--- /dev/null
+/*
+ * Xilinx EmacLite Linux driver for the Xilinx Ethernet MAC Lite device.
+ *
+ * This is a new flat driver which is based on the original emac_lite
+ * driver from John Williams <john.williams@xilinx.com>.
+ *
+ * 2007 - 2013 (c) Xilinx, Inc.
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License as published by the
+ * Free Software Foundation; either version 2 of the License, or (at your
+ * option) any later version.
+ */
+
+#include <linux/module.h>
+#include <linux/uaccess.h>
+#include <linux/netdevice.h>
+#include <linux/etherdevice.h>
+#include <linux/skbuff.h>
+#include <linux/io.h>
+#include <linux/slab.h>
+#include <linux/of_address.h>
+#include <linux/of_device.h>
+#include <linux/of_platform.h>
+#include <linux/of_mdio.h>
+#include <linux/of_net.h>
+#include <linux/phy.h>
+#include <linux/interrupt.h>
+
+#define DRIVER_NAME "xilinx_emaclite"
+
+/* Register offsets for the EmacLite Core */
+#define XEL_TXBUFF_OFFSET 0x0 /* Transmit Buffer */
+#define XEL_MDIOADDR_OFFSET 0x07E4 /* MDIO Address Register */
+#define XEL_MDIOWR_OFFSET 0x07E8 /* MDIO Write Data Register */
+#define XEL_MDIORD_OFFSET 0x07EC /* MDIO Read Data Register */
+#define XEL_MDIOCTRL_OFFSET 0x07F0 /* MDIO Control Register */
+#define XEL_GIER_OFFSET 0x07F8 /* GIE Register */
+#define XEL_TSR_OFFSET 0x07FC /* Tx status */
+#define XEL_TPLR_OFFSET 0x07F4 /* Tx packet length */
+
+#define XEL_RXBUFF_OFFSET 0x1000 /* Receive Buffer */
+#define XEL_RPLR_OFFSET 0x100C /* Rx packet length */
+#define XEL_RSR_OFFSET 0x17FC /* Rx status */
+
+#define XEL_BUFFER_OFFSET 0x0800 /* Next Tx/Rx buffer's offset */
+
+/* MDIO Address Register Bit Masks */
+#define XEL_MDIOADDR_REGADR_MASK 0x0000001F /* Register Address */
+#define XEL_MDIOADDR_PHYADR_MASK 0x000003E0 /* PHY Address */
+#define XEL_MDIOADDR_PHYADR_SHIFT 5
+#define XEL_MDIOADDR_OP_MASK 0x00000400 /* RD/WR Operation */
+
+/* MDIO Write Data Register Bit Masks */
+#define XEL_MDIOWR_WRDATA_MASK 0x0000FFFF /* Data to be Written */
+
+/* MDIO Read Data Register Bit Masks */
+#define XEL_MDIORD_RDDATA_MASK 0x0000FFFF /* Data to be Read */
+
+/* MDIO Control Register Bit Masks */
+#define XEL_MDIOCTRL_MDIOSTS_MASK 0x00000001 /* MDIO Status Mask */
+#define XEL_MDIOCTRL_MDIOEN_MASK 0x00000008 /* MDIO Enable */
+
+/* Global Interrupt Enable Register (GIER) Bit Masks */
+#define XEL_GIER_GIE_MASK 0x80000000 /* Global Enable */
+
+/* Transmit Status Register (TSR) Bit Masks */
+#define XEL_TSR_XMIT_BUSY_MASK 0x00000001 /* Tx complete */
+#define XEL_TSR_PROGRAM_MASK 0x00000002 /* Program the MAC address */
+#define XEL_TSR_XMIT_IE_MASK 0x00000008 /* Tx interrupt enable bit */
+#define XEL_TSR_XMIT_ACTIVE_MASK 0x80000000 /* Buffer is active, SW bit
+ * only. This is not documented
+ * in the HW spec */
+
+/* Define for programming the MAC address into the EmacLite */
+#define XEL_TSR_PROG_MAC_ADDR (XEL_TSR_XMIT_BUSY_MASK | XEL_TSR_PROGRAM_MASK)
+
+/* Receive Status Register (RSR) */
+#define XEL_RSR_RECV_DONE_MASK 0x00000001 /* Rx complete */
+#define XEL_RSR_RECV_IE_MASK 0x00000008 /* Rx interrupt enable bit */
+
+/* Transmit Packet Length Register (TPLR) */
+#define XEL_TPLR_LENGTH_MASK 0x0000FFFF /* Tx packet length */
+
+/* Receive Packet Length Register (RPLR) */
+#define XEL_RPLR_LENGTH_MASK 0x0000FFFF /* Rx packet length */
+
+#define XEL_HEADER_OFFSET 12 /* Offset to length field */
+#define XEL_HEADER_SHIFT 16 /* Shift value for length */
+
+/* General Ethernet Definitions */
+#define XEL_ARP_PACKET_SIZE 28 /* Max ARP packet size */
+#define XEL_HEADER_IP_LENGTH_OFFSET 16 /* IP Length Offset */
+
+
+
+#define TX_TIMEOUT (60*HZ) /* Tx timeout is 60 seconds. */
+#define ALIGNMENT 4
+
+/* BUFFER_ALIGN(adr) calculates the number of bytes to the next alignment. */
+#define BUFFER_ALIGN(adr) ((ALIGNMENT - ((u32) adr)) % ALIGNMENT)
+
+/**
+ * struct net_local - Our private per device data
+ * @ndev: instance of the network device
+ * @tx_ping_pong: indicates whether Tx Pong buffer is configured in HW
+ * @rx_ping_pong: indicates whether Rx Pong buffer is configured in HW
+ * @next_tx_buf_to_use: next Tx buffer to write to
+ * @next_rx_buf_to_use: next Rx buffer to read from
+ * @base_addr: base address of the Emaclite device
+ * @reset_lock: lock used for synchronization
+ * @deferred_skb: holds an skb (for transmission at a later time) when the
+ * Tx buffer is not free
+ * @phy_dev: pointer to the PHY device
+ * @phy_node: pointer to the PHY device node
+ * @mii_bus: pointer to the MII bus
+ * @mdio_irqs: IRQs table for MDIO bus
+ * @last_link: last link status
+ * @has_mdio: indicates whether MDIO is included in the HW
+ */
+struct net_local {
+
+ struct net_device *ndev;
+
+ bool tx_ping_pong;
+ bool rx_ping_pong;
+ u32 next_tx_buf_to_use;
+ u32 next_rx_buf_to_use;
+ void __iomem *base_addr;
+
+ spinlock_t reset_lock;
+ struct sk_buff *deferred_skb;
+
+ struct phy_device *phy_dev;
+ struct device_node *phy_node;
+
+ struct mii_bus *mii_bus;
+ int mdio_irqs[PHY_MAX_ADDR];
+
+ int last_link;
+ bool has_mdio;
+};
+
+
+/*************************/
+/* EmacLite driver calls */
+/*************************/
+
+/**
+ * xemaclite_enable_interrupts - Enable the interrupts for the EmacLite device
+ * @drvdata: Pointer to the Emaclite device private data
+ *
+ * This function enables the Tx and Rx interrupts for the Emaclite device along
+ * with the Global Interrupt Enable.
