Re: [RFC PATCH 11/12] soc: qcom: ipa: IPA rmnet interface

[Dan Williams]

On Tue, 2018-11-06 at 18:32 -0600, Alex Elder wrote:
> The IPA uses "rmnet" as a way to present remote network resources as
> if they were local to the AP.  IPA interfaces representing networks
> accessible via the modem are represented as rmnet interfaces,
> implemented by the "rmnet data driver" found here:
>     drivers/net/ethernet/qualcomm/rmnet/

It looks like there's a lot of overlap between this driver and that
one.  Ideally they would be a single driver which could automatically
select the IPA mode for appropriate hardware, or the IPA mode would be
a "subdriver" that bases itself heavily on the existing rmnet driver
even if it doesn't use the same packet movement functions.  Or
something like that.

But as Arnd stated, the ioctls won't fly.  They were also proposed for
the rmnet driver but they are better done as netlink, or via sysfs as
the existing qmi_wwan driver does for some of the same values.

Half the non-extended ioctls aren't even supported/used and should
simply be removed.

The extended ioctls should be evaluated as to whether they are really
needed (eg RMNET_IOCTL_GET_DRIVER_NAME).  I think most of the rest have
either been handled already via the 'rmnet' driver itself (like the MUX
channels using the vlan netlink attributes) or should be added via
netlink-type mechansims if they are really required.

In general, it would be good to get to a single 'rmnet' driver that has
a single API and supports as much hardware as possible.  There's too
much duplication currently.

Dan

> The IPA is able to perform aggregation of packets, as well as
> checksum offload.  These options (plus others, such as configuring
> MTU size) are configurable using an ioctl interface.  In addition,
> rmnet devices support multiplexing.
> 
> TX packets are handed to the data path layer, and when their
> transmission is complete the notification callback will be
> called.  The data path code posts RX packets to the hardware,
> and when they are filled they are supplied here by a receive
> notification callback.
> 
> The IPA driver currently does not support the modem shutting down
> (or crashing).  But the rmnet_ipa device roughly represents the
> availability of networks reachable by the modem.  If the modem is
> operational, an ipa_rmnet network device will be available.  Modem
> operation is managed by the remoteproc subsystem.
> 
> Note:  This portion of the driver will be heavily affected by
> planned rework on the data path code.
> 
> Signed-off-by: Alex Elder <elder@xxxxxxxxxx>
> ---
>  drivers/net/ipa/msm_rmnet.h    | 120 +++++
>  drivers/net/ipa/rmnet_config.h |  31 ++
>  drivers/net/ipa/rmnet_ipa.c    | 805
> +++++++++++++++++++++++++++++++++
>  3 files changed, 956 insertions(+)
>  create mode 100644 drivers/net/ipa/msm_rmnet.h
>  create mode 100644 drivers/net/ipa/rmnet_config.h
>  create mode 100644 drivers/net/ipa/rmnet_ipa.c
> 
> diff --git a/drivers/net/ipa/msm_rmnet.h
> b/drivers/net/ipa/msm_rmnet.h
> new file mode 100644
> index 000000000000..042380fd53fb
> --- /dev/null
> +++ b/drivers/net/ipa/msm_rmnet.h
> @@ -0,0 +1,120 @@
> +// SPDX-License-Identifier: GPL-2.0
> +
> +/* Copyright (c) 2018, The Linux Foundation. All rights reserved.
> + * Copyright (C) 2018 Linaro Ltd.
> + */
> +#ifndef _MSM_RMNET_H_
> +#define _MSM_RMNET_H_
> +
> +/* Bitmap macros for RmNET driver operation mode. */
> +#define RMNET_MODE_NONE	    0x00
> +#define RMNET_MODE_LLP_ETH  0x01
> +#define RMNET_MODE_LLP_IP   0x02
> +#define RMNET_MODE_QOS	    0x04
> +
> +/* IOCTL commands
> + * Values chosen to not conflict with other drivers in the ecosystem
> + */
> +
> +#define RMNET_IOCTL_SET_LLP_ETHERNET 0x000089f1 /* Set Ethernet
> protocol  */
> +#define RMNET_IOCTL_SET_LLP_IP	     0x000089f2 /* Set RAWIP
> protocol	  */
> +#define RMNET_IOCTL_GET_LLP	     0x000089f3 /* Get link
> protocol	  */
> +#define RMNET_IOCTL_SET_QOS_ENABLE   0x000089f4 /* Set QoS header
> enabled */
> +#define RMNET_IOCTL_SET_QOS_DISABLE  0x000089f5 /* Set QoS header
> disabled*/
> +#define RMNET_IOCTL_GET_QOS	     0x000089f6 /* Get QoS header
> state	  */
> +#define RMNET_IOCTL_GET_OPMODE	     0x000089f7 /* Get
> operation mode	  */
> +#define RMNET_IOCTL_OPEN	     0x000089f8 /* Open transport
> port	  */
> +#define RMNET_IOCTL_CLOSE	     0x000089f9 /* Close transport
> port	  */
> +#define RMNET_IOCTL_FLOW_ENABLE	     0x000089fa /* Flow
> enable		  */
> +#define RMNET_IOCTL_FLOW_DISABLE     0x000089fb /* Flow disable	
