diff --git a/hw/net/lan9118.c b/hw/net/lan9118.c
index 456ae38107..f1cba55967 100644
--- a/hw/net/lan9118.c
+++ b/hw/net/lan9118.c
@@ -696,6 +696,14 @@ static void do_tx_packet(lan9118_state *s)
     n = (s->tx_status_fifo_head + s->tx_status_fifo_used) & 511;
     s->tx_status_fifo[n] = status;
     s->tx_status_fifo_used++;
+
+    /*
+     * Generate TSFL interrupt if TX FIFO level exceeds the level
+     * specified in the FIFO_INT TX Status Level field.
+     */
+    if (s->tx_status_fifo_used > ((s->fifo_int >> 16) & 0xff)) {
+        s->int_sts |= TSFL_INT;
+    }
     if (s->tx_status_fifo_used == 512) {
         s->int_sts |= TSFF_INT;
         /* TODO: Stop transmission.  */