These changes are the raw update to linux-4.4.6-rt14. Kernel sources
[kvmfornfv.git] / kernel / drivers / staging / most / aim-network / networking.c
diff --git a/kernel/drivers/staging/most/aim-network/networking.c b/kernel/drivers/staging/most/aim-network/networking.c
new file mode 100644 (file)
index 0000000..3c7beb0
--- /dev/null
@@ -0,0 +1,570 @@
+/*
+ * 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;
+
+       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);
+       dev->stats.rx_packets++;
+       dev->stats.rx_bytes += skb->len;
+       netif_rx(skb);
+
+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");