From patchwork Tue Aug 3 13:36:29 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Patchwork-Submitter: Loic Poulain X-Patchwork-Id: 12416377 X-Patchwork-Delegate: kuba@kernel.org Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-18.8 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER, INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,USER_AGENT_GIT autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 64503C4338F for ; Tue, 3 Aug 2021 13:26:25 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 3BC8A60724 for ; Tue, 3 Aug 2021 13:26:25 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S236366AbhHCN0e (ORCPT ); Tue, 3 Aug 2021 09:26:34 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:42700 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S236346AbhHCN0c (ORCPT ); Tue, 3 Aug 2021 09:26:32 -0400 Received: from mail-wr1-x431.google.com (mail-wr1-x431.google.com [IPv6:2a00:1450:4864:20::431]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 607D9C06175F for ; Tue, 3 Aug 2021 06:26:21 -0700 (PDT) Received: by mail-wr1-x431.google.com with SMTP id h14so25294757wrx.10 for ; Tue, 03 Aug 2021 06:26:21 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linaro.org; s=google; h=from:to:cc:subject:date:message-id:in-reply-to:references :mime-version:content-transfer-encoding; bh=+t8mCwkoQ8AKzK7up8IOQv7p8nVabEC9eDM4D3wPXrQ=; b=WMSSfimqUKqaOBk2S6WHdouY3q6GgkQO8eXVQ2C00ephPVYRFZqTnb2hQkywS00s19 FggrQ9+9ZFnD+FtMmT8eSMfi0knW/jivswS3uklntyKkifLeylA26/xeASX584U2udE/ XR+oZ0DC5fw7+Pw3ogyVBswMjbp2QyJbqQUqTfu8lwn59To/nPru28jvK+FGe2GuZcgd Bro6qcSCj3Z0jso2fRjYFwDktGUFSdSRXykRp0ZdHqIOvHzdhz3LcscdmpemA6roF6LE K90P/L6KtVypjAVOcLNEBKCJOR+QdtWOTgU84y2uoCYBVB5/5NzEvNthOmnj+sBMwrLn shAQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:from:to:cc:subject:date:message-id:in-reply-to :references:mime-version:content-transfer-encoding; bh=+t8mCwkoQ8AKzK7up8IOQv7p8nVabEC9eDM4D3wPXrQ=; b=VWjXrm6fv14WQbYRueZd5yrw9Jc4YEpvY1z6ThUqgSBToWbYk65ljU5nEpLIYT6TSt tnBWdZ5mNAju6Onmf1eIQ7fpX7Z8bwC71V2DMHhTJ43BX7n/8eCxWxDsnoWKpAVTW6B2 oTWNe3OdwiBMXKSIbqrsw9ZLO4+GAIutTI/WX+kAZEGYrSMLRLj48q9WfXDLVj9j8pZL a+9pKd+kHpJSO8coYlC3vPvdQmja54nP0ZfRH7Z1dhGwN6LAdjO1v6iGDJXjMXWN3mHA GZJ0BfoxFVVbPfsCkV6+smRw+ThVKdVRKanV+fvsSmTz5emO/O2REeY3nSZ8/+It4R/d mHug== X-Gm-Message-State: AOAM5310IkGF1NYrrBQuFmsS6HrUwWeHVGgX5ev12V2yGGgQEEIbQVt6 mzOAloX5Gg6fJGeaenS3Uxhqjg== X-Google-Smtp-Source: ABdhPJy5ZgWpyULPpFXlvLNmjJdSxpCdqbP4qa0DvBPkUjVVVoy8TVS0kT/xpOsCEPcdBJRJqXgFCA== X-Received: by 2002:adf:ea52:: with SMTP id j18mr23116448wrn.294.1627997179640; Tue, 03 Aug 2021 06:26:19 -0700 (PDT) Received: from localhost.localdomain ([2a01:e0a:82c:5f0:69b5:b274:5cfc:ef2]) by smtp.gmail.com with ESMTPSA id k17sm3162065wmj.0.2021.08.03.06.26.18 (version=TLS1_2 cipher=ECDHE-ECDSA-AES128-GCM-SHA256 bits=128/128); Tue, 03 Aug 2021 06:26:18 -0700 (PDT) From: Loic Poulain To: davem@davemloft.net, kuba@kernel.org Cc: ryazanov.s.a@gmail.com, johannes@sipsolutions.net, richard.laing@alliedtelesis.co.nz, netdev@vger.kernel.org, Loic Poulain Subject: [PATCH net-next v2 2/2] net: mhi: Remove MBIM protocol Date: Tue, 3 Aug 2021 15:36:29 +0200 Message-Id: <1627997789-7323-3-git-send-email-loic.poulain@linaro.org> X-Mailer: git-send-email 