drivers/net/ipa/gsi.h - linux - Git at Google

 /* SPDX-License-Identifier: GPL-2.0 */

 /* Copyright (c) 2015-2018, The Linux Foundation. All rights reserved.
  * Copyright (C) 2018-2024 Linaro Ltd.
  */
 #ifndef _GSI_H_
 #define _GSI_H_

 #include <linux/completion.h>
 #include <linux/mutex.h>
 #include <linux/netdevice.h>
 #include <linux/types.h>

 #include "ipa_version.h"

 /* Maximum number of channels and event rings supported by the driver */
 #define GSI_CHANNEL_COUNT_MAX	28
 #define GSI_EVT_RING_COUNT_MAX	28

 /* Maximum TLV FIFO size for a channel; 64 here is arbitrary (and high) */
 #define GSI_TLV_MAX		64

 struct device;
 struct platform_device;

 struct gsi;
 struct gsi_trans;
 struct ipa_gsi_endpoint_data;

 struct gsi_ring {
 	void *virt;			/* ring array base address */
 	dma_addr_t addr;		/* primarily low 32 bits used */
 	u32 count;			/* number of elements in ring */

 	/* The ring index value indicates the next "open" entry in the ring.
 	 *
 	 * A channel ring consists of TRE entries filled by the AP and passed
 	 * to the hardware for processing.  For a channel ring, the ring index
 	 * identifies the next unused entry to be filled by the AP.  In this
 	 * case the initial value is assumed by hardware to be 0.
 	 *
 	 * An event ring consists of event structures filled by the hardware
 	 * and passed to the AP.  For event rings, the ring index identifies
 	 * the next ring entry that is not known to have been filled by the
 	 * hardware.  The initial value used is arbitrary (so we use 0).
 	 */
 	u32 index;
 };

 /* Transactions use several resources that can be allocated dynamically
  * but taken from a fixed-size pool.  The number of elements required for
  * the pool is limited by the total number of TREs that can be outstanding.
  *
  * If sufficient TREs are available to reserve for a transaction,
  * allocation from these pools is guaranteed to succeed.  Furthermore,
  * these resources are implicitly freed whenever the TREs in the
  * transaction they're associated with are released.
  *
  * The result of a pool allocation of multiple elements is always
  * contiguous.
  */
 struct gsi_trans_pool {
 	void *base;			/* base address of element pool */
 	u32 count;			/* # elements in the pool */
 	u32 free;			/* next free element in pool (modulo) */
 	u32 size;			/* size (bytes) of an element */
 	u32 max_alloc;			/* max allocation request */
 	dma_addr_t addr;		/* DMA address if DMA pool (or 0) */
 };

 struct gsi_trans_info {
 	atomic_t tre_avail;		/* TREs available for allocation */

 	u16 free_id;			/* first free trans in array */
 	u16 allocated_id;		/* first allocated transaction */
 	u16 committed_id;		/* first committed transaction */
 	u16 pending_id;			/* first pending transaction */
 	u16 completed_id;		/* first completed transaction */
 	u16 polled_id;			/* first polled transaction */
 	struct gsi_trans *trans;	/* transaction array */
 	struct gsi_trans **map;		/* TRE -> transaction map */

 	struct gsi_trans_pool sg_pool;	/* scatterlist pool */
 	struct gsi_trans_pool cmd_pool;	/* command payload DMA pool */
 };

 /* Hardware values signifying the state of a channel */
 enum gsi_channel_state {
 	GSI_CHANNEL_STATE_NOT_ALLOCATED		= 0x0,
 	GSI_CHANNEL_STATE_ALLOCATED		= 0x1,
 	GSI_CHANNEL_STATE_STARTED		= 0x2,
 	GSI_CHANNEL_STATE_STOPPED		= 0x3,
 	GSI_CHANNEL_STATE_STOP_IN_PROC		= 0x4,
 	GSI_CHANNEL_STATE_FLOW_CONTROLLED	= 0x5,	/* IPA v4.2-v4.9 */
 	GSI_CHANNEL_STATE_ERROR			= 0xf,
 };

