net: wwan: iosm: Enable M.2 7360 WWAN card support

This patch enables Intel M.2 7360 WWAN card support on
IOSM Driver.

Control path implementation is a reuse whereas data path
implementation it uses a different protocol called as MUX
Aggregation. The major portion of this patch covers the MUX
Aggregation protocol implementation used for IP traffic
communication.

For M.2 7360 WWAN card, driver exposes 2 wwan AT ports for
control communication.  The user space application or the
modem manager to use wwan AT port for data path establishment.

During probe, driver reads the mux protocol device capability
register to know the mux protocol version supported by device.
Base on which the right mux protocol is initialized for data
path communication.

An overview of an Aggregation Protocol
1>  An IP packet is encapsulated with 16 octet padding header
    to form a Datagram & the start offset of the Datagram is
    indexed into Datagram Header (DH).
2>  Multiple such Datagrams are composed & the start offset of
    each DH is indexed into Datagram Table Header (DTH).
3>  The Datagram Table (DT) is IP session specific & table_length
    item in DTH holds the number of composed datagram pertaining
    to that particular IP session.
4>  And finally the offset of first DTH is indexed into DBH (Datagram
    Block Header).

So in TX/RX flow Datagram Block (Datagram Block Header + Payload)is
exchanged between driver & device.

Signed-off-by: M Chetan Kumar <m.chetan.kumar@linux.intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

drivers/net/wwan/iosm/iosm_ipc_imem.c

@@ -114,17 +114,35 @@ ipc_imem_fast_update_timer_cb(struct hrtimer *hr_timer)
 	return HRTIMER_NORESTART;
 }
 
+static int ipc_imem_tq_adb_timer_cb(struct iosm_imem *ipc_imem, int arg,
+				    void *msg, size_t size)
+{
+	ipc_mux_ul_adb_finish(ipc_imem->mux);
+	return 0;
+}
+
+static enum hrtimer_restart
+ipc_imem_adb_timer_cb(struct hrtimer *hr_timer)
+{
+	struct iosm_imem *ipc_imem =
+		container_of(hr_timer, struct iosm_imem, adb_timer);
+
+	ipc_task_queue_send_task(ipc_imem, ipc_imem_tq_adb_timer_cb, 0,
+				 NULL, 0, false);
+	return HRTIMER_NORESTART;
+}
+
 static int ipc_imem_setup_cp_mux_cap_init(struct iosm_imem *ipc_imem,
 					  struct ipc_mux_config *cfg)
 {
 	ipc_mmio_update_cp_capability(ipc_imem->mmio);
 
-	if (!ipc_imem->mmio->has_mux_lite) {
+	if (ipc_imem->mmio->mux_protocol == MUX_UNKNOWN) {
 		dev_err(ipc_imem->dev, "Failed to get Mux capability.");
 		return -EINVAL;
 	}
 
-	cfg->protocol = MUX_LITE;
+	cfg->protocol = ipc_imem->mmio->mux_protocol;
 
 	cfg->ul_flow = (ipc_imem->mmio->has_ul_flow_credit == 1) ?
 			       MUX_UL_ON_CREDITS :
@@ -153,6 +171,10 @@ void ipc_imem_msg_send_feature_set(struct iosm_imem *ipc_imem,
 				      IPC_MSG_PREP_FEATURE_SET, &prep_args);
 }
 
+/**
+ * ipc_imem_td_update_timer_start - Starts the TD Update Timer if not started.
+ * @ipc_imem:                       Pointer to imem data-struct
+ */
 void ipc_imem_td_update_timer_start(struct iosm_imem *ipc_imem)
 {
 	/* Use the TD update timer only in the runtime phase */
@@ -179,6 +201,21 @@ void ipc_imem_hrtimer_stop(struct hrtimer *hr_timer)
 		hrtimer_cancel(hr_timer);
 }
 
