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         dev->pdev = pdev;
  80         return dev;
  81 }
  82
  83 /**
  84  * mei_hw_init - initializes host and fw to start work.
  85  *
  86  * @dev: the device structure
  87  *
  88  * returns 0 on success, <0 on failure.
  89  */
  90 int mei_hw_init(struct mei_device *dev)
  91 {
  92         int err = 0;
  93         int ret;
  94
  95         mutex_lock(&dev->device_lock);
  96
  97         dev->host_hw_state = mei_hcsr_read(dev);
  98         dev->me_hw_state = mei_mecsr_read(dev);
  99         dev_dbg(&dev->pdev->dev, "host_hw_state = 0x%08x, mestate = 0x%08x.\n",
 100             dev->host_hw_state, dev->me_hw_state);
 101
 102         /* acknowledge interrupt and stop interupts */
 103         mei_clear_interrupts(dev);
 104
 105         /* Doesn't change in runtime */
 106         dev->hbuf_depth = (dev->host_hw_state & H_CBD) >> 24;
 107
 108         dev->recvd_msg = false;
 109         dev_dbg(&dev->pdev->dev, "reset in start the mei device.\n");
 110
 111         mei_reset(dev, 1);
 112
 113         dev_dbg(&dev->pdev->dev, "host_hw_state = 0x%08x, me_hw_state = 0x%08x.\n",
 114             dev->host_hw_state, dev->me_hw_state);
 115
 116         /* wait for ME to turn on ME_RDY */
 117         if (!dev->recvd_msg) {
 118                 mutex_unlock(&dev->device_lock);
 119                 err = wait_event_interruptible_timeout(dev->wait_recvd_msg,
 120                         dev->recvd_msg,
 121                         mei_secs_to_jiffies(MEI_INTEROP_TIMEOUT));
 122                 mutex_lock(&dev->device_lock);
 123         }
 124
 125         if (err <= 0 && !dev->recvd_msg) {
 126                 dev->dev_state = MEI_DEV_DISABLED;
 127                 dev_dbg(&dev->pdev->dev,
 128                         "wait_event_interruptible_timeout failed"
 129                         "on wait for ME to turn on ME_RDY.\n");
 130                 ret = -ENODEV;
 131                 goto out;
 132         }
 133
 134         if (!(((dev->host_hw_state & H_RDY) == H_RDY) &&
 135               ((dev->me_hw_state & ME_RDY_HRA) == ME_RDY_HRA))) {
 136                 dev->dev_state = MEI_DEV_DISABLED;
 137                 dev_dbg(&dev->pdev->dev,
 138                         "host_hw_state = 0x%08x, me_hw_state = 0x%08x.\n",
 139                         dev->host_hw_state, dev->me_hw_state);
 140
 141                 if (!(dev->host_hw_state & H_RDY))
 142                         dev_dbg(&dev->pdev->dev, "host turn off H_RDY.\n");
 143
 144                 if (!(dev->me_hw_state & ME_RDY_HRA))
 145                         dev_dbg(&dev->pdev->dev, "ME turn off ME_RDY.\n");
 146
 147                 dev_err(&dev->pdev->dev, "link layer initialization failed.\n");
 148                 ret = -ENODEV;
 149                 goto out;
 150         }
 151
 152         if (dev->version.major_version != HBM_MAJOR_VERSION ||
 153             dev->version.minor_version != HBM_MINOR_VERSION) {
 154                 dev_dbg(&dev->pdev->dev, "MEI start failed.\n");
 155                 ret = -ENODEV;
 156                 goto out;
 157         }
 158
 159         dev->recvd_msg = false;
 160         dev_dbg(&dev->pdev->dev, "host_hw_state = 0x%08x, me_hw_state = 0x%08x.\n",
 161             dev->host_hw_state, dev->me_hw_state);
 162         dev_dbg(&dev->pdev->dev, "ME turn on ME_RDY and host turn on H_RDY.\n");
 163         dev_dbg(&dev->pdev->dev, "link layer has been established.\n");
 164         dev_dbg(&dev->pdev->dev, "MEI  start success.\n");
 165         ret = 0;
 166
 167 out:
 168         mutex_unlock(&dev->device_lock);
 169         return ret;
 170 }
 171
 172 /**
 173  * mei_hw_reset - resets fw via mei csr register.
 174  *
 175  * @dev: the device structure
 176  * @interrupts_enabled: if interrupt should be enabled after reset.