> 	  */
> +#define RMNET_IOCTL_FLOW_SET_HNDL    0x000089fc /* Set flow handle	
>   */
> +#define RMNET_IOCTL_EXTENDED	     0x000089fd /* Extended
> IOCTLs	  */
> +
> +/* RmNet Data Required IOCTLs */
> +#define RMNET_IOCTL_GET_SUPPORTED_FEATURES     0x0000	/* Get
> features	   */
> +#define RMNET_IOCTL_SET_MRU		       0x0001	/*
> Set MRU	   */
> +#define RMNET_IOCTL_GET_MRU		       0x0002	/*
> Get MRU	   */
> +#define RMNET_IOCTL_GET_EPID		       0x0003	/*
> Get endpoint ID */
> +#define RMNET_IOCTL_GET_DRIVER_NAME	       0x0004	/*
> Get driver name */
> +#define RMNET_IOCTL_ADD_MUX_CHANNEL	       0x0005	/*
> Add MUX ID	   */
> +#define RMNET_IOCTL_SET_EGRESS_DATA_FORMAT     0x0006	/* Set
> EDF	   */
> +#define RMNET_IOCTL_SET_INGRESS_DATA_FORMAT    0x0007	/* Set
> IDF	   */
> +#define RMNET_IOCTL_SET_AGGREGATION_COUNT      0x0008	/* Set
> agg count   */
> +#define RMNET_IOCTL_GET_AGGREGATION_COUNT      0x0009	/* Get
> agg count   */
> +#define RMNET_IOCTL_SET_AGGREGATION_SIZE       0x000a	/* Set
> agg size	   */
> +#define RMNET_IOCTL_GET_AGGREGATION_SIZE       0x000b	/* Get
> agg size	   */
> +#define RMNET_IOCTL_FLOW_CONTROL	       0x000c	/* Do
> flow control */
> +#define RMNET_IOCTL_GET_DFLT_CONTROL_CHANNEL   0x000d	/* For
> legacy use  */
> +#define RMNET_IOCTL_GET_HWSW_MAP	       0x000e	/* Get
> HW/SW map   */
> +#define RMNET_IOCTL_SET_RX_HEADROOM	       0x000f	/*
> RX Headroom	   */
> +#define RMNET_IOCTL_GET_EP_PAIR		       0x0010	
> /* Endpoint pair   */
> +#define RMNET_IOCTL_SET_QOS_VERSION	       0x0011	/*
> 8/6 byte QoS hdr*/
> +#define RMNET_IOCTL_GET_QOS_VERSION	       0x0012	/*
> 8/6 byte QoS hdr*/
> +#define RMNET_IOCTL_GET_SUPPORTED_QOS_MODES    0x0013	/* Get
> QoS modes   */
> +#define RMNET_IOCTL_SET_SLEEP_STATE	       0x0014	/*
> Set sleep state */
> +#define RMNET_IOCTL_SET_XLAT_DEV_INFO	       0x0015	/*
> xlat dev name   */
> +#define RMNET_IOCTL_DEREGISTER_DEV	       0x0016	/*
> Dereg a net dev */
> +#define RMNET_IOCTL_GET_SG_SUPPORT	       0x0017	/*
> Query sg support*/
> +
> +/* Return values for the RMNET_IOCTL_GET_SUPPORTED_FEATURES IOCTL */
> +#define RMNET_IOCTL_FEAT_NOTIFY_MUX_CHANNEL		BIT(0)
> +#define RMNET_IOCTL_FEAT_SET_EGRESS_DATA_FORMAT		BIT(1
> )
> +#define RMNET_IOCTL_FEAT_SET_INGRESS_DATA_FORMAT	BIT(2)
> +
> +/* Input values for the RMNET_IOCTL_SET_EGRESS_DATA_FORMAT IOCTL  */
> +#define RMNET_IOCTL_EGRESS_FORMAT_AGGREGATION		BIT(2)
> +#define RMNET_IOCTL_EGRESS_FORMAT_CHECKSUM		BIT(4)
> +
> +/* Input values for the RMNET_IOCTL_SET_INGRESS_DATA_FORMAT IOCTL */
> +#define RMNET_IOCTL_INGRESS_FORMAT_CHECKSUM		BIT(4)
> +#define RMNET_IOCTL_INGRESS_FORMAT_AGG_DATA		BIT(5)
> +
> +/* User space may not have this defined. */
> +#ifndef IFNAMSIZ
> +#define IFNAMSIZ 16
> +#endif
> +
> +struct rmnet_ioctl_extended_s {
> +	u32	extended_ioctl;
> +	union {
> +		u32	data; /* Generic data field for most
> extended IOCTLs */
> +
> +		/* Return values for
> +		 *    RMNET_IOCTL_GET_DRIVER_NAME
> +		 *    RMNET_IOCTL_GET_DFLT_CONTROL_CHANNEL
> +		 */
> +		char	if_name[IFNAMSIZ];
> +
> +		/* Input values for the RMNET_IOCTL_ADD_MUX_CHANNEL
> IOCTL */
> +		struct {
> +			u32	mux_id;
> +			char	vchannel_name[IFNAMSIZ];
> +		} rmnet_mux_val;
> +
> +		/* Input values for the RMNET_IOCTL_FLOW_CONTROL
> IOCTL */
> +		struct {
> +			u8	flow_mode;
> +			u8	mux_id;
> +		} flow_control_prop;
> +
> +		/* Return values for RMNET_IOCTL_GET_EP_PAIR */
> +		struct {
> +			u32	consumer_pipe_num;
> +			u32	producer_pipe_num;
> +		} ipa_ep_pair;
> +
> +		struct {
> +			u32	__data; /* Placeholder for legacy
> data*/
> +			u32	agg_size;
> +			u32	agg_count;
> +		} ingress_format;
> +	} u;
> +};
> +
> +struct rmnet_ioctl_data_s {
> +	union {
> +		u32	operation_mode;
> +		u32	tcm_handle;
> +	} u;
> +};
> +#endif /* _MSM_RMNET_H_ */
> diff --git a/drivers/net/ipa/rmnet_config.h
> b/drivers/net/ipa/rmnet_config.h
> new file mode 100644
> index 000000000000..3b9a549ca1bd
> --- /dev/null
> +++ b/drivers/net/ipa/rmnet_config.h
> @@ -0,0 +1,31 @@
> +// SPDX-License-Identifier: GPL-2.0
> +
> +/* Copyright (c) 2016-2018, The Linux Foundation. All rights
> reserved.
> + * Copyright (C) 2018 Linaro Ltd.
> + */
> +#ifndef _RMNET_CONFIG_H_
> +#define _RMNET_CONFIG_H_
> +
> +#include <linux/types.h>
> +
> +/* XXX We want to use struct rmnet_map_header, but that's currently
> defined in
> + * XXX     drivers/net/ethernet/qualcomm/rmnet/rmnet_map.h
> + * XXX We also want to use RMNET_MAP_GET_CD_BIT(Y), defined in the
> same file.
