drivers/misc/mei/pci-txe.c

   1 /*
   2  *
   3  * Intel Management Engine Interface (Intel MEI) Linux driver
   4  * Copyright (c) 2013-2014, 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/module.h>
  18 #include <linux/kernel.h>
  19 #include <linux/device.h>
  20 #include <linux/fs.h>
  21 #include <linux/errno.h>
  22 #include <linux/types.h>
  23 #include <linux/pci.h>
  24 #include <linux/init.h>
  25 #include <linux/sched.h>
  26 #include <linux/uuid.h>
  27 #include <linux/jiffies.h>
  28 #include <linux/interrupt.h>
  29 #include <linux/workqueue.h>
  30 #include <linux/pm_domain.h>
  31 #include <linux/pm_runtime.h>
  32
  33 #include <linux/mei.h>
  34
  35
  36 #include "mei_dev.h"
  37 #include "hw-txe.h"
  38
  39 static const struct pci_device_id mei_txe_pci_tbl[] = {
  40         {PCI_VDEVICE(INTEL, 0x0F18)}, /* Baytrail */
  41         {PCI_VDEVICE(INTEL, 0x2298)}, /* Cherrytrail */
  42
  43         {0, }
  44 };
  45 MODULE_DEVICE_TABLE(pci, mei_txe_pci_tbl);
  46
  47 #ifdef CONFIG_PM
  48 static inline void mei_txe_set_pm_domain(struct mei_device *dev);
  49 static inline void mei_txe_unset_pm_domain(struct mei_device *dev);
  50 #else
  51 static inline void mei_txe_set_pm_domain(struct mei_device *dev) {}
  52 static inline void mei_txe_unset_pm_domain(struct mei_device *dev) {}
  53 #endif /* CONFIG_PM */
  54
  55 /**
  56  * mei_txe_probe - Device Initialization Routine
  57  *
  58  * @pdev: PCI device structure
  59  * @ent: entry in mei_txe_pci_tbl
  60  *
  61  * Return: 0 on success, <0 on failure.
  62  */
  63 static int mei_txe_probe(struct pci_dev *pdev, const struct pci_device_id *ent)
  64 {
  65         struct mei_device *dev;
  66         struct mei_txe_hw *hw;
  67         const int mask = BIT(SEC_BAR) | BIT(BRIDGE_BAR);
  68         int err;
  69
  70         /* enable pci dev */
  71         err = pcim_enable_device(pdev);
  72         if (err) {
  73                 dev_err(&pdev->dev, "failed to enable pci device.\n");
  74                 goto end;
  75         }
  76         /* set PCI host mastering  */
  77         pci_set_master(pdev);
  78         /* pci request regions and mapping IO device memory for mei driver */
  79         err = pcim_iomap_regions(pdev, mask, KBUILD_MODNAME);
  80         if (err) {
  81                 dev_err(&pdev->dev, "failed to get pci regions.\n");
  82                 goto end;
  83         }
  84
  85         err = pci_set_dma_mask(pdev, DMA_BIT_MASK(36));
  86         if (err) {
  87                 err = pci_set_dma_mask(pdev, DMA_BIT_MASK(32));
  88                 if (err) {
  89                         dev_err(&pdev->dev, "No suitable DMA available.\n");
  90                         goto end;
  91                 }
  92         }
  93
  94         /* allocates and initializes the mei dev structure */
  95         dev = mei_txe_dev_init(pdev);
  96         if (!dev) {
  97                 err = -ENOMEM;
  98                 goto end;
  99         }
 100         hw = to_txe_hw(dev);
 101         hw->mem_addr = pcim_iomap_table(pdev);
 102
 103         pci_enable_msi(pdev);
 104
 105         /* clear spurious interrupts */
 106         mei_clear_interrupts(dev);
 107
 108         /* request and enable interrupt  */
 109         if (pci_dev_msi_enabled(pdev))
 110                 err = request_threaded_irq(pdev->irq,
 111                         NULL,
 112                         mei_txe_irq_thread_handler,
 113                         IRQF_ONESHOT, KBUILD_MODNAME, dev);
 114         else
 115                 err = request_threaded_irq(pdev->irq,
 116                         mei_txe_irq_quick_handler,
 117                         mei_txe_irq_thread_handler,
 118                         IRQF_SHARED, KBUILD_MODNAME, dev);
 119         if (err) {
 120                 dev_err(&pdev->dev, "mei: request_threaded_irq failure. irq = %d\n",
 121                         pdev->irq);
 122                 goto end;
 123         }
 124
 125         if (mei_start(dev)) {
 126                 dev_err(&pdev->dev, "init hw failure.\n");
 127                 err = -ENODEV;
 128                 goto release_irq;
 129         }
 130
 131         pm_runtime_set_autosuspend_delay(&pdev->dev, MEI_TXI_RPM_TIMEOUT);
 132         pm_runtime_use_autosuspend(&pdev->dev);
 133
 134         err = mei_register(dev, &pdev->dev);
 135         if (err)
 136                 goto stop;
 137
 138         pci_set_drvdata(pdev, dev);
 139
 140         /*
 141          * MEI requires to resume from runtime suspend mode
 142          * in order to perform link reset flow upon system suspend.
