drivers/misc/mei/init.c - manifest_repos/salami - Git at Google

 /*
  *
  * Intel Management Engine Interface (Intel MEI) Linux driver
  * Copyright (c) 2003-2012, Intel Corporation.
  *
  * This program is free software; you can redistribute it and/or modify it
  * under the terms and conditions of the GNU General Public License,
  * version 2, as published by the Free Software Foundation.
  *
  * This program is distributed in the hope it will be useful, but WITHOUT
  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
  * more details.
  *
  */

 #include <linux/pci.h>
 #include <linux/sched.h>
 #include <linux/wait.h>
 #include <linux/delay.h>

 #include "mei_dev.h"
 #include "hw.h"
 #include "interface.h"
 #include <linux/mei.h>

 const char *mei_dev_state_str(int state)
 {
 #define MEI_DEV_STATE(state) case MEI_DEV_##state: return #state
 	switch (state) {
 	MEI_DEV_STATE(INITIALIZING);
 	MEI_DEV_STATE(INIT_CLIENTS);
 	MEI_DEV_STATE(ENABLED);
 	MEI_DEV_STATE(RESETING);
 	MEI_DEV_STATE(DISABLED);
 	MEI_DEV_STATE(RECOVERING_FROM_RESET);
 	MEI_DEV_STATE(POWER_DOWN);
 	MEI_DEV_STATE(POWER_UP);
 	default:
 		return "unkown";
 	}
 #undef MEI_DEV_STATE
 }


 /**
  * mei_io_list_flush - removes list entry belonging to cl.
  *
  * @list:  An instance of our list structure
  * @cl: private data of the file object
  */
 void mei_io_list_flush(struct mei_cl_cb *list, struct mei_cl *cl)
 {
 	struct mei_cl_cb *pos;
 	struct mei_cl_cb *next;

 	list_for_each_entry_safe(pos, next, &list->list, list) {
 		if (pos->cl) {
 			if (mei_cl_cmp_id(cl, pos->cl))
 				list_del(&pos->list);
 		}
 	}
 }
 /**
  * mei_cl_flush_queues - flushes queue lists belonging to cl.
  *
  * @dev: the device structure
  * @cl: private data of the file object
  */
 int mei_cl_flush_queues(struct mei_cl *cl)
 {
 	if (!cl || !cl->dev)
 		return -EINVAL;

 	dev_dbg(&cl->dev->pdev->dev, "remove list entry belonging to cl\n");
 	mei_io_list_flush(&cl->dev->read_list, cl);
 	mei_io_list_flush(&cl->dev->write_list, cl);
 	mei_io_list_flush(&cl->dev->write_waiting_list, cl);
 	mei_io_list_flush(&cl->dev->ctrl_wr_list, cl);
 	mei_io_list_flush(&cl->dev->ctrl_rd_list, cl);
 	mei_io_list_flush(&cl->dev->amthif_cmd_list, cl);
 	mei_io_list_flush(&cl->dev->amthif_rd_complete_list, cl);
 	return 0;
 }


 /**
  * init_mei_device - allocates and initializes the mei device structure
  *
  * @pdev: The pci device structure
  *
  * returns The mei_device_device pointer on success, NULL on failure.
  */
 struct mei_device *mei_device_init(struct pci_dev *pdev)
 {
 	struct mei_device *dev;

 	dev = kzalloc(sizeof(struct mei_device), GFP_KERNEL);
 	if (!dev)
 		return NULL;

 	/* setup our list array */
 	INIT_LIST_HEAD(&dev->file_list);
 	INIT_LIST_HEAD(&dev->wd_cl.link);
 	INIT_LIST_HEAD(&dev->iamthif_cl.link);
 	mutex_init(&dev->device_lock);
 	init_waitqueue_head(&dev->wait_recvd_msg);
 	init_waitqueue_head(&dev->wait_stop_wd);
 	dev->dev_state = MEI_DEV_INITIALIZING;
 	dev->iamthif_state = MEI_IAMTHIF_IDLE;

 	mei_io_list_init(&dev->read_list);
 	mei_io_list_init(&dev->write_list);
 	mei_io_list_init(&dev->write_waiting_list);
 	mei_io_list_init(&dev->ctrl_wr_list);
 	mei_io_list_init(&dev->ctrl_rd_list);
 	mei_io_list_init(&dev->amthif_cmd_list);
 	mei_io_list_init(&dev->amthif_rd_complete_list);
 	dev->pdev = pdev;
 	return dev;
 }

 /**
  * mei_hw_init - initializes host and fw to start work.
  *
  * @dev: the device structure
  *
  * returns 0 on success, <0 on failure.
  */
 int mei_hw_init(struct mei_device *dev)
 {
 	int err = 0;
 	int ret;

 	mutex_lock(&dev->device_lock);

 	dev->host_hw_state = mei_hcsr_read(dev);
 	dev->me_hw_state = mei_mecsr_read(dev);
 	dev_dbg(&dev->pdev->dev, "host_hw_state = 0x%08x, mestate = 0x%08x.\n",
 	    dev->host_hw_state, dev->me_hw_state);

 	/* acknowledge interrupt and stop interupts */
 	if ((dev->host_hw_state & H_IS) == H_IS)
 		mei_reg_write(dev, H_CSR, dev->host_hw_state);

 	/* Doesn't change in runtime */
 	dev->hbuf_depth = (dev->host_hw_state & H_CBD) >> 24;

 	dev->recvd_msg = false;
 	dev_dbg(&dev->pdev->dev, "reset in start the mei device.\n");

 	mei_reset(dev, 1);

 	dev_dbg(&dev->pdev->dev, "host_hw_state = 0x%08x, me_hw_state = 0x%08x.\n",
 	    dev->host_hw_state, dev->me_hw_state);