2.7.4 In-Reply-To: <1627997789-7323-1-git-send-email-loic.poulain@linaro.org> References: <1627997789-7323-1-git-send-email-loic.poulain@linaro.org> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org X-Patchwork-Delegate: kuba@kernel.org The MBIM protocol has now been integrated in a proper WWAN driver. We can then revert back to a simpler driver for mhi_net, which is used for raw IP or QMAP protocol (via rmnet link). - Remove protocol management - Remove WWAN framework usage (only valid for mbim) - Remove net/mhi directory for simpler mhi_net.c file Signed-off-by: Loic Poulain --- drivers/net/Kconfig | 4 +- drivers/net/Makefile | 2 +- drivers/net/mhi/Makefile | 3 - drivers/net/mhi/mhi.h | 41 ---- drivers/net/mhi/net.c | 487 ------------------------------------------- drivers/net/mhi/proto_mbim.c | 310 --------------------------- drivers/net/mhi_net.c | 416 ++++++++++++++++++++++++++++++++++++ 7 files changed, 419 insertions(+), 844 deletions(-) delete mode 100644 drivers/net/mhi/Makefile delete mode 100644 drivers/net/mhi/mhi.h delete mode 100644 drivers/net/mhi/net.c delete mode 100644 drivers/net/mhi/proto_mbim.c create mode 100644 drivers/net/mhi_net.c diff --git a/drivers/net/Kconfig b/drivers/net/Kconfig index 6977f82..12b1a3c 100644 --- a/drivers/net/Kconfig +++ b/drivers/net/Kconfig @@ -431,10 +431,10 @@ config VSOCKMON config MHI_NET tristate "MHI network driver" depends on MHI_BUS - select WWAN help This is the network driver for MHI bus. It can be used with - QCOM based WWAN modems (like SDX55). Say Y or M. + QCOM based WWAN modems for IP or QMAP/rmnet protocol (like SDX55). + Say Y or M. endif # NET_CORE diff --git a/drivers/net/Makefile b/drivers/net/Makefile index 7ffd2d0..bfbe2a7 100644 --- a/drivers/net/Makefile +++ b/drivers/net/Makefile @@ -36,7 +36,7 @@ obj-$(CONFIG_GTP) += gtp.o obj-$(CONFIG_NLMON) += nlmon.o obj-$(CONFIG_NET_VRF) += vrf.o obj-$(CONFIG_VSOCKMON) += vsockmon.o -obj-$(CONFIG_MHI_NET) += mhi/ +obj-$(CONFIG_MHI_NET) += mhi_net.o # # Networking Drivers diff --git a/drivers/net/mhi/Makefile b/drivers/net/mhi/Makefile deleted file mode 100644 index f71b9f8..0000000 --- a/drivers/net/mhi/Makefile +++ /dev/null @@ -1,3 +0,0 @@ -obj-$(CONFIG_MHI_NET) += mhi_net.o - -mhi_net-y := net.o proto_mbim.o diff --git a/drivers/net/mhi/mhi.h b/drivers/net/mhi/mhi.h deleted file mode 100644 index 1d0c499..0000000 --- a/drivers/net/mhi/mhi.h +++ /dev/null @@ -1,41 +0,0 @@ -/* SPDX-License-Identifier: GPL-2.0-or-later */ -/* MHI Network driver - Network over MHI bus - * - * Copyright (C) 2021 Linaro Ltd - */ - -struct mhi_net_stats { - u64_stats_t rx_packets; - u64_stats_t rx_bytes; - u64_stats_t rx_errors; - u64_stats_t rx_dropped; - u64_stats_t rx_length_errors; - u64_stats_t tx_packets; - u64_stats_t tx_bytes; - u64_stats_t tx_errors; - u64_stats_t tx_dropped; - struct u64_stats_sync tx_syncp; - struct u64_stats_sync rx_syncp; -}; - -struct mhi_net_dev { - struct mhi_device *mdev; - struct net_device *ndev; - struct sk_buff *skbagg_head; - struct sk_buff *skbagg_tail; - const struct mhi_net_proto *proto; - void *proto_data; - struct delayed_work rx_refill; - struct mhi_net_stats stats; - u32 rx_queue_sz; - int msg_enable; - unsigned int mru; -}; - -struct mhi_net_proto { - int (*init)(struct mhi_net_dev *mhi_netdev); - struct sk_buff * (*tx_fixup)(struct mhi_net_dev *mhi_netdev, struct sk_buff *skb); - void (*rx)(struct mhi_net_dev *mhi_netdev, struct sk_buff *skb); -}; - -extern const struct mhi_net_proto proto_mbim; diff --git a/drivers/net/mhi/net.c b/drivers/net/mhi/net.c deleted file mode 100644 index 0cc7dcd..0000000 --- a/drivers/net/mhi/net.c +++ /dev/null @@ -1,487 +0,0 @@ -// SPDX-License-Identifier: GPL-2.0-or-later -/* MHI Network driver - Network over MHI bus - * - * Copyright (C) 2020 Linaro Ltd - */ - -#include -#include -#include -#include -#include -#include -#include -#include - -#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; - } - - 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 { - 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); - 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; - mhi_netdev->mru = mhi_dev->mhi_cntrl->mru; - - 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 "); -MODULE_DESCRIPTION("Network over MHI"); -MODULE_LICENSE("GPL v2"); diff --git a/drivers/net/mhi/proto_mbim.c b/drivers/net/mhi/proto_mbim.c deleted file mode 100644 index 761d90b..0000000 --- a/drivers/net/mhi/proto_mbim.c +++ /dev/null @@ -1,310 +0,0 @@ -// SPDX-License-Identifier: GPL-2.0-or-later -/* MHI Network driver - Network over MHI bus - * - * Copyright (C) 2021 Linaro Ltd - * - * This driver copy some code from cdc_ncm, which is: - * Copyright (C) ST-Ericsson 2010-2012 - * and cdc_mbim, which is: - * Copyright (c) 2012 Smith Micro Software, Inc. - * Copyright (c) 2012 Bjørn Mork - * - */ - -#include -#include -#include -#include -#include -#include -#include -#include -#include -#include -#include - -#include "mhi.h" - -#define MBIM_NDP16_SIGN_MASK 0x00ffffff - -/* Usual WWAN MTU */ -#define MHI_MBIM_DEFAULT_MTU 1500 - -/* 3500 allows to optimize skb allocation, the skbs will basically fit in - * one 4K page. Large MBIM packets will simply be split over several MHI - * transfers and chained by the MHI net layer (zerocopy). - */ -#define MHI_MBIM_DEFAULT_MRU 3500 - -struct mbim_context { - u16 rx_seq; - u16 tx_seq; -}; - -static void __mbim_length_errors_inc(struct mhi_net_dev *dev) -{ - u64_stats_update_begin(&dev->stats.rx_syncp); - u64_stats_inc(&dev->stats.rx_length_errors); - u64_stats_update_end(&dev->stats.rx_syncp); -} - -static void __mbim_errors_inc(struct mhi_net_dev *dev) -{ - u64_stats_update_begin(&dev->stats.rx_syncp); - u64_stats_inc(&dev->stats.rx_errors); - u64_stats_update_end(&dev->stats.rx_syncp); -} - -static int mbim_rx_verify_nth16(struct sk_buff *skb) -{ - struct mhi_net_dev *dev = wwan_netdev_drvpriv(skb->dev); - struct mbim_context *ctx = dev->proto_data; - struct usb_cdc_ncm_nth16 *nth16; - int len; - - if (skb->len < sizeof(struct usb_cdc_ncm_nth16) + - sizeof(struct usb_cdc_ncm_ndp16)) { - netif_dbg(dev, rx_err, dev->ndev, "frame too short\n"); - __mbim_length_errors_inc(dev); - return -EINVAL; - } - - nth16 = (struct usb_cdc_ncm_nth16 *)skb->data; - - if (nth16->dwSignature != cpu_to_le32(USB_CDC_NCM_NTH16_SIGN)) { - netif_dbg(dev, rx_err, dev->ndev, - "invalid NTH16 signature <%#010x>\n", - le32_to_cpu(nth16->dwSignature)); - __mbim_errors_inc(dev); - return -EINVAL; - } - - /* No limit on the block length, except the size of the data pkt */ - len = le16_to_cpu(nth16->wBlockLength); - if (len > skb->len) { - netif_dbg(dev, rx_err, dev->ndev, - "NTB does not fit into the skb %u/%u\n", len, - skb->len); - __mbim_length_errors_inc(dev); - return -EINVAL; - } - - if (ctx->rx_seq + 1 != le16_to_cpu(nth16->wSequence) && - (ctx->rx_seq || le16_to_cpu(nth16->wSequence)) && - !