[PATCH v3] ixgbe: support link speed auto-neg on x550em_x

[Wenzhuo Lu <wenzhuo.lu@intel.com>]

Normally the auto-negotiation is supported by FW. SW need not care about
that. But on x550em_x, FW doesn't support auto-neg. As the ports of x550em_x
are 10G, if we connect the port will a peer which is 1G, the link will always
be down.
We need support auto-neg by SW to avoid this link down issue. As we already
have the code to handle the link speed setting, what we need is a trigger.
When the advertised link speed changes, a PHY interruption will be triggered.
So, we should handle this interruption and call ixgbe_handle_lasi to set the
link speed correctly.

Please be aware it's working when auto-neg is on. If the auto-neg of the peer
port is turned off and its speed is indicated manually, we should also set
the speed of our own port manually.

V2:
 *Fix the wrong signoff name.

V3:
 *Change the tittle and add the explanation of the implementation in commit log.

Signed-off-by: Wenzhuo Lu <wenzhuo.lu@intel.com>
Acked-by: Shaopeng He <shaopeng.he@intel.com>
---
 doc/guides/rel_notes/release_16_04.rst |  8 +++++++
 drivers/net/ixgbe/ixgbe_ethdev.c       | 38 ++++++++++++++++++++++++++++++++++
 drivers/net/ixgbe/ixgbe_ethdev.h       |  1 +
 3 files changed, 47 insertions(+)

diff --git a/doc/guides/rel_notes/release_16_04.rst b/doc/guides/rel_notes/release_16_04.rst
index 8273817..fbdf286 100644
--- a/doc/guides/rel_notes/release_16_04.rst
+++ b/doc/guides/rel_notes/release_16_04.rst
@@ -46,6 +46,14 @@ This section should contain new features added in this release. Sample format:
 
 * **Added vhost-user live migration support.**
 
+* **Supported link speed auto-negotiation on X550EM_X**
+
+  Normally the auto-negotiation is supported by FW. SW need not care about
+  that. But on x550em_x, FW doesn't support auto-neg. As the ports of x550em_x
+  are 10G, if we connect the port will a peer which is 1G, the link will always
+  be down.
+  We added the support of auto-neg by SW to avoid this link down issue.
+
 
 Resolved Issues
 ---------------
diff --git a/drivers/net/ixgbe/ixgbe_ethdev.c b/drivers/net/ixgbe/ixgbe_ethdev.c
index 3e6fe86..2384ba7 100644
--- a/drivers/net/ixgbe/ixgbe_ethdev.c
+++ b/drivers/net/ixgbe/ixgbe_ethdev.c
@@ -1961,6 +1961,25 @@ ixgbe_dev_configure(struct rte_eth_dev *dev)
 	return 0;
 }
 
+static void
+ixgbe_dev_phy_intr_setup(struct rte_eth_dev *dev)
+{
+	struct ixgbe_hw *hw =
+		IXGBE_DEV_PRIVATE_TO_HW(dev->data->dev_private);
+	struct ixgbe_interrupt *intr =
+		IXGBE_DEV_PRIVATE_TO_INTR(dev->data->dev_private);
+	uint32_t gpie;
+
+	/* only set up it on X550EM_X */
+	if (hw->mac.type == ixgbe_mac_X550EM_x) {
+		gpie = IXGBE_READ_REG(hw, IXGBE_GPIE);
+		gpie |= IXGBE_SDP0_GPIEN_X550EM_x;
+		IXGBE_WRITE_REG(hw, IXGBE_GPIE, gpie);
+		if (hw->phy.type == ixgbe_phy_x550em_ext_t)
+			intr->mask |= IXGBE_EICR_GPI_SDP0_X550EM_x;
+	}
+}
+
 /*
  * Configure device link speed and setup link.
  * It returns 0 on success.
@@ -2009,6 +2028,8 @@ ixgbe_dev_start(struct rte_eth_dev *dev)
 	/* configure PF module if SRIOV enabled */
 	ixgbe_pf_host_configure(dev);
 
+	ixgbe_dev_phy_intr_setup(dev);
+
 	/* check and configure queue intr-vector mapping */
 	if ((rte_intr_cap_multiple(intr_handle) ||
 	     !RTE_ETH_DEV_SRIOV(dev).active) &&
@@ -3082,6 +3103,11 @@ ixgbe_dev_interrupt_get_status(struct rte_eth_dev *dev)
 	if (eicr & IXGBE_EICR_MAILBOX)
 		intr->flags |= IXGBE_FLAG_MAILBOX;
 
+	if (hw->mac.type ==  ixgbe_mac_X550EM_x &&
+	    hw->phy.type == ixgbe_phy_x550em_ext_t &&
+	    (eicr & IXGBE_EICR_GPI_SDP0_X550EM_x))
+		intr->flags |= IXGBE_FLAG_PHY_INTERRUPT;
+
 	return 0;
 }
 
@@ -3137,6 +3163,8 @@ ixgbe_dev_interrupt_action(struct rte_eth_dev *dev)
 	int64_t timeout;
 	struct rte_eth_link link;
 	int intr_enable_delay = false;
+	struct ixgbe_hw *hw =
+		IXGBE_DEV_PRIVATE_TO_HW(dev->data->dev_private);
 
 	PMD_DRV_LOG(DEBUG, "intr action type %d", intr->flags);
 
@@ -3145,6 +3173,11 @@ ixgbe_dev_interrupt_action(struct rte_eth_dev *dev)
 		intr->flags &= ~IXGBE_FLAG_MAILBOX;
 	}
 
+	if (intr->flags & IXGBE_FLAG_PHY_INTERRUPT) {
+		ixgbe_handle_lasi(hw);
+		intr->flags &= ~IXGBE_FLAG_PHY_INTERRUPT;
+	}
+
 	if (intr->flags & IXGBE_FLAG_NEED_LINK_UPDATE) {
 		/* get the link status before link update, for predicting later */
 		memset(&link, 0, sizeof(link));
@@ -3208,6 +3241,11 @@ ixgbe_dev_interrupt_delayed_handler(void *param)
 	if (eicr & IXGBE_EICR_MAILBOX)
 		ixgbe_pf_mbx_process(dev);
 
+	if (intr->flags & IXGBE_FLAG_PHY_INTERRUPT) {
+		ixgbe_handle_lasi(hw);
+		intr->flags &= ~IXGBE_FLAG_PHY_INTERRUPT;
+	}
+
 	if (intr->flags & IXGBE_FLAG_NEED_LINK_UPDATE) {
 		ixgbe_dev_link_update(dev, 0);
 		intr->flags &= ~IXGBE_FLAG_NEED_LINK_UPDATE;
diff --git a/drivers/net/ixgbe/ixgbe_ethdev.h b/drivers/net/ixgbe/ixgbe_ethdev.h
index d26771a..5c3aa16 100644
--- a/drivers/net/ixgbe/ixgbe_ethdev.h
+++ b/drivers/net/ixgbe/ixgbe_ethdev.h
@@ -42,6 +42,7 @@
 /* need update link, bit flag */
 #define IXGBE_FLAG_NEED_LINK_UPDATE (uint32_t)(1 << 0)
 #define IXGBE_FLAG_MAILBOX          (uint32_t)(1 << 1)
+#define IXGBE_FLAG_PHY_INTERRUPT    (uint32_t)(1 << 2)
 
 /*
  * Defines that were not part of ixgbe_type.h as they are not used by the
-- 
1.9.3