 	/* wait for ME to turn on ME_RDY */
 	if (!dev->recvd_msg) {
 		mutex_unlock(&dev->device_lock);
 		err = wait_event_interruptible_timeout(dev->wait_recvd_msg,
 			dev->recvd_msg,
 			mei_secs_to_jiffies(MEI_INTEROP_TIMEOUT));
 		mutex_lock(&dev->device_lock);
 	}

 	if (err <= 0 && !dev->recvd_msg) {
 		dev->dev_state = MEI_DEV_DISABLED;
 		dev_dbg(&dev->pdev->dev,
 			"wait_event_interruptible_timeout failed"
 			"on wait for ME to turn on ME_RDY.\n");
 		ret = -ENODEV;
 		goto out;
 	}

 	if (!(((dev->host_hw_state & H_RDY) == H_RDY) &&
 	      ((dev->me_hw_state & ME_RDY_HRA) == ME_RDY_HRA))) {
 		dev->dev_state = MEI_DEV_DISABLED;
 		dev_dbg(&dev->pdev->dev,
 			"host_hw_state = 0x%08x, me_hw_state = 0x%08x.\n",
 			dev->host_hw_state, dev->me_hw_state);

 		if (!(dev->host_hw_state & H_RDY))
 			dev_dbg(&dev->pdev->dev, "host turn off H_RDY.\n");

 		if (!(dev->me_hw_state & ME_RDY_HRA))
 			dev_dbg(&dev->pdev->dev, "ME turn off ME_RDY.\n");

 		dev_err(&dev->pdev->dev, "link layer initialization failed.\n");
 		ret = -ENODEV;
 		goto out;
 	}

 	if (dev->version.major_version != HBM_MAJOR_VERSION ||
 	    dev->version.minor_version != HBM_MINOR_VERSION) {
 		dev_dbg(&dev->pdev->dev, "MEI start failed.\n");
 		ret = -ENODEV;
 		goto out;
 	}

 	dev->recvd_msg = false;
 	dev_dbg(&dev->pdev->dev, "host_hw_state = 0x%08x, me_hw_state = 0x%08x.\n",
 	    dev->host_hw_state, dev->me_hw_state);
 	dev_dbg(&dev->pdev->dev, "ME turn on ME_RDY and host turn on H_RDY.\n");
 	dev_dbg(&dev->pdev->dev, "link layer has been established.\n");
 	dev_dbg(&dev->pdev->dev, "MEI  start success.\n");
 	ret = 0;

 out:
 	mutex_unlock(&dev->device_lock);
 	return ret;
 }

 /**
  * mei_hw_reset - resets fw via mei csr register.
  *
  * @dev: the device structure
  * @interrupts_enabled: if interrupt should be enabled after reset.
  */
 static void mei_hw_reset(struct mei_device *dev, int interrupts_enabled)
 {
 	dev->host_hw_state |= (H_RST | H_IG);

 	if (interrupts_enabled)
 		mei_enable_interrupts(dev);
 	else
 		mei_disable_interrupts(dev);
 }

 /**
  * mei_reset - resets host and fw.
  *
  * @dev: the device structure
  * @interrupts_enabled: if interrupt should be enabled after reset.
  */
 void mei_reset(struct mei_device *dev, int interrupts_enabled)
 {
 	struct mei_cl *cl_pos = NULL;
 	struct mei_cl *cl_next = NULL;
 	struct mei_cl_cb *cb_pos = NULL;
 	struct mei_cl_cb *cb_next = NULL;
 	bool unexpected;

 	if (dev->dev_state == MEI_DEV_RECOVERING_FROM_RESET) {
 		dev->need_reset = true;
 		return;
 	}

 	unexpected = (dev->dev_state != MEI_DEV_INITIALIZING &&
 			dev->dev_state != MEI_DEV_DISABLED &&
 			dev->dev_state != MEI_DEV_POWER_DOWN &&
 			dev->dev_state != MEI_DEV_POWER_UP);

 	dev->host_hw_state = mei_hcsr_read(dev);

 	dev_dbg(&dev->pdev->dev, "before reset host_hw_state = 0x%08x.\n",
 	    dev->host_hw_state);

 	mei_hw_reset(dev, interrupts_enabled);

 	dev->host_hw_state &= ~H_RST;
 	dev->host_hw_state |= H_IG;

 	mei_hcsr_set(dev);

 	dev_dbg(&dev->pdev->dev, "currently saved host_hw_state = 0x%08x.\n",
 	    dev->host_hw_state);

 	dev->need_reset = false;

 	if (dev->dev_state != MEI_DEV_INITIALIZING) {
 		if (dev->dev_state != MEI_DEV_DISABLED &&
 		    dev->dev_state != MEI_DEV_POWER_DOWN)
 			dev->dev_state = MEI_DEV_RESETING;

 		list_for_each_entry_safe(cl_pos,
 				cl_next, &dev->file_list, link) {
 			cl_pos->state = MEI_FILE_DISCONNECTED;
 			cl_pos->mei_flow_ctrl_creds = 0;
 			cl_pos->read_cb = NULL;
 			cl_pos->timer_count = 0;
 		}
 		/* remove entry if already in list */
 		dev_dbg(&dev->pdev->dev, "remove iamthif and wd from the file list.\n");
 		mei_me_cl_unlink(dev, &dev->wd_cl);

 		mei_me_cl_unlink(dev, &dev->iamthif_cl);

 		mei_amthif_reset_params(dev);
 		memset(&dev->wr_ext_msg, 0, sizeof(dev->wr_ext_msg));
 	}

 	dev->me_clients_num = 0;
 	dev->rd_msg_hdr = 0;
 	dev->wd_pending = false;

 	/* update the state of the registers after reset */
 	dev->host_hw_state = mei_hcsr_read(dev);
 	dev->me_hw_state = mei_mecsr_read(dev);

 	dev_dbg(&dev->pdev->dev, "after reset host_hw_state = 0x%08x, me_hw_state = 0x%08x.\n",
 	    dev->host_hw_state, dev->me_hw_state);

 	if (unexpected)
 		dev_warn(&dev->pdev->dev, "unexpected reset: dev_state = %s\n",
 			 mei_dev_state_str(dev->dev_state));

 	/* Wake up all readings so they can be interrupted */
 	list_for_each_entry_safe(cl_pos, cl_next, &dev->file_list, link) {
 		if (waitqueue_active(&cl_pos->rx_wait)) {
 			dev_dbg(&dev->pdev->dev, "Waking up client!\n");
 			wake_up_interruptible(&cl_pos->rx_wait);
 		}
 	}
 	/* remove all waiting requests */
 	list_for_each_entry_safe(cb_pos, cb_next, &dev->write_list.list, list) {
 		list_del(&cb_pos->list);
 		mei_io_cb_free(cb_pos);
 	}
 }


