[PATCH] Add rapidio net driver

Adds an "Ethernet" driver which sends Ethernet packets over the standard
RapidIO messaging.  This depends on the core RIO patch for mailbox/doorbell
access.

Signed-off-by: Matt Porter <mporter@kernel.crashing.org>
Cc: Jeff Garzik <jgarzik@pobox.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Jeff Garzik <jgarzik@pobox.com>

3 files changed, 589 insertions, 0 deletions

diff --git a/drivers/net/Kconfig b/drivers/net/Kconfig
index 54fff9c2e802..82603e419d76 100644
--- a/drivers/net/Kconfig
+++ b/drivers/net/Kconfig
@@ -2235,6 +2235,20 @@ config ISERIES_VETH
         tristate "iSeries Virtual Ethernet driver support"
         depends on PPC_ISERIES
 
+config RIONET
+        tristate "RapidIO Ethernet over messaging driver support"
+        depends on NETDEVICES && RAPIDIO
+
+config RIONET_TX_SIZE
+        int "Number of outbound queue entries"
+        depends on RIONET
+        default "128"
+
+config RIONET_RX_SIZE
+        int "Number of inbound queue entries"
+        depends on RIONET
+        default "128"
+
 config FDDI
         bool "FDDI driver support"
         depends on (PCI || EISA)
diff --git a/drivers/net/Makefile b/drivers/net/Makefile
index 8645c843cf4d..e6acba68923a 100644
--- a/drivers/net/Makefile
+++ b/drivers/net/Makefile
@@ -63,6 +63,7 @@ obj-$(CONFIG_SKFP) += skfp/
 obj-$(CONFIG_VIA_RHINE) += via-rhine.o
 obj-$(CONFIG_VIA_VELOCITY) += via-velocity.o
 obj-$(CONFIG_ADAPTEC_STARFIRE) += starfire.o
+obj-$(CONFIG_RIONET) += rionet.o
 
 #
 # end link order section
diff --git a/drivers/net/rionet.c b/drivers/net/rionet.c
new file mode 100644
index 000000000000..12cde0604580
--- /dev/null
+++ b/drivers/net/rionet.c
@@ -0,0 +1,574 @@
+/*
+ * rionet - Ethernet driver over RapidIO messaging services
+ *
+ * Copyright 2005 MontaVista Software, Inc.
+ * Matt Porter <mporter@kernel.crashing.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.
+ */
+
+#include <linux/module.h>
+#include <linux/kernel.h>
+#include <linux/dma-mapping.h>
+#include <linux/delay.h>
+#include <linux/rio.h>
+#include <linux/rio_drv.h>
+#include <linux/rio_ids.h>
+
+#include <linux/netdevice.h>
+#include <linux/etherdevice.h>
+#include <linux/skbuff.h>
+#include <linux/crc32.h>
+#include <linux/ethtool.h>
+
+#define DRV_NAME        "rionet"
+#define DRV_VERSION     "0.2"
+#define DRV_AUTHOR      "Matt Porter <mporter@kernel.crashing.org>"
+#define DRV_DESC        "Ethernet over RapidIO"
+
+MODULE_AUTHOR(DRV_AUTHOR);
+MODULE_DESCRIPTION(DRV_DESC);
+MODULE_LICENSE("GPL");
+
+#define RIONET_DEFAULT_MSGLEVEL \
+                        (NETIF_MSG_DRV          | \
+                         NETIF_MSG_LINK         | \
+                         NETIF_MSG_RX_ERR       | \
+                         NETIF_MSG_TX_ERR)
+
+#define RIONET_DOORBELL_JOIN    0x1000
+#define RIONET_DOORBELL_LEAVE   0x1001
+
+#define RIONET_MAILBOX          0
+
+#define RIONET_TX_RING_SIZE     CONFIG_RIONET_TX_SIZE
+#define RIONET_RX_RING_SIZE     CONFIG_RIONET_RX_SIZE
+
+static LIST_HEAD(rionet_peers);
+
+struct rionet_private {
+        struct rio_mport *mport;
+        struct sk_buff *rx_skb[RIONET_RX_RING_SIZE];
+        struct sk_buff *tx_skb[RIONET_TX_RING_SIZE];
+        struct net_device_stats stats;
+        int rx_slot;
+        int tx_slot;
+        int tx_cnt;
+        int ack_slot;
+        spinlock_t lock;
+        spinlock_t tx_lock;
+        u32 msg_enable;
+};
+
+struct rionet_peer {
+        struct list_head node;
+        struct rio_dev *rdev;
+        struct resource *res;
+};
+
+static int rionet_check = 0;
+static int rionet_capable = 1;
+
+/*
+ * This is a fast lookup table for for translating TX
+ * Ethernet packets into a destination RIO device. It
+ * could be made into a hash table to save memory depending
+ * on system trade-offs.
