stmmac: update normal descriptor structure (v2)

This patch updates the normal descriptor structure
to work fine on new GMAC Synopsys chips.

Normal descriptors were designed on the old MAC10/100
databook 1.91 where some bits were reserved: for example
the tx checksum insertion and rx checksum offload.

The patch maintains the back-compatibility with old
MAC devices (tested on STx7109 MAC10/100) and adds new
fields that actually new GMAC devices can use.

For example, STx7109 (MAC10/100) will pass from the platform
  tx_coe = 0, enh_desc = 0, has_gmac = 0.
A platform like Loongson1B (GMAC) will pass:
  tx_coe = 1, enh_desc = 0, has_gmac = 1.

Thanks to Kelvin, he enhanced the normal descriptors for
GMAC (on MIPS Loongson1B platform).

Signed-off-by: Kelvin Cheung <keguang.zhang@gmail.com>
Signed-off-by: Giuseppe Cavallaro <peppe.cavallaro@st.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

5 files changed, 51 insertions, 40 deletions

diff --git a/drivers/net/ethernet/stmicro/stmmac/common.h b/drivers/net/ethernet/stmicro/stmmac/common.h
index 9100c100d29..2cc11929582 100644
--- a/drivers/net/ethernet/stmicro/stmmac/common.h
+++ b/drivers/net/ethernet/stmicro/stmmac/common.h
@@ -49,7 +49,7 @@ struct stmmac_extra_stats {
         unsigned long tx_underflow ____cacheline_aligned;
         unsigned long tx_carrier;
         unsigned long tx_losscarrier;
-        unsigned long tx_heartbeat;
+        unsigned long vlan_tag;
         unsigned long tx_deferred;
         unsigned long tx_vlan;
         unsigned long tx_jabber;
@@ -58,9 +58,9 @@ struct stmmac_extra_stats {
         unsigned long tx_ip_header_error;
         /* Receive errors */
         unsigned long rx_desc;
-        unsigned long rx_partial;
-        unsigned long rx_runt;
-        unsigned long rx_toolong;
+        unsigned long sa_filter_fail;
+        unsigned long overflow_error;
+        unsigned long ipc_csum_error;
         unsigned long rx_collision;
         unsigned long rx_crc;
         unsigned long rx_length;
diff --git a/drivers/net/ethernet/stmicro/stmmac/descs.h b/drivers/net/ethernet/stmicro/stmmac/descs.h
index 63a03e26469..9820ec842cc 100644
--- a/drivers/net/ethernet/stmicro/stmmac/descs.h
+++ b/drivers/net/ethernet/stmicro/stmmac/descs.h
@@ -25,33 +25,34 @@ struct dma_desc {
         union {
                 struct {
                         /* RDES0 */
-                        u32 reserved1:1;
+                        u32 payload_csum_error:1;
                         u32 crc_error:1;
                         u32 dribbling:1;
                         u32 mii_error:1;
                         u32 receive_watchdog:1;
                         u32 frame_type:1;
                         u32 collision:1;
-                        u32 frame_too_long:1;
+                        u32 ipc_csum_error:1;
                         u32 last_descriptor:1;
                         u32 first_descriptor:1;
-                        u32 multicast_frame:1;
-                        u32 run_frame:1;
+                        u32 vlan_tag:1;
+                        u32 overflow_error:1;
                         u32 length_error:1;
-                        u32 partial_frame_error:1;
+                        u32 sa_filter_fail:1;
                         u32 descriptor_error:1;
                         u32 error_summary:1;
                         u32 frame_length:14;
-                        u32 filtering_fail:1;
+                        u32 da_filter_fail:1;
                         u32 own:1;
                         /* RDES1 */
                         u32 buffer1_size:11;
                         u32 buffer2_size:11;
-                        u32 reserved2:2;
+                        u32 reserved1:2;
                         u32 second_address_chained:1;
                         u32 end_ring:1;
-                        u32 reserved3:5;
+                        u32 reserved2:5;
                         u32 disable_ic:1;
+
                 } rx;
                 struct {
                         /* RDES0 */
@@ -91,24 +92,28 @@ struct dma_desc {
                         u32 underflow_error:1;
                         u32 excessive_deferral:1;
                         u32 collision_count:4;
-                        u32 heartbeat_fail:1;
+                        u32 vlan_frame:1;
                         u32 excessive_collisions:1;
                         u32 late_collision:1;
                         u32 no_carrier:1;
                         u32 loss_carrier:1;
-                        u32 reserved1:3;
+                        u32 payload_error:1;
+                        u32 frame_flushed:1;
+                        u32 jabber_timeout:1;
                         u32 error_summary:1;
-                        u32 reserved2:15;
+                        u32 ip_header_error:1;
+                        u32 time_stamp_status:1;
+                        u32 reserved1:13;
                         u32 own:1;
                         /* TDES1 */
                         u32 buffer1_size:11;
                         u32 buffer2_size:11;
-                        u32 reserved3:1;
+                        u32 time_stamp_enable:1;
                         u32 disable_padding:1;
                         u32 second_address_chained:1;
                         u32 end_ring:1;
                         u32 crc_disable:1;
-                        u32 reserved4:2;
+                        u32 checksum_insertion:2;
                         u32 first_segment:1;
                         u32 last_segment:1;
                         u32 interrupt:1;
diff --git a/drivers/net/ethernet/stmicro/stmmac/norm_desc.c b/drivers/net/ethernet/stmicro/stmmac/norm_desc.c
index f7e8ba7f501..fda5d2b31d3 100644
--- a/drivers/net/ethernet/stmicro/stmmac/norm_desc.c
+++ b/drivers/net/ethernet/stmicro/stmmac/norm_desc.c
@@ -50,11 +50,12 @@ static int ndesc_get_tx_status(void *data, struct stmmac_extra_stats *x,
                         stats->collisions += p->des01.tx.collision_count;
                 ret = -1;
         }
-        if (unlikely(p->des01.tx.heartbeat_fail)) {
-                x->tx_heartbeat++;
-                stats->tx_heartbeat_errors++;
-                ret = -1;
+
+        if (p->des01.etx.vlan_frame) {
+                CHIP_DBG(KERN_INFO "GMAC TX status: VLAN frame\n");
+                x->tx_vlan++;
         }
+
         if (unlikely(p->des01.tx.deferred))
                 x->tx_deferred++;
 
