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 "interface.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         dev->iamthif_state = MEI_IAMTHIF_IDLE;
  72
  73         mei_io_list_init(&dev->read_list);
  74         mei_io_list_init(&dev->write_list);
  75         mei_io_list_init(&dev->write_waiting_list);
  76         mei_io_list_init(&dev->ctrl_wr_list);
  77         mei_io_list_init(&dev->ctrl_rd_list);
  78         mei_io_list_init(&dev->amthif_cmd_list);
  79         mei_io_list_init(&dev->amthif_rd_complete_list);
  80         dev->pdev = pdev;
  81         return dev;
  82 }
  83
  84 /**
  85  * mei_hw_init - initializes host and fw to start work.
  86  *
  87  * @dev: the device structure
  88  *
  89  * returns 0 on success, <0 on failure.
  90  */
  91 int mei_hw_init(struct mei_device *dev)
  92 {
  93         int err = 0;
  94         int ret;
  95
  96         mutex_lock(&dev->device_lock);
  97
  98         dev->host_hw_state = mei_hcsr_read(dev);
  99         dev->me_hw_state = mei_mecsr_read(dev);
 100         dev_dbg(&dev->pdev->dev, "host_hw_state = 0x%08x, mestate = 0x%08x.\n",
 101             dev->host_hw_state, dev->me_hw_state);
 102
 103         /* acknowledge interrupt and stop interupts */
 104         mei_clear_interrupts(dev);
 105
 106         /* Doesn't change in runtime */
 107         dev->hbuf_depth = (dev->host_hw_state & H_CBD) >> 24;
 108
 109         dev->recvd_msg = false;
 110         dev_dbg(&dev->pdev->dev, "reset in start the mei device.\n");
 111
 112         mei_reset(dev, 1);
 113
 114         dev_dbg(&dev->pdev->dev, "host_hw_state = 0x%08x, me_hw_state = 0x%08x.\n",
 115             dev->host_hw_state, dev->me_hw_state);
 116
 117         /* wait for ME to turn on ME_RDY */
 118         if (!dev->recvd_msg) {
 119                 mutex_unlock(&dev->device_lock);
 120                 err = wait_event_interruptible_timeout(dev->wait_recvd_msg,
 121                         dev->recvd_msg,
 122                         mei_secs_to_jiffies(MEI_INTEROP_TIMEOUT));
 123                 mutex_lock(&dev->device_lock);
 124         }
 125
 126         if (err <= 0 && !dev->recvd_msg) {
 127                 dev->dev_state = MEI_DEV_DISABLED;
 128                 dev_dbg(&dev->pdev->dev,
 129                         "wait_event_interruptible_timeout failed"
 130                         "on wait for ME to turn on ME_RDY.\n");
 131                 ret = -ENODEV;
 132                 goto out;
 133         }
 134
 135         if (!(((dev->host_hw_state & H_RDY) == H_RDY) &&
 136               ((dev->me_hw_state & ME_RDY_HRA) == ME_RDY_HRA))) {
 137                 dev->dev_state = MEI_DEV_DISABLED;
 138                 dev_dbg(&dev->pdev->dev,
 139                         "host_hw_state = 0x%08x, me_hw_state = 0x%08x.\n",
 140                         dev->host_hw_state, dev->me_hw_state);
 141
 142                 if (!(dev->host_hw_state & H_RDY))
 143                         dev_dbg(&dev->pdev->dev, "host turn off H_RDY.\n");
 144
 145                 if (!(dev->me_hw_state & ME_RDY_HRA))
 146                         dev_dbg(&dev->pdev->dev, "ME turn off ME_RDY.\n");
 147
 148                 dev_err(&dev->pdev->dev, "link layer initialization failed.\n");
 149                 ret = -ENODEV;
 150                 goto out;
 151         }
 152
 153         if (dev->version.major_version != HBM_MAJOR_VERSION ||
 154             dev->version.minor_version != HBM_MINOR_VERSION) {
 155                 dev_dbg(&dev->pdev->dev, "MEI start failed.\n");
 156                 ret = -ENODEV;
 157                 goto out;
 158         }
 159
 160         dev->recvd_msg = false;
 161         dev_dbg(&dev->pdev->dev, "host_hw_state = 0x%08x, me_hw_state = 0x%08x.\n",
 162             dev->host_hw_state, dev->me_hw_state);
 163         dev_dbg(&dev->pdev->dev, "ME turn on ME_RDY and host turn on H_RDY.\n");
 164         dev_dbg(&dev->pdev->dev, "link layer has been established.\n");
 165         dev_dbg(&dev->pdev->dev, "MEI  start success.\n");
 166         ret = 0;
 167
 168 out:
 169         mutex_unlock(&dev->device_lock);
 170         return ret;
 171 }
 172
 173 /**
 174  * mei_hw_reset - resets fw via mei csr register.
 175  *
 176  * @dev: the device structure
 177  * @interrupts_enabled: if interrupt should be enabled after reset.
 178  */
 179 static void mei_hw_reset(struct mei_device *dev, int interrupts_enabled)
 180 {
 181         dev->host_hw_state |= (H_RST | H_IG);
 182
 183         if (interrupts_enabled)
 184                 mei_enable_interrupts(dev);
 185         else
 186                 mei_disable_interrupts(dev);
 187 }
 188
 189 /**
 190  * mei_reset - resets host and fw.
 191  *
 192  * @dev: the device structure
 193  * @interrupts_enabled: if interrupt should be enabled after reset.
