m68k/atari: ARAnyM - Add support for network access

[petr: Second author]
[michael, geert: Cleanups and updates]

Signed-off-by: Milan Jurik <milan.jurik@xylab.cz>
Signed-off-by: Petr Stehlik <pstehlik@sophics.cz>
Signed-off-by: Michael Schmitz <schmitz@debian.org>
Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: netdev@vger.kernel.org

3 files changed, 279 insertions, 0 deletions

diff --git a/arch/m68k/Kconfig b/arch/m68k/Kconfig
index 6719c5629c5d..80df6ee7cac8 100644
--- a/arch/m68k/Kconfig
+++ b/arch/m68k/Kconfig
@@ -263,6 +263,14 @@ config NFCON
           which allows the console output to be redirected to the stderr
           output of ARAnyM.
 
+config NFETH
+        tristate "NatFeat Ethernet support"
+        depends on NET_ETHERNET && NATFEAT
+        help
+          Say Y to include support for the ARAnyM NatFeat network device
+          which will emulate a regular ethernet device while presenting an
+          ethertap device to the host system.
+
 comment "Processor type"
 
 config M68020
diff --git a/arch/m68k/emu/Makefile b/arch/m68k/emu/Makefile
index a83ef1e497b3..7dc201080308 100644
--- a/arch/m68k/emu/Makefile
+++ b/arch/m68k/emu/Makefile
@@ -6,3 +6,4 @@ obj-y			+= natfeat.o
 