+ */
+static void xemaclite_enable_interrupts(struct net_local *drvdata)
+{
+ u32 reg_data;
+
+ /* Enable the Tx interrupts for the first Buffer */
+ reg_data = __raw_readl(drvdata->base_addr + XEL_TSR_OFFSET);
+ __raw_writel(reg_data | XEL_TSR_XMIT_IE_MASK,
+ drvdata->base_addr + XEL_TSR_OFFSET);
+
+ /* Enable the Rx interrupts for the first buffer */
+ __raw_writel(XEL_RSR_RECV_IE_MASK, drvdata->base_addr + XEL_RSR_OFFSET);
+
+ /* Enable the Global Interrupt Enable */
+ __raw_writel(XEL_GIER_GIE_MASK, drvdata->base_addr + XEL_GIER_OFFSET);
+}
+
+/**
+ * xemaclite_disable_interrupts - Disable the interrupts for the EmacLite device
+ * @drvdata: Pointer to the Emaclite device private data
+ *
+ * This function disables the Tx and Rx interrupts for the Emaclite device,
+ * along with the Global Interrupt Enable.
+ */
+static void xemaclite_disable_interrupts(struct net_local *drvdata)
+{
+ u32 reg_data;
+
+ /* Disable the Global Interrupt Enable */
+ __raw_writel(XEL_GIER_GIE_MASK, drvdata->base_addr + XEL_GIER_OFFSET);
+
+ /* Disable the Tx interrupts for the first buffer */
+ reg_data = __raw_readl(drvdata->base_addr + XEL_TSR_OFFSET);
+ __raw_writel(reg_data & (~XEL_TSR_XMIT_IE_MASK),
+ drvdata->base_addr + XEL_TSR_OFFSET);
+
+ /* Disable the Rx interrupts for the first buffer */
+ reg_data = __raw_readl(drvdata->base_addr + XEL_RSR_OFFSET);
+ __raw_writel(reg_data & (~XEL_RSR_RECV_IE_MASK),
+ drvdata->base_addr + XEL_RSR_OFFSET);
+}
+
+/**
+ * xemaclite_aligned_write - Write from 16-bit aligned to 32-bit aligned address
+ * @src_ptr: Void pointer to the 16-bit aligned source address
+ * @dest_ptr: Pointer to the 32-bit aligned destination address
+ * @length: Number bytes to write from source to destination
+ *
+ * This function writes data from a 16-bit aligned buffer to a 32-bit aligned
+ * address in the EmacLite device.
+ */
+static void xemaclite_aligned_write(void *src_ptr, u32 *dest_ptr,
+ unsigned length)
+{
+ u32 align_buffer;
+ u32 *to_u32_ptr;
+ u16 *from_u16_ptr, *to_u16_ptr;
+
+ to_u32_ptr = dest_ptr;
+ from_u16_ptr = src_ptr;
+ align_buffer = 0;
+
+ for (; length > 3; length -= 4) {
+ to_u16_ptr = (u16 *)&align_buffer;
+ *to_u16_ptr++ = *from_u16_ptr++;
+ *to_u16_ptr++ = *from_u16_ptr++;
+
+ /* This barrier resolves occasional issues seen around
+ * cases where the data is not properly flushed out
+ * from the processor store buffers to the destination
+ * memory locations.
+ */
+ wmb();
+
+ /* Output a word */
+ *to_u32_ptr++ = align_buffer;
+ }
+ if (length) {
+ u8 *from_u8_ptr, *to_u8_ptr;
+
+ /* Set up to output the remaining data */
+ align_buffer = 0;
+ to_u8_ptr = (u8 *) &align_buffer;
+ from_u8_ptr = (u8 *) from_u16_ptr;
+
+ /* Output the remaining data */
+ for (; length > 0; length--)
+ *to_u8_ptr++ = *from_u8_ptr++;
+
+ /* This barrier resolves occasional issues seen around
+ * cases where the data is not properly flushed out
+ * from the processor store buffers to the destination
+ * memory locations.
+ */
+ wmb();
+ *to_u32_ptr = align_buffer;
+ }
+}
+
+/**
+ * xemaclite_aligned_read - Read from 32-bit aligned to 16-bit aligned buffer
+ * @src_ptr: Pointer to the 32-bit aligned source address
+ * @dest_ptr: Pointer to the 16-bit aligned destination address
+ * @length: Number bytes to read from source to destination
+ *
+ * This function reads data from a 32-bit aligned address in the EmacLite device
+ * to a 16-bit aligned buffer.