@@ -68,12 +69,12 @@ static int ndesc_get_tx_len(struct dma_desc *p)
 
 /* This function verifies if each incoming frame has some errors
  * and, if required, updates the multicast statistics.
- * In case of success, it returns csum_none because the device
- * is not able to compute the csum in HW. */
+ * In case of success, it returns good_frame because the GMAC device
+ * is supposed to be able to compute the csum in HW. */
 static int ndesc_get_rx_status(void *data, struct stmmac_extra_stats *x,
                                struct dma_desc *p)
 {
-        int ret = csum_none;
+        int ret = good_frame;
         struct net_device_stats *stats = (struct net_device_stats *)data;
 
         if (unlikely(p->des01.rx.last_descriptor == 0)) {
@@ -86,12 +87,12 @@ static int ndesc_get_rx_status(void *data, struct stmmac_extra_stats *x,
         if (unlikely(p->des01.rx.error_summary)) {
                 if (unlikely(p->des01.rx.descriptor_error))
                         x->rx_desc++;
-                if (unlikely(p->des01.rx.partial_frame_error))
-                        x->rx_partial++;
-                if (unlikely(p->des01.rx.run_frame))
-                        x->rx_runt++;
-                if (unlikely(p->des01.rx.frame_too_long))
-                        x->rx_toolong++;
+                if (unlikely(p->des01.rx.sa_filter_fail))
+                        x->sa_filter_fail++;
+                if (unlikely(p->des01.rx.overflow_error))
+                        x->overflow_error++;
+                if (unlikely(p->des01.rx.ipc_csum_error))
+                        x->ipc_csum_error++;
                 if (unlikely(p->des01.rx.collision)) {
                         x->rx_collision++;
                         stats->collisions++;
@@ -113,10 +114,10 @@ static int ndesc_get_rx_status(void *data, struct stmmac_extra_stats *x,
                 x->rx_mii++;
                 ret = discard_frame;
         }
-        if (p->des01.rx.multicast_frame) {
-                x->rx_multicast++;
-                stats->multicast++;
-        }
+#ifdef STMMAC_VLAN_TAG_USED
+        if (p->des01.rx.vlan_tag)
+                x->vlan_tag++;
+#endif
         return ret;
 }
 
