1 files changed, 575 insertions, 0 deletions

diff --git a/driver/aim-network/networking.c b/driver/aim-network/networking.c
new file mode 100644
index 0000000..2f42de4
--- /dev/null
+++ b/driver/aim-network/networking.c
@@ -0,0 +1,575 @@
+/*
+ * Networking AIM - Networking Application Interface Module for MostCore
+ *
+ * Copyright (C) 2015, Microchip Technology Germany II GmbH & Co. KG
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * This file is licensed under GPLv2.
+ */
+
+#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
+
+#include <linux/module.h>
+#include <linux/netdevice.h>
+#include <linux/etherdevice.h>
+#include <linux/slab.h>
+#include <linux/init.h>
+#include <linux/list.h>
+#include <linux/wait.h>
+#include <linux/kobject.h>
+#include "mostcore.h"
+#include "networking.h"
+
+#define MEP_HDR_LEN 8
+#define MDP_HDR_LEN 16
+#define MAMAC_DATA_LEN (1024 - MDP_HDR_LEN)
+
+#define PMHL 5
+
+#define PMS_TELID_UNSEGM_MAMAC	0x0A
+#define PMS_FIFONO_MDP		0x01
+#define PMS_FIFONO_MEP		0x04
+#define PMS_MSGTYPE_DATA	0x04
+#define PMS_DEF_PRIO		0
+#define MEP_DEF_RETRY		15
+
+#define PMS_FIFONO_MASK		0x07
+#define PMS_FIFONO_SHIFT	3
+#define PMS_RETRY_SHIFT		4
+#define PMS_TELID_MASK		0x0F
+#define PMS_TELID_SHIFT		4
+
+#define HB(value)		((u8)((u16)(value) >> 8))
+#define LB(value)		((u8)(value))
+
+#define EXTRACT_BIT_SET(bitset_name, value) \
+	(((value) >> bitset_name##_SHIFT) & bitset_name##_MASK)
+
+#define PMS_IS_MEP(buf, len) \
+	((len) > MEP_HDR_LEN && \
+	 EXTRACT_BIT_SET(PMS_FIFONO, (buf)[3]) == PMS_FIFONO_MEP)
+
+#define PMS_IS_MAMAC(buf, len) \
+	((len) > MDP_HDR_LEN && \
+	 EXTRACT_BIT_SET(PMS_FIFONO, (buf)[3]) == PMS_FIFONO_MDP && \
+	 EXTRACT_BIT_SET(PMS_TELID, (buf)[14]) == PMS_TELID_UNSEGM_MAMAC)
+
+struct net_dev_channel {
+	bool linked;
+	int ch_id;
+};
+
+struct net_dev_context {
+	struct most_interface *iface;
+	bool channels_opened;
+	bool is_mamac;
+	unsigned char link_stat;
+	struct net_device *dev;
+	struct net_dev_channel rx;
+	struct net_dev_channel tx;
+	struct list_head list;
+};
+
+static struct list_head net_devices = LIST_HEAD_INIT(net_devices);
+static struct spinlock list_lock;
+static struct most_aim aim;
+
+static int skb_to_mamac(const struct sk_buff *skb, struct mbo *mbo)
+{
+	u8 *buff = mbo->virt_address;
+	const u8 broadcast[] = { 0x03, 0xFF };
+	const u8 *dest_addr = skb->data + 4;
+	const u8 *eth_type = skb->data + 12;
+	unsigned int payload_len = skb->len - ETH_HLEN;
+	unsigned int mdp_len = payload_len + MDP_HDR_LEN;
+
+	if (mbo->buffer_length < mdp_len) {
+		pr_err("drop: too small buffer! (%d for %d)\n",
+		       mbo->buffer_length, mdp_len);
+		return -EINVAL;
+	}
+
+	if (skb->len < ETH_HLEN) {
+		pr_err("drop: too small packet! (%d)\n", skb->len);
+		return -EINVAL;
+	}
+
+	if (dest_addr[0] == 0xFF && dest_addr[1] == 0xFF)
+		dest_addr = broadcast;
+
+	*buff++ = HB(mdp_len - 2);
+	*buff++ = LB(mdp_len - 2);
+
+	*buff++ = PMHL;
+	*buff++ = (PMS_FIFONO_MDP << PMS_FIFONO_SHIFT) | PMS_MSGTYPE_DATA;
+	*buff++ = PMS_DEF_PRIO;
+	*buff++ = dest_addr[0];
+	*buff++ = dest_addr[1];
+	*buff++ = 0x00;
+
+	*buff++ = HB(payload_len + 6);
+	*buff++ = LB(payload_len + 6);
+
+	/* end of FPH here */
+
+	*buff++ = eth_type[0];
+	*buff++ = eth_type[1];
+	*buff++ = 0;
+	*buff++ = 0;
+