+ */
+static void xemaclite_aligned_read(u32 *src_ptr, u8 *dest_ptr,
+ unsigned length)
+{
+ u16 *to_u16_ptr, *from_u16_ptr;
+ u32 *from_u32_ptr;
+ u32 align_buffer;
+
+ from_u32_ptr = src_ptr;
+ to_u16_ptr = (u16 *) dest_ptr;
+
+ for (; length > 3; length -= 4) {
+ /* Copy each word into the temporary buffer */
+ align_buffer = *from_u32_ptr++;
+ from_u16_ptr = (u16 *)&align_buffer;
+
+ /* Read data from source */
+ *to_u16_ptr++ = *from_u16_ptr++;
+ *to_u16_ptr++ = *from_u16_ptr++;
+ }
+
+ if (length) {
+ u8 *to_u8_ptr, *from_u8_ptr;
+
+ /* Set up to read the remaining data */
+ to_u8_ptr = (u8 *) to_u16_ptr;
+ align_buffer = *from_u32_ptr++;
+ from_u8_ptr = (u8 *) &align_buffer;
+
+ /* Read the remaining data */
+ for (; length > 0; length--)
+ *to_u8_ptr = *from_u8_ptr;
+ }
+}
+
+/**
+ * xemaclite_send_data - Send an Ethernet frame
+ * @drvdata: Pointer to the Emaclite device private data
+ * @data: Pointer to the data to be sent
+ * @byte_count: Total frame size, including header
+ *
+ * This function checks if the Tx buffer of the Emaclite device is free to send
+ * data. If so, it fills the Tx buffer with data for transmission. Otherwise, it
+ * returns an error.
+ *
+ * Return: 0 upon success or -1 if the buffer(s) are full.
+ *
+ * Note: The maximum Tx packet size can not be more than Ethernet header
+ * (14 Bytes) + Maximum MTU (1500 bytes). This is excluding FCS.
+ */
+static int xemaclite_send_data(struct net_local *drvdata, u8 *data,
+ unsigned int byte_count)
+{
+ u32 reg_data;
+ void __iomem *addr;
+
+ /* Determine the expected Tx buffer address */
+ addr = drvdata->base_addr + drvdata->next_tx_buf_to_use;
+
+ /* If the length is too large, truncate it */
+ if (byte_count > ETH_FRAME_LEN)
+ byte_count = ETH_FRAME_LEN;
+
+ /* Check if the expected buffer is available */
+ reg_data = __raw_readl(addr + XEL_TSR_OFFSET);
+ if ((reg_data & (XEL_TSR_XMIT_BUSY_MASK |
+ XEL_TSR_XMIT_ACTIVE_MASK)) == 0) {
+
+ /* Switch to next buffer if configured */
+ if (drvdata->tx_ping_pong != 0)
+ drvdata->next_tx_buf_to_use ^= XEL_BUFFER_OFFSET;
+ } else if (drvdata->tx_ping_pong != 0) {
+ /* If the expected buffer is full, try the other buffer,
+ * if it is configured in HW */
+
+ addr = (void __iomem __force *)((u32 __force)addr ^
+ XEL_BUFFER_OFFSET);
+ reg_data = __raw_readl(addr + XEL_TSR_OFFSET);
+
+ if ((reg_data & (XEL_TSR_XMIT_BUSY_MASK |
+ XEL_TSR_XMIT_ACTIVE_MASK)) != 0)
+ return -1; /* Buffers were full, return failure */
+ } else
+ return -1; /* Buffer was full, return failure */
+
+ /* Write the frame to the buffer */
+ xemaclite_aligned_write(data, (u32 __force *) addr, byte_count);
+
+ __raw_writel((byte_count & XEL_TPLR_LENGTH_MASK),
+ addr + XEL_TPLR_OFFSET);
+
+ /* Update the Tx Status Register to indicate that there is a
+ * frame to send. Set the XEL_TSR_XMIT_ACTIVE_MASK flag which
+ * is used by the interrupt handler to check whether a frame
+ * has been transmitted */
+ reg_data = __raw_readl(addr + XEL_TSR_OFFSET);
+ reg_data |= (XEL_TSR_XMIT_BUSY_MASK | XEL_TSR_XMIT_ACTIVE_MASK);
+ __raw_writel(reg_data, addr + XEL_TSR_OFFSET);
+
+ return 0;
+}
+
+/**
+ * xemaclite_recv_data - Receive a frame
+ * @drvdata: Pointer to the Emaclite device private data
+ * @data: Address where the data is to be received
+ *
+ * This function is intended to be called from the interrupt context or
+ * with a wrapper which waits for the receive frame to be available.
+ *
+ * Return: Total number of bytes received
+ */
+static u16 xemaclite_recv_data(struct net_local *drvdata, u8 *data)
+{
+ void __iomem *addr;
+ u16 length, proto_type;
+ u32 reg_data;
+
+ /* Determine the expected buffer address */
+ addr = (drvdata->base_addr + drvdata->next_rx_buf_to_use);
+
+ /* Verify which buffer has valid data */
+ reg_data = __raw_readl(addr + XEL_RSR_OFFSET);
+
+ if ((reg_data & XEL_RSR_RECV_DONE_MASK) == XEL_RSR_RECV_DONE_MASK) {
+ if (drvdata->rx_ping_pong != 0)
+ drvdata->next_rx_buf_to_use ^= XEL_BUFFER_OFFSET;
+ } else {
+ /* The instance is out of sync, try other buffer if other
+ * buffer is configured, return 0 otherwise. If the instance is
+ * out of sync, do not update the 'next_rx_buf_to_use' since it
+ * will correct on subsequent calls */
+ if (drvdata->rx_ping_pong != 0)
+ addr = (void __iomem __force *)((u32 __force)addr ^
+ XEL_BUFFER_OFFSET);
+ else
+ return 0; /* No data was available */
+
+ /* Verify that buffer has valid data */
+ reg_data = __raw_readl(addr + XEL_RSR_OFFSET);
+ if ((reg_data & XEL_RSR_RECV_DONE_MASK) !=
+ XEL_RSR_RECV_DONE_MASK)
+ return 0; /* No data was available */
+ }
+
+ /* Get the protocol type of the ethernet frame that arrived */
+ proto_type = ((ntohl(__raw_readl(addr + XEL_HEADER_OFFSET +
+ XEL_RXBUFF_OFFSET)) >> XEL_HEADER_SHIFT) &
+ XEL_RPLR_LENGTH_MASK);
+
+ /* Check if received ethernet frame is a raw ethernet frame
+ * or an IP packet or an ARP packet */
+ if (proto_type > (ETH_FRAME_LEN + ETH_FCS_LEN)) {
+
+ if (proto_type == ETH_P_IP) {
+ length = ((ntohl(__raw_readl(addr +
+ XEL_HEADER_IP_LENGTH_OFFSET +
+ XEL_RXBUFF_OFFSET)) >>
+ XEL_HEADER_SHIFT) &
+ XEL_RPLR_LENGTH_MASK);
+ length += ETH_HLEN + ETH_FCS_LEN;
+
+ } else if (proto_type == ETH_P_ARP)
+ length = XEL_ARP_PACKET_SIZE + ETH_HLEN + ETH_FCS_LEN;
+ else
+ /* Field contains type other than IP or ARP, use max
+ * frame size and let user parse it */
+ length = ETH_FRAME_LEN + ETH_FCS_LEN;
+ } else
+ /* Use the length in the frame, plus the header and trailer */
+ length = proto_type + ETH_HLEN + ETH_FCS_LEN;
+
+ /* Read from the EmacLite device */
+ xemaclite_aligned_read((u32 __force *) (addr + XEL_RXBUFF_OFFSET),
+ data, length);
+
+ /* Acknowledge the frame */
+ reg_data = __raw_readl(addr + XEL_RSR_OFFSET);
+ reg_data &= ~XEL_RSR_RECV_DONE_MASK;
+ __raw_writel(reg_data, addr + XEL_RSR_OFFSET);
+
+ return length;
+}
+
+/**
+ * xemaclite_update_address - Update the MAC address in the device
+ * @drvdata: Pointer to the Emaclite device private data
+ * @address_ptr:Pointer to the MAC address (MAC address is a 48-bit value)
+ *
+ * Tx must be idle and Rx should be idle for deterministic results.
