean + RX_RING_SIZE -
+ limit = (mac->rx->next_to_clean + RX_RING_SIZE -
mac->rx->next_to_fill) & (RX_RING_SIZE - 1);
/* Check to see if we're doing first-time setup */
if (unlikely(mac->rx->next_to_clean == 0 && mac->rx->next_to_fill == 0))
- count = RX_RING_SIZE;
+ limit = RX_RING_SIZE;
- if (count <= 0)
+ if (limit <= 0)
return;
- for (i = start; i < start + count; i++) {
+ i = start;
+
+ for (count = limit; count; count--) {
struct pasemi_mac_buffer *info = &RX_DESC_INFO(mac, i);
u64 *buff = &RX_BUFF(mac, i);
struct sk_buff *skb;
dma_addr_t dma;
- skb = dev_alloc_skb(BUF_SIZE);
+ /* skb might still be in there for recycle on short receives */
+ if (info->skb)
+ skb = info->skb;
+ else
+ skb = dev_alloc_skb(BUF_SIZE);
- if (!skb) {
- count = i - start;
+ if (unlikely(!skb))
break;
- }
skb->dev = dev;
dma = pci_map_single(mac->dma_pdev, skb->data, skb->len,
PCI_DMA_FROMDEVICE);
- if (dma_mapping_error(dma)) {
+ if (unlikely(dma_mapping_error(dma))) {
dev_kfree_skb_irq(info->skb);
- count = i - start;
break;
}
info->skb = skb;
info->dma = dma;
*buff = XCT_RXB_LEN(BUF_SIZE) | XCT_RXB_ADDR(dma);
+ i++;
}
wmb();
pci_write_config_dword(mac->dma_pdev,
PAS_DMA_RXCHAN_INCR(mac->dma_rxch),
- count);
+ limit - count);
pci_write_config_dword(mac->dma_pdev,
PAS_DMA_RXINT_INCR(mac->dma_if),
- count);
+ limit - count);
+
+ mac->rx->next_to_fill += limit - count;
+}
+
+static void pasemi_mac_restart_rx_intr(struct pasemi_mac *mac)
+{
+ unsigned int reg, stat;
+ /* Re-enable packet count interrupts: finally
+ * ack the packet count interrupt we got in rx_intr.
+ */
+
+ pci_read_config_dword(mac->iob_pdev,
+ PAS_IOB_DMA_RXCH_STAT(mac->dma_rxch),
+ &stat);
+
+ reg = PAS_IOB_DMA_RXCH_RESET_PCNT(stat & PAS_IOB_DMA_RXCH_STAT_CNTDEL_M) |
+ PAS_IOB_DMA_RXCH_RESET_PINTC;
+
+ pci_write_config_dword(mac->iob_pdev,
+ PAS_IOB_DMA_RXCH_RESET(mac->dma_rxch),
+ reg);
+}
+
+static void pasemi_mac_restart_tx_intr(struct pasemi_mac *mac)
+{
+ unsigned int reg, stat;
- mac->rx->next_to_fill += count;
+ /* Re-enable packet count interrupts */
+ pci_read_config_dword(mac->iob_pdev,
+ PAS_IOB_DMA_TXCH_STAT(mac->dma_txch), &stat);
+
+ reg = PAS_IOB_DMA_TXCH_RESET_PCNT(stat & PAS_IOB_DMA_TXCH_STAT_CNTDEL_M) |
+ PAS_IOB_DMA_TXCH_RESET_PINTC;
+
+ pci_write_config_dword(mac->iob_pdev,
+ PAS_IOB_DMA_TXCH_RESET(mac->dma_txch), reg);
}
+
static int pasemi_mac_clean_rx(struct pasemi_mac *mac, int limit)
{
- unsigned int i;
- int start, count;
+ unsigned int n;
+ int count;
+ struct pas_dma_xct_descr *dp;
+ struct pasemi_mac_buffer *info;
+ struct sk_buff *skb;
+ unsigned int i, len;
+ u64 macrx;
+ dma_addr_t dma;
spin_lock(&mac->rx->lock);
- start = mac->rx->next_to_clean;
- count = 0;
-
- for (i = start; i < (start + RX_RING_SIZE) && count < limit; i++) {
