1 // SPDX-License-Identifier: GPL-2.0 2 /* 3 * Copyright (c) 2013-2020, Intel Corporation. All rights reserved. 4 * Intel Management Engine Interface (Intel MEI) Linux driver 5 */ 6 7 #include <linux/module.h> 8 #include <linux/kernel.h> 9 #include <linux/device.h> 10 #include <linux/errno.h> 11 #include <linux/types.h> 12 #include <linux/pci.h> 13 #include <linux/init.h> 14 #include <linux/sched.h> 15 #include <linux/interrupt.h> 16 #include <linux/workqueue.h> 17 #include <linux/pm_domain.h> 18 #include <linux/pm_runtime.h> 19 20 #include <linux/mei.h> 21 22 23 #include "mei_dev.h" 24 #include "hw-txe.h" 25 26 static const struct pci_device_id mei_txe_pci_tbl[] = { 27 {PCI_VDEVICE(INTEL, 0x0F18)}, /* Baytrail */ 28 {PCI_VDEVICE(INTEL, 0x2298)}, /* Cherrytrail */ 29 30 {0, } 31 }; 32 MODULE_DEVICE_TABLE(pci, mei_txe_pci_tbl); 33 34 #ifdef CONFIG_PM 35 static inline void mei_txe_set_pm_domain(struct mei_device *dev); 36 static inline void mei_txe_unset_pm_domain(struct mei_device *dev); 37 #else 38 static inline void mei_txe_set_pm_domain(struct mei_device *dev) {} 39 static inline void mei_txe_unset_pm_domain(struct mei_device *dev) {} 40 #endif /* CONFIG_PM */ 41 42 /** 43 * mei_txe_probe - Device Initialization Routine 44 * 45 * @pdev: PCI device structure 46 * @ent: entry in mei_txe_pci_tbl 47 * 48 * Return: 0 on success, <0 on failure. 49 */ 50 static int mei_txe_probe(struct pci_dev *pdev, const struct pci_device_id *ent) 51 { 52 struct mei_device *dev; 53 struct mei_txe_hw *hw; 54 const int mask = BIT(SEC_BAR) | BIT(BRIDGE_BAR); 55 int err; 56 57 /* enable pci dev */ 58 err = pcim_enable_device(pdev); 59 if (err) { 60 dev_err(&pdev->dev, "failed to enable pci device.\n"); 61 goto end; 62 } 63 /* set PCI host mastering */ 64 pci_set_master(pdev); 65 /* pci request regions and mapping IO device memory for mei driver */ 66 err = pcim_iomap_regions(pdev, mask, KBUILD_MODNAME); 67 if (err) { 68 dev_err(&pdev->dev, "failed to get pci regions.\n"); 69 goto end; 70 } 71 72 err = pci_set_dma_mask(pdev, DMA_BIT_MASK(36)); 73 if (err) { 74 err = pci_set_dma_mask(pdev, DMA_BIT_MASK(32)); 75 if (err) { 76 dev_err(&pdev->dev, "No suitable DMA available.\n"); 77 goto end; 78 } 79 } 80 81 /* allocates and initializes the mei dev structure */ 82 dev = mei_txe_dev_init(pdev); 83 if (!dev) { 84 err = -ENOMEM; 85 goto end; 86 } 87 hw = to_txe_hw(dev); 88 hw->mem_addr = pcim_iomap_table(pdev); 89 90 pci_enable_msi(pdev); 91 92 /* clear spurious interrupts */ 93 mei_clear_interrupts(dev); 94 95 /* request and enable interrupt */ 96 if (pci_dev_msi_enabled(pdev)) 97 err = request_threaded_irq(pdev->irq, 98 NULL, 99 mei_txe_irq_thread_handler, 100 IRQF_ONESHOT, KBUILD_MODNAME, dev); 101 else 102 err = request_threaded_irq(pdev->irq, 103 mei_txe_irq_quick_handler, 104 mei_txe_irq_thread_handler, 105 IRQF_SHARED, KBUILD_MODNAME, dev); 106 if (err) { 107 dev_err(&pdev->dev, "mei: request_threaded_irq failure. irq = %d\n", 108 pdev->irq); 109 goto end; 110 } 111 112 if (mei_start(dev)) { 113 dev_err(&pdev->dev, "init hw failure.\n"); 114 err = -ENODEV; 115 goto release_irq; 116 } 117 118 pm_runtime_set_autosuspend_delay(&pdev->dev, MEI_TXI_RPM_TIMEOUT); 119 pm_runtime_use_autosuspend(&pdev->dev); 120 121 err = mei_register(dev, &pdev->dev); 122 if (err) 123 goto stop; 124 125 pci_set_drvdata(pdev, dev); 126 127 /* 128 * MEI requires to resume from runtime suspend mode 129 * in order to perform link reset flow upon system suspend. 