Renesas Ethernet AVB driver proper

Ethernet AVB includes an Gigabit Ethernet controller (E-MAC) that is basically
compatible with SuperH Gigabit Ethernet E-MAC.  Ethernet AVB has  a  dedicated
direct memory access controller (AVB-DMAC) that is a new design compared to the
SuperH E-DMAC. The AVB-DMAC is compliant with 3 standards formulated for IEEE
802.1BA: IEEE 802.1AS timing and synchronization protocol, IEEE 802.1Qav real-
time transfer, and the IEEE 802.1Qat stream reservation protocol.

The  driver only supports device tree probing, so the binding document is
included in this patch.

Based on the original patches by Mitsuhiro Kimura.

Signed-off-by: Mitsuhiro Kimura <mitsuhiro.kimura.kc@renesas.com>
Signed-off-by: Sergei Shtylyov <sergei.shtylyov@cogentembedded.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

5 files changed, 2687 insertions, 0 deletions

diff --git a/Documentation/devicetree/bindings/net/renesas,ravb.txt b/Documentation/devicetree/bindings/net/renesas,ravb.txt
new file mode 100644
index 000000000000..1fd8831437bf
--- /dev/null
+++ b/Documentation/devicetree/bindings/net/renesas,ravb.txt
@@ -0,0 +1,48 @@
+* Renesas Electronics Ethernet AVB
+
+This file provides information on what the device node for the Ethernet AVB
+interface contains.
+
+Required properties:
+- compatible: "renesas,etheravb-r8a7790" if the device is a part of R8A7790 SoC.
+	      "renesas,etheravb-r8a7794" if the device is a part of R8A7794 SoC.
+- reg: offset and length of (1) the register block and (2) the stream buffer.
+- interrupts: interrupt specifier for the sole interrupt.
+- phy-mode: see ethernet.txt file in the same directory.
+- phy-handle: see ethernet.txt file in the same directory.
+- #address-cells: number of address cells for the MDIO bus, must be equal to 1.
+- #size-cells: number of size cells on the MDIO bus, must be equal to 0.
+- clocks: clock phandle and specifier pair.
+- pinctrl-0: phandle, referring to a default pin configuration node.
+
+Optional properties:
+- interrupt-parent: the phandle for the interrupt controller that services
+		    interrupts for this device.
+- pinctrl-names: pin configuration state name ("default").
+- renesas,no-ether-link: boolean, specify when a board does not provide a proper
+			 AVB_LINK signal.
+- renesas,ether-link-active-low: boolean, specify when the AVB_LINK signal is
+				 active-low instead of normal active-high.
+
+Example:
+
+	ethernet@e6800000 {
+		compatible = "renesas,etheravb-r8a7790";
+		reg = <0 0xe6800000 0 0x800>, <0 0xee0e8000 0 0x4000>;
+		interrupt-parent = <&gic>;
+		interrupts = <0 163 IRQ_TYPE_LEVEL_HIGH>;
+		clocks = <&mstp8_clks R8A7790_CLK_ETHERAVB>;
+		phy-mode = "rmii";
+		phy-handle = <&phy0>;
+		pinctrl-0 = <&ether_pins>;
+		pinctrl-names = "default";
+		renesas,no-ether-link;
+		#address-cells = <1>;
+		#size-cells = <0>;
+
+		phy0: ethernet-phy@0 {
+			reg = <0>;
+			interrupt-parent = <&gpio2>;
+			interrupts = <15 IRQ_TYPE_LEVEL_LOW>;
+		};
+	};
diff --git a/drivers/net/ethernet/renesas/Kconfig b/drivers/net/ethernet/renesas/Kconfig
index 196e98a2d93b..8e8031a1c6c7 100644
--- a/drivers/net/ethernet/renesas/Kconfig
+++ b/drivers/net/ethernet/renesas/Kconfig
@@ -2,6 +2,21 @@
 # Renesas device configuration
 #
 
+config NET_VENDOR_RENESAS
+	bool "Renesas devices"
+	default y
+	---help---
+	  If you have a network (Ethernet) card belonging to this class, say Y
+	  and read the Ethernet-HOWTO, available from
+	  <http://www.tldp.org/docs.html#howto>.
+
+	  Note that the answer to this question doesn't directly affect the
+	  kernel: saying N will just cause the configurator to skip all
+	  the questions about Renesas devices. If you say Y, you will be asked
+	  for your specific device in the following questions.
+
+if NET_VENDOR_RENESAS
+
 config SH_ETH
 	tristate "Renesas SuperH Ethernet support"
 	depends on HAS_DMA
@@ -15,3 +30,19 @@ config SH_ETH
 	  This driver supporting CPUs are:
 		- SH7619, SH7710, SH7712, SH7724, SH7734, SH7763, SH7757,
 		  R8A7740, R8A777x and R8A779x.
+
+config RAVB
+	tristate "Renesas Ethernet AVB support"
+	depends on HAS_DMA
+	depends on ARCH_SHMOBILE || COMPILE_TEST
+	select CRC32
+	select MII
+	select MDIO_BITBANG
+	select PHYLIB
+	select PTP_1588_CLOCK
+	help
+	  Renesas Ethernet AVB device driver.
+	  This driver supports the following SoCs:
+		- R8A779x.
+
+endif # NET_VENDOR_RENESAS
diff --git a/drivers/net/ethernet/renesas/Makefile b/drivers/net/ethernet/renesas/Makefile
index 1c278a8e066a..aa354a666fac 100644
--- a/drivers/net/ethernet/renesas/Makefile
+++ b/drivers/net/ethernet/renesas/Makefile
@@ -3,3 +3,4 @@
 #
 
 obj-$(CONFIG_SH_ETH) += sh_eth.o
+obj-$(CONFIG_RAVB) += ravb.o
diff --git a/drivers/net/ethernet/renesas/ravb.c b/drivers/net/ethernet/renesas/ravb.c
new file mode 100644
index 000000000000..1fa9be203790
--- /dev/null
+++ b/drivers/net/ethernet/renesas/ravb.c
@@ -0,0 +1,1801 @@
+/* Renesas Ethernet AVB device driver
+ *
+ * Copyright (C) 2014-2015 Renesas Electronics Corporation
+ * Copyright (C) 2015 Renesas Solutions Corp.
