[RESEND PATCH v8 net-next 00/15] net: mvpp2: Add TX Flow Control support

@@ -1,5 +1,6 @@
 * Marvell Armada 375 Ethernet Controller (PPv2.1)
   Marvell Armada 7K/8K Ethernet Controller (PPv2.2)
+  Marvell CN913X Ethernet Controller (PPv2.3)
 
 Required properties:
 

@@ -12,7 +13,7 @@ Required properties:
 	- common controller registers
 	- LMS registers
 	- one register area per Ethernet port
-  For "marvell,armada-7k-pp2", must contain the following register
+  For "marvell,armada-7k-pp2" used by 7K/8K and CN913X, must contain the following register
   sets:
 	- packet processor registers
 	- networking interfaces registers

@@ -37,6 +38,7 @@ Required properties (port):
   GOP (Group Of Ports) point of view. This ID is used to index the
   per-port registers in the second register area.
 - phy-mode: See ethernet.txt file in the same directory
+- cm3-mem: phandle to CM3 SRAM definitions
 
 Optional properties (port):
 

@@ -69,6 +69,8 @@
 			status = "disabled";
 			dma-coherent;
 
+			cm3-mem = <&CP11X_LABEL(cm3_sram)>;
+
 			CP11X_LABEL(eth0): eth0 {
 				interrupts = <39 IRQ_TYPE_LEVEL_HIGH>,
 					<43 IRQ_TYPE_LEVEL_HIGH>,

@@ -211,6 +213,14 @@
 			};
 		};
 
+		CP11X_LABEL(cm3_sram): cm3@220000 {
+			compatible = "mmio-sram";
+			reg = <0x220000 0x800>;
+			#address-cells = <1>;
+			#size-cells = <1>;
+			ranges = <0 0x220000 0x800>;
+		};
+
 		CP11X_LABEL(rtc): rtc@284000 {
 			compatible = "marvell,armada-8k-rtc";
 			reg = <0x284000 0x20>, <0x284080 0x24>;

@@ -748,6 +748,9 @@
 #define MVPP2_TX_FIFO_THRESHOLD(kb)	\
 		((kb) * 1024 - MVPP2_TX_FIFO_THRESHOLD_MIN)
 
+/* MSS Flow control */
+#define MSS_SRAM_SIZE	0x800
+
 /* RX buffer constants */
 #define MVPP2_SKB_SHINFO_SIZE \
 	SKB_DATA_ALIGN(sizeof(struct skb_shared_info))

@@ -925,6 +928,7 @@ struct mvpp2 {
 	/* Shared registers' base addresses */
 	void __iomem *lms_base;
 	void __iomem *iface_base;
+	void __iomem *cm3_base;
 
 	/* On PPv2.2, each "software thread" can access the base
 	 * register through a separate address space, each 64 KB apart

@@ -996,6 +1000,9 @@ struct mvpp2 {
 
 	/* page_pool allocator */
 	struct page_pool *page_pool[MVPP2_PORT_MAX_RXQ];
+
+	/* CM3 SRAM pool */
+	struct gen_pool *sram_pool;
 };
 
 struct mvpp2_pcpu_stats {

@@ -25,6 +25,7 @@
 #include <linux/of_net.h>
 #include <linux/of_address.h>
 #include <linux/of_device.h>
+#include <linux/genalloc.h>
 #include <linux/phy.h>
 #include <linux/phylink.h>
 #include <linux/phy/phy.h>

@@ -6846,6 +6847,44 @@ static int mvpp2_init(struct platform_device *pdev, struct mvpp2 *priv)
 	return 0;
 }
 
+static int mvpp2_get_sram(struct platform_device *pdev,
+			  struct mvpp2 *priv)
+{
+	struct device_node *dn = pdev->dev.of_node;
+	static bool defer_once;
+	struct resource *res;
+
+	if (has_acpi_companion(&pdev->dev)) {
+		res = platform_get_resource(pdev, IORESOURCE_MEM, 2);
+		if (!res) {
+			dev_warn(&pdev->dev, "ACPI is too old, Flow control not supported\n");
+			return 0;
+		}
+		priv->cm3_base = devm_ioremap_resource(&pdev->dev, res);
+		if (IS_ERR(priv->cm3_base))
+			return PTR_ERR(priv->cm3_base);
+	} else {
+		priv->sram_pool = of_gen_pool_get(dn, "cm3-mem", 0);
+		if (!priv->sram_pool) {
+			if (!defer_once) {
+				defer_once = true;
+				/* Try defer once */
+				return -EPROBE_DEFER;
+			}
+			dev_warn(&pdev->dev, "DT is too old, Flow control not supported\n");
+			return -ENOMEM;
+		}
+		/* cm3_base allocated with offset zero into the SRAM since mapping size
+		 * is equal to requested size.
+		 */
+		priv->cm3_base = (void __iomem *)gen_pool_alloc(priv->sram_pool,
+								MSS_SRAM_SIZE);
+		if (!priv->cm3_base)
+			return -ENOMEM;
+	}
+	return 0;
+}
+
 static int mvpp2_probe(struct platform_device *pdev)
 {
 	const struct acpi_device_id *acpi_id;

@@ -6902,6 +6941,13 @@ static int mvpp2_probe(struct platform_device *pdev)
 		priv->iface_base = devm_ioremap_resource(&pdev->dev, res);
 		if (IS_ERR(priv->iface_base))
 			return PTR_ERR(priv->iface_base);
+
+		/* Map CM3 SRAM */
+		err = mvpp2_get_sram(pdev, priv);
+		if (err == -EPROBE_DEFER)
+			return err;
+		else if (err)
+			dev_warn(&pdev->dev, "Fail to alloc CM3 SRAM\n");
 	}
 
 	if (priv->hw_version == MVPP22 && dev_of_node(&pdev->dev)) {

@@ -6947,11 +6993,13 @@ static int mvpp2_probe(struct platform_device *pdev)
 
 	if (dev_of_node(&pdev->dev)) {
 		priv->pp_clk = devm_clk_get(&pdev->dev, "pp_clk");
-		if (IS_ERR(priv->pp_clk))
-			return PTR_ERR(priv->pp_clk);
+		if (IS_ERR(priv->pp_clk)) {
+			err = PTR_ERR(priv->pp_clk);
+			goto err_cm3;
+		}
 		err = clk_prepare_enable(priv->pp_clk);
 		if (err < 0)
-			return err;
+			goto err_cm3;
 
 		priv->gop_clk = devm_clk_get(&pdev->dev, "gop_clk");
 		if (IS_ERR(priv->gop_clk)) {

