xref: /openbmc/linux/drivers/misc/mei/pci-txe.c (revision 1c2dd16a)
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 Removal Routine
165  *
166  * @pdev: PCI device structure
167  *
168  * mei_remove is called by the PCI subsystem to alert the driver
169  * that it should release a PCI device.
170  */
171 static void mei_txe_remove(struct pci_dev *pdev)
172 {
173 	struct mei_device *dev;
174 
175 	dev = pci_get_drvdata(pdev);
176 	if (!dev) {
177 		dev_err(&pdev->dev, "mei: dev == NULL\n");
178 		return;
179 	}
180 
181 	pm_runtime_get_noresume(&pdev->dev);
182 
183 	mei_stop(dev);
184 
185 	if (!pci_dev_run_wake(pdev))
186 		mei_txe_unset_pm_domain(dev);
187 
188 	mei_disable_interrupts(dev);
189 	free_irq(pdev->irq, dev);
190 
191 	mei_deregister(dev);
192 }
193 
194 
195 #ifdef CONFIG_PM_SLEEP
196 static int mei_txe_pci_suspend(struct device *device)
197 {
198 	struct pci_dev *pdev = to_pci_dev(device);
199 	struct mei_device *dev = pci_get_drvdata(pdev);
200 
201 	if (!dev)
202 		return -ENODEV;
203 
204 	dev_dbg(&pdev->dev, "suspend\n");
205 
206 	mei_stop(dev);
207 
208 	mei_disable_interrupts(dev);
209 
210 	free_irq(pdev->irq, dev);
211 	pci_disable_msi(pdev);
212 
213 	return 0;
214 }
215 
216 static int mei_txe_pci_resume(struct device *device)
217 {
218 	struct pci_dev *pdev = to_pci_dev(device);
219 	struct mei_device *dev;
220 	int err;
221 
222 	dev = pci_get_drvdata(pdev);
223 	if (!dev)
224 		return -ENODEV;
225 
226 	pci_enable_msi(pdev);
227 
228 	mei_clear_interrupts(dev);
229 
230 	/* request and enable interrupt */
231 	if (pci_dev_msi_enabled(pdev))
232 		err = request_threaded_irq(pdev->irq,
233 			NULL,
234 			mei_txe_irq_thread_handler,
235 			IRQF_ONESHOT, KBUILD_MODNAME, dev);
236 	else
237 		err = request_threaded_irq(pdev->irq,
238 			mei_txe_irq_quick_handler,
239 			mei_txe_irq_thread_handler,
240 			IRQF_SHARED, KBUILD_MODNAME, dev);
241 	if (err) {
242 		dev_err(&pdev->dev, "request_threaded_irq failed: irq = %d.\n",
243 				pdev->irq);
244 		return err;
245 	}
246 
247 	err = mei_restart(dev);
248 
249 	return err;
250 }
251 #endif /* CONFIG_PM_SLEEP */
252 
253 #ifdef CONFIG_PM
254 static int mei_txe_pm_runtime_idle(struct device *device)
255 {
256 	struct pci_dev *pdev = to_pci_dev(device);
257 	struct mei_device *dev;
258 
259 	dev_dbg(&pdev->dev, "rpm: txe: runtime_idle\n");
260 
261 	dev = pci_get_drvdata(pdev);
262 	if (!dev)
263 		return -ENODEV;
264 	if (mei_write_is_idle(dev))
265 		pm_runtime_autosuspend(device);
266 
267 	return -EBUSY;
268 }
269 static int mei_txe_pm_runtime_suspend(struct device *device)
270 {
271 	struct pci_dev *pdev = to_pci_dev(device);
272 	struct mei_device *dev;
273 	int ret;
274 
275 	dev_dbg(&pdev->dev, "rpm: txe: runtime suspend\n");
276 
277 	dev = pci_get_drvdata(pdev);
278 	if (!dev)
279 		return -ENODEV;
280 
281 	mutex_lock(&dev->device_lock);
282 
283 	if (mei_write_is_idle(dev))
284 		ret = mei_txe_aliveness_set_sync(dev, 0);
285 	else
286 		ret = -EAGAIN;
287 
288 	/*
289 	 * If everything is okay we're about to enter PCI low
290 	 * power state (D3) therefor we need to disable the
291 	 * interrupts towards host.