 /**
  * host_start_message - mei host sends start message.
  *
  * @dev: the device structure
  *
  * returns none.
  */
 void mei_host_start_message(struct mei_device *dev)
 {
 	struct mei_msg_hdr *mei_hdr;
 	struct hbm_host_version_request *start_req;
 	const size_t len = sizeof(struct hbm_host_version_request);

 	mei_hdr = mei_hbm_hdr(&dev->wr_msg_buf[0], len);

 	/* host start message */
 	start_req = (struct hbm_host_version_request *)&dev->wr_msg_buf[1];
 	memset(start_req, 0, len);
 	start_req->hbm_cmd = HOST_START_REQ_CMD;
 	start_req->host_version.major_version = HBM_MAJOR_VERSION;
 	start_req->host_version.minor_version = HBM_MINOR_VERSION;

 	dev->recvd_msg = false;
 	if (mei_write_message(dev, mei_hdr, (unsigned char *)start_req, len)) {
 		dev_dbg(&dev->pdev->dev, "write send version message to FW fail.\n");
 		dev->dev_state = MEI_DEV_RESETING;
 		mei_reset(dev, 1);
 	}
 	dev->init_clients_state = MEI_START_MESSAGE;
 	dev->init_clients_timer = MEI_CLIENTS_INIT_TIMEOUT;
 	return ;
 }

 /**
  * host_enum_clients_message - host sends enumeration client request message.
  *
  * @dev: the device structure
  *
  * returns none.
  */
 void mei_host_enum_clients_message(struct mei_device *dev)
 {
 	struct mei_msg_hdr *mei_hdr;
 	struct hbm_host_enum_request *enum_req;
 	const size_t len = sizeof(struct hbm_host_enum_request);
 	/* enumerate clients */
 	mei_hdr = mei_hbm_hdr(&dev->wr_msg_buf[0], len);

 	enum_req = (struct hbm_host_enum_request *) &dev->wr_msg_buf[1];
 	memset(enum_req, 0, sizeof(struct hbm_host_enum_request));
 	enum_req->hbm_cmd = HOST_ENUM_REQ_CMD;

 	if (mei_write_message(dev, mei_hdr, (unsigned char *)enum_req, len)) {
 		dev->dev_state = MEI_DEV_RESETING;
 		dev_dbg(&dev->pdev->dev, "write send enumeration request message to FW fail.\n");
 		mei_reset(dev, 1);
 	}
 	dev->init_clients_state = MEI_ENUM_CLIENTS_MESSAGE;
 	dev->init_clients_timer = MEI_CLIENTS_INIT_TIMEOUT;
 	return;
 }


 /**
  * allocate_me_clients_storage - allocates storage for me clients
  *
  * @dev: the device structure
  *
  * returns none.
  */
 void mei_allocate_me_clients_storage(struct mei_device *dev)
 {
 	struct mei_me_client *clients;
 	int b;

 	/* count how many ME clients we have */
 	for_each_set_bit(b, dev->me_clients_map, MEI_CLIENTS_MAX)
 		dev->me_clients_num++;

 	if (dev->me_clients_num <= 0)
 		return ;


 	if (dev->me_clients != NULL) {
 		kfree(dev->me_clients);
 		dev->me_clients = NULL;
 	}
 	dev_dbg(&dev->pdev->dev, "memory allocation for ME clients size=%zd.\n",
 		dev->me_clients_num * sizeof(struct mei_me_client));
 	/* allocate storage for ME clients representation */
 	clients = kcalloc(dev->me_clients_num,
 			sizeof(struct mei_me_client), GFP_KERNEL);
 	if (!clients) {
 		dev_dbg(&dev->pdev->dev, "memory allocation for ME clients failed.\n");
 		dev->dev_state = MEI_DEV_RESETING;
 		mei_reset(dev, 1);
 		return ;
 	}
 	dev->me_clients = clients;
 	return ;
 }

 void mei_host_client_init(struct work_struct *work)
 {
 	struct mei_device *dev = container_of(work,
 					      struct mei_device, init_work);
 	struct mei_client_properties *client_props;
 	int i;

 	mutex_lock(&dev->device_lock);

 	bitmap_zero(dev->host_clients_map, MEI_CLIENTS_MAX);
 	dev->open_handle_count = 0;

 	/*
 	 * Reserving the first three client IDs
 	 * 0: Reserved for MEI Bus Message communications
 	 * 1: Reserved for Watchdog
 	 * 2: Reserved for AMTHI
 	 */
 	bitmap_set(dev->host_clients_map, 0, 3);

 	for (i = 0; i < dev->me_clients_num; i++) {
 		client_props = &dev->me_clients[i].props;

 		if (!uuid_le_cmp(client_props->protocol_name, mei_amthi_guid))
 			mei_amthif_host_init(dev);
 		else if (!uuid_le_cmp(client_props->protocol_name, mei_wd_guid))
 			mei_wd_host_init(dev);
 	}

 	dev->dev_state = MEI_DEV_ENABLED;

 	mutex_unlock(&dev->device_lock);
 }

 int mei_host_client_enumerate(struct mei_device *dev)
 {

 	struct mei_msg_hdr *mei_hdr;
 	struct hbm_props_request *prop_req;
 	const size_t len = sizeof(struct hbm_props_request);
 	unsigned long next_client_index;
 	u8 client_num;


 	client_num = dev->me_client_presentation_num;

 	next_client_index = find_next_bit(dev->me_clients_map, MEI_CLIENTS_MAX,
 					  dev->me_client_index);