+	*buff++ = PMS_TELID_UNSEGM_MAMAC << 4 | HB(payload_len);
+	*buff++ = LB(payload_len);
+
+	memcpy(buff, skb->data + ETH_HLEN, payload_len);
+	mbo->buffer_length = mdp_len;
+	return 0;
+}
+
+static int skb_to_mep(const struct sk_buff *skb, struct mbo *mbo)
+{
+	u8 *buff = mbo->virt_address;
+	unsigned int mep_len = skb->len + MEP_HDR_LEN;
+
+	if (mbo->buffer_length < mep_len) {
+		pr_err("drop: too small buffer! (%d for %d)\n",
+		       mbo->buffer_length, mep_len);
+		return -EINVAL;
+	}
+
+	*buff++ = HB(mep_len - 2);
+	*buff++ = LB(mep_len - 2);
+
+	*buff++ = PMHL;
+	*buff++ = (PMS_FIFONO_MEP << PMS_FIFONO_SHIFT) | PMS_MSGTYPE_DATA;
+	*buff++ = (MEP_DEF_RETRY << PMS_RETRY_SHIFT) | PMS_DEF_PRIO;
+	*buff++ = 0;
+	*buff++ = 0;
+	*buff++ = 0;
+
+	memcpy(buff, skb->data, skb->len);
+	mbo->buffer_length = mep_len;
+	return 0;
+}
+
+static int most_nd_set_mac_address(struct net_device *dev, void *p)
+{
+	struct net_dev_context *nd = dev->ml_priv;
+	int err = eth_mac_addr(dev, p);
+
+	if (err)
+		return err;
+
+	BUG_ON(nd->dev != dev);
+
+	nd->is_mamac =
+		(dev->dev_addr[0] == 0 && dev->dev_addr[1] == 0 &&
+		 dev->dev_addr[2] == 0 && dev->dev_addr[3] == 0);
+
+	/*
+	 * Set default MTU for the given packet type.
+	 * It is still possible to change MTU using ip tools afterwards.
+	 */
+	dev->mtu = nd->is_mamac ? MAMAC_DATA_LEN : ETH_DATA_LEN;
+
+	return 0;
+}
+
+static int most_nd_open(struct net_device *dev)
+{
+	struct net_dev_context *nd = dev->ml_priv;
+
+	netdev_info(dev, "open net device\n");
+
+	BUG_ON(nd->dev != dev);
+
+	if (nd->channels_opened)
+		return -EFAULT;
+
+	BUG_ON(!nd->tx.linked || !nd->rx.linked);
+
+	if (most_start_channel(nd->iface, nd->rx.ch_id, &aim)) {
+		netdev_err(dev, "most_start_channel() failed\n");
+		return -EBUSY;
+	}
+
+	if (most_start_channel(nd->iface, nd->tx.ch_id, &aim)) {
+		netdev_err(dev, "most_start_channel() failed\n");
+		most_stop_channel(nd->iface, nd->rx.ch_id, &aim);
+		return -EBUSY;
+	}
+
+	nd->channels_opened = true;
+
+	if (nd->is_mamac) {
+		nd->link_stat = 1;
+		netif_wake_queue(dev);
+	} else {
+		nd->iface->request_netinfo(nd->iface, nd->tx.ch_id);
+	}
+
+	return 0;
+}
+
+static int most_nd_stop(struct net_device *dev)
+{
+	struct net_dev_context *nd = dev->ml_priv;
+
+	netdev_info(dev, "stop net device\n");
+
+	BUG_ON(nd->dev != dev);
+	netif_stop_queue(dev);
+
+	if (nd->channels_opened) {
+		most_stop_channel(nd->iface, nd->rx.ch_id, &aim);
+		most_stop_channel(nd->iface, nd->tx.ch_id, &aim);
+		nd->channels_opened = false;
+	}
+
+	return 0;
+}
+
+static netdev_tx_t most_nd_start_xmit(struct sk_buff *skb,
+				      struct net_device *dev)
+{
+	struct net_dev_context *nd = dev->ml_priv;
+	struct mbo *mbo;
+	int ret;
+
+	BUG_ON(nd->dev != dev);
+
+	mbo = most_get_mbo(nd->iface, nd->tx.ch_id, &aim);
+
+	if (!mbo) {
+		netif_stop_queue(dev);
+		dev->stats.tx_fifo_errors++;
+		return NETDEV_TX_BUSY;
+	}
+
+	if (nd->is_mamac)
+		ret = skb_to_mamac(skb, mbo);
+	else
+		ret = skb_to_mep(skb, mbo);
+
+	if (ret) {
+		most_put_mbo(mbo);
+		dev->stats.tx_dropped++;
+		kfree_skb(skb);
+		return NETDEV_TX_OK;
+	}
+
+	most_submit_mbo(mbo);
+	dev->stats.tx_packets++;
+	dev->stats.tx_bytes += skb->len;
+	kfree_skb(skb);
+	return NETDEV_TX_OK;
+}
+
+static const struct net_device_ops most_nd_ops = {
+	.ndo_open = most_nd_open,