 /* We only care about channels between IPA and AP */
 struct gsi_channel {
 	struct gsi *gsi;
 	bool toward_ipa;
 	bool command;			/* AP command TX channel or not */

 	u8 trans_tre_max;		/* max TREs in a transaction */
 	u16 tre_count;
 	u16 event_count;

 	struct gsi_ring tre_ring;
 	u32 evt_ring_id;

 	/* The following counts are used only for TX endpoints */
 	u64 byte_count;			/* total # bytes transferred */
 	u64 trans_count;		/* total # transactions */
 	u64 queued_byte_count;		/* last reported queued byte count */
 	u64 queued_trans_count;		/* ...and queued trans count */
 	u64 compl_byte_count;		/* last reported completed byte count */
 	u64 compl_trans_count;		/* ...and completed trans count */

 	struct gsi_trans_info trans_info;

 	struct napi_struct napi;
 };

 /* Hardware values signifying the state of an event ring */
 enum gsi_evt_ring_state {
 	GSI_EVT_RING_STATE_NOT_ALLOCATED	= 0x0,
 	GSI_EVT_RING_STATE_ALLOCATED		= 0x1,
 	GSI_EVT_RING_STATE_ERROR		= 0xf,
 };

 struct gsi_evt_ring {
 	struct gsi_channel *channel;
 	struct gsi_ring ring;
 };

 struct gsi {
 	struct device *dev;		/* Same as IPA device */
 	enum ipa_version version;
 	void __iomem *virt;		/* I/O mapped registers */
 	const struct regs *regs;

 	u32 irq;
 	u32 channel_count;
 	u32 evt_ring_count;
 	u32 event_bitmap;		/* allocated event rings */
 	u32 modem_channel_bitmap;	/* modem channels to allocate */
 	u32 type_enabled_bitmap;	/* GSI IRQ types enabled */
 	u32 ieob_enabled_bitmap;	/* IEOB IRQ enabled (event rings) */
 	int result;			/* Negative errno (generic commands) */
 	struct completion completion;	/* Signals GSI command completion */
 	struct mutex mutex;		/* protects commands, programming */
 	struct gsi_channel channel[GSI_CHANNEL_COUNT_MAX];
 	struct gsi_evt_ring evt_ring[GSI_EVT_RING_COUNT_MAX];
 	struct net_device *dummy_dev;	/* needed for NAPI */
 };

 /**
  * gsi_setup() - Set up the GSI subsystem
  * @gsi:	Address of GSI structure embedded in an IPA structure
  *
  * Return:	0 if successful, or a negative error code
  *
  * Performs initialization that must wait until the GSI hardware is
  * ready (including firmware loaded).
  */
 int gsi_setup(struct gsi *gsi);

 /**
  * gsi_teardown() - Tear down GSI subsystem
  * @gsi:	GSI address previously passed to a successful gsi_setup() call
  */
 void gsi_teardown(struct gsi *gsi);

 /**
  * gsi_channel_tre_max() - Channel maximum number of in-flight TREs
  * @gsi:	GSI pointer
  * @channel_id:	Channel whose limit is to be returned
  *
  * Return:	 The maximum number of TREs outstanding on the channel
  */
 u32 gsi_channel_tre_max(struct gsi *gsi, u32 channel_id);

 /**
  * gsi_channel_start() - Start an allocated GSI channel
  * @gsi:	GSI pointer
  * @channel_id:	Channel to start
  *
  * Return:	0 if successful, or a negative error code
  */
 int gsi_channel_start(struct gsi *gsi, u32 channel_id);

 /**
  * gsi_channel_stop() - Stop a started GSI channel
  * @gsi:	GSI pointer returned by gsi_setup()
  * @channel_id:	Channel to stop
  *
  * Return:	0 if successful, or a negative error code
  */
 int gsi_channel_stop(struct gsi *gsi, u32 channel_id);

 /**
  * gsi_modem_channel_flow_control() - Set channel flow control state (IPA v4.2+)
  * @gsi:	GSI pointer returned by gsi_setup()
  * @channel_id:	Modem TX channel to control
  * @enable:	Whether to enable flow control (i.e., prevent flow)
  */
 void gsi_modem_channel_flow_control(struct gsi *gsi, u32 channel_id,
 				    bool enable);