> + */
> +struct rmnet_map_header_s {
> +#ifndef RMNET_USE_BIG_ENDIAN_STRUCTS
> +	u8	pad_len		: 6,
> +		reserved_bit	: 1,
> +		cd_bit		: 1;
> +#else
> +	u8	cd_bit		: 1,
> +		reserved_bit	: 1,
> +		pad_len		: 6;
> +#endif /* RMNET_USE_BIG_ENDIAN_STRUCTS */
> +	u8	mux_id;
> +	u16	pkt_len;
> +}  __aligned(1);
> +
> +#define RMNET_MAP_GET_CD_BIT(Y) (((struct rmnet_map_header_s *)Y-
> >data)->cd_bit)
> +
> +#endif /* _RMNET_CONFIG_H_ */
> diff --git a/drivers/net/ipa/rmnet_ipa.c
> b/drivers/net/ipa/rmnet_ipa.c
> new file mode 100644
> index 000000000000..7006afe3a5ea
> --- /dev/null
> +++ b/drivers/net/ipa/rmnet_ipa.c
> @@ -0,0 +1,805 @@
> +// SPDX-License-Identifier: GPL-2.0
> +
> +/* Copyright (c) 2014-2018, The Linux Foundation. All rights
> reserved.
> + * Copyright (C) 2018 Linaro Ltd.
> + */
> +
> +/* WWAN Transport Network Driver. */
> +
> +#include <linux/completion.h>
> +#include <linux/errno.h>
> +#include <linux/if_arp.h>
> +#include <linux/interrupt.h>
> +#include <linux/init.h>
> +#include <linux/kernel.h>
> +#include <linux/module.h>
> +#include <linux/netdevice.h>
> +#include <linux/of_device.h>
> +#include <linux/string.h>
> +#include <linux/skbuff.h>
> +#include <linux/version.h>
> +#include <linux/workqueue.h>
> +#include <net/pkt_sched.h>
> +
> +#include "msm_rmnet.h"
> +#include "rmnet_config.h"
> +#include "ipa_qmi.h"
> +#include "ipa_i.h"
> +
> +#define DRIVER_NAME		"wwan_ioctl"
> +#define IPA_WWAN_DEV_NAME	"rmnet_ipa%d"
> +
> +#define MUX_CHANNEL_MAX		10	/* max mux channels
> */
> +
> +#define NAPI_WEIGHT		60
> +
> +#define WWAN_DATA_LEN		2000
> +#define HEADROOM_FOR_QMAP	8	/* for mux header */
> +#define TAILROOM		0	/* for padding by mux layer
> */
> +
> +#define DEFAULT_OUTSTANDING_HIGH	128
> +#define DEFAULT_OUTSTANDING_HIGH_CTL	(DEFAULT_OUTSTANDING_HIG
> H + 32)
> +#define DEFAULT_OUTSTANDING_LOW		64
> +
> +#define IPA_APPS_WWAN_CONS_RING_COUNT	256
> +#define IPA_APPS_WWAN_PROD_RING_COUNT	512
> +
> +static int ipa_rmnet_poll(struct napi_struct *napi, int budget);
> +
> +/** struct ipa_wwan_private - WWAN private data
> + * @net: network interface struct implemented by this driver
> + * @stats: iface statistics
> + * @outstanding_high: number of outstanding packets allowed
> + * @outstanding_low: number of outstanding packets which shall cause
> + *
> + * WWAN private - holds all relevant info about WWAN driver
> + */
> +struct ipa_wwan_private {
> +	struct net_device_stats stats;
> +	atomic_t outstanding_pkts;
> +	int outstanding_high_ctl;
> +	int outstanding_high;
> +	int outstanding_low;
> +	struct napi_struct napi;
> +};
> +
> +struct rmnet_ipa_context {
> +	struct net_device *dev;
> +	struct mutex mux_id_mutex;		/* protects
> mux_id[] */
> +	u32 mux_id_count;
> +	u32 mux_id[MUX_CHANNEL_MAX];
> +	u32 wan_prod_ep_id;
> +	u32 wan_cons_ep_id;
> +	struct mutex ep_setup_mutex;		/* endpoint
> setup/teardown */
> +};
> +
> +static bool initialized;	/* Avoid duplicate initialization */
> +
> +static struct rmnet_ipa_context rmnet_ipa_ctx_struct;
> +static struct rmnet_ipa_context *rmnet_ipa_ctx =
> &rmnet_ipa_ctx_struct;
> +
> +/** wwan_open() - Opens the wwan network interface */
> +static int ipa_wwan_open(struct net_device *dev)
> +{
> +	struct ipa_wwan_private *wwan_ptr = netdev_priv(dev);
> +
> +	napi_enable(&wwan_ptr->napi);
> +	netif_start_queue(dev);
> +
> +	return 0;
> +}
> +
> +/** ipa_wwan_stop() - Stops the wwan network interface. */
> +static int ipa_wwan_stop(struct net_device *dev)
> +{
> +	netif_stop_queue(dev);
> +
> +	return 0;
> +}
> +
> +/** ipa_wwan_xmit() - Transmits an skb.
> + *
> + * @skb: skb to be transmitted
> + * @dev: network device
> + *
> + * Return codes:
> + * NETDEV_TX_OK: Success
> + * NETDEV_TX_BUSY: Error while transmitting the skb. Try again later
> + */
> +static int ipa_wwan_xmit(struct sk_buff *skb, struct net_device
> *dev)
> +{
> +	struct ipa_wwan_private *wwan_ptr = netdev_priv(dev);
> +	unsigned int skb_len;
> +	int outstanding;
> +
> +	if (skb->protocol != htons(ETH_P_MAP)) {
> +		dev_kfree_skb_any(skb);
> +		dev->stats.tx_dropped++;
> +		return NETDEV_TX_OK;
> +	}
> +
> +	/* Control packets are sent even if queue is stopped.  We
> +	 * always honor the data and control high-water marks.
> +	 */
> +	outstanding = atomic_read(&wwan_ptr->outstanding_pkts);
> +	if (!RMNET_MAP_GET_CD_BIT(skb)) {	/* Data packet? */
> +		if (netif_queue_stopped(dev))
> +			return NETDEV_TX_BUSY;
> +		if (outstanding >= wwan_ptr->outstanding_high)
> +			return NETDEV_TX_BUSY;
> +	} else if (outstanding >= wwan_ptr->outstanding_high_ctl) {
> +		return NETDEV_TX_BUSY;
> +	}
> +
> +	/* both data packets and commands will be routed to
> +	 * IPA_CLIENT_Q6_WAN_CONS based on status configuration.