 143          */
 144         dev_pm_set_driver_flags(&pdev->dev, DPM_FLAG_NEVER_SKIP);
 145
 146         /*
 147          * TXE maps runtime suspend/resume to own power gating states,
 148          * hence we need to go around native PCI runtime service which
 149          * eventually brings the device into D3cold/hot state.
 150          * But the TXE device cannot wake up from D3 unlike from own
 151          * power gating. To get around PCI device native runtime pm,
 152          * TXE uses runtime pm domain handlers which take precedence.
 153          */
 154         mei_txe_set_pm_domain(dev);
 155
 156         pm_runtime_put_noidle(&pdev->dev);
 157
 158         return 0;
 159
 160 stop:
 161         mei_stop(dev);
 162 release_irq:
 163         mei_cancel_work(dev);
 164         mei_disable_interrupts(dev);
 165         free_irq(pdev->irq, dev);
 166 end:
 167         dev_err(&pdev->dev, "initialization failed.\n");
 168         return err;
 169 }
 170
 171 /**
 172  * mei_txe_remove - Device Shutdown Routine
 173  *
 174  * @pdev: PCI device structure
 175  *
 176  *  mei_txe_shutdown is called from the reboot notifier
 177  *  it's a simplified version of remove so we go down
 178  *  faster.
 179  */
 180 static void mei_txe_shutdown(struct pci_dev *pdev)
 181 {
 182         struct mei_device *dev;
 183
 184         dev = pci_get_drvdata(pdev);
 185         if (!dev)
 186                 return;
 187
 188         dev_dbg(&pdev->dev, "shutdown\n");
 189         mei_stop(dev);
 190
 191         mei_txe_unset_pm_domain(dev);
 192
 193         mei_disable_interrupts(dev);
 194         free_irq(pdev->irq, dev);
 195 }
 196
 197 /**
 198  * mei_txe_remove - Device Removal Routine
 199  *
 200  * @pdev: PCI device structure
 201  *
 202  * mei_remove is called by the PCI subsystem to alert the driver
 203  * that it should release a PCI device.
 204  */
 205 static void mei_txe_remove(struct pci_dev *pdev)
 206 {
 207         struct mei_device *dev;
 208
 209         dev = pci_get_drvdata(pdev);
 210         if (!dev) {
 211                 dev_err(&pdev->dev, "mei: dev == NULL\n");
 212                 return;
 213         }
 214
 215         pm_runtime_get_noresume(&pdev->dev);
 216
 217         mei_stop(dev);
 218
 219         mei_txe_unset_pm_domain(dev);
 220
 221         mei_disable_interrupts(dev);
 222         free_irq(pdev->irq, dev);
 223
 224         mei_deregister(dev);
 225 }
 226
 227
 228 #ifdef CONFIG_PM_SLEEP
 229 static int mei_txe_pci_suspend(struct device *device)
 230 {
 231         struct pci_dev *pdev = to_pci_dev(device);
 232         struct mei_device *dev = pci_get_drvdata(pdev);
 233
 234         if (!dev)
 235                 return -ENODEV;
 236
 237         dev_dbg(&pdev->dev, "suspend\n");
 238
 239         mei_stop(dev);
 240
 241         mei_disable_interrupts(dev);
 242
 243         free_irq(pdev->irq, dev);
 244         pci_disable_msi(pdev);
 245
 246         return 0;
 247 }
 248
 249 static int mei_txe_pci_resume(struct device *device)
 250 {
 251         struct pci_dev *pdev = to_pci_dev(device);
 252         struct mei_device *dev;
 253         int err;
 254
 255         dev = pci_get_drvdata(pdev);
 256         if (!dev)
 257                 return -ENODEV;
 258
 259         pci_enable_msi(pdev);
 260
 261         mei_clear_interrupts(dev);
 262
 263         /* request and enable interrupt */
 264         if (pci_dev_msi_enabled(pdev))
 265                 err = request_threaded_irq(pdev->irq,
 266                         NULL,
 267                         mei_txe_irq_thread_handler,
 268                         IRQF_ONESHOT, KBUILD_MODNAME, dev);
 269         else
 270                 err = request_threaded_irq(pdev->irq,
 271                         mei_txe_irq_quick_handler,
 272                         mei_txe_irq_thread_handler,
 273                         IRQF_SHARED, KBUILD_MODNAME, dev);
 274         if (err) {
 275                 dev_err(&pdev->dev, "request_threaded_irq failed: irq = %d.\n",
 276                                 pdev->irq);
 277                 return err;
 278         }
 279
 280         err = mei_restart(dev);
 281
 282         return err;
 283 }
 284 #endif /* CONFIG_PM_SLEEP */
 285
