[PATCH net-next v2 0/3] net: stmmac: Some improvements and a fix

[PATCH net-next v2 0/3] net: stmmac: Some improvements and a fix

[Jose Abreu]

Some performace improvements (01/03 and 03/03) and a fix (02/03), all for -next.

Cc: Joao Pinto <jpinto@synopsys.com>
Cc: David S. Miller <davem@davemloft.net>
Cc: Giuseppe Cavallaro <peppe.cavallaro@st.com>
Cc: Alexandre Torgue <alexandre.torgue@st.com>

Jose Abreu (3):
  net: stmmac: Implement RX Coalesce Frames setting
  net: stmmac: Fix descriptors address being in > 32 bits address space
  net: stmmac: Introducing support for Page Pool

 drivers/net/ethernet/stmicro/stmmac/Kconfig        |   1 +
 drivers/net/ethernet/stmicro/stmmac/common.h       |   1 +
 drivers/net/ethernet/stmicro/stmmac/dwmac-sun8i.c  |   8 +-
 .../net/ethernet/stmicro/stmmac/dwmac1000_dma.c    |   8 +-
 drivers/net/ethernet/stmicro/stmmac/dwmac100_dma.c |   8 +-
 drivers/net/ethernet/stmicro/stmmac/dwmac4_dma.c   |   8 +-
 drivers/net/ethernet/stmicro/stmmac/dwxgmac2.h     |   2 +
 drivers/net/ethernet/stmicro/stmmac/dwxgmac2_dma.c |  10 +-
 drivers/net/ethernet/stmicro/stmmac/hwif.h         |   4 +-
 drivers/net/ethernet/stmicro/stmmac/stmmac.h       |  12 +-
 .../net/ethernet/stmicro/stmmac/stmmac_ethtool.c   |   7 +-
 drivers/net/ethernet/stmicro/stmmac/stmmac_main.c  | 215 +++++++--------------
 12 files changed, 112 insertions(+), 172 deletions(-)

-- 
2.7.4

[PATCH net-next v2 1/3] net: stmmac: Implement RX Coalesce Frames setting

[Jose Abreu]

Add support for coalescing RX path by specifying number of frames which
don't need to have interrupt on completion bit set.

This is only available when RX Watchdog is enabled.

Acked-by: Jakub Kicinski <jakub.kicinski@netronome.com>
Signed-off-by: Jose Abreu <joabreu@synopsys.com>
Cc: Joao Pinto <jpinto@synopsys.com>
Cc: David S. Miller <davem@davemloft.net>
Cc: Giuseppe Cavallaro <peppe.cavallaro@st.com>
Cc: Alexandre Torgue <alexandre.torgue@st.com>
Cc: Jakub Kicinski <jakub.kicinski@netronome.com>
---
 drivers/net/ethernet/stmicro/stmmac/common.h         |  1 +
 drivers/net/ethernet/stmicro/stmmac/stmmac.h         |  2 ++
 drivers/net/ethernet/stmicro/stmmac/stmmac_ethtool.c |  7 +++++--
 drivers/net/ethernet/stmicro/stmmac/stmmac_main.c    | 18 ++++++++++++------
 4 files changed, 20 insertions(+), 8 deletions(-)

diff --git a/drivers/net/ethernet/stmicro/stmmac/common.h b/drivers/net/ethernet/stmicro/stmmac/common.h
index 2403a65167b2..dfd47fdfa447 100644
--- a/drivers/net/ethernet/stmicro/stmmac/common.h
+++ b/drivers/net/ethernet/stmicro/stmmac/common.h
@@ -252,6 +252,7 @@ struct stmmac_safety_stats {
 #define STMMAC_MAX_COAL_TX_TICK	100000
 #define STMMAC_TX_MAX_FRAMES	256
 #define STMMAC_TX_FRAMES	1
+#define STMMAC_RX_FRAMES	25
 
 /* Packets types */
 enum packets_types {
diff --git a/drivers/net/ethernet/stmicro/stmmac/stmmac.h b/drivers/net/ethernet/stmicro/stmmac/stmmac.h
index 123898235cb0..513f4e2df5f6 100644
--- a/drivers/net/ethernet/stmicro/stmmac/stmmac.h
+++ b/drivers/net/ethernet/stmicro/stmmac/stmmac.h
@@ -55,6 +55,7 @@ struct stmmac_tx_queue {
 };
 
 struct stmmac_rx_queue {
+	u32 rx_count_frames;
 	u32 queue_index;
 	struct stmmac_priv *priv_data;
 	struct dma_extended_desc *dma_erx;
@@ -110,6 +111,7 @@ struct stmmac_priv {
 	/* Frequently used values are kept adjacent for cache effect */
 	u32 tx_coal_frames;
 	u32 tx_coal_timer;
+	u32 rx_coal_frames;
 
 	int tx_coalesce;
 	int hwts_tx_en;
diff --git a/drivers/net/ethernet/stmicro/stmmac/stmmac_ethtool.c b/drivers/net/ethernet/stmicro/stmmac/stmmac_ethtool.c
index cfd93eefb50e..6efb66820d4c 100644
--- a/drivers/net/ethernet/stmicro/stmmac/stmmac_ethtool.c
+++ b/drivers/net/ethernet/stmicro/stmmac/stmmac_ethtool.c
@@ -701,8 +701,10 @@ static int stmmac_get_coalesce(struct net_device *dev,
 	ec->tx_coalesce_usecs = priv->tx_coal_timer;
 	ec->tx_max_coalesced_frames = priv->tx_coal_frames;
 