 	/* We got all client properties */
 	if (next_client_index == MEI_CLIENTS_MAX) {
 		schedule_work(&dev->init_work);

 		return 0;
 	}

 	dev->me_clients[client_num].client_id = next_client_index;
 	dev->me_clients[client_num].mei_flow_ctrl_creds = 0;

 	mei_hdr = mei_hbm_hdr(&dev->wr_msg_buf[0], len);
 	prop_req = (struct hbm_props_request *)&dev->wr_msg_buf[1];

 	memset(prop_req, 0, sizeof(struct hbm_props_request));


 	prop_req->hbm_cmd = HOST_CLIENT_PROPERTIES_REQ_CMD;
 	prop_req->address = next_client_index;

 	if (mei_write_message(dev, mei_hdr, (unsigned char *) prop_req,
 			      mei_hdr->length)) {
 		dev->dev_state = MEI_DEV_RESETING;
 		dev_err(&dev->pdev->dev, "Properties request command failed\n");
 		mei_reset(dev, 1);

 		return -EIO;
 	}

 	dev->init_clients_timer = MEI_CLIENTS_INIT_TIMEOUT;
 	dev->me_client_index = next_client_index;

 	return 0;
 }

 /**
  * mei_init_file_private - initializes private file structure.
  *
  * @priv: private file structure to be initialized
  * @file: the file structure
  */
 void mei_cl_init(struct mei_cl *priv, struct mei_device *dev)
 {
 	memset(priv, 0, sizeof(struct mei_cl));
 	init_waitqueue_head(&priv->wait);
 	init_waitqueue_head(&priv->rx_wait);
 	init_waitqueue_head(&priv->tx_wait);
 	INIT_LIST_HEAD(&priv->link);
 	priv->reading_state = MEI_IDLE;
 	priv->writing_state = MEI_IDLE;
 	priv->dev = dev;
 }

 int mei_me_cl_by_uuid(const struct mei_device *dev, const uuid_le *cuuid)
 {
 	int i, res = -ENOENT;

 	for (i = 0; i < dev->me_clients_num; ++i)
 		if (uuid_le_cmp(*cuuid,
 				dev->me_clients[i].props.protocol_name) == 0) {
 			res = i;
 			break;
 		}

 	return res;
 }


 /**
  * mei_me_cl_link - create link between host and me clinet and add
  *   me_cl to the list
  *
  * @dev: the device structure
  * @cl: link between me and host client assocated with opened file descriptor
  * @cuuid: uuid of ME client
  * @client_id: id of the host client
  *
  * returns ME client index if ME client
  *	-EINVAL on incorrect values
  *	-ENONET if client not found
  */
 int mei_me_cl_link(struct mei_device *dev, struct mei_cl *cl,
 			const uuid_le *cuuid, u8 host_cl_id)
 {
 	int i;

 	if (!dev || !cl || !cuuid)
 		return -EINVAL;

 	/* check for valid client id */
 	i = mei_me_cl_by_uuid(dev, cuuid);
 	if (i >= 0) {
 		cl->me_client_id = dev->me_clients[i].client_id;
 		cl->state = MEI_FILE_CONNECTING;
 		cl->host_client_id = host_cl_id;

 		list_add_tail(&cl->link, &dev->file_list);
 		return (u8)i;
 	}

 	return -ENOENT;
 }
 /**
  * mei_me_cl_unlink - remove me_cl from the list
  *
  * @dev: the device structure
  * @host_client_id: host client id to be removed
  */
 void mei_me_cl_unlink(struct mei_device *dev, struct mei_cl *cl)
 {
 	struct mei_cl *pos, *next;
 	list_for_each_entry_safe(pos, next, &dev->file_list, link) {
 		if (cl->host_client_id == pos->host_client_id) {
 			dev_dbg(&dev->pdev->dev, "remove host client = %d, ME client = %d\n",
 					pos->host_client_id, pos->me_client_id);
 			list_del_init(&pos->link);
 			break;
 		}
 	}
 }

 /**
  * mei_alloc_file_private - allocates a private file structure and sets it up.
  * @file: the file structure
  *
  * returns  The allocated file or NULL on failure
  */
 struct mei_cl *mei_cl_allocate(struct mei_device *dev)
 {
 	struct mei_cl *cl;

 	cl = kmalloc(sizeof(struct mei_cl), GFP_KERNEL);
 	if (!cl)
 		return NULL;

 	mei_cl_init(cl, dev);

 	return cl;
 }


 /**
  * mei_disconnect_host_client - sends disconnect message to fw from host client.
  *
  * @dev: the device structure
  * @cl: private data of the file object
  *
  * Locking: called under "dev->device_lock" lock
  *
  * returns 0 on success, <0 on failure.
  */
 int mei_disconnect_host_client(struct mei_device *dev, struct mei_cl *cl)
 {
 	struct mei_cl_cb *cb;
 	int rets, err;

 	if (!dev || !cl)
 		return -ENODEV;

 	if (cl->state != MEI_FILE_DISCONNECTING)
 		return 0;

 	cb = mei_io_cb_init(cl, NULL);
 	if (!cb)
 		return -ENOMEM;

 	cb->fop_type = MEI_FOP_CLOSE;
 	if (dev->mei_host_buffer_is_empty) {
 		dev->mei_host_buffer_is_empty = false;
 		if (mei_disconnect(dev, cl)) {
 			rets = -ENODEV;
 			dev_dbg(&dev->pdev->dev, "failed to call mei_disconnect.\n");
 			goto free;
 		}
 		mdelay(10); /* Wait for hardware disconnection ready */
 		list_add_tail(&cb->list, &dev->ctrl_rd_list.list);
 	} else {
 		dev_dbg(&dev->pdev->dev, "add disconnect cb to control write list\n");
 		list_add_tail(&cb->list, &dev->ctrl_wr_list.list);