 /**
  * gsi_channel_reset() - Reset an allocated GSI channel
  * @gsi:	GSI pointer
  * @channel_id:	Channel to be reset
  * @doorbell:	Whether to (possibly) enable the doorbell engine
  *
  * Reset a channel and reconfigure it.  The @doorbell flag indicates
  * that the doorbell engine should be enabled if needed.
  *
  * GSI hardware relinquishes ownership of all pending receive buffer
  * transactions and they will complete with their cancelled flag set.
  */
 void gsi_channel_reset(struct gsi *gsi, u32 channel_id, bool doorbell);

 /**
  * gsi_suspend() - Prepare the GSI subsystem for suspend
  * @gsi:	GSI pointer
  */
 void gsi_suspend(struct gsi *gsi);

 /**
  * gsi_resume() - Resume the GSI subsystem following suspend
  * @gsi:	GSI pointer
  */
 void gsi_resume(struct gsi *gsi);

 /**
  * gsi_channel_suspend() - Suspend a GSI channel
  * @gsi:	GSI pointer
  * @channel_id:	Channel to suspend
  *
  * For IPA v4.0+, suspend is implemented by stopping the channel.
  */
 int gsi_channel_suspend(struct gsi *gsi, u32 channel_id);

 /**
  * gsi_channel_resume() - Resume a suspended GSI channel
  * @gsi:	GSI pointer
  * @channel_id:	Channel to resume
  *
  * For IPA v4.0+, the stopped channel is started again.
  */
 int gsi_channel_resume(struct gsi *gsi, u32 channel_id);

 /**
  * gsi_init() - Initialize the GSI subsystem
  * @gsi:	Address of GSI structure embedded in an IPA structure
  * @pdev:	IPA platform device
  * @version:	IPA hardware version (implies GSI version)
  * @count:	Number of entries in the configuration data array
  * @data:	Endpoint and channel configuration data
  *
  * Return:	0 if successful, or a negative error code
  *
  * Early stage initialization of the GSI subsystem, performing tasks
  * that can be done before the GSI hardware is ready to use.
  */
 int gsi_init(struct gsi *gsi, struct platform_device *pdev,
 	     enum ipa_version version, u32 count,
 	     const struct ipa_gsi_endpoint_data *data);

 /**
  * gsi_exit() - Exit the GSI subsystem
  * @gsi:	GSI address previously passed to a successful gsi_init() call
  */
 void gsi_exit(struct gsi *gsi);

 #endif /* _GSI_H_ */
	/* SPDX-License-Identifier: GPL-2.0 */

	/* Copyright (c) 2015-2018, The Linux Foundation. All rights reserved.
	* Copyright (C) 2018-2024 Linaro Ltd.
	*/
	#ifndef _GSI_H_
	#define _GSI_H_

	#include <linux/completion.h>
	#include <linux/mutex.h>
	#include <linux/netdevice.h>
	#include <linux/types.h>

	#include "ipa_version.h"

	/* Maximum number of channels and event rings supported by the driver */
	#define GSI_CHANNEL_COUNT_MAX 28
	#define GSI_EVT_RING_COUNT_MAX 28

	/* Maximum TLV FIFO size for a channel; 64 here is arbitrary (and high) */
	#define GSI_TLV_MAX 64

	struct device;
	struct platform_device;

	struct gsi;
	struct gsi_trans;
	struct ipa_gsi_endpoint_data;

	struct gsi_ring {
	void virt; / ring array base address */
	dma_addr_t addr; /* primarily low 32 bits used */
	u32 count; /* number of elements in ring */

	/* The ring index value indicates the next "open" entry in the ring.
	*
	* A channel ring consists of TRE entries filled by the AP and passed
	* to the hardware for processing. For a channel ring, the ring index
	* identifies the next unused entry to be filled by the AP. In this
	* case the initial value is assumed by hardware to be 0.
	*
	* An event ring consists of event structures filled by the hardware
	* and passed to the AP. For event rings, the ring index identifies
	* the next ring entry that is not known to have been filled by the
	* hardware. The initial value used is arbitrary (so we use 0).
	*/
	u32 index;
	};