-	if (priv->use_riwt)
+	if (priv->use_riwt) {
+		ec->rx_max_coalesced_frames = priv->rx_coal_frames;
 		ec->rx_coalesce_usecs = stmmac_riwt2usec(priv->rx_riwt, priv);
+	}
 
 	return 0;
 }
@@ -715,7 +717,7 @@ static int stmmac_set_coalesce(struct net_device *dev,
 	unsigned int rx_riwt;
 
 	/* Check not supported parameters  */
-	if ((ec->rx_max_coalesced_frames) || (ec->rx_coalesce_usecs_irq) ||
+	if ((ec->rx_coalesce_usecs_irq) ||
 	    (ec->rx_max_coalesced_frames_irq) || (ec->tx_coalesce_usecs_irq) ||
 	    (ec->use_adaptive_rx_coalesce) || (ec->use_adaptive_tx_coalesce) ||
 	    (ec->pkt_rate_low) || (ec->rx_coalesce_usecs_low) ||
@@ -749,6 +751,7 @@ static int stmmac_set_coalesce(struct net_device *dev,
 	/* Only copy relevant parameters, ignore all others. */
 	priv->tx_coal_frames = ec->tx_max_coalesced_frames;
 	priv->tx_coal_timer = ec->tx_coalesce_usecs;
+	priv->rx_coal_frames = ec->rx_max_coalesced_frames;
 	priv->rx_riwt = rx_riwt;
 	stmmac_rx_watchdog(priv, priv->ioaddr, priv->rx_riwt, rx_cnt);
 
diff --git a/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c b/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c
index 3425d4dda03d..c8fe85ef9a7e 100644
--- a/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c
+++ b/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c
@@ -2268,20 +2268,21 @@ static void stmmac_tx_timer(struct timer_list *t)
 }
 
 /**
- * stmmac_init_tx_coalesce - init tx mitigation options.
+ * stmmac_init_coalesce - init mitigation options.
  * @priv: driver private structure
  * Description:
- * This inits the transmit coalesce parameters: i.e. timer rate,
+ * This inits the coalesce parameters: i.e. timer rate,
  * timer handler and default threshold used for enabling the
  * interrupt on completion bit.
  */
-static void stmmac_init_tx_coalesce(struct stmmac_priv *priv)
+static void stmmac_init_coalesce(struct stmmac_priv *priv)
 {
 	u32 tx_channel_count = priv->plat->tx_queues_to_use;
 	u32 chan;
 
 	priv->tx_coal_frames = STMMAC_TX_FRAMES;
 	priv->tx_coal_timer = STMMAC_COAL_TX_TIMER;
+	priv->rx_coal_frames = STMMAC_RX_FRAMES;
 
 	for (chan = 0; chan < tx_channel_count; chan++) {
 		struct stmmac_tx_queue *tx_q = &priv->tx_queue[chan];
@@ -2651,7 +2652,7 @@ static int stmmac_open(struct net_device *dev)
 		goto init_error;
 	}
 
-	stmmac_init_tx_coalesce(priv);
+	stmmac_init_coalesce(priv);
 
 	phylink_start(priv->phylink);
 
@@ -3298,6 +3299,7 @@ static inline void stmmac_rx_refill(struct stmmac_priv *priv, u32 queue)
 
 	while (dirty-- > 0) {
 		struct dma_desc *p;
+		bool use_rx_wd;
 
 		if (priv->extend_desc)
 			p = (struct dma_desc *)(rx_q->dma_erx + entry);
@@ -3340,7 +3342,11 @@ static inline void stmmac_rx_refill(struct stmmac_priv *priv, u32 queue)
 		}
 		dma_wmb();
 
-		stmmac_set_rx_owner(priv, p, priv->use_riwt);
+		rx_q->rx_count_frames++;
+		rx_q->rx_count_frames %= priv->rx_coal_frames;
+		use_rx_wd = priv->use_riwt && rx_q->rx_count_frames;
+
+		stmmac_set_rx_owner(priv, p, use_rx_wd);
 
 		dma_wmb();
 
@@ -4623,7 +4629,7 @@ int stmmac_resume(struct device *dev)
 	stmmac_clear_descriptors(priv);
 
 	stmmac_hw_setup(ndev, false);
-	stmmac_init_tx_coalesce(priv);
+	stmmac_init_coalesce(priv);
 	stmmac_set_rx_mode(ndev);
 
 	stmmac_enable_all_queues(priv);
-- 
2.7.4

[PATCH net-next v2 2/3] net: stmmac: Fix descriptors address being in > 32 bits address space

[Jose Abreu]

Commit a993db88d17d ("net: stmmac: Enable support for > 32 Bits
addressing in XGMAC"), introduced support for > 32 bits addressing in
XGMAC but the conversion of descriptors to dma_addr_t was left out.

As some devices assing coherent memory in regions > 32 bits we need to
set lower and upper value of descriptors address when initializing DMA
channels.

Luckly, this was working for me because I was assigning CMA to < 4GB
address space for performance reasons.