 	}
 	mutex_unlock(&dev->device_lock);

 	err = wait_event_timeout(dev->wait_recvd_msg,
 			MEI_FILE_DISCONNECTED == cl->state,
 			mei_secs_to_jiffies(MEI_CL_CONNECT_TIMEOUT));

 	mutex_lock(&dev->device_lock);
 	if (MEI_FILE_DISCONNECTED == cl->state) {
 		rets = 0;
 		dev_dbg(&dev->pdev->dev, "successfully disconnected from FW client.\n");
 	} else {
 		rets = -ENODEV;
 		if (MEI_FILE_DISCONNECTED != cl->state)
 			dev_dbg(&dev->pdev->dev, "wrong status client disconnect.\n");

 		if (err)
 			dev_dbg(&dev->pdev->dev,
 					"wait failed disconnect err=%08x\n",
 					err);

 		dev_dbg(&dev->pdev->dev, "failed to disconnect from FW client.\n");
 	}

 	mei_io_list_flush(&dev->ctrl_rd_list, cl);
 	mei_io_list_flush(&dev->ctrl_wr_list, cl);
 free:
 	mei_io_cb_free(cb);
 	return rets;
 }
	/*
	*
	* Intel Management Engine Interface (Intel MEI) Linux driver
	* Copyright (c) 2003-2012, Intel Corporation.
	*
	* This program is free software; you can redistribute it and/or modify it
	* under the terms and conditions of the GNU General Public License,
	* version 2, as published by the Free Software Foundation.
	*
	* This program is distributed in the hope it will be useful, but WITHOUT
	* ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
	* FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
	* more details.
	*
	*/

	#include <linux/pci.h>
	#include <linux/sched.h>
	#include <linux/wait.h>
	#include <linux/delay.h>

	#include "mei_dev.h"
	#include "hw.h"
	#include "interface.h"
	#include <linux/mei.h>

	const char *mei_dev_state_str(int state)
	{
	#define MEI_DEV_STATE(state) case MEI_DEV_##state: return #state
	switch (state) {
	MEI_DEV_STATE(INITIALIZING);
	MEI_DEV_STATE(INIT_CLIENTS);
	MEI_DEV_STATE(ENABLED);
	MEI_DEV_STATE(RESETING);
	MEI_DEV_STATE(DISABLED);
	MEI_DEV_STATE(RECOVERING_FROM_RESET);
	MEI_DEV_STATE(POWER_DOWN);
	MEI_DEV_STATE(POWER_UP);
	default:
	return "unkown";
	}
	#undef MEI_DEV_STATE
	}



	/**
	* mei_io_list_flush - removes list entry belonging to cl.
	*
	* @list: An instance of our list structure
	* @cl: private data of the file object
	*/
	void mei_io_list_flush(struct mei_cl_cb list, struct mei_cl cl)
	{
	struct mei_cl_cb *pos;
	struct mei_cl_cb *next;

	list_for_each_entry_safe(pos, next, &list->list, list) {
	if (pos->cl) {
	if (mei_cl_cmp_id(cl, pos->cl))
	list_del(&pos->list);
	}
	}
	}
	/**
	* mei_cl_flush_queues - flushes queue lists belonging to cl.
	*
	* @dev: the device structure
	* @cl: private data of the file object
	*/
	int mei_cl_flush_queues(struct mei_cl *cl)
	{
	if (!cl \|\| !cl->dev)
	return -EINVAL;

	dev_dbg(&cl->dev->pdev->dev, "remove list entry belonging to cl\n");
	mei_io_list_flush(&cl->dev->read_list, cl);
	mei_io_list_flush(&cl->dev->write_list, cl);
	mei_io_list_flush(&cl->dev->write_waiting_list, cl);
	mei_io_list_flush(&cl->dev->ctrl_wr_list, cl);
	mei_io_list_flush(&cl->dev->ctrl_rd_list, cl);
	mei_io_list_flush(&cl->dev->amthif_cmd_list, cl);
	mei_io_list_flush(&cl->dev->amthif_rd_complete_list, cl);
	return 0;
	}



	/**
	* init_mei_device - allocates and initializes the mei device structure
	*
	* @pdev: The pci device structure
	*
	* returns The mei_device_device pointer on success, NULL on failure.
	*/
	struct mei_device mei_device_init(struct pci_dev pdev)
	{
	struct mei_device *dev;

	dev = kzalloc(sizeof(struct mei_device), GFP_KERNEL);
	if (!dev)
	return NULL;

	/* setup our list array */
	INIT_LIST_HEAD(&dev->file_list);
	INIT_LIST_HEAD(&dev->wd_cl.link);
	INIT_LIST_HEAD(&dev->iamthif_cl.link);
	mutex_init(&dev->device_lock);
	init_waitqueue_head(&dev->wait_recvd_msg);
	init_waitqueue_head(&dev->wait_stop_wd);
	dev->dev_state = MEI_DEV_INITIALIZING;
	dev->iamthif_state = MEI_IAMTHIF_IDLE;

	mei_io_list_init(&dev->read_list);
	mei_io_list_init(&dev->write_list);
	mei_io_list_init(&dev->write_waiting_list);
	mei_io_list_init(&dev->ctrl_wr_list);
	mei_io_list_init(&dev->ctrl_rd_list);
	mei_io_list_init(&dev->amthif_cmd_list);
	mei_io_list_init(&dev->amthif_rd_complete_list);
	dev->pdev = pdev;
	return dev;
	}

	/**
	* mei_hw_init - initializes host and fw to start work.
	*
	* @dev: the device structure
	*
	* returns 0 on success, <0 on failure.
	*/
	int mei_hw_init(struct mei_device *dev)
	{
	int err = 0;
	int ret;

	mutex_lock(&dev->device_lock);

	dev->host_hw_state = mei_hcsr_read(dev);
	dev->me_hw_state = mei_mecsr_read(dev);
	dev_dbg(&dev->pdev->dev, "host_hw_state = 0x%08x, mestate = 0x%08x.\n",
	dev->host_hw_state, dev->me_hw_state);

	/* acknowledge interrupt and stop interupts */
	if ((dev->host_hw_state & H_IS) == H_IS)
	mei_reg_write(dev, H_CSR, dev->host_hw_state);

	/* Doesn't change in runtime */
	dev->hbuf_depth = (dev->host_hw_state & H_CBD) >> 24;

	dev->recvd_msg = false;
	dev_dbg(&dev->pdev->dev, "reset in start the mei device.\n");

	mei_reset(dev, 1);

	dev_dbg(&dev->pdev->dev, "host_hw_state = 0x%08x, me_hw_state = 0x%08x.\n",
	dev->host_hw_state, dev->me_hw_state);