+ * It is recommended that this function should be called after the
+ * initialization and before transmission of any packets from the device.
+ * The MAC address can be programmed using any of the two transmit
+ * buffers (if configured).
+ */
+static void xemaclite_update_address(struct net_local *drvdata,
+ u8 *address_ptr)
+{
+ void __iomem *addr;
+ u32 reg_data;
+
+ /* Determine the expected Tx buffer address */
+ addr = drvdata->base_addr + drvdata->next_tx_buf_to_use;
+
+ xemaclite_aligned_write(address_ptr, (u32 __force *) addr, ETH_ALEN);
+
+ __raw_writel(ETH_ALEN, addr + XEL_TPLR_OFFSET);
+
+ /* Update the MAC address in the EmacLite */
+ reg_data = __raw_readl(addr + XEL_TSR_OFFSET);
+ __raw_writel(reg_data | XEL_TSR_PROG_MAC_ADDR, addr + XEL_TSR_OFFSET);
+
+ /* Wait for EmacLite to finish with the MAC address update */
+ while ((__raw_readl(addr + XEL_TSR_OFFSET) &
+ XEL_TSR_PROG_MAC_ADDR) != 0)
+ ;
+}
+
+/**
+ * xemaclite_set_mac_address - Set the MAC address for this device
+ * @dev: Pointer to the network device instance
+ * @addr: Void pointer to the sockaddr structure
+ *
+ * This function copies the HW address from the sockaddr strucutre to the
+ * net_device structure and updates the address in HW.
+ *
+ * Return: Error if the net device is busy or 0 if the addr is set
+ * successfully
+ */
+static int xemaclite_set_mac_address(struct net_device *dev, void *address)
+{
+ struct net_local *lp = netdev_priv(dev);
+ struct sockaddr *addr = address;
+
+ if (netif_running(dev))
+ return -EBUSY;
+
+ memcpy(dev->dev_addr, addr->sa_data, dev->addr_len);
+ xemaclite_update_address(lp, dev->dev_addr);
+ return 0;
+}
+
+/**
+ * xemaclite_tx_timeout - Callback for Tx Timeout
+ * @dev: Pointer to the network device
+ *
+ * This function is called when Tx time out occurs for Emaclite device.
+ */
+static void xemaclite_tx_timeout(struct net_device *dev)
+{
+ struct net_local *lp = netdev_priv(dev);
+ unsigned long flags;
+
+ dev_err(&lp->ndev->dev, "Exceeded transmit timeout of %lu ms\n",
+ TX_TIMEOUT * 1000UL / HZ);
+
+ dev->stats.tx_errors++;
+
+ /* Reset the device */
+ spin_lock_irqsave(&lp->reset_lock, flags);
+
+ /* Shouldn't really be necessary, but shouldn't hurt */
+ netif_stop_queue(dev);
+
+ xemaclite_disable_interrupts(lp);
+ xemaclite_enable_interrupts(lp);
+
+ if (lp->deferred_skb) {
+ dev_kfree_skb(lp->deferred_skb);
+ lp->deferred_skb = NULL;
+ dev->stats.tx_errors++;
+ }
+
+ /* To exclude tx timeout */
+ dev->trans_start = jiffies; /* prevent tx timeout */
+
+ /* We're all ready to go. Start the queue */
+ netif_wake_queue(dev);
+ spin_unlock_irqrestore(&lp->reset_lock, flags);
+}
+
+/**********************/
+/* Interrupt Handlers */
+/**********************/
+
+/**
+ * xemaclite_tx_handler - Interrupt handler for frames sent
+ * @dev: Pointer to the network device
+ *
+ * This function updates the number of packets transmitted and handles the
+ * deferred skb, if there is one.
+ */
+static void xemaclite_tx_handler(struct net_device *dev)
+{
+ struct net_local *lp = netdev_priv(dev);
+
+ dev->stats.tx_packets++;
+ if (lp->deferred_skb) {
+ if (xemaclite_send_data(lp,
+ (u8 *) lp->deferred_skb->data,
+ lp->deferred_skb->len) != 0)
+ return;
+ else {
+ dev->stats.tx_bytes += lp->deferred_skb->len;
+ dev_kfree_skb_irq(lp->deferred_skb);
+ lp->deferred_skb = NULL;
+ dev->trans_start = jiffies; /* prevent tx timeout */
+ netif_wake_queue(dev);
+ }
+ }
+}
+
+/**
+ * xemaclite_rx_handler- Interrupt handler for frames received
+ * @dev: Pointer to the network device
+ *
+ * This function allocates memory for a socket buffer, fills it with data
+ * received and hands it over to the TCP/IP stack.
