Add the rt linux 4.1.3-rt3 as base
[kvmfornfv.git] / kernel / drivers / net / ethernet / korina.c
diff --git a/kernel/drivers/net/ethernet/korina.c b/kernel/drivers/net/ethernet/korina.c
new file mode 100644 (file)
index 0000000..d74f5f4
--- /dev/null
@@ -0,0 +1,1230 @@
+/*
+ *  Driver for the IDT RC32434 (Korina) on-chip ethernet controller.
+ *
+ *  Copyright 2004 IDT Inc. (rischelp@idt.com)
+ *  Copyright 2006 Felix Fietkau <nbd@openwrt.org>
+ *  Copyright 2008 Florian Fainelli <florian@openwrt.org>
+ *
+ *  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.
+ *
+ *  THIS  SOFTWARE  IS PROVIDED   ``AS  IS'' AND   ANY  EXPRESS OR IMPLIED
+ *  WARRANTIES,   INCLUDING, BUT NOT  LIMITED  TO, THE IMPLIED WARRANTIES OF
+ *  MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.  IN
+ *  NO  EVENT  SHALL   THE AUTHOR  BE    LIABLE FOR ANY   DIRECT, INDIRECT,
+ *  INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
+ *  NOT LIMITED   TO, PROCUREMENT OF  SUBSTITUTE GOODS  OR SERVICES; LOSS OF
+ *  USE, DATA,  OR PROFITS; OR  BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON
+ *  ANY THEORY OF LIABILITY, WHETHER IN  CONTRACT, STRICT LIABILITY, OR TORT
+ *  (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
+ *  THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ *
+ *  You should have received a copy of the  GNU General Public License along
+ *  with this program; if not, write  to the Free Software Foundation, Inc.,
+ *  675 Mass Ave, Cambridge, MA 02139, USA.
+ *
+ *  Writing to a DMA status register:
+ *
+ *  When writing to the status register, you should mask the bit you have
+ *  been testing the status register with. Both Tx and Rx DMA registers
+ *  should stick to this procedure.
+ */
+
+#include <linux/module.h>
+#include <linux/kernel.h>
+#include <linux/moduleparam.h>
+#include <linux/sched.h>
+#include <linux/ctype.h>
+#include <linux/types.h>
+#include <linux/interrupt.h>
+#include <linux/ioport.h>
+#include <linux/in.h>
+#include <linux/slab.h>
+#include <linux/string.h>
+#include <linux/delay.h>
+#include <linux/netdevice.h>
+#include <linux/etherdevice.h>
+#include <linux/skbuff.h>
+#include <linux/errno.h>
+#include <linux/platform_device.h>
+#include <linux/mii.h>
+#include <linux/ethtool.h>
+#include <linux/crc32.h>
+
+#include <asm/bootinfo.h>
+#include <asm/bitops.h>
+#include <asm/pgtable.h>
+#include <asm/io.h>
+#include <asm/dma.h>
+
+#include <asm/mach-rc32434/rb.h>
+#include <asm/mach-rc32434/rc32434.h>
+#include <asm/mach-rc32434/eth.h>
+#include <asm/mach-rc32434/dma_v.h>
+
+#define DRV_NAME        "korina"
+#define DRV_VERSION     "0.10"
+#define DRV_RELDATE     "04Mar2008"
+
+#define STATION_ADDRESS_HIGH(dev) (((dev)->dev_addr[0] << 8) | \
+                                  ((dev)->dev_addr[1]))
+#define STATION_ADDRESS_LOW(dev)  (((dev)->dev_addr[2] << 24) | \
+                                  ((dev)->dev_addr[3] << 16) | \
+                                  ((dev)->dev_addr[4] << 8)  | \
+                                  ((dev)->dev_addr[5]))
+
+#define MII_CLOCK 1250000      /* no more than 2.5MHz */
+
+/* the following must be powers of two */
+#define KORINA_NUM_RDS 64  /* number of receive descriptors */
+#define KORINA_NUM_TDS 64  /* number of transmit descriptors */
+
+/* KORINA_RBSIZE is the hardware's default maximum receive
+ * frame size in bytes. Having this hardcoded means that there
+ * is no support for MTU sizes greater than 1500. */
+#define KORINA_RBSIZE  1536 /* size of one resource buffer = Ether MTU */
+#define KORINA_RDS_MASK        (KORINA_NUM_RDS - 1)
+#define KORINA_TDS_MASK        (KORINA_NUM_TDS - 1)
+#define RD_RING_SIZE   (KORINA_NUM_RDS * sizeof(struct dma_desc))
+#define TD_RING_SIZE   (KORINA_NUM_TDS * sizeof(struct dma_desc))
+
+#define TX_TIMEOUT     (6000 * HZ / 1000)
+
+enum chain_status { desc_filled, desc_empty };
+#define IS_DMA_FINISHED(X)   (((X) & (DMA_DESC_FINI)) != 0)
+#define IS_DMA_DONE(X)   (((X) & (DMA_DESC_DONE)) != 0)
+#define RCVPKT_LENGTH(X)     (((X) & ETH_RX_LEN) >> ETH_RX_LEN_BIT)
+
+/* Information that need to be kept for each board. */
+struct korina_private {
+       struct eth_regs *eth_regs;
+       struct dma_reg *rx_dma_regs;
+       struct dma_reg *tx_dma_regs;
+       struct dma_desc *td_ring; /* transmit descriptor ring */
+       struct dma_desc *rd_ring; /* receive descriptor ring  */
+
+       struct sk_buff *tx_skb[KORINA_NUM_TDS];
+       struct sk_buff *rx_skb[KORINA_NUM_RDS];
+
+       int rx_next_done;
+       int rx_chain_head;
+       int rx_chain_tail;
+       enum chain_status rx_chain_status;
+
+       int tx_next_done;
+       int tx_chain_head;
+       int tx_chain_tail;
+       enum chain_status tx_chain_status;
+       int tx_count;
+       int tx_full;
+
+       int rx_irq;
+       int tx_irq;
+       int ovr_irq;
+       int und_irq;
+
+       spinlock_t lock;        /* NIC xmit lock */
+
+       int dma_halt_cnt;
+       int dma_run_cnt;
+       struct napi_struct napi;
+       struct timer_list media_check_timer;
+       struct mii_if_info mii_if;
+       struct work_struct restart_task;
+       struct net_device *dev;
+       int phy_addr;
+};
+
+extern unsigned int idt_cpu_freq;
+
+static inline void korina_start_dma(struct dma_reg *ch, u32 dma_addr)
+{
+       writel(0, &ch->dmandptr);
+       writel(dma_addr, &ch->dmadptr);
+}
+
+static inline void korina_abort_dma(struct net_device *dev,
+                                       struct dma_reg *ch)
+{
+       if (readl(&ch->dmac) & DMA_CHAN_RUN_BIT) {
+              writel(0x10, &ch->dmac);
+
+              while (!(readl(&ch->dmas) & DMA_STAT_HALT))
+                      dev->trans_start = jiffies;
+
+              writel(0, &ch->dmas);