Fixes: a993db88d17d ("net: stmmac: Enable support for > 32 Bits addressing in XGMAC")
Signed-off-by: Jose Abreu <joabreu@synopsys.com>
Cc: Joao Pinto <jpinto@synopsys.com>
Cc: David S. Miller <davem@davemloft.net>
Cc: Giuseppe Cavallaro <peppe.cavallaro@st.com>
Cc: Alexandre Torgue <alexandre.torgue@st.com>
Cc: Maxime Coquelin <mcoquelin.stm32@gmail.com>
Cc: Maxime Ripard <maxime.ripard@bootlin.com>
Cc: Chen-Yu Tsai <wens@csie.org>
---
 drivers/net/ethernet/stmicro/stmmac/dwmac-sun8i.c   |  8 ++++----
 drivers/net/ethernet/stmicro/stmmac/dwmac1000_dma.c |  8 ++++----
 drivers/net/ethernet/stmicro/stmmac/dwmac100_dma.c  |  8 ++++----
 drivers/net/ethernet/stmicro/stmmac/dwmac4_dma.c    |  8 ++++----
 drivers/net/ethernet/stmicro/stmmac/dwxgmac2.h      |  2 ++
 drivers/net/ethernet/stmicro/stmmac/dwxgmac2_dma.c  | 10 ++++++----
 drivers/net/ethernet/stmicro/stmmac/hwif.h          |  4 ++--
 7 files changed, 26 insertions(+), 22 deletions(-)

diff --git a/drivers/net/ethernet/stmicro/stmmac/dwmac-sun8i.c b/drivers/net/ethernet/stmicro/stmmac/dwmac-sun8i.c
index 6d5cba4075eb..2856f3fe5266 100644
--- a/drivers/net/ethernet/stmicro/stmmac/dwmac-sun8i.c
+++ b/drivers/net/ethernet/stmicro/stmmac/dwmac-sun8i.c
@@ -289,18 +289,18 @@ static void sun8i_dwmac_dma_init(void __iomem *ioaddr,
 
 static void sun8i_dwmac_dma_init_rx(void __iomem *ioaddr,
 				    struct stmmac_dma_cfg *dma_cfg,
-				    u32 dma_rx_phy, u32 chan)
+				    dma_addr_t dma_rx_phy, u32 chan)
 {
 	/* Write RX descriptors address */
-	writel(dma_rx_phy, ioaddr + EMAC_RX_DESC_LIST);
+	writel(lower_32_bits(dma_rx_phy), ioaddr + EMAC_RX_DESC_LIST);
 }
 
 static void sun8i_dwmac_dma_init_tx(void __iomem *ioaddr,
 				    struct stmmac_dma_cfg *dma_cfg,
-				    u32 dma_tx_phy, u32 chan)
+				    dma_addr_t dma_tx_phy, u32 chan)
 {
 	/* Write TX descriptors address */
-	writel(dma_tx_phy, ioaddr + EMAC_TX_DESC_LIST);
+	writel(lower_32_bits(dma_tx_phy), ioaddr + EMAC_TX_DESC_LIST);
 }
 
 /* sun8i_dwmac_dump_regs() - Dump EMAC address space
diff --git a/drivers/net/ethernet/stmicro/stmmac/dwmac1000_dma.c b/drivers/net/ethernet/stmicro/stmmac/dwmac1000_dma.c
index 1fdedf77678f..2bac49b49f73 100644
--- a/drivers/net/ethernet/stmicro/stmmac/dwmac1000_dma.c
+++ b/drivers/net/ethernet/stmicro/stmmac/dwmac1000_dma.c
@@ -112,18 +112,18 @@ static void dwmac1000_dma_init(void __iomem *ioaddr,
 
 static void dwmac1000_dma_init_rx(void __iomem *ioaddr,
 				  struct stmmac_dma_cfg *dma_cfg,
-				  u32 dma_rx_phy, u32 chan)
+				  dma_addr_t dma_rx_phy, u32 chan)
 {
 	/* RX descriptor base address list must be written into DMA CSR3 */
-	writel(dma_rx_phy, ioaddr + DMA_RCV_BASE_ADDR);
+	writel(lower_32_bits(dma_rx_phy), ioaddr + DMA_RCV_BASE_ADDR);
 }
 
 static void dwmac1000_dma_init_tx(void __iomem *ioaddr,
 				  struct stmmac_dma_cfg *dma_cfg,
-				  u32 dma_tx_phy, u32 chan)
+				  dma_addr_t dma_tx_phy, u32 chan)
 {
 	/* TX descriptor base address list must be written into DMA CSR4 */
-	writel(dma_tx_phy, ioaddr + DMA_TX_BASE_ADDR);
+	writel(lower_32_bits(dma_tx_phy), ioaddr + DMA_TX_BASE_ADDR);
 }
 
 static u32 dwmac1000_configure_fc(u32 csr6, int rxfifosz)
diff --git a/drivers/net/ethernet/stmicro/stmmac/dwmac100_dma.c b/drivers/net/ethernet/stmicro/stmmac/dwmac100_dma.c
index c980cc7360a4..8f0d9bc7cab5 100644
--- a/drivers/net/ethernet/stmicro/stmmac/dwmac100_dma.c
+++ b/drivers/net/ethernet/stmicro/stmmac/dwmac100_dma.c
@@ -31,18 +31,18 @@ static void dwmac100_dma_init(void __iomem *ioaddr,
 
 static void dwmac100_dma_init_rx(void __iomem *ioaddr,
 				 struct stmmac_dma_cfg *dma_cfg,
-				 u32 dma_rx_phy, u32 chan)
+				 dma_addr_t dma_rx_phy, u32 chan)
 {
 	/* RX descriptor base addr lists must be written into DMA CSR3 */
-	writel(dma_rx_phy, ioaddr + DMA_RCV_BASE_ADDR);
+	writel(lower_32_bits(dma_rx_phy), ioaddr + DMA_RCV_BASE_ADDR);
 }
 
 static void dwmac100_dma_init_tx(void __iomem *ioaddr,
 				 struct stmmac_dma_cfg *dma_cfg,
-				 u32 dma_tx_phy, u32 chan)
+				 dma_addr_t dma_tx_phy, u32 chan)
 {
 	/* TX descriptor base addr lists must be written into DMA CSR4 */
-	writel(dma_tx_phy, ioaddr + DMA_TX_BASE_ADDR);
+	writel(lower_32_bits(dma_tx_phy), ioaddr + DMA_TX_BASE_ADDR);
 }
 