+ */
+static void xemaclite_rx_handler(struct net_device *dev)
+{
+ struct net_local *lp = netdev_priv(dev);
+ struct sk_buff *skb;
+ unsigned int align;
+ u32 len;
+
+ len = ETH_FRAME_LEN + ETH_FCS_LEN;
+ skb = netdev_alloc_skb(dev, len + ALIGNMENT);
+ if (!skb) {
+ /* Couldn't get memory. */
+ dev->stats.rx_dropped++;
+ dev_err(&lp->ndev->dev, "Could not allocate receive buffer\n");
+ return;
+ }
+
+ /*
+ * A new skb should have the data halfword aligned, but this code is
+ * here just in case that isn't true. Calculate how many
+ * bytes we should reserve to get the data to start on a word
+ * boundary */
+ align = BUFFER_ALIGN(skb->data);
+ if (align)
+ skb_reserve(skb, align);
+
+ skb_reserve(skb, 2);
+
+ len = xemaclite_recv_data(lp, (u8 *) skb->data);
+
+ if (!len) {
+ dev->stats.rx_errors++;
+ dev_kfree_skb_irq(skb);
+ return;
+ }
+
+ skb_put(skb, len); /* Tell the skb how much data we got */
+
+ skb->protocol = eth_type_trans(skb, dev);
+ skb_checksum_none_assert(skb);
+
+ dev->stats.rx_packets++;
+ dev->stats.rx_bytes += len;
+
+ if (!skb_defer_rx_timestamp(skb))
+ netif_rx(skb); /* Send the packet upstream */
+}
+
+/**
+ * xemaclite_interrupt - Interrupt handler for this driver
+ * @irq: Irq of the Emaclite device
+ * @dev_id: Void pointer to the network device instance used as callback
+ * reference
+ *
+ * This function handles the Tx and Rx interrupts of the EmacLite device.
+ */
+static irqreturn_t xemaclite_interrupt(int irq, void *dev_id)
+{
+ bool tx_complete = false;
+ struct net_device *dev = dev_id;
+ struct net_local *lp = netdev_priv(dev);
+ void __iomem *base_addr = lp->base_addr;
+ u32 tx_status;
+
+ /* Check if there is Rx Data available */
+ if ((__raw_readl(base_addr + XEL_RSR_OFFSET) &
+ XEL_RSR_RECV_DONE_MASK) ||
+ (__raw_readl(base_addr + XEL_BUFFER_OFFSET + XEL_RSR_OFFSET)
+ & XEL_RSR_RECV_DONE_MASK))
+
+ xemaclite_rx_handler(dev);
+
+ /* Check if the Transmission for the first buffer is completed */
+ tx_status = __raw_readl(base_addr + XEL_TSR_OFFSET);
+ if (((tx_status & XEL_TSR_XMIT_BUSY_MASK) == 0) &&
+ (tx_status & XEL_TSR_XMIT_ACTIVE_MASK) != 0) {
+
+ tx_status &= ~XEL_TSR_XMIT_ACTIVE_MASK;
+ __raw_writel(tx_status, base_addr + XEL_TSR_OFFSET);
+
+ tx_complete = true;
+ }
+
+ /* Check if the Transmission for the second buffer is completed */
+ tx_status = __raw_readl(base_addr + XEL_BUFFER_OFFSET + XEL_TSR_OFFSET);
+ if (((tx_status & XEL_TSR_XMIT_BUSY_MASK) == 0) &&
+ (tx_status & XEL_TSR_XMIT_ACTIVE_MASK) != 0) {
+
+ tx_status &= ~XEL_TSR_XMIT_ACTIVE_MASK;
+ __raw_writel(tx_status, base_addr + XEL_BUFFER_OFFSET +
+ XEL_TSR_OFFSET);
+
+ tx_complete = true;
+ }
+
+ /* If there was a Tx interrupt, call the Tx Handler */
+ if (tx_complete != 0)
+ xemaclite_tx_handler(dev);
+
+ return IRQ_HANDLED;
+}
+
+/**********************/
+/* MDIO Bus functions */
+/**********************/
+
+/**
+ * xemaclite_mdio_wait - Wait for the MDIO to be ready to use
+ * @lp: Pointer to the Emaclite device private data
+ *
+ * This function waits till the device is ready to accept a new MDIO
+ * request.
+ *
+ * Return: 0 for success or ETIMEDOUT for a timeout
+ */
+
+static int xemaclite_mdio_wait(struct net_local *lp)
+{
+ unsigned long end = jiffies + 2;
+
+ /* wait for the MDIO interface to not be busy or timeout
+ after some time.
+ */
+ while (__raw_readl(lp->base_addr + XEL_MDIOCTRL_OFFSET) &
+ XEL_MDIOCTRL_MDIOSTS_MASK) {
+ if (time_before_eq(end, jiffies)) {
+ WARN_ON(1);
+ return -ETIMEDOUT;
+ }
+ msleep(1);
+ }
+ return 0;
+}
+
+/**
+ * xemaclite_mdio_read - Read from a given MII management register
+ * @bus: the mii_bus struct
+ * @phy_id: the phy address
+ * @reg: register number to read from
+ *
+ * This function waits till the device is ready to accept a new MDIO
+ * request and then writes the phy address to the MDIO Address register
+ * and reads data from MDIO Read Data register, when its available.
+ *
+ * Return: Value read from the MII management register
+ */
+static int xemaclite_mdio_read(struct mii_bus *bus, int phy_id, int reg)
+{
+ struct net_local *lp = bus->priv;
+ u32 ctrl_reg;
+ u32 rc;
+
+ if (xemaclite_mdio_wait(lp))
+ return -ETIMEDOUT;
+
+ /* Write the PHY address, register number and set the OP bit in the
+ * MDIO Address register. Set the Status bit in the MDIO Control
+ * register to start a MDIO read transaction.
+ */
+ ctrl_reg = __raw_readl(lp->base_addr + XEL_MDIOCTRL_OFFSET);
+ __raw_writel(XEL_MDIOADDR_OP_MASK |
+ ((phy_id << XEL_MDIOADDR_PHYADR_SHIFT) | reg),
+ lp->base_addr + XEL_MDIOADDR_OFFSET);
+ __raw_writel(ctrl_reg | XEL_MDIOCTRL_MDIOSTS_MASK,
+ lp->base_addr + XEL_MDIOCTRL_OFFSET);
+
+ if (xemaclite_mdio_wait(lp))
+ return -ETIMEDOUT;
+
+ rc = __raw_readl(lp->base_addr + XEL_MDIORD_OFFSET);
+
+ dev_dbg(&lp->ndev->dev,
+ "xemaclite_mdio_read(phy_id=%i, reg=%x) == %x\n",
+ phy_id, reg, rc);
+
+ return rc;
+}
+
+/**
+ * xemaclite_mdio_write - Write to a given MII management register
+ * @bus: the mii_bus struct
+ * @phy_id: the phy address
+ * @reg: register number to write to
+ * @val: value to write to the register number specified by reg
+ *
+ * This function waits till the device is ready to accept a new MDIO
+ * request and then writes the val to the MDIO Write Data register.