 286 #ifdef CONFIG_PM
 287 static int mei_txe_pm_runtime_idle(struct device *device)
 288 {
 289         struct pci_dev *pdev = to_pci_dev(device);
 290         struct mei_device *dev;
 291
 292         dev_dbg(&pdev->dev, "rpm: txe: runtime_idle\n");
 293
 294         dev = pci_get_drvdata(pdev);
 295         if (!dev)
 296                 return -ENODEV;
 297         if (mei_write_is_idle(dev))
 298                 pm_runtime_autosuspend(device);
 299
 300         return -EBUSY;
 301 }
 302 static int mei_txe_pm_runtime_suspend(struct device *device)
 303 {
 304         struct pci_dev *pdev = to_pci_dev(device);
 305         struct mei_device *dev;
 306         int ret;
 307
 308         dev_dbg(&pdev->dev, "rpm: txe: runtime suspend\n");
 309
 310         dev = pci_get_drvdata(pdev);
 311         if (!dev)
 312                 return -ENODEV;
 313
 314         mutex_lock(&dev->device_lock);
 315
 316         if (mei_write_is_idle(dev))
 317                 ret = mei_txe_aliveness_set_sync(dev, 0);
 318         else
 319                 ret = -EAGAIN;
 320
 321         /* keep irq on we are staying in D0 */
 322
 323         dev_dbg(&pdev->dev, "rpm: txe: runtime suspend ret=%d\n", ret);
 324
 325         mutex_unlock(&dev->device_lock);
 326
 327         if (ret && ret != -EAGAIN)
 328                 schedule_work(&dev->reset_work);
 329
 330         return ret;
 331 }
 332
 333 static int mei_txe_pm_runtime_resume(struct device *device)
 334 {
 335         struct pci_dev *pdev = to_pci_dev(device);
 336         struct mei_device *dev;
 337         int ret;
 338
 339         dev_dbg(&pdev->dev, "rpm: txe: runtime resume\n");
 340
 341         dev = pci_get_drvdata(pdev);
 342         if (!dev)
 343                 return -ENODEV;
 344
 345         mutex_lock(&dev->device_lock);
 346
 347         mei_enable_interrupts(dev);
 348
 349         ret = mei_txe_aliveness_set_sync(dev, 1);
 350
 351         mutex_unlock(&dev->device_lock);
 352
 353         dev_dbg(&pdev->dev, "rpm: txe: runtime resume ret = %d\n", ret);
 354
 355         if (ret)
 356                 schedule_work(&dev->reset_work);
 357
 358         return ret;
 359 }
 360
 361 /**
 362  * mei_txe_set_pm_domain - fill and set pm domain structure for device
 363  *
 364  * @dev: mei_device
 365  */
 366 static inline void mei_txe_set_pm_domain(struct mei_device *dev)
 367 {
 368         struct pci_dev *pdev  = to_pci_dev(dev->dev);
 369
 370         if (pdev->dev.bus && pdev->dev.bus->pm) {
 371                 dev->pg_domain.ops = *pdev->dev.bus->pm;
 372
 373                 dev->pg_domain.ops.runtime_suspend = mei_txe_pm_runtime_suspend;
 374                 dev->pg_domain.ops.runtime_resume = mei_txe_pm_runtime_resume;
 375                 dev->pg_domain.ops.runtime_idle = mei_txe_pm_runtime_idle;
 376
 377                 dev_pm_domain_set(&pdev->dev, &dev->pg_domain);
 378         }
 379 }
 380
 381 /**
 382  * mei_txe_unset_pm_domain - clean pm domain structure for device
 383  *
 384  * @dev: mei_device
 385  */
 386 static inline void mei_txe_unset_pm_domain(struct mei_device *dev)
 387 {
 388         /* stop using pm callbacks if any */
 389         dev_pm_domain_set(dev->dev, NULL);
 390 }
 391
 392 static const struct dev_pm_ops mei_txe_pm_ops = {
 393         SET_SYSTEM_SLEEP_PM_OPS(mei_txe_pci_suspend,
 394                                 mei_txe_pci_resume)
 395         SET_RUNTIME_PM_OPS(
 396                 mei_txe_pm_runtime_suspend,
 397                 mei_txe_pm_runtime_resume,
 398                 mei_txe_pm_runtime_idle)
 399 };
 400
 401 #define MEI_TXE_PM_OPS  (&mei_txe_pm_ops)
 402 #else
 403 #define MEI_TXE_PM_OPS  NULL
 404 #endif /* CONFIG_PM */
 405
 406 /*
 407  *  PCI driver structure
 408  */
 409 static struct pci_driver mei_txe_driver = {
 410         .name = KBUILD_MODNAME,
 411         .id_table = mei_txe_pci_tbl,
 412         .probe = mei_txe_probe,
 413         .remove = mei_txe_remove,
 414         .shutdown = mei_txe_shutdown,
 415         .driver.pm = MEI_TXE_PM_OPS,
 416 };
 417
 418 module_pci_driver(mei_txe_driver);
 419
 420 MODULE_AUTHOR("Intel Corporation");
 421 MODULE_DESCRIPTION("Intel(R) Trusted Execution Environment Interface");
 422 MODULE_LICENSE("GPL v2");