@@ -7087,6 +7135,11 @@ static int mvpp2_probe(struct platform_device *pdev)
 	clk_disable_unprepare(priv->gop_clk);
 err_pp_clk:
 	clk_disable_unprepare(priv->pp_clk);
+err_cm3:
+	if (priv->sram_pool && priv->cm3_base)
+		gen_pool_free(priv->sram_pool, (unsigned long)priv->cm3_base,
+			      MSS_SRAM_SIZE);
+
 	return err;
 }
 

@@ -7127,6 +7180,10 @@ static int mvpp2_remove(struct platform_device *pdev)
 				  aggr_txq->descs_dma);
 	}
 
+	if (priv->sram_pool && priv->cm3_base)
+		gen_pool_free(priv->sram_pool, (unsigned long)priv->cm3_base,
+			      MSS_SRAM_SIZE);
+
 	if (is_acpi_node(port_fwnode))
 		return 0;
 

@@ -60,6 +60,9 @@
 /* Top Registers */
 #define MVPP2_MH_REG(port)			(0x5040 + 4 * (port))
 #define MVPP2_DSA_EXTENDED			BIT(5)
+#define MVPP2_VER_ID_REG			0x50b0
+#define MVPP2_VER_PP22				0x10
+#define MVPP2_VER_PP23				0x11
 
 /* Parser Registers */
 #define MVPP2_PRS_INIT_LOOKUP_REG		0x1000

@@ -469,7 +472,7 @@
 #define     MVPP22_GMAC_INT_SUM_MASK_LINK_STAT	BIT(1)
 #define	    MVPP22_GMAC_INT_SUM_MASK_PTP	BIT(2)
 
-/* Per-port XGMAC registers. PPv2.2 only, only for GOP port 0,
+/* Per-port XGMAC registers. PPv2.2 and PPv2.3, only for GOP port 0,
  * relative to port->base.
  */
 #define MVPP22_XLG_CTRL0_REG			0x100

@@ -506,7 +509,7 @@
 #define     MVPP22_XLG_CTRL4_MACMODSELECT_GMAC	BIT(12)
 #define     MVPP22_XLG_CTRL4_EN_IDLE_CHECK	BIT(14)
 
-/* SMI registers. PPv2.2 only, relative to priv->iface_base. */
+/* SMI registers. PPv2.2 and PPv2.3, relative to priv->iface_base. */
 #define MVPP22_SMI_MISC_CFG_REG			0x1204
 #define     MVPP22_SMI_POLLING_EN		BIT(10)
 

@@ -582,7 +585,7 @@
 #define MVPP2_QUEUE_NEXT_DESC(q, index) \
 	(((index) < (q)->last_desc) ? ((index) + 1) : 0)
 
-/* XPCS registers. PPv2.2 only */
+/* XPCS registers.PPv2.2 and PPv2.3 */
 #define MVPP22_MPCS_BASE(port)			(0x7000 + (port) * 0x1000)
 #define MVPP22_MPCS_CTRL			0x14
 #define     MVPP22_MPCS_CTRL_FWD_ERR_CONN	BIT(10)

@@ -593,7 +596,7 @@
 #define     MVPP22_MPCS_CLK_RESET_DIV_RATIO(n)	((n) << 4)
 #define     MVPP22_MPCS_CLK_RESET_DIV_SET	BIT(11)
 
-/* XPCS registers. PPv2.2 only */
+/* XPCS registers. PPv2.2 and PPv2.3 */
 #define MVPP22_XPCS_BASE(port)			(0x7400 + (port) * 0x1000)
 #define MVPP22_XPCS_CFG0			0x0
 #define     MVPP22_XPCS_CFG0_RESET_DIS		BIT(0)

@@ -930,15 +933,16 @@ struct mvpp2 {
 	void __iomem *iface_base;
 	void __iomem *cm3_base;
 
-	/* On PPv2.2, each "software thread" can access the base
+	/* On PPv2.2 and PPv2.3, each "software thread" can access the base
 	 * register through a separate address space, each 64 KB apart
 	 * from each other. Typically, such address spaces will be
 	 * used per CPU.
 	 */
 	void __iomem *swth_base[MVPP2_MAX_THREADS];
 
-	/* On PPv2.2, some port control registers are located into the system
-	 * controller space. These registers are accessible through a regmap.
+	/* On PPv2.2 and PPv2.3, some port control registers are located into
+	 * the system controller space. These registers are accessible
+	 * through a regmap.
 	 */
 	struct regmap *sysctrl_base;
 

@@ -980,7 +984,7 @@ struct mvpp2 {
 	u32 tclk;
 
 	/* HW version */
-	enum { MVPP21, MVPP22 } hw_version;
+	enum { MVPP21, MVPP22, MVPP23 } hw_version;
 
 	/* Maximum number of RXQs per port */
 	unsigned int max_port_rxqs;

@@ -1227,7 +1231,7 @@ struct mvpp21_rx_desc {
 	__le32 reserved8;
 };
 
-/* HW TX descriptor for PPv2.2 */
+/* HW TX descriptor for PPv2.2 and PPv2.3 */
 struct mvpp22_tx_desc {
 	__le32 command;
 	u8  packet_offset;

@@ -1239,7 +1243,7 @@ struct mvpp22_tx_desc {
 	__le64 buf_cookie_misc;
 };
 
-/* HW RX descriptor for PPv2.2 */
+/* HW RX descriptor for PPv2.2 and PPv2.3 */
 struct mvpp22_rx_desc {
 	__le32 status;
 	__le16 reserved1;

@@ -385,7 +385,7 @@ static int mvpp2_bm_pool_create(struct device *dev, struct mvpp2 *priv,
 	if (!IS_ALIGNED(size, 16))
 		return -EINVAL;
 
-	/* PPv2.1 needs 8 bytes per buffer pointer, PPv2.2 needs 16
+	/* PPv2.1 needs 8 bytes per buffer pointer, PPv2.2 and PPv2.3 needs 16
 	 * bytes per buffer pointer
 	 */
 	if (priv->hw_version == MVPP21)

@@ -1173,7 +1173,7 @@ static void mvpp2_interrupts_unmask(void *arg)
 	u32 val;
 	int i;
 
-	if (port->priv->hw_version != MVPP22)
+	if (port->priv->hw_version == MVPP21)
 		return;
 
 	if (mask)

@@ -5457,7 +5457,7 @@ static void mvpp2_rx_irqs_setup(struct mvpp2_port *port)
 		return;
 	}
 
-	/* Handle the more complicated PPv2.2 case */
+	/* Handle the more complicated PPv2.2 and PPv2.3 case */
 	for (i = 0; i < port->nqvecs; i++) {
 		struct mvpp2_queue_vector *qv = port->qvecs + i;
 