+       }
+
+       writel(0, &ch->dmadptr);
+       writel(0, &ch->dmandptr);
+}
+
+static inline void korina_chain_dma(struct dma_reg *ch, u32 dma_addr)
+{
+       writel(dma_addr, &ch->dmandptr);
+}
+
+static void korina_abort_tx(struct net_device *dev)
+{
+       struct korina_private *lp = netdev_priv(dev);
+
+       korina_abort_dma(dev, lp->tx_dma_regs);
+}
+
+static void korina_abort_rx(struct net_device *dev)
+{
+       struct korina_private *lp = netdev_priv(dev);
+
+       korina_abort_dma(dev, lp->rx_dma_regs);
+}
+
+static void korina_start_rx(struct korina_private *lp,
+                                       struct dma_desc *rd)
+{
+       korina_start_dma(lp->rx_dma_regs, CPHYSADDR(rd));
+}
+
+static void korina_chain_rx(struct korina_private *lp,
+                                       struct dma_desc *rd)
+{
+       korina_chain_dma(lp->rx_dma_regs, CPHYSADDR(rd));
+}
+
+/* transmit packet */
+static int korina_send_packet(struct sk_buff *skb, struct net_device *dev)
+{
+       struct korina_private *lp = netdev_priv(dev);
+       unsigned long flags;
+       u32 length;
+       u32 chain_prev, chain_next;
+       struct dma_desc *td;
+
+       spin_lock_irqsave(&lp->lock, flags);
+
+       td = &lp->td_ring[lp->tx_chain_tail];
+
+       /* stop queue when full, drop pkts if queue already full */
+       if (lp->tx_count >= (KORINA_NUM_TDS - 2)) {
+               lp->tx_full = 1;
+
+               if (lp->tx_count == (KORINA_NUM_TDS - 2))
+                       netif_stop_queue(dev);
+               else {
+                       dev->stats.tx_dropped++;
+                       dev_kfree_skb_any(skb);
+                       spin_unlock_irqrestore(&lp->lock, flags);
+
+                       return NETDEV_TX_BUSY;
+               }
+       }
+
+       lp->tx_count++;
+
+       lp->tx_skb[lp->tx_chain_tail] = skb;
+
+       length = skb->len;
+       dma_cache_wback((u32)skb->data, skb->len);
+
+       /* Setup the transmit descriptor. */
+       dma_cache_inv((u32) td, sizeof(*td));
+       td->ca = CPHYSADDR(skb->data);
+       chain_prev = (lp->tx_chain_tail - 1) & KORINA_TDS_MASK;
+       chain_next = (lp->tx_chain_tail + 1) & KORINA_TDS_MASK;
+
+       if (readl(&(lp->tx_dma_regs->dmandptr)) == 0) {
+               if (lp->tx_chain_status == desc_empty) {
+                       /* Update tail */
+                       td->control = DMA_COUNT(length) |
+                                       DMA_DESC_COF | DMA_DESC_IOF;
+                       /* Move tail */
+                       lp->tx_chain_tail = chain_next;
+                       /* Write to NDPTR */
+                       writel(CPHYSADDR(&lp->td_ring[lp->tx_chain_head]),
+                                       &lp->tx_dma_regs->dmandptr);
+                       /* Move head to tail */
+                       lp->tx_chain_head = lp->tx_chain_tail;
+               } else {
+                       /* Update tail */
+                       td->control = DMA_COUNT(length) |
+                                       DMA_DESC_COF | DMA_DESC_IOF;
+                       /* Link to prev */
+                       lp->td_ring[chain_prev].control &=
+                                       ~DMA_DESC_COF;
+                       /* Link to prev */
+                       lp->td_ring[chain_prev].link =  CPHYSADDR(td);
+                       /* Move tail */
+                       lp->tx_chain_tail = chain_next;
+                       /* Write to NDPTR */
+                       writel(CPHYSADDR(&lp->td_ring[lp->tx_chain_head]),
+                                       &(lp->tx_dma_regs->dmandptr));
+                       /* Move head to tail */
+                       lp->tx_chain_head = lp->tx_chain_tail;
+                       lp->tx_chain_status = desc_empty;
+               }
+       } else {
+               if (lp->tx_chain_status == desc_empty) {
+                       /* Update tail */
+                       td->control = DMA_COUNT(length) |
+                                       DMA_DESC_COF | DMA_DESC_IOF;
+                       /* Move tail */
+                       lp->tx_chain_tail = chain_next;
+                       lp->tx_chain_status = desc_filled;
+               } else {
+                       /* Update tail */
+                       td->control = DMA_COUNT(length) |
+                                       DMA_DESC_COF | DMA_DESC_IOF;
+                       lp->td_ring[chain_prev].control &=
+                                       ~DMA_DESC_COF;
+                       lp->td_ring[chain_prev].link =  CPHYSADDR(td);
+                       lp->tx_chain_tail = chain_next;
+               }
+       }
+       dma_cache_wback((u32) td, sizeof(*td));
+
+       dev->trans_start = jiffies;
+       spin_unlock_irqrestore(&lp->lock, flags);
+
+       return NETDEV_TX_OK;
+}
+
+static int mdio_read(struct net_device *dev, int mii_id, int reg)
+{
+       struct korina_private *lp = netdev_priv(dev);
+       int ret;
+
+       mii_id = ((lp->rx_irq == 0x2c ? 1 : 0) << 8);
+
+       writel(0, &lp->eth_regs->miimcfg);
+       writel(0, &lp->eth_regs->miimcmd);
+       writel(mii_id | reg, &lp->eth_regs->miimaddr);
+       writel(ETH_MII_CMD_SCN, &lp->eth_regs->miimcmd);
+
+       ret = (int)(readl(&lp->eth_regs->miimrdd));
+       return ret;
+}
+
+static void mdio_write(struct net_device *dev, int mii_id, int reg, int val)
+{
+       struct korina_private *lp = netdev_priv(dev);
+
+       mii_id = ((lp->rx_irq == 0x2c ? 1 : 0) << 8);
+
+       writel(0, &lp->eth_regs->miimcfg);
+       writel(1, &lp->eth_regs->miimcmd);
+       writel(mii_id | reg, &lp->eth_regs->miimaddr);
+       writel(ETH_MII_CMD_SCN, &lp->eth_regs->miimcmd);