> +	 */
> +	skb_len = skb->len;
> +	if (ipa_tx_dp(IPA_CLIENT_APPS_WAN_PROD, skb))
> +		return NETDEV_TX_BUSY;
> +
> +	atomic_inc(&wwan_ptr->outstanding_pkts);
> +	dev->stats.tx_packets++;
> +	dev->stats.tx_bytes += skb_len;
> +
> +	return NETDEV_TX_OK;
> +}
> +
> +/** apps_ipa_tx_complete_notify() - Rx notify
> + *
> + * @priv: driver context
> + * @evt: event type
> + * @data: data provided with event
> + *
> + * Check that the packet is the one we sent and release it
> + * This function will be called in defered context in IPA wq.
> + */
> +static void apps_ipa_tx_complete_notify(void *priv, enum
> ipa_dp_evt_type evt,
> +					unsigned long data)
> +{
> +	struct ipa_wwan_private *wwan_ptr;
> +	struct net_device *dev = priv;
> +	struct sk_buff *skb;
> +
> +	skb = (struct sk_buff *)data;
> +
> +	if (dev != rmnet_ipa_ctx->dev) {
> +		dev_kfree_skb_any(skb);
> +		return;
> +	}
> +
> +	if (evt != IPA_WRITE_DONE) {
> +		ipa_err("unsupported evt on Tx callback, Drop the
> packet\n");
> +		dev_kfree_skb_any(skb);
> +		dev->stats.tx_dropped++;
> +		return;
> +	}
> +
> +	wwan_ptr = netdev_priv(dev);
> +	atomic_dec(&wwan_ptr->outstanding_pkts);
> +	__netif_tx_lock_bh(netdev_get_tx_queue(dev, 0));
> +	if (netif_queue_stopped(dev) &&
> +	    atomic_read(&wwan_ptr->outstanding_pkts) <
> +				wwan_ptr->outstanding_low) {
> +		netif_wake_queue(dev);
> +	}
> +
> +	__netif_tx_unlock_bh(netdev_get_tx_queue(dev, 0));
> +	dev_kfree_skb_any(skb);
> +}
> +
> +/** apps_ipa_packet_receive_notify() - Rx notify
> + *
> + * @priv: driver context
> + * @evt: event type
> + * @data: data provided with event
> + *
> + * IPA will pass a packet to the Linux network stack with skb->data
> + */
> +static void apps_ipa_packet_receive_notify(void *priv, enum
> ipa_dp_evt_type evt,
> +					   unsigned long data)
> +{
> +	struct ipa_wwan_private *wwan_ptr;
> +	struct net_device *dev = priv;
> +
> +	wwan_ptr = netdev_priv(dev);
> +	if (evt == IPA_RECEIVE) {
> +		struct sk_buff *skb = (struct sk_buff *)data;
> +		int ret;
> +		unsigned int packet_len = skb->len;
> +
> +		skb->dev = rmnet_ipa_ctx->dev;
> +		skb->protocol = htons(ETH_P_MAP);
> +
> +		ret = netif_receive_skb(skb);
> +		if (ret) {
> +			pr_err_ratelimited("fail on
> netif_receive_skb\n");
> +			dev->stats.rx_dropped++;
> +		}
> +		dev->stats.rx_packets++;
> +		dev->stats.rx_bytes += packet_len;
> +	} else if (evt == IPA_CLIENT_START_POLL) {
> +		napi_schedule(&wwan_ptr->napi);
> +	} else if (evt == IPA_CLIENT_COMP_NAPI) {
> +		napi_complete(&wwan_ptr->napi);
> +	} else {
> +		ipa_err("Invalid evt %d received in
> wan_ipa_receive\n", evt);
> +	}
> +}
> +
> +/** handle_ingress_format() - Ingress data format configuration */
> +static int handle_ingress_format(struct net_device *dev,
> +				 struct rmnet_ioctl_extended_s *in)
> +{
> +	enum ipa_cs_offload_en offload_type;
> +	enum ipa_client_type client;
> +	u32 metadata_offset;
> +	u32 rx_buffer_size;
> +	u32 channel_count;
> +	u32 length_offset;
> +	u32 header_size;
> +	bool aggr_active;
> +	u32 aggr_bytes;
> +	u32 aggr_count;
> +	u32 aggr_size;	/* in KB */
> +	u32 ep_id;
> +	int ret;
> +
> +	client = IPA_CLIENT_APPS_WAN_CONS;
> +	channel_count = IPA_APPS_WWAN_CONS_RING_COUNT;
> +	header_size = sizeof(struct rmnet_map_header_s);
> +	metadata_offset = offsetof(struct rmnet_map_header_s,
> mux_id);
> +	length_offset = offsetof(struct rmnet_map_header_s,
> pkt_len);
> +	offload_type = IPA_CS_OFFLOAD_NONE;
> +	aggr_bytes = IPA_GENERIC_AGGR_BYTE_LIMIT;
> +	aggr_count = IPA_GENERIC_AGGR_PKT_LIMIT;
> +	aggr_active = false;
> +
> +	if (in->u.data & RMNET_IOCTL_INGRESS_FORMAT_CHECKSUM)
> +		offload_type = IPA_CS_OFFLOAD_DL;
> +
> +	if (in->u.data & RMNET_IOCTL_INGRESS_FORMAT_AGG_DATA) {
> +		aggr_bytes = in->u.ingress_format.agg_size;
> +		aggr_count = in->u.ingress_format.agg_count;
> +		aggr_active = true;
> +	}
> +
> +	if (aggr_bytes > ipa_reg_aggr_max_byte_limit())
> +		return -EINVAL;
> +
> +	if (aggr_count > ipa_reg_aggr_max_packet_limit())
> +		return -EINVAL;
> +
> +	/* Compute the buffer size required to handle the requested
> +	 * aggregation byte limit.  The aggr_byte_limit value is
> +	 * expressed as a number of KB, but we derive that value
> +	 * after computing the buffer size to use (in bytes).  The
> +	 * buffer must be sufficient to hold one IPA_MTU-sized
> +	 * packet *after* the limit is reached.