+ */
+static struct rio_dev *rionet_active[RIO_MAX_ROUTE_ENTRIES];
+
+#define is_rionet_capable(pef, src_ops, dst_ops)                \
+                        ((pef & RIO_PEF_INB_MBOX) &&            \
+                         (pef & RIO_PEF_INB_DOORBELL) &&        \
+                         (src_ops & RIO_SRC_OPS_DOORBELL) &&    \
+                         (dst_ops & RIO_DST_OPS_DOORBELL))
+#define dev_rionet_capable(dev) \
+        is_rionet_capable(dev->pef, dev->src_ops, dev->dst_ops)
+
+#define RIONET_MAC_MATCH(x)     (*(u32 *)x == 0x00010001)
+#define RIONET_GET_DESTID(x)    (*(u16 *)(x + 4))
+
+static struct net_device_stats *rionet_stats(struct net_device *ndev)
+{
+        struct rionet_private *rnet = ndev->priv;
+        return &rnet->stats;
+}
+
+static int rionet_rx_clean(struct net_device *ndev)
+{
+        int i;
+        int error = 0;
+        struct rionet_private *rnet = ndev->priv;
+        void *data;
+
+        i = rnet->rx_slot;
+
+        do {
+                if (!rnet->rx_skb[i])
+                        continue;
+
+                if (!(data = rio_get_inb_message(rnet->mport, RIONET_MAILBOX)))
+                        break;
+
+                rnet->rx_skb[i]->data = data;
+                skb_put(rnet->rx_skb[i], RIO_MAX_MSG_SIZE);
+                rnet->rx_skb[i]->dev = ndev;
+                rnet->rx_skb[i]->protocol =
+                    eth_type_trans(rnet->rx_skb[i], ndev);
+                error = netif_rx(rnet->rx_skb[i]);
+
+                if (error == NET_RX_DROP) {
+                        rnet->stats.rx_dropped++;
+                } else if (error == NET_RX_BAD) {
+                        if (netif_msg_rx_err(rnet))
+                                printk(KERN_WARNING "%s: bad rx packet\n",
+                                       DRV_NAME);
+                        rnet->stats.rx_errors++;
+                } else {
+                        rnet->stats.rx_packets++;
+                        rnet->stats.rx_bytes += RIO_MAX_MSG_SIZE;
+                }
+
+        } while ((i = (i + 1) % RIONET_RX_RING_SIZE) != rnet->rx_slot);
+
+        return i;
+}
+
+static void rionet_rx_fill(struct net_device *ndev, int end)
+{
+        int i;
+        struct rionet_private *rnet = ndev->priv;
+
+        i = rnet->rx_slot;
+        do {
+                rnet->rx_skb[i] = dev_alloc_skb(RIO_MAX_MSG_SIZE);
+
+                if (!rnet->rx_skb[i])
+                        break;
+
+                rio_add_inb_buffer(rnet->mport, RIONET_MAILBOX,
+                                   rnet->rx_skb[i]->data);
+        } while ((i = (i + 1) % RIONET_RX_RING_SIZE) != end);
+
+        rnet->rx_slot = i;
+}
+
+static int rionet_queue_tx_msg(struct sk_buff *skb, struct net_device *ndev,
+                               struct rio_dev *rdev)
+{
+        struct rionet_private *rnet = ndev->priv;
+
+        rio_add_outb_message(rnet->mport, rdev, 0, skb->data, skb->len);
+        rnet->tx_skb[rnet->tx_slot] = skb;
+
+        rnet->stats.tx_packets++;
+        rnet->stats.tx_bytes += skb->len;
+
+        if (++rnet->tx_cnt == RIONET_TX_RING_SIZE)
+                netif_stop_queue(ndev);
+
+        ++rnet->tx_slot;
+        rnet->tx_slot &= (RIONET_TX_RING_SIZE - 1);
+
+        if (netif_msg_tx_queued(rnet))
+                printk(KERN_INFO "%s: queued skb %8.8x len %8.8x\n", DRV_NAME,