	/* wait for ME to turn on ME_RDY */
	if (!dev->recvd_msg) {
	mutex_unlock(&dev->device_lock);
	err = wait_event_interruptible_timeout(dev->wait_recvd_msg,
	dev->recvd_msg,
	mei_secs_to_jiffies(MEI_INTEROP_TIMEOUT));
	mutex_lock(&dev->device_lock);
	}

	if (err <= 0 && !dev->recvd_msg) {
	dev->dev_state = MEI_DEV_DISABLED;
	dev_dbg(&dev->pdev->dev,
	"wait_event_interruptible_timeout failed"
	"on wait for ME to turn on ME_RDY.\n");
	ret = -ENODEV;
	goto out;
	}

	if (!(((dev->host_hw_state & H_RDY) == H_RDY) &&
	((dev->me_hw_state & ME_RDY_HRA) == ME_RDY_HRA))) {
	dev->dev_state = MEI_DEV_DISABLED;
	dev_dbg(&dev->pdev->dev,
	"host_hw_state = 0x%08x, me_hw_state = 0x%08x.\n",
	dev->host_hw_state, dev->me_hw_state);

	if (!(dev->host_hw_state & H_RDY))
	dev_dbg(&dev->pdev->dev, "host turn off H_RDY.\n");

	if (!(dev->me_hw_state & ME_RDY_HRA))
	dev_dbg(&dev->pdev->dev, "ME turn off ME_RDY.\n");

	dev_err(&dev->pdev->dev, "link layer initialization failed.\n");
	ret = -ENODEV;
	goto out;
	}

	if (dev->version.major_version != HBM_MAJOR_VERSION \|\|
	dev->version.minor_version != HBM_MINOR_VERSION) {
	dev_dbg(&dev->pdev->dev, "MEI start failed.\n");
	ret = -ENODEV;
	goto out;
	}

	dev->recvd_msg = false;
	dev_dbg(&dev->pdev->dev, "host_hw_state = 0x%08x, me_hw_state = 0x%08x.\n",
	dev->host_hw_state, dev->me_hw_state);
	dev_dbg(&dev->pdev->dev, "ME turn on ME_RDY and host turn on H_RDY.\n");
	dev_dbg(&dev->pdev->dev, "link layer has been established.\n");
	dev_dbg(&dev->pdev->dev, "MEI start success.\n");
	ret = 0;

	out:
	mutex_unlock(&dev->device_lock);
	return ret;
	}

	/**
	* mei_hw_reset - resets fw via mei csr register.
	*
	* @dev: the device structure
	* @interrupts_enabled: if interrupt should be enabled after reset.
	*/
	static void mei_hw_reset(struct mei_device *dev, int interrupts_enabled)
	{
	dev->host_hw_state \|= (H_RST \| H_IG);

	if (interrupts_enabled)
	mei_enable_interrupts(dev);
	else
	mei_disable_interrupts(dev);
	}

	/**
	* mei_reset - resets host and fw.
	*
	* @dev: the device structure
	* @interrupts_enabled: if interrupt should be enabled after reset.
	*/
	void mei_reset(struct mei_device *dev, int interrupts_enabled)
	{
	struct mei_cl *cl_pos = NULL;
	struct mei_cl *cl_next = NULL;
	struct mei_cl_cb *cb_pos = NULL;
	struct mei_cl_cb *cb_next = NULL;
	bool unexpected;

	if (dev->dev_state == MEI_DEV_RECOVERING_FROM_RESET) {
	dev->need_reset = true;
	return;
	}

	unexpected = (dev->dev_state != MEI_DEV_INITIALIZING &&
	dev->dev_state != MEI_DEV_DISABLED &&
	dev->dev_state != MEI_DEV_POWER_DOWN &&
	dev->dev_state != MEI_DEV_POWER_UP);

	dev->host_hw_state = mei_hcsr_read(dev);

	dev_dbg(&dev->pdev->dev, "before reset host_hw_state = 0x%08x.\n",
	dev->host_hw_state);

	mei_hw_reset(dev, interrupts_enabled);

	dev->host_hw_state &= ~H_RST;
	dev->host_hw_state \|= H_IG;

	mei_hcsr_set(dev);

	dev_dbg(&dev->pdev->dev, "currently saved host_hw_state = 0x%08x.\n",
	dev->host_hw_state);

	dev->need_reset = false;

	if (dev->dev_state != MEI_DEV_INITIALIZING) {
	if (dev->dev_state != MEI_DEV_DISABLED &&
	dev->dev_state != MEI_DEV_POWER_DOWN)
	dev->dev_state = MEI_DEV_RESETING;

	list_for_each_entry_safe(cl_pos,
	cl_next, &dev->file_list, link) {
	cl_pos->state = MEI_FILE_DISCONNECTED;
	cl_pos->mei_flow_ctrl_creds = 0;
	cl_pos->read_cb = NULL;
	cl_pos->timer_count = 0;
	}
	/* remove entry if already in list */
	dev_dbg(&dev->pdev->dev, "remove iamthif and wd from the file list.\n");
	mei_me_cl_unlink(dev, &dev->wd_cl);

	mei_me_cl_unlink(dev, &dev->iamthif_cl);

	mei_amthif_reset_params(dev);
	memset(&dev->wr_ext_msg, 0, sizeof(dev->wr_ext_msg));
	}

	dev->me_clients_num = 0;
	dev->rd_msg_hdr = 0;
	dev->wd_pending = false;

	/* update the state of the registers after reset */
	dev->host_hw_state = mei_hcsr_read(dev);
	dev->me_hw_state = mei_mecsr_read(dev);

	dev_dbg(&dev->pdev->dev, "after reset host_hw_state = 0x%08x, me_hw_state = 0x%08x.\n",
	dev->host_hw_state, dev->me_hw_state);

	if (unexpected)
	dev_warn(&dev->pdev->dev, "unexpected reset: dev_state = %s\n",
	mei_dev_state_str(dev->dev_state));