> +	 *
> +	 * (Note that the rx_buffer_size value reflects only the
> +	 * space for data, not any standard metadata or headers.)
> +	 */
> +	rx_buffer_size = ipa_aggr_byte_limit_buf_size(aggr_bytes);
> +
> +	/* Account for the extra IPA_MTU past the limit in the
> +	 * buffer, and convert the result to the KB units the
> +	 * aggr_byte_limit uses.
> +	 */
> +	aggr_size = (rx_buffer_size - IPA_MTU) / SZ_1K;
> +
> +	mutex_lock(&rmnet_ipa_ctx->ep_setup_mutex);
> +
> +	if (rmnet_ipa_ctx->wan_cons_ep_id != IPA_EP_ID_BAD) {
> +		ret = -EBUSY;
> +		goto out_unlock;
> +	}
> +
> +	ret = ipa_ep_alloc(client);
> +	if (ret < 0)
> +		goto out_unlock;
> +	ep_id = ret;
> +
> +	/* Record our endpoint configuration parameters */
> +	ipa_endp_init_hdr_cons(ep_id, header_size, metadata_offset,
> +			       length_offset);
> +	ipa_endp_init_hdr_ext_cons(ep_id, 0, true);
> +	ipa_endp_init_aggr_cons(ep_id, aggr_size, aggr_count, true);
> +	ipa_endp_init_cfg_cons(ep_id, offload_type);
> +	ipa_endp_init_hdr_metadata_mask_cons(ep_id, 0xff000000);
> +	ipa_endp_status_cons(ep_id, !aggr_active);
> +
> +	ipa_ctx->ipa_client_apps_wan_cons_agg_gro = aggr_active;
> +
> +	ret = ipa_ep_setup(ep_id, channel_count, 1, rx_buffer_size,
> +			   apps_ipa_packet_receive_notify, dev);
> +	if (ret)
> +		ipa_ep_free(ep_id);
> +	else
> +		rmnet_ipa_ctx->wan_cons_ep_id = ep_id;
> +out_unlock:
> +	mutex_unlock(&rmnet_ipa_ctx->ep_setup_mutex);
> +
> +	return ret;
> +}
> +
> +/** handle_egress_format() - Egress data format configuration */
> +static int handle_egress_format(struct net_device *dev,
> +				struct rmnet_ioctl_extended_s *e)
> +{
> +	enum ipa_cs_offload_en offload_type;
> +	enum ipa_client_type dst_client;
> +	enum ipa_client_type client;
> +	enum ipa_aggr_type aggr_type;
> +	enum ipa_aggr_en aggr_en;
> +	u32 channel_count;
> +	u32 length_offset;
> +	u32 header_align;
> +	u32 header_offset;
> +	u32 header_size;
> +	u32 ep_id;
> +	int ret;
> +
> +	client = IPA_CLIENT_APPS_WAN_PROD;
> +	dst_client = IPA_CLIENT_APPS_LAN_CONS;
> +	channel_count = IPA_APPS_WWAN_PROD_RING_COUNT;
> +	header_size = sizeof(struct rmnet_map_header_s);
> +	offload_type = IPA_CS_OFFLOAD_NONE;
> +	aggr_en = IPA_BYPASS_AGGR;
> +	aggr_type = 0;	/* ignored if BYPASS */
> +	header_offset = 0;
> +	length_offset = 0;
> +	header_align = 0;
> +
> +	if (e->u.data & RMNET_IOCTL_EGRESS_FORMAT_CHECKSUM) {
> +		offload_type = IPA_CS_OFFLOAD_UL;
> +		header_offset = sizeof(struct rmnet_map_header_s) /
> 4;
> +		header_size += sizeof(u32);
> +	}
> +
> +	if (e->u.data & RMNET_IOCTL_EGRESS_FORMAT_AGGREGATION) {
> +		aggr_en = IPA_ENABLE_DEAGGR;
> +		aggr_type = IPA_QCMAP;
> +		length_offset = offsetof(struct rmnet_map_header_s,
> pkt_len);
> +		header_align = ilog2(sizeof(u32));
> +	}
> +
> +	mutex_lock(&rmnet_ipa_ctx->ep_setup_mutex);
> +
> +	if (rmnet_ipa_ctx->wan_prod_ep_id != IPA_EP_ID_BAD) {
> +		ret = -EBUSY;
> +		goto out_unlock;
> +	}
> +
> +	ret = ipa_ep_alloc(client);
> +	if (ret < 0)
> +		goto out_unlock;
> +	ep_id = ret;
> +
> +	if (aggr_en == IPA_ENABLE_DEAGGR &&
> !ipa_endp_aggr_support(ep_id)) {
> +		ret = -ENOTSUPP;
> +		goto out_unlock;
> +	}
> +
> +	/* We really do want 0 metadata offset */
> +	ipa_endp_init_hdr_prod(ep_id, header_size, 0,
> length_offset);
> +	ipa_endp_init_hdr_ext_prod(ep_id, header_align);
> +	ipa_endp_init_mode_prod(ep_id, IPA_BASIC, dst_client);
> +	ipa_endp_init_aggr_prod(ep_id, aggr_en, aggr_type);
> +	ipa_endp_init_cfg_prod(ep_id, offload_type, header_offset);
> +	ipa_endp_init_seq_prod(ep_id);
> +	ipa_endp_init_deaggr_prod(ep_id);
> +	/* Enable source notification status for exception packets
> +	 * (i.e. QMAP commands) to be routed to modem.