 194  */
 195 void mei_reset(struct mei_device *dev, int interrupts_enabled)
 196 {
 197         struct mei_cl *cl_pos = NULL;
 198         struct mei_cl *cl_next = NULL;
 199         struct mei_cl_cb *cb_pos = NULL;
 200         struct mei_cl_cb *cb_next = NULL;
 201         bool unexpected;
 202
 203         if (dev->dev_state == MEI_DEV_RECOVERING_FROM_RESET) {
 204                 dev->need_reset = true;
 205                 return;
 206         }
 207
 208         unexpected = (dev->dev_state != MEI_DEV_INITIALIZING &&
 209                         dev->dev_state != MEI_DEV_DISABLED &&
 210                         dev->dev_state != MEI_DEV_POWER_DOWN &&
 211                         dev->dev_state != MEI_DEV_POWER_UP);
 212
 213         dev->host_hw_state = mei_hcsr_read(dev);
 214
 215         dev_dbg(&dev->pdev->dev, "before reset host_hw_state = 0x%08x.\n",
 216             dev->host_hw_state);
 217
 218         mei_hw_reset(dev, interrupts_enabled);
 219
 220         dev->host_hw_state &= ~H_RST;
 221         dev->host_hw_state |= H_IG;
 222
 223         mei_hcsr_set(dev);
 224
 225         dev_dbg(&dev->pdev->dev, "currently saved host_hw_state = 0x%08x.\n",
 226             dev->host_hw_state);
 227
 228         dev->need_reset = false;
 229
 230         if (dev->dev_state != MEI_DEV_INITIALIZING) {
 231                 if (dev->dev_state != MEI_DEV_DISABLED &&
 232                     dev->dev_state != MEI_DEV_POWER_DOWN)
 233                         dev->dev_state = MEI_DEV_RESETING;
 234
 235                 list_for_each_entry_safe(cl_pos,
 236                                 cl_next, &dev->file_list, link) {
 237                         cl_pos->state = MEI_FILE_DISCONNECTED;
 238                         cl_pos->mei_flow_ctrl_creds = 0;
 239                         cl_pos->read_cb = NULL;
 240                         cl_pos->timer_count = 0;
 241                 }
 242                 /* remove entry if already in list */
 243                 dev_dbg(&dev->pdev->dev, "remove iamthif and wd from the file list.\n");
 244                 mei_me_cl_unlink(dev, &dev->wd_cl);
 245
 246                 mei_me_cl_unlink(dev, &dev->iamthif_cl);
 247
 248                 mei_amthif_reset_params(dev);
 249                 memset(&dev->wr_ext_msg, 0, sizeof(dev->wr_ext_msg));
 250         }
 251
 252         dev->me_clients_num = 0;
 253         dev->rd_msg_hdr = 0;
 254         dev->wd_pending = false;
 255
 256         /* update the state of the registers after reset */
 257         dev->host_hw_state = mei_hcsr_read(dev);
 258         dev->me_hw_state = mei_mecsr_read(dev);
 259
 260         dev_dbg(&dev->pdev->dev, "after reset host_hw_state = 0x%08x, me_hw_state = 0x%08x.\n",
 261             dev->host_hw_state, dev->me_hw_state);
 262
 263         if (unexpected)
 264                 dev_warn(&dev->pdev->dev, "unexpected reset: dev_state = %s\n",
 265                          mei_dev_state_str(dev->dev_state));
 266
 267         /* Wake up all readings so they can be interrupted */
 268         list_for_each_entry_safe(cl_pos, cl_next, &dev->file_list, link) {
 269                 if (waitqueue_active(&cl_pos->rx_wait)) {
 270                         dev_dbg(&dev->pdev->dev, "Waking up client!\n");
 271                         wake_up_interruptible(&cl_pos->rx_wait);
 272                 }
 273         }
 274         /* remove all waiting requests */
 275         list_for_each_entry_safe(cb_pos, cb_next, &dev->write_list.list, list) {
 276                 list_del(&cb_pos->list);
 277                 mei_io_cb_free(cb_pos);
 278         }
 279 }
 280
 281
 282 /**
 283  * allocate_me_clients_storage - allocates storage for me clients
 284  *
 285  * @dev: the device structure
 286  *
 287  * returns none.
 288  */
 289 void mei_allocate_me_clients_storage(struct mei_device *dev)
 290 {
 291         struct mei_me_client *clients;
 292         int b;
 293
 294         /* count how many ME clients we have */
 295         for_each_set_bit(b, dev->me_clients_map, MEI_CLIENTS_MAX)
 296                 dev->me_clients_num++;
 297
 298         if (dev->me_clients_num <= 0)
 299                 return ;
 300
 301
 302         if (dev->me_clients != NULL) {
 303                 kfree(dev->me_clients);
 304                 dev->me_clients = NULL;
 305         }
 306         dev_dbg(&dev->pdev->dev, "memory allocation for ME clients size=%zd.\n",
 307                 dev->me_clients_num * sizeof(struct mei_me_client));
 308         /* allocate storage for ME clients representation */
 309         clients = kcalloc(dev->me_clients_num,
 310                         sizeof(struct mei_me_client), GFP_KERNEL);
 311         if (!clients) {
 312                 dev_dbg(&dev->pdev->dev, "memory allocation for ME clients failed.\n");
 313                 dev->dev_state = MEI_DEV_RESETING;
 314                 mei_reset(dev, 1);
 315                 return ;
 316         }
 317         dev->me_clients = clients;
 318         return ;
 319 }
 320
 321
 322