+ */
+static int xemaclite_mdio_write(struct mii_bus *bus, int phy_id, int reg,
+ u16 val)
+{
+ struct net_local *lp = bus->priv;
+ u32 ctrl_reg;
+
+ dev_dbg(&lp->ndev->dev,
+ "xemaclite_mdio_write(phy_id=%i, reg=%x, val=%x)\n",
+ phy_id, reg, val);
+
+ if (xemaclite_mdio_wait(lp))
+ return -ETIMEDOUT;
+
+ /* Write the PHY address, register number and clear the OP bit in the
+ * MDIO Address register and then write the value into the MDIO Write
+ * Data register. Finally, set the Status bit in the MDIO Control
+ * register to start a MDIO write transaction.
+ */
+ ctrl_reg = __raw_readl(lp->base_addr + XEL_MDIOCTRL_OFFSET);
+ __raw_writel(~XEL_MDIOADDR_OP_MASK &
+ ((phy_id << XEL_MDIOADDR_PHYADR_SHIFT) | reg),
+ lp->base_addr + XEL_MDIOADDR_OFFSET);
+ __raw_writel(val, lp->base_addr + XEL_MDIOWR_OFFSET);
+ __raw_writel(ctrl_reg | XEL_MDIOCTRL_MDIOSTS_MASK,
+ lp->base_addr + XEL_MDIOCTRL_OFFSET);
+
+ return 0;
+}
+
+/**
+ * xemaclite_mdio_setup - Register mii_bus for the Emaclite device
+ * @lp: Pointer to the Emaclite device private data
+ * @ofdev: Pointer to OF device structure
+ *
+ * This function enables MDIO bus in the Emaclite device and registers a
+ * mii_bus.
+ *
+ * Return: 0 upon success or a negative error upon failure
+ */
+static int xemaclite_mdio_setup(struct net_local *lp, struct device *dev)
+{
+ struct mii_bus *bus;
+ int rc;
+ struct resource res;
+ struct device_node *np = of_get_parent(lp->phy_node);
+ struct device_node *npp;
+
+ /* Don't register the MDIO bus if the phy_node or its parent node
+ * can't be found.
+ */
+ if (!np) {
+ dev_err(dev, "Failed to register mdio bus.\n");
+ return -ENODEV;
+ }
+ npp = of_get_parent(np);
+
+ of_address_to_resource(npp, 0, &res);
+ if (lp->ndev->mem_start != res.start) {
+ struct phy_device *phydev;
+ phydev = of_phy_find_device(lp->phy_node);
+ if (!phydev)
+ dev_info(dev,
+ "MDIO of the phy is not registered yet\n");
+ return 0;
+ }
+
+ /* Enable the MDIO bus by asserting the enable bit in MDIO Control
+ * register.
+ */
+ __raw_writel(XEL_MDIOCTRL_MDIOEN_MASK,
+ lp->base_addr + XEL_MDIOCTRL_OFFSET);
+
+ bus = mdiobus_alloc();
+ if (!bus) {
+ dev_err(dev, "Failed to allocate mdiobus\n");
+ return -ENOMEM;
+ }
+
+ snprintf(bus->id, MII_BUS_ID_SIZE, "%.8llx",
+ (unsigned long long)res.start);
+ bus->priv = lp;
+ bus->name = "Xilinx Emaclite MDIO";
+ bus->read = xemaclite_mdio_read;
+ bus->write = xemaclite_mdio_write;
+ bus->parent = dev;
+ bus->irq = lp->mdio_irqs; /* preallocated IRQ table */
+
+ lp->mii_bus = bus;
+
+ rc = of_mdiobus_register(bus, np);
+ if (rc) {
+ dev_err(dev, "Failed to register mdio bus.\n");
+ goto err_register;
+ }
+
+ return 0;
+
+err_register:
+ mdiobus_free(bus);
+ return rc;
+}
+
+/**
+ * xemaclite_adjust_link - Link state callback for the Emaclite device
+ * @ndev: pointer to net_device struct
+ *
+ * There's nothing in the Emaclite device to be configured when the link
+ * state changes. We just print the status.
+ */
+static void xemaclite_adjust_link(struct net_device *ndev)
+{
+ struct net_local *lp = netdev_priv(ndev);
+ struct phy_device *phy = lp->phy_dev;
+ int link_state;
+
+ /* hash together the state values to decide if something has changed */
+ link_state = phy->speed | (phy->duplex << 1) | phy->link;
+
+ if (lp->last_link != link_state) {
+ lp->last_link = link_state;
+ phy_print_status(phy);
+ }
+}
+
+/**
+ * xemaclite_open - Open the network device
+ * @dev: Pointer to the network device
+ *
+ * This function sets the MAC address, requests an IRQ and enables interrupts
+ * for the Emaclite device and starts the Tx queue.
+ * It also connects to the phy device, if MDIO is included in Emaclite device.