	/* Wake up all readings so they can be interrupted */
	list_for_each_entry_safe(cl_pos, cl_next, &dev->file_list, link) {
	if (waitqueue_active(&cl_pos->rx_wait)) {
	dev_dbg(&dev->pdev->dev, "Waking up client!\n");
	wake_up_interruptible(&cl_pos->rx_wait);
	}
	}
	/* remove all waiting requests */
	list_for_each_entry_safe(cb_pos, cb_next, &dev->write_list.list, list) {
	list_del(&cb_pos->list);
	mei_io_cb_free(cb_pos);
	}
	}



	/**
	* host_start_message - mei host sends start message.
	*
	* @dev: the device structure
	*
	* returns none.
	*/
	void mei_host_start_message(struct mei_device *dev)
	{
	struct mei_msg_hdr *mei_hdr;
	struct hbm_host_version_request *start_req;
	const size_t len = sizeof(struct hbm_host_version_request);

	mei_hdr = mei_hbm_hdr(&dev->wr_msg_buf[0], len);

	/* host start message */
	start_req = (struct hbm_host_version_request *)&dev->wr_msg_buf[1];
	memset(start_req, 0, len);
	start_req->hbm_cmd = HOST_START_REQ_CMD;
	start_req->host_version.major_version = HBM_MAJOR_VERSION;
	start_req->host_version.minor_version = HBM_MINOR_VERSION;

	dev->recvd_msg = false;
	if (mei_write_message(dev, mei_hdr, (unsigned char *)start_req, len)) {
	dev_dbg(&dev->pdev->dev, "write send version message to FW fail.\n");
	dev->dev_state = MEI_DEV_RESETING;
	mei_reset(dev, 1);
	}
	dev->init_clients_state = MEI_START_MESSAGE;
	dev->init_clients_timer = MEI_CLIENTS_INIT_TIMEOUT;
	return ;
	}

	/**
	* host_enum_clients_message - host sends enumeration client request message.
	*
	* @dev: the device structure
	*
	* returns none.
	*/
	void mei_host_enum_clients_message(struct mei_device *dev)
	{
	struct mei_msg_hdr *mei_hdr;
	struct hbm_host_enum_request *enum_req;
	const size_t len = sizeof(struct hbm_host_enum_request);
	/* enumerate clients */
	mei_hdr = mei_hbm_hdr(&dev->wr_msg_buf[0], len);

	enum_req = (struct hbm_host_enum_request *) &dev->wr_msg_buf[1];
	memset(enum_req, 0, sizeof(struct hbm_host_enum_request));
	enum_req->hbm_cmd = HOST_ENUM_REQ_CMD;

	if (mei_write_message(dev, mei_hdr, (unsigned char *)enum_req, len)) {
	dev->dev_state = MEI_DEV_RESETING;
	dev_dbg(&dev->pdev->dev, "write send enumeration request message to FW fail.\n");
	mei_reset(dev, 1);
	}
	dev->init_clients_state = MEI_ENUM_CLIENTS_MESSAGE;
	dev->init_clients_timer = MEI_CLIENTS_INIT_TIMEOUT;
	return;
	}


	/**
	* allocate_me_clients_storage - allocates storage for me clients
	*
	* @dev: the device structure
	*
	* returns none.
	*/
	void mei_allocate_me_clients_storage(struct mei_device *dev)
	{
	struct mei_me_client *clients;
	int b;

	/* count how many ME clients we have */
	for_each_set_bit(b, dev->me_clients_map, MEI_CLIENTS_MAX)
	dev->me_clients_num++;

	if (dev->me_clients_num <= 0)
	return ;


	if (dev->me_clients != NULL) {
	kfree(dev->me_clients);
	dev->me_clients = NULL;
	}
	dev_dbg(&dev->pdev->dev, "memory allocation for ME clients size=%zd.\n",
	dev->me_clients_num * sizeof(struct mei_me_client));
	/* allocate storage for ME clients representation */
	clients = kcalloc(dev->me_clients_num,
	sizeof(struct mei_me_client), GFP_KERNEL);
	if (!clients) {
	dev_dbg(&dev->pdev->dev, "memory allocation for ME clients failed.\n");
	dev->dev_state = MEI_DEV_RESETING;
	mei_reset(dev, 1);
	return ;
	}
	dev->me_clients = clients;
	return ;
	}

	void mei_host_client_init(struct work_struct *work)
	{
	struct mei_device *dev = container_of(work,
	struct mei_device, init_work);
	struct mei_client_properties *client_props;
	int i;

	mutex_lock(&dev->device_lock);

	bitmap_zero(dev->host_clients_map, MEI_CLIENTS_MAX);
	dev->open_handle_count = 0;

	/*
	* Reserving the first three client IDs
	* 0: Reserved for MEI Bus Message communications
	* 1: Reserved for Watchdog
	* 2: Reserved for AMTHI
	*/
	bitmap_set(dev->host_clients_map, 0, 3);

	for (i = 0; i < dev->me_clients_num; i++) {
	client_props = &dev->me_clients[i].props;

	if (!uuid_le_cmp(client_props->protocol_name, mei_amthi_guid))
	mei_amthif_host_init(dev);
	else if (!uuid_le_cmp(client_props->protocol_name, mei_wd_guid))
	mei_wd_host_init(dev);
	}

	dev->dev_state = MEI_DEV_ENABLED;

	mutex_unlock(&dev->device_lock);
	}

	int mei_host_client_enumerate(struct mei_device *dev)
	{

	struct mei_msg_hdr *mei_hdr;
	struct hbm_props_request *prop_req;
	const size_t len = sizeof(struct hbm_props_request);
	unsigned long next_client_index;
	u8 client_num;


	client_num = dev->me_client_presentation_num;

	next_client_index = find_next_bit(dev->me_clients_map, MEI_CLIENTS_MAX,
	dev->me_client_index);

