stmmac: change descriptor layout

This patch completely changes the descriptor layout to improve
the whole performances due to the single read usage of the
descriptors in critical paths.

Signed-off-by: Giuseppe Cavallaro <peppe.cavallaro@st.com>
Signed-off-by: Alexandre TORGUE <alexandre.torgue@st.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 70 insertions, 51 deletions

diff --git a/drivers/net/ethernet/stmicro/stmmac/norm_desc.c b/drivers/net/ethernet/stmicro/stmmac/norm_desc.c
index 48c3456445b2..460c573dd3e1 100644
--- a/drivers/net/ethernet/stmicro/stmmac/norm_desc.c
+++ b/drivers/net/ethernet/stmicro/stmmac/norm_desc.c
@@ -29,33 +29,38 @@
 static int ndesc_get_tx_status(void *data, struct stmmac_extra_stats *x,
 			       struct dma_desc *p, void __iomem *ioaddr)
 {
-	int ret = 0;
 	struct net_device_stats *stats = (struct net_device_stats *)data;
+	unsigned int tdes0 = p->des0;
+	int ret = 0;
 
-	if (unlikely(p->des01.tx.error_summary)) {
-		if (unlikely(p->des01.tx.underflow_error)) {
+	if (unlikely(tdes0 & TDES0_ERROR_SUMMARY)) {
+		if (unlikely(tdes0 & TDES0_UNDERFLOW_ERROR)) {
 			x->tx_underflow++;
 			stats->tx_fifo_errors++;
 		}
-		if (unlikely(p->des01.tx.no_carrier)) {
+		if (unlikely(tdes0 & TDES0_NO_CARRIER)) {
 			x->tx_carrier++;
 			stats->tx_carrier_errors++;
 		}
-		if (unlikely(p->des01.tx.loss_carrier)) {
+		if (unlikely(tdes0 & TDES0_LOSS_CARRIER)) {
 			x->tx_losscarrier++;
 			stats->tx_carrier_errors++;
 		}
-		if (unlikely((p->des01.tx.excessive_deferral) ||
-			     (p->des01.tx.excessive_collisions) ||
-			     (p->des01.tx.late_collision)))
-			stats->collisions += p->des01.tx.collision_count;
+		if (unlikely((tdes0 & TDES0_EXCESSIVE_DEFERRAL) ||
+			     (tdes0 & TDES0_EXCESSIVE_COLLISIONS) ||
+			     (tdes0 & TDES0_LATE_COLLISION))) {
+			unsigned int collisions;
+
+			collisions = (tdes0 & TDES0_COLLISION_COUNT_MASK) >> 3;
+			stats->collisions += collisions;
+		}
 		ret = -1;
 	}
 
-	if (p->des01.etx.vlan_frame)
+	if (tdes0 & TDES0_VLAN_FRAME)
 		x->tx_vlan++;
 
-	if (unlikely(p->des01.tx.deferred))
+	if (unlikely(tdes0 & TDES0_DEFERRED))
 		x->tx_deferred++;
 
 	return ret;
@@ -63,7 +68,7 @@ static int ndesc_get_tx_status(void *data, struct stmmac_extra_stats *x,
 
 static int ndesc_get_tx_len(struct dma_desc *p)
 {
-	return p->des01.tx.buffer1_size;
+	return (p->des1 & RDES1_BUFFER1_SIZE_MASK);
 }
 
 /* This function verifies if each incoming frame has some errors
@@ -74,47 +79,48 @@ static int ndesc_get_rx_status(void *data, struct stmmac_extra_stats *x,
 			       struct dma_desc *p)
 {
 	int ret = good_frame;
+	unsigned int rdes0 = p->des0;
 	struct net_device_stats *stats = (struct net_device_stats *)data;
 
-	if (unlikely(p->des01.rx.last_descriptor == 0)) {
+	if (unlikely(!(rdes0 & RDES0_LAST_DESCRIPTOR))) {
 		pr_warn("%s: Oversized frame spanned multiple buffers\n",
 			__func__);
 		stats->rx_length_errors++;
 		return discard_frame;
 	}
 