+ * Copyright (C) 2015 Cogent Embedded, Inc. <source@cogentembedded.com>
+ *
+ * Based on the SuperH Ethernet driver
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms and conditions of the GNU General Public License version 2,
+ * as published by the Free Software Foundation.
+ */
+
+#include <linux/cache.h>
+#include <linux/clk.h>
+#include <linux/delay.h>
+#include <linux/dma-mapping.h>
+#include <linux/err.h>
+#include <linux/etherdevice.h>
+#include <linux/ethtool.h>
+#include <linux/if_vlan.h>
+#include <linux/kernel.h>
+#include <linux/list.h>
+#include <linux/module.h>
+#include <linux/net_tstamp.h>
+#include <linux/of.h>
+#include <linux/of_device.h>
+#include <linux/of_irq.h>
+#include <linux/of_mdio.h>
+#include <linux/of_net.h>
+#include <linux/platform_device.h>
+#include <linux/pm_runtime.h>
+#include <linux/slab.h>
+#include <linux/spinlock.h>
+
+#include "ravb.h"
+
+#define RAVB_DEF_MSG_ENABLE \
+		(NETIF_MSG_LINK	  | \
+		 NETIF_MSG_TIMER  | \
+		 NETIF_MSG_RX_ERR | \
+		 NETIF_MSG_TX_ERR)
+
+static int ravb_wait(struct net_device *ndev, enum ravb_reg reg, u32 mask,
+		     u32 value)
+{
+	int i;
+
+	for (i = 0; i < 10000; i++) {
+		if ((ravb_read(ndev, reg) & mask) == value)
+			return 0;
+		udelay(10);
+	}
+	return -ETIMEDOUT;
+}
+
+static int ravb_config(struct net_device *ndev)
+{
+	int error;
+
+	/* Set config mode */
+	ravb_write(ndev, (ravb_read(ndev, CCC) & ~CCC_OPC) | CCC_OPC_CONFIG,
+		   CCC);
+	/* Check if the operating mode is changed to the config mode */
+	error = ravb_wait(ndev, CSR, CSR_OPS, CSR_OPS_CONFIG);
+	if (error)
+		netdev_err(ndev, "failed to switch device to config mode\n");
+
+	return error;
+}
+
+static void ravb_set_duplex(struct net_device *ndev)
+{
+	struct ravb_private *priv = netdev_priv(ndev);
+	u32 ecmr = ravb_read(ndev, ECMR);
+
+	if (priv->duplex)	/* Full */
+		ecmr |=  ECMR_DM;
+	else			/* Half */
+		ecmr &= ~ECMR_DM;
+	ravb_write(ndev, ecmr, ECMR);
+}
+
+static void ravb_set_rate(struct net_device *ndev)
+{
+	struct ravb_private *priv = netdev_priv(ndev);
+
+	switch (priv->speed) {
+	case 100:		/* 100BASE */
+		ravb_write(ndev, GECMR_SPEED_100, GECMR);
+		break;
+	case 1000:		/* 1000BASE */
+		ravb_write(ndev, GECMR_SPEED_1000, GECMR);
+		break;
+	default:
+		break;
+	}
+}
+
+static void ravb_set_buffer_align(struct sk_buff *skb)
+{
+	u32 reserve = (unsigned long)skb->data & (RAVB_ALIGN - 1);
+
+	if (reserve)
+		skb_reserve(skb, RAVB_ALIGN - reserve);
+}
+
+/* Get MAC address from the MAC address registers
+ *
+ * Ethernet AVB device doesn't have ROM for MAC address.
+ * This function gets the MAC address that was used by a bootloader.