(ctx->rx_seq == 0xffff && !le16_to_cpu(nth16->wSequence))) { - netif_dbg(dev, rx_err, dev->ndev, - "sequence number glitch prev=%d curr=%d\n", - ctx->rx_seq, le16_to_cpu(nth16->wSequence)); - } - ctx->rx_seq = le16_to_cpu(nth16->wSequence); - - return le16_to_cpu(nth16->wNdpIndex); -} - -static int mbim_rx_verify_ndp16(struct sk_buff *skb, struct usb_cdc_ncm_ndp16 *ndp16) -{ - struct mhi_net_dev *dev = wwan_netdev_drvpriv(skb->dev); - int ret; - - if (le16_to_cpu(ndp16->wLength) < USB_CDC_NCM_NDP16_LENGTH_MIN) { - netif_dbg(dev, rx_err, dev->ndev, "invalid DPT16 length <%u>\n", - le16_to_cpu(ndp16->wLength)); - return -EINVAL; - } - - ret = ((le16_to_cpu(ndp16->wLength) - sizeof(struct usb_cdc_ncm_ndp16)) - / sizeof(struct usb_cdc_ncm_dpe16)); - ret--; /* Last entry is always a NULL terminator */ - - if (sizeof(struct usb_cdc_ncm_ndp16) + - ret * sizeof(struct usb_cdc_ncm_dpe16) > skb->len) { - netif_dbg(dev, rx_err, dev->ndev, - "Invalid nframes = %d\n", ret); - return -EINVAL; - } - - return ret; -} - -static void mbim_rx(struct mhi_net_dev *mhi_netdev, struct sk_buff *skb) -{ - struct net_device *ndev = mhi_netdev->ndev; - int ndpoffset; - - /* Check NTB header and retrieve first NDP offset */ - ndpoffset = mbim_rx_verify_nth16(skb); - if (ndpoffset < 0) { - net_err_ratelimited("%s: Incorrect NTB header\n", ndev->name); - goto error; - } - - /* Process each NDP */ - while (1) { - struct usb_cdc_ncm_ndp16 ndp16; - struct usb_cdc_ncm_dpe16 dpe16; - int nframes, n, dpeoffset; - - if (skb_copy_bits(skb, ndpoffset, &ndp16, sizeof(ndp16))) { - net_err_ratelimited("%s: Incorrect NDP offset (%u)\n", - ndev->name, ndpoffset); - __mbim_length_errors_inc(mhi_netdev); - goto error; - } - - /* Check NDP header and retrieve number of datagrams */ - nframes = mbim_rx_verify_ndp16(skb, &ndp16); - if (nframes < 0) { - net_err_ratelimited("%s: Incorrect NDP16\n", ndev->name); - __mbim_length_errors_inc(mhi_netdev); - goto error; - } - - /* Only IP data type supported, no DSS in MHI context */ - if ((ndp16.dwSignature & cpu_to_le32(MBIM_NDP16_SIGN_MASK)) - != cpu_to_le32(USB_CDC_MBIM_NDP16_IPS_SIGN)) { - net_err_ratelimited("%s: Unsupported NDP type\n", ndev->name); - __mbim_errors_inc(mhi_netdev); - goto next_ndp; - } - - /* Only primary IP session 0 (0x00) supported for now */ - if (ndp16.dwSignature & ~cpu_to_le32(MBIM_NDP16_SIGN_MASK)) { - net_err_ratelimited("%s: bad packet session\n", ndev->name); - __mbim_errors_inc(mhi_netdev); - goto next_ndp; - } - - /* de-aggregate and deliver IP packets */ - dpeoffset = ndpoffset + sizeof(struct usb_cdc_ncm_ndp16); - for (n = 0; n < nframes; n++, dpeoffset += sizeof(dpe16)) { - u16 dgram_offset, dgram_len; - struct sk_buff *skbn; - - if (skb_copy_bits(skb, dpeoffset, &dpe16, sizeof(dpe16))) - break; - - dgram_offset = le16_to_cpu(dpe16.wDatagramIndex); - dgram_len = le16_to_cpu(dpe16.wDatagramLength); - - if (!dgram_offset || !dgram_len) - break; /* null terminator */ - - skbn = netdev_alloc_skb(ndev, dgram_len); - if (!skbn) - continue; - - skb_put(skbn, dgram_len); - skb_copy_bits(skb, dgram_offset, skbn->data, dgram_len); - - switch (skbn->data[0] & 0xf0) { - case 0x40: - skbn->protocol = htons(ETH_P_IP); - break; - case 0x60: - skbn->protocol = htons(ETH_P_IPV6); - break; - default: - net_err_ratelimited("%s: unknown protocol\n", - ndev->name); - __mbim_errors_inc(mhi_netdev); - dev_kfree_skb_any(skbn); - continue; - } - - 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, skbn->len); - u64_stats_update_end(&mhi_netdev->stats.rx_syncp); - netif_rx(skbn); - } -next_ndp: - /* Other NDP to process? */ - ndpoffset = (int)le16_to_cpu(ndp16.wNextNdpIndex); - if (!ndpoffset) - break; - } - - /* free skb */ - dev_consume_skb_any(skb); - return; -error: - dev_kfree_skb_any(skb); -} - -struct mbim_tx_hdr { - struct usb_cdc_ncm_nth16 nth16; - struct usb_cdc_ncm_ndp16 ndp16; - struct usb_cdc_ncm_dpe16 dpe16[2]; -} __packed; - -static struct sk_buff *mbim_tx_fixup(struct mhi_net_dev *mhi_netdev, - struct sk_buff *skb) -{ - struct mbim_context *ctx = mhi_netdev->proto_data; - unsigned int dgram_size = skb->len; - struct usb_cdc_ncm_nth16 *nth16; - struct usb_cdc_ncm_ndp16 *ndp16; - struct mbim_tx_hdr *mbim_hdr; - - /* For now, this is a partial implementation of CDC MBIM, only one NDP - * is sent, containing the IP packet (no aggregation). - */ - - /* Ensure we have enough headroom for crafting MBIM header */ - if (skb_cow_head(skb, sizeof(struct mbim_tx_hdr))) { - dev_kfree_skb_any(skb); - return NULL; - } - - mbim_hdr = skb_push(skb, sizeof(struct mbim_tx_hdr)); - - /* Fill NTB header */ - nth16 = &mbim_hdr->nth16; - nth16->dwSignature = cpu_to_le32(USB_CDC_NCM_NTH16_SIGN); - nth16->wHeaderLength = cpu_to_le16(sizeof(struct usb_cdc_ncm_nth16)); - nth16->wSequence = cpu_to_le16(ctx->tx_seq++); - nth16->wBlockLength = cpu_to_le16(skb->len); - nth16->wNdpIndex = cpu_to_le16(sizeof(struct usb_cdc_ncm_nth16)); - - /* Fill the unique NDP */ - ndp16 = &mbim_hdr->ndp16; - ndp16->dwSignature = cpu_to_le32(USB_CDC_MBIM_NDP16_IPS_SIGN); - ndp16->wLength = cpu_to_le16(sizeof(struct usb_cdc_ncm_ndp16) - + sizeof(struct usb_cdc_ncm_dpe16) * 2); - ndp16->wNextNdpIndex = 0; - - /* Datagram follows the mbim header */ - ndp16->dpe16[0].wDatagramIndex = cpu_to_le16(sizeof(struct mbim_tx_hdr)); - ndp16->dpe16[0].wDatagramLength = cpu_to_le16(dgram_size); - - /* null termination */ - ndp16->dpe16[1].wDatagramIndex = 0; - ndp16->dpe16[1].wDatagramLength = 0; - - return skb; -} - -static int mbim_init(struct mhi_net_dev *mhi_netdev) -{ - struct net_device *ndev = mhi_netdev->ndev; - - mhi_netdev->proto_data = devm_kzalloc(&ndev->dev, - sizeof(struct mbim_context), - GFP_KERNEL); - if (!mhi_netdev->proto_data) - return -ENOMEM; - - ndev->needed_headroom = sizeof(struct mbim_tx_hdr); - ndev->mtu = MHI_MBIM_DEFAULT_MTU; - - if (!mhi_netdev->mru) - mhi_netdev->mru = MHI_MBIM_DEFAULT_MRU; - - return 0; -} - -const struct mhi_net_proto proto_mbim = { - .init = mbim_init, - .rx = mbim_rx, - .tx_fixup = mbim_tx_fixup, -}; diff --git a/drivers/net/mhi_net.c b/drivers/net/mhi_net.c