+ */
+static int xemaclite_open(struct net_device *dev)
+{
+ struct net_local *lp = netdev_priv(dev);
+ int retval;
+
+ /* Just to be safe, stop the device first */
+ xemaclite_disable_interrupts(lp);
+
+ if (lp->phy_node) {
+ u32 bmcr;
+
+ lp->phy_dev = of_phy_connect(lp->ndev, lp->phy_node,
+ xemaclite_adjust_link, 0,
+ PHY_INTERFACE_MODE_MII);
+ if (!lp->phy_dev) {
+ dev_err(&lp->ndev->dev, "of_phy_connect() failed\n");
+ return -ENODEV;
+ }
+
+ /* EmacLite doesn't support giga-bit speeds */
+ lp->phy_dev->supported &= (PHY_BASIC_FEATURES);
+ lp->phy_dev->advertising = lp->phy_dev->supported;
+
+ /* Don't advertise 1000BASE-T Full/Half duplex speeds */
+ phy_write(lp->phy_dev, MII_CTRL1000, 0);
+
+ /* Advertise only 10 and 100mbps full/half duplex speeds */
+ phy_write(lp->phy_dev, MII_ADVERTISE, ADVERTISE_ALL |
+ ADVERTISE_CSMA);
+
+ /* Restart auto negotiation */
+ bmcr = phy_read(lp->phy_dev, MII_BMCR);
+ bmcr |= (BMCR_ANENABLE | BMCR_ANRESTART);
+ phy_write(lp->phy_dev, MII_BMCR, bmcr);
+
+ phy_start(lp->phy_dev);
+ }
+
+ /* Set the MAC address each time opened */
+ xemaclite_update_address(lp, dev->dev_addr);
+
+ /* Grab the IRQ */
+ retval = request_irq(dev->irq, xemaclite_interrupt, 0, dev->name, dev);
+ if (retval) {
+ dev_err(&lp->ndev->dev, "Could not allocate interrupt %d\n",
+ dev->irq);
+ if (lp->phy_dev)
+ phy_disconnect(lp->phy_dev);
+ lp->phy_dev = NULL;
+
+ return retval;
+ }
+
+ /* Enable Interrupts */
+ xemaclite_enable_interrupts(lp);
+
+ /* We're ready to go */
+ netif_start_queue(dev);
+
+ return 0;
+}
+
+/**
+ * xemaclite_close - Close the network device
+ * @dev: Pointer to the network device
+ *
+ * This function stops the Tx queue, disables interrupts and frees the IRQ for
+ * the Emaclite device.
+ * It also disconnects the phy device associated with the Emaclite device.
+ */
+static int xemaclite_close(struct net_device *dev)
+{
+ struct net_local *lp = netdev_priv(dev);
+
+ netif_stop_queue(dev);
+ xemaclite_disable_interrupts(lp);
+ free_irq(dev->irq, dev);
+
+ if (lp->phy_dev)
+ phy_disconnect(lp->phy_dev);
+ lp->phy_dev = NULL;
+
+ return 0;
+}
+
+/**
+ * xemaclite_send - Transmit a frame
+ * @orig_skb: Pointer to the socket buffer to be transmitted
+ * @dev: Pointer to the network device
+ *
+ * This function checks if the Tx buffer of the Emaclite device is free to send
+ * data. If so, it fills the Tx buffer with data from socket buffer data,
+ * updates the stats and frees the socket buffer. The Tx completion is signaled
+ * by an interrupt. If the Tx buffer isn't free, then the socket buffer is
+ * deferred and the Tx queue is stopped so that the deferred socket buffer can
+ * be transmitted when the Emaclite device is free to transmit data.
+ *
+ * Return: 0, always.
+ */
+static int xemaclite_send(struct sk_buff *orig_skb, struct net_device *dev)
+{
+ struct net_local *lp = netdev_priv(dev);
+ struct sk_buff *new_skb;
+ unsigned int len;
+ unsigned long flags;
+
+ len = orig_skb->len;
+
+ new_skb = orig_skb;
+
+ spin_lock_irqsave(&lp->reset_lock, flags);
+ if (xemaclite_send_data(lp, (u8 *) new_skb->data, len) != 0) {
+ /* If the Emaclite Tx buffer is busy, stop the Tx queue and
+ * defer the skb for transmission during the ISR, after the
+ * current transmission is complete */
+ netif_stop_queue(dev);
+ lp->deferred_skb = new_skb;
+ /* Take the time stamp now, since we can't do this in an ISR. */
+ skb_tx_timestamp(new_skb);
+ spin_unlock_irqrestore(&lp->reset_lock, flags);
+ return 0;
+ }
+ spin_unlock_irqrestore(&lp->reset_lock, flags);
+
+ skb_tx_timestamp(new_skb);
+
+ dev->stats.tx_bytes += len;
+ dev_consume_skb_any(new_skb);
+
+ return 0;
+}
+
+/**
+ * xemaclite_remove_ndev - Free the network device
+ * @ndev: Pointer to the network device to be freed
+ *
+ * This function un maps the IO region of the Emaclite device and frees the net
+ * device.
+ */
+static void xemaclite_remove_ndev(struct net_device *ndev)
+{
+ if (ndev) {
+ free_netdev(ndev);
+ }
+}
+
+/**
+ * get_bool - Get a parameter from the OF device
+ * @ofdev: Pointer to OF device structure
+ * @s: Property to be retrieved
+ *
+ * This function looks for a property in the device node and returns the value
+ * of the property if its found or 0 if the property is not found.
+ *
+ * Return: Value of the parameter if the parameter is found, or 0 otherwise
+ */
+static bool get_bool(struct platform_device *ofdev, const char *s)
+{
+ u32 *p = (u32 *)of_get_property(ofdev->dev.of_node, s, NULL);
+
+ if (p) {
+ return (bool)*p;
+ } else {
+ dev_warn(&ofdev->dev, "Parameter %s not found,"
+ "defaulting to false\n", s);
+ return false;
+ }
+}
+
+static struct net_device_ops xemaclite_netdev_ops;
+
+/**
+ * xemaclite_of_probe - Probe method for the Emaclite device.
+ * @ofdev: Pointer to OF device structure
+ * @match: Pointer to the structure used for matching a device
+ *
+ * This function probes for the Emaclite device in the device tree.
+ * It initializes the driver data structure and the hardware, sets the MAC
+ * address and registers the network device.
+ * It also registers a mii_bus for the Emaclite device, if MDIO is included
+ * in the device.
+ *
+ * Return: 0, if the driver is bound to the Emaclite device, or
+ * a negative error if there is failure.