 obj-$(CONFIG_NFBLOCK)   += nfblock.o
 obj-$(CONFIG_NFCON)     += nfcon.o
+obj-$(CONFIG_NFETH)     += nfeth.o
diff --git a/arch/m68k/emu/nfeth.c b/arch/m68k/emu/nfeth.c
new file mode 100644
index 000000000000..8b6e201b2c20
--- /dev/null
+++ b/arch/m68k/emu/nfeth.c
@@ -0,0 +1,270 @@
+/*
+ * atari_nfeth.c - ARAnyM ethernet card driver for GNU/Linux
+ *
+ * Copyright (c) 2005 Milan Jurik, Petr Stehlik of ARAnyM dev team
+ *
+ * Based on ARAnyM driver for FreeMiNT written by Standa Opichal
+ *
+ * This software may be used and distributed according to the terms of
+ * the GNU General Public License (GPL), incorporated herein by reference.
+ */
+
+#define DRV_VERSION     "0.3"
+#define DRV_RELDATE     "10/12/2005"
+
+#define pr_fmt(fmt)     KBUILD_MODNAME ": " fmt
+
+#include <linux/netdevice.h>
+#include <linux/etherdevice.h>
+#include <linux/module.h>
+#include <asm/natfeat.h>
+#include <asm/virtconvert.h>
+
+enum {
+        GET_VERSION = 0,/* no parameters, return NFAPI_VERSION in d0 */
+        XIF_INTLEVEL,   /* no parameters, return Interrupt Level in d0 */
+        XIF_IRQ,        /* acknowledge interrupt from host */
+        XIF_START,      /* (ethX), called on 'ifup', start receiver thread */
+        XIF_STOP,       /* (ethX), called on 'ifdown', stop the thread */
+        XIF_READLENGTH, /* (ethX), return size of network data block to read */
+        XIF_READBLOCK,  /* (ethX, buffer, size), read block of network data */
+        XIF_WRITEBLOCK, /* (ethX, buffer, size), write block of network data */
+        XIF_GET_MAC,    /* (ethX, buffer, size), return MAC HW addr in buffer */
+        XIF_GET_IPHOST, /* (ethX, buffer, size), return IP address of host */
+        XIF_GET_IPATARI,/* (ethX, buffer, size), return IP address of atari */
+        XIF_GET_NETMASK /* (ethX, buffer, size), return IP netmask */
+};
+
+#define MAX_UNIT        8
+
+/* These identify the driver base version and may not be removed. */
+static const char version[] __devinitdata =
+        KERN_INFO KBUILD_MODNAME ".c:v" DRV_VERSION " " DRV_RELDATE
+        " S.Opichal, M.Jurik, P.Stehlik\n"
+        KERN_INFO " http://aranym.org/\n";
+
+MODULE_AUTHOR("Milan Jurik");
+MODULE_DESCRIPTION("Atari NFeth driver");
+MODULE_LICENSE("GPL");
+/*
+MODULE_PARM(nfeth_debug, "i");
+MODULE_PARM_DESC(nfeth_debug, "nfeth_debug level (1-2)");
+*/
+
+
+static long nfEtherID;
+static int nfEtherIRQ;
+
+struct nfeth_private {
+        int ethX;
+};
+
+static struct net_device *nfeth_dev[MAX_UNIT];
+
+static int nfeth_open(struct net_device *dev)
+{
+        struct nfeth_private *priv = netdev_priv(dev);
+        int res;
+
+        res = nf_call(nfEtherID + XIF_START, priv->ethX);
+        netdev_dbg(dev, "%s: %d\n", __func__, res);
+
+        /* Ready for data */
+        netif_start_queue(dev);
+
+        return 0;
+}
+
+static int nfeth_stop(struct net_device *dev)
+{
+        struct nfeth_private *priv = netdev_priv(dev);
+
+        /* No more data */
+        netif_stop_queue(dev);
+
+        nf_call(nfEtherID + XIF_STOP, priv->ethX);
+
+        return 0;
+}
+
+/*
+ * Read a packet out of the adapter and pass it to the upper layers
+ */
+static inline void recv_packet(struct net_device *dev)
+{
+        struct nfeth_private *priv = netdev_priv(dev);
+        unsigned short pktlen;
+        struct sk_buff *skb;
+
+        /* read packet length (excluding 32 bit crc) */
+        pktlen = nf_call(nfEtherID + XIF_READLENGTH, priv->ethX);
+
+        netdev_dbg(dev, "%s: %u\n", __func__, pktlen);
+
+        if (!pktlen) {
+                netdev_dbg(dev, "%s: pktlen == 0\n", __func__);
+                dev->stats.rx_errors++;
+                return;
+        }
+
+        skb = dev_alloc_skb(pktlen + 2);
+        if (!skb) {
+                netdev_dbg(dev, "%s: out of mem (buf_alloc failed)\n",
+                           __func__);
+                dev->stats.rx_dropped++;
+                return;
+        }
+
+        skb->dev = dev;
+        skb_reserve(skb, 2);            /* 16 Byte align  */
+        skb_put(skb, pktlen);           /* make room */
+        nf_call(nfEtherID + XIF_READBLOCK, priv->ethX, virt_to_phys(skb->data),
+                pktlen);
