xref: /openbmc/linux/drivers/misc/mei/pci-txe.c (revision cfbb9be8)
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");
423