+ */
+static void ravb_read_mac_address(struct net_device *ndev, const u8 *mac)
+{
+	if (mac) {
+		ether_addr_copy(ndev->dev_addr, mac);
+	} else {
+		ndev->dev_addr[0] = (ravb_read(ndev, MAHR) >> 24);
+		ndev->dev_addr[1] = (ravb_read(ndev, MAHR) >> 16) & 0xFF;
+		ndev->dev_addr[2] = (ravb_read(ndev, MAHR) >> 8) & 0xFF;
+		ndev->dev_addr[3] = (ravb_read(ndev, MAHR) >> 0) & 0xFF;
+		ndev->dev_addr[4] = (ravb_read(ndev, MALR) >> 8) & 0xFF;
+		ndev->dev_addr[5] = (ravb_read(ndev, MALR) >> 0) & 0xFF;
+	}
+}
+
+static void ravb_mdio_ctrl(struct mdiobb_ctrl *ctrl, u32 mask, int set)
+{
+	struct ravb_private *priv = container_of(ctrl, struct ravb_private,
+						 mdiobb);
+	u32 pir = ravb_read(priv->ndev, PIR);
+
+	if (set)
+		pir |=  mask;
+	else
+		pir &= ~mask;
+	ravb_write(priv->ndev, pir, PIR);
+}
+
+/* MDC pin control */
+static void ravb_set_mdc(struct mdiobb_ctrl *ctrl, int level)
+{
+	ravb_mdio_ctrl(ctrl, PIR_MDC, level);
+}
+
+/* Data I/O pin control */
+static void ravb_set_mdio_dir(struct mdiobb_ctrl *ctrl, int output)
+{
+	ravb_mdio_ctrl(ctrl, PIR_MMD, output);
+}
+
+/* Set data bit */
+static void ravb_set_mdio_data(struct mdiobb_ctrl *ctrl, int value)
+{
+	ravb_mdio_ctrl(ctrl, PIR_MDO, value);
+}
+
+/* Get data bit */
+static int ravb_get_mdio_data(struct mdiobb_ctrl *ctrl)
+{
+	struct ravb_private *priv = container_of(ctrl, struct ravb_private,
+						 mdiobb);
+
+	return (ravb_read(priv->ndev, PIR) & PIR_MDI) != 0;
+}
+
+/* MDIO bus control struct */
+static struct mdiobb_ops bb_ops = {
+	.owner = THIS_MODULE,
+	.set_mdc = ravb_set_mdc,
+	.set_mdio_dir = ravb_set_mdio_dir,
+	.set_mdio_data = ravb_set_mdio_data,
+	.get_mdio_data = ravb_get_mdio_data,
+};
+
+/* Free skb's and DMA buffers for Ethernet AVB */
+static void ravb_ring_free(struct net_device *ndev, int q)
+{
+	struct ravb_private *priv = netdev_priv(ndev);
+	int ring_size;
+	int i;
+
+	/* Free RX skb ringbuffer */
+	if (priv->rx_skb[q]) {
+		for (i = 0; i < priv->num_rx_ring[q]; i++)
+			dev_kfree_skb(priv->rx_skb[q][i]);
+	}
+	kfree(priv->rx_skb[q]);
+	priv->rx_skb[q] = NULL;
+
+	/* Free TX skb ringbuffer */
+	if (priv->tx_skb[q]) {
+		for (i = 0; i < priv->num_tx_ring[q]; i++)
+			dev_kfree_skb(priv->tx_skb[q][i]);
+	}
+	kfree(priv->tx_skb[q]);
+	priv->tx_skb[q] = NULL;
+
+	/* Free aligned TX buffers */
+	if (priv->tx_buffers[q]) {
+		for (i = 0; i < priv->num_tx_ring[q]; i++)
+			kfree(priv->tx_buffers[q][i]);
+	}
+	kfree(priv->tx_buffers[q]);
+	priv->tx_buffers[q] = NULL;
+
+	if (priv->rx_ring[q]) {
+		ring_size = sizeof(struct ravb_ex_rx_desc) *
+			    (priv->num_rx_ring[q] + 1);
+		dma_free_coherent(NULL, ring_size, priv->rx_ring[q],
+				  priv->rx_desc_dma[q]);
+		priv->rx_ring[q] = NULL;
+	}
+
+	if (priv->tx_ring[q]) {
+		ring_size = sizeof(struct ravb_tx_desc) *
+			    (priv->num_tx_ring[q] + 1);
+		dma_free_coherent(NULL, ring_size, priv->tx_ring[q],
+				  priv->tx_desc_dma[q]);
+		priv->tx_ring[q] = NULL;
+	}
+}
+
+/* Format skb and descriptor buffer for Ethernet AVB */
+static void ravb_ring_format(struct net_device *ndev, int q)
+{
+	struct ravb_private *priv = netdev_priv(ndev);
+	struct ravb_ex_rx_desc *rx_desc = NULL;
+	struct ravb_tx_desc *tx_desc = NULL;
+	struct ravb_desc *desc = NULL;
+	int rx_ring_size = sizeof(*rx_desc) * priv->num_rx_ring[q];
+	int tx_ring_size = sizeof(*tx_desc) * priv->num_tx_ring[q];
+	struct sk_buff *skb;
+	dma_addr_t dma_addr;
+	void *buffer;
+	int i;
+
+	priv->cur_rx[q] = 0;
+	priv->cur_tx[q] = 0;
+	priv->dirty_rx[q] = 0;
+	priv->dirty_tx[q] = 0;
+
+	memset(priv->rx_ring[q], 0, rx_ring_size);
+	/* Build RX ring buffer */
+	for (i = 0; i < priv->num_rx_ring[q]; i++) {
+		priv->rx_skb[q][i] = NULL;
+		skb = netdev_alloc_skb(ndev, PKT_BUF_SZ + RAVB_ALIGN - 1);
+		if (!skb)
+			break;
+		ravb_set_buffer_align(skb);
+		/* RX descriptor */
+		rx_desc = &priv->rx_ring[q][i];
+		/* The size of the buffer should be on 16-byte boundary. */
+		rx_desc->ds_cc = cpu_to_le16(ALIGN(PKT_BUF_SZ, 16));
+		dma_addr = dma_map_single(&ndev->dev, skb->data,
+					  ALIGN(PKT_BUF_SZ, 16),
+					  DMA_FROM_DEVICE);
+		if (dma_mapping_error(&ndev->dev, dma_addr)) {
+			dev_kfree_skb(skb);
+			break;
+		}
+		priv->rx_skb[q][i] = skb;