@@ -184,6 +185,9 @@ static void ndesc_prepare_tx_desc(struct dma_desc *p, int is_fs, int len,
 {
         p->des01.tx.first_segment = is_fs;
         norm_set_tx_desc_len(p, len);
+
+        if (likely(csum_flag))
+                p->des01.tx.checksum_insertion = cic_full;
 }
 
 static void ndesc_clear_tx_ic(struct dma_desc *p)
diff --git a/drivers/net/ethernet/stmicro/stmmac/stmmac_ethtool.c b/drivers/net/ethernet/stmicro/stmmac/stmmac_ethtool.c
index 406404f6e32..e8eff09bbbd 100644
--- a/drivers/net/ethernet/stmicro/stmmac/stmmac_ethtool.c
+++ b/drivers/net/ethernet/stmicro/stmmac/stmmac_ethtool.c
@@ -50,7 +50,7 @@ static const struct stmmac_stats stmmac_gstrings_stats[] = {
         STMMAC_STAT(tx_underflow),
         STMMAC_STAT(tx_carrier),
         STMMAC_STAT(tx_losscarrier),
-        STMMAC_STAT(tx_heartbeat),
+        STMMAC_STAT(vlan_tag),
         STMMAC_STAT(tx_deferred),
         STMMAC_STAT(tx_vlan),
         STMMAC_STAT(rx_vlan),
@@ -59,9 +59,9 @@ static const struct stmmac_stats stmmac_gstrings_stats[] = {
         STMMAC_STAT(tx_payload_error),
         STMMAC_STAT(tx_ip_header_error),
         STMMAC_STAT(rx_desc),
-        STMMAC_STAT(rx_partial),
-        STMMAC_STAT(rx_runt),
-        STMMAC_STAT(rx_toolong),
+        STMMAC_STAT(sa_filter_fail),
+        STMMAC_STAT(overflow_error),
+        STMMAC_STAT(ipc_csum_error),
         STMMAC_STAT(rx_collision),
         STMMAC_STAT(rx_crc),
         STMMAC_STAT(rx_length),
diff --git a/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c b/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c
index 003ab56f49b..20546bbbb8d 100644
--- a/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c
+++ b/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c
@@ -813,6 +813,7 @@ static u32 stmmac_get_synopsys_id(struct stmmac_priv *priv)
 static int stmmac_get_hw_features(struct stmmac_priv *priv)
 {
         u32 hw_cap = 0;
+
         if (priv->hw->dma->get_hw_feature) {
                 hw_cap = priv->hw->dma->get_hw_feature(priv->ioaddr);
 
@@ -938,6 +939,7 @@ static int stmmac_open(struct net_device *dev)
 
         stmmac_get_hw_features(priv);
 
+        priv->rx_coe = priv->hw->mac->rx_coe(priv->ioaddr);
         if (priv->rx_coe)
                 pr_info("stmmac: Rx Checksum Offload Engine supported\n");
         if (priv->plat->tx_coe)
@@ -1275,8 +1277,8 @@ static int stmmac_rx(struct stmmac_priv *priv, int limit)
 #endif
                         skb->protocol = eth_type_trans(skb, priv->dev);
 
-                        if (unlikely(status == csum_none)) {
-                                /* always for the old mac 10/100 */
+                        if (unlikely(!priv->rx_coe)) {
+                                /* No RX COE for old mac10/100 devices */
                                 skb_checksum_none_assert(skb);
                                 netif_receive_skb(skb);
                         } else {