/* Altera Triple-Speed Ethernet MAC driver * Copyright (C) 2008-2014 Altera Corporation. All rights reserved * * Contributors: * Dalon Westergreen * Thomas Chou * Ian Abbott * Yuriy Kozlov * Tobias Klauser * Andriy Smolskyy * Roman Bulgakov * Dmytro Mytarchuk * Matthew Gerlach * * Original driver contributed by SLS. * Major updates contributed by GlobalLogic * * This program is free software; you can redistribute it and/or modify it * under the terms and conditions of the GNU General Public License, * version 2, as published by the Free Software Foundation. * * This program is distributed in the hope it will be useful, but WITHOUT * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for * more details. * * You should have received a copy of the GNU General Public License along with * this program. If not, see . */ #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include "altera_utils.h" #include "altera_tse.h" #include "altera_sgdma.h" #include "altera_msgdma.h" static atomic_t instance_count = ATOMIC_INIT(~0); /* Module parameters */ static int debug = -1; module_param(debug, int, S_IRUGO | S_IWUSR); MODULE_PARM_DESC(debug, "Message Level (-1: default, 0: no output, 16: all)"); static const u32 default_msg_level = (NETIF_MSG_DRV | NETIF_MSG_PROBE | NETIF_MSG_LINK | NETIF_MSG_IFUP | NETIF_MSG_IFDOWN); #define RX_DESCRIPTORS 64 static int dma_rx_num = RX_DESCRIPTORS; module_param(dma_rx_num, int, S_IRUGO | S_IWUSR); MODULE_PARM_DESC(dma_rx_num, "Number of descriptors in the RX list"); #define TX_DESCRIPTORS 64 static int dma_tx_num = TX_DESCRIPTORS; module_param(dma_tx_num, int, S_IRUGO | S_IWUSR); MODULE_PARM_DESC(dma_tx_num, "Number of descriptors in the TX list"); #define POLL_PHY (-1) /* Make sure DMA buffer size is larger than the max frame size * plus some alignment offset and a VLAN header. If the max frame size is * 1518, a VLAN header would be additional 4 bytes and additional * headroom for alignment is 2 bytes, 2048 is just fine. */ #define ALTERA_RXDMABUFFER_SIZE 2048 /* Allow network stack to resume queueing packets after we've * finished transmitting at least 1/4 of the packets in the queue. */ #define TSE_TX_THRESH(x) (x->tx_ring_size / 4) #define TXQUEUESTOP_THRESHHOLD 2 static const struct of_device_id altera_tse_ids[]; static inline u32 tse_tx_avail(struct altera_tse_private *priv) { return priv->tx_cons + priv->tx_ring_size - priv->tx_prod - 1; } /* MDIO specific functions */ static int altera_tse_mdio_read(struct mii_bus *bus, int mii_id, int regnum) { struct net_device *ndev = bus->priv; struct altera_tse_private *priv = netdev_priv(ndev); /* set MDIO address */ csrwr32((mii_id & 0x1f), priv->mac_dev, tse_csroffs(mdio_phy1_addr)); /* get the data */ return csrrd32(priv->mac_dev, tse_csroffs(mdio_phy1) + regnum * 4) & 0xffff; } static int altera_tse_mdio_write(struct mii_bus *bus, int mii_id, int regnum, u16 value) { struct net_device *ndev = bus->priv; struct altera_tse_private *priv = netdev_priv(ndev); /* set MDIO address */ csrwr32((mii_id & 0x1f), priv->mac_dev, tse_csroffs(mdio_phy1_addr)); /* write the data */ csrwr32(value, priv->mac_dev, tse_csroffs(mdio_phy1) + regnum * 4); return 0; } static int altera_tse_mdio_create(struct net_device *dev, unsigned int id) { struct altera_tse_private *priv = netdev_priv(dev); int ret; struct device_node *mdio_node = NULL; struct mii_bus *mdio = NULL; struct device_node *child_node = NULL; for_each_child_of_node(priv->device->of_node, child_node) { if (of_device_is_compatible(child_node, "altr,tse-mdio")) { mdio_node = child_node; break; } } if (mdio_node) { netdev_dbg(dev, "FOUND MDIO subnode\n"); } else { netdev_dbg(dev, "NO MDIO subnode\n"); return 0; } mdio = mdiobus_alloc(); if (mdio == NULL) { netdev_err(dev, "Error allocating MDIO bus\n"); return -ENOMEM; } mdio->name = ALTERA_TSE_RESOURCE_NAME; mdio->read = &altera_tse_mdio_read; mdio->write = &altera_tse_mdio_write; snprintf(mdio->id, MII_BUS_ID_SIZE, "%s-%u", mdio->name, id); mdio->priv = dev; mdio->parent = priv->device; ret = of_mdiobus_register(mdio, mdio_node); if (ret != 0) { netdev_err(dev, "Cannot register MDIO bus %s\n", mdio->id); goto out_free_mdio; } if (netif_msg_drv(priv)) netdev_info(dev, "MDIO bus %s: created\n", mdio->id); priv->mdio = mdio; return 0; out_free_mdio: mdiobus_free(mdio); mdio = NULL; return ret; } static void altera_tse_mdio_destroy(struct net_device *dev) { struct altera_tse_private *priv = netdev_priv(dev); if (priv->mdio == NULL) return; if (netif_msg_drv(priv)) netdev_info(dev, "MDIO bus %s: removed\n", priv->mdio->id); mdiobus_unregister(priv->mdio); kfree(priv->mdio->irq); mdiobus_free(priv->mdio); priv->mdio = NULL; } static int tse_init_rx_buffer(struct altera_tse_private *priv, struct tse_buffer *rxbuffer, int len) { rxbuffer->skb = netdev_alloc_skb_ip_align(priv->dev, len); if (!rxbuffer->skb) return -ENOMEM; rxbuffer->dma_addr = dma_map_single(priv->device, rxbuffer->skb->data, len, DMA_FROM_DEVICE); if (dma_mapping_error(priv->device, rxbuffer->dma_addr)) { netdev_err(priv->dev, "%s: DMA mapping error\n", __func__); dev_kfree_skb_any(rxbuffer->skb); return -EINVAL; } rxbuffer->dma_addr &= (dma_addr_t)~3; rxbuffer->len = len; return 0; } static void tse_free_rx_buffer(struct altera_tse_private *priv, struct tse_buffer *rxbuffer) { struct sk_buff *skb = rxbuffer->skb; dma_addr_t dma_addr = rxbuffer->dma_addr; if (skb != NULL) { if (dma_addr) dma_unmap_single(priv->device, dma_addr, rxbuffer->len, DMA_FROM_DEVICE); dev_kfree_skb_any(skb); rxbuffer->skb = NULL; rxbuffer->dma_addr = 0; } } /* Unmap and free Tx buffer resources */ static void tse_free_tx_buffer(struct altera_tse_private *priv, struct tse_buffer *buffer) { if (buffer->dma_addr) { if (buffer->mapped_as_page) dma_unmap_page(priv->device, buffer->dma_addr, buffer->len, DMA_TO_DEVICE); else dma_unmap_single(priv->device, buffer->dma_addr, buffer->len, DMA_TO_DEVICE); buffer->dma_addr = 0; } if (buffer->skb) { dev_kfree_skb_any(buffer->skb); buffer->skb = NULL; } } static int alloc_init_skbufs(struct altera_tse_private *priv) { unsigned int rx_descs = priv->rx_ring_size; unsigned int tx_descs = priv->tx_ring_size; int ret = -ENOMEM; int i; /* Create Rx ring buffer */ priv->rx_ring = kcalloc(rx_descs, sizeof(struct tse_buffer), GFP_KERNEL); if (!priv->rx_ring) goto err_rx_ring; /* Create Tx ring buffer */ priv->tx_ring = kcalloc(tx_descs, sizeof(struct tse_buffer), GFP_KERNEL); if (!priv->tx_ring) goto err_tx_ring; priv->tx_cons = 0; priv->tx_prod = 0; /* Init Rx ring */ for (i = 0; i < rx_descs; i++) { ret = tse_init_rx_buffer(priv, &priv->rx_ring[i], priv->rx_dma_buf_sz); if (ret) goto err_init_rx_buffers; } priv->rx_cons = 0; priv->rx_prod = 0; return 0; err_init_rx_buffers: while (--i >= 0) tse_free_rx_buffer(priv, &priv->rx_ring[i]); kfree(priv->tx_ring); err_tx_ring: kfree(priv->rx_ring); err_rx_ring: return ret; } static void free_skbufs(struct net_device *dev) { struct altera_tse_private *priv = netdev_priv(dev); unsigned int rx_descs = priv->rx_ring_size; unsigned int tx_descs = priv->tx_ring_size; int i; /* Release the DMA TX/RX socket buffers */ for (i = 0; i < rx_descs; i++) tse_free_rx_buffer(priv, &priv->rx_ring[i]); for (i = 0; i < tx_descs; i++) tse_free_tx_buffer(priv, &priv->tx_ring[i]); kfree(priv->tx_ring); } /* Reallocate the skb for the reception process */ static inline void tse_rx_refill(struct altera_tse_private *priv) { unsigned int rxsize = priv->rx_ring_size; unsigned int entry; int ret; for (; priv->rx_cons - priv->rx_prod > 0; priv->rx_prod++) { entry = priv->rx_prod % rxsize; if (likely(priv->rx_ring[entry].skb == NULL)) { ret = tse_init_rx_buffer(priv, &priv->rx_ring[entry], priv->rx_dma_buf_sz); if (unlikely(ret != 0)) break; priv->dmaops->add_rx_desc(priv, &priv->rx_ring[entry]); } } } /* Pull out the VLAN tag and fix up the packet */ static inline void tse_rx_vlan(struct net_device *dev, struct sk_buff *skb) { struct ethhdr *eth_hdr; u16 vid; if ((dev->features & NETIF_F_HW_VLAN_CTAG_RX) && !__vlan_get_tag(skb, &vid)) { eth_hdr = (struct ethhdr *)skb->data; memmove(skb->data + VLAN_HLEN, eth_hdr, ETH_ALEN * 2); skb_pull(skb, VLAN_HLEN); __vlan_hwaccel_put_tag(skb, htons(ETH_P_8021Q), vid); } } /* Receive a packet: retrieve and pass over to upper levels */ static int tse_rx(struct altera_tse_private *priv, int limit) { unsigned int count = 0; unsigned int next_entry; struct sk_buff *skb; unsigned int entry = priv->rx_cons % priv->rx_ring_size; u32 rxstatus; u16 pktlength; u16 pktstatus; /* Check for count < limit first as get_rx_status is changing * the response-fifo so we must process the next packet * after calling get_rx_status if a response is pending. * (reading the last byte of the response pops the value from the fifo.) */ while ((count < limit) && ((rxstatus = priv->dmaops->get_rx_status(priv)) != 0)) { pktstatus = rxstatus >> 16; pktlength = rxstatus & 0xffff; if ((pktstatus & 0xFF) || (pktlength == 0)) netdev_err(priv->dev, "RCV pktstatus %08X pktlength %08X\n", pktstatus, pktlength); /* DMA trasfer from TSE starts with 2 aditional bytes for * IP payload alignment. Status returned by get_rx_status() * contains DMA transfer length. Packet is 2 bytes shorter. */ pktlength -= 2; count++; next_entry = (++priv->rx_cons) % priv->rx_ring_size; skb = priv->rx_ring[entry].skb; if (unlikely(!skb)) { netdev_err(priv->dev, "%s: Inconsistent Rx descriptor chain\n", __func__); priv->dev->stats.rx_dropped++; break; } priv->rx_ring[entry].skb = NULL; skb_put(skb, pktlength); /* make cache consistent with receive packet buffer */ dma_sync_single_for_cpu(priv->device, priv->rx_ring[entry].dma_addr, priv->rx_ring[entry].len, DMA_FROM_DEVICE); dma_unmap_single(priv->device, priv->rx_ring[entry].dma_addr, priv->rx_ring[entry].len, DMA_FROM_DEVICE); if (netif_msg_pktdata(priv)) { netdev_info(priv->dev, "frame received %d bytes\n", pktlength); print_hex_dump(KERN_ERR, "data: ", DUMP_PREFIX_OFFSET, 16, 