bnx2x: add gro_check
The patch provides workaround for BUG in FW 7.2.16,
which in GRO mode may miscalculate buffer and
place on SGE one frag less than it could.
It may happen only for some MTUs, we mark these MTUs
with gro_check flag during device initialization or
MTU change.
Next FW should include fix for the issue and the
patch could be reverted.
Signed-off-by: Dmitry Kravkov <dmitry@broadcom.com>
Signed-off-by: Eilon Greenstein <eilong@broadcom.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/drivers/net/ethernet/broadcom/bnx2x/bnx2x.h b/drivers/net/ethernet/broadcom/bnx2x/bnx2x.h
index 3cf9df8..6ebb55d 100644
--- a/drivers/net/ethernet/broadcom/bnx2x/bnx2x.h
+++ b/drivers/net/ethernet/broadcom/bnx2x/bnx2x.h
@@ -341,6 +341,7 @@
#define SGE_PAGE_SIZE PAGE_SIZE
#define SGE_PAGE_SHIFT PAGE_SHIFT
#define SGE_PAGE_ALIGN(addr) PAGE_ALIGN((typeof(PAGE_SIZE))(addr))
+#define SGE_PAGES (SGE_PAGE_SIZE * PAGES_PER_SGE)
/* SGE ring related macros */
#define NUM_RX_SGE_PAGES 2
@@ -1210,6 +1211,7 @@
#define ETH_MAX_JUMBO_PACKET_SIZE 9600
/* TCP with Timestamp Option (32) + IPv6 (40) */
#define ETH_MAX_TPA_HEADER_SIZE 72
+#define ETH_MIN_TPA_HEADER_SIZE 40
/* Max supported alignment is 256 (8 shift) */
#define BNX2X_RX_ALIGN_SHIFT min(8, L1_CACHE_SHIFT)
@@ -1329,6 +1331,8 @@
u8 wol;
+ bool gro_check;
+
int rx_ring_size;
u16 tx_quick_cons_trip_int;
diff --git a/drivers/net/ethernet/broadcom/bnx2x/bnx2x_cmn.c b/drivers/net/ethernet/broadcom/bnx2x/bnx2x_cmn.c
index 0a45251..f82dfff5 100644
--- a/drivers/net/ethernet/broadcom/bnx2x/bnx2x_cmn.c
+++ b/drivers/net/ethernet/broadcom/bnx2x/bnx2x_cmn.c
@@ -330,6 +330,16 @@
u16 gro_size = le16_to_cpu(cqe->pkt_len_or_gro_seg_len);
tpa_info->full_page =
SGE_PAGE_SIZE * PAGES_PER_SGE / gro_size * gro_size;
+ /*
+ * FW 7.2.16 BUG workaround:
+ * if SGE size is (exactly) multiple gro_size
+ * fw will place one less frag on SGE.
+ * the calculation is done only for potentially
+ * dangerous MTUs.
+ */
+ if (unlikely(bp->gro_check))
+ if (!(SGE_PAGE_SIZE * PAGES_PER_SGE % gro_size))
+ tpa_info->full_page -= gro_size;
tpa_info->gro_size = gro_size;
}
@@ -3486,6 +3496,8 @@
*/
dev->mtu = new_mtu;
+ bp->gro_check = bnx2x_need_gro_check(new_mtu);
+
return bnx2x_reload_if_running(dev);
}
diff --git a/drivers/net/ethernet/broadcom/bnx2x/bnx2x_cmn.h b/drivers/net/ethernet/broadcom/bnx2x/bnx2x_cmn.h
index d2093ee..33aa7de 100644
--- a/drivers/net/ethernet/broadcom/bnx2x/bnx2x_cmn.h
+++ b/drivers/net/ethernet/broadcom/bnx2x/bnx2x_cmn.h
@@ -1504,6 +1504,13 @@
*/
return mtu <= SGE_PAGE_SIZE && (U_ETH_SGL_SIZE * fpp) <= MAX_SKB_FRAGS;
}
+
+static inline bool bnx2x_need_gro_check(int mtu)
+{
+ return (SGE_PAGES / (mtu - ETH_MAX_TPA_HEADER_SIZE - 1)) !=
+ (SGE_PAGES / (mtu - ETH_MIN_TPA_HEADER_SIZE + 1));
+}
+
/**
* bnx2x_bz_fp - zero content of the fastpath structure.
*
diff --git a/drivers/net/ethernet/broadcom/bnx2x/bnx2x_main.c b/drivers/net/ethernet/broadcom/bnx2x/bnx2x_main.c
index 816e7d4..b4afef6 100644
--- a/drivers/net/ethernet/broadcom/bnx2x/bnx2x_main.c
+++ b/drivers/net/ethernet/broadcom/bnx2x/bnx2x_main.c
@@ -10214,6 +10214,8 @@
if (CHIP_IS_E3B0(bp))
bp->max_cos = BNX2X_MULTI_TX_COS_E3B0;
+ bp->gro_check = bnx2x_need_gro_check(bp->dev->mtu);
+
return rc;
}