[PATCH] mipsnet: Virtual ethernet driver for MIPSsim.
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
drivers/net/Kconfig | 8 +
drivers/net/Makefile | 1
drivers/net/mipsnet.c | 371 ++++++++++++++++++++++++++++++++++++++++++++++++++
drivers/net/mipsnet.h | 127 +++++++++++++++++
4 files changed, 507 insertions(+)
Signed-off-by: Jeff Garzik <jgarzik@pobox.com>
diff --git a/drivers/net/mipsnet.c b/drivers/net/mipsnet.c
new file mode 100644
index 0000000..f79f7ee
--- /dev/null
+++ b/drivers/net/mipsnet.c
@@ -0,0 +1,371 @@
+/*
+ * 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.
+ */
+
+#define DEBUG
+
+#include <linux/init.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/netdevice.h>
+#include <linux/sched.h>
+#include <linux/etherdevice.h>
+#include <linux/netdevice.h>
+#include <asm/io.h>
+#include <asm/mips-boards/simint.h>
+
+#include "mipsnet.h" /* actual device IO mapping */
+
+#define MIPSNET_VERSION "2005-06-20"
+
+#define mipsnet_reg_address(dev, field) (dev->base_addr + field_offset(field))
+
+struct mipsnet_priv {
+ struct net_device_stats stats;
+};
+
+static struct platform_device *mips_plat_dev;
+
+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)
+{
+ uint32_t available_len = inl(mipsnet_reg_address(dev, rxDataCount));
+ if (available_len < len)
+ return -EFAULT;
+
+ for (; len > 0; len--, kdata++) {
+ *kdata = inb(mipsnet_reg_address(dev, rxDataBuffer));
+ }
+
+ return inl(mipsnet_reg_address(dev, rxDataCount));
+}
+
+static inline ssize_t mipsnet_put_todevice(struct net_device *dev,
+ struct sk_buff *skb)
+{
+ int count_to_go = skb->len;
+ char *buf_ptr = skb->data;
+ struct mipsnet_priv *mp = netdev_priv(dev);
+
+ pr_debug("%s: %s(): telling MIPSNET txDataCount(%d)\n",
+ dev->name, __FUNCTION__, skb->len);
+
+ outl(skb->len, mipsnet_reg_address(dev, txDataCount));
+
+ pr_debug("%s: %s(): sending data to MIPSNET txDataBuffer(%d)\n",
+ dev->name, __FUNCTION__, skb->len);
+
+ for (; count_to_go; buf_ptr++, count_to_go--) {
+ outb(*buf_ptr, mipsnet_reg_address(dev, txDataBuffer));
+ }
+
+ mp->stats.tx_packets++;
+ mp->stats.tx_bytes += skb->len;
+
+ return skb->len;
+}
+
+static int mipsnet_xmit(struct sk_buff *skb, struct net_device *dev)
+{
+ pr_debug("%s:%s(): transmitting %d bytes\n",
+ dev->name, __FUNCTION__, skb->len);
+
+ /* 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 count)
+{
+ struct sk_buff *skb;
+ size_t len = count;
+ struct mipsnet_priv *mp = netdev_priv(dev);
+
+ if (!(skb = alloc_skb(len + 2, GFP_KERNEL))) {
+ mp->stats.rx_dropped++;
+ return -ENOMEM;
+ }
+
+ skb_reserve(skb, 2);
+ if (ioiocpy_frommipsnet(dev, skb_put(skb, len), len))
+ return -EFAULT;
+
+ skb->dev = dev;
+ skb->protocol = eth_type_trans(skb, dev);
+ skb->ip_summed = CHECKSUM_UNNECESSARY;
+
+ pr_debug("%s:%s(): pushing RXed data to kernel\n",
+ dev->name, __FUNCTION__);
+ netif_rx(skb);
+
+ mp->stats.rx_packets++;
+ mp->stats.rx_bytes += len;
+
+ return count;
+}
+
+static irqreturn_t
+mipsnet_interrupt(int irq, void *dev_id, struct pt_regs *regs)
+{
+ struct net_device *dev = dev_id;
+
+ irqreturn_t retval = IRQ_NONE;
+ uint64_t interruptFlags;
+
+ if (irq == dev->irq) {
+ pr_debug("%s:%s(): irq %d for device\n",
+ dev->name, __FUNCTION__, irq);
+
+ retval = IRQ_HANDLED;
+
+ interruptFlags =
+ inl(mipsnet_reg_address(dev, interruptControl));
+ pr_debug("%s:%s(): intCtl=0x%016llx\n", dev->name,
+ __FUNCTION__, interruptFlags);
+
+ if (interruptFlags & MIPSNET_INTCTL_TXDONE) {
+ pr_debug("%s:%s(): got TXDone\n",
+ dev->name, __FUNCTION__);
+ outl(MIPSNET_INTCTL_TXDONE,
+ mipsnet_reg_address(dev, interruptControl));
+ // only one packet at a time, we are done.
+ netif_wake_queue(dev);
+ } else if (interruptFlags & MIPSNET_INTCTL_RXDONE) {
+ pr_debug("%s:%s(): got RX data\n",
+ dev->name, __FUNCTION__);
+ mipsnet_get_fromdev(dev,
+ inl(mipsnet_reg_address(dev, rxDataCount)));
+ pr_debug("%s:%s(): clearing RX int\n",
+ dev->name, __FUNCTION__);
+ outl(MIPSNET_INTCTL_RXDONE,
+ mipsnet_reg_address(dev, interruptControl));
+
+ } else if (interruptFlags & MIPSNET_INTCTL_TESTBIT) {
+ pr_debug("%s:%s(): got test interrupt\n",
+ dev->name, __FUNCTION__);
+ // TESTBIT is cleared on read.
