cxgb4: Fix some small bugs in t4_sge_init_soft() when our Page Size is 64KB

We'd come in with SGE_FL_BUFFER_SIZE[0] and [1] both equal to 64KB and the
extant logic would flag that as an error.

Based on original work by Casey Leedom <leedom@chelsio.com>

Signed-off-by: Kumar Sanghvi <kumaras@chelsio.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 10 insertions, 2 deletions

diff --git a/drivers/net/ethernet/chelsio/cxgb4/sge.c b/drivers/net/ethernet/chelsio/cxgb4/sge.c
index af76b25bb606..3a2ecd84afee 100644
--- a/drivers/net/ethernet/chelsio/cxgb4/sge.c
+++ b/drivers/net/ethernet/chelsio/cxgb4/sge.c
@@ -2596,11 +2596,19 @@ static int t4_sge_init_soft(struct adapter *adap)
         fl_small_mtu = READ_FL_BUF(RX_SMALL_MTU_BUF);
         fl_large_mtu = READ_FL_BUF(RX_LARGE_MTU_BUF);
 
+        /* We only bother using the Large Page logic if the Large Page Buffer
+         * is larger than our Page Size Buffer.
+         */
+        if (fl_large_pg <= fl_small_pg)
+                fl_large_pg = 0;
+
         #undef READ_FL_BUF
 
+        /* The Page Size Buffer must be exactly equal to our Page Size and the
+         * Large Page Size Buffer should be 0 (per above) or a power of 2.
+         */
         if (fl_small_pg != PAGE_SIZE ||
-            (fl_large_pg != 0 && (fl_large_pg < fl_small_pg ||
-                                  (fl_large_pg & (fl_large_pg-1)) != 0))) {
+            (fl_large_pg & (fl_large_pg-1)) != 0) {
                 dev_err(adap->pdev_dev, "bad SGE FL page buffer sizes [%d, %d]\n",
                         fl_small_pg, fl_large_pg);
                 return -EINVAL;