 177  */
 178 static void mei_hw_reset(struct mei_device *dev, int interrupts_enabled)
 179 {
 180         dev->host_hw_state |= (H_RST | H_IG);
 181
 182         if (interrupts_enabled)
 183                 mei_enable_interrupts(dev);
 184         else
 185                 mei_disable_interrupts(dev);
 186 }
 187
 188 /**
 189  * mei_reset - resets host and fw.
 190  *
 191  * @dev: the device structure
 192  * @interrupts_enabled: if interrupt should be enabled after reset.
 193  */
 194 void mei_reset(struct mei_device *dev, int interrupts_enabled)
 195 {
 196         struct mei_cl *cl_pos = NULL;
 197         struct mei_cl *cl_next = NULL;
 198         struct mei_cl_cb *cb_pos = NULL;
 199         struct mei_cl_cb *cb_next = NULL;
 200         bool unexpected;
 201
 202         if (dev->dev_state == MEI_DEV_RECOVERING_FROM_RESET)
 203                 return;
 204
 205         unexpected = (dev->dev_state != MEI_DEV_INITIALIZING &&
 206                         dev->dev_state != MEI_DEV_DISABLED &&
 207                         dev->dev_state != MEI_DEV_POWER_DOWN &&
 208                         dev->dev_state != MEI_DEV_POWER_UP);
 209
 210         dev->host_hw_state = mei_hcsr_read(dev);
 211
 212         dev_dbg(&dev->pdev->dev, "before reset host_hw_state = 0x%08x.\n",
 213             dev->host_hw_state);
 214
 215         mei_hw_reset(dev, interrupts_enabled);
 216
 217         dev->host_hw_state &= ~H_RST;
 218         dev->host_hw_state |= H_IG;
 219
 220         mei_hcsr_set(dev);
 221
 222         dev_dbg(&dev->pdev->dev, "currently saved host_hw_state = 0x%08x.\n",
 223             dev->host_hw_state);
 224
 225         if (dev->dev_state != MEI_DEV_INITIALIZING) {
 226                 if (dev->dev_state != MEI_DEV_DISABLED &&
 227                     dev->dev_state != MEI_DEV_POWER_DOWN)
 228                         dev->dev_state = MEI_DEV_RESETING;
 229
 230                 list_for_each_entry_safe(cl_pos,
 231                                 cl_next, &dev->file_list, link) {
 232                         cl_pos->state = MEI_FILE_DISCONNECTED;
 233                         cl_pos->mei_flow_ctrl_creds = 0;
 234                         cl_pos->read_cb = NULL;
 235                         cl_pos->timer_count = 0;
 236                 }
 237                 /* remove entry if already in list */
 238                 dev_dbg(&dev->pdev->dev, "remove iamthif and wd from the file list.\n");
 239                 mei_cl_unlink(&dev->wd_cl);
 240                 if (dev->open_handle_count > 0)
 241                         dev->open_handle_count--;
 242                 mei_cl_unlink(&dev->iamthif_cl);
 243                 if (dev->open_handle_count > 0)
 244                         dev->open_handle_count--;
 245
 246                 mei_amthif_reset_params(dev);
 247                 memset(&dev->wr_ext_msg, 0, sizeof(dev->wr_ext_msg));
 248         }
 249
 250         dev->me_clients_num = 0;
 251         dev->rd_msg_hdr = 0;
 252         dev->wd_pending = false;
 253
 254         /* update the state of the registers after reset */
 255         dev->host_hw_state = mei_hcsr_read(dev);
 256         dev->me_hw_state = mei_mecsr_read(dev);
 257
 258         dev_dbg(&dev->pdev->dev, "after reset host_hw_state = 0x%08x, me_hw_state = 0x%08x.\n",
 259             dev->host_hw_state, dev->me_hw_state);
 260
 261         if (unexpected)
 262                 dev_warn(&dev->pdev->dev, "unexpected reset: dev_state = %s\n",
 263                          mei_dev_state_str(dev->dev_state));
 264
 265         /* Wake up all readings so they can be interrupted */
 266         list_for_each_entry_safe(cl_pos, cl_next, &dev->file_list, link) {
 267                 if (waitqueue_active(&cl_pos->rx_wait)) {
 268                         dev_dbg(&dev->pdev->dev, "Waking up client!\n");
 269                         wake_up_interruptible(&cl_pos->rx_wait);
 270                 }
 271         }
 272         /* remove all waiting requests */
 273         list_for_each_entry_safe(cb_pos, cb_next, &dev->write_list.list, list) {
 274                 list_del(&cb_pos->list);
 275                 mei_io_cb_free(cb_pos);
 276         }
 277 }
 278
 279
 280
 281