+
+        skb->protocol = eth_type_trans(skb, dev);
+        netif_rx(skb);
+        dev->last_rx = jiffies;
+        dev->stats.rx_packets++;
+        dev->stats.rx_bytes += pktlen;
+
+        /* and enqueue packet */
+        return;
+}
+
+static irqreturn_t nfeth_interrupt(int irq, void *dev_id)
+{
+        int i, m, mask;
+
+        mask = nf_call(nfEtherID + XIF_IRQ, 0);
+        for (i = 0, m = 1; i < MAX_UNIT; m <<= 1, i++) {
+                if (mask & m && nfeth_dev[i]) {
+                        recv_packet(nfeth_dev[i]);
+                        nf_call(nfEtherID + XIF_IRQ, m);
+                }
+        }
+        return IRQ_HANDLED;
+}
+
+static int nfeth_xmit(struct sk_buff *skb, struct net_device *dev)
+{
+        unsigned int len;
+        char *data, shortpkt[ETH_ZLEN];
+        struct nfeth_private *priv = netdev_priv(dev);
+
+        data = skb->data;
+        len = skb->len;
+        if (len < ETH_ZLEN) {
+                memset(shortpkt, 0, ETH_ZLEN);
+                memcpy(shortpkt, data, len);
+                data = shortpkt;
+                len = ETH_ZLEN;
+        }
+
+        netdev_dbg(dev, "%s: send %u bytes\n", __func__, len);
+        nf_call(nfEtherID + XIF_WRITEBLOCK, priv->ethX, virt_to_phys(data),
+                len);
+
+        dev->stats.tx_packets++;
+        dev->stats.tx_bytes += len;
+
+        dev_kfree_skb(skb);
+        return 0;
+}
+
+static void nfeth_tx_timeout(struct net_device *dev)
+{
+        dev->stats.tx_errors++;
+        netif_wake_queue(dev);
+}
+
+static const struct net_device_ops nfeth_netdev_ops = {
+        .ndo_open               = nfeth_open,
+        .ndo_stop               = nfeth_stop,
+        .ndo_start_xmit         = nfeth_xmit,
+        .ndo_tx_timeout         = nfeth_tx_timeout,
+        .ndo_validate_addr      = eth_validate_addr,
+        .ndo_change_mtu         = eth_change_mtu,
+        .ndo_set_mac_address    = eth_mac_addr,
+};
+
+static struct net_device * __init nfeth_probe(int unit)
+{
+        struct net_device *dev;
+        struct nfeth_private *priv;
+        char mac[ETH_ALEN], host_ip[32], local_ip[32];
+        int err;
+
+        if (!nf_call(nfEtherID + XIF_GET_MAC, unit, mac, ETH_ALEN))
+                return NULL;
+
+        dev = alloc_etherdev(sizeof(struct nfeth_private));
+        if (!dev)
+                return NULL;
+
+        dev->irq = nfEtherIRQ;
+        dev->netdev_ops = &nfeth_netdev_ops;
+
+        dev->flags |= NETIF_F_NO_CSUM;
+        memcpy(dev->dev_addr, mac, ETH_ALEN);
+
+        priv = netdev_priv(dev);
+        priv->ethX = unit;
+
+        err = register_netdev(dev);
+        if (err) {
+                free_netdev(dev);
+                return NULL;
+        }
+
+        nf_call(nfEtherID + XIF_GET_IPHOST, unit,
+                host_ip, sizeof(host_ip));
+        nf_call(nfEtherID + XIF_GET_IPATARI, unit,
+                local_ip, sizeof(local_ip));
+
+        netdev_info(dev, KBUILD_MODNAME " addr:%s (%s) HWaddr:%pM\n", host_ip,
+                    local_ip, mac);
+
+        return dev;
+}
+
+static int __init nfeth_init(void)
+{
+        long ver;
+        int error, i;
+
+        nfEtherID = nf_get_id("ETHERNET");
+        if (!nfEtherID)
+                return -ENODEV;
+
+        ver = nf_call(nfEtherID + GET_VERSION);
+        pr_info("API %lu\n", ver);
+
+        nfEtherIRQ = nf_call(nfEtherID + XIF_INTLEVEL);
+        error = request_irq(nfEtherIRQ, nfeth_interrupt, IRQF_SHARED,
+                            "eth emu", nfeth_interrupt);
+        if (error) {
+                pr_err("request for irq %d failed %d", nfEtherIRQ, error);
+                return error;
+        }
+
+        for (i = 0; i < MAX_UNIT; i++)
+                nfeth_dev[i] = nfeth_probe(i);
+
+        return 0;
+}
+
+static void __exit nfeth_cleanup(void)
+{
+        int i;
+
+        for (i = 0; i < MAX_UNIT; i++) {
+                if (nfeth_dev[i]) {
+                        unregister_netdev(nfeth_dev[0]);
+                        free_netdev(nfeth_dev[0]);
+                }
+        }
+        free_irq(nfEtherIRQ, nfeth_interrupt);
+}
+
+module_init(nfeth_init);
+module_exit(nfeth_cleanup);