+/**
+ * ipc_imem_adb_timer_start -	Starts the adb Timer if not starting.
+ * @ipc_imem:			Pointer to imem data-struct
+ */
+void ipc_imem_adb_timer_start(struct iosm_imem *ipc_imem)
+{
+	if (!hrtimer_active(&ipc_imem->adb_timer)) {
+		ipc_imem->hrtimer_period =
+			ktime_set(0, IOSM_AGGR_MUX_ADB_FINISH_TIMEOUT_NSEC);
+		hrtimer_start(&ipc_imem->adb_timer,
+			      ipc_imem->hrtimer_period,
+			      HRTIMER_MODE_REL);
+	}
+}
+
 bool ipc_imem_ul_write_td(struct iosm_imem *ipc_imem)
 {
 	struct ipc_mem_channel *channel;
@@ -550,6 +587,11 @@ static void ipc_imem_run_state_worker(struct work_struct *instance)
 	while (ctrl_chl_idx < IPC_MEM_MAX_CHANNELS) {
 		if (!ipc_chnl_cfg_get(&chnl_cfg_port, ctrl_chl_idx)) {
 			ipc_imem->ipc_port[ctrl_chl_idx] = NULL;
+			if (ipc_imem->pcie->pci->device == INTEL_CP_DEVICE_7360_ID &&
+			    chnl_cfg_port.wwan_port_type == WWAN_PORT_MBIM) {
+				ctrl_chl_idx++;
+				continue;
+			}
 			if (chnl_cfg_port.wwan_port_type != WWAN_PORT_UNKNOWN) {
 				ipc_imem_channel_init(ipc_imem, IPC_CTYPE_CTRL,
 						      chnl_cfg_port,
@@ -680,8 +722,11 @@ static void ipc_imem_handle_irq(struct iosm_imem *ipc_imem, int irq)
 	}
 
 	/* Try to generate new ADB or ADGH. */
-	if (ipc_mux_ul_data_encode(ipc_imem->mux))
+	if (ipc_mux_ul_data_encode(ipc_imem->mux)) {
 		ipc_imem_td_update_timer_start(ipc_imem);
+		if (ipc_imem->mux->protocol == MUX_AGGREGATION)
+			ipc_imem_adb_timer_start(ipc_imem);
+	}
 
 	/* Continue the send procedure with accumulated SIO or NETIF packets.
 	 * Reset the debounce flags.
@@ -1330,6 +1375,9 @@ struct iosm_imem *ipc_imem_init(struct iosm_pcie *pcie, unsigned int device_id,
 		     HRTIMER_MODE_REL);
 	ipc_imem->td_alloc_timer.function = ipc_imem_td_alloc_timer_cb;
 
+	hrtimer_init(&ipc_imem->adb_timer, CLOCK_MONOTONIC, HRTIMER_MODE_REL);
+	ipc_imem->adb_timer.function = ipc_imem_adb_timer_cb;
+
 	if (ipc_imem_config(ipc_imem)) {
 		dev_err(ipc_imem->dev, "failed to initialize the imem");
 		goto imem_config_fail;

drivers/net/wwan/iosm/iosm_ipc_imem.h

@@ -317,6 +317,7 @@ enum ipc_phase {
  * @tdupdate_timer:		Delay the TD update doorbell.
  * @fast_update_timer:		forced head pointer update delay timer.
  * @td_alloc_timer:		Timer for DL pipe TD allocation retry
+ * @adb_timer:			Timer for finishing the ADB.
  * @rom_exit_code:		Mapped boot rom exit code.
  * @enter_runtime:		1 means the transition to runtime phase was
  *				executed.
@@ -364,6 +365,7 @@ struct iosm_imem {
 	struct hrtimer tdupdate_timer;
 	struct hrtimer fast_update_timer;
 	struct hrtimer td_alloc_timer;
+	struct hrtimer adb_timer;
 	enum rom_exit_code rom_exit_code;
 	u32 enter_runtime;
 	struct completion ul_pend_sem;
@@ -593,4 +595,7 @@ void ipc_imem_channel_init(struct iosm_imem *ipc_imem, enum ipc_ctype ctype,
  * Returns: 0 on success, -1 on failure
  */
 int ipc_imem_devlink_trigger_chip_info(struct iosm_imem *ipc_imem);
+
+void ipc_imem_adb_timer_start(struct iosm_imem *ipc_imem);
+
 #endif

drivers/net/wwan/iosm/iosm_ipc_mmio.c

@@ -10,6 +10,7 @@
 #include <linux/slab.h>
 
 #include "iosm_ipc_mmio.h"
+#include "iosm_ipc_mux.h"
 
