xref: /linux/drivers/misc/mei/pci-txe.c (revision 905e46acd3272d04566fec49afbd7ad9e2ed9ae3)
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 	* For not wake-able HW runtime pm framework
142 	* can't be used on pci device level.
143 	* Use domain runtime pm callbacks instead.
144 	*/
145 	if (!pci_dev_run_wake(pdev))
146 		mei_txe_set_pm_domain(dev);
147 
148 	pm_runtime_put_noidle(&pdev->dev);
149 
150 	return 0;
151 
152 stop:
153 	mei_stop(dev);
154 release_irq:
155 	mei_cancel_work(dev);
156 	mei_disable_interrupts(dev);
157 	free_irq(pdev->irq, dev);
158 end:
159 	dev_err(&pdev->dev, "initialization failed.\n");
160 	return err;
161 }
162 
163 /**
164  * mei_txe_remove - Device Shutdown Routine
165  *
166  * @pdev: PCI device structure
167  *
168  *  mei_txe_shutdown is called from the reboot notifier
169  *  it's a simplified version of remove so we go down
170  *  faster.
171  */
172 static void mei_txe_shutdown(struct pci_dev *pdev)
173 {
174 	struct mei_device *dev;
175 
176 	dev = pci_get_drvdata(pdev);
177 	if (!dev)
178 		return;
179 
180 	dev_dbg(&pdev->dev, "shutdown\n");
181 	mei_stop(dev);
182 
183 	if (!pci_dev_run_wake(pdev))
184 		mei_txe_unset_pm_domain(dev);
185 
186 	mei_disable_interrupts(dev);
187 	free_irq(pdev->irq, dev);
188 }
189 
190 /**
191  * mei_txe_remove - Device Removal Routine
192  *
193  * @pdev: PCI device structure
194  *
195  * mei_remove is called by the PCI subsystem to alert the driver
196  * that it should release a PCI device.
197  */
198 static void mei_txe_remove(struct pci_dev *pdev)
199 {
200 	struct mei_device *dev;
201 
202 	dev = pci_get_drvdata(pdev);
203 	if (!dev) {
204 		dev_err(&pdev->dev, "mei: dev == NULL\n");
205 		return;
206 	}
207 
208 	pm_runtime_get_noresume(&pdev->dev);
209 
210 	mei_stop(dev);
211 
212 	if (!pci_dev_run_wake(pdev))
213 		mei_txe_unset_pm_domain(dev);
214 
215 	mei_disable_interrupts(dev);
216 	free_irq(pdev->irq, dev);
217 
218 	mei_deregister(dev);
219 }
220 
221 
222 #ifdef CONFIG_PM_SLEEP
223 static int mei_txe_pci_suspend(struct device *device)
224 {
225 	struct pci_dev *pdev = to_pci_dev(device);
226 	struct mei_device *dev = pci_get_drvdata(pdev);
227 
228 	if (!dev)
229 		return -ENODEV;
230 
231 	dev_dbg(&pdev->dev, "suspend\n");
232 
233 	mei_stop(dev);
234 
235 	mei_disable_interrupts(dev);
236 
237 	free_irq(pdev->irq, dev);
238 	pci_disable_msi(pdev);
239 
240 	return 0;
241 }
242 
243 static int mei_txe_pci_resume(struct device *device)
244 {
245 	struct pci_dev *pdev = to_pci_dev(device);
246 	struct mei_device *dev;
247 	int err;
248 
249 	dev = pci_get_drvdata(pdev);
250 	if (!dev)
251 		return -ENODEV;
252 
253 	pci_enable_msi(pdev);
254 
255 	mei_clear_interrupts(dev);
256 
257 	/* request and enable interrupt */
258 	if (pci_dev_msi_enabled(pdev))
259 		err = request_threaded_irq(pdev->irq,
260 			NULL,
261 			mei_txe_irq_thread_handler,
262 			IRQF_ONESHOT, KBUILD_MODNAME, dev);
263 	else
264 		err = request_threaded_irq(pdev->irq,
265 			mei_txe_irq_quick_handler,
266 			mei_txe_irq_thread_handler,
267 			IRQF_SHARED, KBUILD_MODNAME, dev);
268 	if (err) {
269 		dev_err(&pdev->dev, "request_threaded_irq failed: irq = %d.\n",
270 				pdev->irq);
271 		return err;
272 	}
273 
274 	err = mei_restart(dev);
275 
276 	return err;
277 }
278 #endif /* CONFIG_PM_SLEEP */
279 
280 #ifdef CONFIG_PM
281 static int mei_txe_pm_runtime_idle(struct device *device)
282 {
283 	struct pci_dev *pdev = to_pci_dev(device);
284 	struct mei_device *dev;
285 
286 	dev_dbg(&pdev->dev, "rpm: txe: runtime_idle\n");
287 
288 	dev = pci_get_drvdata(pdev);
289 	if (!dev)
290 		return -ENODEV;
291 	if (mei_write_is_idle(dev))
292 		pm_runtime_autosuspend(device);
293 
294 	return -EBUSY;
295 }
296 static int mei_txe_pm_runtime_suspend(struct device *device)
297 {
298 	struct pci_dev *pdev = to_pci_dev(device);
299 	struct mei_device *dev;
300 	int ret;
301 
302 	dev_dbg(&pdev->dev, "rpm: txe: runtime suspend\n");
303 
304 	dev = pci_get_drvdata(pdev);
305 	if (!dev)
306 		return -ENODEV;
307 
308 	mutex_lock(&dev->device_lock);
309 
310 	if (mei_write_is_idle(dev))
311 		ret = mei_txe_aliveness_set_sync(dev, 0);
312 	else
313 		ret = -EAGAIN;
314 
315 	/*
316 	 * If everything is okay we're about to enter PCI low
317 	 * power state (D3) therefor we need to disable the
318 	 * interrupts towards host.