 /* Store and Forward capability is not used at all.
diff --git a/drivers/net/ethernet/stmicro/stmmac/dwmac4_dma.c b/drivers/net/ethernet/stmicro/stmmac/dwmac4_dma.c
index 0f208e13da9f..6cbcdaea55f6 100644
--- a/drivers/net/ethernet/stmicro/stmmac/dwmac4_dma.c
+++ b/drivers/net/ethernet/stmicro/stmmac/dwmac4_dma.c
@@ -70,7 +70,7 @@ static void dwmac4_dma_axi(void __iomem *ioaddr, struct stmmac_axi *axi)
 
 static void dwmac4_dma_init_rx_chan(void __iomem *ioaddr,
 				    struct stmmac_dma_cfg *dma_cfg,
-				    u32 dma_rx_phy, u32 chan)
+				    dma_addr_t dma_rx_phy, u32 chan)
 {
 	u32 value;
 	u32 rxpbl = dma_cfg->rxpbl ?: dma_cfg->pbl;
@@ -79,12 +79,12 @@ static void dwmac4_dma_init_rx_chan(void __iomem *ioaddr,
 	value = value | (rxpbl << DMA_BUS_MODE_RPBL_SHIFT);
 	writel(value, ioaddr + DMA_CHAN_RX_CONTROL(chan));
 
-	writel(dma_rx_phy, ioaddr + DMA_CHAN_RX_BASE_ADDR(chan));
+	writel(lower_32_bits(dma_rx_phy), ioaddr + DMA_CHAN_RX_BASE_ADDR(chan));
 }
 
 static void dwmac4_dma_init_tx_chan(void __iomem *ioaddr,
 				    struct stmmac_dma_cfg *dma_cfg,
-				    u32 dma_tx_phy, u32 chan)
+				    dma_addr_t dma_tx_phy, u32 chan)
 {
 	u32 value;
 	u32 txpbl = dma_cfg->txpbl ?: dma_cfg->pbl;
@@ -97,7 +97,7 @@ static void dwmac4_dma_init_tx_chan(void __iomem *ioaddr,
 
 	writel(value, ioaddr + DMA_CHAN_TX_CONTROL(chan));
 
-	writel(dma_tx_phy, ioaddr + DMA_CHAN_TX_BASE_ADDR(chan));
+	writel(lower_32_bits(dma_tx_phy), ioaddr + DMA_CHAN_TX_BASE_ADDR(chan));
 }
 
 static void dwmac4_dma_init_channel(void __iomem *ioaddr,
diff --git a/drivers/net/ethernet/stmicro/stmmac/dwxgmac2.h b/drivers/net/ethernet/stmicro/stmmac/dwxgmac2.h
index 9a9792527530..7f86dffb264d 100644
--- a/drivers/net/ethernet/stmicro/stmmac/dwxgmac2.h
+++ b/drivers/net/ethernet/stmicro/stmmac/dwxgmac2.h
@@ -199,7 +199,9 @@
 #define XGMAC_RxPBL			GENMASK(21, 16)
 #define XGMAC_RxPBL_SHIFT		16
 #define XGMAC_RXST			BIT(0)
+#define XGMAC_DMA_CH_TxDESC_HADDR(x)	(0x00003110 + (0x80 * (x)))
 #define XGMAC_DMA_CH_TxDESC_LADDR(x)	(0x00003114 + (0x80 * (x)))
+#define XGMAC_DMA_CH_RxDESC_HADDR(x)	(0x00003118 + (0x80 * (x)))
 #define XGMAC_DMA_CH_RxDESC_LADDR(x)	(0x0000311c + (0x80 * (x)))
 #define XGMAC_DMA_CH_TxDESC_TAIL_LPTR(x)	(0x00003124 + (0x80 * (x)))
 #define XGMAC_DMA_CH_RxDESC_TAIL_LPTR(x)	(0x0000312c + (0x80 * (x)))
diff --git a/drivers/net/ethernet/stmicro/stmmac/dwxgmac2_dma.c b/drivers/net/ethernet/stmicro/stmmac/dwxgmac2_dma.c
index 229c58758cbd..a4f236e3593e 100644
--- a/drivers/net/ethernet/stmicro/stmmac/dwxgmac2_dma.c
+++ b/drivers/net/ethernet/stmicro/stmmac/dwxgmac2_dma.c
@@ -44,7 +44,7 @@ static void dwxgmac2_dma_init_chan(void __iomem *ioaddr,
 
 static void dwxgmac2_dma_init_rx_chan(void __iomem *ioaddr,
 				      struct stmmac_dma_cfg *dma_cfg,
-				      u32 dma_rx_phy, u32 chan)
+				      dma_addr_t phy, u32 chan)
 {
 	u32 rxpbl = dma_cfg->rxpbl ?: dma_cfg->pbl;
 	u32 value;
@@ -54,12 +54,13 @@ static void dwxgmac2_dma_init_rx_chan(void __iomem *ioaddr,
 	value |= (rxpbl << XGMAC_RxPBL_SHIFT) & XGMAC_RxPBL;
 	writel(value, ioaddr + XGMAC_DMA_CH_RX_CONTROL(chan));
 
