diff options
Diffstat (limited to 'drivers/net/xilinx_emaclite.c')
| -rw-r--r-- | drivers/net/xilinx_emaclite.c | 1040 |
1 files changed, 1040 insertions, 0 deletions
diff --git a/drivers/net/xilinx_emaclite.c b/drivers/net/xilinx_emaclite.c new file mode 100644 index 00000000000..dc22782633a --- /dev/null +++ b/drivers/net/xilinx_emaclite.c @@ -0,0 +1,1040 @@ +/* + * 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@petalogix.com>. + * + * 2007-2009 (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/init.h> +#include <linux/netdevice.h> +#include <linux/etherdevice.h> +#include <linux/skbuff.h> +#include <linux/io.h> + +#include <linux/of_device.h> +#include <linux/of_platform.h> + +#define DRIVER_NAME "xilinx_emaclite" + +/* Register offsets for the EmacLite Core */ +#define XEL_TXBUFF_OFFSET 0x0 /* Transmit Buffer */ +#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 */ + +/* 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 + */ +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; +}; + + +/*************************/ +/* 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 = in_be32(drvdata->base_addr + XEL_TSR_OFFSET); + out_be32(drvdata->base_addr + XEL_TSR_OFFSET, + reg_data | XEL_TSR_XMIT_IE_MASK); + + /* Enable the Tx interrupts for the second Buffer if + * configured in HW */ + if (drvdata->tx_ping_pong != 0) { + reg_data = in_be32(drvdata->base_addr + + XEL_BUFFER_OFFSET + XEL_TSR_OFFSET); + out_be32(drvdata->base_addr + XEL_BUFFER_OFFSET + + XEL_TSR_OFFSET, + reg_data | XEL_TSR_XMIT_IE_MASK); + } + + /* Enable the Rx interrupts for the first buffer */ + reg_data = in_be32(drvdata->base_addr + XEL_RSR_OFFSET); + out_be32(drvdata->base_addr + XEL_RSR_OFFSET, + reg_data | XEL_RSR_RECV_IE_MASK); + + /* Enable the Rx interrupts for the second Buffer if + * configured in HW */ + if (drvdata->rx_ping_pong != 0) { + reg_data = in_be32(drvdata->base_addr + XEL_BUFFER_OFFSET + + XEL_RSR_OFFSET); + out_be32(drvdata->base_addr + XEL_BUFFER_OFFSET + + XEL_RSR_OFFSET, + reg_data | XEL_RSR_RECV_IE_MASK); + } + + /* Enable the Global Interrupt Enable */ + out_be32(drvdata->base_addr + XEL_GIER_OFFSET, XEL_GIER_GIE_MASK); +} + +/** + * 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 */ + out_be32(drvdata->base_addr + XEL_GIER_OFFSET, XEL_GIER_GIE_MASK); + + /* Disable the Tx interrupts for the first buffer */ + reg_data = in_be32(drvdata->base_addr + XEL_TSR_OFFSET); + out_be32(drvdata->base_addr + XEL_TSR_OFFSET, + reg_data & (~XEL_TSR_XMIT_IE_MASK)); + + /* Disable the Tx interrupts for the second Buffer + * if configured in HW */ + if (drvdata->tx_ping_pong != 0) { + reg_data = in_be32(drvdata->base_addr + XEL_BUFFER_OFFSET + + XEL_TSR_OFFSET); + out_be32(drvdata->base_addr + XEL_BUFFER_OFFSET + + XEL_TSR_OFFSET, + reg_data & (~XEL_TSR_XMIT_IE_MASK)); + } + + /* Disable the Rx interrupts for the first buffer */ + reg_data = in_be32(drvdata->base_addr + XEL_RSR_OFFSET); + out_be32(drvdata->base_addr + XEL_RSR_OFFSET, + reg_data & (~XEL_RSR_RECV_IE_MASK)); + + /* Disable the Rx interrupts for the second buffer + * if configured in HW */ + if (drvdata->rx_ping_pong != 0) { + + reg_data = in_be32(drvdata->base_addr + XEL_BUFFER_OFFSET + + XEL_RSR_OFFSET); + out_be32(drvdata->base_addr + XEL_BUFFER_OFFSET + + XEL_RSR_OFFSET, + reg_data & (~XEL_RSR_RECV_IE_MASK)); + } +} + +/** + * 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 = (u16 *) src_ptr; + align_buffer = 0; + + for (; length > 3; length -= 4) { + to_u16_ptr = (u16 *) ((void *) &align_buffer); + *to_u16_ptr++ = *from_u16_ptr++; + *to_u16_ptr++ = *from_u16_ptr++; + + /* 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++; + + *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 = in_be32(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 = in_be32(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); + + out_be32(addr + XEL_TPLR_OFFSET, (byte_count & XEL_TPLR_LENGTH_MASK)); + + /* 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 = in_be32(addr + XEL_TSR_OFFSET); + reg_data |= (XEL_TSR_XMIT_BUSY_MASK | XEL_TSR_XMIT_ACTIVE_MASK); + out_be32(addr + XEL_TSR_OFFSET, reg_data); + + 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 = in_be32(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 = in_be32(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 = ((in_be32(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 = ((in_be32(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 = in_be32(addr + XEL_RSR_OFFSET); + reg_data &= ~XEL_RSR_RECV_DONE_MASK; + out_be32(addr + XEL_RSR_OFFSET, reg_data); + + return length; +} + +/** + * xemaclite_set_mac_address - Set the MAC address for this 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_set_mac_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); + + out_be32(addr + XEL_TPLR_OFFSET, ETH_ALEN); + + /* Update the MAC address in the EmacLite */ + reg_data = in_be32(addr + XEL_TSR_OFFSET); + out_be32(addr + XEL_TSR_OFFSET, reg_data | XEL_TSR_PROG_MAC_ADDR); + + /* Wait for EmacLite to finish with the MAC address update */ + while ((in_be32(addr + XEL_TSR_OFFSET) & + XEL_TSR_PROG_MAC_ADDR) != 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 = (struct net_local *) 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 = 0xffffffff - TX_TIMEOUT - 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 = (struct net_local *) 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; + 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 = (struct net_local *) netdev_priv(dev); + struct sk_buff *skb; + unsigned int align; + u32 len; + + len = ETH_FRAME_LEN + ETH_FCS_LEN; + skb = dev_alloc_skb(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->dev = dev; /* Fill out required meta-data */ + + skb->protocol = eth_type_trans(skb, dev); + skb->ip_summed = CHECKSUM_NONE; + + dev->stats.rx_packets++; + dev->stats.rx_bytes += len; + + 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 = 0; + struct net_device *dev = dev_id; + struct net_local *lp = (struct net_local *) netdev_priv(dev); + void __iomem *base_addr = lp->base_addr; + u32 tx_status; + + /* Check if there is Rx Data available */ + if ((in_be32(base_addr + XEL_RSR_OFFSET) & XEL_RSR_RECV_DONE_MASK) || + (in_be32(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 = in_be32(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; + out_be32(base_addr + XEL_TSR_OFFSET, tx_status); + + tx_complete = 1; + } + + /* Check if the Transmission for the second buffer is completed */ + tx_status = in_be32(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; + out_be32(base_addr + XEL_BUFFER_OFFSET + XEL_TSR_OFFSET, + tx_status); + + tx_complete = 1; + } + + /* If there was a Tx interrupt, call the Tx Handler */ + if (tx_complete != 0) + xemaclite_tx_handler(dev); + + return IRQ_HANDLED; +} + +/** + * 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. + */ +static int xemaclite_open(struct net_device *dev) +{ + struct net_local *lp = (struct net_local *) netdev_priv(dev); + int retval; + + /* Just to be safe, stop the device first */ + xemaclite_disable_interrupts(lp); + + /* Set