/* * This file is subject to the terms and conditions of the GNU General Public * License. See the file "COPYING" in the main directory of this archive * for more details. */ #include <linux/init.h> #include <linux/io.h> #include <linux/kernel.h> #include <linux/module.h> #include <linux/netdevice.h> #include <linux/etherdevice.h> #include <linux/platform_device.h> #include <asm/mips-boards/simint.h> #define MIPSNET_VERSION "2007-11-17" /* * Net status/control block as seen by sw in the core. */ struct mipsnet_regs { /* * Device info for probing, reads as MIPSNET%d where %d is some * form of version. */ u64 devId; /*0x00 */ /* * read only busy flag. * Set and cleared by the Net Device to indicate that an rx or a tx * is in progress. */ u32 busy; /*0x08 */ /* * Set by the Net Device. * The device will set it once data has been received. * The value is the number of bytes that should be read from * rxDataBuffer. The value will decrease till 0 until all the data * from rxDataBuffer has been read. */ u32 rxDataCount; /*0x0c */ #define MIPSNET_MAX_RXTX_DATACOUNT (1 << 16) /* * Settable from the MIPS core, cleared by the Net Device. * The core should set the number of bytes it wants to send, * then it should write those bytes of data to txDataBuffer. * The device will clear txDataCount has been processed (not * necessarily sent). */ u32 txDataCount; /*0x10 */ /* * Interrupt control * * Used to clear the interrupted generated by this dev. * Write a 1 to clear the interrupt. (except bit31). * * Bit0 is set if it was a tx-done interrupt. * Bit1 is set when new rx-data is available. * Until this bit is cleared there will be no other RXs. * * Bit31 is used for testing, it clears after a read. * Writing 1 to this bit will cause an interrupt to be generated. * To clear the test interrupt, write 0 to this register. */ u32 interruptControl; /*0x14 */ #define MIPSNET_INTCTL_TXDONE (1u << 0) #define MIPSNET_INTCTL_RXDONE (1u << 1) #define MIPSNET_INTCTL_TESTBIT (1u << 31) /* * Readonly core-specific interrupt info for the device to signal * the core. The meaning of the contents of this field might change. */ /* XXX: the whole memIntf interrupt scheme is messy: the device * should have no control what so ever of what VPE/register set is * being used. * The MemIntf should only expose interrupt lines, and something in * the config should be responsible for the line<->core/vpe bindings. */ u32 interruptInfo; /*0x18 */ /* * This is where the received data is read out. * There is more data to read until rxDataReady is 0. * Only 1 byte at this regs offset is used. */ u32 rxDataBuffer; /*0x1c */ /* * This is where the data to transmit is written. * Data should be written for the amount specified in the * txDataCount register. * Only 1 byte at this regs offset is used. */ u32 txDataBuffer; /*0x20 */ }; #define regaddr(dev, field) \ (dev->base_addr + offsetof(struct mipsnet_regs, field)) static char mipsnet_string[] = "mipsnet"; /* * Copy data from the MIPSNET rx data port */ static int ioiocpy_frommipsnet(struct net_device *dev, unsigned char *kdata, int len) { for (; len > 0; len--, kdata++) *kdata = inb(regaddr(dev, rxDataBuffer)); return inl(regaddr(dev, rxDataCount)); } static inline void mipsnet_put_todevice(struct net_device *dev, struct sk_buff *skb) { int count_to_go = skb->len; char *buf_ptr = skb->data; outl(skb->len, regaddr(dev, txDataCount)); for (; count_to_go; buf_ptr++, count_to_go--) outb(*buf_ptr, regaddr(dev, txDataBuffer)); dev->stats.tx_packets++; dev->stats.tx_bytes += skb->len; dev_kfree_skb(skb); } static int mipsnet_xmit(struct sk_buff *skb, struct net_device *dev) { /* * Only one packet at a time. Once TXDONE interrupt is serviced, the * queue will be restarted. */ netif_stop_queue(dev); mipsnet_put_todevice(dev, skb); return 0; } static inline ssize_t mipsnet_get_fromdev(struct