	/* Transactions use several resources that can be allocated dynamically
	* but taken from a fixed-size pool. The number of elements required for
	* the pool is limited by the total number of TREs that can be outstanding.
	*
	* If sufficient TREs are available to reserve for a transaction,
	* allocation from these pools is guaranteed to succeed. Furthermore,
	* these resources are implicitly freed whenever the TREs in the
	* transaction they're associated with are released.
	*
	* The result of a pool allocation of multiple elements is always
	* contiguous.
	*/
	struct gsi_trans_pool {
	void base; / base address of element pool */
	u32 count; /* # elements in the pool */
	u32 free; /* next free element in pool (modulo) */
	u32 size; /* size (bytes) of an element */
	u32 max_alloc; /* max allocation request */
	dma_addr_t addr; /* DMA address if DMA pool (or 0) */
	};

	struct gsi_trans_info {
	atomic_t tre_avail; /* TREs available for allocation */

	u16 free_id; /* first free trans in array */
	u16 allocated_id; /* first allocated transaction */
	u16 committed_id; /* first committed transaction */
	u16 pending_id; /* first pending transaction */
	u16 completed_id; /* first completed transaction */
	u16 polled_id; /* first polled transaction */
	struct gsi_trans trans; / transaction array */
	struct gsi_trans *map; / TRE -> transaction map */

	struct gsi_trans_pool sg_pool; /* scatterlist pool */
	struct gsi_trans_pool cmd_pool; /* command payload DMA pool */
	};

	/* Hardware values signifying the state of a channel */
	enum gsi_channel_state {
	GSI_CHANNEL_STATE_NOT_ALLOCATED = 0x0,
	GSI_CHANNEL_STATE_ALLOCATED = 0x1,
	GSI_CHANNEL_STATE_STARTED = 0x2,
	GSI_CHANNEL_STATE_STOPPED = 0x3,
	GSI_CHANNEL_STATE_STOP_IN_PROC = 0x4,
	GSI_CHANNEL_STATE_FLOW_CONTROLLED = 0x5, /* IPA v4.2-v4.9 */
	GSI_CHANNEL_STATE_ERROR = 0xf,
	};

	/* We only care about channels between IPA and AP */
	struct gsi_channel {
	struct gsi *gsi;
	bool toward_ipa;
	bool command; /* AP command TX channel or not */

	u8 trans_tre_max; /* max TREs in a transaction */
	u16 tre_count;
	u16 event_count;

	struct gsi_ring tre_ring;
	u32 evt_ring_id;

	/* The following counts are used only for TX endpoints */
	u64 byte_count; /* total # bytes transferred */
	u64 trans_count; /* total # transactions */
	u64 queued_byte_count; /* last reported queued byte count */
	u64 queued_trans_count; /* ...and queued trans count */
	u64 compl_byte_count; /* last reported completed byte count */
	u64 compl_trans_count; /* ...and completed trans count */

	struct gsi_trans_info trans_info;

	struct napi_struct napi;
	};

	/* Hardware values signifying the state of an event ring */
	enum gsi_evt_ring_state {
	GSI_EVT_RING_STATE_NOT_ALLOCATED = 0x0,
	GSI_EVT_RING_STATE_ALLOCATED = 0x1,
	GSI_EVT_RING_STATE_ERROR = 0xf,
	};

	struct gsi_evt_ring {
	struct gsi_channel *channel;
	struct gsi_ring ring;
	};

	struct gsi {
	struct device dev; / Same as IPA device */
	enum ipa_version version;
	void __iomem virt; / I/O mapped registers */
	const struct regs *regs;

	u32 irq;
	u32 channel_count;
	u32 evt_ring_count;
	u32 event_bitmap; /* allocated event rings */
	u32 modem_channel_bitmap; /* modem channels to allocate */
	u32 type_enabled_bitmap; /* GSI IRQ types enabled */
	u32 ieob_enabled_bitmap; /* IEOB IRQ enabled (event rings) */
	int result; /* Negative errno (generic commands) */
	struct completion completion; /* Signals GSI command completion */
	struct mutex mutex; /* protects commands, programming */
	struct gsi_channel channel[GSI_CHANNEL_COUNT_MAX];
	struct gsi_evt_ring evt_ring[GSI_EVT_RING_COUNT_MAX];
	struct net_device dummy_dev; / needed for NAPI */
	};