+       writel(val, &lp->eth_regs->miimwtd);
+}
+
+/* Ethernet Rx DMA interrupt */
+static irqreturn_t korina_rx_dma_interrupt(int irq, void *dev_id)
+{
+       struct net_device *dev = dev_id;
+       struct korina_private *lp = netdev_priv(dev);
+       u32 dmas, dmasm;
+       irqreturn_t retval;
+
+       dmas = readl(&lp->rx_dma_regs->dmas);
+       if (dmas & (DMA_STAT_DONE | DMA_STAT_HALT | DMA_STAT_ERR)) {
+               dmasm = readl(&lp->rx_dma_regs->dmasm);
+               writel(dmasm | (DMA_STAT_DONE |
+                               DMA_STAT_HALT | DMA_STAT_ERR),
+                               &lp->rx_dma_regs->dmasm);
+
+               napi_schedule(&lp->napi);
+
+               if (dmas & DMA_STAT_ERR)
+                       printk(KERN_ERR "%s: DMA error\n", dev->name);
+
+               retval = IRQ_HANDLED;
+       } else
+               retval = IRQ_NONE;
+
+       return retval;
+}
+
+static int korina_rx(struct net_device *dev, int limit)
+{
+       struct korina_private *lp = netdev_priv(dev);
+       struct dma_desc *rd = &lp->rd_ring[lp->rx_next_done];
+       struct sk_buff *skb, *skb_new;
+       u8 *pkt_buf;
+       u32 devcs, pkt_len, dmas;
+       int count;
+
+       dma_cache_inv((u32)rd, sizeof(*rd));
+
+       for (count = 0; count < limit; count++) {
+               skb = lp->rx_skb[lp->rx_next_done];
+               skb_new = NULL;
+
+               devcs = rd->devcs;
+
+               if ((KORINA_RBSIZE - (u32)DMA_COUNT(rd->control)) == 0)
+                       break;
+
+               /* Update statistics counters */
+               if (devcs & ETH_RX_CRC)
+                       dev->stats.rx_crc_errors++;
+               if (devcs & ETH_RX_LOR)
+                       dev->stats.rx_length_errors++;
+               if (devcs & ETH_RX_LE)
+                       dev->stats.rx_length_errors++;
+               if (devcs & ETH_RX_OVR)
+                       dev->stats.rx_fifo_errors++;
+               if (devcs & ETH_RX_CV)
+                       dev->stats.rx_frame_errors++;
+               if (devcs & ETH_RX_CES)
+                       dev->stats.rx_length_errors++;
+               if (devcs & ETH_RX_MP)
+                       dev->stats.multicast++;
+
+               if ((devcs & ETH_RX_LD) != ETH_RX_LD) {
+                       /* check that this is a whole packet
+                        * WARNING: DMA_FD bit incorrectly set
+                        * in Rc32434 (errata ref #077) */
+                       dev->stats.rx_errors++;
+                       dev->stats.rx_dropped++;
+               } else if ((devcs & ETH_RX_ROK)) {
+                       pkt_len = RCVPKT_LENGTH(devcs);
+
+                       /* must be the (first and) last
+                        * descriptor then */
+                       pkt_buf = (u8 *)lp->rx_skb[lp->rx_next_done]->data;
+
+                       /* invalidate the cache */
+                       dma_cache_inv((unsigned long)pkt_buf, pkt_len - 4);
+
+                       /* Malloc up new buffer. */
+                       skb_new = netdev_alloc_skb_ip_align(dev, KORINA_RBSIZE);
+
+                       if (!skb_new)
+                               break;
+                       /* Do not count the CRC */
+                       skb_put(skb, pkt_len - 4);
+                       skb->protocol = eth_type_trans(skb, dev);
+
+                       /* Pass the packet to upper layers */
+                       netif_receive_skb(skb);
+                       dev->stats.rx_packets++;
+                       dev->stats.rx_bytes += pkt_len;
+
+                       /* Update the mcast stats */
+                       if (devcs & ETH_RX_MP)
+                               dev->stats.multicast++;
+
+                       lp->rx_skb[lp->rx_next_done] = skb_new;
+               }
+
+               rd->devcs = 0;
+
+               /* Restore descriptor's curr_addr */
+               if (skb_new)
+                       rd->ca = CPHYSADDR(skb_new->data);
+               else
+                       rd->ca = CPHYSADDR(skb->data);
+
+               rd->control = DMA_COUNT(KORINA_RBSIZE) |
+                       DMA_DESC_COD | DMA_DESC_IOD;
+               lp->rd_ring[(lp->rx_next_done - 1) &
+                       KORINA_RDS_MASK].control &=
+                       ~DMA_DESC_COD;
+
+               lp->rx_next_done = (lp->rx_next_done + 1) & KORINA_RDS_MASK;
+               dma_cache_wback((u32)rd, sizeof(*rd));
+               rd = &lp->rd_ring[lp->rx_next_done];
+               writel(~DMA_STAT_DONE, &lp->rx_dma_regs->dmas);
+       }
+
+       dmas = readl(&lp->rx_dma_regs->dmas);
+
+       if (dmas & DMA_STAT_HALT) {
+               writel(~(DMA_STAT_HALT | DMA_STAT_ERR),
+                               &lp->rx_dma_regs->dmas);
+
+               lp->dma_halt_cnt++;
+               rd->devcs = 0;
+               skb = lp->rx_skb[lp->rx_next_done];
+               rd->ca = CPHYSADDR(skb->data);
+               dma_cache_wback((u32)rd, sizeof(*rd));
+               korina_chain_rx(lp, rd);
+       }
+
+       return count;
+}
+
+static int korina_poll(struct napi_struct *napi, int budget)
+{
+       struct korina_private *lp =
+               container_of(napi, struct korina_private, napi);
+       struct net_device *dev = lp->dev;
+       int work_done;
+
+       work_done = korina_rx(dev, budget);
+       if (work_done < budget) {
+               napi_complete(napi);
+
+               writel(readl(&lp->rx_dma_regs->dmasm) &
+                       ~(DMA_STAT_DONE | DMA_STAT_HALT | DMA_STAT_ERR),
+                       &lp->rx_dma_regs->dmasm);
+       }
+       return work_done;
+}
+
+/*
+ * Set or clear the multicast filter for this adaptor.