+                       (u32) skb, skb->len);
+
+        return 0;
+}
+
+static int rionet_start_xmit(struct sk_buff *skb, struct net_device *ndev)
+{
+        int i;
+        struct rionet_private *rnet = ndev->priv;
+        struct ethhdr *eth = (struct ethhdr *)skb->data;
+        u16 destid;
+        unsigned long flags;
+
+        local_irq_save(flags);
+        if (!spin_trylock(&rnet->tx_lock)) {
+                local_irq_restore(flags);
+                return NETDEV_TX_LOCKED;
+        }
+
+        if ((rnet->tx_cnt + 1) > RIONET_TX_RING_SIZE) {
+                netif_stop_queue(ndev);
+                spin_unlock_irqrestore(&rnet->tx_lock, flags);
+                printk(KERN_ERR "%s: BUG! Tx Ring full when queue awake!\n",
+                       ndev->name);
+                return NETDEV_TX_BUSY;
+        }
+
+        if (eth->h_dest[0] & 0x01) {
+                for (i = 0; i < RIO_MAX_ROUTE_ENTRIES; i++)
+                        if (rionet_active[i])
+                                rionet_queue_tx_msg(skb, ndev,
+                                                    rionet_active[i]);
+        } else if (RIONET_MAC_MATCH(eth->h_dest)) {
+                destid = RIONET_GET_DESTID(eth->h_dest);
+                if (rionet_active[destid])
+                        rionet_queue_tx_msg(skb, ndev, rionet_active[destid]);
+        }
+
+        spin_unlock_irqrestore(&rnet->tx_lock, flags);
+
+        return 0;
+}
+
+static void rionet_dbell_event(struct rio_mport *mport, void *dev_id, u16 sid, u16 tid,
+                               u16 info)
+{
+        struct net_device *ndev = dev_id;
+        struct rionet_private *rnet = ndev->priv;
+        struct rionet_peer *peer;
+
+        if (netif_msg_intr(rnet))
+                printk(KERN_INFO "%s: doorbell sid %4.4x tid %4.4x info %4.4x",
+                       DRV_NAME, sid, tid, info);
+        if (info == RIONET_DOORBELL_JOIN) {
+                if (!rionet_active[sid]) {
+                        list_for_each_entry(peer, &rionet_peers, node) {
+                                if (peer->rdev->destid == sid)
+                                        rionet_active[sid] = peer->rdev;
+                        }
+                        rio_mport_send_doorbell(mport, sid,
+                                                RIONET_DOORBELL_JOIN);
+                }
+        } else if (info == RIONET_DOORBELL_LEAVE) {
+                rionet_active[sid] = NULL;
+        } else {
+                if (netif_msg_intr(rnet))
+                        printk(KERN_WARNING "%s: unhandled doorbell\n",
+                               DRV_NAME);
+        }
+}
+
+static void rionet_inb_msg_event(struct rio_mport *mport, void *dev_id, int mbox, int slot)
+{
+        int n;
+        struct net_device *ndev = dev_id;
+        struct rionet_private *rnet = (struct rionet_private *)ndev->priv;
+
+        if (netif_msg_intr(rnet))
+                printk(KERN_INFO "%s: inbound message event, mbox %d slot %d\n",
+                       DRV_NAME, mbox, slot);
+
+        spin_lock(&rnet->lock);
+        if ((n = rionet_rx_clean(ndev)) != rnet->rx_slot)
+                rionet_rx_fill(ndev, n);
+        spin_unlock(&rnet->lock);
+}
+
+static void rionet_outb_msg_event(struct rio_mport *mport, void *dev_id, int mbox, int slot)
+{
+        struct net_device *ndev = dev_id;
