/* * 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 . * * 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 #include #include #include #include #include #include #include #include #include #include #include #include #include #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) #ifdef __BIG_ENDIAN #define xemaclite_readl ioread32be #define xemaclite_writel iowrite32be #else #define xemaclite_readl ioread32 #define xemaclite_writel iowrite32 #endif /** * 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 * @last_link: last link status */ 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 last_link; }; /*************************/ /* 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 = xemaclite_readl(drvdata->base_addr + XEL_TSR_OFFSET); xemaclite_writel(reg_data | XEL_TSR_XMIT_IE_MASK, drvdata->base_addr + XEL_TSR_OFFSET); /* Enable the Rx interrupts for the first buffer */ xemaclite_writel(XEL_RSR_RECV_IE_MASK, drvdata->base_addr + XEL_RSR_OFFSET); /* Enable the Global Interrupt Enable */ xemaclite_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 */ xemaclite_writel(XEL_GIER_GIE_MASK, drvdata->base_addr + XEL_GIER_OFFSET); /* Disable the Tx interrupts for the first buffer */ reg_data = xemaclite_readl(drvdata->base_addr + XEL_TSR_OFFSET); xemaclite_writel(reg_data & (~XEL_TSR_XMIT_IE_MASK), drvdata->base_addr + XEL_TSR_OFFSET); /* Disable the Rx interrupts for the first buffer */ reg_data = xemaclite_readl(drvdata->base_addr + XEL_RSR_OFFSET); xemaclite_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 = xemaclite_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 = xemaclite_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); xemaclite_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 = xemaclite_readl(addr + XEL_TSR_OFFSET); reg_data |= (XEL_TSR_XMIT_BUSY_MASK | XEL_TSR_XMIT_ACTIVE_MASK); xemaclite_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 * @maxlen: Maximum supported ethernet packet length * * 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, int maxlen) { 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 = xemaclite_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 = xemaclite_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(xemaclite_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_DATA_LEN) { if (proto_type == ETH_P_IP) { length = ((ntohl(xemaclite_readl(addr + XEL_HEADER_IP_LENGTH_OFFSET + XEL_RXBUFF_OFFSET)) >> XEL_HEADER_SHIFT) & XEL_RPLR_LENGTH_MASK); length = min_t(u16, length, ETH_DATA_LEN); 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; if (WARN_ON(length > maxlen)) length = maxlen; /* Read from the EmacLite device */ xemaclite_aligned_read((u32 __force *)(addr + XEL_RXBUFF_OFFSET), data, length); /* Acknowledge the frame */ reg_data = xemaclite_readl(addr + XEL_RSR_OFFSET); reg_data &= ~XEL_RSR_RECV_DONE_MASK; xemaclite_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); xemaclite_writel(ETH_ALEN, addr + XEL_TPLR_OFFSET); /* Update the MAC address in the EmacLite */ reg_data = xemaclite_readl(addr + XEL_TSR_OFFSET); xemaclite_writel(reg_data | XEL_TSR_PROG_MAC_ADDR, addr + XEL_TSR_OFFSET); /* Wait for EmacLite to finish with the MAC address update */ while ((xemaclite_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 * @address: 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 */ netif_trans_update(dev); /* 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) return; if (xemaclite_send_data(lp, (u8 *)lp->deferred_skb->data, lp->deferred_skb->len)) return; dev->stats.tx_bytes += lp->deferred_skb->len; dev_kfree_skb_irq(lp->deferred_skb); lp->deferred_skb = NULL; netif_trans_update(dev); /* 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, len); 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 * * Return: IRQ_HANDLED * * 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 ((xemaclite_readl(base_addr + XEL_RSR_OFFSET) & XEL_RSR_RECV_DONE_MASK) || (xemaclite_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 = xemaclite_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; xemaclite_writel(tx_status, base_addr + XEL_TSR_OFFSET); tx_complete = true; } /* Check if the Transmission for the second buffer is completed */ tx_status = xemaclite_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; xemaclite_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 (xemaclite_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 = xemaclite_readl(lp->base_addr + XEL_MDIOCTRL_OFFSET); xemaclite_writel(XEL_MDIOADDR_OP_MASK | ((phy_id << XEL_MDIOADDR_PHYADR_SHIFT) | reg), lp->base_addr + XEL_MDIOADDR_OFFSET); xemaclite_writel(ctrl_reg | XEL_MDIOCTRL_MDIOSTS_MASK, lp->base_addr + XEL_MDIOCTRL_OFFSET); if (xemaclite_mdio_wait(lp)) return -ETIMEDOUT; rc = xemaclite_readl(lp->base_addr + XEL_MDIORD_OFFSET); dev_dbg(&lp->ndev->dev, "%s(phy_id=%i, reg=%x) == %x\n", __func__, 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. * * Return: 0 upon success or a negative error upon failure */ 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, "%s(phy_id=%i, reg=%x, val=%x)\n", __func__, 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 = xemaclite_readl(lp->base_addr + XEL_MDIOCTRL_OFFSET); xemaclite_writel(~XEL_MDIOADDR_OP_MASK & ((phy_id << XEL_MDIOADDR_PHYADR_SHIFT) | reg), lp->base_addr + XEL_MDIOADDR_OFFSET); xemaclite_writel(val, lp->base_addr + XEL_MDIOWR_OFFSET); xemaclite_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 * @dev: 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; struct resource res; struct device_node *np = of_get_parent(lp->phy_node); struct device_node *npp; int rc, ret; /* 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); ret = of_address_to_resource(npp, 0, &res); of_node_put(npp); if (ret) { dev_err(dev, "%s resource error!\n", dev->of_node->full_name); of_node_put(np); return ret; } 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"); else put_device(&phydev->mdio.dev); of_node_put(np); return 0; } /* Enable the MDIO bus by asserting the enable bit in MDIO Control * register. */ xemaclite_writel(XEL_MDIOCTRL_MDIOEN_MASK, lp->base_addr + XEL_MDIOCTRL_OFFSET); bus = mdiobus_alloc(); if (!bus) { dev_err(dev, "Failed to allocate mdiobus\n"); of_node_put(np); 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; rc = of_mdiobus_register(bus, np); of_node_put(np); if (rc) { dev_err(dev, "Failed to register mdio bus.\n"); goto err_register; } lp->mii_bus = bus; 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. * * Return: 0 on success. -ENODEV, if PHY cannot be connected. * Non-zero error value on failure. */ 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. * * Return: 0, always. */ 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: NETDEV_TX_OK, always. */ static netdev_tx_t 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 NETDEV_TX_OK; } spin_unlock_irqrestore(&lp->reset_lock, flags); skb_tx_timestamp(new_skb); dev->stats.tx_bytes += len; dev_consume_skb_any(new_skb); return NETDEV_TX_OK; } /** * 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) { dev_warn(&ofdev->dev, "Parameter %s not found, defaulting to false\n", s); return false; } return (bool)*p; } static const struct net_device_ops xemaclite_netdev_ops; /** * xemaclite_of_probe - Probe method for the Emaclite device. * @ofdev: Pointer to OF device structure * * 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, using random\n"); eth_hw_addr_random(ndev); } /* Clear the Tx CSR's in case this is a restart */ xemaclite_writel(0, lp->base_addr + XEL_TSR_OFFSET); xemaclite_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); xemaclite_mdio_setup(lp, &ofdev->dev); 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 put_node; } dev_info(dev, "Xilinx EmacLite at 0x%08X mapped to 0x%p, irq=%d\n", (unsigned int __force)ndev->mem_start, lp->base_addr, ndev->irq); return 0; put_node: of_node_put(lp->phy_node); error: free_netdev(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->mii_bus) { mdiobus_unregister(lp->mii_bus); mdiobus_free(lp->mii_bus); lp->mii_bus = NULL; } unregister_netdev(ndev); of_node_put(lp->phy_node); lp->phy_node = NULL; free_netdev(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 const 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");