net_device *dev, size_t len) { struct sk_buff *skb; if (!len) return len; skb = dev_alloc_skb(len + NET_IP_ALIGN); if (!skb) { dev->stats.rx_dropped++; return -ENOMEM; } skb_reserve(skb, NET_IP_ALIGN); if (ioiocpy_frommipsnet(dev, skb_put(skb, len), len)) return -EFAULT; skb->protocol = eth_type_trans(skb, dev); skb->ip_summed = CHECKSUM_UNNECESSARY; netif_rx(skb); dev->stats.rx_packets++; dev->stats.rx_bytes += len; return len; } static irqreturn_t mipsnet_interrupt(int irq, void *dev_id) { struct net_device *dev = dev_id; u32 int_flags; irqreturn_t ret = IRQ_NONE; if (irq != dev->irq) goto out_badirq; /* TESTBIT is cleared on read. */ int_flags = inl(regaddr(dev, interruptControl)); if (int_flags & MIPSNET_INTCTL_TESTBIT) { /* TESTBIT takes effect after a write with 0. */ outl(0, regaddr(dev, interruptControl)); ret = IRQ_HANDLED; } else if (int_flags & MIPSNET_INTCTL_TXDONE) { /* Only one packet at a time, we are done. */ dev->stats.tx_packets++; netif_wake_queue(dev); outl(MIPSNET_INTCTL_TXDONE, regaddr(dev, interruptControl)); ret = IRQ_HANDLED; } else if (int_flags & MIPSNET_INTCTL_RXDONE) { mipsnet_get_fromdev(dev, inl(regaddr(dev, rxDataCount))); outl(MIPSNET_INTCTL_RXDONE, regaddr(dev, interruptControl)); ret = IRQ_HANDLED; } return ret; out_badirq: printk(KERN_INFO "%s: %s(): irq %d for unknown device\n", dev->name, __FUNCTION__, irq); return ret; } static int mipsnet_open(struct net_device *dev) { int err; err = request_irq(dev->irq, &mipsnet_interrupt, IRQF_SHARED, dev->name, (void *) dev); if (err) { release_region(dev->base_addr, sizeof(struct mipsnet_regs)); return err; } netif_start_queue(dev); /* test interrupt handler */ outl(MIPSNET_INTCTL_TESTBIT, regaddr(dev, interruptControl)); return 0; } static int mipsnet_close(struct net_device *dev) { netif_stop_queue(dev); free_irq(dev->irq, dev); return 0; } static void mipsnet_set_mclist(struct net_device *dev) { } static int __init mipsnet_probe(struct device *dev) { struct net_device *netdev; int err; netdev = alloc_etherdev(0); if (!netdev) { err = -ENOMEM; goto out; } dev_set_drvdata(dev, netdev); netdev->open = mipsnet_open; netdev->stop = mipsnet_close; netdev->hard_start_xmit = mipsnet_xmit; netdev->set_multicast_list = mipsnet_set_mclist; /* * TODO: probe for these or load them from PARAM */ netdev->base_addr = 0x4200; netdev->irq = MIPS_CPU_IRQ_BASE + MIPSCPU_INT_MB0 + inl(regaddr(netdev, interruptInfo)); /* Get the io region now, get irq on open() */ if (!request_region(netdev->base_addr, sizeof(struct mipsnet_regs), "mipsnet")) { err = -EBUSY; goto out_free_netdev; } /* * Lacking any better mechanism to allocate a MAC address we use a * random one ... */ random_ether_addr(netdev->dev_addr); err = register_netdev(netdev); if (err) { printk(KERN_ERR "MIPSNet: failed to register netdev.\n"); goto out_free_region; } return 0; out_free_region: release_region(netdev->base_addr, sizeof(struct mipsnet_regs)); out_free_netdev: free_netdev(netdev); out: return err; } static int __devexit mipsnet_device_remove(struct device *device) { struct net_device *dev = dev_get_drvdata(device); unregister_netdev(dev); release_region(dev->base_addr, sizeof(struct mipsnet_regs)); free_netdev(dev); dev_set_drvdata(device, NULL); return 0; } static struct device_driver mipsnet_driver = { .name = mipsnet_string, .bus = &platform_bus_type, .probe = mipsnet_probe, .remove = __devexit_p(mipsnet_device_remove), }; static int __init mipsnet_init_module(void) { int err; printk(KERN_INFO "MIPSNet Ethernet driver. Version: %s. " "(c)2005 MIPS Technologies, Inc.\n", MIPSNET_VERSION); err = driver_register(&mipsnet_driver); if (err) printk(KERN_ERR "Driver registration failed\n"); return err; } static void __exit mipsnet_exit_module(void) { driver_unregister(&mipsnet_driver); } module_init(mipsnet_init_module); module_exit(mipsnet_exit_module);