+ */
+static void korina_multicast_list(struct net_device *dev)
+{
+       struct korina_private *lp = netdev_priv(dev);
+       unsigned long flags;
+       struct netdev_hw_addr *ha;
+       u32 recognise = ETH_ARC_AB;     /* always accept broadcasts */
+
+       /* Set promiscuous mode */
+       if (dev->flags & IFF_PROMISC)
+               recognise |= ETH_ARC_PRO;
+
+       else if ((dev->flags & IFF_ALLMULTI) || (netdev_mc_count(dev) > 4))
+               /* All multicast and broadcast */
+               recognise |= ETH_ARC_AM;
+
+       /* Build the hash table */
+       if (netdev_mc_count(dev) > 4) {
+               u16 hash_table[4] = { 0 };
+               u32 crc;
+
+               netdev_for_each_mc_addr(ha, dev) {
+                       crc = ether_crc_le(6, ha->addr);
+                       crc >>= 26;
+                       hash_table[crc >> 4] |= 1 << (15 - (crc & 0xf));
+               }
+               /* Accept filtered multicast */
+               recognise |= ETH_ARC_AFM;
+
+               /* Fill the MAC hash tables with their values */
+               writel((u32)(hash_table[1] << 16 | hash_table[0]),
+                                       &lp->eth_regs->ethhash0);
+               writel((u32)(hash_table[3] << 16 | hash_table[2]),
+                                       &lp->eth_regs->ethhash1);
+       }
+
+       spin_lock_irqsave(&lp->lock, flags);
+       writel(recognise, &lp->eth_regs->etharc);
+       spin_unlock_irqrestore(&lp->lock, flags);
+}
+
+static void korina_tx(struct net_device *dev)
+{
+       struct korina_private *lp = netdev_priv(dev);
+       struct dma_desc *td = &lp->td_ring[lp->tx_next_done];
+       u32 devcs;
+       u32 dmas;
+
+       spin_lock(&lp->lock);
+
+       /* Process all desc that are done */
+       while (IS_DMA_FINISHED(td->control)) {
+               if (lp->tx_full == 1) {
+                       netif_wake_queue(dev);
+                       lp->tx_full = 0;
+               }
+
+               devcs = lp->td_ring[lp->tx_next_done].devcs;
+               if ((devcs & (ETH_TX_FD | ETH_TX_LD)) !=
+                               (ETH_TX_FD | ETH_TX_LD)) {
+                       dev->stats.tx_errors++;
+                       dev->stats.tx_dropped++;
+
+                       /* Should never happen */
+                       printk(KERN_ERR "%s: split tx ignored\n",
+                                                       dev->name);
+               } else if (devcs & ETH_TX_TOK) {
+                       dev->stats.tx_packets++;
+                       dev->stats.tx_bytes +=
+                                       lp->tx_skb[lp->tx_next_done]->len;
+               } else {
+                       dev->stats.tx_errors++;
+                       dev->stats.tx_dropped++;
+
+                       /* Underflow */
+                       if (devcs & ETH_TX_UND)
+                               dev->stats.tx_fifo_errors++;
+
+                       /* Oversized frame */
+                       if (devcs & ETH_TX_OF)
+                               dev->stats.tx_aborted_errors++;
+
+                       /* Excessive deferrals */
+                       if (devcs & ETH_TX_ED)
+                               dev->stats.tx_carrier_errors++;
+
+                       /* Collisions: medium busy */
+                       if (devcs & ETH_TX_EC)
+                               dev->stats.collisions++;
+
+                       /* Late collision */
+                       if (devcs & ETH_TX_LC)
+                               dev->stats.tx_window_errors++;
+               }
+
+               /* We must always free the original skb */
+               if (lp->tx_skb[lp->tx_next_done]) {
+                       dev_kfree_skb_any(lp->tx_skb[lp->tx_next_done]);
+                       lp->tx_skb[lp->tx_next_done] = NULL;
+               }
+
+               lp->td_ring[lp->tx_next_done].control = DMA_DESC_IOF;
+               lp->td_ring[lp->tx_next_done].devcs = ETH_TX_FD | ETH_TX_LD;
+               lp->td_ring[lp->tx_next_done].link = 0;
+               lp->td_ring[lp->tx_next_done].ca = 0;
+               lp->tx_count--;
+
+               /* Go on to next transmission */
+               lp->tx_next_done = (lp->tx_next_done + 1) & KORINA_TDS_MASK;
+               td = &lp->td_ring[lp->tx_next_done];
+
+       }
+
+       /* Clear the DMA status register */
+       dmas = readl(&lp->tx_dma_regs->dmas);
+       writel(~dmas, &lp->tx_dma_regs->dmas);
+
+       writel(readl(&lp->tx_dma_regs->dmasm) &
+                       ~(DMA_STAT_FINI | DMA_STAT_ERR),
+                       &lp->tx_dma_regs->dmasm);
+
+       spin_unlock(&lp->lock);
+}
+
+static irqreturn_t
+korina_tx_dma_interrupt(int irq, void *dev_id)
+{
+       struct net_device *dev = dev_id;
+       struct korina_private *lp = netdev_priv(dev);
+       u32 dmas, dmasm;
+       irqreturn_t retval;
+
+       dmas = readl(&lp->tx_dma_regs->dmas);
+
+       if (dmas & (DMA_STAT_FINI | DMA_STAT_ERR)) {
+               dmasm = readl(&lp->tx_dma_regs->dmasm);
+               writel(dmasm | (DMA_STAT_FINI | DMA_STAT_ERR),
+                               &lp->tx_dma_regs->dmasm);
+
+               korina_tx(dev);
+
+               if (lp->tx_chain_status == desc_filled &&
+                       (readl(&(lp->tx_dma_regs->dmandptr)) == 0)) {
+                       writel(CPHYSADDR(&lp->td_ring[lp->tx_chain_head]),
+                               &(lp->tx_dma_regs->dmandptr));
+                       lp->tx_chain_status = desc_empty;
+                       lp->tx_chain_head = lp->tx_chain_tail;
