bnxt_en: Fix GSO type for HW GRO packets on 5750X chips

The existing code is using RSS profile to determine IPV4/IPV6 GSO type
on all chips older than 5760X.  This won't work on 5750X chips that may
be using modified RSS profiles.  This commit from 2018 has updated the
driver to not use RSS profile for HW GRO packets on newer chips:

50f011b ("bnxt_en: Update RSS setup and GRO-HW logic according to the latest spec.")

However, a recent commit to add support for the newest 5760X chip broke
the logic.  If the GRO packet needs to be re-segmented by the stack, the
wrong GSO type will cause the packet to be dropped.

Fix it to only use RSS profile to determine GSO type on the oldest
5730X/5740X chips which cannot use the new method and is safe to use the
RSS profiles.

Also fix the L3/L4 hash type for RX packets by not using the RSS
profile for the same reason.  Use the ITYPE field in the RX completion
to determine L3/L4 hash types correctly.

Fixes: a7445d6 ("bnxt_en: Add support for new RX and TPA_START completion types for P7")
Reviewed-by: Colin Winegarden <[email protected]>
Reviewed-by: Somnath Kotur <[email protected]>
Reviewed-by: Kalesh AP <[email protected]>
Signed-off-by: Michael Chan <[email protected]>
Link: https://patch.msgid.link/[email protected]
Signed-off-by: Jakub Kicinski <[email protected]>

Author: Michael Chan

drivers/net/ethernet/broadcom/bnxt/bnxt.c

@@ -1531,7 +1531,7 @@ static void bnxt_tpa_start(struct bnxt *bp, struct bnxt_rx_ring_info *rxr,
 		if (TPA_START_IS_IPV6(tpa_start1))
 			tpa_info->gso_type = SKB_GSO_TCPV6;
 		/* RSS profiles 1 and 3 with extract code 0 for inner 4-tuple */
-		else if (cmp_type == CMP_TYPE_RX_L2_TPA_START_CMP &&
+		else if (!BNXT_CHIP_P4_PLUS(bp) &&
 			 TPA_START_HASH_TYPE(tpa_start) == 3)
 			tpa_info->gso_type = SKB_GSO_TCPV6;
 		tpa_info->rss_hash =
@@ -2226,15 +2226,13 @@ static int bnxt_rx_pkt(struct bnxt *bp, struct bnxt_cp_ring_info *cpr,
 		if (cmp_type == CMP_TYPE_RX_L2_V3_CMP) {
 			type = bnxt_rss_ext_op(bp, rxcmp);
 		} else {
-			u32 hash_type = RX_CMP_HASH_TYPE(rxcmp);
+			u32 itypes = RX_CMP_ITYPES(rxcmp);
 
-			/* RSS profiles 1 and 3 with extract code 0 for inner
-			 * 4-tuple
-			 */
-			if (hash_type != 1 && hash_type != 3)
-				type = PKT_HASH_TYPE_L3;
-			else
+			if (itypes == RX_CMP_FLAGS_ITYPE_TCP ||
+			    itypes == RX_CMP_FLAGS_ITYPE_UDP)
 				type = PKT_HASH_TYPE_L4;
+			else
+				type = PKT_HASH_TYPE_L3;
 		}
 		skb_set_hash(skb, le32_to_cpu(rxcmp->rx_cmp_rss_hash), type);
 	}

drivers/net/ethernet/broadcom/bnxt/bnxt.h

@@ -267,6 +267,9 @@ struct rx_cmp {
 	(((le32_to_cpu((rxcmp)->rx_cmp_misc_v1) & RX_CMP_RSS_HASH_TYPE) >>\
 	  RX_CMP_RSS_HASH_TYPE_SHIFT) & RSS_PROFILE_ID_MASK)
 
+#define RX_CMP_ITYPES(rxcmp)					\
+	(le32_to_cpu((rxcmp)->rx_cmp_len_flags_type) & RX_CMP_FLAGS_ITYPES_MASK)
+
 #define RX_CMP_V3_HASH_TYPE_LEGACY(rxcmp)				\
 	((le32_to_cpu((rxcmp)->rx_cmp_misc_v1) & RX_CMP_V3_RSS_EXT_OP_LEGACY) >>\
 	 RX_CMP_V3_RSS_EXT_OP_LEGACY_SHIFT)