- struct pas_dma_xct_descr *dp;
- struct pasemi_mac_buffer *info;
- struct sk_buff *skb;
- unsigned int j, len;
- dma_addr_t dma;
+ n = mac->rx->next_to_clean;
+ for (count = limit; count; count--) {
rmb();
- dp = &RX_DESC(mac, i);
+ dp = &RX_DESC(mac, n);
- if (!(dp->macrx & XCT_MACRX_O))
- break;
+ macrx = dp->macrx;
- count++;
+ if (!(macrx & XCT_MACRX_O))
+ break;
info = NULL;
@@ -398,29 +430,42 @@ static int pasemi_mac_clean_rx(struct pa
*/
dma = (dp->ptr & XCT_PTR_ADDR_M);
- for (j = start; j < (start + RX_RING_SIZE); j++) {
- info = &RX_DESC_INFO(mac, j);
+ for (i = n; i < (n + RX_RING_SIZE); i++) {
+ info = &RX_DESC_INFO(mac, i);
if (info->dma == dma)
break;
}
- BUG_ON(!info);
- BUG_ON(info->dma != dma);
+ skb = info->skb;
+ info->dma = 0;
- pci_unmap_single(mac->dma_pdev, info->dma, info->skb->len,
+ pci_unmap_single(mac->dma_pdev, dma, skb->len,
PCI_DMA_FROMDEVICE);
- skb = info->skb;
+ len = (macrx & XCT_MACRX_LLEN_M) >> XCT_MACRX_LLEN_S;
- len = (dp->macrx & XCT_MACRX_LLEN_M) >> XCT_MACRX_LLEN_S;
+ if (len < 256) {
+ struct sk_buff *new_skb =
+ netdev_alloc_skb(mac->netdev, len + NET_IP_ALIGN);
+ if (new_skb) {
+ skb_reserve(new_skb, NET_IP_ALIGN);
+ memcpy(new_skb->data - NET_IP_ALIGN,
+ skb->data - NET_IP_ALIGN,
+ len + NET_IP_ALIGN);
+ /* save the skb in buffer_info as good */
+ skb = new_skb;
+ }
+ /* else just continue with the old one */
+ } else
+ info->skb = NULL;
skb_put(skb, len);
skb->protocol = eth_type_trans(skb, mac->netdev);
- if ((dp->macrx & XCT_MACRX_HTY_M) == XCT_MACRX_HTY_IPV4_OK) {
+ if ((macrx & XCT_MACRX_HTY_M) == XCT_MACRX_HTY_IPV4_OK) {
skb->ip_summed = CHECKSUM_COMPLETE;
- skb->csum = (dp->macrx & XCT_MACRX_CSUM_M) >>
+ skb->csum = (macrx & XCT_MACRX_CSUM_M) >>
XCT_MACRX_CSUM_S;
} else
skb->ip_summed = CHECKSUM_NONE;
@@ -430,13 +475,13 @@ static int pasemi_mac_clean_rx(struct pa
netif_receive_skb(skb);
- info->dma = 0;
- info->skb = NULL;
dp->ptr = 0;
dp->macrx = 0;
+
+ n++;
}
- mac->rx->next_to_clean += count;
+ mac->rx->next_to_clean += limit - count;
pasemi_mac_replenish_rx_ring(mac->netdev);
spin_unlock(&mac->rx->lock);
@@ -494,18 +539,28 @@ static irqreturn_t pasemi_mac_rx_intr(in
struct pasemi_mac *mac = netdev_priv(dev);
unsigned int reg;
- if (!(*mac->rx_status & PAS_STATUS_INT))
+ if (!(*mac->rx_status & PAS_STATUS_CAUSE_M))
return IRQ_NONE;
- netif_rx_schedule(dev);
- pci_write_config_dword(mac->iob_pdev, PAS_IOB_DMA_COM_TIMEOUTCFG,
- PAS_IOB_DMA_COM_TIMEOUTCFG_TCNT(0));
+ if (*mac->rx_status & PAS_STATUS_ERROR)
+ printk("rx_status reported error\n");
- reg = PAS_IOB_DMA_RXCH_RESET_PINTC | PAS_IOB_DMA_RXCH_RESET_SINTC |
- PAS_IOB_DMA_RXCH_RESET_DINTC;
+ /* Don't reset packet count so it won't fire again but clear
+ * all others.