1, skb->data, pktlength, true); } tse_rx_vlan(priv->dev, skb); skb->protocol = eth_type_trans(skb, priv->dev); skb_checksum_none_assert(skb); napi_gro_receive(&priv->napi, skb); priv->dev->stats.rx_packets++; priv->dev->stats.rx_bytes += pktlength; entry = next_entry; tse_rx_refill(priv); } return count; } /* Reclaim resources after transmission completes */ static int tse_tx_complete(struct altera_tse_private *priv) { unsigned int txsize = priv->tx_ring_size; u32 ready; unsigned int entry; struct tse_buffer *tx_buff; int txcomplete = 0; spin_lock(&priv->tx_lock); ready = priv->dmaops->tx_completions(priv); /* Free sent buffers */ while (ready && (priv->tx_cons != priv->tx_prod)) { entry = priv->tx_cons % txsize; tx_buff = &priv->tx_ring[entry]; if (netif_msg_tx_done(priv)) netdev_dbg(priv->dev, "%s: curr %d, dirty %d\n", __func__, priv->tx_prod, priv->tx_cons); if (likely(tx_buff->skb)) priv->dev->stats.tx_packets++; tse_free_tx_buffer(priv, tx_buff); priv->tx_cons++; txcomplete++; ready--; } if (unlikely(netif_queue_stopped(priv->dev) && tse_tx_avail(priv) > TSE_TX_THRESH(priv))) { netif_tx_lock(priv->dev); if (netif_queue_stopped(priv->dev) && tse_tx_avail(priv) > TSE_TX_THRESH(priv)) { if (netif_msg_tx_done(priv)) netdev_dbg(priv->dev, "%s: restart transmit\n", __func__); netif_wake_queue(priv->dev); } netif_tx_unlock(priv->dev); } spin_unlock(&priv->tx_lock); return txcomplete; } /* NAPI polling function */ static int tse_poll(struct napi_struct *napi, int budget) { struct altera_tse_private *priv = container_of(napi, struct altera_tse_private, napi); int rxcomplete = 0; unsigned long int flags; tse_tx_complete(priv); rxcomplete = tse_rx(priv, budget); if (rxcomplete < budget) { napi_complete(napi); netdev_dbg(priv->dev, "NAPI Complete, did %d packets with budget %d\n", rxcomplete, budget); spin_lock_irqsave(&priv->rxdma_irq_lock, flags); priv->dmaops->enable_rxirq(priv); priv->dmaops->enable_txirq(priv); spin_unlock_irqrestore(&priv->rxdma_irq_lock, flags); } return rxcomplete; } /* DMA TX & RX FIFO interrupt routing */ static irqreturn_t altera_isr(int irq, void *dev_id) { struct net_device *dev = dev_id; struct altera_tse_private *priv; if (unlikely(!dev)) { pr_err("%s: invalid dev pointer\n", __func__); return IRQ_NONE; } priv = netdev_priv(dev); spin_lock(&priv->rxdma_irq_lock); /* reset IRQs */ priv->dmaops->clear_rxirq(priv); priv->dmaops->clear_txirq(priv); spin_unlock(&priv->rxdma_irq_lock); if (likely(napi_schedule_prep(&priv->napi))) { spin_lock(&priv->rxdma_irq_lock); priv->dmaops->disable_rxirq(priv); priv->dmaops->disable_txirq(priv); spin_unlock(&priv->rxdma_irq_lock); __napi_schedule(&priv->napi); } return IRQ_HANDLED; } /* Transmit a packet (called by the kernel). Dispatches * either the SGDMA method for transmitting or the * MSGDMA method, assumes no scatter/gather support, * implying an assumption that there's only one * physically contiguous fragment starting at * skb->data, for length of skb_headlen(skb). */ static int tse_start_xmit(struct sk_buff *skb, struct net_device *dev) { struct altera_tse_private *priv = netdev_priv(dev); unsigned int txsize = priv->tx_ring_size; unsigned int entry; struct tse_buffer *buffer = NULL; int nfrags = skb_shinfo(skb)->nr_frags; unsigned int nopaged_len = skb_headlen(skb); enum netdev_tx ret = NETDEV_TX_OK; dma_addr_t dma_addr; spin_lock_bh(&priv->tx_lock); if (unlikely(tse_tx_avail(priv) < nfrags + 1)) { if (!netif_queue_stopped(dev)) { netif_stop_queue(dev); /* This is a hard error, log it. */ netdev_err(priv->dev, "%s: Tx list full when queue awake\n", __func__); } ret = NETDEV_TX_BUSY; goto out; } /* Map the first skb fragment */ entry = priv->tx_prod % txsize; buffer = &priv->tx_ring[entry]; dma_addr = dma_map_single(priv->device, skb->data, nopaged_len, DMA_TO_DEVICE); if (dma_mapping_error(priv->device, dma_addr)) { netdev_err(priv->dev, "%s: DMA mapping error\n", __func__); ret = NETDEV_TX_OK; goto out; } buffer->skb = skb; buffer->dma_addr = dma_addr; buffer->len = nopaged_len; /* Push data out of the cache hierarchy into main memory */ dma_sync_single_for_device(priv->device, buffer->dma_addr, buffer->len, DMA_TO_DEVICE); priv->dmaops->tx_buffer(priv, buffer); skb_tx_timestamp(skb); priv->tx_prod++; dev->stats.tx_bytes += skb->len; if (unlikely(tse_tx_avail(priv) <= TXQUEUESTOP_THRESHHOLD)) { if (netif_msg_hw(priv)) netdev_dbg(priv->dev, "%s: stop transmitted packets\n", __func__); netif_stop_queue(dev); } out: spin_unlock_bh(&priv->tx_lock); return ret; } /* Called every time the controller might need to be made * aware of new link state. The PHY code conveys this * information through variables in the phydev structure, and this * function converts those variables into the appropriate * register values, and can bring down the device if needed. */ static void altera_tse_adjust_link(struct net_device *dev) { struct altera_tse_private *priv = netdev_priv(dev); struct phy_device *phydev = priv->phydev; int new_state = 0; /* only change config if there is a link */ spin_lock(&priv->mac_cfg_lock); if (phydev->link) { /* Read old config */ u32 cfg_reg = ioread32(&priv->mac_dev->command_config); /* Check duplex */ if (phydev->duplex != priv->oldduplex) { new_state = 1; if (!