> +	 */
> +	ipa_endp_status_prod(ep_id, true, IPA_CLIENT_Q6_WAN_CONS);
> +
> +	/* Use a deferred interrupting no-op to reduce completion
> interrupts */
> +	ipa_no_intr_init(ep_id);
> +
> +	ret = ipa_ep_setup(ep_id, channel_count, 1, 0,
> +			   apps_ipa_tx_complete_notify, dev);
> +	if (ret)
> +		ipa_ep_free(ep_id);
> +	else
> +		rmnet_ipa_ctx->wan_prod_ep_id = ep_id;
> +
> +out_unlock:
> +	mutex_unlock(&rmnet_ipa_ctx->ep_setup_mutex);
> +
> +	return ret;
> +}
> +
> +/** ipa_wwan_add_mux_channel() - add a mux_id */
> +static int ipa_wwan_add_mux_channel(u32 mux_id)
> +{
> +	int ret;
> +	u32 i;
> +
> +	mutex_lock(&rmnet_ipa_ctx->mux_id_mutex);
> +
> +	if (rmnet_ipa_ctx->mux_id_count >= MUX_CHANNEL_MAX) {
> +		ret = -EFAULT;
> +		goto out;
> +	}
> +
> +	for (i = 0; i < rmnet_ipa_ctx->mux_id_count; i++)
> +		if (mux_id == rmnet_ipa_ctx->mux_id[i])
> +			break;
> +
> +	/* Record the mux_id if it hasn't already been seen */
> +	if (i == rmnet_ipa_ctx->mux_id_count)
> +		rmnet_ipa_ctx->mux_id[rmnet_ipa_ctx->mux_id_count++] 
> = mux_id;
> +	ret = 0;
> +out:
> +	mutex_unlock(&rmnet_ipa_ctx->mux_id_mutex);
> +
> +	return ret;
> +}
> +
> +/** ipa_wwan_ioctl_extended() - rmnet extended I/O control */
> +static int ipa_wwan_ioctl_extended(struct net_device *dev, void
> __user *data)
> +{
> +	struct rmnet_ioctl_extended_s edata = { };
> +	size_t size = sizeof(edata);
> +
> +	if (copy_from_user(&edata, data, size))
> +		return -EFAULT;
> +
> +	switch (edata.extended_ioctl) {
> +	case RMNET_IOCTL_GET_SUPPORTED_FEATURES:	/* Get
> features */
> +		edata.u.data = RMNET_IOCTL_FEAT_NOTIFY_MUX_CHANNEL;
> +		edata.u.data |=
> RMNET_IOCTL_FEAT_SET_EGRESS_DATA_FORMAT;
> +		edata.u.data |=
> RMNET_IOCTL_FEAT_SET_INGRESS_DATA_FORMAT;
> +		goto copy_out;
> +
> +	case RMNET_IOCTL_GET_EPID:			/* Get
> endpoint ID */
> +		edata.u.data = 1;
> +		goto copy_out;
> +
> +	case RMNET_IOCTL_GET_DRIVER_NAME:		/* Get
> driver name */
> +		memcpy(&edata.u.if_name, rmnet_ipa_ctx->dev->name,
> IFNAMSIZ);
> +		goto copy_out;
> +
> +	case RMNET_IOCTL_ADD_MUX_CHANNEL:		/* Add MUX
> ID */
> +		return
> ipa_wwan_add_mux_channel(edata.u.rmnet_mux_val.mux_id);
> +
> +	case RMNET_IOCTL_SET_EGRESS_DATA_FORMAT:	/* Egress
> data format */
> +		return handle_egress_format(dev, &edata) ? -EFAULT :
> 0;
> +
> +	case RMNET_IOCTL_SET_INGRESS_DATA_FORMAT:	/* Ingress
> format */
> +		return handle_ingress_format(dev, &edata) ? -EFAULT
> : 0;
> +
> +	case RMNET_IOCTL_GET_EP_PAIR:			/* Get
> endpoint pair */
> +		edata.u.ipa_ep_pair.consumer_pipe_num =
> +				ipa_client_ep_id(IPA_CLIENT_APPS_WAN
> _PROD);
> +		edata.u.ipa_ep_pair.producer_pipe_num =
> +				ipa_client_ep_id(IPA_CLIENT_APPS_WAN
> _CONS);
> +		goto copy_out;
> +
> +	case RMNET_IOCTL_GET_SG_SUPPORT:		/* Get SG
> support */
> +		edata.u.data = 1;	/* Scatter/gather is always
> supported */
> +		goto copy_out;
> +
> +	/* Unsupported requests */
> +	case RMNET_IOCTL_SET_MRU:			/* Set MRU
> */
> +	case RMNET_IOCTL_GET_MRU:			/* Get MRU
> */
> +	case RMNET_IOCTL_GET_AGGREGATION_COUNT:		/*
> Get agg count */
> +	case RMNET_IOCTL_SET_AGGREGATION_COUNT:		/*
> Set agg count */
> +	case RMNET_IOCTL_GET_AGGREGATION_SIZE:		/* Get
> agg size */
> +	case RMNET_IOCTL_SET_AGGREGATION_SIZE:		/* Set
> agg size */
> +	case RMNET_IOCTL_FLOW_CONTROL:			/* Do
> flow control */
> +	case RMNET_IOCTL_GET_DFLT_CONTROL_CHANNEL:	/* For
> legacy use */
> +	case RMNET_IOCTL_GET_HWSW_MAP:			/* Get
> HW/SW map */
> +	case RMNET_IOCTL_SET_RX_HEADROOM:		/* Set RX
> Headroom */
> +	case RMNET_IOCTL_SET_QOS_VERSION:		/* Set 8/6
> byte QoS */
> +	case RMNET_IOCTL_GET_QOS_VERSION:		/* Get 8/6
> byte QoS */
> +	case RMNET_IOCTL_GET_SUPPORTED_QOS_MODES:	/* Get QoS
> modes */
> +	case RMNET_IOCTL_SET_SLEEP_STATE:		/* Set
> sleep state */
> +	case RMNET_IOCTL_SET_XLAT_DEV_INFO:		/* xlat
> dev name */
> +	case RMNET_IOCTL_DEREGISTER_DEV:		/*
> Deregister netdev */
> +		return -ENOTSUPP;	/* Defined, but unsupported
> command */
> +
> +	default:
> +		return -EINVAL;		/* Invalid
> (unrecognized) command */
> +	}
> +
> +copy_out:
> +	return copy_to_user(data, &edata, size) ? -EFAULT : 0;
> +}
> +
> +/** ipa_wwan_ioctl() - I/O control for wwan network driver */
> +static int ipa_wwan_ioctl(struct net_device *dev, struct ifreq *ifr,