	/* We got all client properties */
	if (next_client_index == MEI_CLIENTS_MAX) {
	schedule_work(&dev->init_work);

	return 0;
	}

	dev->me_clients[client_num].client_id = next_client_index;
	dev->me_clients[client_num].mei_flow_ctrl_creds = 0;

	mei_hdr = mei_hbm_hdr(&dev->wr_msg_buf[0], len);
	prop_req = (struct hbm_props_request *)&dev->wr_msg_buf[1];

	memset(prop_req, 0, sizeof(struct hbm_props_request));


	prop_req->hbm_cmd = HOST_CLIENT_PROPERTIES_REQ_CMD;
	prop_req->address = next_client_index;

	if (mei_write_message(dev, mei_hdr, (unsigned char *) prop_req,
	mei_hdr->length)) {
	dev->dev_state = MEI_DEV_RESETING;
	dev_err(&dev->pdev->dev, "Properties request command failed\n");
	mei_reset(dev, 1);

	return -EIO;
	}

	dev->init_clients_timer = MEI_CLIENTS_INIT_TIMEOUT;
	dev->me_client_index = next_client_index;

	return 0;
	}

	/**
	* mei_init_file_private - initializes private file structure.
	*
	* @priv: private file structure to be initialized
	* @file: the file structure
	*/
	void mei_cl_init(struct mei_cl priv, struct mei_device dev)
	{
	memset(priv, 0, sizeof(struct mei_cl));
	init_waitqueue_head(&priv->wait);
	init_waitqueue_head(&priv->rx_wait);
	init_waitqueue_head(&priv->tx_wait);
	INIT_LIST_HEAD(&priv->link);
	priv->reading_state = MEI_IDLE;
	priv->writing_state = MEI_IDLE;
	priv->dev = dev;
	}

	int mei_me_cl_by_uuid(const struct mei_device dev, const uuid_le cuuid)
	{
	int i, res = -ENOENT;

	for (i = 0; i < dev->me_clients_num; ++i)
	if (uuid_le_cmp(*cuuid,
	dev->me_clients[i].props.protocol_name) == 0) {
	res = i;
	break;
	}

	return res;
	}


	/**
	* mei_me_cl_link - create link between host and me clinet and add
	* me_cl to the list
	*
	* @dev: the device structure
	* @cl: link between me and host client assocated with opened file descriptor
	* @cuuid: uuid of ME client
	* @client_id: id of the host client
	*
	* returns ME client index if ME client
	* -EINVAL on incorrect values
	* -ENONET if client not found
	*/
	int mei_me_cl_link(struct mei_device dev, struct mei_cl cl,
	const uuid_le *cuuid, u8 host_cl_id)
	{
	int i;

	if (!dev \|\| !cl \|\| !cuuid)
	return -EINVAL;

	/* check for valid client id */
	i = mei_me_cl_by_uuid(dev, cuuid);
	if (i >= 0) {
	cl->me_client_id = dev->me_clients[i].client_id;
	cl->state = MEI_FILE_CONNECTING;
	cl->host_client_id = host_cl_id;

	list_add_tail(&cl->link, &dev->file_list);
	return (u8)i;
	}

	return -ENOENT;
	}
	/**
	* mei_me_cl_unlink - remove me_cl from the list
	*
	* @dev: the device structure
	* @host_client_id: host client id to be removed
	*/
	void mei_me_cl_unlink(struct mei_device dev, struct mei_cl cl)
	{
	struct mei_cl pos, next;
	list_for_each_entry_safe(pos, next, &dev->file_list, link) {
	if (cl->host_client_id == pos->host_client_id) {
	dev_dbg(&dev->pdev->dev, "remove host client = %d, ME client = %d\n",
	pos->host_client_id, pos->me_client_id);
	list_del_init(&pos->link);
	break;
	}
	}
	}

	/**
	* mei_alloc_file_private - allocates a private file structure and sets it up.
	* @file: the file structure
	*
	* returns The allocated file or NULL on failure
	*/
	struct mei_cl mei_cl_allocate(struct mei_device dev)
	{
	struct mei_cl *cl;

	cl = kmalloc(sizeof(struct mei_cl), GFP_KERNEL);
	if (!cl)
	return NULL;

	mei_cl_init(cl, dev);

	return cl;
	}



	/**
	* mei_disconnect_host_client - sends disconnect message to fw from host client.
	*
	* @dev: the device structure
	* @cl: private data of the file object
	*
	* Locking: called under "dev->device_lock" lock
	*
	* returns 0 on success, <0 on failure.
	*/
	int mei_disconnect_host_client(struct mei_device dev, struct mei_cl cl)
	{
	struct mei_cl_cb *cb;
	int rets, err;

	if (!dev \|\| !cl)
	return -ENODEV;

	if (cl->state != MEI_FILE_DISCONNECTING)
	return 0;

	cb = mei_io_cb_init(cl, NULL);
	if (!cb)
	return -ENOMEM;

	cb->fop_type = MEI_FOP_CLOSE;
	if (dev->mei_host_buffer_is_empty) {
	dev->mei_host_buffer_is_empty = false;
	if (mei_disconnect(dev, cl)) {
	rets = -ENODEV;
	dev_dbg(&dev->pdev->dev, "failed to call mei_disconnect.\n");
	goto free;
	}
	mdelay(10); /* Wait for hardware disconnection ready */
	list_add_tail(&cb->list, &dev->ctrl_rd_list.list);
	} else {
	dev_dbg(&dev->pdev->dev, "add disconnect cb to control write list\n");
	list_add_tail(&cb->list, &dev->ctrl_wr_list.list);

	}
	mutex_unlock(&dev->device_lock);

	err = wait_event_timeout(dev->wait_recvd_msg,
	MEI_FILE_DISCONNECTED == cl->state,
	mei_secs_to_jiffies(MEI_CL_CONNECT_TIMEOUT));

	mutex_lock(&dev->device_lock);
	if (MEI_FILE_DISCONNECTED == cl->state) {
	rets = 0;
	dev_dbg(&dev->pdev->dev, "successfully disconnected from FW client.\n");
	} else {
	rets = -ENODEV;
	if (MEI_FILE_DISCONNECTED != cl->state)
	dev_dbg(&dev->pdev->dev, "wrong status client disconnect.\n");

	if (err)
	dev_dbg(&dev->pdev->dev,
	"wait failed disconnect err=%08x\n",
	err);

	dev_dbg(&dev->pdev->dev, "failed to disconnect from FW client.\n");
	}

	mei_io_list_flush(&dev->ctrl_rd_list, cl);
	mei_io_list_flush(&dev->ctrl_wr_list, cl);
	free:
	mei_io_cb_free(cb);
	return rets;
	}