@@ -5634,7 +5634,7 @@ static bool mvpp22_port_has_legacy_tx_irqs(struct device_node *port_node,
 
 /* Checks if the port dt description has the required Tx interrupts:
  * - PPv2.1: there are no such interrupts.
- * - PPv2.2:
+ * - PPv2.2 and PPv2.3:
  *   - The old DTs have: "rx-shared", "tx-cpuX" with X in [0...3]
  *   - The new ones have: "hifX" with X in [0..8]
  *

@@ -6622,7 +6622,7 @@ static void mvpp22_rx_fifo_set_hw(struct mvpp2 *priv, int port, int data_size)
 	mvpp2_write(priv, MVPP2_RX_ATTR_FIFO_SIZE_REG(port), attr_size);
 }
 
-/* Initialize TX FIFO's: the total FIFO size is 48kB on PPv2.2.
+/* Initialize TX FIFO's: the total FIFO size is 48kB on PPv2.2 and PPv2.3.
  * 4kB fixed space must be assigned for the loopback port.
  * Redistribute remaining avialable 44kB space among all active ports.
  * Guarantee minimum 32kB for 10G port and 8kB for port 1, capable of 2.5G

@@ -6679,7 +6679,7 @@ static void mvpp22_tx_fifo_set_hw(struct mvpp2 *priv, int port, int size)
 	mvpp2_write(priv, MVPP22_TX_FIFO_THRESH_REG(port), threshold);
 }
 
-/* Initialize TX FIFO's: the total FIFO size is 19kB on PPv2.2.
+/* Initialize TX FIFO's: the total FIFO size is 19kB on PPv2.2 and PPv2.3.
  * 3kB fixed space must be assigned for the loopback port.
  * Redistribute remaining avialable 16kB space among all active ports.
  * The 10G interface should use 10kB (which is maximum possible size

@@ -7071,6 +7071,11 @@ static int mvpp2_probe(struct platform_device *pdev)
 			priv->port_map |= BIT(i);
 	}
 
+	if (priv->hw_version != MVPP21) {
+		if (mvpp2_read(priv, MVPP2_VER_ID_REG) == MVPP2_VER_PP23)
+			priv->hw_version = MVPP23;
+	}
+
 	/* Initialize network controller */
 	err = mvpp2_init(pdev, priv);
 	if (err < 0) {

@@ -320,7 +320,7 @@ static int mvpp2_get_nrxqs(struct mvpp2 *priv)
 {
 	unsigned int nrxqs;
 
-	if (priv->hw_version == MVPP22 && queue_mode == MVPP2_QDIST_SINGLE_MODE)
+	if (priv->hw_version != MVPP21 && queue_mode == MVPP2_QDIST_SINGLE_MODE)
 		return 1;
 
 	/* According to the PPv2.2 datasheet and our experiments on

@@ -447,7 +447,7 @@ static void mvpp2_bm_bufs_get_addrs(struct device *dev, struct mvpp2 *priv,
 				      MVPP2_BM_PHY_ALLOC_REG(bm_pool->id));
 	*phys_addr = mvpp2_thread_read(priv, thread, MVPP2_BM_VIRT_ALLOC_REG);
 
-	if (priv->hw_version == MVPP22) {
+	if (priv->hw_version != MVPP21) {
 		u32 val;
 		u32 dma_addr_highbits, phys_addr_highbits;
 

@@ -743,7 +743,7 @@ static inline void mvpp2_bm_pool_put(struct mvpp2_port *port, int pool,
 	if (test_bit(thread, &port->priv->lock_map))
 		spin_lock_irqsave(&port->bm_lock[thread], flags);
 
-	if (port->priv->hw_version == MVPP22) {
+	if (port->priv->hw_version != MVPP21) {
 		u32 val = 0;
 
 		if (sizeof(dma_addr_t) == 8)

@@ -1200,7 +1200,7 @@ static bool mvpp2_port_supports_xlg(struct mvpp2_port *port)
 
 static bool mvpp2_port_supports_rgmii(struct mvpp2_port *port)
 {
-	return !(port->priv->hw_version == MVPP22 && port->gop_id == 0);
+	return !(port->priv->hw_version != MVPP21 && port->gop_id == 0);
 }
 
 /* Port configuration routines */

@@ -1818,7 +1818,7 @@ static void mvpp2_mac_reset_assert(struct mvpp2_port *port)
 	      MVPP2_GMAC_PORT_RESET_MASK;
 	writel(val, port->base + MVPP2_GMAC_CTRL_2_REG);
 
-	if (port->priv->hw_version == MVPP22 && port->gop_id == 0) {
+	if (port->priv->hw_version != MVPP21 && port->gop_id == 0) {
 		val = readl(port->base + MVPP22_XLG_CTRL0_REG) &
 		      ~MVPP22_XLG_CTRL0_MAC_RESET_DIS;
 		writel(val, port->base + MVPP22_XLG_CTRL0_REG);

@@ -1831,7 +1831,7 @@ static void mvpp22_pcs_reset_assert(struct mvpp2_port *port)
 	void __iomem *mpcs, *xpcs;
 	u32 val;
 
-	if (port->priv->hw_version != MVPP22 || port->gop_id != 0)
+	if (port->priv->hw_version == MVPP21 || port->gop_id != 0)
 		return;
 
 	mpcs = priv->iface_base + MVPP22_MPCS_BASE(port->gop_id);

@@ -1852,7 +1852,7 @@ static void mvpp22_pcs_reset_deassert(struct mvpp2_port *port)
 	void __iomem *mpcs, *xpcs;
 	u32 val;
 
-	if (port->priv->hw_version != MVPP22 || port->gop_id != 0)
+	if (port->priv->hw_version == MVPP21 || port->gop_id != 0)
 		return;
 
 	mpcs = priv->iface_base + MVPP22_MPCS_BASE(port->gop_id);

@@ -4189,7 +4189,7 @@ static void mvpp2_start_dev(struct mvpp2_port *port)
 	/* Enable interrupts on all threads */
 	mvpp2_interrupts_enable(port);
 
-	if (port->priv->hw_version == MVPP22)
+	if (port->priv->hw_version != MVPP21)
 		mvpp22_mode_reconfigure(port);
 
 	if (port->phylink) {

@@ -4405,7 +4405,7 @@ static int mvpp2_open(struct net_device *dev)
 		valid = true;
 	}
 
-	if (priv->hw_version == MVPP22 && port->port_irq) {
+	if (priv->hw_version != MVPP21 && port->port_irq) {
 		err = request_irq(port->port_irq, mvpp2_port_isr, 0,
 				  dev->name, port);
 		if (err) {