> int cmd)
> +{
> +	struct rmnet_ioctl_data_s ioctl_data = { };
> +	void __user *data;
> +	size_t size;
> +
> +	data = ifr->ifr_ifru.ifru_data;
> +	size = sizeof(ioctl_data);
> +
> +	switch (cmd) {
> +	/* These features are implied; alternatives are not
> supported */
> +	case RMNET_IOCTL_SET_LLP_IP:		/* RAW IP
> protocol */
> +	case RMNET_IOCTL_SET_QOS_DISABLE:	/* QoS header
> disabled */
> +		return 0;
> +
> +	/* These features are not supported; use alternatives */
> +	case RMNET_IOCTL_SET_LLP_ETHERNET:	/* Ethernet
> protocol */
> +	case RMNET_IOCTL_SET_QOS_ENABLE:	/* QoS header
> enabled */
> +	case RMNET_IOCTL_GET_OPMODE:		/* Get operation
> mode */
> +	case RMNET_IOCTL_FLOW_ENABLE:		/* Flow enable
> */
> +	case RMNET_IOCTL_FLOW_DISABLE:		/* Flow
> disable */
> +	case RMNET_IOCTL_FLOW_SET_HNDL:		/* Set flow
> handle */
> +		return -ENOTSUPP;
> +
> +	case RMNET_IOCTL_GET_LLP:		/* Get link
> protocol */
> +		ioctl_data.u.operation_mode = RMNET_MODE_LLP_IP;
> +		goto copy_out;
> +
> +	case RMNET_IOCTL_GET_QOS:		/* Get QoS header
> state */
> +		ioctl_data.u.operation_mode = RMNET_MODE_NONE;
> +		goto copy_out;
> +
> +	case RMNET_IOCTL_OPEN:			/* Open
> transport port */
> +	case RMNET_IOCTL_CLOSE:			/* Close
> transport port */
> +		return 0;
> +
> +	case RMNET_IOCTL_EXTENDED:		/* Extended IOCTLs
> */
> +		return ipa_wwan_ioctl_extended(dev, data);
> +
> +	default:
> +		return -EINVAL;
> +	}
> +
> +copy_out:
> +	return copy_to_user(data, &ioctl_data, size) ? -EFAULT : 0;
> +}
> +
> +static const struct net_device_ops ipa_wwan_ops_ip = {
> +	.ndo_open	= ipa_wwan_open,
> +	.ndo_stop	= ipa_wwan_stop,
> +	.ndo_start_xmit	= ipa_wwan_xmit,
> +	.ndo_do_ioctl	= ipa_wwan_ioctl,
> +};
> +
> +/** wwan_setup() - Setup the wwan network driver */
> +static void ipa_wwan_setup(struct net_device *dev)
> +{
> +	dev->netdev_ops = &ipa_wwan_ops_ip;
> +	ether_setup(dev);
> +	dev->header_ops = NULL;	 /* No header (override
> ether_setup() value) */
> +	dev->type = ARPHRD_RAWIP;
> +	dev->hard_header_len = 0;
> +	dev->max_mtu = WWAN_DATA_LEN;
> +	dev->mtu = dev->max_mtu;
> +	dev->addr_len = 0;
> +	dev->flags &= ~(IFF_BROADCAST | IFF_MULTICAST);
> +	dev->needed_headroom = HEADROOM_FOR_QMAP;
> +	dev->needed_tailroom = TAILROOM;
> +	dev->watchdog_timeo = msecs_to_jiffies(10 * MSEC_PER_SEC);
> +}
> +
> +/** ipa_wwan_probe() - Network probe function */
> +static int ipa_wwan_probe(struct platform_device *pdev)
> +{
> +	struct ipa_wwan_private *wwan_ptr;
> +	struct net_device *dev;
> +	int ret;
> +
> +	mutex_init(&rmnet_ipa_ctx->ep_setup_mutex);
> +	mutex_init(&rmnet_ipa_ctx->mux_id_mutex);
> +
> +	/* Mark client handles bad until we initialize them */
> +	rmnet_ipa_ctx->wan_prod_ep_id = IPA_EP_ID_BAD;
> +	rmnet_ipa_ctx->wan_cons_ep_id = IPA_EP_ID_BAD;
> +
> +	ret = ipa_modem_smem_init();
> +	if (ret)
> +		goto err_clear_ctx;
> +
> +	/* start A7 QMI service/client */
> +	ipa_qmi_init();
> +
> +	/* initialize wan-driver netdev */
> +	dev = alloc_netdev(sizeof(struct ipa_wwan_private),
> +			   IPA_WWAN_DEV_NAME,
> +			   NET_NAME_UNKNOWN,
> +			   ipa_wwan_setup);
> +	if (!dev) {
> +		ipa_err("no memory for netdev\n");
> +		ret = -ENOMEM;
> +		goto err_clear_ctx;
> +	}
> +	rmnet_ipa_ctx->dev = dev;
> +	wwan_ptr = netdev_priv(dev);
> +	wwan_ptr->outstanding_high_ctl =
> DEFAULT_OUTSTANDING_HIGH_CTL;
> +	wwan_ptr->outstanding_high = DEFAULT_OUTSTANDING_HIGH;
> +	wwan_ptr->outstanding_low = DEFAULT_OUTSTANDING_LOW;
> +	atomic_set(&wwan_ptr->outstanding_pkts, 0);
> +
> +	/* Enable SG support in netdevice. */
> +	dev->hw_features |= NETIF_F_SG;
> +
> +	netif_napi_add(dev, &wwan_ptr->napi, ipa_rmnet_poll,
> NAPI_WEIGHT);
> +	ret = register_netdev(dev);
> +	if (ret) {
> +		ipa_err("unable to register ipa_netdev %d rc=%d\n",
> 0, ret);
> +		goto err_napi_del;
> +	}
> +
> +	/* offline charging mode */
> +	ipa_proxy_clk_unvote();
> +
> +	/* Till the system is suspended, we keep the clock open */
> +	ipa_client_add();
> +
> +	initialized = true;
> +
> +	return 0;
> +
> +err_napi_del:
> +	netif_napi_del(&wwan_ptr->napi);
> +	free_netdev(dev);
> +err_clear_ctx:
> +	memset(&rmnet_ipa_ctx_struct, 0,
> sizeof(rmnet_ipa_ctx_struct));
> +
> +	return ret;
> +}
> +
> +static int ipa_wwan_remove(struct platform_device *pdev)