+ */
+
+ pci_read_config_dword(mac->dma_pdev, PAS_DMA_RXINT_RCMDSTA(mac->dma_if), ®);
+
+ reg = 0;
+ if (*mac->rx_status & PAS_STATUS_SOFT)
+ reg |= PAS_IOB_DMA_RXCH_RESET_SINTC;
+ if (*mac->rx_status & PAS_STATUS_ERROR)
+ reg |= PAS_IOB_DMA_RXCH_RESET_DINTC;
if (*mac->rx_status & PAS_STATUS_TIMER)
reg |= PAS_IOB_DMA_RXCH_RESET_TINTC;
+ netif_rx_schedule(dev);
+
pci_write_config_dword(mac->iob_pdev,
PAS_IOB_DMA_RXCH_RESET(mac->dma_rxch), reg);
@@ -519,14 +574,17 @@ static irqreturn_t pasemi_mac_tx_intr(in
struct pasemi_mac *mac = netdev_priv(dev);
unsigned int reg;
- if (!(*mac->tx_status & PAS_STATUS_INT))
+ if (!(*mac->tx_status & PAS_STATUS_CAUSE_M))
return IRQ_NONE;
pasemi_mac_clean_tx(mac);
- reg = PAS_IOB_DMA_TXCH_RESET_PINTC | PAS_IOB_DMA_TXCH_RESET_SINTC;
- if (*mac->tx_status & PAS_STATUS_TIMER)
- reg |= PAS_IOB_DMA_TXCH_RESET_TINTC;
+ reg = PAS_IOB_DMA_TXCH_RESET_PINTC;
+
+ if (*mac->tx_status & PAS_STATUS_SOFT)
+ reg |= PAS_IOB_DMA_TXCH_RESET_SINTC;
+ if (*mac->tx_status & PAS_STATUS_ERROR)
+ reg |= PAS_IOB_DMA_TXCH_RESET_DINTC;
pci_write_config_dword(mac->iob_pdev, PAS_IOB_DMA_TXCH_RESET(mac->dma_txch),
reg);
@@ -563,10 +621,18 @@ static int pasemi_mac_open(struct net_de
flags |= PAS_MAC_CFG_PCFG_TSR_1G | PAS_MAC_CFG_PCFG_SPD_1G;
pci_write_config_dword(mac->iob_pdev, PAS_IOB_DMA_RXCH_CFG(mac->dma_rxch),
- PAS_IOB_DMA_RXCH_CFG_CNTTH(30));
+ PAS_IOB_DMA_RXCH_CFG_CNTTH(1));
+
+ pci_write_config_dword(mac->iob_pdev, PAS_IOB_DMA_TXCH_CFG(mac->dma_txch),
+ PAS_IOB_DMA_TXCH_CFG_CNTTH(32));
+ /* Clear out any residual packet count state from firmware */
+ pasemi_mac_restart_rx_intr(mac);
+ pasemi_mac_restart_tx_intr(mac);
+
+ /* 0xffffff is max value, about 16ms */
pci_write_config_dword(mac->iob_pdev, PAS_IOB_DMA_COM_TIMEOUTCFG,
- PAS_IOB_DMA_COM_TIMEOUTCFG_TCNT(1000000));
+ PAS_IOB_DMA_COM_TIMEOUTCFG_TCNT(0xffffff));
pci_write_config_dword(mac->pdev, PAS_MAC_CFG_PCFG, flags);
@@ -585,7 +651,7 @@ static int pasemi_mac_open(struct net_de
/* enable rx if */
pci_write_config_dword(mac->dma_pdev,
PAS_DMA_RXINT_RCMDSTA(mac->dma_if),
- PAS_DMA_RXINT_RCMDSTA_EN);