@@ -6053,7 +6053,7 @@ static int mvpp2__mac_prepare(struct phylink_config *config, unsigned int mode,
 			     MVPP2_GMAC_PORT_RESET_MASK,
 			     MVPP2_GMAC_PORT_RESET_MASK);
 
-		if (port->priv->hw_version == MVPP22) {
+		if (port->priv->hw_version != MVPP21) {
 			mvpp22_gop_mask_irq(port);
 
 			phy_power_off(port->comphy);

@@ -6107,7 +6107,7 @@ static int mvpp2_mac_finish(struct phylink_config *config, unsigned int mode,
 {
 	struct mvpp2_port *port = mvpp2_phylink_to_port(config);
 
-	if (port->priv->hw_version == MVPP22 &&
+	if (port->priv->hw_version != MVPP21 &&
 	    port->phy_interface != interface) {
 		port->phy_interface = interface;
 

@@ -6787,7 +6787,7 @@ static int mvpp2_init(struct platform_device *pdev, struct mvpp2 *priv)
 	if (dram_target_info)
 		mvpp2_conf_mbus_windows(dram_target_info, priv);
 
-	if (priv->hw_version == MVPP22)
+	if (priv->hw_version != MVPP21)
 		mvpp2_axi_init(priv);
 
 	/* Disable HW PHY polling */

@@ -6950,7 +6950,7 @@ static int mvpp2_probe(struct platform_device *pdev)
 			dev_warn(&pdev->dev, "Fail to alloc CM3 SRAM\n");
 	}
 
-	if (priv->hw_version == MVPP22 && dev_of_node(&pdev->dev)) {
+	if (priv->hw_version != MVPP21 && dev_of_node(&pdev->dev)) {
 		priv->sysctrl_base =
 			syscon_regmap_lookup_by_phandle(pdev->dev.of_node,
 							"marvell,system-controller");

@@ -6963,7 +6963,7 @@ static int mvpp2_probe(struct platform_device *pdev)
 			priv->sysctrl_base = NULL;
 	}
 
-	if (priv->hw_version == MVPP22 &&
+	if (priv->hw_version != MVPP21 &&
 	    mvpp2_get_nrxqs(priv) * 2 <= MVPP2_BM_MAX_POOLS)
 		priv->percpu_pools = 1;
 

@@ -7010,7 +7010,7 @@ static int mvpp2_probe(struct platform_device *pdev)
 		if (err < 0)
 			goto err_pp_clk;
 
-		if (priv->hw_version == MVPP22) {
+		if (priv->hw_version != MVPP21) {
 			priv->mg_clk = devm_clk_get(&pdev->dev, "mg_clk");
 			if (IS_ERR(priv->mg_clk)) {
 				err = PTR_ERR(priv->mg_clk);

@@ -7051,7 +7051,7 @@ static int mvpp2_probe(struct platform_device *pdev)
 		return -EINVAL;
 	}
 
-	if (priv->hw_version == MVPP22) {
+	if (priv->hw_version != MVPP21) {
 		err = dma_set_mask(&pdev->dev, MVPP2_DESC_DMA_MASK);
 		if (err)
 			goto err_axi_clk;

@@ -7126,10 +7126,10 @@ static int mvpp2_probe(struct platform_device *pdev)
 	clk_disable_unprepare(priv->axi_clk);
 
 err_mg_core_clk:
-	if (priv->hw_version == MVPP22)
+	if (priv->hw_version != MVPP21)
 		clk_disable_unprepare(priv->mg_core_clk);
 err_mg_clk:
-	if (priv->hw_version == MVPP22)
+	if (priv->hw_version != MVPP21)
 		clk_disable_unprepare(priv->mg_clk);
 err_gop_clk:
 	clk_disable_unprepare(priv->gop_clk);

@@ -715,8 +715,8 @@
 #define MVPP2_PORT_MAX_RXQ		32
 
 /* Max number of Rx descriptors */
-#define MVPP2_MAX_RXD_MAX		1024
-#define MVPP2_MAX_RXD_DFLT		128
+#define MVPP2_MAX_RXD_MAX		2048
+#define MVPP2_MAX_RXD_DFLT		1024
 
 /* Max number of Tx descriptors */
 #define MVPP2_MAX_TXD_MAX		2048

@@ -851,8 +851,8 @@ enum mvpp22_ptp_packet_format {
 #define MVPP22_PTP_TIMESTAMPQUEUESELECT	BIT(18)
 
 /* BM constants */
-#define MVPP2_BM_JUMBO_BUF_NUM		512
-#define MVPP2_BM_LONG_BUF_NUM		1024
+#define MVPP2_BM_JUMBO_BUF_NUM		2048
+#define MVPP2_BM_LONG_BUF_NUM		2048
 #define MVPP2_BM_SHORT_BUF_NUM		2048
 #define MVPP2_BM_POOL_SIZE_MAX		(16*1024 - MVPP2_BM_POOL_PTR_ALIGN/4)
 #define MVPP2_BM_POOL_PTR_ALIGN		128

@@ -596,6 +596,15 @@
 #define     MVPP22_MPCS_CLK_RESET_DIV_RATIO(n)	((n) << 4)
 #define     MVPP22_MPCS_CLK_RESET_DIV_SET	BIT(11)
 
+/* FCA registers. PPv2.2 and PPv2.3 */
+#define MVPP22_FCA_BASE(port)			(0x7600 + (port) * 0x1000)
+#define MVPP22_FCA_REG_SIZE			16
+#define MVPP22_FCA_REG_MASK			0xFFFF
+#define MVPP22_FCA_CONTROL_REG			0x0
+#define MVPP22_FCA_ENABLE_PERIODIC		BIT(11)
+#define MVPP22_PERIODIC_COUNTER_LSB_REG		(0x110)
+#define MVPP22_PERIODIC_COUNTER_MSB_REG		(0x114)
+
 /* XPCS registers. PPv2.2 and PPv2.3 */
 #define MVPP22_XPCS_BASE(port)			(0x7400 + (port) * 0x1000)
 #define MVPP22_XPCS_CFG0			0x0

@@ -752,7 +761,9 @@
 		((kb) * 1024 - MVPP2_TX_FIFO_THRESHOLD_MIN)
 
 /* MSS Flow control */
-#define MSS_SRAM_SIZE	0x800
+#define MSS_SRAM_SIZE		0x800
+#define FC_QUANTA		0xFFFF
+#define FC_CLK_DIVIDER		100
 
 /* RX buffer constants */
 #define MVPP2_SKB_SHINFO_SIZE \

@@ -1281,6 +1281,49 @@ static void mvpp22_gop_init_10gkr(struct mvpp2_port *port)
 	writel(val, mpcs + MVPP22_MPCS_CLK_RESET);
 }
 