319 	 * However if device is not wakeable we do not enter
320 	 * D-low state and we need to keep the interrupt kicking
321 	 */
322 	if (!ret && pci_dev_run_wake(pdev))
323 		mei_disable_interrupts(dev);
324 
325 	dev_dbg(&pdev->dev, "rpm: txe: runtime suspend ret=%d\n", ret);
326 
327 	mutex_unlock(&dev->device_lock);
328 
329 	if (ret && ret != -EAGAIN)
330 		schedule_work(&dev->reset_work);
331 
332 	return ret;
333 }
334 
335 static int mei_txe_pm_runtime_resume(struct device *device)
336 {
337 	struct pci_dev *pdev = to_pci_dev(device);
338 	struct mei_device *dev;
339 	int ret;
340 
341 	dev_dbg(&pdev->dev, "rpm: txe: runtime resume\n");
342 
343 	dev = pci_get_drvdata(pdev);
344 	if (!dev)
345 		return -ENODEV;
346 
347 	mutex_lock(&dev->device_lock);
348 
349 	mei_enable_interrupts(dev);
350 
351 	ret = mei_txe_aliveness_set_sync(dev, 1);
352 
353 	mutex_unlock(&dev->device_lock);
354 
355 	dev_dbg(&pdev->dev, "rpm: txe: runtime resume ret = %d\n", ret);
356 
357 	if (ret)
358 		schedule_work(&dev->reset_work);
359 
360 	return ret;
361 }
362 
363 /**
364  * mei_txe_set_pm_domain - fill and set pm domain structure for device
365  *
366  * @dev: mei_device
367  */
368 static inline void mei_txe_set_pm_domain(struct mei_device *dev)
369 {
370 	struct pci_dev *pdev  = to_pci_dev(dev->dev);
371 
372 	if (pdev->dev.bus && pdev->dev.bus->pm) {
373 		dev->pg_domain.ops = *pdev->dev.bus->pm;
374 
375 		dev->pg_domain.ops.runtime_suspend = mei_txe_pm_runtime_suspend;
376 		dev->pg_domain.ops.runtime_resume = mei_txe_pm_runtime_resume;
377 		dev->pg_domain.ops.runtime_idle = mei_txe_pm_runtime_idle;
378 
379 		dev_pm_domain_set(&pdev->dev, &dev->pg_domain);
380 	}
381 }
382 
383 /**
384  * mei_txe_unset_pm_domain - clean pm domain structure for device
385  *
386  * @dev: mei_device
387  */
388 static inline void mei_txe_unset_pm_domain(struct mei_device *dev)
389 {
390 	/* stop using pm callbacks if any */
391 	dev_pm_domain_set(dev->dev, NULL);
392 }
393 
394 static const struct dev_pm_ops mei_txe_pm_ops = {
395 	SET_SYSTEM_SLEEP_PM_OPS(mei_txe_pci_suspend,
396 				mei_txe_pci_resume)
397 	SET_RUNTIME_PM_OPS(
398 		mei_txe_pm_runtime_suspend,
399 		mei_txe_pm_runtime_resume,
400 		mei_txe_pm_runtime_idle)
401 };
402 
403 #define MEI_TXE_PM_OPS	(&mei_txe_pm_ops)
404 #else
405 #define MEI_TXE_PM_OPS	NULL
406 #endif /* CONFIG_PM */
407 
408 /*
409  *  PCI driver structure
410  */
411 static struct pci_driver mei_txe_driver = {
412 	.name = KBUILD_MODNAME,
413 	.id_table = mei_txe_pci_tbl,
414 	.probe = mei_txe_probe,
415 	.remove = mei_txe_remove,
416 	.shutdown = mei_txe_shutdown,
417 	.driver.pm = MEI_TXE_PM_OPS,
418 };
419 
420 module_pci_driver(mei_txe_driver);
421 
422 MODULE_AUTHOR("Intel Corporation");
423 MODULE_DESCRIPTION("Intel(R) Trusted Execution Environment Interface");
424 MODULE_LICENSE("GPL v2");
425