(phydev->duplex)) cfg_reg |= MAC_CMDCFG_HD_ENA; else cfg_reg &= ~MAC_CMDCFG_HD_ENA; netdev_dbg(priv->dev, "%s: Link duplex = 0x%x\n", dev->name, phydev->duplex); priv->oldduplex = phydev->duplex; } /* Check speed */ if (phydev->speed != priv->oldspeed) { new_state = 1; switch (phydev->speed) { case 1000: cfg_reg |= MAC_CMDCFG_ETH_SPEED; cfg_reg &= ~MAC_CMDCFG_ENA_10; break; case 100: cfg_reg &= ~MAC_CMDCFG_ETH_SPEED; cfg_reg &= ~MAC_CMDCFG_ENA_10; break; case 10: cfg_reg &= ~MAC_CMDCFG_ETH_SPEED; cfg_reg |= MAC_CMDCFG_ENA_10; break; default: if (netif_msg_link(priv)) netdev_warn(dev, "Speed (%d) is not 10/100/1000!\n", phydev->speed); break; } priv->oldspeed = phydev->speed; } iowrite32(cfg_reg, &priv->mac_dev->command_config); if (!priv->oldlink) { new_state = 1; priv->oldlink = 1; } } else if (priv->oldlink) { new_state = 1; priv->oldlink = 0; priv->oldspeed = 0; priv->oldduplex = -1; } if (new_state && netif_msg_link(priv)) phy_print_status(phydev); spin_unlock(&priv->mac_cfg_lock); } static struct phy_device *connect_local_phy(struct net_device *dev) { struct altera_tse_private *priv = netdev_priv(dev); struct phy_device *phydev = NULL; char phy_id_fmt[MII_BUS_ID_SIZE + 3]; if (priv->phy_addr != POLL_PHY) { snprintf(phy_id_fmt, MII_BUS_ID_SIZE + 3, PHY_ID_FMT, priv->mdio->id, priv->phy_addr); netdev_dbg(dev, "trying to attach to %s\n", phy_id_fmt); phydev = phy_connect(dev, phy_id_fmt, &altera_tse_adjust_link, priv->phy_iface); if (IS_ERR(phydev)) netdev_err(dev, "Could not attach to PHY\n"); } else { int ret; phydev = phy_find_first(priv->mdio); if (phydev == NULL) { netdev_err(dev, "No PHY found\n"); return phydev; } ret = phy_connect_direct(dev, phydev, &altera_tse_adjust_link, priv->phy_iface); if (ret != 0) { netdev_err(dev, "Could not attach to PHY\n"); phydev = NULL; } } return phydev; } static int altera_tse_phy_get_addr_mdio_create(struct net_device *dev) { struct altera_tse_private *priv = netdev_priv(dev); struct device_node *np = priv->device->of_node; int ret = 0; priv->phy_iface = of_get_phy_mode(np); /* Avoid get phy addr and create mdio if no phy is present */ if (!priv->phy_iface) return 0; /* try to get PHY address from device tree, use PHY autodetection if * no valid address is given */ if (of_property_read_u32(priv->device->of_node, "phy-addr", &priv->phy_addr)) { priv->phy_addr = POLL_PHY; } if (!((priv->phy_addr == POLL_PHY) || ((priv->phy_addr >= 0) && (priv->phy_addr < PHY_MAX_ADDR)))) { netdev_err(dev, "invalid phy-addr specified %d\n", priv->phy_addr); return -ENODEV; } /* Create/attach to MDIO bus */ ret = altera_tse_mdio_create(dev, atomic_add_return(1, &instance_count)); if (ret) return -ENODEV; return 0; } /* Initialize driver's PHY state, and attach to the PHY */ static int init_phy(struct net_device *dev) { struct altera_tse_private *priv = netdev_priv(dev); struct phy_device *phydev; struct device_node *phynode; bool fixed_link = false; int rc = 0; /* Avoid init phy in case of no phy present */ if (!priv->phy_iface) return 0; priv->oldlink = 0; priv->oldspeed = 0; priv->oldduplex = -1; phynode = of_parse_phandle(priv->device->of_node, "phy-handle", 0); if (!phynode) { /* check if a fixed-link is defined in device-tree */ if (of_phy_is_fixed_link(priv->device->of_node)) { rc = of_phy_register_fixed_link(priv->device->of_node); if (rc < 0) { netdev_err(dev, "cannot register fixed PHY\n"); return rc; } /* In the case of a fixed PHY, the DT node associated * to the PHY is the Ethernet MAC DT node. */ phynode = of_node_get(priv->device->of_node); fixed_link = true; netdev_dbg(dev, "fixed-link detected\n"); phydev = of_phy_connect(dev, phynode, &altera_tse_adjust_link, 0, priv->phy_iface); } else { netdev_dbg(dev, "no phy-handle found\n"); if (!priv->mdio) { netdev_err(dev, "No phy-handle nor local mdio specified\n"); return -ENODEV; } phydev = connect_local_phy(dev); } } else { netdev_dbg(dev, "phy-handle found\n"); phydev = of_phy_connect(dev, phynode, &altera_tse_adjust_link, 0, priv->phy_iface); } if (!phydev) { netdev_err(dev, "Could not find the PHY\n"); return -ENODEV; } /* Stop Advertising 1000BASE Capability if interface is not GMII * Note: Checkpatch throws CHECKs for the camel case defines below, * it's ok to ignore. */ if ((priv->phy_iface == PHY_INTERFACE_MODE_MII) || (priv->phy_iface == PHY_INTERFACE_MODE_RMII)) phydev->advertising &= ~(SUPPORTED_1000baseT_Half | SUPPORTED_1000baseT_Full); /* Broken HW is sometimes missing the pull-up resistor on the * MDIO line, which results in reads to non-existent devices returning * 0 rather than 0xffff. Catch this here and treat 0 as a non-existent * device as well. If a fixed-link is used the phy_id is always 0. * Note: phydev->phy_id is the result of reading the UID PHY registers. */ if ((phydev->phy_id == 0) && !fixed_link) { netdev_err(dev, "Bad PHY UID 0x%08x\n", phydev->phy_id); phy_disconnect(phydev); return -ENODEV; } netdev_dbg(dev, "attached to PHY %d UID 0x%08x Link = %d\n", phydev->addr, phydev->phy_id, phydev->link); priv->phydev = phydev; return 0; } static void tse_update_mac_addr(struct altera_tse_private *priv, u8 *addr) { u32 msb; u32 lsb; msb = (addr[3] << 24) | (addr[2] << 16) | (addr[1] << 8) | addr[0]; lsb = ((addr[5] << 8) | addr[4]) & 0xffff; /* Set primary MAC address */ csrwr32(msb, priv->mac_dev, tse_csroffs(mac_addr_0)); csrwr32(lsb, priv->mac_dev, tse_csroffs(mac_addr_1)); } /* MAC software reset. * When reset is triggered, the MAC function completes the current * transmission or reception, and subsequently disables the transmit and * receive logic, flushes the receive FIFO buffer, and resets the statistics * counters. */ static int reset_mac(struct altera_tse_private *priv) { int counter; u32 dat; dat = csrrd32(priv->mac_dev, tse_csroffs(command_config)); dat &= ~(MAC_CMDCFG_TX_ENA | MAC_CMDCFG_RX_ENA); dat |= MAC_CMDCFG_SW_RESET | MAC_CMDCFG_CNT_RESET; csrwr32(dat, priv->mac_dev, tse_csroffs(command_config)); counter = 0; while (counter++ < ALTERA_TSE_SW_RESET_WATCHDOG_CNTR) { if (tse_bit_is_clear(priv->mac_dev, tse_csroffs(command_config), MAC_CMDCFG_SW_RESET)) break; udelay(1); } if (counter >= ALTERA_TSE_SW_RESET_WATCHDOG_CNTR) { dat = csrrd32(priv->mac_dev, tse_csroffs(command_config)); dat &= ~MAC_CMDCFG_SW_RESET; csrwr32(dat, priv->mac_dev, tse_csroffs(command_config)); return -1; } return 0; } /* Initialize MAC core registers */ static int init_mac(struct altera_tse_private *priv) { unsigned int cmd = 0; u32 frm_length; /* Setup Rx FIFO */ csrwr32(priv->rx_fifo_depth - ALTERA_TSE_RX_SECTION_EMPTY, priv->mac_dev, tse_csroffs(rx_section_empty)); csrwr32(ALTERA_TSE_RX_SECTION_FULL, priv->mac_dev, tse_csroffs(rx_section_full)); csrwr32(ALTERA_TSE_RX_ALMOST_EMPTY, priv->mac_dev, tse_csroffs(rx_almost_empty)); csrwr32(ALTERA_TSE_RX_ALMOST_FULL, priv->mac_dev, tse_csroffs(rx_almost_full)); /* Setup Tx FIFO */ csrwr32(priv->tx_fifo_depth - ALTERA_TSE_TX_SECTION_EMPTY, priv->mac_dev, tse_csroffs(tx_section_empty)); csrwr32(ALTERA_TSE_TX_SECTION_FULL, priv->mac_dev, tse_csroffs(tx_section_full)); csrwr32(ALTERA_TSE_TX_ALMOST_EMPTY, priv->mac_dev, tse_csroffs(tx_almost_empty)); csrwr32(ALTERA_TSE_TX_ALMOST_FULL, priv->mac_dev, tse_csroffs(tx_almost_full)); /* MAC Address Configuration */ tse_update_mac_addr(priv, priv->dev->dev_addr); /* MAC Function Configuration */ frm_length = ETH_HLEN + priv->dev->mtu + ETH_FCS_LEN; csrwr32(frm_length, priv->mac_dev, tse_csroffs(frm_length)); csrwr32(ALTERA_TSE_TX_IPG_LENGTH, priv->mac_dev, tse_csroffs(tx_ipg_length)); /* Disable RX/TX shift 16 for alignment of all received frames on 16-bit * start address */ tse_set_bit(priv->mac_dev, tse_csroffs(rx_cmd_stat), ALTERA_TSE_RX_CMD_STAT_RX_SHIFT16); tse_clear_bit(priv->mac_dev, tse_csroffs(tx_cmd_stat), ALTERA_TSE_TX_CMD_STAT_TX_SHIFT16 | ALTERA_TSE_TX_CMD_STAT_OMIT_CRC); /* Set the MAC options */ cmd = csrrd32(priv->mac_dev, tse_csroffs(command_config)); cmd &= ~MAC_CMDCFG_PAD_EN; /* No padding Removal on Receive */ cmd &= ~MAC_CMDCFG_CRC_FWD; /* CRC Removal */ cmd |= MAC_CMDCFG_RX_ERR_DISC; /* Automatically discard frames * with CRC errors */ cmd |= MAC_CMDCFG_CNTL_FRM_ENA; cmd &= ~MAC_CMDCFG_TX_ENA; cmd &= ~MAC_CMDCFG_RX_ENA; /* Default speed and duplex setting, full/100 */ cmd &= ~MAC_CMDCFG_HD_ENA; cmd &= ~MAC_CMDCFG_ETH_SPEED; cmd &= ~MAC_CMDCFG_ENA_10; csrwr32(cmd, priv->mac_dev, tse_csroffs(command_config)); csrwr32(ALTERA_TSE_PAUSE_QUANTA, priv->mac_dev, tse_csroffs(pause_quanta)); if (netif_msg_hw(priv)) dev_dbg(priv->device, "MAC post-initialization: CMD_CONFIG = 0x%08x\n", cmd); return 0; } /* Start/stop MAC transmission logic */ static void tse_set_mac(struct altera_tse_private *priv, bool enable) { u32 value = csrrd32(priv->mac_dev, tse_csroffs(command_config)); if (enable) value |= MAC_CMDCFG_TX_ENA | MAC_CMDCFG_RX_ENA; else value &= ~(MAC_CMDCFG_TX_ENA | MAC_CMDCFG_RX_ENA); csrwr32(value, priv->mac_dev, tse_csroffs(command_config)); } /* Change the MTU */ static int tse_change_mtu(struct net_device *dev, int new_mtu) { struct altera_tse_private *priv = netdev_priv(dev); unsigned int max_mtu = priv->max_mtu; unsigned int min_mtu = ETH_ZLEN + ETH_FCS_LEN; if (netif_running(dev)) { netdev_err(dev, "must be stopped to change its MTU\n"); return -EBUSY; } if ((new_mtu < min_mtu) || (new_mtu > max_mtu)) { netdev_err(dev, "invalid MTU, max MTU is: %u\n", max_mtu); return -EINVAL; } dev->mtu = new_mtu; netdev_update_features(dev); return 0; } static void altera_tse_set_mcfilter(struct net_device *dev) { struct altera_tse_private *priv = netdev_priv(dev); int i; struct netdev_hw_addr *ha; /* clear the hash filter */ for (i = 0; i < 64; i++) csrwr32(0, priv->mac_dev, tse_csroffs(hash_table) + i * 4); netdev_for_each_mc_addr(ha, dev) { unsigned int hash = 0; int mac_octet; for (mac_octet = 5; mac_octet >= 0; mac_octet--) { unsigned char xor_bit = 0; unsigned char octet = ha->addr[mac_octet]; unsigned int bitshift; for (bitshift = 0; bitshift < 8; bitshift++) xor_bit ^= ((octet >> bitshift) & 0x01); hash = (hash << 1) | xor_bit; } csrwr32(1, priv->mac_dev, tse_csroffs(hash_table) + hash * 4); } } static void altera_tse_set_mcfilterall(struct net_device *dev) { struct altera_tse_private *priv = netdev_priv(dev); int i; /* set the hash filter */ for (i = 0; i < 64; i++) csrwr32(1, priv->mac_dev, tse_csroffs(hash_table) + i * 4); } /* Set or clear the multicast filter for this adaptor */ static void tse_set_rx_mode_hashfilter(struct net_device *dev) { struct altera_tse_private *priv = netdev_priv(dev); spin_lock(&priv->mac_cfg_lock); if (dev->flags & IFF_PROMISC) tse_set_bit(priv->mac_dev, tse_csroffs(command_config), MAC_CMDCFG_PROMIS_EN); if (dev->flags & IFF_ALLMULTI) altera_tse_set_mcfilterall(dev); else altera_tse_set_mcfilter(dev); spin_unlock(&priv->mac_cfg_lock); } /* Set or clear the multicast filter for this adaptor */ static void tse_set_rx_mode(struct net_device *dev) { struct altera_tse_private *priv = netdev_priv(dev); spin_lock(&priv->mac_cfg_lock); if ((dev->flags & IFF_PROMISC) || (dev->flags & IFF_ALLMULTI) || !netdev_mc_empty(dev) || !netdev_uc_empty(dev)) tse_set_bit(priv->mac_dev, tse_csroffs(command_config), MAC_CMDCFG_PROMIS_EN); else tse_clear_bit(priv->mac_dev, tse_csroffs(command_config), MAC_CMDCFG_PROMIS_EN); spin_unlock(&priv->mac_cfg_lock); } /* Open and initialize the interface */ static int tse_open(struct net_device *dev) { struct altera_tse_private *priv = netdev_priv(dev); int ret = 0; int i; unsigned long int flags; /* Reset and configure TSE MAC and probe associated PHY */ ret = priv->dmaops->init_dma(priv); if (ret != 0) { netdev_err(dev, "Cannot initialize DMA\n"); goto phy_error; } if (netif_msg_ifup(priv)) netdev_warn(dev, "device MAC address %pM\n", dev->dev_addr); if ((priv->revision < 0xd00) || (priv->revision > 0xe00)) netdev_warn(dev, "TSE revision %x\n", priv->revision); spin_lock(&priv->mac_cfg_lock); ret = reset_mac(priv); /* Note that reset_mac will fail if the clocks are gated by the PHY * due to the PHY being put into isolation or power down mode. * This is not an error if reset fails due to no clock. */ if (ret) netdev_dbg(dev, "Cannot reset MAC core (error: %d)\n", ret); ret = init_mac(priv); spin_unlock(&priv->mac_cfg_lock); if (ret) { netdev_err(dev, "Cannot init MAC core (error: %d)\n", ret); goto alloc_skbuf_error; } priv->dmaops->reset_dma(priv); /* Create and initialize the TX/RX descriptors chains. */ priv->rx_ring_size = dma_rx_num; priv->tx_ring_size = dma_tx_num; ret = alloc_init_skbufs(priv); if (ret) { netdev_err(dev, "DMA descriptors initialization failed\n"); goto alloc_skbuf_error; } /* Register RX interrupt */ ret = request_irq(priv->rx_irq, altera_isr, IRQF_SHARED, dev->name, dev); if (ret) { netdev_err(dev, "Unable to register RX interrupt %d\n", priv->rx_irq); goto init_error; } /* Register TX interrupt */ ret = request_irq(priv->tx_irq, altera_isr, IRQF_SHARED, dev->name, dev); if (ret) { netdev_err(dev, "Unable to register TX interrupt %d\n", priv->tx_irq); goto tx_request_irq_error; } /* Enable DMA interrupts */ spin_lock_irqsave(&priv->rxdma_irq_lock, flags); priv->dmaops->enable_rxirq(priv); priv->dmaops->enable_txirq(priv); /* Setup RX descriptor chain */ for (i = 0; i < priv->rx_ring_size; i++) priv->dmaops->add_rx_desc(priv, &priv->rx_ring[i]); spin_unlock_irqrestore(&priv->rxdma_irq_lock, flags); if (priv->phydev) phy_start(priv->phydev); napi_enable(&priv->napi); netif_start_queue(dev); priv->dmaops->start_rxdma(priv); /* Start MAC Rx/Tx */ spin_lock(&priv->mac_cfg_lock); tse_set_mac(priv, true); spin_unlock(&priv->mac_cfg_lock); return 0; tx_request_irq_error: free_irq(priv->rx_irq, dev); init_error: free_skbufs(dev); alloc_skbuf_error: phy_error: return ret; } /* Stop TSE MAC interface and put the device in an inactive state */ static int tse_shutdown(struct net_device *dev) { struct altera_tse_private *priv = netdev_priv(dev); int ret; unsigned long int flags; /* Stop the PHY */ if (priv->phydev) phy_stop(priv->phydev); netif_stop_queue(dev); napi_disable(&priv->napi); /* Disable DMA interrupts */ spin_lock_irqsave(&priv->rxdma_irq_lock, flags); priv->dmaops->disable_rxirq(priv); priv->dmaops->disable_txirq(priv); spin_unlock_irqrestore(&priv->rxdma_irq_lock, flags); /* Free the IRQ lines */ free_irq(priv->rx_irq, dev); free_irq(priv->tx_irq, dev); /* disable and reset the MAC, empties fifo */ spin_lock(&priv->mac_cfg_lock); spin_lock(&priv->tx_lock); ret = reset_mac(priv); /* Note that reset_mac will fail if the clocks are gated by the PHY * due to the PHY being put into isolation or power down mode. * This is not an error if reset fails due to no clock. */ if (ret) netdev_dbg(dev, "Cannot reset MAC core (error: %d)\n", ret); priv->dmaops->reset_dma(priv); free_skbufs(dev); spin_unlock(&priv->tx_lock); spin_unlock(&priv->mac_cfg_lock); priv->dmaops->uninit_dma(priv); return 0; } static struct net_device_ops altera_tse_netdev_ops = { .ndo_open = tse_open, .ndo_stop = tse_shutdown, .ndo_start_xmit = tse_start_xmit, .ndo_set_mac_address = eth_mac_addr, .ndo_set_rx_mode = tse_set_rx_mode, .ndo_change_mtu = tse_change_mtu, .ndo_validate_addr = eth_validate_addr, }; static int request_and_map(struct platform_device *pdev, const char *name, struct resource **res, void __iomem **ptr) { struct resource *region; struct device *device = &pdev->dev; *res = platform_get_resource_byname(pdev, IORESOURCE_MEM, name); if (*res == NULL) { dev_err(device, "resource %s not defined\n", name); return -ENODEV; } region = devm_request_mem_region(device, (*res)->start, resource_size(*res), dev_name(device)); if (region == NULL) { dev_err(device, "unable to request %s\n", name); return -EBUSY; } *ptr = devm_ioremap_nocache(device, region->start, resource_size(region)); if (*ptr == NULL) { dev_err(device, "ioremap_nocache of %s failed!", name); return -ENOMEM; } return 0; } /* Probe Altera TSE MAC device */ static int altera_tse_probe(struct platform_device *pdev) { struct net_device *ndev; int ret = -ENODEV; struct resource *control_port; struct resource *dma_res; struct altera_tse_private *priv; const unsigned char *macaddr; void __iomem *descmap; const struct of_device_id *of_id = NULL; ndev = alloc_etherdev(sizeof(struct altera_tse_private)); if (!ndev) { dev_err(&pdev->dev, "Could not allocate network device\n"); return -ENODEV; } SET_NETDEV_DEV(ndev, &pdev->dev); priv = netdev_priv(ndev); priv->device = &pdev->dev; priv->dev = ndev; priv->msg_enable = netif_msg_init(debug, default_msg_level); of_id = of_match_device(altera_tse_ids, &pdev->dev); if (of_id) priv->dmaops = (struct altera_dmaops *)of_id->data; if (priv->dmaops && priv->dmaops->altera_dtype == ALTERA_DTYPE_SGDMA) { /* Get the mapped address to the SGDMA descriptor memory */ ret = request_and_map(pdev, "s1", &dma_res, &descmap); if (ret) goto err_free_netdev; /* Start of that memory is for transmit descriptors */ priv->tx_dma_desc = descmap; /* First half is for tx descriptors, other half for tx */ priv->txdescmem = resource_size(dma_res)/2; priv->txdescmem_busaddr = (dma_addr_t)dma_res->start; priv->rx_dma_desc = (void __iomem *)((uintptr_t)(descmap + priv->txdescmem)); priv->rxdescmem = resource_size(dma_res)/2; priv->rxdescmem_busaddr = dma_res->start; priv->rxdescmem_busaddr += priv->txdescmem; if (upper_32_bits(priv->rxdescmem_busaddr)) { dev_dbg(priv->device, "SGDMA bus addresses greater than 32-bits\n"); goto err_free_netdev; } if (upper_32_bits(priv->txdescmem_busaddr)) { dev_dbg(priv->device, "SGDMA bus addresses greater than 32-bits\n"); goto err_free_netdev; } } else if (priv->dmaops && priv->dmaops->altera_dtype == ALTERA_DTYPE_MSGDMA) { ret = request_and_map(pdev, "rx_resp", &dma_res, &priv->rx_dma_resp); if (ret) goto err_free_netdev; ret = request_and_map(pdev, "tx_desc", &dma_res, &priv->tx_dma_desc); if (ret) goto err_free_netdev; priv->txdescmem = resource_size(dma_res); priv->txdescmem_busaddr = dma_res->start; ret = request_and_map(pdev, "rx_desc", &dma_res, &priv->rx_dma_desc); if (ret) goto err_free_netdev; priv->rxdescmem = resource_size(dma_res); priv->rxdescmem_busaddr = dma_res->start; } else { goto err_free_netdev; } if (!dma_set_mask(priv->device, DMA_BIT_MASK(priv->dmaops->dmamask))) dma_set_coherent_mask(priv->device, DMA_BIT_MASK(priv->dmaops->dmamask)); else if (!dma_set_mask(priv->device, DMA_BIT_MASK(32))) dma_set_coherent_mask(priv->device, DMA_BIT_MASK(32)); else goto err_free_netdev; /* MAC address space */ ret = request_and_map(pdev, "control_port", &control_port, (void __iomem **)&priv->mac_dev); if (ret) goto err_free_netdev; /* xSGDMA Rx Dispatcher address space */ ret = request_and_map(pdev, "rx_csr", &dma_res, &priv->rx_dma_csr); if (ret) goto err_free_netdev; /* xSGDMA Tx Dispatcher address space */ ret = request_and_map(pdev, "tx_csr", &dma_res, &priv->tx_dma_csr); if (ret) goto err_free_netdev; /* Rx IRQ */ priv->rx_irq = platform_get_irq_byname(pdev, "rx_irq"); if (priv->rx_irq == -ENXIO) { dev_err(&pdev->dev, "cannot obtain Rx IRQ\n"); ret = -ENXIO; goto err_free_netdev; } /* Tx IRQ */ priv->tx_irq = platform_get_irq_byname(pdev, "tx_irq"); if (priv->tx_irq == -ENXIO) { dev_err(&pdev->dev, "cannot obtain Tx IRQ\n"); ret = -ENXIO; goto err_free_netdev; } /* get FIFO depths from device tree */ if (of_property_read_u32(pdev->dev.of_node, "rx-fifo-depth", &priv->rx_fifo_depth)) { dev_err(&pdev->dev, "cannot obtain rx-fifo-depth\n"); ret = -ENXIO; goto err_free_netdev; } if (of_property_read_u32(pdev->dev.of_node, "tx-fifo-depth", &priv->tx_fifo_depth)) { dev_err(&pdev->dev, "cannot obtain tx-fifo-depth\n"); ret = -ENXIO; goto err_free_netdev; } /* get hash filter settings for this instance */ priv->hash_filter = of_property_read_bool(pdev->dev.of_node, "altr,has-hash-multicast-filter"); /* Set