+static void mvpp22_gop_fca_enable_periodic(struct mvpp2_port *port, bool en)
+{
+	struct mvpp2 *priv = port->priv;
+	void __iomem *fca = priv->iface_base + MVPP22_FCA_BASE(port->gop_id);
+	u32 val;
+
+	val = readl(fca + MVPP22_FCA_CONTROL_REG);
+	val &= ~MVPP22_FCA_ENABLE_PERIODIC;
+	if (en)
+		val |= MVPP22_FCA_ENABLE_PERIODIC;
+	writel(val, fca + MVPP22_FCA_CONTROL_REG);
+}
+
+static void mvpp22_gop_fca_set_timer(struct mvpp2_port *port, u32 timer)
+{
+	struct mvpp2 *priv = port->priv;
+	void __iomem *fca = priv->iface_base + MVPP22_FCA_BASE(port->gop_id);
+	u32 lsb, msb;
+
+	lsb = timer & MVPP22_FCA_REG_MASK;
+	msb = timer >> MVPP22_FCA_REG_SIZE;
+
+	writel(lsb, fca + MVPP22_PERIODIC_COUNTER_LSB_REG);
+	writel(msb, fca + MVPP22_PERIODIC_COUNTER_MSB_REG);
+}
+
+/* Set Flow Control timer x100 faster than pause quanta to ensure that link
+ * partner won't send traffic if port is in XOFF mode.
+ */
+static void mvpp22_gop_fca_set_periodic_timer(struct mvpp2_port *port)
+{
+	u32 timer;
+
+	timer = (port->priv->tclk / (USEC_PER_SEC * FC_CLK_DIVIDER))
+		* FC_QUANTA;
+
+	mvpp22_gop_fca_enable_periodic(port, false);
+
+	mvpp22_gop_fca_set_timer(port, timer);
+
+	mvpp22_gop_fca_enable_periodic(port, true);
+}
+
 static int mvpp22_gop_init(struct mvpp2_port *port)
 {
 	struct mvpp2 *priv = port->priv;

@@ -1325,6 +1368,8 @@ static int mvpp22_gop_init(struct mvpp2_port *port)
 	val |= GENCONF_SOFT_RESET1_GOP;
 	regmap_write(priv->sysctrl_base, GENCONF_SOFT_RESET1, val);
 
+	mvpp22_gop_fca_set_periodic_timer(port);
+
 unsupported_conf:
 	return 0;
 

@@ -295,6 +295,8 @@
 #define     MVPP2_PON_CAUSE_TXP_OCCUP_DESC_ALL_MASK	0x3fc00000
 #define     MVPP2_PON_CAUSE_MISC_SUM_MASK		BIT(31)
 #define MVPP2_ISR_MISC_CAUSE_REG		0x55b0
+#define MVPP2_ISR_RX_ERR_CAUSE_REG(port)	(0x5520 + 4 * (port))
+#define     MVPP2_ISR_RX_ERR_CAUSE_NONOCC_MASK	0x00ff
 
 /* Buffer Manager registers */
 #define MVPP2_BM_POOL_BASE_REG(pool)		(0x6000 + ((pool) * 4))

@@ -764,6 +766,7 @@
 #define MSS_SRAM_SIZE		0x800
 #define FC_QUANTA		0xFFFF
 #define FC_CLK_DIVIDER		100
+#define MSS_THRESHOLD_STOP	768
 
 /* RX buffer constants */
 #define MVPP2_SKB_SHINFO_SIZE \

@@ -1134,14 +1134,19 @@ static inline void mvpp2_qvec_interrupt_disable(struct mvpp2_queue_vector *qvec)
 static void mvpp2_interrupts_mask(void *arg)
 {
 	struct mvpp2_port *port = arg;
+	int cpu = smp_processor_id();
+	u32 thread;
 
 	/* If the thread isn't used, don't do anything */
-	if (smp_processor_id() > port->priv->nthreads)
+	if (cpu > port->priv->nthreads)
 		return;
 
-	mvpp2_thread_write(port->priv,
-			   mvpp2_cpu_to_thread(port->priv, smp_processor_id()),
+	thread = mvpp2_cpu_to_thread(port->priv, cpu);
+
+	mvpp2_thread_write(port->priv, thread,
 			   MVPP2_ISR_RX_TX_MASK_REG(port->id), 0);
+	mvpp2_thread_write(port->priv, thread,
+			   MVPP2_ISR_RX_ERR_CAUSE_REG(port->id), 0);
 }
 
 /* Unmask the current thread's Rx/Tx interrupts.

@@ -1151,20 +1156,25 @@ static void mvpp2_interrupts_mask(void *arg)
 static void mvpp2_interrupts_unmask(void *arg)
 {
 	struct mvpp2_port *port = arg;
-	u32 val;
+	int cpu = smp_processor_id();
+	u32 val, thread;
 
 	/* If the thread isn't used, don't do anything */
-	if (smp_processor_id() > port->priv->nthreads)
+	if (cpu > port->priv->nthreads)
 		return;
 
+	thread = mvpp2_cpu_to_thread(port->priv, cpu);
+
 	val = MVPP2_CAUSE_MISC_SUM_MASK |
 		MVPP2_CAUSE_RXQ_OCCUP_DESC_ALL_MASK(port->priv->hw_version);
 	if (port->has_tx_irqs)
 		val |= MVPP2_CAUSE_TXQ_OCCUP_DESC_ALL_MASK;
 
-	mvpp2_thread_write(port->priv,
-			   mvpp2_cpu_to_thread(port->priv, smp_processor_id()),
+	mvpp2_thread_write(port->priv, thread,
 			   MVPP2_ISR_RX_TX_MASK_REG(port->id), val);
+	mvpp2_thread_write(port->priv, thread,
+			   MVPP2_ISR_RX_ERR_CAUSE_REG(port->id),
+			   MVPP2_ISR_RX_ERR_CAUSE_NONOCC_MASK);
 }
 
 static void

@@ -1189,6 +1199,9 @@ static void mvpp2_interrupts_unmask(void *arg)
 
 		mvpp2_thread_write(port->priv, v->sw_thread_id,
 				   MVPP2_ISR_RX_TX_MASK_REG(port->id), val);
+		mvpp2_thread_write(port->priv, v->sw_thread_id,
+				   MVPP2_ISR_RX_ERR_CAUSE_REG(port->id),
+				   MVPP2_ISR_RX_ERR_CAUSE_NONOCC_MASK);
 	}
 }
 

@@ -2394,6 +2407,20 @@ static void mvpp2_txp_max_tx_size_set(struct mvpp2_port *port)
 	}
 }
 