+	.ndo_stop = most_nd_stop,
+	.ndo_start_xmit = most_nd_start_xmit,
+	.ndo_set_mac_address = most_nd_set_mac_address,
+};
+
+static void most_nd_setup(struct net_device *dev)
+{
+	netdev_info(dev, "setup net device\n");
+	ether_setup(dev);
+	dev->netdev_ops = &most_nd_ops;
+}
+
+static void most_net_rm_netdev_safe(struct net_dev_context *nd)
+{
+	if (!nd->dev)
+		return;
+
+	pr_info("remove net device %p\n", nd->dev);
+
+	unregister_netdev(nd->dev);
+	free_netdev(nd->dev);
+	nd->dev = NULL;
+}
+
+static struct net_dev_context *get_net_dev_context(
+	struct most_interface *iface)
+{
+	struct net_dev_context *nd, *tmp;
+
+	spin_lock(&list_lock);
+	list_for_each_entry_safe(nd, tmp, &net_devices, list) {
+		if (nd->iface == iface) {
+			spin_unlock(&list_lock);
+			return nd;
+		}
+	}
+	spin_unlock(&list_lock);
+	return NULL;
+}
+
+static int aim_probe_channel(struct most_interface *iface, int channel_idx,
+			     struct most_channel_config *ccfg,
+			     struct kobject *parent, char *name)
+{
+	struct net_dev_context *nd;
+	struct net_dev_channel *ch;
+
+	if (!iface)
+		return -EINVAL;
+
+	if (ccfg->data_type != MOST_CH_ASYNC)
+		return -EINVAL;
+
+	nd = get_net_dev_context(iface);
+
+	if (!nd) {
+		nd = kzalloc(sizeof(*nd), GFP_KERNEL);
+		if (!nd)
+			return -ENOMEM;
+
+		nd->iface = iface;
+
+		spin_lock(&list_lock);
+		list_add(&nd->list, &net_devices);
+		spin_unlock(&list_lock);
+	}
+
+	ch = ccfg->direction == MOST_CH_TX ? &nd->tx : &nd->rx;
+	if (ch->linked) {
+		pr_err("only one channel per instance & direction allowed\n");
+		return -EINVAL;
+	}
+
+	if (nd->tx.linked || nd->rx.linked) {
+		struct net_device *dev =
+			alloc_netdev(0, "meth%d", NET_NAME_UNKNOWN,
+				     most_nd_setup);
+
+		if (!dev) {
+			pr_err("no memory for net_device\n");
+			return -ENOMEM;
+		}
+
+		nd->dev = dev;
+		ch->ch_id = channel_idx;
+		ch->linked = true;
+
+		dev->ml_priv = nd;
+		if (register_netdev(dev)) {
+			pr_err("registering net device failed\n");
+			ch->linked = false;
+			free_netdev(dev);
+			return -EINVAL;
+		}
+	}
+
+	ch->ch_id = channel_idx;
+	ch->linked = true;
+
+	return 0;
+}
+
+static int aim_disconnect_channel(struct most_interface *iface,
+				  int channel_idx)
+{
+	struct net_dev_context *nd;
+	struct net_dev_channel *ch;
+
+	nd = get_net_dev_context(iface);
+	if (!nd)
+		return -EINVAL;
+
+	if (nd->rx.linked && channel_idx == nd->rx.ch_id)
+		ch = &nd->rx;
+	else if (nd->tx.linked && channel_idx == nd->tx.ch_id)
+		ch = &nd->tx;
+	else
+		return -EINVAL;
+
+	ch->linked = false;
+
+	/*
+	 * do not call most_stop_channel() here, because channels are
+	 * going to be closed in ndo_stop() after unregister_netdev()
+	 */
+	most_net_rm_netdev_safe(nd);
+
+	if (!nd->rx.linked && !nd->tx.linked) {
+		spin_lock(&list_lock);
+		list_del(&nd->list);
+		spin_unlock(&list_lock);
+		kfree(nd);
+	}
+
+	return 0;
+}
+
+static int aim_resume_tx_channel(struct most_interface *iface,
+				 int channel_idx)
+{
+	struct net_dev_context *nd;
+
+	nd = get_net_dev_context(iface);
+	if (!nd || !nd->channels_opened || nd->tx.ch_id != channel_idx)
+		return 0;
+
+	if (!nd->dev)
+		return 0;
+
+	netif_wake_queue(nd->dev);
+	return 0;
+}
+
+static int aim_rx_data(struct mbo *mbo)
+{
+	const u32 zero = 0;
+	struct net_dev_context *nd;
+	char *buf = mbo->virt_address;