 /* Definition of MMIO offsets
  * note that MMIO_CI offsets are relative to end of chip info structure
@@ -71,8 +72,9 @@ void ipc_mmio_update_cp_capability(struct iosm_mmio *ipc_mmio)
 	ver = ipc_mmio_get_cp_version(ipc_mmio);
 	cp_cap = ioread32(ipc_mmio->base + ipc_mmio->offset.cp_capability);
 
-	ipc_mmio->has_mux_lite = (ver >= IOSM_CP_VERSION) &&
-				 !(cp_cap & DL_AGGR) && !(cp_cap & UL_AGGR);
+	ipc_mmio->mux_protocol = ((ver >= IOSM_CP_VERSION) && (cp_cap &
+				 (UL_AGGR | DL_AGGR))) ? MUX_AGGREGATION
+				 : MUX_LITE;
 
 	ipc_mmio->has_ul_flow_credit =
 		(ver >= IOSM_CP_VERSION) && (cp_cap & UL_FLOW_CREDIT);

drivers/net/wwan/iosm/iosm_ipc_mmio.h

@@ -72,7 +72,7 @@ struct mmio_offset {
  * @context_info_addr:	Physical base address of context info structure
  * @chip_info_version:	Version of chip info structure
  * @chip_info_size:	Size of chip info structure
- * @has_mux_lite:	It doesn't support mux aggergation
+ * @mux_protocol:	mux protocol
  * @has_ul_flow_credit:	Ul flow credit support
  * @has_slp_no_prot:	Device sleep no protocol support
  * @has_mcr_support:	Usage of mcr support
@@ -84,8 +84,8 @@ struct iosm_mmio {
 	phys_addr_t context_info_addr;
 	unsigned int chip_info_version;
 	unsigned int chip_info_size;
-	u8 has_mux_lite:1,
-	   has_ul_flow_credit:1,
+	u32 mux_protocol;
+	u8 has_ul_flow_credit:1,
 	   has_slp_no_prot:1,
 	   has_mcr_support:1;
 };

drivers/net/wwan/iosm/iosm_ipc_mux.c

@@ -279,9 +279,10 @@ struct iosm_mux *ipc_mux_init(struct ipc_mux_config *mux_cfg,
 			      struct iosm_imem *imem)
 {
 	struct iosm_mux *ipc_mux = kzalloc(sizeof(*ipc_mux), GFP_KERNEL);
-	int i, ul_tds, ul_td_size;
+	int i, j, ul_tds, ul_td_size;
 	struct sk_buff_head *free_list;
 	struct sk_buff *skb;
+	int qlt_size;
 
 	if (!ipc_mux)
 		return NULL;
@@ -321,6 +322,24 @@ struct iosm_mux *ipc_mux_init(struct ipc_mux_config *mux_cfg,
 	ipc_mux->channel_id = -1;
 	ipc_mux->channel = NULL;
 
+	if (ipc_mux->protocol != MUX_LITE) {
+		qlt_size = offsetof(struct mux_qlth, ql) +
+				MUX_QUEUE_LEVEL * sizeof(struct mux_qlth_ql);
+
+		for (i = 0; i < IPC_MEM_MUX_IP_SESSION_ENTRIES; i++) {
+			ipc_mux->ul_adb.pp_qlt[i] = kzalloc(qlt_size,
+							    GFP_ATOMIC);
+			if (!ipc_mux->ul_adb.pp_qlt[i]) {
+				for (j = i - 1; j >= 0; j--)
+					kfree(ipc_mux->ul_adb.pp_qlt[j]);
+				return NULL;
+			}
+		}
+
+		ul_td_size = IPC_MEM_MAX_UL_ADB_BUF_SIZE;
+		ul_tds = IPC_MEM_MAX_TDS_MUX_AGGR_UL;
+	}
+
 	/* Allocate the list of UL ADB. */
 	for (i = 0; i < ul_tds; i++) {
 		dma_addr_t mapping;

drivers/net/wwan/iosm/iosm_ipc_mux.h

@@ -8,9 +8,12 @@
 
 #include "iosm_ipc_protocol.h"
 
