[PATCH v4 1/7] ether: add function to query for link state interrupt

[Stephen Hemminger <stephen-OTpzqLSitTUnbdJkjeBofR2eb7JE58TQ@public.gmane.org>]

From: Stephen Hemminger <shemming-43mecJUBy8ZBDgjK7y7TUQ@public.gmane.org>

Allow application to query whether link state will work.
This is also part of abstracting dependency on PCI.

Signed-off-by: Stephen Hemminger <stephen-OTpzqLSitTUnbdJkjeBofR2eb7JE58TQ@public.gmane.org>
---
 lib/librte_ether/rte_ethdev.c | 14 ++++++++++++++
 lib/librte_ether/rte_ethdev.h | 12 ++++++++++++
 2 files changed, 26 insertions(+)

diff --git a/lib/librte_ether/rte_ethdev.c b/lib/librte_ether/rte_ethdev.c
index e20cca5..9577d17 100644
--- a/lib/librte_ether/rte_ethdev.c
+++ b/lib/librte_ether/rte_ethdev.c
@@ -1340,6 +1340,20 @@ rte_eth_dev_start(uint8_t port_id)
 	return 0;
 }
 
+int
+rte_eth_has_link_state(uint8_t port_id)
+{
+	struct rte_eth_dev *dev;
+
+	if (port_id >= nb_ports) {
+		PMD_DEBUG_TRACE("Invalid port_id=%d\n", port_id);
+		return 0;
+	}
+	dev = &rte_eth_devices[port_id];
+
+	return (dev->pci_dev->driver->drv_flags & RTE_PCI_DRV_INTR_LSC) != 0;
+}
+
 void
 rte_eth_dev_stop(uint8_t port_id)
 {
diff --git a/lib/librte_ether/rte_ethdev.h b/lib/librte_ether/rte_ethdev.h
index 4648290..991023b 100644
--- a/lib/librte_ether/rte_ethdev.h
+++ b/lib/librte_ether/rte_ethdev.h
@@ -2064,6 +2064,18 @@ extern void rte_eth_link_get_nowait(uint8_t port_id,
 				struct rte_eth_link *link);
 
 /**
+ * Test whether device supports link state interrupt mode.
+ *
+ * @param port_id
+ *   The port identifier of the Ethernet device.
+ * @return
+ *   - (1) if link state interrupt is supported
+ *   - (0) if link state interrupt is not supported
+ */
+extern int
+rte_eth_has_link_state(uint8_t port_id);
+
+/**
  * Retrieve the general I/O statistics of an Ethernet device.
  *
  * @param port_id
-- 
2.1.4