+                       dev->trans_start = jiffies;
+               }
+               if (dmas & DMA_STAT_ERR)
+                       printk(KERN_ERR "%s: DMA error\n", dev->name);
+
+               retval = IRQ_HANDLED;
+       } else
+               retval = IRQ_NONE;
+
+       return retval;
+}
+
+
+static void korina_check_media(struct net_device *dev, unsigned int init_media)
+{
+       struct korina_private *lp = netdev_priv(dev);
+
+       mii_check_media(&lp->mii_if, 0, init_media);
+
+       if (lp->mii_if.full_duplex)
+               writel(readl(&lp->eth_regs->ethmac2) | ETH_MAC2_FD,
+                                               &lp->eth_regs->ethmac2);
+       else
+               writel(readl(&lp->eth_regs->ethmac2) & ~ETH_MAC2_FD,
+                                               &lp->eth_regs->ethmac2);
+}
+
+static void korina_poll_media(unsigned long data)
+{
+       struct net_device *dev = (struct net_device *) data;
+       struct korina_private *lp = netdev_priv(dev);
+
+       korina_check_media(dev, 0);
+       mod_timer(&lp->media_check_timer, jiffies + HZ);
+}
+
+static void korina_set_carrier(struct mii_if_info *mii)
+{
+       if (mii->force_media) {
+               /* autoneg is off: Link is always assumed to be up */
+               if (!netif_carrier_ok(mii->dev))
+                       netif_carrier_on(mii->dev);
+       } else  /* Let MMI library update carrier status */
+               korina_check_media(mii->dev, 0);
+}
+
+static int korina_ioctl(struct net_device *dev, struct ifreq *rq, int cmd)
+{
+       struct korina_private *lp = netdev_priv(dev);
+       struct mii_ioctl_data *data = if_mii(rq);
+       int rc;
+
+       if (!netif_running(dev))
+               return -EINVAL;
+       spin_lock_irq(&lp->lock);
+       rc = generic_mii_ioctl(&lp->mii_if, data, cmd, NULL);
+       spin_unlock_irq(&lp->lock);
+       korina_set_carrier(&lp->mii_if);
+
+       return rc;
+}
+
+/* ethtool helpers */
+static void netdev_get_drvinfo(struct net_device *dev,
+                       struct ethtool_drvinfo *info)
+{
+       struct korina_private *lp = netdev_priv(dev);
+
+       strlcpy(info->driver, DRV_NAME, sizeof(info->driver));
+       strlcpy(info->version, DRV_VERSION, sizeof(info->version));
+       strlcpy(info->bus_info, lp->dev->name, sizeof(info->bus_info));
+}
+
+static int netdev_get_settings(struct net_device *dev, struct ethtool_cmd *cmd)
+{
+       struct korina_private *lp = netdev_priv(dev);
+       int rc;
+
+       spin_lock_irq(&lp->lock);
+       rc = mii_ethtool_gset(&lp->mii_if, cmd);
+       spin_unlock_irq(&lp->lock);
+
+       return rc;
+}
+
+static int netdev_set_settings(struct net_device *dev, struct ethtool_cmd *cmd)
+{
+       struct korina_private *lp = netdev_priv(dev);
+       int rc;
+
+       spin_lock_irq(&lp->lock);
+       rc = mii_ethtool_sset(&lp->mii_if, cmd);
+       spin_unlock_irq(&lp->lock);
+       korina_set_carrier(&lp->mii_if);
+
+       return rc;
+}
+
+static u32 netdev_get_link(struct net_device *dev)
+{
+       struct korina_private *lp = netdev_priv(dev);
+
+       return mii_link_ok(&lp->mii_if);
+}
+
+static const struct ethtool_ops netdev_ethtool_ops = {
+       .get_drvinfo            = netdev_get_drvinfo,
+       .get_settings           = netdev_get_settings,
+       .set_settings           = netdev_set_settings,
+       .get_link               = netdev_get_link,
+};
+
+static int korina_alloc_ring(struct net_device *dev)
+{
+       struct korina_private *lp = netdev_priv(dev);
+       struct sk_buff *skb;
+       int i;
+
+       /* Initialize the transmit descriptors */
+       for (i = 0; i < KORINA_NUM_TDS; i++) {
+               lp->td_ring[i].control = DMA_DESC_IOF;
+               lp->td_ring[i].devcs = ETH_TX_FD | ETH_TX_LD;
+               lp->td_ring[i].ca = 0;
+               lp->td_ring[i].link = 0;
+       }
+       lp->tx_next_done = lp->tx_chain_head = lp->tx_chain_tail =
+                       lp->tx_full = lp->tx_count = 0;
+       lp->tx_chain_status = desc_empty;
+
+       /* Initialize the receive descriptors */
+       for (i = 0; i < KORINA_NUM_RDS; i++) {
+               skb = netdev_alloc_skb_ip_align(dev, KORINA_RBSIZE);
+               if (!skb)
+                       return -ENOMEM;
+               lp->rx_skb[i] = skb;
+               lp->rd_ring[i].control = DMA_DESC_IOD |
+                               DMA_COUNT(KORINA_RBSIZE);
+               lp->rd_ring[i].devcs = 0;
+               lp->rd_ring[i].ca = CPHYSADDR(skb->data);
+               lp->rd_ring[i].link = CPHYSADDR(&lp->rd_ring[i+1]);
+       }
+
+       /* loop back receive descriptors, so the last
+        * descriptor points to the first one */
+       lp->rd_ring[i - 1].link = CPHYSADDR(&lp->rd_ring[0]);
+       lp->rd_ring[i - 1].control |= DMA_DESC_COD;
+
+       lp->rx_next_done  = 0;
+       lp->rx_chain_head = 0;
+       lp->rx_chain_tail = 0;
+       lp->rx_chain_status = desc_empty;
+
+       return 0;
+}
+
+static void korina_free_ring(struct net_device *dev)
+{
+       struct korina_private *lp = netdev_priv(dev);
+       int i;
+
+       for (i = 0; i < KORINA_NUM_RDS; i++) {
+               lp->rd_ring[i].control = 0;
+               if (lp->rx_skb[i])
+                       dev_kfree_skb_any(lp->rx_skb[i]);
+               lp->rx_skb[i] = NULL;
+       }
+
+       for (i = 0; i < KORINA_NUM_TDS; i++) {
+               lp->td_ring[i].control = 0;
+               if (lp->tx_skb[i])
+                       dev_kfree_skb_any(lp->tx_skb[i]);
+               lp->tx_skb[i] = NULL;
+       }
+}
+
+/*
+ * Initialize the RC32434 ethernet controller.