+		rx_desc->dptr = cpu_to_le32(dma_addr);
+		rx_desc->die_dt = DT_FEMPTY;
+	}
+	rx_desc = &priv->rx_ring[q][i];
+	rx_desc->dptr = cpu_to_le32((u32)priv->rx_desc_dma[q]);
+	rx_desc->die_dt = DT_LINKFIX; /* type */
+	priv->dirty_rx[q] = (u32)(i - priv->num_rx_ring[q]);
+
+	memset(priv->tx_ring[q], 0, tx_ring_size);
+	/* Build TX ring buffer */
+	for (i = 0; i < priv->num_tx_ring[q]; i++) {
+		priv->tx_skb[q][i] = NULL;
+		priv->tx_buffers[q][i] = NULL;
+		buffer = kmalloc(PKT_BUF_SZ + RAVB_ALIGN - 1, GFP_KERNEL);
+		if (!buffer)
+			break;
+		/* Aligned TX buffer */
+		priv->tx_buffers[q][i] = buffer;
+		tx_desc = &priv->tx_ring[q][i];
+		tx_desc->die_dt = DT_EEMPTY;
+	}
+	tx_desc = &priv->tx_ring[q][i];
+	tx_desc->dptr = cpu_to_le32((u32)priv->tx_desc_dma[q]);
+	tx_desc->die_dt = DT_LINKFIX; /* type */
+
+	/* RX descriptor base address for best effort */
+	desc = &priv->desc_bat[RX_QUEUE_OFFSET + q];
+	desc->die_dt = DT_LINKFIX; /* type */
+	desc->dptr = cpu_to_le32((u32)priv->rx_desc_dma[q]);
+
+	/* TX descriptor base address for best effort */
+	desc = &priv->desc_bat[q];
+	desc->die_dt = DT_LINKFIX; /* type */
+	desc->dptr = cpu_to_le32((u32)priv->tx_desc_dma[q]);
+}
+
+/* Init skb and descriptor buffer for Ethernet AVB */
+static int ravb_ring_init(struct net_device *ndev, int q)
+{
+	struct ravb_private *priv = netdev_priv(ndev);
+	int ring_size;
+
+	/* Allocate RX and TX skb rings */
+	priv->rx_skb[q] = kcalloc(priv->num_rx_ring[q],
+				  sizeof(*priv->rx_skb[q]), GFP_KERNEL);
+	priv->tx_skb[q] = kcalloc(priv->num_tx_ring[q],
+				  sizeof(*priv->tx_skb[q]), GFP_KERNEL);
+	if (!priv->rx_skb[q] || !priv->tx_skb[q])
+		goto error;
+
+	/* Allocate rings for the aligned buffers */
+	priv->tx_buffers[q] = kcalloc(priv->num_tx_ring[q],
+				      sizeof(*priv->tx_buffers[q]), GFP_KERNEL);
+	if (!priv->tx_buffers[q])
+		goto error;
+
+	/* Allocate all RX descriptors. */
+	ring_size = sizeof(struct ravb_ex_rx_desc) * (priv->num_rx_ring[q] + 1);
+	priv->rx_ring[q] = dma_alloc_coherent(NULL, ring_size,
+					      &priv->rx_desc_dma[q],
+					      GFP_KERNEL);
+	if (!priv->rx_ring[q])
+		goto error;
+
+	priv->dirty_rx[q] = 0;
+
+	/* Allocate all TX descriptors. */
+	ring_size = sizeof(struct ravb_tx_desc) * (priv->num_tx_ring[q] + 1);
+	priv->tx_ring[q] = dma_alloc_coherent(NULL, ring_size,
+					      &priv->tx_desc_dma[q],
+					      GFP_KERNEL);
+	if (!priv->tx_ring[q])
+		goto error;
+
+	return 0;
+
+error:
+	ravb_ring_free(ndev, q);
+
+	return -ENOMEM;
+}
+
+/* E-MAC init function */
+static void ravb_emac_init(struct net_device *ndev)
+{
+	struct ravb_private *priv = netdev_priv(ndev);
+	u32 ecmr;
+
+	/* Receive frame limit set register */
+	ravb_write(ndev, ndev->mtu + ETH_HLEN + VLAN_HLEN + ETH_FCS_LEN, RFLR);
+
+	/* PAUSE prohibition */
+	ecmr =  ravb_read(ndev, ECMR);
+	ecmr &= ECMR_DM;
+	ecmr |= ECMR_ZPF | (priv->duplex ? ECMR_DM : 0) | ECMR_TE | ECMR_RE;
+	ravb_write(ndev, ecmr, ECMR);
+
+	ravb_set_rate(ndev);
+
+	/* Set MAC address */
+	ravb_write(ndev,
+		   (ndev->dev_addr[0] << 24) | (ndev->dev_addr[1] << 16) |
+		   (ndev->dev_addr[2] << 8)  | (ndev->dev_addr[3]), MAHR);
+	ravb_write(ndev,
+		   (ndev->dev_addr[4] << 8)  | (ndev->dev_addr[5]), MALR);
+
+	ravb_write(ndev, 1, MPR);
+
+	/* E-MAC status register clear */
+	ravb_write(ndev, ECSR_ICD | ECSR_MPD, ECSR);
+
+	/* E-MAC interrupt enable register */
+	ravb_write(ndev, ECSIPR_ICDIP | ECSIPR_MPDIP | ECSIPR_LCHNGIP, ECSIPR);
+}
+
+/* Device init function for Ethernet AVB */
+static int ravb_dmac_init(struct net_device *ndev)
+{
+	int error;
+
+	/* Set CONFIG mode */
+	error = ravb_config(ndev);
+	if (error)
+		return error;
+
+	error = ravb_ring_init(ndev, RAVB_BE);
+	if (error)
+		return error;
+	error = ravb_ring_init(ndev, RAVB_NC);
+	if (error) {
+		ravb_ring_free(ndev, RAVB_BE);
+		return error;
+	}
+
+	/* Descriptor format */
+	ravb_ring_format(ndev, RAVB_BE);
+	ravb_ring_format(ndev, RAVB_NC);
+
+#if defined(__LITTLE_ENDIAN)
+	ravb_write(ndev, ravb_read(ndev, CCC) & ~CCC_BOC, CCC);
+#else
+	ravb_write(ndev, ravb_read(ndev, CCC) | CCC_BOC, CCC);
+#endif
+
+	/* Set AVB RX */
+	ravb_write(ndev, RCR_EFFS | RCR_ENCF | RCR_ETS0 | 0x18000000, RCR);
+