-	writel(dma_rx_phy, ioaddr + XGMAC_DMA_CH_RxDESC_LADDR(chan));
+	writel(upper_32_bits(phy), ioaddr + XGMAC_DMA_CH_RxDESC_HADDR(chan));
+	writel(lower_32_bits(phy), ioaddr + XGMAC_DMA_CH_RxDESC_LADDR(chan));
 }
 
 static void dwxgmac2_dma_init_tx_chan(void __iomem *ioaddr,
 				      struct stmmac_dma_cfg *dma_cfg,
-				      u32 dma_tx_phy, u32 chan)
+				      dma_addr_t phy, u32 chan)
 {
 	u32 txpbl = dma_cfg->txpbl ?: dma_cfg->pbl;
 	u32 value;
@@ -70,7 +71,8 @@ static void dwxgmac2_dma_init_tx_chan(void __iomem *ioaddr,
 	value |= XGMAC_OSP;
 	writel(value, ioaddr + XGMAC_DMA_CH_TX_CONTROL(chan));
 
-	writel(dma_tx_phy, ioaddr + XGMAC_DMA_CH_TxDESC_LADDR(chan));
+	writel(upper_32_bits(phy), ioaddr + XGMAC_DMA_CH_TxDESC_HADDR(chan));
+	writel(lower_32_bits(phy), ioaddr + XGMAC_DMA_CH_TxDESC_LADDR(chan));
 }
 
 static void dwxgmac2_dma_axi(void __iomem *ioaddr, struct stmmac_axi *axi)
diff --git a/drivers/net/ethernet/stmicro/stmmac/hwif.h b/drivers/net/ethernet/stmicro/stmmac/hwif.h
index 2acfbc70e3c8..278c0dbec9d9 100644
--- a/drivers/net/ethernet/stmicro/stmmac/hwif.h
+++ b/drivers/net/ethernet/stmicro/stmmac/hwif.h
@@ -150,10 +150,10 @@ struct stmmac_dma_ops {
 			  struct stmmac_dma_cfg *dma_cfg, u32 chan);
 	void (*init_rx_chan)(void __iomem *ioaddr,
 			     struct stmmac_dma_cfg *dma_cfg,
-			     u32 dma_rx_phy, u32 chan);
+			     dma_addr_t phy, u32 chan);
 	void (*init_tx_chan)(void __iomem *ioaddr,
 			     struct stmmac_dma_cfg *dma_cfg,
-			     u32 dma_tx_phy, u32 chan);
+			     dma_addr_t phy, u32 chan);
 	/* Configure the AXI Bus Mode Register */
 	void (*axi)(void __iomem *ioaddr, struct stmmac_axi *axi);
 	/* Dump DMA registers */
-- 
2.7.4

[PATCH net-next v2 3/3] net: stmmac: Introducing support for Page Pool

[Jose Abreu]

Mapping and unmapping DMA region is an high bottleneck in stmmac driver,
specially in the RX path.

This commit introduces support for Page Pool API and uses it in all RX
queues. With this change, we get more stable troughput and some increase
of banwidth with iperf:
	- MAC1000 - 950 Mbps
	- XGMAC: 9.22 Gbps

Changes from v1:
	- Use page_pool_get_dma_addr() (Jesper)
	- Add a comment (Jesper)
	- Add page_pool_free() call (Jesper)
	- Reintroduce sync_single_for_device (Arnd / Ilias)

Signed-off-by: Jose Abreu <joabreu@synopsys.com>
Cc: Joao Pinto <jpinto@synopsys.com>
Cc: David S. Miller <davem@davemloft.net>
Cc: Giuseppe Cavallaro <peppe.cavallaro@st.com>
Cc: Alexandre Torgue <alexandre.torgue@st.com>
Cc: Ilias Apalodimas <ilias.apalodimas@linaro.org>
Cc: Jesper Dangaard Brouer <brouer@redhat.com>
Cc: Arnd Bergmann <arnd@arndb.de>
---
 drivers/net/ethernet/stmicro/stmmac/Kconfig       |   1 +
 drivers/net/ethernet/stmicro/stmmac/stmmac.h      |  10 +-
 drivers/net/ethernet/stmicro/stmmac/stmmac_main.c | 201 +++++++---------------
 3 files changed, 68 insertions(+), 144 deletions(-)

diff --git a/drivers/net/ethernet/stmicro/stmmac/Kconfig b/drivers/net/ethernet/stmicro/stmmac/Kconfig
index 943189dcccb1..2325b40dff6e 100644
--- a/drivers/net/ethernet/stmicro/stmmac/Kconfig
+++ b/drivers/net/ethernet/stmicro/stmmac/Kconfig
@@ -3,6 +3,7 @@ config STMMAC_ETH
 	tristate "STMicroelectronics Multi-Gigabit Ethernet driver"
 	depends on HAS_IOMEM && HAS_DMA
 	select MII
+	select PAGE_POOL
 	select PHYLINK
 	select CRC32
 	imply PTP_1588_CLOCK
diff --git a/drivers/net/ethernet/stmicro/stmmac/stmmac.h b/drivers/net/ethernet/stmicro/stmmac/stmmac.h
index 513f4e2df5f6..5cd966c154f3 100644
--- a/drivers/net/ethernet/stmicro/stmmac/stmmac.h
+++ b/drivers/net/ethernet/stmicro/stmmac/stmmac.h
@@ -20,6 +20,7 @@
 #include <linux/ptp_clock_kernel.h>
 #include <linux/net_tstamp.h>
 #include <linux/reset.h>
+#include <net/page_pool.h>
 
 struct stmmac_resources {
 	void __iomem *addr;
@@ -54,14 +55,19 @@ struct stmmac_tx_queue {
 	u32 mss;
 };
 
