[PATCH net-queue 3/3] e1000e: Avoid missed interrupts following ICR read.
From: Benjamin Poirier
Date: Thu Feb 08 2018 - 01:47:37 EST
The 82574 specification update errata 12 states that interrupts may be
missed if ICR is read while INT_ASSERTED is not set. Avoid that problem by
setting all bits related to events that can trigger the Other interrupt in
IMS.
The Other interrupt is raised for such events regardless of whether or not
they are set in IMS. However, only when they are set is the INT_ASSERTED
bit also set in ICR.
By doing this, we ensure that INT_ASSERTED is always set when we read ICR
in e1000_msix_other() and steer clear of the errata. This also ensures that
ICR will automatically be cleared on read, therefore we no longer need to
clear bits explicitly.
Signed-off-by: Benjamin Poirier <bpoirier@xxxxxxxx>
---
drivers/net/ethernet/intel/e1000e/defines.h | 21 ++++++++++++++++++++-
drivers/net/ethernet/intel/e1000e/netdev.c | 11 ++++-------
2 files changed, 24 insertions(+), 8 deletions(-)
diff --git a/drivers/net/ethernet/intel/e1000e/defines.h b/drivers/net/ethernet/intel/e1000e/defines.h
index afb7ebe20b24..824fd44e25f0 100644
--- a/drivers/net/ethernet/intel/e1000e/defines.h
+++ b/drivers/net/ethernet/intel/e1000e/defines.h
@@ -400,6 +400,10 @@
#define E1000_ICR_RXDMT0 0x00000010 /* Rx desc min. threshold (0) */
#define E1000_ICR_RXO 0x00000040 /* Receiver Overrun */
#define E1000_ICR_RXT0 0x00000080 /* Rx timer intr (ring 0) */
+#define E1000_ICR_MDAC 0x00000200 /* MDIO Access Complete */
+#define E1000_ICR_SRPD 0x00010000 /* Small Receive Packet Detected */
+#define E1000_ICR_ACK 0x00020000 /* Receive ACK Frame Detected */
+#define E1000_ICR_MNG 0x00040000 /* Manageability Event Detected */
#define E1000_ICR_ECCER 0x00400000 /* Uncorrectable ECC Error */
/* If this bit asserted, the driver should claim the interrupt */
#define E1000_ICR_INT_ASSERTED 0x80000000
@@ -407,7 +411,7 @@
#define E1000_ICR_RXQ1 0x00200000 /* Rx Queue 1 Interrupt */
#define E1000_ICR_TXQ0 0x00400000 /* Tx Queue 0 Interrupt */
#define E1000_ICR_TXQ1 0x00800000 /* Tx Queue 1 Interrupt */
-#define E1000_ICR_OTHER 0x01000000 /* Other Interrupts */
+#define E1000_ICR_OTHER 0x01000000 /* Other Interrupt */
/* PBA ECC Register */
#define E1000_PBA_ECC_COUNTER_MASK 0xFFF00000 /* ECC counter mask */
@@ -431,12 +435,27 @@
E1000_IMS_RXSEQ | \
E1000_IMS_LSC)
+/* These are all of the events related to the OTHER interrupt.
+ */
+#define IMS_OTHER_MASK ( \
+ E1000_IMS_LSC | \
+ E1000_IMS_RXO | \
+ E1000_IMS_MDAC | \
+ E1000_IMS_SRPD | \
+ E1000_IMS_ACK | \
+ E1000_IMS_MNG)
+
/* Interrupt Mask Set */
#define E1000_IMS_TXDW E1000_ICR_TXDW /* Transmit desc written back */
#define E1000_IMS_LSC E1000_ICR_LSC /* Link Status Change */
#define E1000_IMS_RXSEQ E1000_ICR_RXSEQ /* Rx sequence error */
#define E1000_IMS_RXDMT0 E1000_ICR_RXDMT0 /* Rx desc min. threshold */
+#define E1000_IMS_RXO E1000_ICR_RXO /* Receiver Overrun */
#define E1000_IMS_RXT0 E1000_ICR_RXT0 /* Rx timer intr */
+#define E1000_IMS_MDAC E1000_ICR_MDAC /* MDIO Access Complete */
+#define E1000_IMS_SRPD E1000_ICR_SRPD /* Small Receive Packet */
+#define E1000_IMS_ACK E1000_ICR_ACK /* Receive ACK Frame Detected */
+#define E1000_IMS_MNG E1000_ICR_MNG /* Manageability Event */
#define E1000_IMS_ECCER E1000_ICR_ECCER /* Uncorrectable ECC Error */
#define E1000_IMS_RXQ0 E1000_ICR_RXQ0 /* Rx Queue 0 Interrupt */
#define E1000_IMS_RXQ1 E1000_ICR_RXQ1 /* Rx Queue 1 Interrupt */
diff --git a/drivers/net/ethernet/intel/e1000e/netdev.c b/drivers/net/ethernet/intel/e1000e/netdev.c
index 2c9609bee2ae..9fd4050a91ca 100644
--- a/drivers/net/ethernet/intel/e1000e/netdev.c
+++ b/drivers/net/ethernet/intel/e1000e/netdev.c
@@ -1914,16 +1914,12 @@ static irqreturn_t e1000_msix_other(int __always_unused irq, void *data)
struct net_device *netdev = data;
struct e1000_adapter *adapter = netdev_priv(netdev);
struct e1000_hw *hw = &adapter->hw;
- u32 icr;
-
- icr = er32(ICR);
- ew32(ICR, E1000_ICR_OTHER);
+ u32 icr = er32(ICR);
if (icr & adapter->eiac_mask)
ew32(ICS, (icr & adapter->eiac_mask));
if (icr & E1000_ICR_LSC) {
- ew32(ICR, E1000_ICR_LSC);
hw->mac.get_link_status = true;
/* guard against interrupt when we're going down */
if (!test_bit(__E1000_DOWN, &adapter->state))
@@ -1931,7 +1927,7 @@ static irqreturn_t e1000_msix_other(int __always_unused irq, void *data)
}
if (!test_bit(__E1000_DOWN, &adapter->state))
- ew32(IMS, E1000_IMS_OTHER);
+ ew32(IMS, E1000_IMS_OTHER | IMS_OTHER_MASK);
return IRQ_HANDLED;
}
@@ -2258,7 +2254,8 @@ static void e1000_irq_enable(struct e1000_adapter *adapter)
if (adapter->msix_entries) {
ew32(EIAC_82574, adapter->eiac_mask & E1000_EIAC_MASK_82574);
- ew32(IMS, adapter->eiac_mask | E1000_IMS_OTHER | E1000_IMS_LSC);
+ ew32(IMS, adapter->eiac_mask | E1000_IMS_OTHER |
+ IMS_OTHER_MASK);
} else if (hw->mac.type >= e1000_pch_lpt) {
ew32(IMS, IMS_ENABLE_MASK | E1000_IMS_ECCER);
} else {
--
2.16.1