-/* Size of the buffer for the IP MUX data buffer. */
-#define IPC_MEM_MAX_DL_MUX_BUF_SIZE (16 * 1024)
-#define IPC_MEM_MAX_UL_ADB_BUF_SIZE IPC_MEM_MAX_DL_MUX_BUF_SIZE
+#define IPC_MEM_MAX_UL_DG_ENTRIES	100
+#define IPC_MEM_MAX_TDS_MUX_AGGR_UL	60
+
+#define IPC_MEM_MAX_ADB_BUF_SIZE (16 * 1024)
+#define IPC_MEM_MAX_UL_ADB_BUF_SIZE IPC_MEM_MAX_ADB_BUF_SIZE
+#define IPC_MEM_MAX_DL_ADB_BUF_SIZE IPC_MEM_MAX_ADB_BUF_SIZE
 
 /* Size of the buffer for the IP MUX Lite data buffer. */
 #define IPC_MEM_MAX_DL_MUX_LITE_BUF_SIZE (2 * 1024)
@@ -167,6 +170,7 @@ enum mux_state {
 enum ipc_mux_protocol {
 	MUX_UNKNOWN,
 	MUX_LITE,
+	MUX_AGGREGATION,
 };
 
 /* Supported UL data transfer methods. */
@@ -192,24 +196,111 @@ struct mux_session {
 	   flush:1; /* flush net interface ? */
 };
 
-/* State of a single UL data block. */
+/**
+ * struct mux_adth_dg - Structure of the datagram in the Aggregated Datagram
+ *			Table Header.
+ * @datagram_index :	Index (in bytes) to the k-th datagram in the table.
+ *			Index shall count from the start of the block including
+ *			the 16-byte header. This value shall be non-zero.
+ * @datagram_length:	Length of the k-th datagram including the head padding.
+ *			This value shall be non-zero.
+ * @service_class:	Service class identifier for the datagram.
+ * @reserved:		Reserved bytes. Set to zero
+ */
+struct mux_adth_dg {
+	__le32 datagram_index;
+	__le16 datagram_length;
+	u8 service_class;
+	u8 reserved;
+};
+
+/**
+ * struct mux_qlth_ql - Structure of the queue level in the Aggregated
+ *			Datagram Queue Level Table Header.
+ * @nr_of_bytes:	Number of bytes available to transmit in the queue.
+ */
+struct mux_qlth_ql {
+	__le32 nr_of_bytes;
+};
+
+/**
+ * struct mux_qlth -    Structure of Aggregated Datagram Queue Level Table
+ *			Header.
+ * @signature:          Signature of the Queue Level Table Header
+ *                      Value: 0x48544C51 (ASCII characters: 'Q' 'L' 'T' 'H')
+ * @table_length:       Length (in bytes) of the datagram table. This length
+ *                      shall include the queue level table header size.
+ *                      Minimum value:0x10
+ * @if_id:              ID of the interface the queue levels in the table
+ *                      belong to.
+ * @reserved:           Reserved byte. Set to zero.
+ * @next_table_index:   Index (in bytes) to the next table in the buffer. Index
+ *                      shall count from the start of the block including the
+ *                      16-byte header. Value of zero indicates end of the list.
+ * @reserved2:          Reserved bytes. Set to zero
+ * @ql:                 Queue level table with variable length
+ */
+struct mux_qlth {
+	__le32 signature;
+	__le16 table_length;
+	u8 if_id;
+	u8 reserved;
+	__le32 next_table_index;
+	__le32 reserved2;
+	struct mux_qlth_ql ql;
+};
+
+/**
+ * struct mux_adb - Structure of State of a single UL data block.
+ * @dest_skb:		Current UL skb for the data block.
+ * @buf:		ADB memory
+ * @adgh:		ADGH pointer
+ * @qlth_skb:		QLTH pointer
+ * @next_table_index:	Pointer to next table index.
+ * @free_list:		List of alloc. ADB for the UL sess.
+ * @size:		Size of the ADB memory.
+ * @if_cnt:		Statistic counter
+ * @dg_cnt_total:	Datagram count total
+ * @payload_size:	Payload Size
+ * @dg:			Datagram table.
+ * @pp_qlt:		Pointers to hold Queue Level Tables of session
+ * @adbh:		ADBH pointer
+ * @qlt_updated:	Queue level table updated
+ * @dg_count:		Datagram count
+ */
 struct mux_adb {
-	struct sk_buff *dest_skb; /* Current UL skb for the data block. */
-	u8 *buf; /* ADB memory. */
-	struct mux_adgh *adgh; /* ADGH pointer */
-	struct sk_buff *qlth_skb; /* QLTH pointer */
-	u32 *next_table_index; /* Pointer to next table index. */
-	struct sk_buff_head free_list; /* List of alloc. ADB for the UL sess.*/
-	int size; /* Size of the ADB memory. */
-	u32 if_cnt; /* Statistic counter */
+	struct sk_buff *dest_skb;
+	u8 *buf;
+	struct mux_adgh *adgh;
+	struct sk_buff *qlth_skb;
+	u32 *next_table_index;
+	struct sk_buff_head free_list;
+	int size;
+	u32 if_cnt;
 	u32 dg_cnt_total;
 	u32 payload_size;
+	struct mux_adth_dg
+		dg[IPC_MEM_MUX_IP_SESSION_ENTRIES][IPC_MEM_MAX_UL_DG_ENTRIES];
+	struct mux_qlth *pp_qlt[IPC_MEM_MUX_IP_SESSION_ENTRIES];
+	struct mux_adbh *adbh;
+	u32 qlt_updated[IPC_MEM_MUX_IP_SESSION_ENTRIES];
+	u32 dg_count[IPC_MEM_MUX_IP_SESSION_ENTRIES];
 };
 