+	/* Set FIFO size */
+	ravb_write(ndev, TGC_TQP_AVBMODE1 | 0x00222200, TGC);
+
+	/* Timestamp enable */
+	ravb_write(ndev, TCCR_TFEN, TCCR);
+
+	/* Interrupt enable: */
+	/* Frame receive */
+	ravb_write(ndev, RIC0_FRE0 | RIC0_FRE1, RIC0);
+	/* Receive FIFO full warning */
+	ravb_write(ndev, RIC1_RFWE, RIC1);
+	/* Receive FIFO full error, descriptor empty */
+	ravb_write(ndev, RIC2_QFE0 | RIC2_QFE1 | RIC2_RFFE, RIC2);
+	/* Frame transmitted, timestamp FIFO updated */
+	ravb_write(ndev, TIC_FTE0 | TIC_FTE1 | TIC_TFUE, TIC);
+
+	/* Setting the control will start the AVB-DMAC process. */
+	ravb_write(ndev, (ravb_read(ndev, CCC) & ~CCC_OPC) | CCC_OPC_OPERATION,
+		   CCC);
+
+	return 0;
+}
+
+/* Free TX skb function for AVB-IP */
+static int ravb_tx_free(struct net_device *ndev, int q)
+{
+	struct ravb_private *priv = netdev_priv(ndev);
+	struct net_device_stats *stats = &priv->stats[q];
+	struct ravb_tx_desc *desc;
+	int free_num = 0;
+	int entry = 0;
+	u32 size;
+
+	for (; priv->cur_tx[q] - priv->dirty_tx[q] > 0; priv->dirty_tx[q]++) {
+		entry = priv->dirty_tx[q] % priv->num_tx_ring[q];
+		desc = &priv->tx_ring[q][entry];
+		if (desc->die_dt != DT_FEMPTY)
+			break;
+		/* Descriptor type must be checked before all other reads */
+		dma_rmb();
+		size = le16_to_cpu(desc->ds_tagl) & TX_DS;
+		/* Free the original skb. */
+		if (priv->tx_skb[q][entry]) {
+			dma_unmap_single(&ndev->dev, le32_to_cpu(desc->dptr),
+					 size, DMA_TO_DEVICE);
+			dev_kfree_skb_any(priv->tx_skb[q][entry]);
+			priv->tx_skb[q][entry] = NULL;
+			free_num++;
+		}
+		stats->tx_packets++;
+		stats->tx_bytes += size;
+		desc->die_dt = DT_EEMPTY;
+	}
+	return free_num;
+}
+
+static void ravb_get_tx_tstamp(struct net_device *ndev)
+{
+	struct ravb_private *priv = netdev_priv(ndev);
+	struct ravb_tstamp_skb *ts_skb, *ts_skb2;
+	struct skb_shared_hwtstamps shhwtstamps;
+	struct sk_buff *skb;
+	struct timespec64 ts;
+	u16 tag, tfa_tag;
+	int count;
+	u32 tfa2;
+
+	count = (ravb_read(ndev, TSR) & TSR_TFFL) >> 8;
+	while (count--) {
+		tfa2 = ravb_read(ndev, TFA2);
+		tfa_tag = (tfa2 & TFA2_TST) >> 16;
+		ts.tv_nsec = (u64)ravb_read(ndev, TFA0);
+		ts.tv_sec = ((u64)(tfa2 & TFA2_TSV) << 32) |
+			    ravb_read(ndev, TFA1);
+		memset(&shhwtstamps, 0, sizeof(shhwtstamps));
+		shhwtstamps.hwtstamp = timespec64_to_ktime(ts);
+		list_for_each_entry_safe(ts_skb, ts_skb2, &priv->ts_skb_list,
+					 list) {
+			skb = ts_skb->skb;
+			tag = ts_skb->tag;
+			list_del(&ts_skb->list);
+			kfree(ts_skb);
+			if (tag == tfa_tag) {
+				skb_tstamp_tx(skb, &shhwtstamps);
+				break;
+			}
+		}
+		ravb_write(ndev, ravb_read(ndev, TCCR) | TCCR_TFR, TCCR);
+	}
+}
+
+/* Packet receive function for Ethernet AVB */
+static bool ravb_rx(struct net_device *ndev, int *quota, int q)
+{
+	struct ravb_private *priv = netdev_priv(ndev);
+	int entry = priv->cur_rx[q] % priv->num_rx_ring[q];
+	int boguscnt = (priv->dirty_rx[q] + priv->num_rx_ring[q]) -
+			priv->cur_rx[q];
+	struct net_device_stats *stats = &priv->stats[q];
+	struct ravb_ex_rx_desc *desc;
+	struct sk_buff *skb;
+	dma_addr_t dma_addr;
+	struct timespec64 ts;
+	u16 pkt_len = 0;
+	u8  desc_status;
+	int limit;
+
+	boguscnt = min(boguscnt, *quota);
+	limit = boguscnt;
+	desc = &priv->rx_ring[q][entry];
+	while (desc->die_dt != DT_FEMPTY) {
+		/* Descriptor type must be checked before all other reads */
+		dma_rmb();
+		desc_status = desc->msc;
+		pkt_len = le16_to_cpu(desc->ds_cc) & RX_DS;
+
+		if (--boguscnt < 0)
+			break;
+
+		if (desc_status & MSC_MC)
+			stats->multicast++;
+
+		if (desc_status & (MSC_CRC | MSC_RFE | MSC_RTSF | MSC_RTLF |
+				   MSC_CEEF)) {
+			stats->rx_errors++;
+			if (desc_status & MSC_CRC)
+				stats->rx_crc_errors++;
+			if (desc_status & MSC_RFE)
+				stats->rx_frame_errors++;
+			if (desc_status & (MSC_RTLF | MSC_RTSF))
+				stats->rx_length_errors++;
+			if (desc_status & MSC_CEEF)
+				stats->rx_missed_errors++;
+		} else {
+			u32 get_ts = priv->tstamp_rx_ctrl & RAVB_RXTSTAMP_TYPE;
+
+			skb = priv->rx_skb[q][entry];
+			priv->rx_skb[q][entry] = NULL;
+			dma_sync_single_for_cpu(&ndev->dev,
+						le32_to_cpu(desc->dptr),
+						ALIGN(PKT_BUF_SZ, 16),
+						DMA_FROM_DEVICE);
+			get_ts &= (q == RAVB_NC) ?