new file mode 100644 index 0000000..d127eb6 --- /dev/null +++ b/drivers/net/mhi_net.c @@ -0,0 +1,416 @@ +// SPDX-License-Identifier: GPL-2.0-or-later +/* MHI Network driver - Network over MHI bus + * + * Copyright (C) 2020 Linaro Ltd + */ + +#include +#include +#include +#include +#include +#include +#include + +#define MHI_NET_MIN_MTU ETH_MIN_MTU +#define MHI_NET_MAX_MTU 0xffff +#define MHI_NET_DEFAULT_MTU 0x4000 + +struct mhi_net_stats { + u64_stats_t rx_packets; + u64_stats_t rx_bytes; + u64_stats_t rx_errors; + u64_stats_t tx_packets; + u64_stats_t tx_bytes; + u64_stats_t tx_errors; + u64_stats_t tx_dropped; + struct u64_stats_sync tx_syncp; + struct u64_stats_sync rx_syncp; +}; + +struct mhi_net_dev { + struct mhi_device *mdev; + struct net_device *ndev; + struct sk_buff *skbagg_head; + struct sk_buff *skbagg_tail; + struct delayed_work rx_refill; + struct mhi_net_stats stats; + u32 rx_queue_sz; + int msg_enable; + unsigned int mru; +}; + +struct mhi_device_info { + const char *netname; +}; + +static int mhi_ndo_open(struct net_device *ndev) +{ + struct mhi_net_dev *mhi_netdev = netdev_priv(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 = netdev_priv(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 = netdev_priv(ndev); + struct mhi_device *mdev = mhi_netdev->mdev; + int err; + + 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 = netdev_priv(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); + } 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); + 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; + } + + 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; + } + + 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); + 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(struct mhi_device *mhi_dev, struct net_device *ndev) +{ + struct mhi_net_dev *mhi_netdev; + int err; + + mhi_netdev = netdev_priv(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->mru = mhi_dev->mhi_cntrl->mru; + + 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); + + err = register_netdev(ndev); + if (err) + return err; + + return 0; + +out_err: + free_netdev(ndev); + return err; +} + +static void mhi_net_dellink(struct mhi_device *mhi_dev, struct net_device *ndev) +{ + struct mhi_net_dev *mhi_netdev = netdev_priv(ndev); + + unregister_netdev(ndev); + + mhi_unprepare_from_transfer(mhi_dev); + + kfree_skb(mhi_netdev->skbagg_head); + + dev_set_drvdata(&mhi_dev->dev, NULL); +} + +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 net_device *ndev; + int err; + + ndev = alloc_netdev(sizeof(struct mhi_net_dev), info->netname, + NET_NAME_PREDICTABLE, mhi_net_setup); + if (!ndev) + return -ENOMEM; + + SET_NETDEV_DEV(ndev, &mhi_dev->dev); + + err = mhi_net_newlink(mhi_dev, ndev); + if (err) { + free_netdev(ndev); + return err; + } + + return 0; +} + +static void mhi_net_remove(struct mhi_device *mhi_dev) +{ + struct mhi_net_dev *mhi_netdev = dev_get_drvdata(&mhi_dev->dev); + + mhi_net_dellink(mhi_dev, mhi_netdev->ndev); +} + +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_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 }, + {} +}; +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 "); +MODULE_DESCRIPTION("Network over MHI"); +MODULE_LICENSE("GPL v2");