+ */
+static int korina_init(struct net_device *dev)
+{
+       struct korina_private *lp = netdev_priv(dev);
+
+       /* Disable DMA */
+       korina_abort_tx(dev);
+       korina_abort_rx(dev);
+
+       /* reset ethernet logic */
+       writel(0, &lp->eth_regs->ethintfc);
+       while ((readl(&lp->eth_regs->ethintfc) & ETH_INT_FC_RIP))
+               dev->trans_start = jiffies;
+
+       /* Enable Ethernet Interface */
+       writel(ETH_INT_FC_EN, &lp->eth_regs->ethintfc);
+
+       /* Allocate rings */
+       if (korina_alloc_ring(dev)) {
+               printk(KERN_ERR "%s: descriptor allocation failed\n", dev->name);
+               korina_free_ring(dev);
+               return -ENOMEM;
+       }
+
+       writel(0, &lp->rx_dma_regs->dmas);
+       /* Start Rx DMA */
+       korina_start_rx(lp, &lp->rd_ring[0]);
+
+       writel(readl(&lp->tx_dma_regs->dmasm) &
+                       ~(DMA_STAT_FINI | DMA_STAT_ERR),
+                       &lp->tx_dma_regs->dmasm);
+       writel(readl(&lp->rx_dma_regs->dmasm) &
+                       ~(DMA_STAT_DONE | DMA_STAT_HALT | DMA_STAT_ERR),
+                       &lp->rx_dma_regs->dmasm);
+
+       /* Accept only packets destined for this Ethernet device address */
+       writel(ETH_ARC_AB, &lp->eth_regs->etharc);
+
+       /* Set all Ether station address registers to their initial values */
+       writel(STATION_ADDRESS_LOW(dev), &lp->eth_regs->ethsal0);
+       writel(STATION_ADDRESS_HIGH(dev), &lp->eth_regs->ethsah0);
+
+       writel(STATION_ADDRESS_LOW(dev), &lp->eth_regs->ethsal1);
+       writel(STATION_ADDRESS_HIGH(dev), &lp->eth_regs->ethsah1);
+
+       writel(STATION_ADDRESS_LOW(dev), &lp->eth_regs->ethsal2);
+       writel(STATION_ADDRESS_HIGH(dev), &lp->eth_regs->ethsah2);
+
+       writel(STATION_ADDRESS_LOW(dev), &lp->eth_regs->ethsal3);
+       writel(STATION_ADDRESS_HIGH(dev), &lp->eth_regs->ethsah3);
+
+
+       /* Frame Length Checking, Pad Enable, CRC Enable, Full Duplex set */
+       writel(ETH_MAC2_PE | ETH_MAC2_CEN | ETH_MAC2_FD,
+                       &lp->eth_regs->ethmac2);
+
+       /* Back to back inter-packet-gap */
+       writel(0x15, &lp->eth_regs->ethipgt);
+       /* Non - Back to back inter-packet-gap */
+       writel(0x12, &lp->eth_regs->ethipgr);
+
+       /* Management Clock Prescaler Divisor
+        * Clock independent setting */
+       writel(((idt_cpu_freq) / MII_CLOCK + 1) & ~1,
+                      &lp->eth_regs->ethmcp);
+
+       /* don't transmit until fifo contains 48b */
+       writel(48, &lp->eth_regs->ethfifott);
+
+       writel(ETH_MAC1_RE, &lp->eth_regs->ethmac1);
+
+       napi_enable(&lp->napi);
+       netif_start_queue(dev);
+
+       return 0;
+}
+
+/*
+ * Restart the RC32434 ethernet controller.
