1 files changed, 27 insertions, 0 deletions
diff --git a/drivers/net/ethernet/meta/fbnic/fbnic_hw_stats.c b/drivers/net/ethernet/meta/fbnic/fbnic_hw_stats.c
new file mode 100644
index 000000000000..a0acc7606aa1
--- /dev/null
+++ b/drivers/net/ethernet/meta/fbnic/fbnic_hw_stats.c
@@ -0,0 +1,27 @@
+#include "fbnic.h"
+
+u64 fbnic_stat_rd64(struct fbnic_dev *fbd, u32 reg, u32 offset)
+{
+	u32 prev_upper, upper, lower, diff;
+
+	prev_upper = rd32(fbd, reg + offset);
+	lower = rd32(fbd, reg);
+	upper = rd32(fbd, reg + offset);
+
+	diff = upper - prev_upper;
+	if (!diff)
+		return ((u64)upper << 32) | lower;
+
+	if (diff > 1)
+		dev_warn_once(fbd->dev,
+			      "Stats inconsistent, upper 32b of %#010x updating too quickly\n",
+			      reg * 4);
+
+	/* Return only the upper bits as we cannot guarantee
+	 * the accuracy of the lower bits. We will add them in
+	 * when the counter slows down enough that we can get
+	 * a snapshot with both upper values being the same
+	 * between reads.
+	 */
+	return ((u64)upper << 32);
+}