-	if (unlikely(p->des01.rx.error_summary)) {
-		if (unlikely(p->des01.rx.descriptor_error))
+	if (unlikely(rdes0 & RDES0_ERROR_SUMMARY)) {
+		if (unlikely(rdes0 & RDES0_DESCRIPTOR_ERROR))
 			x->rx_desc++;
-		if (unlikely(p->des01.rx.sa_filter_fail))
+		if (unlikely(rdes0 & RDES0_SA_FILTER_FAIL))
 			x->sa_filter_fail++;
-		if (unlikely(p->des01.rx.overflow_error))
+		if (unlikely(rdes0 & RDES0_OVERFLOW_ERROR))
 			x->overflow_error++;
-		if (unlikely(p->des01.rx.ipc_csum_error))
+		if (unlikely(rdes0 & RDES0_IPC_CSUM_ERROR))
 			x->ipc_csum_error++;
-		if (unlikely(p->des01.rx.collision)) {
+		if (unlikely(rdes0 & RDES0_COLLISION)) {
 			x->rx_collision++;
 			stats->collisions++;
 		}
-		if (unlikely(p->des01.rx.crc_error)) {
+		if (unlikely(rdes0 & RDES0_CRC_ERROR)) {
 			x->rx_crc++;
 			stats->rx_crc_errors++;
 		}
 		ret = discard_frame;
 	}
-	if (unlikely(p->des01.rx.dribbling))
+	if (unlikely(rdes0 & RDES0_DRIBBLING))
 		x->dribbling_bit++;
 
-	if (unlikely(p->des01.rx.length_error)) {
+	if (unlikely(rdes0 & RDES0_LENGTH_ERROR)) {
 		x->rx_length++;
 		ret = discard_frame;
 	}
-	if (unlikely(p->des01.rx.mii_error)) {
+	if (unlikely(rdes0 & RDES0_MII_ERROR)) {
 		x->rx_mii++;
 		ret = discard_frame;
 	}
 #ifdef STMMAC_VLAN_TAG_USED
-	if (p->des01.rx.vlan_tag)
+	if (rdes0 & RDES0_VLAN_TAG)
 		x->vlan_tag++;
 #endif
 	return ret;
@@ -123,9 +129,8 @@ static int ndesc_get_rx_status(void *data, struct stmmac_extra_stats *x,
 static void ndesc_init_rx_desc(struct dma_desc *p, int disable_rx_ic, int mode,
 			       int end)
 {
-	p->des01.all_flags = 0;
-	p->des01.rx.own = 1;
-	p->des01.rx.buffer1_size = BUF_SIZE_2KiB - 1;
+	p->des0 |= RDES0_OWN;
+	p->des1 |= (BUF_SIZE_2KiB - 1) & RDES1_BUFFER1_SIZE_MASK;
 
 	if (mode == STMMAC_CHAIN_MODE)
 		ndesc_rx_set_on_chain(p, end);
@@ -133,50 +138,50 @@ static void ndesc_init_rx_desc(struct dma_desc *p, int disable_rx_ic, int mode,
 		ndesc_rx_set_on_ring(p, end);
 
 	if (disable_rx_ic)
-		p->des01.rx.disable_ic = 1;
+		p->des1 |= RDES1_DISABLE_IC;
 }
 
 static void ndesc_init_tx_desc(struct dma_desc *p, int mode, int end)
 {
-	p->des01.all_flags = 0;
+	p->des0 &= ~TDES0_OWN;
 	if (mode == STMMAC_CHAIN_MODE)
-		ndesc_tx_set_on_chain(p, end);
+		ndesc_tx_set_on_chain(p);
 	else
-		ndesc_tx_set_on_ring(p, end);
+		ndesc_end_tx_desc_on_ring(p, end);
 }
 
 static int ndesc_get_tx_owner(struct dma_desc *p)
 {
-	return p->des01.tx.own;
+	return (p->des0 & TDES0_OWN) >> 31;
 }
 
 static int ndesc_get_rx_owner(struct dma_desc *p)
 {
-	return p->des01.rx.own;
+	return (p->des0 & RDES0_OWN) >> 31;
 }
 