+ // And takes effect after a write with 0
+ outl(0, mipsnet_reg_address(dev, interruptControl));
+ } else {
+ pr_debug("%s:%s(): no valid fags 0x%016llx\n",
+ dev->name, __FUNCTION__, interruptFlags);
+ // Maybe shared IRQ, just ignore, no clearing.
+ retval = IRQ_NONE;
+ }
+
+ } else {
+ printk(KERN_INFO "%s: %s(): irq %d for unknown device\n",
+ dev->name, __FUNCTION__, irq);
+ retval = IRQ_NONE;
+ }
+ return retval;
+} //mipsnet_interrupt()
+
+static int mipsnet_open(struct net_device *dev)
+{
+ int err;
+ pr_debug("%s: mipsnet_open\n", dev->name);
+
+ err = request_irq(dev->irq, &mipsnet_interrupt,
+ SA_SHIRQ, dev->name, (void *) dev);
+
+ if (err) {
+ pr_debug("%s: %s(): can't get irq %d\n",
+ dev->name, __FUNCTION__, dev->irq);
+ release_region(dev->base_addr, MIPSNET_IO_EXTENT);
+ return err;
+ }
+
+ pr_debug("%s: %s(): got IO region at 0x%04lx and irq %d for dev.\n",
+ dev->name, __FUNCTION__, dev->base_addr, dev->irq);
+
+
+ netif_start_queue(dev);
+
+ // test interrupt handler
+ outl(MIPSNET_INTCTL_TESTBIT,
+ mipsnet_reg_address(dev, interruptControl));
+
+
+ return 0;
+}
+
+static int mipsnet_close(struct net_device *dev)
+{
+ pr_debug("%s: %s()\n", dev->name, __FUNCTION__);
+ netif_stop_queue(dev);
+ return 0;
+}
+
+static struct net_device_stats *mipsnet_get_stats(struct net_device *dev)
+{
+ struct mipsnet_priv *mp = netdev_priv(dev);
+
+ return &mp->stats;
+}
+
+static void mipsnet_set_mclist(struct net_device *dev)
+{
+ // we don't do anything
+ return;
+}
+
+static int __init mipsnet_probe(struct device *dev)
+{
+ struct net_device *netdev;
+ int err;
+
+ netdev = alloc_etherdev(sizeof(struct mipsnet_priv));
+ 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->get_stats = mipsnet_get_stats;
+ netdev->set_multicast_list = mipsnet_set_mclist;
+
+ /*
+ * TODO: probe for these or load them from PARAM
+ */
+ netdev->base_addr = 0x4200;
+ netdev->irq = MIPSCPU_INT_BASE + MIPSCPU_INT_MB0 +
+ inl(mipsnet_reg_address(netdev, interruptInfo));
+
+ // Get the io region now, get irq on open()
+ if (!request_region(netdev->base_addr, MIPSNET_IO_EXTENT, "mipsnet")) {
+ pr_debug("%s: %s(): IO region {start: 0x%04lux, len: %d} "
+ "for dev is not availble.\n", netdev->name,
+ __FUNCTION__, netdev->base_addr, MIPSNET_IO_EXTENT);
+ 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, MIPSNET_IO_EXTENT);
+
+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, MIPSNET_IO_EXTENT);
+ 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 void mipsnet_platform_release(struct device *device)
+{
+ struct platform_device *pldev;
+
+ /* free device */
+ pldev = to_platform_device(device);
+ kfree(pldev);
+}
+
+static int __init mipsnet_init_module(void)
+{
+ struct platform_device *pldev;
+ int err;
+
+ printk(KERN_INFO "MIPSNet Ethernet driver. Version: %s. "
+ "(c)2005 MIPS Technologies, Inc.\n", MIPSNET_VERSION);
+
+ if (driver_register(&mipsnet_driver)) {
+ printk(KERN_ERR "Driver registration failed\n");
+ err = -ENODEV;
+ goto out;
+ }
+
+ if (!(pldev = kmalloc (sizeof (*pldev), GFP_KERNEL))) {
+ err = -ENOMEM;
+ goto out_unregister_driver;
+ }
+
+ memset (pldev, 0, sizeof (*pldev));
+ pldev->name = mipsnet_string;
+ pldev->id = 0;
+ pldev->dev.release = mipsnet_platform_release;
+
+ if (platform_device_register(pldev)) {
+ err = -ENODEV;
+ goto out_free_pldev;
+ }
+
+ if (!pldev->dev.driver) {
+ /*
+ * The driver was not bound to this device, there was
+ * no hardware at this address. Unregister it, as the
+ * release fuction will take care of freeing the
+ * allocated structure
+ */
+ platform_device_unregister (pldev);
+ }
+
+ mips_plat_dev = pldev;
+
+ return 0;
+
+out_free_pldev:
+ kfree(pldev);
+
+out_unregister_driver:
+ driver_unregister(&mipsnet_driver);
+out:
+ return err;
+}
+
+static void __exit mipsnet_exit_module(void)
+{
+ pr_debug("MIPSNet Ethernet driver exiting\n");
+
+ driver_unregister(&mipsnet_driver);
+}
+
+module_init(mipsnet_init_module);
+module_exit(mipsnet_exit_module);