+ PAS_DMA_RXINT_RCMDSTA_EN|PAS_DMA_RXINT_RCMDSTA_MBT);
/* enable rx channel */
pci_write_config_dword(mac->dma_pdev,
@@ -838,18 +904,18 @@ static int pasemi_mac_poll(struct net_de
pkts = pasemi_mac_clean_rx(mac, limit);
+ dev->quota -= pkts;
+ *budget -= pkts;
+
if (pkts < limit) {
/* all done, no more packets present */
netif_rx_complete(dev);
- /* re-enable receive interrupts */
- pci_write_config_dword(mac->iob_pdev, PAS_IOB_DMA_COM_TIMEOUTCFG,
- PAS_IOB_DMA_COM_TIMEOUTCFG_TCNT(1000000));
+ pasemi_mac_restart_rx_intr(mac);
+
return 0;
} else {
/* used up our quantum, so reschedule */
- dev->quota -= pkts;
- *budget -= pkts;
return 1;
}
}
Index: powerpc/drivers/net/pasemi_mac.h
===================================================================
--- powerpc.orig/drivers/net/pasemi_mac.h
+++ powerpc/drivers/net/pasemi_mac.h
@@ -195,11 +195,15 @@ enum {
#define PAS_DMA_RXINT_RCMDSTA(i) (0x200+(i)*_PAS_DMA_RXINT_STRIDE)
#define PAS_DMA_RXINT_RCMDSTA_EN 0x00000001
#define PAS_DMA_RXINT_RCMDSTA_ST 0x00000002
-#define PAS_DMA_RXINT_RCMDSTA_OO 0x00000100
-#define PAS_DMA_RXINT_RCMDSTA_BP 0x00000200
-#define PAS_DMA_RXINT_RCMDSTA_DR 0x00000400
+#define PAS_DMA_RXINT_RCMDSTA_MBT 0x00000008
+#define PAS_DMA_RXINT_RCMDSTA_MDR 0x00000010
+#define PAS_DMA_RXINT_RCMDSTA_MOO 0x00000020
+#define PAS_DMA_RXINT_RCMDSTA_MBP 0x00000040
#define PAS_DMA_RXINT_RCMDSTA_BT 0x00000800
-#define PAS_DMA_RXINT_RCMDSTA_TB 0x00001000
+#define PAS_DMA_RXINT_RCMDSTA_DR 0x00001000
+#define PAS_DMA_RXINT_RCMDSTA_OO 0x00002000
+#define PAS_DMA_RXINT_RCMDSTA_BP 0x00004000
+#define PAS_DMA_RXINT_RCMDSTA_TB 0x00008000
#define PAS_DMA_RXINT_RCMDSTA_ACT 0x00010000
#define PAS_DMA_RXINT_RCMDSTA_DROPS_M 0xfffe0000
#define PAS_DMA_RXINT_RCMDSTA_DROPS_S 17
@@ -299,6 +303,7 @@ enum {
#define PAS_STATUS_DCNT_S 16
#define PAS_STATUS_BPCNT_M 0x0000ffff00000000ull
#define PAS_STATUS_BPCNT_S 32
+#define PAS_STATUS_CAUSE_M 0xf000000000000000ull
#define PAS_STATUS_TIMER 0x1000000000000000ull
#define PAS_STATUS_ERROR 0x2000000000000000ull
#define PAS_STATUS_SOFT 0x4000000000000000ull
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