130 */ 131 dev_pm_set_driver_flags(&pdev->dev, DPM_FLAG_NO_DIRECT_COMPLETE); 132 133 /* 134 * TXE maps runtime suspend/resume to own power gating states, 135 * hence we need to go around native PCI runtime service which 136 * eventually brings the device into D3cold/hot state. 137 * But the TXE device cannot wake up from D3 unlike from own 138 * power gating. To get around PCI device native runtime pm, 139 * TXE uses runtime pm domain handlers which take precedence. 140 */ 141 mei_txe_set_pm_domain(dev); 142 143 pm_runtime_put_noidle(&pdev->dev); 144 145 return 0; 146 147 stop: 148 mei_stop(dev); 149 release_irq: 150 mei_cancel_work(dev); 151 mei_disable_interrupts(dev); 152 free_irq(pdev->irq, dev); 153 end: 154 dev_err(&pdev->dev, "initialization failed.\n"); 155 return err; 156 } 157 158 /** 159 * mei_txe_shutdown- Device Shutdown Routine 160 * 161 * @pdev: PCI device structure 162 * 163 * mei_txe_shutdown is called from the reboot notifier 164 * it's a simplified version of remove so we go down 165 * faster. 166 */ 167 static void mei_txe_shutdown(struct pci_dev *pdev) 168 { 169 struct mei_device *dev; 170 171 dev = pci_get_drvdata(pdev); 172 if (!dev) 173 return; 174 175 dev_dbg(&pdev->dev, "shutdown\n"); 176 mei_stop(dev); 177 178 mei_txe_unset_pm_domain(dev); 179 180 mei_disable_interrupts(dev); 181 free_irq(pdev->irq, dev); 182 } 183 184 /** 185 * mei_txe_remove - Device Removal Routine 186 * 187 * @pdev: PCI device structure 188 * 189 * mei_remove is called by the PCI subsystem to alert the driver 190 * that it should release a PCI device. 191 */ 192 static void mei_txe_remove(struct pci_dev *pdev) 193 { 194 struct mei_device *dev; 195 196 dev = pci_get_drvdata(pdev); 197 if (!dev) { 198 dev_err(&pdev->dev, "mei: dev == NULL\n"); 199 return; 200 } 201 202 pm_runtime_get_noresume(&pdev->dev); 203 204 mei_stop(dev); 205 206 mei_txe_unset_pm_domain(dev); 207 208 mei_disable_interrupts(dev); 209 free_irq(pdev->irq, dev); 210 211 mei_deregister(dev); 212 } 213 214 215 #ifdef CONFIG_PM_SLEEP 216 static int mei_txe_pci_suspend(struct device *device) 217 { 218 struct pci_dev *pdev = to_pci_dev(device); 219 struct mei_device *dev = pci_get_drvdata(pdev); 220 221 if (!dev) 222 return -ENODEV; 223 224 dev_dbg(&pdev->dev, "suspend\n"); 225 226 mei_stop(dev); 227 228 mei_disable_interrupts(dev); 229 230 free_irq(pdev->irq, dev); 231 pci_disable_msi(pdev); 232 233 return 0; 234 } 235 236 static int mei_txe_pci_resume(struct device *device) 237 { 238 struct pci_dev *pdev = to_pci_dev(device); 239 struct mei_device *dev; 240 int err; 241 242 dev = pci_get_drvdata(pdev); 243 if (!dev) 244 return -ENODEV; 245 246 pci_enable_msi(pdev); 247 248 mei_clear_interrupts(dev); 249 250 /* request and enable interrupt */ 251 if (pci_dev_msi_enabled(pdev)) 252 err = request_threaded_irq(pdev->irq, 253 NULL, 254 mei_txe_irq_thread_handler, 255 IRQF_ONESHOT, KBUILD_MODNAME, dev); 256 else 257 err = request_threaded_irq(pdev->irq, 258 mei_txe_irq_quick_handler, 259 mei_txe_irq_thread_handler, 260 IRQF_SHARED, KBUILD_MODNAME, dev); 261 if (err) { 262 dev_err(&pdev->dev, "request_threaded_irq failed: irq = %d.