+					RAVB_RXTSTAMP_TYPE_V2_L2_EVENT :
+					~RAVB_RXTSTAMP_TYPE_V2_L2_EVENT;
+			if (get_ts) {
+				struct skb_shared_hwtstamps *shhwtstamps;
+
+				shhwtstamps = skb_hwtstamps(skb);
+				memset(shhwtstamps, 0, sizeof(*shhwtstamps));
+				ts.tv_sec = ((u64) le16_to_cpu(desc->ts_sh) <<
+					     32) | le32_to_cpu(desc->ts_sl);
+				ts.tv_nsec = le32_to_cpu(desc->ts_n);
+				shhwtstamps->hwtstamp = timespec64_to_ktime(ts);
+			}
+			skb_put(skb, pkt_len);
+			skb->protocol = eth_type_trans(skb, ndev);
+			napi_gro_receive(&priv->napi[q], skb);
+			stats->rx_packets++;
+			stats->rx_bytes += pkt_len;
+		}
+
+		entry = (++priv->cur_rx[q]) % priv->num_rx_ring[q];
+		desc = &priv->rx_ring[q][entry];
+	}
+
+	/* Refill the RX ring buffers. */
+	for (; priv->cur_rx[q] - priv->dirty_rx[q] > 0; priv->dirty_rx[q]++) {
+		entry = priv->dirty_rx[q] % priv->num_rx_ring[q];
+		desc = &priv->rx_ring[q][entry];
+		/* The size of the buffer should be on 16-byte boundary. */
+		desc->ds_cc = cpu_to_le16(ALIGN(PKT_BUF_SZ, 16));
+
+		if (!priv->rx_skb[q][entry]) {
+			skb = netdev_alloc_skb(ndev,
+					       PKT_BUF_SZ + RAVB_ALIGN - 1);
+			if (!skb)
+				break;	/* Better luck next round. */
+			ravb_set_buffer_align(skb);
+			dma_unmap_single(&ndev->dev, le32_to_cpu(desc->dptr),
+					 ALIGN(PKT_BUF_SZ, 16),
+					 DMA_FROM_DEVICE);
+			dma_addr = dma_map_single(&ndev->dev, skb->data,
+						  le16_to_cpu(desc->ds_cc),
+						  DMA_FROM_DEVICE);
+			skb_checksum_none_assert(skb);
+			if (dma_mapping_error(&ndev->dev, dma_addr)) {
+				dev_kfree_skb_any(skb);
+				break;
+			}
+			desc->dptr = cpu_to_le32(dma_addr);
+			priv->rx_skb[q][entry] = skb;
+		}
+		/* Descriptor type must be set after all the above writes */
+		dma_wmb();
+		desc->die_dt = DT_FEMPTY;
+	}
+
+	*quota -= limit - (++boguscnt);
+
+	return boguscnt <= 0;
+}
+
+static void ravb_rcv_snd_disable(struct net_device *ndev)
+{
+	/* Disable TX and RX */
+	ravb_write(ndev, ravb_read(ndev, ECMR) & ~(ECMR_RE | ECMR_TE), ECMR);
+}
+
+static void ravb_rcv_snd_enable(struct net_device *ndev)
+{
+	/* Enable TX and RX */
+	ravb_write(ndev, ravb_read(ndev, ECMR) | ECMR_RE | ECMR_TE, ECMR);
+}
+
+/* function for waiting dma process finished */
+static int ravb_stop_dma(struct net_device *ndev)
+{
+	int error;
+
+	/* Wait for stopping the hardware TX process */
+	error = ravb_wait(ndev, TCCR,
+			  TCCR_TSRQ0 | TCCR_TSRQ1 | TCCR_TSRQ2 | TCCR_TSRQ3, 0);
+	if (error)
+		return error;
+
+	error = ravb_wait(ndev, CSR, CSR_TPO0 | CSR_TPO1 | CSR_TPO2 | CSR_TPO3,
+			  0);
+	if (error)
+		return error;
+
+	/* Stop the E-MAC's RX/TX processes. */
+	ravb_rcv_snd_disable(ndev);
+
+	/* Wait for stopping the RX DMA process */
+	error = ravb_wait(ndev, CSR, CSR_RPO, 0);
+	if (error)
+		return error;
+
+	/* Stop AVB-DMAC process */
+	return ravb_config(ndev);
+}
+
+/* E-MAC interrupt handler */
+static void ravb_emac_interrupt(struct net_device *ndev)
+{
+	struct ravb_private *priv = netdev_priv(ndev);
+	u32 ecsr, psr;
+
+	ecsr = ravb_read(ndev, ECSR);
+	ravb_write(ndev, ecsr, ECSR);	/* clear interrupt */
+	if (ecsr & ECSR_ICD)
+		ndev->stats.tx_carrier_errors++;
+	if (ecsr & ECSR_LCHNG) {
+		/* Link changed */
+		if (priv->no_avb_link)
+			return;
+		psr = ravb_read(ndev, PSR);
+		if (priv->avb_link_active_low)
+			psr ^= PSR_LMON;
+		if (!(psr & PSR_LMON)) {
+			/* DIsable RX and TX */
+			ravb_rcv_snd_disable(ndev);
+		} else {
+			/* Enable RX and TX */
+			ravb_rcv_snd_enable(ndev);
+		}
+	}
+}
+
+/* Error interrupt handler */
+static void ravb_error_interrupt(struct net_device *ndev)
+{
+	struct ravb_private *priv = netdev_priv(ndev);
+	u32 eis, ris2;
+
+	eis = ravb_read(ndev, EIS);
+	ravb_write(ndev, ~EIS_QFS, EIS);
+	if (eis & EIS_QFS) {
+		ris2 = ravb_read(ndev, RIS2);
+		ravb_write(ndev, ~(RIS2_QFF0 | RIS2_RFFF), RIS2);
+