	/**
	* gsi_setup() - Set up the GSI subsystem
	* @gsi: Address of GSI structure embedded in an IPA structure
	*
	* Return: 0 if successful, or a negative error code
	*
	* Performs initialization that must wait until the GSI hardware is
	* ready (including firmware loaded).
	*/
	int gsi_setup(struct gsi *gsi);

	/**
	* gsi_teardown() - Tear down GSI subsystem
	* @gsi: GSI address previously passed to a successful gsi_setup() call
	*/
	void gsi_teardown(struct gsi *gsi);

	/**
	* gsi_channel_tre_max() - Channel maximum number of in-flight TREs
	* @gsi: GSI pointer
	* @channel_id: Channel whose limit is to be returned
	*
	* Return: The maximum number of TREs outstanding on the channel
	*/
	u32 gsi_channel_tre_max(struct gsi *gsi, u32 channel_id);

	/**
	* gsi_channel_start() - Start an allocated GSI channel
	* @gsi: GSI pointer
	* @channel_id: Channel to start
	*
	* Return: 0 if successful, or a negative error code
	*/
	int gsi_channel_start(struct gsi *gsi, u32 channel_id);

	/**
	* gsi_channel_stop() - Stop a started GSI channel
	* @gsi: GSI pointer returned by gsi_setup()
	* @channel_id: Channel to stop
	*
	* Return: 0 if successful, or a negative error code
	*/
	int gsi_channel_stop(struct gsi *gsi, u32 channel_id);

	/**
	* gsi_modem_channel_flow_control() - Set channel flow control state (IPA v4.2+)
	* @gsi: GSI pointer returned by gsi_setup()
	* @channel_id: Modem TX channel to control
	* @enable: Whether to enable flow control (i.e., prevent flow)
	*/
	void gsi_modem_channel_flow_control(struct gsi *gsi, u32 channel_id,
	bool enable);

	/**
	* gsi_channel_reset() - Reset an allocated GSI channel
	* @gsi: GSI pointer
	* @channel_id: Channel to be reset
	* @doorbell: Whether to (possibly) enable the doorbell engine
	*
	* Reset a channel and reconfigure it. The @doorbell flag indicates
	* that the doorbell engine should be enabled if needed.
	*
	* GSI hardware relinquishes ownership of all pending receive buffer
	* transactions and they will complete with their cancelled flag set.
	*/
	void gsi_channel_reset(struct gsi *gsi, u32 channel_id, bool doorbell);

	/**
	* gsi_suspend() - Prepare the GSI subsystem for suspend
	* @gsi: GSI pointer
	*/
	void gsi_suspend(struct gsi *gsi);

	/**
	* gsi_resume() - Resume the GSI subsystem following suspend
	* @gsi: GSI pointer
	*/
	void gsi_resume(struct gsi *gsi);

	/**
	* gsi_channel_suspend() - Suspend a GSI channel
	* @gsi: GSI pointer
	* @channel_id: Channel to suspend
	*
	* For IPA v4.0+, suspend is implemented by stopping the channel.
	*/
	int gsi_channel_suspend(struct gsi *gsi, u32 channel_id);

	/**
	* gsi_channel_resume() - Resume a suspended GSI channel
	* @gsi: GSI pointer
	* @channel_id: Channel to resume
	*
	* For IPA v4.0+, the stopped channel is started again.
	*/
	int gsi_channel_resume(struct gsi *gsi, u32 channel_id);

	/**
	* gsi_init() - Initialize the GSI subsystem
	* @gsi: Address of GSI structure embedded in an IPA structure
	* @pdev: IPA platform device
	* @version: IPA hardware version (implies GSI version)
	* @count: Number of entries in the configuration data array
	* @data: Endpoint and channel configuration data
	*
	* Return: 0 if successful, or a negative error code
	*
	* Early stage initialization of the GSI subsystem, performing tasks
	* that can be done before the GSI hardware is ready to use.
	*/
	int gsi_init(struct gsi gsi, struct platform_device pdev,
	enum ipa_version version, u32 count,
	const struct ipa_gsi_endpoint_data *data);

	/**
	* gsi_exit() - Exit the GSI subsystem
	* @gsi: GSI address previously passed to a successful gsi_init() call
	*/
	void gsi_exit(struct gsi *gsi);

	#endif /* _GSI_H_ */