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authorBruce Allan <bruce.w.allan@intel.com>2006-12-15 10:39:45 +0100
committerJeff Garzik <jeff@garzik.org>2006-12-26 15:51:30 -0500
commit018ea44ef1eade417296c4a57afe3cd963268433 (patch)
tree1be60d1e3f76f49c7675da5c314576ff601db644 /drivers/net
parentd89b6c6750e7d7527603b573ec60ba787f5c04a6 (diff)
[PATCH] e1000: Fix PBA allocation calculations
Assign the PBA to be large enough to contain at least 2 jumbo frames on all adapters. This dramatically increases performance on several adapters and fixes TX performance degradation issues where the PBA was misallocated in the old algorithm. Signed-off-by: Bruce Allan <bruce.w.allan@intel.com> Signed-off-by: Auke Kok <auke-jan.h.kok@intel.com> Signed-off-by: Arjan van de Ven <arjan@linux.intel.com> Signed-off-by: Jeff Garzik <jeff@garzik.org>
Diffstat (limited to 'drivers/net')
-rw-r--r--drivers/net/e1000/e1000_hw.h1
-rw-r--r--drivers/net/e1000/e1000_main.c99
2 files changed, 86 insertions, 14 deletions
diff --git a/drivers/net/e1000/e1000_hw.h b/drivers/net/e1000/e1000_hw.h
index f4d01e169c4..15b8625c40c 100644
--- a/drivers/net/e1000/e1000_hw.h
+++ b/drivers/net/e1000/e1000_hw.h
@@ -2422,6 +2422,7 @@ struct e1000_host_command_info {
#define E1000_PBA_8K 0x0008 /* 8KB, default Rx allocation */
#define E1000_PBA_12K 0x000C /* 12KB, default Rx allocation */
#define E1000_PBA_16K 0x0010 /* 16KB, default TX allocation */
+#define E1000_PBA_20K 0x0014
#define E1000_PBA_22K 0x0016
#define E1000_PBA_24K 0x0018
#define E1000_PBA_30K 0x001E
diff --git a/drivers/net/e1000/e1000_main.c b/drivers/net/e1000/e1000_main.c
index e04f1ba847f..6c3618d55d1 100644
--- a/drivers/net/e1000/e1000_main.c
+++ b/drivers/net/e1000/e1000_main.c
@@ -661,16 +661,34 @@ e1000_reinit_locked(struct e1000_adapter *adapter)
void
e1000_reset(struct e1000_adapter *adapter)
{
- uint32_t pba;
+ uint32_t pba = 0, tx_space, min_tx_space, min_rx_space;
uint16_t fc_high_water_mark = E1000_FC_HIGH_DIFF;
+ boolean_t legacy_pba_adjust = FALSE;
/* Repartition Pba for greater than 9k mtu
* To take effect CTRL.RST is required.
*/
switch (adapter->hw.mac_type) {
+ case e1000_82542_rev2_0:
+ case e1000_82542_rev2_1:
+ case e1000_82543:
+ case e1000_82544:
+ case e1000_82540:
+ case e1000_82541:
+ case e1000_82541_rev_2:
+ legacy_pba_adjust = TRUE;
+ pba = E1000_PBA_48K;
+ break;
+ case e1000_82545:
+ case e1000_82545_rev_3:
+ case e1000_82546:
+ case e1000_82546_rev_3:
+ pba = E1000_PBA_48K;
+ break;
case e1000_82547:
case e1000_82547_rev_2:
+ legacy_pba_adjust = TRUE;
pba = E1000_PBA_30K;
break;
case e1000_82571:
@@ -679,27 +697,80 @@ e1000_reset(struct e1000_adapter *adapter)
pba = E1000_PBA_38K;
break;
case e1000_82573:
- pba = E1000_PBA_12K;
+ pba = E1000_PBA_20K;
break;
case e1000_ich8lan:
pba = E1000_PBA_8K;
- break;
- default:
- pba = E1000_PBA_48K;
+ case e1000_undefined:
+ case e1000_num_macs:
break;
}
- if ((adapter->hw.mac_type != e1000_82573) &&
- (adapter->netdev->mtu > E1000_RXBUFFER_8192))
- pba -= 8; /* allocate more FIFO for Tx */
+ if (legacy_pba_adjust == TRUE) {
+ if (adapter->netdev->mtu > E1000_RXBUFFER_8192)
+ pba -= 8; /* allocate more FIFO for Tx */
+ if (adapter->hw.mac_type == e1000_82547) {
+ adapter->tx_fifo_head = 0;
+ adapter->tx_head_addr = pba << E1000_TX_HEAD_ADDR_SHIFT;
+ adapter->tx_fifo_size =
+ (E1000_PBA_40K - pba) << E1000_PBA_BYTES_SHIFT;
+ atomic_set(&adapter->tx_fifo_stall, 0);
+ }
+ } else if (adapter->hw.max_frame_size > MAXIMUM_ETHERNET_FRAME_SIZE) {
+ /* adjust PBA for jumbo frames */
+ E1000_WRITE_REG(&adapter->hw, PBA, pba);
+
+ /* To maintain wire speed transmits, the Tx FIFO should be
+ * large enough to accomodate two full transmit packets,
+ * rounded up to the next 1KB and expressed in KB. Likewise,
+ * the Rx FIFO should be large enough to accomodate at least
+ * one full receive packet and is similarly rounded up and
+ * expressed in KB. */
+ pba = E1000_READ_REG(&adapter->hw, PBA);
+ /* upper 16 bits has Tx packet buffer allocation size in KB */
+ tx_space = pba >> 16;
+ /* lower 16 bits has Rx packet buffer allocation size in KB */
+ pba &= 0xffff;
+ /* don't include ethernet FCS because hardware appends/strips */
+ min_rx_space = adapter->netdev->mtu + ENET_HEADER_SIZE +
+ VLAN_TAG_SIZE;
+ min_tx_space = min_rx_space;
+ min_tx_space *= 2;
+ E1000_ROUNDUP(min_tx_space, 1024);
+ min_tx_space >>= 10;
+ E1000_ROUNDUP(min_rx_space, 1024);
+ min_rx_space >>= 10;
+
+ /* If current Tx allocation is less than the min Tx FIFO size,
+ * and the min Tx FIFO size is less than the current Rx FIFO
+ * allocation, take space away from current Rx allocation */
+ if (tx_space < min_tx_space &&
+ ((min_tx_space - tx_space) < pba)) {
+ pba = pba - (min_tx_space - tx_space);
+
+ /* PCI/PCIx hardware has PBA alignment constraints */
+ switch (adapter->hw.mac_type) {
+ case e1000_82545 ... e1000_82546_rev_3:
+ pba &= ~(E1000_PBA_8K - 1);
+ break;
+ default:
+ break;
+ }
- if (adapter->hw.mac_type == e1000_82547) {
- adapter->tx_fifo_head = 0;
- adapter->tx_head_addr = pba << E1000_TX_HEAD_ADDR_SHIFT;
- adapter->tx_fifo_size =
- (E1000_PBA_40K - pba) << E1000_PBA_BYTES_SHIFT;
- atomic_set(&adapter->tx_fifo_stall, 0);
+ /* if short on rx space, rx wins and must trump tx
+ * adjustment or use Early Receive if available */
+ if (pba < min_rx_space) {
+ switch (adapter->hw.mac_type) {
+ case e1000_82573:
+ /* ERT enabled in e1000_configure_rx */
+ break;
+ default:
+ pba = min_rx_space;
+ break;
+ }
+ }
+ }
}
E1000_WRITE_REG(&adapter->hw, PBA, pba);