e1000e: disable Early Receive DMA on ICH LOMs
Internal stress testing with jumbo frames shows the reliability of ICH9 and
ICH10D devices is improved in certain corner cases by disabling the Early
Receive feature. To reduce the performance impact caused by disabling this
feature, the packet buffer sizes and relevant flow control settings are
modified accordingly.
Signed-off-by: Bruce Allan <bruce.w.allan@intel.com>
Tested-by: Aaron Brown <aaron.f.brown@intel.com>
Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>
diff --git a/drivers/net/ethernet/intel/e1000e/netdev.c b/drivers/net/ethernet/intel/e1000e/netdev.c
index 89af6c0..49b5ded 100644
--- a/drivers/net/ethernet/intel/e1000e/netdev.c
+++ b/drivers/net/ethernet/intel/e1000e/netdev.c
@@ -2947,8 +2947,7 @@
* per packet.
*/
pages = PAGE_USE_COUNT(adapter->netdev->mtu);
- if (!(adapter->flags & FLAG_HAS_ERT) && (pages <= 3) &&
- (PAGE_SIZE <= 16384) && (rctl & E1000_RCTL_LPE))
+ if ((pages <= 3) && (PAGE_SIZE <= 16384) && (rctl & E1000_RCTL_LPE))
adapter->rx_ps_pages = pages;
else
adapter->rx_ps_pages = 0;
@@ -3095,23 +3094,14 @@
}
ew32(RXCSUM, rxcsum);
- /*
- * Enable early receives on supported devices, only takes effect when
- * packet size is equal or larger than the specified value (in 8 byte
- * units), e.g. using jumbo frames when setting to E1000_ERT_2048
- */
- if ((adapter->flags & FLAG_HAS_ERT) ||
- (adapter->hw.mac.type == e1000_pch2lan)) {
+ if (adapter->hw.mac.type == e1000_pch2lan) {
+ /*
+ * With jumbo frames, excessive C-state transition
+ * latencies result in dropped transactions.
+ */
if (adapter->netdev->mtu > ETH_DATA_LEN) {
u32 rxdctl = er32(RXDCTL(0));
ew32(RXDCTL(0), rxdctl | 0x3);
- if (adapter->flags & FLAG_HAS_ERT)
- ew32(ERT, E1000_ERT_2048 | (1 << 13));
- /*
- * With jumbo frames and early-receive enabled,
- * excessive C-state transition latencies result in
- * dropped transactions.
- */
pm_qos_update_request(&adapter->netdev->pm_qos_req, 55);
} else {
pm_qos_update_request(&adapter->netdev->pm_qos_req,
@@ -3422,9 +3412,7 @@
* if short on Rx space, Rx wins and must trump Tx
* adjustment or use Early Receive if available
*/
- if ((pba < min_rx_space) &&
- (!(adapter->flags & FLAG_HAS_ERT)))
- /* ERT enabled in e1000_configure_rx */
+ if (pba < min_rx_space)
pba = min_rx_space;
}
@@ -3438,8 +3426,6 @@
* (or the size used for early receive) above it in the Rx FIFO.
* Set it to the lower of:
* - 90% of the Rx FIFO size, and
- * - the full Rx FIFO size minus the early receive size (for parts
- * with ERT support assuming ERT set to E1000_ERT_2048), or
* - the full Rx FIFO size minus one full frame
*/
if (adapter->flags & FLAG_DISABLE_FC_PAUSE_TIME)
@@ -3450,14 +3436,19 @@
fc->current_mode = fc->requested_mode;
switch (hw->mac.type) {
+ case e1000_ich9lan:
+ case e1000_ich10lan:
+ if (adapter->netdev->mtu > ETH_DATA_LEN) {
+ pba = 14;
+ ew32(PBA, pba);
+ fc->high_water = 0x2800;
+ fc->low_water = fc->high_water - 8;
+ break;
+ }
+ /* fall-through */
default:
- if ((adapter->flags & FLAG_HAS_ERT) &&
- (adapter->netdev->mtu > ETH_DATA_LEN))
- hwm = min(((pba << 10) * 9 / 10),
- ((pba << 10) - (E1000_ERT_2048 << 3)));
- else
- hwm = min(((pba << 10) * 9 / 10),
- ((pba << 10) - adapter->max_frame_size));
+ hwm = min(((pba << 10) * 9 / 10),
+ ((pba << 10) - adapter->max_frame_size));
fc->high_water = hwm & E1000_FCRTH_RTH; /* 8-byte granularity */
fc->low_water = fc->high_water - 8;
@@ -3490,11 +3481,10 @@
/*
* Disable Adaptive Interrupt Moderation if 2 full packets cannot
- * fit in receive buffer and early-receive not supported.
+ * fit in receive buffer.
*/
if (adapter->itr_setting & 0x3) {
- if (((adapter->max_frame_size * 2) > (pba << 10)) &&
- !(adapter->flags & FLAG_HAS_ERT)) {
+ if ((adapter->max_frame_size * 2) > (pba << 10)) {
if (!(adapter->flags2 & FLAG2_DISABLE_AIM)) {
dev_info(&adapter->pdev->dev,
"Interrupt Throttle Rate turned off\n");
@@ -3862,9 +3852,8 @@
E1000_MNG_DHCP_COOKIE_STATUS_VLAN))
e1000_update_mng_vlan(adapter);
- /* DMA latency requirement to workaround early-receive/jumbo issue */
- if ((adapter->flags & FLAG_HAS_ERT) ||
- (adapter->hw.mac.type == e1000_pch2lan))
+ /* DMA latency requirement to workaround jumbo issue */
+ if (adapter->hw.mac.type == e1000_pch2lan)
pm_qos_add_request(&adapter->netdev->pm_qos_req,
PM_QOS_CPU_DMA_LATENCY,
PM_QOS_DEFAULT_VALUE);
@@ -3975,8 +3964,7 @@
!test_bit(__E1000_TESTING, &adapter->state))
e1000e_release_hw_control(adapter);
- if ((adapter->flags & FLAG_HAS_ERT) ||
- (adapter->hw.mac.type == e1000_pch2lan))
+ if (adapter->hw.mac.type == e1000_pch2lan)
pm_qos_remove_request(&adapter->netdev->pm_qos_req);
pm_runtime_put_sync(&pdev->dev);