+ */
+static int xemaclite_of_probe(struct platform_device *ofdev)
+{
+ struct resource *res;
+ struct net_device *ndev = NULL;
+ struct net_local *lp = NULL;
+ struct device *dev = &ofdev->dev;
+ const void *mac_address;
+
+ int rc = 0;
+
+ dev_info(dev, "Device Tree Probing\n");
+
+ /* Create an ethernet device instance */
+ ndev = alloc_etherdev(sizeof(struct net_local));
+ if (!ndev)
+ return -ENOMEM;
+
+ dev_set_drvdata(dev, ndev);
+ SET_NETDEV_DEV(ndev, &ofdev->dev);
+
+ lp = netdev_priv(ndev);
+ lp->ndev = ndev;
+
+ /* Get IRQ for the device */
+ res = platform_get_resource(ofdev, IORESOURCE_IRQ, 0);
+ if (!res) {
+ dev_err(dev, "no IRQ found\n");
+ rc = -ENXIO;
+ goto error;
+ }
+
+ ndev->irq = res->start;
+
+ res = platform_get_resource(ofdev, IORESOURCE_MEM, 0);
+ lp->base_addr = devm_ioremap_resource(&ofdev->dev, res);
+ if (IS_ERR(lp->base_addr)) {
+ rc = PTR_ERR(lp->base_addr);
+ goto error;
+ }
+
+ ndev->mem_start = res->start;
+ ndev->mem_end = res->end;
+
+ spin_lock_init(&lp->reset_lock);
+ lp->next_tx_buf_to_use = 0x0;
+ lp->next_rx_buf_to_use = 0x0;
+ lp->tx_ping_pong = get_bool(ofdev, "xlnx,tx-ping-pong");
+ lp->rx_ping_pong = get_bool(ofdev, "xlnx,rx-ping-pong");
+ mac_address = of_get_mac_address(ofdev->dev.of_node);
+
+ if (mac_address)
+ /* Set the MAC address. */
+ memcpy(ndev->dev_addr, mac_address, ETH_ALEN);
+ else
+ dev_warn(dev, "No MAC address found\n");
+
+ /* Clear the Tx CSR's in case this is a restart */
+ __raw_writel(0, lp->base_addr + XEL_TSR_OFFSET);
+ __raw_writel(0, lp->base_addr + XEL_BUFFER_OFFSET + XEL_TSR_OFFSET);
+
+ /* Set the MAC address in the EmacLite device */
+ xemaclite_update_address(lp, ndev->dev_addr);
+
+ lp->phy_node = of_parse_phandle(ofdev->dev.of_node, "phy-handle", 0);
+ rc = xemaclite_mdio_setup(lp, &ofdev->dev);
+ if (rc)
+ dev_warn(&ofdev->dev, "error registering MDIO bus\n");
+
+ dev_info(dev, "MAC address is now %pM\n", ndev->dev_addr);
+
+ ndev->netdev_ops = &xemaclite_netdev_ops;
+ ndev->flags &= ~IFF_MULTICAST;
+ ndev->watchdog_timeo = TX_TIMEOUT;
+
+ /* Finally, register the device */
+ rc = register_netdev(ndev);
+ if (rc) {
+ dev_err(dev,
+ "Cannot register network device, aborting\n");
+ goto error;
+ }
+
+ dev_info(dev,
+ "Xilinx EmacLite at 0x%08X mapped to 0x%08X, irq=%d\n",
+ (unsigned int __force)ndev->mem_start,
+ (unsigned int __force)lp->base_addr, ndev->irq);
+ return 0;
+
+error:
+ xemaclite_remove_ndev(ndev);
+ return rc;
+}
+
+/**
+ * xemaclite_of_remove - Unbind the driver from the Emaclite device.
+ * @of_dev: Pointer to OF device structure
+ *
+ * This function is called if a device is physically removed from the system or
+ * if the driver module is being unloaded. It frees any resources allocated to
+ * the device.
+ *
+ * Return: 0, always.
+ */
+static int xemaclite_of_remove(struct platform_device *of_dev)
+{
+ struct net_device *ndev = platform_get_drvdata(of_dev);
+
+ struct net_local *lp = netdev_priv(ndev);
+
+ /* Un-register the mii_bus, if configured */
+ if (lp->has_mdio) {
+ mdiobus_unregister(lp->mii_bus);
+ kfree(lp->mii_bus->irq);
+ mdiobus_free(lp->mii_bus);
+ lp->mii_bus = NULL;
+ }
+
+ unregister_netdev(ndev);
+
+ of_node_put(lp->phy_node);
+ lp->phy_node = NULL;
+
+ xemaclite_remove_ndev(ndev);
+
+ return 0;
+}
+
+#ifdef CONFIG_NET_POLL_CONTROLLER
+static void
+xemaclite_poll_controller(struct net_device *ndev)
+{
+ disable_irq(ndev->irq);
+ xemaclite_interrupt(ndev->irq, ndev);
+ enable_irq(ndev->irq);
+}
+#endif
+
+static struct net_device_ops xemaclite_netdev_ops = {
+ .ndo_open = xemaclite_open,
+ .ndo_stop = xemaclite_close,
+ .ndo_start_xmit = xemaclite_send,
+ .ndo_set_mac_address = xemaclite_set_mac_address,
+ .ndo_tx_timeout = xemaclite_tx_timeout,
+#ifdef CONFIG_NET_POLL_CONTROLLER
+ .ndo_poll_controller = xemaclite_poll_controller,
+#endif
+};
+
+/* Match table for OF platform binding */
+static const struct of_device_id xemaclite_of_match[] = {
+ { .compatible = "xlnx,opb-ethernetlite-1.01.a", },
+ { .compatible = "xlnx,opb-ethernetlite-1.01.b", },
+ { .compatible = "xlnx,xps-ethernetlite-1.00.a", },
+ { .compatible = "xlnx,xps-ethernetlite-2.00.a", },
+ { .compatible = "xlnx,xps-ethernetlite-2.01.a", },
+ { .compatible = "xlnx,xps-ethernetlite-3.00.a", },
+ { /* end of list */ },
+};
+MODULE_DEVICE_TABLE(of, xemaclite_of_match);
+
+static struct platform_driver xemaclite_of_driver = {
+ .driver = {
+ .name = DRIVER_NAME,
+ .of_match_table = xemaclite_of_match,
+ },
+ .probe = xemaclite_of_probe,
+ .remove = xemaclite_of_remove,
+};
+
+module_platform_driver(xemaclite_of_driver);
+
+MODULE_AUTHOR("Xilinx, Inc.");
+MODULE_DESCRIPTION("Xilinx Ethernet MAC Lite driver");
+MODULE_LICENSE("GPL");
Code Review / kvmfornfv.git / blobdiff