+/* Set the number of non-occupied descriptors threshold */
+static void mvpp2_set_rxq_free_tresh(struct mvpp2_port *port,
+				     struct mvpp2_rx_queue *rxq)
+{
+	u32 val;
+
+	mvpp2_write(port->priv, MVPP2_RXQ_NUM_REG, rxq->id);
+
+	val = mvpp2_read(port->priv, MVPP2_RXQ_THRESH_REG);
+	val &= ~MVPP2_RXQ_NON_OCCUPIED_MASK;
+	val |= MSS_THRESHOLD_STOP << MVPP2_RXQ_NON_OCCUPIED_OFFSET;
+	mvpp2_write(port->priv, MVPP2_RXQ_THRESH_REG, val);
+}
+
 /* Set the number of packets that will be received before Rx interrupt
  * will be generated by HW.
  */

@@ -2649,6 +2676,9 @@ static int mvpp2_rxq_init(struct mvpp2_port *port,
 	mvpp2_rx_pkts_coal_set(port, rxq);
 	mvpp2_rx_time_coal_set(port, rxq);
 
+	/* Set the number of non occupied descriptors threshold */
+	mvpp2_set_rxq_free_tresh(port, rxq);
+
 	/* Add number of descriptors ready for receiving packets */
 	mvpp2_rxq_status_update(port, rxq->id, 0, rxq->size);
 

@@ -763,10 +763,12 @@
 		((kb) * 1024 - MVPP2_TX_FIFO_THRESHOLD_MIN)
 
 /* MSS Flow control */
-#define MSS_SRAM_SIZE		0x800
-#define FC_QUANTA		0xFFFF
-#define FC_CLK_DIVIDER		100
-#define MSS_THRESHOLD_STOP	768
+#define MSS_SRAM_SIZE			0x800
+#define MSS_FC_COM_REG			0
+#define FLOW_CONTROL_ENABLE_BIT		BIT(0)
+#define FC_QUANTA			0xFFFF
+#define FC_CLK_DIVIDER			100
+#define MSS_THRESHOLD_STOP		768
 
 /* RX buffer constants */
 #define MVPP2_SKB_SHINFO_SIZE \

@@ -1021,6 +1023,9 @@ struct mvpp2 {
 
 	/* CM3 SRAM pool */
 	struct gen_pool *sram_pool;
+
+	/* Global TX Flow Control config */
+	bool global_tx_fc;
 };
 
 struct mvpp2_pcpu_stats {

@@ -92,6 +92,16 @@ static inline u32 mvpp2_cpu_to_thread(struct mvpp2 *priv, int cpu)
 	return cpu % priv->nthreads;
 }
 
+static void mvpp2_cm3_write(struct mvpp2 *priv, u32 offset, u32 data)
+{
+	writel(data, priv->cm3_base + offset);
+}
+
+static u32 mvpp2_cm3_read(struct mvpp2 *priv, u32 offset)
+{
+	return readl(priv->cm3_base + offset);
+}
+
 static struct page_pool *
 mvpp2_create_page_pool(struct device *dev, int num, int len,
 		       enum dma_data_direction dma_dir)

@@ -5951,6 +5961,11 @@ static void mvpp2_phylink_validate(struct phylink_config *config,
 	phylink_set(mask, Autoneg);
 	phylink_set_port_modes(mask);
 
+	if (port->priv->global_tx_fc) {
+		phylink_set(mask, Pause);
+		phylink_set(mask, Asym_Pause);
+	}
+
 	switch (state->interface) {
 	case PHY_INTERFACE_MODE_10GBASER:
 	case PHY_INTERFACE_MODE_XAUI:

@@ -6969,7 +6984,7 @@ static int mvpp2_probe(struct platform_device *pdev)
 	struct resource *res;
 	void __iomem *base;
 	int i, shared;
-	int err;
+	int err, val;
 
 	priv = devm_kzalloc(&pdev->dev, sizeof(*priv), GFP_KERNEL);
 	if (!priv)

@@ -7023,6 +7038,10 @@ static int mvpp2_probe(struct platform_device *pdev)
 			return err;
 		else if (err)
 			dev_warn(&pdev->dev, "Fail to alloc CM3 SRAM\n");
+
+		/* Enable global Flow Control only if handler to SRAM not NULL */
+		if (priv->cm3_base)
+			priv->global_tx_fc = true;
 	}
 
 	if (priv->hw_version != MVPP21 && dev_of_node(&pdev->dev)) {

@@ -7190,6 +7209,15 @@ static int mvpp2_probe(struct platform_device *pdev)
 		goto err_port_probe;
 	}
 
+	/* Enable global flow control. In this stage global
+	 * flow control enabled, but still disabled per port.
+	 */
+	if (priv->global_tx_fc && priv->hw_version != MVPP21) {
+		val = mvpp2_cm3_read(priv, MSS_FC_COM_REG);
+		val |= FLOW_CONTROL_ENABLE_BIT;
+		mvpp2_cm3_write(priv, MSS_FC_COM_REG, val);
+	}
+
 	mvpp2_dbgfs_init(priv, pdev->name);
 
 	platform_set_drvdata(pdev, priv);

@@ -766,9 +766,36 @@
 #define MSS_SRAM_SIZE			0x800
 #define MSS_FC_COM_REG			0
 #define FLOW_CONTROL_ENABLE_BIT		BIT(0)
+#define FLOW_CONTROL_UPDATE_COMMAND_BIT	BIT(31)
 #define FC_QUANTA			0xFFFF
 #define FC_CLK_DIVIDER			100
-#define MSS_THRESHOLD_STOP		768
+
+#define MSS_RXQ_TRESH_BASE		0x200
+#define MSS_RXQ_TRESH_OFFS		4
+#define MSS_RXQ_TRESH_REG(q, fq)	(MSS_RXQ_TRESH_BASE + (((q) + (fq)) \
+					* MSS_RXQ_TRESH_OFFS))
+
+#define MSS_RXQ_TRESH_START_MASK	0xFFFF
+#define MSS_RXQ_TRESH_STOP_MASK		(0xFFFF << MSS_RXQ_TRESH_STOP_OFFS)
+#define MSS_RXQ_TRESH_STOP_OFFS		16
+
+#define MSS_RXQ_ASS_BASE	0x80
+#define MSS_RXQ_ASS_OFFS	4
+#define MSS_RXQ_ASS_PER_REG	4
+#define MSS_RXQ_ASS_PER_OFFS	8
+#define MSS_RXQ_ASS_PORTID_OFFS	0
+#define MSS_RXQ_ASS_PORTID_MASK	0x3
+#define MSS_RXQ_ASS_HOSTID_OFFS	2
+#define MSS_RXQ_ASS_HOSTID_MASK	0x3F
+
+#define MSS_RXQ_ASS_Q_BASE(q, fq) ((((q) + (fq)) % MSS_RXQ_ASS_PER_REG)	 \
+				  * MSS_RXQ_ASS_PER_OFFS)
+#define MSS_RXQ_ASS_PQ_BASE(q, fq) ((((q) + (fq)) / MSS_RXQ_ASS_PER_REG) \
+				   * MSS_RXQ_ASS_OFFS)
+#define MSS_RXQ_ASS_REG(q, fq) (MSS_RXQ_ASS_BASE + MSS_RXQ_ASS_PQ_BASE(q, fq))
+
+#define MSS_THRESHOLD_STOP	768
+#define MSS_THRESHOLD_START	1024
 
