[PATCH net-next 2/5] ionic: Report "link_down_events_phy" in ethtool statistics

[Eric Joyner <eric.joyner@amd.com>]

The number of times that link has gone down at the port level is tracked
by the firmware and sent to the driver via regular DMA writes to an
instance of struct ionic_port_status in the driver's memory.

This statistic was never reported, but it is useful for diagnostics, so
add it to the "ethtool -S` stats output, grouped with the other
port-level stats that are contained in struct ionic_port_stats.

Assisted-by: Claude:claude-4.6-sonnet
Signed-off-by: Eric Joyner <eric.joyner@amd.com>
---
 drivers/net/ethernet/pensando/ionic/ionic_stats.c | 6 +++++-
 1 file changed, 5 insertions(+), 1 deletion(-)

diff --git a/drivers/net/ethernet/pensando/ionic/ionic_stats.c b/drivers/net/ethernet/pensando/ionic/ionic_stats.c
index 0107599a9dd4..8f39f687a39f 100644
--- a/drivers/net/ethernet/pensando/ionic/ionic_stats.c
+++ b/drivers/net/ethernet/pensando/ionic/ionic_stats.c
@@ -167,6 +167,7 @@ static const struct ionic_stat_desc ionic_rx_stats_desc[] = {
 #define IONIC_NUM_PORT_STATS ARRAY_SIZE(ionic_port_stats_desc)
 #define IONIC_NUM_TX_STATS ARRAY_SIZE(ionic_tx_stats_desc)
 #define IONIC_NUM_RX_STATS ARRAY_SIZE(ionic_rx_stats_desc)
+#define IONIC_NUM_EXTRA_PORT_STATS	1
 
 #define MAX_Q(lif)   ((lif)->netdev->real_num_tx_queues)
 
@@ -243,7 +244,7 @@ static u64 ionic_sw_stats_get_count(struct ionic_lif *lif)
 		rx_queues += 1;
 
 	total += IONIC_NUM_LIF_STATS;
-	total += IONIC_NUM_PORT_STATS;
+	total += IONIC_NUM_PORT_STATS + IONIC_NUM_EXTRA_PORT_STATS;
 
 	total += tx_queues * IONIC_NUM_TX_STATS;
 	total += rx_queues * IONIC_NUM_RX_STATS;
@@ -280,6 +281,7 @@ static void ionic_sw_stats_get_strings(struct ionic_lif *lif, u8 **buf)
 
 	for (i = 0; i < IONIC_NUM_PORT_STATS; i++)
 		ethtool_puts(buf, ionic_port_stats_desc[i].name);
+	ethtool_puts(buf, "link_down_events_phy");
 
 	for (q_num = 0; q_num < MAX_Q(lif); q_num++)
 		ionic_sw_stats_get_tx_strings(lif, buf, q_num);
@@ -341,6 +343,8 @@ static void ionic_sw_stats_get_values(struct ionic_lif *lif, u64 **buf)
 					     &ionic_port_stats_desc[i]);
 		(*buf)++;
 	}
+	**buf = le16_to_cpu(lif->ionic->idev.port_info->status.link_down_count);
+	(*buf)++;
 
 	for (q_num = 0; q_num < MAX_Q(lif); q_num++)
 		ionic_sw_stats_get_txq_values(lif, buf, q_num);
-- 
2.17.1