+		/* Receive Descriptor Empty int */
+		if (ris2 & RIS2_QFF0)
+			priv->stats[RAVB_BE].rx_over_errors++;
+
+		    /* Receive Descriptor Empty int */
+		if (ris2 & RIS2_QFF1)
+			priv->stats[RAVB_NC].rx_over_errors++;
+
+		/* Receive FIFO Overflow int */
+		if (ris2 & RIS2_RFFF)
+			priv->rx_fifo_errors++;
+	}
+}
+
+static irqreturn_t ravb_interrupt(int irq, void *dev_id)
+{
+	struct net_device *ndev = dev_id;
+	struct ravb_private *priv = netdev_priv(ndev);
+	irqreturn_t result = IRQ_NONE;
+	u32 iss;
+
+	spin_lock(&priv->lock);
+	/* Get interrupt status */
+	iss = ravb_read(ndev, ISS);
+
+	/* Received and transmitted interrupts */
+	if (iss & (ISS_FRS | ISS_FTS | ISS_TFUS)) {
+		u32 ris0 = ravb_read(ndev, RIS0);
+		u32 ric0 = ravb_read(ndev, RIC0);
+		u32 tis  = ravb_read(ndev, TIS);
+		u32 tic  = ravb_read(ndev, TIC);
+		int q;
+
+		/* Timestamp updated */
+		if (tis & TIS_TFUF) {
+			ravb_write(ndev, ~TIS_TFUF, TIS);
+			ravb_get_tx_tstamp(ndev);
+			result = IRQ_HANDLED;
+		}
+
+		/* Network control and best effort queue RX/TX */
+		for (q = RAVB_NC; q >= RAVB_BE; q--) {
+			if (((ris0 & ric0) & BIT(q)) ||
+			    ((tis  & tic)  & BIT(q))) {
+				if (napi_schedule_prep(&priv->napi[q])) {
+					/* Mask RX and TX interrupts */
+					ravb_write(ndev, ric0 & ~BIT(q), RIC0);
+					ravb_write(ndev, tic  & ~BIT(q), TIC);
+					__napi_schedule(&priv->napi[q]);
+				} else {
+					netdev_warn(ndev,
+						    "ignoring interrupt, rx status 0x%08x, rx mask 0x%08x,\n",
+						    ris0, ric0);
+					netdev_warn(ndev,
+						    "                    tx status 0x%08x, tx mask 0x%08x.\n",
+						    tis, tic);
+				}
+				result = IRQ_HANDLED;
+			}
+		}
+	}
+
+	/* E-MAC status summary */
+	if (iss & ISS_MS) {
+		ravb_emac_interrupt(ndev);
+		result = IRQ_HANDLED;
+	}
+
+	/* Error status summary */
+	if (iss & ISS_ES) {
+		ravb_error_interrupt(ndev);
+		result = IRQ_HANDLED;
+	}
+
+	mmiowb();
+	spin_unlock(&priv->lock);
+	return result;
+}
+
+static int ravb_poll(struct napi_struct *napi, int budget)
+{
+	struct net_device *ndev = napi->dev;
+	struct ravb_private *priv = netdev_priv(ndev);
+	unsigned long flags;
+	int q = napi - priv->napi;
+	int mask = BIT(q);
+	int quota = budget;
+	u32 ris0, tis;
+
+	for (;;) {
+		tis = ravb_read(ndev, TIS);
+		ris0 = ravb_read(ndev, RIS0);
+		if (!((ris0 & mask) || (tis & mask)))
+			break;
+
+		/* Processing RX Descriptor Ring */
+		if (ris0 & mask) {
+			/* Clear RX interrupt */
+			ravb_write(ndev, ~mask, RIS0);
+			if (ravb_rx(ndev, &quota, q))
+				goto out;
+		}
+		/* Processing TX Descriptor Ring */
+		if (tis & mask) {
+			spin_lock_irqsave(&priv->lock, flags);
+			/* Clear TX interrupt */
+			ravb_write(ndev, ~mask, TIS);
+			ravb_tx_free(ndev, q);
+			netif_wake_subqueue(ndev, q);
+			mmiowb();
+			spin_unlock_irqrestore(&priv->lock, flags);
+		}
+	}
+
+	napi_complete(napi);
+
+	/* Re-enable RX/TX interrupts */
+	spin_lock_irqsave(&priv->lock, flags);
+	ravb_write(ndev, ravb_read(ndev, RIC0) | mask, RIC0);
+	ravb_write(ndev, ravb_read(ndev, TIC)  | mask,  TIC);
+	mmiowb();
+	spin_unlock_irqrestore(&priv->lock, flags);
+
+	/* Receive error message handling */
+	priv->rx_over_errors =  priv->stats[RAVB_BE].rx_over_errors;
+	priv->rx_over_errors += priv->stats[RAVB_NC].rx_over_errors;
+	if (priv->rx_over_errors != ndev->stats.rx_over_errors) {
+		ndev->stats.rx_over_errors = priv->rx_over_errors;
+		netif_err(priv, rx_err, ndev, "Receive Descriptor Empty\n");
+	}
+	if (priv->rx_fifo_errors != ndev->stats.rx_fifo_errors) {
+		ndev->stats.rx_fifo_errors = priv->rx_fifo_errors;
+		netif_err(priv, rx_err, ndev, "Receive FIFO Overflow\n");
+	}
+out:
+	return budget - quota;
+}
+
+/* PHY state control function */
+static void ravb_adjust_link(struct net_device *ndev)
+{
+	struct ravb_private *priv = netdev_priv(ndev);
+	struct phy_device *phydev = priv->phydev;