 /* RX buffer constants */
 #define MVPP2_SKB_SHINFO_SIZE \

@@ -1026,6 +1053,9 @@ struct mvpp2 {
 
 	/* Global TX Flow Control config */
 	bool global_tx_fc;
+
+	/* Spinlocks for CM3 shared memory configuration */
+	spinlock_t mss_spinlock;
 };
 
 struct mvpp2_pcpu_stats {

@@ -1188,6 +1218,9 @@ struct mvpp2_port {
 	bool rx_hwtstamp;
 	enum hwtstamp_tx_types tx_hwtstamp_type;
 	struct mvpp2_hwtstamp_queue tx_hwtstamp_queue[2];
+
+	/* Firmware TX flow control */
+	bool tx_fc;
 };
 
 /* The mvpp2_tx_desc and mvpp2_rx_desc structures describe the

@@ -742,6 +742,110 @@ static void *mvpp2_buf_alloc(struct mvpp2_port *port,
 	return data;
 }
 
+/* Routine enable flow control for RXQs condition */
+static void mvpp2_rxq_enable_fc(struct mvpp2_port *port)
+{
+	int val, cm3_state, host_id, q;
+	int fq = port->first_rxq;
+	unsigned long flags;
+
+	spin_lock_irqsave(&port->priv->mss_spinlock, flags);
+
+	/* Remove Flow control enable bit to prevent race between FW and Kernel
+	 * If Flow control was enabled, it would be re-enabled.
+	 */
+	val = mvpp2_cm3_read(port->priv, MSS_FC_COM_REG);
+	cm3_state = (val & FLOW_CONTROL_ENABLE_BIT);
+	val &= ~FLOW_CONTROL_ENABLE_BIT;
+	mvpp2_cm3_write(port->priv, MSS_FC_COM_REG, val);
+
+	/* Set same Flow control for all RXQs */
+	for (q = 0; q < port->nrxqs; q++) {
+		/* Set stop and start Flow control RXQ thresholds */
+		val = MSS_THRESHOLD_START;
+		val |= (MSS_THRESHOLD_STOP << MSS_RXQ_TRESH_STOP_OFFS);
+		mvpp2_cm3_write(port->priv, MSS_RXQ_TRESH_REG(q, fq), val);
+
+		val = mvpp2_cm3_read(port->priv, MSS_RXQ_ASS_REG(q, fq));
+		/* Set RXQ port ID */
+		val &= ~(MSS_RXQ_ASS_PORTID_MASK << MSS_RXQ_ASS_Q_BASE(q, fq));
+		val |= (port->id << MSS_RXQ_ASS_Q_BASE(q, fq));
+		val &= ~(MSS_RXQ_ASS_HOSTID_MASK << (MSS_RXQ_ASS_Q_BASE(q, fq)
+			+ MSS_RXQ_ASS_HOSTID_OFFS));
+
+		/* Calculate RXQ host ID:
+		 * In Single queue mode: Host ID equal to Host ID used for
+		 *			 shared RX interrupt
+		 * In Multi queue mode: Host ID equal to number of
+		 *			RXQ ID / number of CoS queues
+		 * In Single resource mode: Host ID always equal to 0
+		 */
+		if (queue_mode == MVPP2_QDIST_SINGLE_MODE)
+			host_id = port->nqvecs;
+		else if (queue_mode == MVPP2_QDIST_MULTI_MODE)
+			host_id = q;
+		else
+			host_id = 0;
+
+		/* Set RXQ host ID */
+		val |= (host_id << (MSS_RXQ_ASS_Q_BASE(q, fq)
+			+ MSS_RXQ_ASS_HOSTID_OFFS));
+
+		mvpp2_cm3_write(port->priv, MSS_RXQ_ASS_REG(q, fq), val);
+	}
+
+	/* Notify Firmware that Flow control config space ready for update */
+	val = mvpp2_cm3_read(port->priv, MSS_FC_COM_REG);
+	val |= FLOW_CONTROL_UPDATE_COMMAND_BIT;
+	val |= cm3_state;
+	mvpp2_cm3_write(port->priv, MSS_FC_COM_REG, val);
+
+	spin_unlock_irqrestore(&port->priv->mss_spinlock, flags);
+}
+
+/* Routine disable flow control for RXQs condition */
+static void mvpp2_rxq_disable_fc(struct mvpp2_port *port)
+{
+	int val, cm3_state, q;
+	unsigned long flags;
+	int fq = port->first_rxq;
+
+	spin_lock_irqsave(&port->priv->mss_spinlock, flags);
+
+	/* Remove Flow control enable bit to prevent race between FW and Kernel
+	 * If Flow control was enabled, it would be re-enabled.
+	 */
+	val = mvpp2_cm3_read(port->priv, MSS_FC_COM_REG);
+	cm3_state = (val & FLOW_CONTROL_ENABLE_BIT);
+	val &= ~FLOW_CONTROL_ENABLE_BIT;
+	mvpp2_cm3_write(port->priv, MSS_FC_COM_REG, val);
+
+	/* Disable Flow control for all RXQs */
+	for (q = 0; q < port->nrxqs; q++) {
+		/* Set threshold 0 to disable Flow control */
+		val = 0;
+		val |= (0 << MSS_RXQ_TRESH_STOP_OFFS);
+		mvpp2_cm3_write(port->priv, MSS_RXQ_TRESH_REG(q, fq), val);
+
+		val = mvpp2_cm3_read(port->priv, MSS_RXQ_ASS_REG(q, fq));
+
+		val &= ~(MSS_RXQ_ASS_PORTID_MASK << MSS_RXQ_ASS_Q_BASE(q, fq));
+
+		val &= ~(MSS_RXQ_ASS_HOSTID_MASK << (MSS_RXQ_ASS_Q_BASE(q, fq)
+			+ MSS_RXQ_ASS_HOSTID_OFFS));
+
+		mvpp2_cm3_write(port->priv, MSS_RXQ_ASS_REG(q, fq), val);
+	}
+
+	/* Notify Firmware that Flow control config space ready for update */
+	val = mvpp2_cm3_read(port->priv, MSS_FC_COM_REG);
+	val |= FLOW_CONTROL_UPDATE_COMMAND_BIT;
+	val |= cm3_state;
+	mvpp2_cm3_write(port->priv, MSS_FC_COM_REG, val);
+
+	spin_unlock_irqrestore(&port->priv->mss_spinlock, flags);
+}
+
 /* Release buffer to BM */
 static inline void mvpp2_bm_pool_put(struct mvpp2_port *port, int pool,
 				     dma_addr_t buf_dma_addr,