 static void ndesc_set_tx_owner(struct dma_desc *p)
 {
-	p->des01.tx.own = 1;
+	p->des0 |= TDES0_OWN;
 }
 
 static void ndesc_set_rx_owner(struct dma_desc *p)
 {
-	p->des01.rx.own = 1;
+	p->des0 |= RDES0_OWN;
 }
 
 static int ndesc_get_tx_ls(struct dma_desc *p)
 {
-	return p->des01.tx.last_segment;
+	return (p->des1 & TDES1_LAST_SEGMENT) >> 30;
 }
 
 static void ndesc_release_tx_desc(struct dma_desc *p, int mode)
 {
-	int ter = p->des01.tx.end_ring;
+	int ter = (p->des1 & TDES1_END_RING) >> 25;
 
 	memset(p, 0, offsetof(struct dma_desc, des2));
 	if (mode == STMMAC_CHAIN_MODE)
-		ndesc_end_tx_desc_on_chain(p, ter);
+		ndesc_tx_set_on_chain(p);
 	else
 		ndesc_end_tx_desc_on_ring(p, ter);
 }
@@ -184,48 +189,62 @@ static void ndesc_release_tx_desc(struct dma_desc *p, int mode)
 static void ndesc_prepare_tx_desc(struct dma_desc *p, int is_fs, int len,
 				  int csum_flag, int mode)
 {
-	p->des01.tx.first_segment = is_fs;
+	unsigned int tdes1 = p->des1;
+
+	if (is_fs)
+		tdes1 |= TDES1_FIRST_SEGMENT;
+	else
+		tdes1 &= ~TDES1_FIRST_SEGMENT;
+
+	if (likely(csum_flag))
+		tdes1 |= (TX_CIC_FULL) << TDES1_CHECKSUM_INSERTION_SHIFT;
+	else
+		tdes1 &= ~(TX_CIC_FULL << TDES1_CHECKSUM_INSERTION_SHIFT);
+
+	p->des1 = tdes1;
+
 	if (mode == STMMAC_CHAIN_MODE)
 		norm_set_tx_desc_len_on_chain(p, len);
 	else
 		norm_set_tx_desc_len_on_ring(p, len);
-
-	if (likely(csum_flag))
-		p->des01.tx.checksum_insertion = cic_full;
 }
 
 static void ndesc_clear_tx_ic(struct dma_desc *p)
 {
-	p->des01.tx.interrupt = 0;
+	p->des1 &= ~TDES1_INTERRUPT;
 }
 
 static void ndesc_close_tx_desc(struct dma_desc *p)
 {
-	p->des01.tx.last_segment = 1;
-	p->des01.tx.interrupt = 1;
+	p->des1 |= TDES1_LAST_SEGMENT | TDES1_INTERRUPT;
 }
 
 static int ndesc_get_rx_frame_len(struct dma_desc *p, int rx_coe_type)
 {
+	unsigned int csum = 0;
+
 	/* The type-1 checksum offload engines append the checksum at
 	 * the end of frame and the two bytes of checksum are added in
 	 * the length.
 	 * Adjust for that in the framelen for type-1 checksum offload
-	 * engines. */
+	 * engines
+	 */
 	if (rx_coe_type == STMMAC_RX_COE_TYPE1)
-		return p->des01.rx.frame_length - 2;
-	else
-		return p->des01.rx.frame_length;
+		csum = 2;
+
+	return (((p->des0 & RDES0_FRAME_LEN_MASK) >> RDES0_FRAME_LEN_SHIFT) -
+		csum);
+
 }
 
 static void ndesc_enable_tx_timestamp(struct dma_desc *p)
 {
-	p->des01.tx.time_stamp_enable = 1;
+	p->des1 |= TDES1_TIME_STAMP_ENABLE;
 }
 
 static int ndesc_get_tx_timestamp_status(struct dma_desc *p)
 {
-	return p->des01.tx.time_stamp_status;
+	return (p->des0 & TDES0_TIME_STAMP_STATUS) >> 17;
 }
 
 static u64 ndesc_get_timestamp(void *desc, u32 ats)