+struct stmmac_rx_buffer {
+	struct page *page;
+	dma_addr_t addr;
+};
+
 struct stmmac_rx_queue {
 	u32 rx_count_frames;
 	u32 queue_index;
+	struct page_pool *page_pool;
+	struct stmmac_rx_buffer *buf_pool;
 	struct stmmac_priv *priv_data;
 	struct dma_extended_desc *dma_erx;
 	struct dma_desc *dma_rx ____cacheline_aligned_in_smp;
-	struct sk_buff **rx_skbuff;
-	dma_addr_t *rx_skbuff_dma;
 	unsigned int cur_rx;
 	unsigned int dirty_rx;
 	u32 rx_zeroc_thresh;
diff --git a/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c b/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c
index c8fe85ef9a7e..ec7ae81b65cc 100644
--- a/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c
+++ b/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c
@@ -1197,26 +1197,14 @@ static int stmmac_init_rx_buffers(struct stmmac_priv *priv, struct dma_desc *p,
 				  int i, gfp_t flags, u32 queue)
 {
 	struct stmmac_rx_queue *rx_q = &priv->rx_queue[queue];
-	struct sk_buff *skb;
+	struct stmmac_rx_buffer *buf = &rx_q->buf_pool[i];
 
-	skb = __netdev_alloc_skb_ip_align(priv->dev, priv->dma_buf_sz, flags);
-	if (!skb) {
-		netdev_err(priv->dev,
-			   "%s: Rx init fails; skb is NULL\n", __func__);
+	buf->page = page_pool_dev_alloc_pages(rx_q->page_pool);
+	if (!buf->page)
 		return -ENOMEM;
-	}
-	rx_q->rx_skbuff[i] = skb;
-	rx_q->rx_skbuff_dma[i] = dma_map_single(priv->device, skb->data,
-						priv->dma_buf_sz,
-						DMA_FROM_DEVICE);
-	if (dma_mapping_error(priv->device, rx_q->rx_skbuff_dma[i])) {
-		netdev_err(priv->dev, "%s: DMA mapping error\n", __func__);
-		dev_kfree_skb_any(skb);
-		return -EINVAL;
-	}
-
-	stmmac_set_desc_addr(priv, p, rx_q->rx_skbuff_dma[i]);
 
+	buf->addr = page_pool_get_dma_addr(buf->page);
+	stmmac_set_desc_addr(priv, p, buf->addr);
 	if (priv->dma_buf_sz == BUF_SIZE_16KiB)
 		stmmac_init_desc3(priv, p);
 
@@ -1232,13 +1220,11 @@ static int stmmac_init_rx_buffers(struct stmmac_priv *priv, struct dma_desc *p,
 static void stmmac_free_rx_buffer(struct stmmac_priv *priv, u32 queue, int i)
 {
 	struct stmmac_rx_queue *rx_q = &priv->rx_queue[queue];
+	struct stmmac_rx_buffer *buf = &rx_q->buf_pool[i];
 
-	if (rx_q->rx_skbuff[i]) {
-		dma_unmap_single(priv->device, rx_q->rx_skbuff_dma[i],
-				 priv->dma_buf_sz, DMA_FROM_DEVICE);
-		dev_kfree_skb_any(rx_q->rx_skbuff[i]);
-	}
-	rx_q->rx_skbuff[i] = NULL;
+	if (buf->page)
+		page_pool_put_page(rx_q->page_pool, buf->page, false);
+	buf->page = NULL;
 }
 
 /**
@@ -1321,10 +1307,6 @@ static int init_dma_rx_desc_rings(struct net_device *dev, gfp_t flags)
 						     queue);
 			if (ret)
 				goto err_init_rx_buffers;
-
-			netif_dbg(priv, probe, priv->dev, "[%p]\t[%p]\t[%x]\n",
-				  rx_q->rx_skbuff[i], rx_q->rx_skbuff[i]->data,
-				  (unsigned int)rx_q->rx_skbuff_dma[i]);
 		}
 
 		rx_q->cur_rx = 0;
@@ -1498,8 +1480,9 @@ static void free_dma_rx_desc_resources(struct stmmac_priv *priv)
 					  sizeof(struct dma_extended_desc),
 					  rx_q->dma_erx, rx_q->dma_rx_phy);
 
-		kfree(rx_q->rx_skbuff_dma);
-		kfree(rx_q->rx_skbuff);
+		kfree(rx_q->buf_pool);
+		if (rx_q->page_pool && page_pool_request_shutdown(rx_q->page_pool))
+			page_pool_free(rx_q->page_pool);
 	}
 }
 
@@ -1551,20 +1534,29 @@ static int alloc_dma_rx_desc_resources(struct stmmac_priv *priv)
 	/* RX queues buffers and DMA */
 	for (queue = 0; queue < rx_count; queue++) {
 		struct stmmac_rx_queue *rx_q = &priv->rx_queue[queue];
+		struct page_pool_params pp_params = { 0 };
 
 		rx_q->queue_index = queue;
 		rx_q->priv_data = priv;
 
-		rx_q->rx_skbuff_dma = kmalloc_array(DMA_RX_SIZE,
-						    sizeof(dma_addr_t),
-						    GFP_KERNEL);
-		if (!rx_q->rx_skbuff_dma)
+		pp_params.flags = PP_FLAG_DMA_MAP;
+		pp_params.pool_size = DMA_RX_SIZE;
+		pp_params.order = DIV_ROUND_UP(priv->dma_buf_sz, PAGE_SIZE);
+		pp_params.nid = dev_to_node(priv->device);
+		pp_params.dev = priv->device;
+		pp_params.dma_dir = DMA_FROM_DEVICE;
+
+		rx_q->page_pool = page_pool_create(&pp_params);
+		if (IS_ERR(rx_q->page_pool)) {
+			ret = PTR_ERR(rx_q->page_pool);
+			rx_q->page_pool = NULL;
 			goto err_dma;
+		}
 