+        struct rionet_private *rnet = ndev->priv;
+
+        spin_lock(&rnet->lock);
+
+        if (netif_msg_intr(rnet))
+                printk(KERN_INFO
+                       "%s: outbound message event, mbox %d slot %d\n",
+                       DRV_NAME, mbox, slot);
+
+        while (rnet->tx_cnt && (rnet->ack_slot != slot)) {
+                /* dma unmap single */
+                dev_kfree_skb_irq(rnet->tx_skb[rnet->ack_slot]);
+                rnet->tx_skb[rnet->ack_slot] = NULL;
+                ++rnet->ack_slot;
+                rnet->ack_slot &= (RIONET_TX_RING_SIZE - 1);
+                rnet->tx_cnt--;
+        }
+
+        if (rnet->tx_cnt < RIONET_TX_RING_SIZE)
+                netif_wake_queue(ndev);
+
+        spin_unlock(&rnet->lock);
+}
+
+static int rionet_open(struct net_device *ndev)
+{
+        int i, rc = 0;
+        struct rionet_peer *peer, *tmp;
+        u32 pwdcsr;
+        struct rionet_private *rnet = ndev->priv;
+
+        if (netif_msg_ifup(rnet))
+                printk(KERN_INFO "%s: open\n", DRV_NAME);
+
+        if ((rc = rio_request_inb_dbell(rnet->mport,
+                                        (void *)ndev,
+                                        RIONET_DOORBELL_JOIN,
+                                        RIONET_DOORBELL_LEAVE,
+                                        rionet_dbell_event)) < 0)
+                goto out;
+
+        if ((rc = rio_request_inb_mbox(rnet->mport,
+                                       (void *)ndev,
+                                       RIONET_MAILBOX,
+                                       RIONET_RX_RING_SIZE,
+                                       rionet_inb_msg_event)) < 0)
+                goto out;
+
+        if ((rc = rio_request_outb_mbox(rnet->mport,
+                                        (void *)ndev,
+                                        RIONET_MAILBOX,
+                                        RIONET_TX_RING_SIZE,
+                                        rionet_outb_msg_event)) < 0)
+                goto out;
+
+        /* Initialize inbound message ring */
+        for (i = 0; i < RIONET_RX_RING_SIZE; i++)
+                rnet->rx_skb[i] = NULL;
+        rnet->rx_slot = 0;
+        rionet_rx_fill(ndev, 0);
+
+        rnet->tx_slot = 0;
+        rnet->tx_cnt = 0;
+        rnet->ack_slot = 0;
+
+        netif_carrier_on(ndev);
+        netif_start_queue(ndev);
+
+        list_for_each_entry_safe(peer, tmp, &rionet_peers, node) {
+                if (!(peer->res = rio_request_outb_dbell(peer->rdev,
+                                                         RIONET_DOORBELL_JOIN,
+                                                         RIONET_DOORBELL_LEAVE)))
+                {
+                        printk(KERN_ERR "%s: error requesting doorbells\n",
+                               DRV_NAME);
+                        continue;
+                }
+
+                /*
+                 * If device has initialized inbound doorbells,
+                 * send a join message
+                 */
+                rio_read_config_32(peer->rdev, RIO_WRITE_PORT_CSR, &pwdcsr);
+                if (pwdcsr & RIO_DOORBELL_AVAIL)
+                        rio_send_doorbell(peer->rdev, RIONET_DOORBELL_JOIN);
+        }
+
+      out:
+        return rc;
+}
+
+static int rionet_close(struct net_device *ndev)