+	u32 len = mbo->processed_length;
+	struct sk_buff *skb;
+	struct net_device *dev;
+	unsigned int skb_len;
+
+	nd = get_net_dev_context(mbo->ifp);
+	if (!nd || !nd->channels_opened || nd->rx.ch_id != mbo->hdm_channel_id)
+		return -EIO;
+
+	dev = nd->dev;
+	if (!dev) {
+		pr_err_once("drop packet: missing net_device\n");
+		return -EIO;
+	}
+
+	if (nd->is_mamac) {
+		if (!PMS_IS_MAMAC(buf, len))
+			return -EIO;
+
+		skb = dev_alloc_skb(len - MDP_HDR_LEN + 2 * ETH_ALEN + 2);
+	} else {
+		if (!PMS_IS_MEP(buf, len))
+			return -EIO;
+
+		skb = dev_alloc_skb(len - MEP_HDR_LEN);
+	}
+
+	if (!skb) {
+		dev->stats.rx_dropped++;
+		pr_err_once("drop packet: no memory for skb\n");
+		goto out;
+	}
+
+	skb->dev = dev;
+
+	if (nd->is_mamac) {
+		/* dest */
+		ether_addr_copy(skb_put(skb, ETH_ALEN), dev->dev_addr);
+
+		/* src */
+		memcpy(skb_put(skb, 4), &zero, 4);
+		memcpy(skb_put(skb, 2), buf + 5, 2);
+
+		/* eth type */
+		memcpy(skb_put(skb, 2), buf + 10, 2);
+
+		buf += MDP_HDR_LEN;
+		len -= MDP_HDR_LEN;
+	} else {
+		buf += MEP_HDR_LEN;
+		len -= MEP_HDR_LEN;
+	}
+
+	memcpy(skb_put(skb, len), buf, len);
+	skb->protocol = eth_type_trans(skb, dev);
+	skb_len = skb->len;
+	if (netif_rx(skb) == NET_RX_SUCCESS) {
+		dev->stats.rx_packets++;
+		dev->stats.rx_bytes += skb_len;
+	} else {
+		dev->stats.rx_dropped++;
+	}
+
+out:
+	most_put_mbo(mbo);
+	return 0;
+}
+
+static struct most_aim aim = {
+	.name = "networking",
+	.probe_channel = aim_probe_channel,
+	.disconnect_channel = aim_disconnect_channel,
+	.tx_completion = aim_resume_tx_channel,
+	.rx_completion = aim_rx_data,
+};
+
+static int __init most_net_init(void)
+{
+	pr_info("most_net_init()\n");
+	spin_lock_init(&list_lock);
+	return most_register_aim(&aim);
+}
+
+static void __exit most_net_exit(void)
+{
+	struct net_dev_context *nd, *tmp;
+
+	spin_lock(&list_lock);
+	list_for_each_entry_safe(nd, tmp, &net_devices, list) {
+		list_del(&nd->list);
+		spin_unlock(&list_lock);
+		/*
+		 * do not call most_stop_channel() here, because channels are
+		 * going to be closed in ndo_stop() after unregister_netdev()
+		 */
+		most_net_rm_netdev_safe(nd);
+		kfree(nd);
+		spin_lock(&list_lock);
+	}
+	spin_unlock(&list_lock);
+
+	most_deregister_aim(&aim);
+	pr_info("most_net_exit()\n");
+}
+
+/**
+ * most_deliver_netinfo - callback for HDM to be informed about HW's MAC
+ * @param iface - most interface instance
+ * @param link_stat - link status
+ * @param mac_addr - MAC address
+ */
+void most_deliver_netinfo(struct most_interface *iface,
+			  unsigned char link_stat, unsigned char *mac_addr)
+{
+	struct net_dev_context *nd;
+	struct net_device *dev;
+
+	pr_info("Received netinfo from %s\n", iface->description);
+
+	nd = get_net_dev_context(iface);
+	if (!nd)
+		return;
+
+	dev = nd->dev;
+	if (!dev)
+		return;
+
+	if (mac_addr)
+		ether_addr_copy(dev->dev_addr, mac_addr);
+
+	if (nd->link_stat != link_stat) {
+		nd->link_stat = link_stat;
+		if (nd->link_stat)
+			netif_wake_queue(dev);
+		else
+			netif_stop_queue(dev);
+	}
+}
+EXPORT_SYMBOL(most_deliver_netinfo);
+
+module_init(most_net_init);
+module_exit(most_net_exit);
+MODULE_LICENSE("GPL");
+MODULE_AUTHOR("Andrey Shvetsov <andrey.shvetsov@k2l.de>");
+MODULE_DESCRIPTION("Networking Application Interface Module for MostCore");