path: root/drivers/misc/mei/mei_dev.h

/* SPDX-License-Identifier: GPL-2.0 */
/*
 * Copyright (c) 2003-2019, Intel Corporation. All rights reserved.
 * Intel Management Engine Interface (Intel MEI) Linux driver
 */

#ifndef _MEI_DEV_H_
#define _MEI_DEV_H_

#include <linux/types.h>
#include <linux/cdev.h>
#include <linux/poll.h>
#include <linux/mei.h>
#include <linux/mei_cl_bus.h>

#include "hw.h"
#include "hbm.h"

#define MEI_SLOT_SIZE             sizeof(u32)
#define MEI_RD_MSG_BUF_SIZE       (128 * MEI_SLOT_SIZE)

/*
 * Number of Maximum MEI Clients
 */
#define MEI_CLIENTS_MAX 256

/*
 * maximum number of consecutive resets
 */
#define MEI_MAX_CONSEC_RESET  3

/*
 * Number of File descriptors/handles
 * that can be opened to the driver.
 *
 * Limit to 255: 256 Total Clients
 * minus internal client for MEI Bus Messages
 */
#define  MEI_MAX_OPEN_HANDLE_COUNT (MEI_CLIENTS_MAX - 1)

/* File state */
enum file_state {
	MEI_FILE_UNINITIALIZED = 0,
	MEI_FILE_INITIALIZING,
	MEI_FILE_CONNECTING,
	MEI_FILE_CONNECTED,
	MEI_FILE_DISCONNECTING,
	MEI_FILE_DISCONNECT_REPLY,
	MEI_FILE_DISCONNECT_REQUIRED,
	MEI_FILE_DISCONNECTED,
};

/* MEI device states */
enum mei_dev_state {
	MEI_DEV_INITIALIZING = 0,
	MEI_DEV_INIT_CLIENTS,
	MEI_DEV_ENABLED,
	MEI_DEV_RESETTING,
	MEI_DEV_DISABLED,
	MEI_DEV_POWER_DOWN,
	MEI_DEV_POWER_UP
};

const char *mei_dev_state_str(int state);

enum mei_file_transaction_states {
	MEI_IDLE,
	MEI_WRITING,
	MEI_WRITE_COMPLETE,
};

/**
 * enum mei_cb_file_ops  - file operation associated with the callback
 * @MEI_FOP_READ:       read
 * @MEI_FOP_WRITE:      write
 * @MEI_FOP_CONNECT:    connect
 * @MEI_FOP_DISCONNECT: disconnect
 * @MEI_FOP_DISCONNECT_RSP: disconnect response
 * @MEI_FOP_NOTIFY_START:   start notification
 * @MEI_FOP_NOTIFY_STOP:    stop notification
 */
enum mei_cb_file_ops {
	MEI_FOP_READ = 0,
	MEI_FOP_WRITE,
	MEI_FOP_CONNECT,
	MEI_FOP_DISCONNECT,
	MEI_FOP_DISCONNECT_RSP,
	MEI_FOP_NOTIFY_START,
	MEI_FOP_NOTIFY_STOP,
};

/**
 * enum mei_cl_io_mode - io mode between driver and fw
 *
 * @MEI_CL_IO_TX_BLOCKING: send is blocking
 * @MEI_CL_IO_TX_INTERNAL: internal communication between driver and FW
 *
 * @MEI_CL_IO_RX_NONBLOCK: recv is non-blocking
 */
enum mei_cl_io_mode {
	MEI_CL_IO_TX_BLOCKING = BIT(0),
	MEI_CL_IO_TX_INTERNAL = BIT(1),

	MEI_CL_IO_RX_NONBLOCK = BIT(2),
};

/*
 * Intel MEI message data struct
 */
struct mei_msg_data {
	size_t size;
	unsigned char *data;
};

/**
 * struct mei_dma_dscr - dma address descriptor
 *
 * @vaddr: dma buffer virtual address
 * @daddr: dma buffer physical address
 * @size : dma buffer size
 */
struct mei_dma_dscr {
	void *vaddr;
	dma_addr_t daddr;
	size_t size;
};

/* Maximum number of processed FW status registers */
#define MEI_FW_STATUS_MAX 6
/* Minimal  buffer for FW status string (8 bytes in dw + space or '\0') */
#define MEI_FW_STATUS_STR_SZ (MEI_FW_STATUS_MAX * (8 + 1))


/*
 * struct mei_fw_status - storage of FW status data
 *
 * @count: number of actually available elements in array
 * @status: FW status registers
 */
struct mei_fw_status {
	int count;
	u32 status[MEI_FW_STATUS_MAX];
};

/**
 * struct mei_me_client - representation of me (fw) client
 *
 * @list: link in me client list
 * @refcnt: struct reference count
 * @props: client properties
 * @client_id: me client id
 * @tx_flow_ctrl_creds: flow control credits
 * @connect_count: number connections to this client
 * @bus_added: added to bus
 */
struct mei_me_client {
	struct list_head list;
	struct kref refcnt;
	struct mei_client_properties props;
	u8 client_id;
	u8 tx_flow_ctrl_creds;
	u8 connect_count;
	u8 bus_added;
};


struct mei_cl;