+{
+        struct rionet_private *rnet = (struct rionet_private *)ndev->priv;
+        struct rionet_peer *peer, *tmp;
+        int i;
+
+        if (netif_msg_ifup(rnet))
+                printk(KERN_INFO "%s: close\n", DRV_NAME);
+
+        netif_stop_queue(ndev);
+        netif_carrier_off(ndev);
+
+        for (i = 0; i < RIONET_RX_RING_SIZE; i++)
+                if (rnet->rx_skb[i])
+                        kfree_skb(rnet->rx_skb[i]);
+
+        list_for_each_entry_safe(peer, tmp, &rionet_peers, node) {
+                if (rionet_active[peer->rdev->destid]) {
+                        rio_send_doorbell(peer->rdev, RIONET_DOORBELL_LEAVE);
+                        rionet_active[peer->rdev->destid] = NULL;
+                }
+                rio_release_outb_dbell(peer->rdev, peer->res);
+        }
+
+        rio_release_inb_dbell(rnet->mport, RIONET_DOORBELL_JOIN,
+                              RIONET_DOORBELL_LEAVE);
+        rio_release_inb_mbox(rnet->mport, RIONET_MAILBOX);
+        rio_release_outb_mbox(rnet->mport, RIONET_MAILBOX);
+
+        return 0;
+}
+
+static void rionet_remove(struct rio_dev *rdev)
+{
+        struct net_device *ndev = NULL;
+        struct rionet_peer *peer, *tmp;
+
+        unregister_netdev(ndev);
+        kfree(ndev);
+
+        list_for_each_entry_safe(peer, tmp, &rionet_peers, node) {
+                list_del(&peer->node);
+                kfree(peer);
+        }
+}
+
+static void rionet_get_drvinfo(struct net_device *ndev,
+                               struct ethtool_drvinfo *info)
+{
+        struct rionet_private *rnet = ndev->priv;
+
+        strcpy(info->driver, DRV_NAME);
+        strcpy(info->version, DRV_VERSION);
+        strcpy(info->fw_version, "n/a");
+        strcpy(info->bus_info, rnet->mport->name);
+}
+
+static u32 rionet_get_msglevel(struct net_device *ndev)
+{
+        struct rionet_private *rnet = ndev->priv;
+
+        return rnet->msg_enable;
+}
+
+static void rionet_set_msglevel(struct net_device *ndev, u32 value)
+{
+        struct rionet_private *rnet = ndev->priv;
+
+        rnet->msg_enable = value;
+}
+
+static struct ethtool_ops rionet_ethtool_ops = {
+        .get_drvinfo = rionet_get_drvinfo,
+        .get_msglevel = rionet_get_msglevel,
+        .set_msglevel = rionet_set_msglevel,
+        .get_link = ethtool_op_get_link,
+};
+
+static int rionet_setup_netdev(struct rio_mport *mport)
+{
+        int rc = 0;
+        struct net_device *ndev = NULL;
+        struct rionet_private *rnet;
+        u16 device_id;
+
+        /* Allocate our net_device structure */
+        ndev = alloc_etherdev(sizeof(struct rionet_private));
+        if (ndev == NULL) {
+                printk(KERN_INFO "%s: could not allocate ethernet device.\n",
+                       DRV_NAME);
+                rc = -ENOMEM;
+                goto out;
+        }
+
+        /* Set up private area */
+        rnet = (struct rionet_private *)ndev->priv;
+        rnet->mport = mport;
+
+        /* Set the default MAC address */
+        device_id = rio_local_get_device_id(mport);
+        ndev->dev_addr[0] = 0x00;
+        ndev->dev_addr[1] = 0x01;
+        ndev->dev_addr[2] = 0x00;
+        ndev->dev_addr[3] = 0x01;
+        ndev->dev_addr[4] = device_id >> 8;
+        ndev->dev_addr[5] = device_id & 0xff;
+
+        /* Fill in the driver function table */
