drivers/misc/mei/init.c

   1 /*
   2  *
   3  * Intel Management Engine Interface (Intel MEI) Linux driver
   4  * Copyright (c) 2003-2012, Intel Corporation.
   5  *
   6  * This program is free software; you can redistribute it and/or modify it
   7  * under the terms and conditions of the GNU General Public License,
   8  * version 2, as published by the Free Software Foundation.
   9  *
  10  * This program is distributed in the hope it will be useful, but WITHOUT
  11  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  12  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
  13  * more details.
  14  *
  15  */
  16
  17 #include <linux/pci.h>
  18 #include <linux/sched.h>
  19 #include <linux/wait.h>
  20 #include <linux/delay.h>
  21
  22 #include <linux/mei.h>
  23
  24 #include "mei_dev.h"
  25 #include "client.h"
  26
  27 const char *mei_dev_state_str(int state)
  28 {
  29 #define MEI_DEV_STATE(state) case MEI_DEV_##state: return #state
  30         switch (state) {
  31         MEI_DEV_STATE(INITIALIZING);
  32         MEI_DEV_STATE(INIT_CLIENTS);
  33         MEI_DEV_STATE(ENABLED);
  34         MEI_DEV_STATE(RESETING);
  35         MEI_DEV_STATE(DISABLED);
  36         MEI_DEV_STATE(RECOVERING_FROM_RESET);
  37         MEI_DEV_STATE(POWER_DOWN);
  38         MEI_DEV_STATE(POWER_UP);
  39         default:
  40                 return "unkown";
  41         }
  42 #undef MEI_DEV_STATE
  43 }
  44
  45
  46
  47
  48 /**
  49  * init_mei_device - allocates and initializes the mei device structure
  50  *
  51  * @pdev: The pci device structure
  52  *
  53  * returns The mei_device_device pointer on success, NULL on failure.
  54  */
  55 struct mei_device *mei_device_init(struct pci_dev *pdev)
  56 {
  57         struct mei_device *dev;
  58
  59         dev = kzalloc(sizeof(struct mei_device), GFP_KERNEL);
  60         if (!dev)
  61                 return NULL;
  62
  63         /* setup our list array */
  64         INIT_LIST_HEAD(&dev->file_list);
  65         INIT_LIST_HEAD(&dev->wd_cl.link);
  66         INIT_LIST_HEAD(&dev->iamthif_cl.link);
  67         mutex_init(&dev->device_lock);
  68         init_waitqueue_head(&dev->wait_recvd_msg);
  69         init_waitqueue_head(&dev->wait_stop_wd);
  70         dev->dev_state = MEI_DEV_INITIALIZING;
  71
  72         mei_io_list_init(&dev->read_list);
  73         mei_io_list_init(&dev->write_list);
  74         mei_io_list_init(&dev->write_waiting_list);
  75         mei_io_list_init(&dev->ctrl_wr_list);
  76         mei_io_list_init(&dev->ctrl_rd_list);
  77         mei_io_list_init(&dev->amthif_cmd_list);
  78         mei_io_list_init(&dev->amthif_rd_complete_list);
  79
  80         INIT_DELAYED_WORK(&dev->timer_work, mei_timer);
  81         INIT_WORK(&dev->init_work, mei_host_client_init);
  82
  83         dev->pdev = pdev;
  84         return dev;
  85 }
  86
  87 /**
  88  * mei_hw_init - initializes host and fw to start work.
  89  *
  90  * @dev: the device structure
  91  *
  92  * returns 0 on success, <0 on failure.