+	bool new_state = false;
+
+	if (phydev->link) {
+		if (phydev->duplex != priv->duplex) {
+			new_state = true;
+			priv->duplex = phydev->duplex;
+			ravb_set_duplex(ndev);
+		}
+
+		if (phydev->speed != priv->speed) {
+			new_state = true;
+			priv->speed = phydev->speed;
+			ravb_set_rate(ndev);
+		}
+		if (!priv->link) {
+			ravb_write(ndev, ravb_read(ndev, ECMR) & ~ECMR_TXF,
+				   ECMR);
+			new_state = true;
+			priv->link = phydev->link;
+			if (priv->no_avb_link)
+				ravb_rcv_snd_enable(ndev);
+		}
+	} else if (priv->link) {
+		new_state = true;
+		priv->link = 0;
+		priv->speed = 0;
+		priv->duplex = -1;
+		if (priv->no_avb_link)
+			ravb_rcv_snd_disable(ndev);
+	}
+
+	if (new_state && netif_msg_link(priv))
+		phy_print_status(phydev);
+}
+
+/* PHY init function */
+static int ravb_phy_init(struct net_device *ndev)
+{
+	struct device_node *np = ndev->dev.parent->of_node;
+	struct ravb_private *priv = netdev_priv(ndev);
+	struct phy_device *phydev;
+	struct device_node *pn;
+
+	priv->link = 0;
+	priv->speed = 0;
+	priv->duplex = -1;
+
+	/* Try connecting to PHY */
+	pn = of_parse_phandle(np, "phy-handle", 0);
+	phydev = of_phy_connect(ndev, pn, ravb_adjust_link, 0,
+				priv->phy_interface);
+	if (!phydev) {
+		netdev_err(ndev, "failed to connect PHY\n");
+		return -ENOENT;
+	}
+
+	netdev_info(ndev, "attached PHY %d (IRQ %d) to driver %s\n",
+		    phydev->addr, phydev->irq, phydev->drv->name);
+
+	priv->phydev = phydev;
+
+	return 0;
+}
+
+/* PHY control start function */
+static int ravb_phy_start(struct net_device *ndev)
+{
+	struct ravb_private *priv = netdev_priv(ndev);
+	int error;
+
+	error = ravb_phy_init(ndev);
+	if (error)
+		return error;
+
+	phy_start(priv->phydev);
+
+	return 0;
+}
+
+static int ravb_get_settings(struct net_device *ndev, struct ethtool_cmd *ecmd)
+{
+	struct ravb_private *priv = netdev_priv(ndev);
+	int error = -ENODEV;
+	unsigned long flags;
+
+	if (priv->phydev) {
+		spin_lock_irqsave(&priv->lock, flags);
+		error = phy_ethtool_gset(priv->phydev, ecmd);
+		spin_unlock_irqrestore(&priv->lock, flags);
+	}
+
+	return error;
+}
+
+static int ravb_set_settings(struct net_device *ndev, struct ethtool_cmd *ecmd)
+{
+	struct ravb_private *priv = netdev_priv(ndev);
+	unsigned long flags;
+	int error;
+
+	if (!priv->phydev)
+		return -ENODEV;
+
+	spin_lock_irqsave(&priv->lock, flags);
+
+	/* Disable TX and RX */
+	ravb_rcv_snd_disable(ndev);
+
+	error = phy_ethtool_sset(priv->phydev, ecmd);
+	if (error)
+		goto error_exit;
+
+	if (ecmd->duplex == DUPLEX_FULL)
+		priv->duplex = 1;
+	else
+		priv->duplex = 0;
+
+	ravb_set_duplex(ndev);
+
+error_exit:
+	mdelay(1);
+
+	/* Enable TX and RX */
+	ravb_rcv_snd_enable(ndev);
+
+	mmiowb();
+	spin_unlock_irqrestore(&priv->lock, flags);
+
+	return error;
+}
+
+static int ravb_nway_reset(struct net_device *ndev)
+{
+	struct ravb_private *priv = netdev_priv(ndev);
+	int error = -ENODEV;
+	unsigned long flags;
+
+	if (priv->phydev) {
+		spin_lock_irqsave(&priv->lock, flags);
+		error = phy_start_aneg(priv->phydev);
+		spin_unlock_irqrestore(&priv->lock, flags);
+	}
+
+	return error;
+}
+
+static u32 ravb_get_msglevel(struct net_device *ndev)
+{
+	struct ravb_private *priv = netdev_priv(ndev);
+
+	return priv->msg_enable;
+}
+
+static void ravb_set_msglevel(struct net_device *ndev, u32 value)
+{
+	struct ravb_private *priv = netdev_priv(ndev);
+
+	priv->msg_enable = value;
+}
+
+static const char ravb_gstrings_stats[][ETH_GSTRING_LEN] = {
+	"rx_queue_0_current",
+	"tx_queue_0_current",
+	"rx_queue_0_dirty",
+	"tx_queue_0_dirty",
+	"rx_queue_0_packets",
+	"tx_queue_0_packets",
+	"rx_queue_0_bytes",
+	"tx_queue_0_bytes",
+	"rx_queue_0_mcast_packets",
+	"rx_queue_0_errors",
+	"rx_queue_0_crc_errors",
+	"rx_queue_0_frame_errors",
+	"rx_queue_0_length_errors",
+	"rx_queue_0_missed_errors",