292 	 * However if device is not wakeable we do not enter
293 	 * D-low state and we need to keep the interrupt kicking
294 	 */
295 	if (!ret && pci_dev_run_wake(pdev))
296 		mei_disable_interrupts(dev);
297 
298 	dev_dbg(&pdev->dev, "rpm: txe: runtime suspend ret=%d\n", ret);
299 
300 	mutex_unlock(&dev->device_lock);
301 
302 	if (ret && ret != -EAGAIN)
303 		schedule_work(&dev->reset_work);
304 
305 	return ret;
306 }
307 
308 static int mei_txe_pm_runtime_resume(struct device *device)
309 {
310 	struct pci_dev *pdev = to_pci_dev(device);
311 	struct mei_device *dev;
312 	int ret;
313 
314 	dev_dbg(&pdev->dev, "rpm: txe: runtime resume\n");
315 
316 	dev = pci_get_drvdata(pdev);
317 	if (!dev)
318 		return -ENODEV;
319 
320 	mutex_lock(&dev->device_lock);
321 
322 	mei_enable_interrupts(dev);
323 
324 	ret = mei_txe_aliveness_set_sync(dev, 1);
325 
326 	mutex_unlock(&dev->device_lock);
327 
328 	dev_dbg(&pdev->dev, "rpm: txe: runtime resume ret = %d\n", ret);
329 
330 	if (ret)
331 		schedule_work(&dev->reset_work);
332 
333 	return ret;
334 }
335 
336 /**
337  * mei_txe_set_pm_domain - fill and set pm domain structure for device
338  *
339  * @dev: mei_device
340  */
341 static inline void mei_txe_set_pm_domain(struct mei_device *dev)
342 {
343 	struct pci_dev *pdev  = to_pci_dev(dev->dev);
344 
345 	if (pdev->dev.bus && pdev->dev.bus->pm) {
346 		dev->pg_domain.ops = *pdev->dev.bus->pm;
347 
348 		dev->pg_domain.ops.runtime_suspend = mei_txe_pm_runtime_suspend;
349 		dev->pg_domain.ops.runtime_resume = mei_txe_pm_runtime_resume;
350 		dev->pg_domain.ops.runtime_idle = mei_txe_pm_runtime_idle;
351 
352 		dev_pm_domain_set(&pdev->dev, &dev->pg_domain);
353 	}
354 }
355 
356 /**
357  * mei_txe_unset_pm_domain - clean pm domain structure for device
358  *
359  * @dev: mei_device
360  */
361 static inline void mei_txe_unset_pm_domain(struct mei_device *dev)
362 {
363 	/* stop using pm callbacks if any */
364 	dev_pm_domain_set(dev->dev, NULL);
365 }
366 
367 static const struct dev_pm_ops mei_txe_pm_ops = {
368 	SET_SYSTEM_SLEEP_PM_OPS(mei_txe_pci_suspend,
369 				mei_txe_pci_resume)
370 	SET_RUNTIME_PM_OPS(
371 		mei_txe_pm_runtime_suspend,
372 		mei_txe_pm_runtime_resume,
373 		mei_txe_pm_runtime_idle)
374 };
375 
376 #define MEI_TXE_PM_OPS	(&mei_txe_pm_ops)
377 #else
378 #define MEI_TXE_PM_OPS	NULL
379 #endif /* CONFIG_PM */
380 
381 /*
382  *  PCI driver structure
383  */
384 static struct pci_driver mei_txe_driver = {
385 	.name = KBUILD_MODNAME,
386 	.id_table = mei_txe_pci_tbl,
387 	.probe = mei_txe_probe,
388 	.remove = mei_txe_remove,
389 	.shutdown = mei_txe_remove,
390 	.driver.pm = MEI_TXE_PM_OPS,
391 };
392 
393 module_pci_driver(mei_txe_driver);
394 
395 MODULE_AUTHOR("Intel Corporation");
396 MODULE_DESCRIPTION("Intel(R) Trusted Execution Environment Interface");
397 MODULE_LICENSE("GPL v2");
398