+        ndev->open = &rionet_open;
+        ndev->hard_start_xmit = &rionet_start_xmit;
+        ndev->stop = &rionet_close;
+        ndev->get_stats = &rionet_stats;
+        ndev->mtu = RIO_MAX_MSG_SIZE - 14;
+        ndev->features = NETIF_F_LLTX;
+        SET_ETHTOOL_OPS(ndev, &rionet_ethtool_ops);
+
+        SET_MODULE_OWNER(ndev);
+
+        spin_lock_init(&rnet->lock);
+        spin_lock_init(&rnet->tx_lock);
+
+        rnet->msg_enable = RIONET_DEFAULT_MSGLEVEL;
+
+        rc = register_netdev(ndev);
+        if (rc != 0)
+                goto out;
+
+        printk("%s: %s %s Version %s, MAC %02x:%02x:%02x:%02x:%02x:%02x\n",
+               ndev->name,
+               DRV_NAME,
+               DRV_DESC,
+               DRV_VERSION,
+               ndev->dev_addr[0], ndev->dev_addr[1], ndev->dev_addr[2],
+               ndev->dev_addr[3], ndev->dev_addr[4], ndev->dev_addr[5]);
+
+      out:
+        return rc;
+}
+
+/*
+ * XXX Make multi-net safe
+ */
+static int rionet_probe(struct rio_dev *rdev, const struct rio_device_id *id)
+{
+        int rc = -ENODEV;
+        u32 lpef, lsrc_ops, ldst_ops;
+        struct rionet_peer *peer;
+
+        /* If local device is not rionet capable, give up quickly */
+        if (!rionet_capable)
+                goto out;
+
+        /*
+         * First time through, make sure local device is rionet
+         * capable, setup netdev,  and set flags so this is skipped
+         * on later probes
+         */
+        if (!rionet_check) {
+                rio_local_read_config_32(rdev->net->hport, RIO_PEF_CAR, &lpef);
+                rio_local_read_config_32(rdev->net->hport, RIO_SRC_OPS_CAR,
+                                         &lsrc_ops);
+                rio_local_read_config_32(rdev->net->hport, RIO_DST_OPS_CAR,
+                                         &ldst_ops);
+                if (!is_rionet_capable(lpef, lsrc_ops, ldst_ops)) {
+                        printk(KERN_ERR
+                               "%s: local device is not network capable\n",
+                               DRV_NAME);
+                        rionet_check = 1;
+                        rionet_capable = 0;
+                        goto out;
+                }
+
+                rc = rionet_setup_netdev(rdev->net->hport);
+                rionet_check = 1;
+        }
+
+        /*
+         * If the remote device has mailbox/doorbell capabilities,
+         * add it to the peer list.
+         */
+        if (dev_rionet_capable(rdev)) {
+                if (!(peer = kmalloc(sizeof(struct rionet_peer), GFP_KERNEL))) {
+                        rc = -ENOMEM;
+                        goto out;
+                }
+                peer->rdev = rdev;
+                list_add_tail(&peer->node, &rionet_peers);
+        }
+
+      out:
+        return rc;
+}
+
+static struct rio_device_id rionet_id_table[] = {
+        {RIO_DEVICE(RIO_ANY_ID, RIO_ANY_ID)}
+};
+
+static struct rio_driver rionet_driver = {
+        .name = "rionet",
+        .id_table = rionet_id_table,
+        .probe = rionet_probe,
+        .remove = rionet_remove,
+};
+
+static int __init rionet_init(void)
+{
+        return rio_register_driver(&rionet_driver);
+}
+
+static void __exit rionet_exit(void)
+{
+        rio_unregister_driver(&rionet_driver);
+}
+
+module_init(rionet_init);
+module_exit(rionet_exit);