@@ -3006,6 +3110,9 @@ static void mvpp2_cleanup_rxqs(struct mvpp2_port *port)
 
 	for (queue = 0; queue < port->nrxqs; queue++)
 		mvpp2_rxq_deinit(port, port->rxqs[queue]);
+
+	if (port->tx_fc)
+		mvpp2_rxq_disable_fc(port);
 }
 
 /* Init all Rx queues for port */

@@ -3018,6 +3125,10 @@ static int mvpp2_setup_rxqs(struct mvpp2_port *port)
 		if (err)
 			goto err_cleanup;
 	}
+
+	if (port->tx_fc)
+		mvpp2_rxq_enable_fc(port);
+
 	return 0;
 
 err_cleanup:

@@ -4317,6 +4428,8 @@ static int mvpp2_check_ringparam_valid(struct net_device *dev,
 
 	if (ring->rx_pending > MVPP2_MAX_RXD_MAX)
 		new_rx_pending = MVPP2_MAX_RXD_MAX;
+	else if (ring->rx_pending < MSS_THRESHOLD_START)
+		new_rx_pending = MSS_THRESHOLD_START;
 	else if (!IS_ALIGNED(ring->rx_pending, 16))
 		new_rx_pending = ALIGN(ring->rx_pending, 16);
 

@@ -7170,6 +7283,9 @@ static int mvpp2_probe(struct platform_device *pdev)
 			priv->hw_version = MVPP23;
 	}
 
+	/* Init mss lock */
+	spin_lock_init(&priv->mss_spinlock);
+
 	/* Initialize network controller */
 	err = mvpp2_init(pdev, priv);
 	if (err < 0) {

@@ -775,6 +775,19 @@
 #define MSS_RXQ_TRESH_REG(q, fq)	(MSS_RXQ_TRESH_BASE + (((q) + (fq)) \
 					* MSS_RXQ_TRESH_OFFS))
 
+#define MSS_BUF_POOL_BASE		0x40
+#define MSS_BUF_POOL_OFFS		4
+#define MSS_BUF_POOL_REG(id)		(MSS_BUF_POOL_BASE		\
+					+ (id) * MSS_BUF_POOL_OFFS)
+
+#define MSS_BUF_POOL_STOP_MASK		0xFFF
+#define MSS_BUF_POOL_START_MASK		(0xFFF << MSS_BUF_POOL_START_OFFS)
+#define MSS_BUF_POOL_START_OFFS		12
+#define MSS_BUF_POOL_PORTS_MASK		(0xF << MSS_BUF_POOL_PORTS_OFFS)
+#define MSS_BUF_POOL_PORTS_OFFS		24
+#define MSS_BUF_POOL_PORT_OFFS(id)	(0x1 <<				\
+					((id) + MSS_BUF_POOL_PORTS_OFFS))
+
 #define MSS_RXQ_TRESH_START_MASK	0xFFFF
 #define MSS_RXQ_TRESH_STOP_MASK		(0xFFFF << MSS_RXQ_TRESH_STOP_OFFS)
 #define MSS_RXQ_TRESH_STOP_OFFS		16

@@ -846,6 +846,59 @@ static void mvpp2_rxq_disable_fc(struct mvpp2_port *port)
 	spin_unlock_irqrestore(&port->priv->mss_spinlock, flags);
 }
 
+/* Routine disable/enable flow control for BM pool condition */
+static void mvpp2_bm_pool_update_fc(struct mvpp2_port *port,
+				    struct mvpp2_bm_pool *pool,
+				    bool en)
+{
+	int val, cm3_state;
+	unsigned long flags;
+
+	spin_lock_irqsave(&port->priv->mss_spinlock, flags);
+
+	/* Remove Flow control enable bit to prevent race between FW and Kernel
+	 * If Flow control were enabled, it would be re-enabled.
+	 */
+	val = mvpp2_cm3_read(port->priv, MSS_FC_COM_REG);
+	cm3_state = (val & FLOW_CONTROL_ENABLE_BIT);
+	val &= ~FLOW_CONTROL_ENABLE_BIT;
+	mvpp2_cm3_write(port->priv, MSS_FC_COM_REG, val);
+
+	/* Check if BM pool should be enabled/disable */
+	if (en) {
+		/* Set BM pool start and stop thresholds per port */
+		val = mvpp2_cm3_read(port->priv, MSS_BUF_POOL_REG(pool->id));
+		val |= MSS_BUF_POOL_PORT_OFFS(port->id);
+		val &= ~MSS_BUF_POOL_START_MASK;
+		val |= (MSS_THRESHOLD_START << MSS_BUF_POOL_START_OFFS);
+		val &= ~MSS_BUF_POOL_STOP_MASK;
+		val |= MSS_THRESHOLD_STOP;
+		mvpp2_cm3_write(port->priv, MSS_BUF_POOL_REG(pool->id), val);
+	} else {
+		/* Remove BM pool from the port */
+		val = mvpp2_cm3_read(port->priv, MSS_BUF_POOL_REG(pool->id));
+		val &= ~MSS_BUF_POOL_PORT_OFFS(port->id);
+
+		/* Zero BM pool start and stop thresholds to disable pool
+		 * flow control if pool empty (not used by any port)
+		 */
+		if (!pool->buf_num) {
+			val &= ~MSS_BUF_POOL_START_MASK;
+			val &= ~MSS_BUF_POOL_STOP_MASK;
+		}
+
+		mvpp2_cm3_write(port->priv, MSS_BUF_POOL_REG(pool->id), val);
+	}
+
+	/* Notify Firmware that Flow control config space ready for update */
+	val = mvpp2_cm3_read(port->priv, MSS_FC_COM_REG);
+	val |= FLOW_CONTROL_UPDATE_COMMAND_BIT;
+	val |= cm3_state;
+	mvpp2_cm3_write(port->priv, MSS_FC_COM_REG, val);
+
+	spin_unlock_irqrestore(&port->priv->mss_spinlock, flags);
+}
+
 /* Release buffer to BM */
 static inline void mvpp2_bm_pool_put(struct mvpp2_port *port, int pool,
 				     dma_addr_t buf_dma_addr,