-/* Temporary ACB state. */
+/**
+ * struct mux_acb - Structure of Temporary ACB state.
+ * @skb:		Used UL skb.
+ * @if_id:		Session id.
+ * @buf_p:		Command buffer.
+ * @wanted_response:	Wanted Response
+ * @got_response:	Got response
+ * @cmd:		command
+ * @got_param:		Received command/response parameter
+ */
 struct mux_acb {
 	struct sk_buff *skb; /* Used UL skb. */
 	int if_id; /* Session id. */
+	u8 *buf_p;
 	u32 wanted_response;
 	u32 got_response;
 	u32 cmd;
@@ -241,6 +332,12 @@ struct mux_acb {
  * @wwan_q_offset:	This will hold the offset of the given instance
  *			Useful while passing or receiving packets from
  *			wwan/imem layer.
+ * @adb_finish_timer:	Timer for forcefully finishing the ADB
+ * @acb_tx_sequence_nr: Sequence number for the ACB header.
+ * @params:		user configurable parameters
+ * @adb_tx_sequence_nr: Sequence number for ADB header
+ * @acc_adb_size:       Statistic data for logging
+ * @acc_payload_size:   Statistic data for logging
  * @initialized:	MUX object is initialized
  * @ev_mux_net_transmit_pending:
  *			0 means inform the IPC tasklet to pass the
@@ -269,10 +366,16 @@ struct iosm_mux {
 	long long ul_data_pend_bytes;
 	struct mux_acb acb;
 	int wwan_q_offset;
+	struct hrtimer adb_finish_timer;
+	u16 acb_tx_sequence_nr;
+	struct ipc_params *params;
+	u16 adb_tx_sequence_nr;
+	unsigned long long acc_adb_size;
+	unsigned long long acc_payload_size;
 	u8 initialized:1,
 	   ev_mux_net_transmit_pending:1,
-	   adb_prep_ongoing:1;
-};
+	   adb_prep_ongoing;
+} __packed;
 
 /* MUX configuration structure */
 struct ipc_mux_config {