  93  */
  94 int mei_hw_init(struct mei_device *dev)
  95 {
  96         int ret = 0;
  97
  98         mutex_lock(&dev->device_lock);
  99
 100         /* acknowledge interrupt and stop interupts */
 101         mei_clear_interrupts(dev);
 102
 103         mei_hw_config(dev);
 104
 105         dev->recvd_msg = false;
 106         dev_dbg(&dev->pdev->dev, "reset in start the mei device.\n");
 107
 108         mei_reset(dev, 1);
 109
 110         /* wait for ME to turn on ME_RDY */
 111         if (!dev->recvd_msg) {
 112                 mutex_unlock(&dev->device_lock);
 113                 ret = wait_event_interruptible_timeout(dev->wait_recvd_msg,
 114                         dev->recvd_msg,
 115                         mei_secs_to_jiffies(MEI_INTEROP_TIMEOUT));
 116                 mutex_lock(&dev->device_lock);
 117         }
 118
 119         if (ret <= 0 && !dev->recvd_msg) {
 120                 dev->dev_state = MEI_DEV_DISABLED;
 121                 dev_dbg(&dev->pdev->dev,
 122                         "wait_event_interruptible_timeout failed"
 123                         "on wait for ME to turn on ME_RDY.\n");
 124                 goto err;
 125         }
 126
 127
 128         if (!mei_host_is_ready(dev)) {
 129                 dev_err(&dev->pdev->dev, "host is not ready.\n");
 130                 goto err;
 131         }
 132
 133         if (!mei_me_is_ready(dev)) {
 134                 dev_err(&dev->pdev->dev, "ME is not ready.\n");
 135                 goto err;
 136         }
 137
 138         if (dev->version.major_version != HBM_MAJOR_VERSION ||
 139             dev->version.minor_version != HBM_MINOR_VERSION) {
 140                 dev_dbg(&dev->pdev->dev, "MEI start failed.\n");
 141                 goto err;
 142         }
 143
 144         dev->recvd_msg = false;
 145         dev_dbg(&dev->pdev->dev, "link layer has been established.\n");
 146
 147         mutex_unlock(&dev->device_lock);
 148         return 0;
 149 err:
 150         dev_err(&dev->pdev->dev, "link layer initialization failed.\n");
 151         dev->dev_state = MEI_DEV_DISABLED;
 152         mutex_unlock(&dev->device_lock);
 153         return -ENODEV;
 154 }
 155
 156 /**
 157  * mei_reset - resets host and fw.
 158  *
 159  * @dev: the device structure
 160  * @interrupts_enabled: if interrupt should be enabled after reset.
 161  */
 162 void mei_reset(struct mei_device *dev, int interrupts_enabled)
 163 {
 164         struct mei_cl *cl_pos = NULL;
 165         struct mei_cl *cl_next = NULL;
 166         struct mei_cl_cb *cb_pos = NULL;
 167         struct mei_cl_cb *cb_next = NULL;
 168         bool unexpected;
 169
 170         if (dev->dev_state == MEI_DEV_RECOVERING_FROM_RESET)
 171                 return;
 172
 173         unexpected = (dev->dev_state != MEI_DEV_INITIALIZING &&
 174                         dev->dev_state != MEI_DEV_DISABLED &&
 175                         dev->dev_state != MEI_DEV_POWER_DOWN &&
 176                         dev->dev_state != MEI_DEV_POWER_UP);
 177
 178         mei_hw_reset(dev, interrupts_enabled);
 179
 180
 181         if (dev->dev_state != MEI_DEV_INITIALIZING) {
 182                 if (dev->dev_state != MEI_DEV_DISABLED &&
 183                     dev->dev_state != MEI_DEV_POWER_DOWN)
 184                         dev->dev_state = MEI_DEV_RESETING;
 185
 186                 list_for_each_entry_safe(cl_pos,
 187                                 cl_next, &dev->file_list, link) {
 188                         cl_pos->state = MEI_FILE_DISCONNECTED;
 189                         cl_pos->mei_flow_ctrl_creds = 0;
 190                         cl_pos->read_cb = NULL;
 191                         cl_pos->timer_count = 0;
 192                 }
 193                 /* remove entry if already in list */
 194                 dev_dbg(&dev->pdev->dev, "remove iamthif and wd from the file list.\n");
 195                 mei_cl_unlink(&dev->wd_cl);
 196                 if (dev->open_handle_count > 0)
 197                         dev->open_handle_count--;
 198                 mei_cl_unlink(&dev->iamthif_cl);
 199                 if (dev->open_handle_count > 0)
 200                         dev->open_handle_count--;
 201
 202                 mei_amthif_reset_params(dev);
 203                 memset(&dev->wr_ext_msg, 0, sizeof(dev->wr_ext_msg));
 204         }
 205
 206         dev->me_clients_num = 0;
 207         dev->rd_msg_hdr = 0;
 208         dev->wd_pending = false;
 209
 210         if (unexpected)
 211                 dev_warn(&dev->pdev->dev, "unexpected reset: dev_state = %s\n",
 212                          mei_dev_state_str(dev->dev_state));
 213
 214         /* Wake up all readings so they can be interrupted */
 215         list_for_each_entry_safe(cl_pos, cl_next, &dev->file_list, link) {
 216                 if (waitqueue_active(&cl_pos->rx_wait)) {
 217                         dev_dbg(&dev->pdev->dev, "Waking up client!\n");
 218                         wake_up_interruptible(&cl_pos->rx_wait);
 219                 }
 220         }
 221         /* remove all waiting requests */
 222         list_for_each_entry_safe(cb_pos, cb_next, &dev->write_list.list, list) {
 223                 list_del(&cb_pos->list);
 224                 mei_io_cb_free(cb_pos);
 225         }
 226 }
 227
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