diff options
Diffstat (limited to 'drivers/net/mhi/net.c')
-rw-r--r-- | drivers/net/mhi/net.c | 486 |
1 files changed, 0 insertions, 486 deletions
diff --git a/drivers/net/mhi/net.c b/drivers/net/mhi/net.c deleted file mode 100644 index e60e38c1f09d..000000000000 --- a/drivers/net/mhi/net.c +++ /dev/null @@ -1,486 +0,0 @@ -// SPDX-License-Identifier: GPL-2.0-or-later -/* MHI Network driver - Network over MHI bus - * - * Copyright (C) 2020 Linaro Ltd <loic.poulain@linaro.org> - */ - -#include <linux/if_arp.h> -#include <linux/mhi.h> -#include <linux/mod_devicetable.h> -#include <linux/module.h> -#include <linux/netdevice.h> -#include <linux/skbuff.h> -#include <linux/u64_stats_sync.h> -#include <linux/wwan.h> - -#include "mhi.h" - -#define MHI_NET_MIN_MTU ETH_MIN_MTU -#define MHI_NET_MAX_MTU 0xffff -#define MHI_NET_DEFAULT_MTU 0x4000 - -/* When set to false, the default netdev (link 0) is not created, and it's up - * to user to create the link (via wwan rtnetlink). - */ -static bool create_default_iface = true; -module_param(create_default_iface, bool, 0); - -struct mhi_device_info { - const char *netname; - const struct mhi_net_proto *proto; -}; - -static int mhi_ndo_open(struct net_device *ndev) -{ - struct mhi_net_dev *mhi_netdev = wwan_netdev_drvpriv(ndev); - - /* Feed the rx buffer pool */ - schedule_delayed_work(&mhi_netdev->rx_refill, 0); - - /* Carrier is established via out-of-band channel (e.g. qmi) */ - netif_carrier_on(ndev); - - netif_start_queue(ndev); - - return 0; -} - -static int mhi_ndo_stop(struct net_device *ndev) -{ - struct mhi_net_dev *mhi_netdev = wwan_netdev_drvpriv(ndev); - - netif_stop_queue(ndev); - netif_carrier_off(ndev); - cancel_delayed_work_sync(&mhi_netdev->rx_refill); - - return 0; -} - -static netdev_tx_t mhi_ndo_xmit(struct sk_buff *skb, struct net_device *ndev) -{ - struct mhi_net_dev *mhi_netdev = wwan_netdev_drvpriv(ndev); - const struct mhi_net_proto *proto = mhi_netdev->proto; - struct mhi_device *mdev = mhi_netdev->mdev; - int err; - - if (proto && proto->tx_fixup) { - skb = proto->tx_fixup(mhi_netdev, skb); - if (unlikely(!skb)) - goto exit_drop; - } - - err = mhi_queue_skb(mdev, DMA_TO_DEVICE, skb, skb->len, MHI_EOT); - if (unlikely(err)) { - net_err_ratelimited("%s: Failed to queue TX buf (%d)\n", - ndev->name, err); - dev_kfree_skb_any(skb); - goto exit_drop; - } - - if (mhi_queue_is_full(mdev, DMA_TO_DEVICE)) - netif_stop_queue(ndev); - - return NETDEV_TX_OK; - -exit_drop: - u64_stats_update_begin(&mhi_netdev->stats.tx_syncp); - u64_stats_inc(&mhi_netdev->stats.tx_dropped); - u64_stats_update_end(&mhi_netdev->stats.tx_syncp); - - return NETDEV_TX_OK; -} - -static void mhi_ndo_get_stats64(struct net_device *ndev, - struct rtnl_link_stats64 *stats) -{ - struct mhi_net_dev *mhi_netdev = wwan_netdev_drvpriv(ndev); - unsigned int start; - - do { - start = u64_stats_fetch_begin_irq(&mhi_netdev->stats.rx_syncp); - stats->rx_packets = u64_stats_read(&mhi_netdev->stats.rx_packets); - stats->rx_bytes = u64_stats_read(&mhi_netdev->stats.rx_bytes); - stats->rx_errors = u64_stats_read(&mhi_netdev->stats.rx_errors); - stats->rx_dropped = u64_stats_read(&mhi_netdev->stats.rx_dropped); - stats->rx_length_errors = u64_stats_read(&mhi_netdev->stats.rx_length_errors); - } while (u64_stats_fetch_retry_irq(&mhi_netdev->stats.rx_syncp, start)); - - do { - start = u64_stats_fetch_begin_irq(&mhi_netdev->stats.tx_syncp); - stats->tx_packets = u64_stats_read(&mhi_netdev->stats.tx_packets); - stats->tx_bytes = u64_stats_read(&mhi_netdev->stats.tx_bytes); - stats->tx_errors = u64_stats_read(&mhi_netdev->stats.tx_errors); - stats->tx_dropped = u64_stats_read(&mhi_netdev->stats.tx_dropped); - } while (u64_stats_fetch_retry_irq(&mhi_netdev->stats.tx_syncp, start)); -} - -static const struct net_device_ops mhi_netdev_ops = { - .ndo_open = mhi_ndo_open, - .ndo_stop = mhi_ndo_stop, - .ndo_start_xmit = mhi_ndo_xmit, - .ndo_get_stats64 = mhi_ndo_get_stats64, -}; - -static void mhi_net_setup(struct net_device *ndev) -{ - ndev->header_ops = NULL; /* No header */ - ndev->type = ARPHRD_RAWIP; - ndev->hard_header_len = 0; - ndev->addr_len = 0; - ndev->flags = IFF_POINTOPOINT | IFF_NOARP; - ndev->netdev_ops = &mhi_netdev_ops; - ndev->mtu = MHI_NET_DEFAULT_MTU; - ndev->min_mtu = MHI_NET_MIN_MTU; - ndev->max_mtu = MHI_NET_MAX_MTU; - ndev->tx_queue_len = 1000; -} - -static struct sk_buff *mhi_net_skb_agg(struct mhi_net_dev *mhi_netdev, - struct sk_buff *skb) -{ - struct sk_buff *head = mhi_netdev->skbagg_head; - struct sk_buff *tail = mhi_netdev->skbagg_tail; - - /* This is non-paged skb chaining using frag_list */ - if (!head) { - mhi_netdev->skbagg_head = skb; - return skb; - } - - if (!skb_shinfo(head)->frag_list) - skb_shinfo(head)->frag_list = skb; - else - tail->next = skb; - - head->len += skb->len; - head->data_len += skb->len; - head->truesize += skb->truesize; - - mhi_netdev->skbagg_tail = skb; - - return mhi_netdev->skbagg_head; -} - -static void mhi_net_dl_callback(struct mhi_device *mhi_dev, - struct mhi_result *mhi_res) -{ - struct mhi_net_dev *mhi_netdev = dev_get_drvdata(&mhi_dev->dev); - const struct mhi_net_proto *proto = mhi_netdev->proto; - struct sk_buff *skb = mhi_res->buf_addr; - int free_desc_count; - - free_desc_count = mhi_get_free_desc_count(mhi_dev, DMA_FROM_DEVICE); - - if (unlikely(mhi_res->transaction_status)) { - switch (mhi_res->transaction_status) { - case -EOVERFLOW: - /* Packet can not fit in one MHI buffer and has been - * split over multiple MHI transfers, do re-aggregation. - * That usually means the device side MTU is larger than - * the host side MTU/MRU. Since this is not optimal, - * print a warning (once). - */ - netdev_warn_once(mhi_netdev->ndev, - "Fragmented packets received, fix MTU?\n"); - skb_put(skb, mhi_res->bytes_xferd); - mhi_net_skb_agg(mhi_netdev, skb); - break; - case -ENOTCONN: - /* MHI layer stopping/resetting the DL channel */ - dev_kfree_skb_any(skb); - return; - default: - /* Unknown error, simply drop */ - dev_kfree_skb_any(skb); - u64_stats_update_begin(&mhi_netdev->stats.rx_syncp); - u64_stats_inc(&mhi_netdev->stats.rx_errors); - u64_stats_update_end(&mhi_netdev->stats.rx_syncp); - } - } else { - skb_put(skb, mhi_res->bytes_xferd); - - if (mhi_netdev->skbagg_head) { - /* Aggregate the final fragment */ - skb = mhi_net_skb_agg(mhi_netdev, skb); - mhi_netdev->skbagg_head = NULL; - } - - u64_stats_update_begin(&mhi_netdev->stats.rx_syncp); - u64_stats_inc(&mhi_netdev->stats.rx_packets); - u64_stats_add(&mhi_netdev->stats.rx_bytes, skb->len); - u64_stats_update_end(&mhi_netdev->stats.rx_syncp); - - switch (skb->data[0] & 0xf0) { - case 0x40: - skb->protocol = htons(ETH_P_IP); - break; - case 0x60: - skb->protocol = htons(ETH_P_IPV6); - break; - default: - skb->protocol = htons(ETH_P_MAP); - break; - } - - if (proto && proto->rx) - proto->rx(mhi_netdev, skb); - else - netif_rx(skb); - } - - /* Refill if RX buffers queue