+Subject: [1/5] e1000e: Fix error path in link detection
+From: Benjamin Poirier <bpoirier@suse.com>
+X-Patchwork-Id: 792259
+Message-Id: <20170721183627.13373-1-bpoirier@suse.com>
+To: Jeff Kirsher <jeffrey.t.kirsher@intel.com>
+Cc: netdev@vger.kernel.org, intel-wired-lan@lists.osuosl.org,
+ linux-kernel@vger.kernel.org,
+ Lennart Sorensen <lsorense@csclub.uwaterloo.ca>
+Date: Fri, 21 Jul 2017 11:36:23 -0700
+
+In case of error from e1e_rphy(), the loop will exit early and "success"
+will be set to true erroneously.
+
+Signed-off-by: Benjamin Poirier <bpoirier@suse.com>
+---
+ drivers/net/ethernet/intel/e1000e/phy.c | 7 ++++---
+ 1 file changed, 4 insertions(+), 3 deletions(-)
+
+diff --git a/drivers/net/ethernet/intel/e1000e/phy.c b/drivers/net/ethernet/intel/e1000e/phy.c
+index d78d47b41a71..86ff0969efb6 100644
+--- a/drivers/net/ethernet/intel/e1000e/phy.c
++++ b/drivers/net/ethernet/intel/e1000e/phy.c
+@@ -1744,6 +1744,7 @@ s32 e1000e_phy_has_link_generic(struct e1000_hw *hw, u32 iterations,
+ s32 ret_val = 0;
+ u16 i, phy_status;
+
++ *success = false;
+ for (i = 0; i < iterations; i++) {
+ /* Some PHYs require the MII_BMSR register to be read
+ * twice due to the link bit being sticky. No harm doing
+@@ -1763,16 +1764,16 @@ s32 e1000e_phy_has_link_generic(struct e1000_hw *hw, u32 iterations,
+ ret_val = e1e_rphy(hw, MII_BMSR, &phy_status);
+ if (ret_val)
+ break;
+- if (phy_status & BMSR_LSTATUS)
++ if (phy_status & BMSR_LSTATUS) {
++ *success = true;
+ break;
++ }
+ if (usec_interval >= 1000)
+ msleep(usec_interval / 1000);
+ else
+ udelay(usec_interval);
+ }
+
+- *success = (i < iterations);
+-
+ return ret_val;
+ }
+
+
+Subject: [2/5] e1000e: Fix wrong comment related to link detection
+From: Benjamin Poirier <bpoirier@suse.com>
+X-Patchwork-Id: 792257
+Message-Id: <20170721183627.13373-2-bpoirier@suse.com>
+To: Jeff Kirsher <jeffrey.t.kirsher@intel.com>
+Cc: netdev@vger.kernel.org, intel-wired-lan@lists.osuosl.org,
+ linux-kernel@vger.kernel.org,
+ Lennart Sorensen <lsorense@csclub.uwaterloo.ca>
+Date: Fri, 21 Jul 2017 11:36:24 -0700
+
+Reading e1000e_check_for_copper_link() shows that get_link_status is set to
+false after link has been detected. Therefore, it stays TRUE until then.
