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, 34 insertions, 43 deletions

diff --git a/drivers/net/ethernet/stmicro/stmmac/descs_com.h b/drivers/net/ethernet/stmicro/stmmac/descs_com.h
index 6f2cc78c5cf5..7635a464ce41 100644
--- a/drivers/net/ethernet/stmicro/stmmac/descs_com.h
+++ b/drivers/net/ethernet/stmicro/stmmac/descs_com.h
@@ -35,100 +35,91 @@
 /* Enhanced descriptors */
 static inline void ehn_desc_rx_set_on_ring(struct dma_desc *p, int end)
 {
-	p->des01.erx.buffer2_size = BUF_SIZE_8KiB - 1;
-	if (end)
-		p->des01.erx.end_ring = 1;
-}
+	p->des1 |= ((BUF_SIZE_8KiB - 1) << ERDES1_BUFFER2_SIZE_SHIFT)
+		   & ERDES1_BUFFER2_SIZE_MASK;
 
-static inline void ehn_desc_tx_set_on_ring(struct dma_desc *p, int end)
-{
 	if (end)
-		p->des01.etx.end_ring = 1;
+		p->des1 |= ERDES1_END_RING;
 }
 
-static inline void enh_desc_end_tx_desc_on_ring(struct dma_desc *p, int ter)
+static inline void enh_desc_end_tx_desc_on_ring(struct dma_desc *p, int end)
 {
-	p->des01.etx.end_ring = ter;
+	if (end)
+		p->des0 |= ETDES0_END_RING;
+	else
+		p->des0 &= ~ETDES0_END_RING;
 }
 
 static inline void enh_set_tx_desc_len_on_ring(struct dma_desc *p, int len)
 {
 	if (unlikely(len > BUF_SIZE_4KiB)) {
-		p->des01.etx.buffer1_size = BUF_SIZE_4KiB;
-		p->des01.etx.buffer2_size = len - BUF_SIZE_4KiB;
+		p->des1 |= (((len - BUF_SIZE_4KiB) << ETDES1_BUFFER2_SIZE_SHIFT)
+			    & ETDES1_BUFFER2_SIZE_MASK) | (BUF_SIZE_4KiB
+			    & ETDES1_BUFFER1_SIZE_MASK);
 	} else
-		p->des01.etx.buffer1_size = len;
+		p->des1 |= (len & ETDES1_BUFFER1_SIZE_MASK);
 }
 
 /* Normal descriptors */
 static inline void ndesc_rx_set_on_ring(struct dma_desc *p, int end)
 {
-	p->des01.rx.buffer2_size = BUF_SIZE_2KiB - 1;
-	if (end)
-		p->des01.rx.end_ring = 1;
-}
+	p->des1 |= ((BUF_SIZE_2KiB - 1) << RDES1_BUFFER2_SIZE_SHIFT)
+		    & RDES1_BUFFER2_SIZE_MASK;
 
-static inline void ndesc_tx_set_on_ring(struct dma_desc *p, int end)
-{
 	if (end)
-		p->des01.tx.end_ring = 1;
+		p->des1 |= RDES1_END_RING;
 }
 
-static inline void ndesc_end_tx_desc_on_ring(struct dma_desc *p, int ter)
+static inline void ndesc_end_tx_desc_on_ring(struct dma_desc *p, int end)
 {
-	p->des01.tx.end_ring = ter;
+	if (end)
+		p->des1 |= TDES1_END_RING;
+	else
+		p->des1 &= ~TDES1_END_RING;
 }
 
 static inline void norm_set_tx_desc_len_on_ring(struct dma_desc *p, int len)
 {
 	if (unlikely(len > BUF_SIZE_2KiB)) {
-		p->des01.etx.buffer1_size = BUF_SIZE_2KiB - 1;
-		p->des01.etx.buffer2_size = len - p->des01.etx.buffer1_size;
+		unsigned int buffer1 = (BUF_SIZE_2KiB - 1)
+					& TDES1_BUFFER1_SIZE_MASK;
+		p->des1 |= ((((len - buffer1) << TDES1_BUFFER2_SIZE_SHIFT)
+			    & TDES1_BUFFER2_SIZE_MASK) | buffer1);
 	} else
-		p->des01.tx.buffer1_size = len;
+		p->des1 |= (len & TDES1_BUFFER1_SIZE_MASK);
 }
 
 /* Specific functions used for Chain mode */
 
 /* Enhanced descriptors */
-static inline void ehn_desc_rx_set_on_chain(struct dma_desc *p, int end)
-{
-	p->des01.erx.second_address_chained = 1;
-}
-
-static inline void ehn_desc_tx_set_on_chain(struct dma_desc *p, int end)
+static inline void ehn_desc_rx_set_on_chain(struct dma_desc *p)
 {
-	p->des01.etx.second_address_chained = 1;
+	p->des1 |= ERDES1_SECOND_ADDRESS_CHAINED;
 }
 
-static inline void enh_desc_end_tx_desc_on_chain(struct dma_desc *p, int ter)
+static inline void enh_desc_end_tx_desc_on_chain(struct dma_desc *p)
 {
-	p->des01.etx.second_address_chained = 1;
+	p->des0 |= ETDES0_SECOND_ADDRESS_CHAINED;
 }
 
 static inline void enh_set_tx_desc_len_on_chain(struct dma_desc *p, int len)
 {
-	p->des01.etx.buffer1_size = len;
+	p->des1 |= (len & ETDES1_BUFFER1_SIZE_MASK);
 }
 
 /* Normal descriptors */
 static inline void ndesc_rx_set_on_chain(struct dma_desc *p, int end)
 {
-	p->des01.rx.second_address_chained = 1;
-}
-
-static inline void ndesc_tx_set_on_chain(struct dma_desc *p, int ring_size)
-{
-	p->des01.tx.second_address_chained = 1;
+	p->des1 |= RDES1_SECOND_ADDRESS_CHAINED;
 }
 
-static inline void ndesc_end_tx_desc_on_chain(struct dma_desc *p, int ter)
+static inline void ndesc_tx_set_on_chain(struct dma_desc *p)
 {
-	p->des01.tx.second_address_chained = 1;
+	p->des1 |= TDES1_SECOND_ADDRESS_CHAINED;
 }
 
 static inline void norm_set_tx_desc_len_on_chain(struct dma_desc *p, int len)
 {
-	p->des01.tx.buffer1_size = len;
+	p->des1 |= len & TDES1_BUFFER1_SIZE_MASK;
 }
 #endif /* __DESC_COM_H__ */