becomes low */ - if (free_desc_count >= mhi_netdev->rx_queue_sz / 2) - schedule_delayed_work(&mhi_netdev->rx_refill, 0); -} - -static void mhi_net_ul_callback(struct mhi_device *mhi_dev, - struct mhi_result *mhi_res) -{ - struct mhi_net_dev *mhi_netdev = dev_get_drvdata(&mhi_dev->dev); - struct net_device *ndev = mhi_netdev->ndev; - struct mhi_device *mdev = mhi_netdev->mdev; - struct sk_buff *skb = mhi_res->buf_addr; - - /* Hardware has consumed the buffer, so free the skb (which is not - * freed by the MHI stack) and perform accounting. - */ - dev_consume_skb_any(skb); - - u64_stats_update_begin(&mhi_netdev->stats.tx_syncp); - if (unlikely(mhi_res->transaction_status)) { - - /* MHI layer stopping/resetting the UL channel */ - if (mhi_res->transaction_status == -ENOTCONN) { - u64_stats_update_end(&mhi_netdev->stats.tx_syncp); - return; - } - - u64_stats_inc(&mhi_netdev->stats.tx_errors); - } else { - u64_stats_inc(&mhi_netdev->stats.tx_packets); - u64_stats_add(&mhi_netdev->stats.tx_bytes, mhi_res->bytes_xferd); - } - u64_stats_update_end(&mhi_netdev->stats.tx_syncp); - - if (netif_queue_stopped(ndev) && !mhi_queue_is_full(mdev, DMA_TO_DEVICE)) - netif_wake_queue(ndev); -} - -static void mhi_net_rx_refill_work(struct work_struct *work) -{ - struct mhi_net_dev *mhi_netdev = container_of(work, struct mhi_net_dev, - rx_refill.work); - struct net_device *ndev = mhi_netdev->ndev; - struct mhi_device *mdev = mhi_netdev->mdev; - struct sk_buff *skb; - unsigned int size; - int err; - - size = mhi_netdev->mru ? mhi_netdev->mru : READ_ONCE(ndev->mtu); - - while (!mhi_queue_is_full(mdev, DMA_FROM_DEVICE)) { - skb = netdev_alloc_skb(ndev, size); - if (unlikely(!skb)) - break; - - err = mhi_queue_skb(mdev, DMA_FROM_DEVICE, skb, size, MHI_EOT); - if (unlikely(err)) { - net_err_ratelimited("%s: Failed to queue RX buf (%d)\n", - ndev->name, err); - kfree_skb(skb); - break; - } - - /* Do not hog the CPU if rx buffers are consumed faster than - * queued (unlikely). - */ - cond_resched(); - } - - /* If we're still starved of rx buffers, reschedule later */ - if (mhi_get_free_desc_count(mdev, DMA_FROM_DEVICE) == mhi_netdev->rx_queue_sz) - schedule_delayed_work(&mhi_netdev->rx_refill, HZ / 2); -} - -static int mhi_net_newlink(void *ctxt, struct net_device *ndev, u32 if_id, - struct netlink_ext_ack *extack) -{ - const struct mhi_device_info *info; - struct mhi_device *mhi_dev = ctxt; - struct mhi_net_dev *mhi_netdev; - int err; - - info = (struct mhi_device_info *)mhi_dev->id->driver_data; - - /* For now we only support one link (link context 0), driver must be - * reworked to break 1:1 relationship for net MBIM and to forward setup - * call to rmnet(QMAP) otherwise. - */ - if (if_id != 0) - return -EINVAL; - - if (dev_get_drvdata(&mhi_dev->dev)) - return -EBUSY; - - mhi_netdev = wwan_netdev_drvpriv(ndev); - - dev_set_drvdata(&mhi_dev->dev, mhi_netdev); - mhi_netdev->ndev = ndev; - mhi_netdev->mdev = mhi_dev; - mhi_netdev->skbagg_head = NULL; - mhi_netdev->proto = info->proto; - - INIT_DELAYED_WORK(&mhi_netdev->rx_refill, mhi_net_rx_refill_work); - u64_stats_init(&mhi_netdev->stats.rx_syncp); - u64_stats_init(&mhi_netdev->stats.tx_syncp); - - /* Start MHI channels */ - err = mhi_prepare_for_transfer(mhi_dev); - if (err) - goto out_err; - - /* Number of transfer descriptors determines size of the queue */ - mhi_netdev->rx_queue_sz = mhi_get_free_desc_count(mhi_dev, DMA_FROM_DEVICE); - - if (extack) - err = register_netdevice(ndev); - else - err = register_netdev(ndev); - if (err) - goto out_err; - - if (mhi_netdev->proto) { - err = mhi_netdev->proto->init(mhi_netdev); - if (err) - goto out_err_proto; - } - - return 0; - -out_err_proto: - unregister_netdevice(ndev); -out_err: - free_netdev(ndev); - return err; -} - -static void mhi_net_dellink(void *ctxt, struct net_device *ndev, - struct list_head *head) -{ - struct mhi_net_dev *mhi_netdev = wwan_netdev_drvpriv(ndev); - struct mhi_device *mhi_dev = ctxt; - - if (head) - unregister_netdevice_queue(ndev, head); - else - unregister_netdev(ndev); - - mhi_unprepare_from_transfer(mhi_dev); - - kfree_skb(mhi_netdev->skbagg_head); - - dev_set_drvdata(&mhi_dev->dev, NULL); -} - -static const struct wwan_ops mhi_wwan_ops = { - .priv_size = sizeof(struct mhi_net_dev), - .setup = mhi_net_setup, - .newlink = mhi_net_newlink, - .dellink = mhi_net_dellink, -}; - -static int mhi_net_probe(struct mhi_device *mhi_dev, - const struct mhi_device_id *id) -{ - const struct mhi_device_info *info = (struct mhi_device_info *)id->driver_data; - struct mhi_controller *cntrl = mhi_dev->mhi_cntrl; - struct net_device *ndev; - int err; - - err = wwan_register_ops(&cntrl->mhi_dev->dev, &mhi_wwan_ops, mhi_dev, - WWAN_NO_DEFAULT_LINK); - if (err) - return err; - - if (!create_default_iface) - return 0; - - /* Create a default interface which is used as either RMNET real-dev, - * MBIM link 0 or ip link 0) - */ - ndev = alloc_netdev(sizeof(struct mhi_net_dev), info->netname, - NET_NAME_PREDICTABLE, mhi_net_setup); - if (!ndev) { - err = -ENOMEM; - goto err_unregister; - } - - SET_NETDEV_DEV(ndev, &mhi_dev->dev); - - err = mhi_net_newlink(mhi_dev, ndev, 0, NULL); - if (err) - goto err_release; - - return 0; - -err_release: - free_netdev(ndev); -err_unregister: - wwan_unregister_ops(&cntrl->mhi_dev->dev); - - return err; -} - -static void mhi_net_remove(struct mhi_device *mhi_dev) -{ - struct mhi_net_dev *mhi_netdev = dev_get_drvdata(&mhi_dev->dev); - struct mhi_controller *cntrl = mhi_dev->mhi_cntrl; - - /* WWAN core takes care of removing remaining links */ - wwan_unregister_ops(&cntrl->mhi_dev->dev); - - if (create_default_iface) - mhi_net_dellink(mhi_dev, mhi_netdev->ndev, NULL); -} - -static const struct mhi_device_info mhi_hwip0 = { - .netname = "mhi_hwip%d", -}; - -static const struct mhi_device_info mhi_swip0 = { - .netname = "mhi_swip%d", -}; - -static const struct mhi_device_info mhi_hwip0_mbim = { - .netname = "mhi_mbim%d", - .proto = &proto_mbim, -}; - -static const struct mhi_device_id mhi_net_id_table[] = { - /* Hardware accelerated data PATH (to modem IPA), protocol agnostic */ - { .chan = "IP_HW0", .driver_data = (kernel_ulong_t)&mhi_hwip0 }, - /* Software data PATH (to modem CPU) */ - { .chan = "IP_SW0", .driver_data = (kernel_ulong_t)&mhi_swip0 }, - /* Hardware accelerated data PATH (to modem IPA), MBIM protocol */ - { .chan = "IP_HW0_MBIM", .driver_data = (kernel_ulong_t)&mhi_hwip0_mbim }, - {} -}; -MODULE_DEVICE_TABLE(mhi, mhi_net_id_table); - -static struct mhi_driver mhi_net_driver = { - .probe = mhi_net_probe, - .remove = mhi_net_remove, - .dl_xfer_cb = mhi_net_dl_callback, - .ul_xfer_cb = mhi_net_ul_callback, - .id_table = mhi_net_id_table, - .driver = { - .name = "mhi_net", - .owner = THIS_MODULE, - }, -}; - -module_mhi_driver(mhi_net_driver); - -MODULE_AUTHOR("Loic Poulain <loic.poulain@linaro.org>"); -MODULE_DESCRIPTION("Network over MHI"); -MODULE_LICENSE("GPL v2"); |