/**
 * struct mei_cl_cb - file operation callback structure
 *
 * @list: link in callback queue
 * @cl: file client who is running this operation
 * @fop_type: file operation type
 * @buf: buffer for data associated with the callback
 * @buf_idx: last read index
 * @fp: pointer to file structure
 * @status: io status of the cb
 * @internal: communication between driver and FW flag
 * @blocking: transmission blocking mode
 */
struct mei_cl_cb {
	struct list_head list;
	struct mei_cl *cl;
	enum mei_cb_file_ops fop_type;
	struct mei_msg_data buf;
	size_t buf_idx;
	const struct file *fp;
	int status;
	u32 internal:1;
	u32 blocking:1;
};

/**
 * struct mei_cl - me client host representation
 *    carried in file->private_data
 *
 * @link: link in the clients list
 * @dev: mei parent device
 * @state: file operation state
 * @tx_wait: wait queue for tx completion
 * @rx_wait: wait queue for rx completion
 * @wait:  wait queue for management operation
 * @ev_wait: notification wait queue
 * @ev_async: event async notification
 * @status: connection status
 * @me_cl: fw client connected
 * @fp: file associated with client
 * @host_client_id: host id
 * @tx_flow_ctrl_creds: transmit flow credentials
 * @rx_flow_ctrl_creds: receive flow credentials
 * @timer_count:  watchdog timer for operation completion
 * @notify_en: notification - enabled/disabled
 * @notify_ev: pending notification event
 * @tx_cb_queued: number of tx callbacks in queue
 * @writing_state: state of the tx
 * @rd_pending: pending read credits
 * @rd_completed: completed read
 *
 * @cldev: device on the mei client bus
 */
struct mei_cl {
	struct list_head link;
	struct mei_device *dev;
	enum file_state state;
	wait_queue_head_t tx_wait;
	wait_queue_head_t rx_wait;
	wait_queue_head_t wait;
	wait_queue_head_t ev_wait;
	struct fasync_struct *ev_async;
	int status;
	struct mei_me_client *me_cl;
	const struct file *fp;
	u8 host_client_id;
	u8 tx_flow_ctrl_creds;
	u8 rx_flow_ctrl_creds;
	u8 timer_count;
	u8 notify_en;
	u8 notify_ev;
	u8 tx_cb_queued;
	enum mei_file_transaction_states writing_state;
	struct list_head rd_pending;
	struct list_head rd_completed;

	struct mei_cl_device *cldev;
};

#define MEI_TX_QUEUE_LIMIT_DEFAULT 50
#define MEI_TX_QUEUE_LIMIT_MAX 255
#define MEI_TX_QUEUE_LIMIT_MIN 30

/**
 * struct mei_hw_ops - hw specific ops
 *
 * @host_is_ready    : query for host readiness
 *
 * @hw_is_ready      : query if hw is ready
 * @hw_reset         : reset hw
 * @hw_start         : start hw after reset
 * @hw_config        : configure hw
 *
 * @fw_status        : get fw status registers
 * @pg_state         : power gating state of the device
 * @pg_in_transition : is device now in pg transition
 * @pg_is_enabled    : is power gating enabled
 *
 * @intr_clear       : clear pending interrupts
 * @intr_enable      : enable interrupts
 * @intr_disable     : disable interrupts
 * @synchronize_irq  : synchronize irqs
 *
 * @hbuf_free_slots  : query for write buffer empty slots
 * @hbuf_is_ready    : query if write buffer is empty
 * @hbuf_depth       : query for write buffer depth
 *
 * @write            : write a message to FW
 *
 * @rdbuf_full_slots : query how many slots are filled
 *
 * @read_hdr         : get first 4 bytes (header)
 * @read             : read a buffer from the FW
 */
struct mei_hw_ops {

	bool (*host_is_ready)(struct mei_device *dev);

	bool (*hw_is_ready)(struct mei_device *dev);
	int (*hw_reset)(struct mei_device *dev, bool enable);
	int (*hw_start)(struct mei_device *dev);
	int (*hw_config)(struct mei_device *dev);

	int (*fw_status)(struct mei_device *dev, struct mei_fw_status *fw_sts);
	enum mei_pg_state (*pg_state)(struct mei_device *dev);
	bool (*pg_in_transition)(struct mei_device *dev);
	bool (*pg_is_enabled)(struct mei_device *dev);

	void (*intr_clear)(struct mei_device *dev);
	void (*intr_enable)(struct mei_device *dev);
	void (*intr_disable)(struct mei_device *dev);
	void (*synchronize_irq)(struct mei_device *dev);

	int (*hbuf_free_slots)(struct mei_device *dev);
	bool (*hbuf_is_ready)(struct mei_device *dev);
	u32 (*hbuf_depth)(const struct mei_device *dev);
	int (*write)(struct mei_device *dev,
		     const void *hdr, size_t hdr_len,
		     const void *data, size_t data_len);

	int (*rdbuf_full_slots)(struct mei_device *dev);

	u32 (*read_hdr)(const struct mei_device *dev);
	int (*read)(struct mei_device *dev,