+ */
+static void korina_restart_task(struct work_struct *work)
+{
+       struct korina_private *lp = container_of(work,
+                       struct korina_private, restart_task);
+       struct net_device *dev = lp->dev;
+
+       /*
+        * Disable interrupts
+        */
+       disable_irq(lp->rx_irq);
+       disable_irq(lp->tx_irq);
+       disable_irq(lp->ovr_irq);
+       disable_irq(lp->und_irq);
+
+       writel(readl(&lp->tx_dma_regs->dmasm) |
+                               DMA_STAT_FINI | DMA_STAT_ERR,
+                               &lp->tx_dma_regs->dmasm);
+       writel(readl(&lp->rx_dma_regs->dmasm) |
+                               DMA_STAT_DONE | DMA_STAT_HALT | DMA_STAT_ERR,
+                               &lp->rx_dma_regs->dmasm);
+
+       korina_free_ring(dev);
+
+       napi_disable(&lp->napi);
+
+       if (korina_init(dev) < 0) {
+               printk(KERN_ERR "%s: cannot restart device\n", dev->name);
+               return;
+       }
+       korina_multicast_list(dev);
+
+       enable_irq(lp->und_irq);
+       enable_irq(lp->ovr_irq);
+       enable_irq(lp->tx_irq);
+       enable_irq(lp->rx_irq);
+}
+
+static void korina_clear_and_restart(struct net_device *dev, u32 value)
+{
+       struct korina_private *lp = netdev_priv(dev);
+
+       netif_stop_queue(dev);
+       writel(value, &lp->eth_regs->ethintfc);
+       schedule_work(&lp->restart_task);
+}
+
+/* Ethernet Tx Underflow interrupt */
+static irqreturn_t korina_und_interrupt(int irq, void *dev_id)
+{
+       struct net_device *dev = dev_id;
+       struct korina_private *lp = netdev_priv(dev);
+       unsigned int und;
+
+       spin_lock(&lp->lock);
+
+       und = readl(&lp->eth_regs->ethintfc);
+
+       if (und & ETH_INT_FC_UND)
+               korina_clear_and_restart(dev, und & ~ETH_INT_FC_UND);
+
+       spin_unlock(&lp->lock);
+
+       return IRQ_HANDLED;
+}
+
+static void korina_tx_timeout(struct net_device *dev)
+{
+       struct korina_private *lp = netdev_priv(dev);
+
+       schedule_work(&lp->restart_task);
+}
+
+/* Ethernet Rx Overflow interrupt */
+static irqreturn_t
+korina_ovr_interrupt(int irq, void *dev_id)
+{
+       struct net_device *dev = dev_id;
+       struct korina_private *lp = netdev_priv(dev);
+       unsigned int ovr;
+
+       spin_lock(&lp->lock);
+       ovr = readl(&lp->eth_regs->ethintfc);
+
+       if (ovr & ETH_INT_FC_OVR)
+               korina_clear_and_restart(dev, ovr & ~ETH_INT_FC_OVR);
+
+       spin_unlock(&lp->lock);
+
+       return IRQ_HANDLED;
+}
+
+#ifdef CONFIG_NET_POLL_CONTROLLER
+static void korina_poll_controller(struct net_device *dev)
+{
+       disable_irq(dev->irq);
+       korina_tx_dma_interrupt(dev->irq, dev);
+       enable_irq(dev->irq);
+}
+#endif
+
+static int korina_open(struct net_device *dev)
+{
+       struct korina_private *lp = netdev_priv(dev);
+       int ret;
+
+       /* Initialize */
+       ret = korina_init(dev);
+       if (ret < 0) {
+               printk(KERN_ERR "%s: cannot open device\n", dev->name);
+               goto out;
+       }
+
+       /* Install the interrupt handler
+        * that handles the Done Finished
+        * Ovr and Und Events */
+       ret = request_irq(lp->rx_irq, korina_rx_dma_interrupt,
+                       0, "Korina ethernet Rx", dev);
+       if (ret < 0) {
+               printk(KERN_ERR "%s: unable to get Rx DMA IRQ %d\n",
+                   dev->name, lp->rx_irq);
+               goto err_release;
+       }
+       ret = request_irq(lp->tx_irq, korina_tx_dma_interrupt,
+                       0, "Korina ethernet Tx", dev);
+       if (ret < 0) {
+               printk(KERN_ERR "%s: unable to get Tx DMA IRQ %d\n",
+                   dev->name, lp->tx_irq);
+               goto err_free_rx_irq;
+       }
+
+       /* Install handler for overrun error. */
+       ret = request_irq(lp->ovr_irq, korina_ovr_interrupt,
+                       0, "Ethernet Overflow", dev);
+       if (ret < 0) {
+               printk(KERN_ERR "%s: unable to get OVR IRQ %d\n",
+                   dev->name, lp->ovr_irq);
+               goto err_free_tx_irq;
+       }
+
+       /* Install handler for underflow error. */
+       ret = request_irq(lp->und_irq, korina_und_interrupt,
+                       0, "Ethernet Underflow", dev);
+       if (ret < 0) {
+               printk(KERN_ERR "%s: unable to get UND IRQ %d\n",
+                   dev->name, lp->und_irq);
+               goto err_free_ovr_irq;
+       }
+       mod_timer(&lp->media_check_timer, jiffies + 1);
+out:
+       return ret;
+
+err_free_ovr_irq:
+       free_irq(lp->ovr_irq, dev);
+err_free_tx_irq:
+       free_irq(lp->tx_irq, dev);
+err_free_rx_irq:
+       free_irq(lp->rx_irq, dev);
+err_release:
+       korina_free_ring(dev);
+       goto out;
+}
+
+static int korina_close(struct net_device *dev)
+{
+       struct korina_private *lp = netdev_priv(dev);
+       u32 tmp;
+
+       del_timer(&lp->media_check_timer);
+
+       /* Disable interrupts */
+       disable_irq(lp->rx_irq);
+       disable_irq(lp->tx_irq);
+       disable_irq(lp->ovr_irq);
+       disable_irq(lp->und_irq);
+
+       korina_abort_tx(dev);
+       tmp = readl(&lp->tx_dma_regs->dmasm);
+       tmp = tmp | DMA_STAT_FINI | DMA_STAT_ERR;
+       writel(tmp, &lp->tx_dma_regs->dmasm);
+
+       korina_abort_rx(dev);
+       tmp = readl(&lp->rx_dma_regs->dmasm);
+       tmp = tmp | DMA_STAT_DONE | DMA_STAT_HALT | DMA_STAT_ERR;