hash filter to not set for now until the * multicast filter receive issue is debugged */ priv->hash_filter = 0; /* get supplemental address settings for this instance */ priv->added_unicast = of_property_read_bool(pdev->dev.of_node, "altr,has-supplementary-unicast"); /* Max MTU is 1500, ETH_DATA_LEN */ priv->max_mtu = ETH_DATA_LEN; /* Get the max mtu from the device tree. Note that the * "max-frame-size" parameter is actually max mtu. Definition * in the ePAPR v1.1 spec and usage differ, so go with usage. */ of_property_read_u32(pdev->dev.of_node, "max-frame-size", &priv->max_mtu); /* The DMA buffer size already accounts for an alignment bias * to avoid unaligned access exceptions for the NIOS processor, */ priv->rx_dma_buf_sz = ALTERA_RXDMABUFFER_SIZE; /* get default MAC address from device tree */ macaddr = of_get_mac_address(pdev->dev.of_node); if (macaddr) ether_addr_copy(ndev->dev_addr, macaddr); else eth_hw_addr_random(ndev); /* get phy addr and create mdio */ ret = altera_tse_phy_get_addr_mdio_create(ndev); if (ret) goto err_free_netdev; /* initialize netdev */ ndev->mem_start = control_port->start; ndev->mem_end = control_port->end; ndev->netdev_ops = &altera_tse_netdev_ops; altera_tse_set_ethtool_ops(ndev); altera_tse_netdev_ops.ndo_set_rx_mode = tse_set_rx_mode; if (priv->hash_filter) altera_tse_netdev_ops.ndo_set_rx_mode = tse_set_rx_mode_hashfilter; /* Scatter/gather IO is not supported, * so it is turned off */ ndev->hw_features &= ~NETIF_F_SG; ndev->features |= ndev->hw_features | NETIF_F_HIGHDMA; /* VLAN offloading of tagging, stripping and filtering is not * supported by hardware, but driver will accommodate the * extra 4-byte VLAN tag for processing by upper layers */ ndev->features |= NETIF_F_HW_VLAN_CTAG_RX; /* setup NAPI interface */ netif_napi_add(ndev, &priv->napi, tse_poll, NAPI_POLL_WEIGHT); spin_lock_init(&priv->mac_cfg_lock); spin_lock_init(&priv->tx_lock); spin_lock_init(&priv->rxdma_irq_lock); netif_carrier_off(ndev); ret = register_netdev(ndev); if (ret) { dev_err(&pdev->dev, "failed to register TSE net device\n"); goto err_register_netdev; } platform_set_drvdata(pdev, ndev); priv->revision = ioread32(&priv->mac_dev->megacore_revision); if (netif_msg_probe(priv)) dev_info(&pdev->dev, "Altera TSE MAC version %d.%d at 0x%08lx irq %d/%d\n", (priv->revision >> 8) & 0xff, priv->revision & 0xff, (unsigned long) control_port->start, priv->rx_irq, priv->tx_irq); ret = init_phy(ndev); if (ret != 0) { netdev_err(ndev, "Cannot attach to PHY (error: %d)\n", ret); goto err_init_phy; } return 0; err_init_phy: unregister_netdev(ndev); err_register_netdev: netif_napi_del(&priv->napi); altera_tse_mdio_destroy(ndev); err_free_netdev: free_netdev(ndev); return ret; } /* Remove Altera TSE MAC device */ static int altera_tse_remove(struct platform_device *pdev) { struct net_device *ndev = platform_get_drvdata(pdev); struct altera_tse_private *priv = netdev_priv(ndev); if (priv->phydev) phy_disconnect(priv->phydev); platform_set_drvdata(pdev, NULL); altera_tse_mdio_destroy(ndev); unregister_netdev(ndev); free_netdev(ndev); return 0; } static const struct altera_dmaops altera_dtype_sgdma = { .altera_dtype = ALTERA_DTYPE_SGDMA, .dmamask = 32, .reset_dma = sgdma_reset, .enable_txirq = sgdma_enable_txirq, .enable_rxirq = sgdma_enable_rxirq, .disable_txirq = sgdma_disable_txirq, .disable_rxirq = sgdma_disable_rxirq, .clear_txirq = sgdma_clear_txirq, .clear_rxirq = sgdma_clear_rxirq, .tx_buffer = sgdma_tx_buffer, .tx_completions = sgdma_tx_completions, .add_rx_desc = sgdma_add_rx_desc, .get_rx_status = sgdma_rx_status, .init_dma = sgdma_initialize, .uninit_dma = sgdma_uninitialize, .start_rxdma = sgdma_start_rxdma, }; static const struct altera_dmaops altera_dtype_msgdma = { .altera_dtype = ALTERA_DTYPE_MSGDMA, .dmamask = 64, .reset_dma = msgdma_reset, .enable_txirq = msgdma_enable_txirq, .enable_rxirq = msgdma_enable_rxirq, .disable_txirq = msgdma_disable_txirq, .disable_rxirq = msgdma_disable_rxirq, .clear_txirq = msgdma_clear_txirq, .clear_rxirq = msgdma_clear_rxirq, .tx_buffer = msgdma_tx_buffer, .tx_completions = msgdma_tx_completions, .add_rx_desc = msgdma_add_rx_desc, .get_rx_status = msgdma_rx_status, .init_dma = msgdma_initialize, .uninit_dma = msgdma_uninitialize, .start_rxdma = msgdma_start_rxdma, }; static const struct of_device_id altera_tse_ids[] = { { .compatible = "altr,tse-msgdma-1.0", .data = &altera_dtype_msgdma, }, { .compatible = "altr,tse-1.0", .data = &altera_dtype_sgdma, }, { .compatible = "ALTR,tse-1.0", .data = &altera_dtype_sgdma, }, {}, }; MODULE_DEVICE_TABLE(of, altera_tse_ids); static struct platform_driver altera_tse_driver = { .probe = altera_tse_probe, .remove = altera_tse_remove, .suspend = NULL, .resume = NULL, .driver = { .name = ALTERA_TSE_RESOURCE_NAME, .of_match_table = altera_tse_ids, }, }; module_platform_driver(altera_tse_driver); MODULE_AUTHOR("Altera Corporation"); MODULE_DESCRIPTION("Altera Triple Speed Ethernet MAC driver"); MODULE_LICENSE("GPL v2");