+
+Signed-off-by: Benjamin Poirier <bpoirier@suse.com>
+---
+ drivers/net/ethernet/intel/e1000e/netdev.c | 4 ++--
+ 1 file changed, 2 insertions(+), 2 deletions(-)
+
+diff --git a/drivers/net/ethernet/intel/e1000e/netdev.c b/drivers/net/ethernet/intel/e1000e/netdev.c
+index 2dcb5463d9b8..58a87134d2e5 100644
+--- a/drivers/net/ethernet/intel/e1000e/netdev.c
++++ b/drivers/net/ethernet/intel/e1000e/netdev.c
+@@ -5074,7 +5074,7 @@ static bool e1000e_has_link(struct e1000_adapter *adapter)
+
+ /* get_link_status is set on LSC (link status) interrupt or
+ * Rx sequence error interrupt. get_link_status will stay
+- * false until the check_for_link establishes link
++ * true until the check_for_link establishes link
+ * for copper adapters ONLY
+ */
+ switch (hw->phy.media_type) {
+@@ -5092,7 +5092,7 @@ static bool e1000e_has_link(struct e1000_adapter *adapter)
+ break;
+ case e1000_media_type_internal_serdes:
+ ret_val = hw->mac.ops.check_for_link(hw);
+- link_active = adapter->hw.mac.serdes_has_link;
++ link_active = hw->mac.serdes_has_link;
+ break;
+ default:
+ case e1000_media_type_unknown:
+
+Content-Transfer-Encoding: 7bit
+Subject: [3/5] e1000e: Fix return value test
+From: Benjamin Poirier <bpoirier@suse.com>
+X-Patchwork-Id: 792258
+Message-Id: <20170721183627.13373-3-bpoirier@suse.com>
+To: Jeff Kirsher <jeffrey.t.kirsher@intel.com>
+Cc: netdev@vger.kernel.org, intel-wired-lan@lists.osuosl.org,
+ linux-kernel@vger.kernel.org,
+ Lennart Sorensen <lsorense@csclub.uwaterloo.ca>
+Date: Fri, 21 Jul 2017 11:36:25 -0700
+
+All the helpers return -E1000_ERR_PHY.
+
+Signed-off-by: Benjamin Poirier <bpoirier@suse.com>
+---
+ drivers/net/ethernet/intel/e1000e/netdev.c | 2 +-
+ 1 file changed, 1 insertion(+), 1 deletion(-)
+
+diff --git a/drivers/net/ethernet/intel/e1000e/netdev.c b/drivers/net/ethernet/intel/e1000e/netdev.c
+index 58a87134d2e5..fc6a1d9999b2 100644
+--- a/drivers/net/ethernet/intel/e1000e/netdev.c
++++ b/drivers/net/ethernet/intel/e1000e/netdev.c
+@@ -5099,7 +5099,7 @@ static bool e1000e_has_link(struct e1000_adapter *adapter)
+ break;
+ }
+
+- if ((ret_val == E1000_ERR_PHY) && (hw->phy.type == e1000_phy_igp_3) &&
++ if ((ret_val == -E1000_ERR_PHY) && (hw->phy.type == e1000_phy_igp_3) &&
+ (er32(CTRL) & E1000_PHY_CTRL_GBE_DISABLE)) {
+ /* See e1000_kmrn_lock_loss_workaround_ich8lan() */
+ e_info("Gigabit has been disabled, downgrading speed\n");
+
+Content-Transfer-Encoding: 7bit
+Subject: [4/5] e1000e: Separate signaling for link check/link up
+From: Benjamin Poirier <bpoirier@suse.com>
+X-Patchwork-Id: 792262
+Message-Id: <20170721183627.13373-4-bpoirier@suse.com>
+To: Jeff Kirsher <jeffrey.t.kirsher@intel.com>
+Cc: netdev@vger.kernel.org, intel-wired-lan@lists.osuosl.org,
+ linux-kernel@vger.kernel.org,
+ Lennart Sorensen <lsorense@csclub.uwaterloo.ca>
+Date: Fri, 21 Jul 2017 11:36:26 -0700
+
+Lennart reported the following race condition:
+
+\ e1000_watchdog_task
+ \ e1000e_has_link
+ \ hw->mac.ops.check_for_link() === e1000e_check_for_copper_link
+ /* link is up */
+ mac->get_link_status = false;
+
+ /* interrupt */
+ \ e1000_msix_other
+ hw->mac.get_link_status = true;
+
+ link_active = !hw->mac.get_link_status
+ /* link_active is false, wrongly */
+
+This problem arises because the single flag get_link_status is used to
+signal two different states: link status needs checking and link status is
+down.
+
+Avoid the problem by using the return value of .check_for_link to signal
+the link status to e1000e_has_link().
