mipsnet: Move the MIPS driver

Move the MIPS drivers into drivers/net/ethernet/ and
make the necessary Kconfig and Makefile changes.

Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>

3 files changed, 355 insertions, 0 deletions

diff --git a/drivers/net/ethernet/Kconfig b/drivers/net/ethernet/Kconfig
index dae10a3eca78..f1509a598102 100644
--- a/drivers/net/ethernet/Kconfig
+++ b/drivers/net/ethernet/Kconfig
@@ -55,6 +55,15 @@ config KORINA
 source "drivers/net/ethernet/marvell/Kconfig"
 source "drivers/net/ethernet/mellanox/Kconfig"
 source "drivers/net/ethernet/micrel/Kconfig"
+
+config MIPS_SIM_NET
+	tristate "MIPS simulator Network device"
+	depends on MIPS_SIM
+	---help---
+	  The MIPSNET device is a simple Ethernet network device which is
+	  emulated by the MIPS Simulator.
+	  If you are not using a MIPSsim or are unsure, say N.
+
 source "drivers/net/ethernet/myricom/Kconfig"
 source "drivers/net/ethernet/natsemi/Kconfig"
 source "drivers/net/ethernet/8390/Kconfig"
diff --git a/drivers/net/ethernet/Makefile b/drivers/net/ethernet/Makefile
index ddf097df9238..50fc50a49295 100644
--- a/drivers/net/ethernet/Makefile
+++ b/drivers/net/ethernet/Makefile
@@ -29,6 +29,7 @@ obj-$(CONFIG_KORINA) += korina.o
 obj-$(CONFIG_NET_VENDOR_MARVELL) += marvell/
 obj-$(CONFIG_NET_VENDOR_MELLANOX) += mellanox/
 obj-$(CONFIG_NET_VENDOR_MICREL) += micrel/
+obj-$(CONFIG_MIPS_SIM_NET) += mipsnet.o
 obj-$(CONFIG_NET_VENDOR_MYRI) += myricom/
 obj-$(CONFIG_NET_VENDOR_NATSEMI) += natsemi/
 obj-$(CONFIG_NET_VENDOR_NUVOTON) += nuvoton/
diff --git a/drivers/net/ethernet/mipsnet.c b/drivers/net/ethernet/mipsnet.c
new file mode 100644
index 000000000000..004e64ab1f95
--- /dev/null
+++ b/drivers/net/ethernet/mipsnet.c
@@ -0,0 +1,345 @@
+/*
+ * 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/interrupt.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 NETDEV_TX_OK;
+}
+
+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, __func__, 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 const struct net_device_ops mipsnet_netdev_ops = {
+	.ndo_open		= mipsnet_open,
+	.ndo_stop		= mipsnet_close,
+	.ndo_start_xmit		= mipsnet_xmit,
+	.ndo_set_multicast_list	= mipsnet_set_mclist,
+	.ndo_change_mtu		= eth_change_mtu,
+	.ndo_validate_addr	= eth_validate_addr,
+	.ndo_set_mac_address	= eth_mac_addr,
+};
+
+static int __devinit mipsnet_probe(struct platform_device *dev)
+{
+	struct net_device *netdev;
+	int err;
+
+	netdev = alloc_etherdev(0);
+	if (!netdev) {
+		err = -ENOMEM;
+		goto out;
+	}
+
+	platform_set_drvdata(dev, netdev);
+
+	netdev->netdev_ops = &mipsnet_netdev_ops;
+
+	/*
+	 * 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 platform_device *device)
+{
+	struct net_device *dev = platform_get_drvdata(device);
+
+	unregister_netdev(dev);
+	release_region(dev->base_addr, sizeof(struct mipsnet_regs));
+	free_netdev(dev);
+	platform_set_drvdata(device, NULL);
+
+	return 0;
+}
+
+static struct platform_driver mipsnet_driver = {
+	.driver = {
+		.name		= mipsnet_string,
+		.owner		= THIS_MODULE,
+	},
+	.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 = platform_driver_register(&mipsnet_driver);
+	if (err)
+		printk(KERN_ERR "Driver registration failed\n");
+
+	return err;
+}
+
+static void __exit mipsnet_exit_module(void)
+{
+	platform_driver_unregister(&mipsnet_driver);
+}
+
+module_init(mipsnet_init_module);
+module_exit(mipsnet_exit_module);