> +{
> +	struct ipa_wwan_private *wwan_ptr =
> netdev_priv(rmnet_ipa_ctx->dev);
> +
> +	dev_info(&pdev->dev, "rmnet_ipa started
> deinitialization\n");
> +
> +	mutex_lock(&rmnet_ipa_ctx->ep_setup_mutex);
> +
> +	ipa_client_add();
> +
> +	if (rmnet_ipa_ctx->wan_cons_ep_id != IPA_EP_ID_BAD) {
> +		ipa_ep_teardown(rmnet_ipa_ctx->wan_cons_ep_id);
> +		rmnet_ipa_ctx->wan_cons_ep_id = IPA_EP_ID_BAD;
> +	}
> +
> +	if (rmnet_ipa_ctx->wan_prod_ep_id != IPA_EP_ID_BAD) {
> +		ipa_ep_teardown(rmnet_ipa_ctx->wan_prod_ep_id);
> +		rmnet_ipa_ctx->wan_prod_ep_id = IPA_EP_ID_BAD;
> +	}
> +
> +	ipa_client_remove();
> +
> +	netif_napi_del(&wwan_ptr->napi);
> +	mutex_unlock(&rmnet_ipa_ctx->ep_setup_mutex);
> +	unregister_netdev(rmnet_ipa_ctx->dev);
> +
> +	if (rmnet_ipa_ctx->dev)
> +		free_netdev(rmnet_ipa_ctx->dev);
> +	rmnet_ipa_ctx->dev = NULL;
> +
> +	mutex_destroy(&rmnet_ipa_ctx->mux_id_mutex);
> +	mutex_destroy(&rmnet_ipa_ctx->ep_setup_mutex);
> +
> +	initialized = false;
> +
> +	dev_info(&pdev->dev, "rmnet_ipa completed
> deinitialization\n");
> +
> +	return 0;
> +}
> +
> +/** rmnet_ipa_ap_suspend() - suspend callback for runtime_pm
> + * @dev: pointer to device
> + *
> + * This callback will be invoked by the runtime_pm framework when an
> AP suspend
> + * operation is invoked, usually by pressing a suspend button.
> + *
> + * Returns -EAGAIN to runtime_pm framework in case there are pending
> packets
> + * in the Tx queue. This will postpone the suspend operation until
> all the
> + * pending packets will be transmitted.
> + *
> + * In case there are no packets to send, releases the WWAN0_PROD
> entity.
> + * As an outcome, the number of IPA active clients should be
> decremented
> + * until IPA clocks can be gated.
> + */
> +static int rmnet_ipa_ap_suspend(struct device *dev)
> +{
> +	struct net_device *netdev = rmnet_ipa_ctx->dev;
> +	struct ipa_wwan_private *wwan_ptr;
> +	int ret;
> +
> +	if (!netdev) {
> +		ipa_err("netdev is NULL.\n");
> +		ret = 0;
> +		goto bail;
> +	}
> +
> +	netif_tx_lock_bh(netdev);
> +	wwan_ptr = netdev_priv(netdev);
> +	if (!wwan_ptr) {
> +		ipa_err("wwan_ptr is NULL.\n");
> +		ret = 0;
> +		goto unlock_and_bail;
> +	}
> +
> +	/* Do not allow A7 to suspend in case there are outstanding
> packets */
> +	if (atomic_read(&wwan_ptr->outstanding_pkts) != 0) {
> +		ret = -EAGAIN;
> +		goto unlock_and_bail;
> +	}
> +
> +	/* Make sure that there is no Tx operation ongoing */
> +	netif_stop_queue(netdev);
> +
> +	ret = 0;
> +	ipa_client_remove();
> +
> +unlock_and_bail:
> +	netif_tx_unlock_bh(netdev);
> +bail:
> +
> +	return ret;
> +}
> +
> +/** rmnet_ipa_ap_resume() - resume callback for runtime_pm
> + * @dev: pointer to device
> + *
> + * This callback will be invoked by the runtime_pm framework when an
> AP resume
> + * operation is invoked.
> + *
> + * Enables the network interface queue and returns success to the
> + * runtime_pm framework.
> + */
> +static int rmnet_ipa_ap_resume(struct device *dev)
> +{
> +	struct net_device *netdev = rmnet_ipa_ctx->dev;
> +
> +	ipa_client_add();
> +	if (netdev)
> +		netif_wake_queue(netdev);
> +
> +	return 0;
> +}
> +
> +static const struct of_device_id rmnet_ipa_dt_match[] = {
> +	{.compatible = "qcom,rmnet-ipa"},
> +	{},
> +};
> +MODULE_DEVICE_TABLE(of, rmnet_ipa_dt_match);
> +
> +static const struct dev_pm_ops rmnet_ipa_pm_ops = {
> +	.suspend_noirq = rmnet_ipa_ap_suspend,
> +	.resume_noirq = rmnet_ipa_ap_resume,
> +};
> +
> +static struct platform_driver rmnet_ipa_driver = {
> +	.driver = {
> +		.name = "rmnet_ipa",
> +		.owner = THIS_MODULE,
> +		.pm = &rmnet_ipa_pm_ops,
> +		.of_match_table = rmnet_ipa_dt_match,
> +	},
> +	.probe = ipa_wwan_probe,
> +	.remove = ipa_wwan_remove,
> +};
> +
> +int ipa_wwan_init(void)
> +{
> +	if (initialized)
> +		return 0;
> +
> +	return platform_driver_register(&rmnet_ipa_driver);
> +}
> +
> +void ipa_wwan_cleanup(void)
> +{
> +	platform_driver_unregister(&rmnet_ipa_driver);
> +	memset(&rmnet_ipa_ctx_struct, 0,
> sizeof(rmnet_ipa_ctx_struct));
> +}
> +
> +static int ipa_rmnet_poll(struct napi_struct *napi, int budget)
> +{
> +	return ipa_rx_poll(rmnet_ipa_ctx->wan_cons_ep_id, budget);
> +}
> +
> +MODULE_DESCRIPTION("WWAN Network Interface");
> +MODULE_LICENSE("GPL v2");