the MAC address each time opened */ + xemaclite_set_mac_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); + 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. + */ +static int xemaclite_close(struct net_device *dev) +{ + struct net_local *lp = (struct net_local *) netdev_priv(dev); + + netif_stop_queue(dev); + xemaclite_disable_interrupts(lp); + free_irq(dev->irq, dev); + + return 0; +} + +/** + * xemaclite_get_stats - Get the stats for the net_device + * @dev: Pointer to the network device + * + * This function returns the address of the 'net_device_stats' structure for the + * given network device. This structure holds usage statistics for the network + * device. + * + * Return: Pointer to the net_device_stats structure. + */ +static struct net_device_stats *xemaclite_get_stats(struct net_device *dev) +{ + return &dev->stats; +} + +/** + * 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 = (struct net_local *) 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 at a later point when the + * current transmission is complete */ + netif_stop_queue(dev); + lp->deferred_skb = new_skb; + spin_unlock_irqrestore(&lp->reset_lock, flags); + return 0; + } + spin_unlock_irqrestore(&lp->reset_lock, flags); + + dev->stats.tx_bytes += len; + dev_kfree_skb(new_skb); + dev->trans_start = jiffies; + + return 0; +} + +/** + * xemaclite_ioctl - Perform IO Control operations on the network device + * @dev: Pointer to the network device + * @rq: Pointer to the interface request structure + * @cmd: IOCTL command + * + * The only IOCTL operation supported by this function is setting the MAC + * address. An error is reported if any other operations are requested. + * + * Return: 0 to indicate success, or a negative error for failure. + */ +static int xemaclite_ioctl(struct net_device *dev, struct ifreq *rq, int cmd) +{ + struct net_local *lp = (struct net_local *) netdev_priv(dev); + struct hw_addr_data *hw_addr = (struct hw_addr_data *) &rq->ifr_hwaddr; + + switch (cmd) { + case SIOCETHTOOL: + return -EIO; + + case SIOCSIFHWADDR: + dev_err(&lp->ndev->dev, "SIOCSIFHWADDR\n"); + + /* Copy MAC address in from user space */ + copy_from_user((void __force *) dev->dev_addr, + (void __user __force *) hw_addr, + IFHWADDRLEN); + xemaclite_set_mac_address(lp, dev->dev_addr); + break; + default: + return -EOPNOTSUPP; + } + + 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) { + struct net_local *lp = (struct net_local *) netdev_priv(ndev); + + if (lp->base_addr) + iounmap((void __iomem __force *) (lp->base_addr)); + 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 of_device *ofdev, const char *s) +{ + u32 *p = (u32 *)of_get_property(ofdev->node, s, NULL); + + if (p) { + return (bool)*p; + } else { + dev_warn(&ofdev->dev, "Parameter %s not found," + "defaulting to false\n", s); + return 0; + } +} + +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. + * + * Return: 0, if the driver is bound to the Emaclite device, or + * a negative error if there is failure. + */ +static int __devinit xemaclite_of_probe(struct of_device *ofdev, + const struct of_device_id *match) +{ + struct resource r_irq; /* Interrupt resources */ + struct resource r_mem; /* IO mem resources */ + 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"); + + /* Get iospace for the device */ + rc = of_address_to_resource(ofdev->node, 0, &r_mem); + if (rc) { + dev_err(dev, "invalid address\n"); + return rc; + } + + /* Get IRQ for the device */ + rc = of_irq_to_resource(ofdev->node, 0, &r_irq); + if (rc == NO_IRQ) { + dev_err(dev, "no IRQ found\n"); + return rc; + } + + /* Create an ethernet device instance */ + ndev = alloc_etherdev(sizeof(struct net_local)); + if (!ndev) { + dev_err(dev, "Could not allocate network device\n"); + return -ENOMEM; + } + + dev_set_drvdata(dev, ndev); + + ndev->irq = r_irq.start; + ndev->mem_start = r_mem.start; + ndev->mem_end = r_mem.end; + + lp = netdev_priv(ndev); + lp->ndev = ndev; + + if (!request_mem_region(ndev->mem_start, + ndev->mem_end - ndev->mem_start + 1, + DRIVER_NAME)) { + dev_err(dev, "Couldn't lock memory region at %p\n", + (void *)ndev->mem_start); + rc = -EBUSY; + goto error2; + } + + /* Get the virtual base address for the device */ + lp->base_addr = ioremap(r_mem.start, r_mem.end - r_mem.start + 1); + if (NULL == lp->base_addr) { + dev_err(dev, "EmacLite: Could not allocate iomem\n"); + rc = -EIO; + goto error1; + } + + 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->node); + + if (mac_address) + /* Set the MAC address. */ + memcpy(ndev->dev_addr, mac_address, 6); + else + dev_warn(dev, "No MAC address found\n"); + + /* Clear the Tx CSR's in case this is a restart */ + out_be32(lp->base_addr + XEL_TSR_OFFSET, 0); + out_be32(lp->base_addr + XEL_BUFFER_OFFSET + XEL_TSR_OFFSET, 0); + + /* Set the MAC address in the EmacLite device */ + xemaclite_set_mac_address(lp, ndev->dev_addr); + + dev_info(dev, + "MAC address is now %2x:%2x:%2x:%2x:%2x:%2x\n", + ndev->dev_addr[0], ndev->dev_addr[1], + ndev->dev_addr[2], ndev->dev_addr[3], + ndev->dev_addr[4], ndev->dev_addr[5]); + + 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 error1; + } + + 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; + +error1: + release_mem_region(ndev->mem_start, r_mem.end - r_mem.start + 1); + +error2: + 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 __devexit xemaclite_of_remove(struct of_device *of_dev) +{ + struct device *dev = &of_dev->dev; + struct net_device *ndev = dev_get_drvdata(dev); + + unregister_netdev(ndev); + + release_mem_region(ndev->mem_start, ndev->mem_end-ndev->mem_start + 1); + + xemaclite_remove_ndev(ndev); + + dev_set_drvdata(dev, NULL); + + return 0; +} + +static struct net_device_ops xemaclite_netdev_ops = { + .ndo_open = xemaclite_open, + .ndo_stop = xemaclite_close, + .ndo_start_xmit = xemaclite_send, + .ndo_do_ioctl = xemaclite_ioctl, + .ndo_tx_timeout = xemaclite_tx_timeout, + .ndo_get_stats = xemaclite_get_stats, +}; + +/* Match table for OF platform binding */ +static struct of_device_id xemaclite_of_match[] __devinitdata = { + { .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", }, + { /* end of list */ }, +}; +MODULE_DEVICE_TABLE(of, xemaclite_of_match); + +static struct of_platform_driver xemaclite_of_driver = { + .name = DRIVER_NAME, + .match_table = xemaclite_of_match, + .probe = xemaclite_of_probe, + .remove = __devexit_p(xemaclite_of_remove), +}; + +/** + * xgpiopss_init - Initial driver registration call + * + * Return: 0 upon success, or a negative error upon failure. + */ +static int __init xemaclite_init(void) +{ + /* No kernel boot options used, we just need to register the driver */ + return of_register_platform_driver(&xemaclite_of_driver); +} + +/** + * xemaclite_cleanup - Driver un-registration call + */ +static void __exit xemaclite_cleanup(void) +{ + of_unregister_platform_driver(&xemaclite_of_driver); +} + +module_init(xemaclite_init); +module_exit(xemaclite_cleanup); + +MODULE_AUTHOR("Xilinx, Inc."); +MODULE_DESCRIPTION("Xilinx Ethernet MAC Lite driver"); +MODULE_LICENSE("GPL"); |