+
+Reported-by: Lennart Sorensen <lsorense@csclub.uwaterloo.ca>
+Signed-off-by: Benjamin Poirier <bpoirier@suse.com>
+---
+ drivers/net/ethernet/intel/e1000e/mac.c | 11 ++++++++---
+ drivers/net/ethernet/intel/e1000e/netdev.c | 2 +-
+ 2 files changed, 9 insertions(+), 4 deletions(-)
+
+diff --git a/drivers/net/ethernet/intel/e1000e/mac.c b/drivers/net/ethernet/intel/e1000e/mac.c
+index b322011ec282..f457c5703d0c 100644
+--- a/drivers/net/ethernet/intel/e1000e/mac.c
++++ b/drivers/net/ethernet/intel/e1000e/mac.c
+@@ -410,6 +410,9 @@ void e1000e_clear_hw_cntrs_base(struct e1000_hw *hw)
+ * Checks to see of the link status of the hardware has changed. If a
+ * change in link status has been detected, then we read the PHY registers
+ * to get the current speed/duplex if link exists.
++ *
++ * Returns a negative error code (-E1000_ERR_*) or 0 (link down) or 1 (link
++ * up).
+ **/
+ s32 e1000e_check_for_copper_link(struct e1000_hw *hw)
+ {
+@@ -423,7 +426,7 @@ s32 e1000e_check_for_copper_link(struct e1000_hw *hw)
+ * Change or Rx Sequence Error interrupt.
+ */
+ if (!mac->get_link_status)
+- return 0;
++ return 1;
+
+ /* First we want to see if the MII Status Register reports
+ * link. If so, then we want to get the current speed/duplex
+@@ -461,10 +464,12 @@ s32 e1000e_check_for_copper_link(struct e1000_hw *hw)
+ * different link partner.
+ */
+ ret_val = e1000e_config_fc_after_link_up(hw);
+- if (ret_val)
++ if (ret_val) {
+ e_dbg("Error configuring flow control\n");
++ return ret_val;
++ }
+
+- return ret_val;
++ return 1;
+ }
+
+ /**
+diff --git a/drivers/net/ethernet/intel/e1000e/netdev.c b/drivers/net/ethernet/intel/e1000e/netdev.c
+index fc6a1d9999b2..5a8ab1136566 100644
+--- a/drivers/net/ethernet/intel/e1000e/netdev.c
++++ b/drivers/net/ethernet/intel/e1000e/netdev.c
+@@ -5081,7 +5081,7 @@ static bool e1000e_has_link(struct e1000_adapter *adapter)
+ case e1000_media_type_copper:
+ if (hw->mac.get_link_status) {
+ ret_val = hw->mac.ops.check_for_link(hw);
+- link_active = !hw->mac.get_link_status;
++ link_active = ret_val > 0;
+ } else {
+ link_active = true;
+ }
+
+Content-Transfer-Encoding: 7bit
+Subject: [5/5] e1000e: Avoid receiver overrun interrupt bursts
+From: Benjamin Poirier <bpoirier@suse.com>
+X-Patchwork-Id: 792260
+Message-Id: <20170721183627.13373-5-bpoirier@suse.com>
+To: Jeff Kirsher <jeffrey.t.kirsher@intel.com>
+Cc: netdev@vger.kernel.org, intel-wired-lan@lists.osuosl.org,
+ linux-kernel@vger.kernel.org,
+ Lennart Sorensen <lsorense@csclub.uwaterloo.ca>
+Date: Fri, 21 Jul 2017 11:36:27 -0700
+
+When e1000e_poll() is not fast enough to keep up with incoming traffic, the
+adapter (when operating in msix mode) raises the Other interrupt to signal
+Receiver Overrun.
+
+This is a double problem because 1) at the moment e1000_msix_other()
+assumes that it is only called in case of Link Status Change and 2) if the
+condition persists, the interrupt is repeatedly raised again in quick
+succession.