-		rx_q->rx_skbuff = kmalloc_array(DMA_RX_SIZE,
-						sizeof(struct sk_buff *),
-						GFP_KERNEL);
-		if (!rx_q->rx_skbuff)
+		rx_q->buf_pool = kmalloc_array(DMA_RX_SIZE,
+					       sizeof(*rx_q->buf_pool),
+					       GFP_KERNEL);
+		if (!rx_q->buf_pool)
 			goto err_dma;
 
 		if (priv->extend_desc) {
@@ -3295,9 +3287,8 @@ static inline void stmmac_rx_refill(struct stmmac_priv *priv, u32 queue)
 	int dirty = stmmac_rx_dirty(priv, queue);
 	unsigned int entry = rx_q->dirty_rx;
 
-	int bfsize = priv->dma_buf_sz;
-
 	while (dirty-- > 0) {
+		struct stmmac_rx_buffer *buf = &rx_q->buf_pool[entry];
 		struct dma_desc *p;
 		bool use_rx_wd;
 
@@ -3306,49 +3297,22 @@ static inline void stmmac_rx_refill(struct stmmac_priv *priv, u32 queue)
 		else
 			p = rx_q->dma_rx + entry;
 
-		if (likely(!rx_q->rx_skbuff[entry])) {
-			struct sk_buff *skb;
-
-			skb = netdev_alloc_skb_ip_align(priv->dev, bfsize);
-			if (unlikely(!skb)) {
-				/* so for a while no zero-copy! */
-				rx_q->rx_zeroc_thresh = STMMAC_RX_THRESH;
-				if (unlikely(net_ratelimit()))
-					dev_err(priv->device,
-						"fail to alloc skb entry %d\n",
-						entry);
-				break;
-			}
-
-			rx_q->rx_skbuff[entry] = skb;
-			rx_q->rx_skbuff_dma[entry] =
-			    dma_map_single(priv->device, skb->data, bfsize,
-					   DMA_FROM_DEVICE);
-			if (dma_mapping_error(priv->device,
-					      rx_q->rx_skbuff_dma[entry])) {
-				netdev_err(priv->dev, "Rx DMA map failed\n");
-				dev_kfree_skb(skb);
+		if (!buf->page) {
+			buf->page = page_pool_dev_alloc_pages(rx_q->page_pool);
+			if (!buf->page)
 				break;
-			}
-
-			stmmac_set_desc_addr(priv, p, rx_q->rx_skbuff_dma[entry]);
-			stmmac_refill_desc3(priv, rx_q, p);
-
-			if (rx_q->rx_zeroc_thresh > 0)
-				rx_q->rx_zeroc_thresh--;
-
-			netif_dbg(priv, rx_status, priv->dev,
-				  "refill entry #%d\n", entry);
 		}
-		dma_wmb();
+
+		buf->addr = page_pool_get_dma_addr(buf->page);
+		stmmac_set_desc_addr(priv, p, buf->addr);
+		stmmac_refill_desc3(priv, rx_q, p);
 
 		rx_q->rx_count_frames++;
 		rx_q->rx_count_frames %= priv->rx_coal_frames;
 		use_rx_wd = priv->use_riwt && rx_q->rx_count_frames;
 
-		stmmac_set_rx_owner(priv, p, use_rx_wd);
-
 		dma_wmb();
+		stmmac_set_rx_owner(priv, p, use_rx_wd);
 
 		entry = STMMAC_GET_ENTRY(entry, DMA_RX_SIZE);
 	}
@@ -3373,9 +3337,6 @@ static int stmmac_rx(struct stmmac_priv *priv, int limit, u32 queue)
 	unsigned int next_entry = rx_q->cur_rx;
 	int coe = priv->hw->rx_csum;
 	unsigned int count = 0;
-	bool xmac;
-
-	xmac = priv->plat->has_gmac4 || priv->plat->has_xgmac;
 
 	if (netif_msg_rx_status(priv)) {
 		void *rx_head;
@@ -3389,11 +3350,12 @@ static int stmmac_rx(struct stmmac_priv *priv, int limit, u32 queue)
 		stmmac_display_ring(priv, rx_head, DMA_RX_SIZE, true);
 	}
 	while (count < limit) {
+		struct stmmac_rx_buffer *buf;
+		struct dma_desc *np, *p;
 		int entry, status;
-		struct dma_desc *p;
-		struct dma_desc *np;
 
 		entry = next_entry;
+		buf = &rx_q->buf_pool[entry];
 
 		if (priv->extend_desc)
 			p = (struct dma_desc *)(rx_q->dma_erx + entry);
@@ -3423,20 +3385,9 @@ static int stmmac_rx(struct stmmac_priv *priv, int limit, u32 queue)
 			stmmac_rx_extended_status(priv, &priv->dev->stats,
 					&priv->xstats, rx_q->dma_erx + entry);
 		if (unlikely(status == discard_frame)) {
+			page_pool_recycle_direct(rx_q->page_pool, buf->page);
 			priv->dev->stats.rx_errors++;
-			if (priv->hwts_rx_en && !priv->extend_desc) {
-				/* DESC2 & DESC3 will be overwritten by device
-				 * with timestamp value, hence reinitialize
-				 * them in stmmac_rx_refill() function so that
-				 * device can reuse it.
-				 */
-				dev_kfree_skb_any(rx_q->rx_skbuff[entry]);
-				rx_q->rx_skbuff[entry] = NULL;
-				dma_unmap_single(priv->device,
-						 rx_q->rx_skbuff_dma[entry],
-						 priv->dma_buf_sz,
-						 DMA_FROM_DEVICE);
-			}
+			buf->page = NULL;
 		} else {
 			struct sk_buff *skb;
 			int frame_len;
@@ -3476,58 +3427,20 @@ static int stmmac_rx(struct stmmac_priv *priv, int limit, u32 queue)
 					   frame_len, status);
 			}
 