+       writel(tmp, &lp->rx_dma_regs->dmasm);
+
+       korina_free_ring(dev);
+
+       napi_disable(&lp->napi);
+
+       cancel_work_sync(&lp->restart_task);
+
+       free_irq(lp->rx_irq, dev);
+       free_irq(lp->tx_irq, dev);
+       free_irq(lp->ovr_irq, dev);
+       free_irq(lp->und_irq, dev);
+
+       return 0;
+}
+
+static const struct net_device_ops korina_netdev_ops = {
+       .ndo_open               = korina_open,
+       .ndo_stop               = korina_close,
+       .ndo_start_xmit         = korina_send_packet,
+       .ndo_set_rx_mode        = korina_multicast_list,
+       .ndo_tx_timeout         = korina_tx_timeout,
+       .ndo_do_ioctl           = korina_ioctl,
+       .ndo_change_mtu         = eth_change_mtu,
+       .ndo_validate_addr      = eth_validate_addr,
+       .ndo_set_mac_address    = eth_mac_addr,
+#ifdef CONFIG_NET_POLL_CONTROLLER
+       .ndo_poll_controller    = korina_poll_controller,
+#endif
+};
+
+static int korina_probe(struct platform_device *pdev)
+{
+       struct korina_device *bif = platform_get_drvdata(pdev);
+       struct korina_private *lp;
+       struct net_device *dev;
+       struct resource *r;
+       int rc;
+
+       dev = alloc_etherdev(sizeof(struct korina_private));
+       if (!dev)
+               return -ENOMEM;
+
+       SET_NETDEV_DEV(dev, &pdev->dev);
+       lp = netdev_priv(dev);
+
+       bif->dev = dev;
+       memcpy(dev->dev_addr, bif->mac, ETH_ALEN);
+
+       lp->rx_irq = platform_get_irq_byname(pdev, "korina_rx");
+       lp->tx_irq = platform_get_irq_byname(pdev, "korina_tx");
+       lp->ovr_irq = platform_get_irq_byname(pdev, "korina_ovr");
+       lp->und_irq = platform_get_irq_byname(pdev, "korina_und");
+
+       r = platform_get_resource_byname(pdev, IORESOURCE_MEM, "korina_regs");
+       dev->base_addr = r->start;
+       lp->eth_regs = ioremap_nocache(r->start, resource_size(r));
+       if (!lp->eth_regs) {
+               printk(KERN_ERR DRV_NAME ": cannot remap registers\n");
+               rc = -ENXIO;
+               goto probe_err_out;
+       }
+
+       r = platform_get_resource_byname(pdev, IORESOURCE_MEM, "korina_dma_rx");
+       lp->rx_dma_regs = ioremap_nocache(r->start, resource_size(r));
+       if (!lp->rx_dma_regs) {
+               printk(KERN_ERR DRV_NAME ": cannot remap Rx DMA registers\n");
+               rc = -ENXIO;
+               goto probe_err_dma_rx;
+       }
+
+       r = platform_get_resource_byname(pdev, IORESOURCE_MEM, "korina_dma_tx");
+       lp->tx_dma_regs = ioremap_nocache(r->start, resource_size(r));
+       if (!lp->tx_dma_regs) {
+               printk(KERN_ERR DRV_NAME ": cannot remap Tx DMA registers\n");
+               rc = -ENXIO;
+               goto probe_err_dma_tx;
+       }
+
+       lp->td_ring = kmalloc(TD_RING_SIZE + RD_RING_SIZE, GFP_KERNEL);
+       if (!lp->td_ring) {
+               rc = -ENXIO;
+               goto probe_err_td_ring;
+       }
+
+       dma_cache_inv((unsigned long)(lp->td_ring),
+                       TD_RING_SIZE + RD_RING_SIZE);
+
+       /* now convert TD_RING pointer to KSEG1 */
+       lp->td_ring = (struct dma_desc *)KSEG1ADDR(lp->td_ring);
+       lp->rd_ring = &lp->td_ring[KORINA_NUM_TDS];
+
+       spin_lock_init(&lp->lock);
+       /* just use the rx dma irq */
+       dev->irq = lp->rx_irq;
+       lp->dev = dev;
+
+       dev->netdev_ops = &korina_netdev_ops;
+       dev->ethtool_ops = &netdev_ethtool_ops;
+       dev->watchdog_timeo = TX_TIMEOUT;
+       netif_napi_add(dev, &lp->napi, korina_poll, 64);
+
+       lp->phy_addr = (((lp->rx_irq == 0x2c? 1:0) << 8) | 0x05);
+       lp->mii_if.dev = dev;
+       lp->mii_if.mdio_read = mdio_read;
+       lp->mii_if.mdio_write = mdio_write;
+       lp->mii_if.phy_id = lp->phy_addr;
+       lp->mii_if.phy_id_mask = 0x1f;
+       lp->mii_if.reg_num_mask = 0x1f;
+
+       rc = register_netdev(dev);
+       if (rc < 0) {
+               printk(KERN_ERR DRV_NAME
+                       ": cannot register net device: %d\n", rc);
+               goto probe_err_register;
+       }
+       setup_timer(&lp->media_check_timer, korina_poll_media, (unsigned long) dev);
+
+       INIT_WORK(&lp->restart_task, korina_restart_task);
+
+       printk(KERN_INFO "%s: " DRV_NAME "-" DRV_VERSION " " DRV_RELDATE "\n",
+                       dev->name);
+out:
+       return rc;
+
+probe_err_register:
+       kfree(lp->td_ring);
+probe_err_td_ring:
+       iounmap(lp->tx_dma_regs);
+probe_err_dma_tx:
+       iounmap(lp->rx_dma_regs);
+probe_err_dma_rx:
+       iounmap(lp->eth_regs);
+probe_err_out:
+       free_netdev(dev);
+       goto out;
+}
+
+static int korina_remove(struct platform_device *pdev)
+{
+       struct korina_device *bif = platform_get_drvdata(pdev);
+       struct korina_private *lp = netdev_priv(bif->dev);
+
+       iounmap(lp->eth_regs);
+       iounmap(lp->rx_dma_regs);
+       iounmap(lp->tx_dma_regs);
+
+       unregister_netdev(bif->dev);
+       free_netdev(bif->dev);
+
+       return 0;
+}
+
+static struct platform_driver korina_driver = {
+       .driver.name = "korina",
+       .probe = korina_probe,
+       .remove = korina_remove,
+};
+
+module_platform_driver(korina_driver);
+
+MODULE_AUTHOR("Philip Rischel <rischelp@idt.com>");
+MODULE_AUTHOR("Felix Fietkau <nbd@openwrt.org>");
+MODULE_AUTHOR("Florian Fainelli <florian@openwrt.org>");
+MODULE_DESCRIPTION("IDT RC32434 (Korina) Ethernet driver");
+MODULE_LICENSE("GPL");