+
+Ideally we would configure the Other interrupt to not be raised in case of
+receiver overrun but this doesn't seem possible on this adapter. Instead,
+we handle the first part of the problem by reverting to the practice of
+reading ICR in the other interrupt handler, like before commit 16ecba59bc33
+("e1000e: Do not read ICR in Other interrupt"). Thanks to commit
+0a8047ac68e5 ("e1000e: Fix msi-x interrupt automask") which cleared IAME
+from CTRL_EXT, reading ICR doesn't interfere with RxQ0, TxQ0 interrupts
+anymore. We handle the second part of the problem by not re-enabling the
+Other interrupt right away when there is overrun. Instead, we wait until
+traffic subsides, napi polling mode is exited and interrupts are
+re-enabled.
+
+Reported-by: Lennart Sorensen <lsorense@csclub.uwaterloo.ca>
+Fixes: 16ecba59bc33 ("e1000e: Do not read ICR in Other interrupt")
+Signed-off-by: Benjamin Poirier <bpoirier@suse.com>
+---
+ drivers/net/ethernet/intel/e1000e/defines.h | 1 +
+ drivers/net/ethernet/intel/e1000e/netdev.c | 33 +++++++++++++++++++++++------
+ 2 files changed, 27 insertions(+), 7 deletions(-)
+
+diff --git a/drivers/net/ethernet/intel/e1000e/defines.h b/drivers/net/ethernet/intel/e1000e/defines.h
+index 0641c0098738..afb7ebe20b24 100644
+--- a/drivers/net/ethernet/intel/e1000e/defines.h
++++ b/drivers/net/ethernet/intel/e1000e/defines.h
+@@ -398,6 +398,7 @@
+ #define E1000_ICR_LSC 0x00000004 /* Link Status Change */
+ #define E1000_ICR_RXSEQ 0x00000008 /* Rx sequence error */
+ #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_ECCER 0x00400000 /* Uncorrectable ECC Error */
+ /* If this bit asserted, the driver should claim the interrupt */
+diff --git a/drivers/net/ethernet/intel/e1000e/netdev.c b/drivers/net/ethernet/intel/e1000e/netdev.c
+index 5a8ab1136566..803edd1a6401 100644
+--- a/drivers/net/ethernet/intel/e1000e/netdev.c
++++ b/drivers/net/ethernet/intel/e1000e/netdev.c
+@@ -1910,12 +1910,30 @@ 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;
++ bool enable = true;
++
++ icr = er32(ICR);
++ if (icr & E1000_ICR_RXO) {
++ ew32(ICR, E1000_ICR_RXO);
++ enable = false;
++ /* napi poll will re-enable Other, make sure it runs */
++ if (napi_schedule_prep(&adapter->napi)) {
++ adapter->total_rx_bytes = 0;
++ adapter->total_rx_packets = 0;
++ __napi_schedule(&adapter->napi);
++ }
++ }
++ 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)) {
++ mod_timer(&adapter->watchdog_timer, jiffies + 1);
++ }
++ }
+
+- hw->mac.get_link_status = true;
+-
+- /* guard against interrupt when we're going down */
+- if (!test_bit(__E1000_DOWN, &adapter->state)) {
+- mod_timer(&adapter->watchdog_timer, jiffies + 1);
++ if (enable && !test_bit(__E1000_DOWN, &adapter->state)) {
+ ew32(IMS, E1000_IMS_OTHER);
+ }
+
+@@ -2687,7 +2705,8 @@ static int e1000e_poll(struct napi_struct *napi, int weight)
+ napi_complete_done(napi, work_done);
+ if (!test_bit(__E1000_DOWN, &adapter->state)) {
+ if (adapter->msix_entries)
+- ew32(IMS, adapter->rx_ring->ims_val);
++ ew32(IMS, adapter->rx_ring->ims_val |
++ E1000_IMS_OTHER);
+ else
+ e1000_irq_enable(adapter);
+ }
+@@ -4204,7 +4223,7 @@ static void e1000e_trigger_lsc(struct e1000_adapter *adapter)
+ struct e1000_hw *hw = &adapter->hw;
+
+ if (adapter->msix_entries)
+- ew32(ICS, E1000_ICS_OTHER);
++ ew32(ICS, E1000_ICS_LSC | E1000_ICS_OTHER);
+ else
+ ew32(ICS, E1000_ICS_LSC);
+ }
projects / openwrt / openwrt.git / commitdiff