\n", 263 pdev->irq); 264 return err; 265 } 266 267 err = mei_restart(dev); 268 269 return err; 270 } 271 #endif /* CONFIG_PM_SLEEP */ 272 273 #ifdef CONFIG_PM 274 static int mei_txe_pm_runtime_idle(struct device *device) 275 { 276 struct mei_device *dev; 277 278 dev_dbg(device, "rpm: txe: runtime_idle\n"); 279 280 dev = dev_get_drvdata(device); 281 if (!dev) 282 return -ENODEV; 283 if (mei_write_is_idle(dev)) 284 pm_runtime_autosuspend(device); 285 286 return -EBUSY; 287 } 288 static int mei_txe_pm_runtime_suspend(struct device *device) 289 { 290 struct mei_device *dev; 291 int ret; 292 293 dev_dbg(device, "rpm: txe: runtime suspend\n"); 294 295 dev = dev_get_drvdata(device); 296 if (!dev) 297 return -ENODEV; 298 299 mutex_lock(&dev->device_lock); 300 301 if (mei_write_is_idle(dev)) 302 ret = mei_txe_aliveness_set_sync(dev, 0); 303 else 304 ret = -EAGAIN; 305 306 /* keep irq on we are staying in D0 */ 307 308 dev_dbg(device, "rpm: txe: runtime suspend ret=%d\n", ret); 309 310 mutex_unlock(&dev->device_lock); 311 312 if (ret && ret != -EAGAIN) 313 schedule_work(&dev->reset_work); 314 315 return ret; 316 } 317 318 static int mei_txe_pm_runtime_resume(struct device *device) 319 { 320 struct mei_device *dev; 321 int ret; 322 323 dev_dbg(device, "rpm: txe: runtime resume\n"); 324 325 dev = dev_get_drvdata(device); 326 if (!dev) 327 return -ENODEV; 328 329 mutex_lock(&dev->device_lock); 330 331 mei_enable_interrupts(dev); 332 333 ret = mei_txe_aliveness_set_sync(dev, 1); 334 335 mutex_unlock(&dev->device_lock); 336 337 dev_dbg(device, "rpm: txe: runtime resume ret = %d\n", ret); 338 339 if (ret) 340 schedule_work(&dev->reset_work); 341 342 return ret; 343 } 344 345 /** 346 * mei_txe_set_pm_domain - fill and set pm domain structure for device 347 * 348 * @dev: mei_device 349 */ 350 static inline void mei_txe_set_pm_domain(struct mei_device *dev) 351 { 352 struct pci_dev *pdev = to_pci_dev(dev->dev); 353 354 if (pdev->dev.bus && pdev->dev.bus->pm) { 355 dev->pg_domain.ops = *pdev->dev.bus->pm; 356 357 dev->pg_domain.ops.runtime_suspend = mei_txe_pm_runtime_suspend; 358 dev->pg_domain.ops.runtime_resume = mei_txe_pm_runtime_resume; 359 dev->pg_domain.ops.runtime_idle = mei_txe_pm_runtime_idle; 360 361 dev_pm_domain_set(&pdev->dev, &dev->pg_domain); 362 } 363 } 364 365 /** 366 * mei_txe_unset_pm_domain - clean pm domain structure for device 367 * 368 * @dev: mei_device 369 */ 370 static inline void mei_txe_unset_pm_domain(struct mei_device *dev) 371 { 372 /* stop using pm callbacks if any */ 373 dev_pm_domain_set(dev->dev, NULL); 374 } 375 376 static const struct dev_pm_ops mei_txe_pm_ops = { 377 SET_SYSTEM_SLEEP_PM_OPS(mei_txe_pci_suspend, 378 mei_txe_pci_resume) 379 SET_RUNTIME_PM_OPS( 380 mei_txe_pm_runtime_suspend, 381 mei_txe_pm_runtime_resume, 382 mei_txe_pm_runtime_idle) 383 }; 384 385 #define MEI_TXE_PM_OPS (&mei_txe_pm_ops) 386 #else 387 #define MEI_TXE_PM_OPS NULL 388 #endif /* CONFIG_PM */ 389 390 /* 391 * PCI driver structure 392 */ 393 static struct pci_driver mei_txe_driver = { 394 .name = KBUILD_MODNAME, 395 .id_table = mei_txe_pci_tbl, 396 .probe = mei_txe_probe, 397 .remove = mei_txe_remove, 398 .shutdown = mei_txe_shutdown, 399 .driver.pm = MEI_TXE_PM_OPS, 400 }; 401 402 module_pci_driver(mei_txe_driver); 403 404 MODULE_AUTHOR("Intel Corporation"); 405 MODULE_DESCRIPTION("Intel(R) Trusted Execution Environment Interface"); 406 MODULE_LICENSE("GPL v2"); 407