-			/* The zero-copy is always used for all the sizes
-			 * in case of GMAC4 because it needs
-			 * to refill the used descriptors, always.
-			 */
-			if (unlikely(!xmac &&
-				     ((frame_len < priv->rx_copybreak) ||
-				     stmmac_rx_threshold_count(rx_q)))) {
-				skb = netdev_alloc_skb_ip_align(priv->dev,
-								frame_len);
-				if (unlikely(!skb)) {
-					if (net_ratelimit())
-						dev_warn(priv->device,
-							 "packet dropped\n");
-					priv->dev->stats.rx_dropped++;
-					continue;
-				}
-
-				dma_sync_single_for_cpu(priv->device,
-							rx_q->rx_skbuff_dma
-							[entry], frame_len,
-							DMA_FROM_DEVICE);
-				skb_copy_to_linear_data(skb,
-							rx_q->
-							rx_skbuff[entry]->data,
-							frame_len);
-
-				skb_put(skb, frame_len);
-				dma_sync_single_for_device(priv->device,
-							   rx_q->rx_skbuff_dma
-							   [entry], frame_len,
-							   DMA_FROM_DEVICE);
-			} else {
-				skb = rx_q->rx_skbuff[entry];
-				if (unlikely(!skb)) {
-					if (net_ratelimit())
-						netdev_err(priv->dev,
-							   "%s: Inconsistent Rx chain\n",
-							   priv->dev->name);
-					priv->dev->stats.rx_dropped++;
-					continue;
-				}
-				prefetch(skb->data - NET_IP_ALIGN);
-				rx_q->rx_skbuff[entry] = NULL;
-				rx_q->rx_zeroc_thresh++;
-
-				skb_put(skb, frame_len);
-				dma_unmap_single(priv->device,
-						 rx_q->rx_skbuff_dma[entry],
-						 priv->dma_buf_sz,
-						 DMA_FROM_DEVICE);
+			skb = netdev_alloc_skb_ip_align(priv->dev, frame_len);
+			if (unlikely(!skb)) {
+				priv->dev->stats.rx_dropped++;
+				continue;
 			}
 
+			dma_sync_single_for_cpu(priv->device, buf->addr,
+						frame_len, DMA_FROM_DEVICE);
+			skb_copy_to_linear_data(skb, page_address(buf->page),
+						frame_len);
+			skb_put(skb, frame_len);
+			dma_sync_single_for_device(priv->device, buf->addr,
+						   frame_len, DMA_FROM_DEVICE);
+
 			if (netif_msg_pktdata(priv)) {
 				netdev_dbg(priv->dev, "frame received (%dbytes)",
 					   frame_len);
@@ -3547,6 +3460,10 @@ static int stmmac_rx(struct stmmac_priv *priv, int limit, u32 queue)
 
 			napi_gro_receive(&ch->rx_napi, skb);
 
+			/* Data payload copied into SKB, page ready for recycle */
+			page_pool_recycle_direct(rx_q->page_pool, buf->page);
+			buf->page = NULL;
+
 			priv->dev->stats.rx_packets++;
 			priv->dev->stats.rx_bytes += frame_len;
 		}
-- 
2.7.4

Re: [PATCH net-next v2 3/3] net: stmmac: Introducing support for Page Pool

[Jesper Dangaard Brouer]

On Thu,  4 Jul 2019 17:04:14 +0200
Jose Abreu <Jose.Abreu@synopsys.com> wrote:

> @@ -1498,8 +1480,9 @@ static void free_dma_rx_desc_resources(struct stmmac_priv *priv)
>  					  sizeof(struct dma_extended_desc),
>  					  rx_q->dma_erx, rx_q->dma_rx_phy);
>  
> -		kfree(rx_q->rx_skbuff_dma);
> -		kfree(rx_q->rx_skbuff);
> +		kfree(rx_q->buf_pool);
> +		if (rx_q->page_pool && page_pool_request_shutdown(rx_q->page_pool))
> +			page_pool_free(rx_q->page_pool);
>  	}
>  }

This code is okay, but I would likely write it as:

  if (rx_q->page_pool) {
	page_pool_request_shutdown(rx_q->page_pool));
	page_pool_free(rx_q->page_pool);
  }

Because (as you noticed) page_pool_free() have some API misuse checks,
that will get triggered, and thus provide a warning of you forget to
update this when driver evolves.

-- 
Best regards,
  Jesper Dangaard Brouer
  MSc.CS, Principal Kernel Engineer at Red Hat
  LinkedIn: http://www.linkedin.com/in/brouer

RE: [PATCH net-next v2 3/3] net: stmmac: Introducing support for Page Pool

[Jose Abreu]

From: Jesper Dangaard Brouer <brouer@redhat.com>

> This code is okay, but I would likely write it as:
> 
>   if (rx_q->page_pool) {
> 	page_pool_request_shutdown(rx_q->page_pool));
> 	page_pool_free(rx_q->page_pool);
>   }
> 
> Because (as you noticed) page_pool_free() have some API misuse checks,
> that will get triggered, and thus provide a warning of you forget to
> update this when driver evolves.

Yeah, makes sense. I will update and resend. Thanks for the review!