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
mei_txe_set_pm_domain(struct mei_device * dev)38 static inline void mei_txe_set_pm_domain(struct mei_device *dev) {}
mei_txe_unset_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 */
mei_txe_probe(struct pci_dev * pdev,const struct pci_device_id * ent)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 = dma_set_mask(&pdev->dev, DMA_BIT_MASK(36));
73 if (err) {
74 err = dma_set_mask(&pdev->dev, 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 err = mei_register(dev, &pdev->dev);
91 if (err)
92 goto end;
93
94 pci_enable_msi(pdev);
95
96 /* clear spurious interrupts */
97 mei_clear_interrupts(dev);
98
99 /* request and enable interrupt */
100 if (pci_dev_msi_enabled(pdev))
101 err = request_threaded_irq(pdev->irq,
102 NULL,
103 mei_txe_irq_thread_handler,
104 IRQF_ONESHOT, KBUILD_MODNAME, dev);
105 else
106 err = request_threaded_irq(pdev->irq,
107 mei_txe_irq_quick_handler,
108 mei_txe_irq_thread_handler,
109 IRQF_SHARED, KBUILD_MODNAME, dev);
110 if (err) {
111 dev_err(&pdev->dev, "mei: request_threaded_irq failure. irq = %d\n",
112 pdev->irq);
113 goto deregister;
114 }
115
116 if (mei_start(dev)) {
117 dev_err(&pdev->dev, "init hw failure.\n");
118 err = -ENODEV;
119 goto deregister;
120 }
121
122 pm_runtime_set_autosuspend_delay(&pdev->dev, MEI_TXI_RPM_TIMEOUT);
123 pm_runtime_use_autosuspend(&pdev->dev);
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 deregister:
148 mei_cancel_work(dev);
149 mei_disable_interrupts(dev);
150 free_irq(pdev->irq, dev);
151 mei_deregister(dev);
152 end:
153 dev_err(&pdev->dev, "initialization failed.\n");
154 return err;
155 }
156
157 /**
158 * mei_txe_shutdown- Device Shutdown Routine
159 *
160 * @pdev: PCI device structure
161 *
162 * mei_txe_shutdown is called from the reboot notifier
163 * it's a simplified version of remove so we go down
164 * faster.
165 */
mei_txe_shutdown(struct pci_dev * pdev)166 static void mei_txe_shutdown(struct pci_dev *pdev)
167 {
168 struct mei_device *dev = pci_get_drvdata(pdev);
169
170 dev_dbg(&pdev->dev, "shutdown\n");
171 mei_stop(dev);
172
173 mei_txe_unset_pm_domain(dev);
174
175 mei_disable_interrupts(dev);
176 free_irq(pdev->irq, dev);
177 }
178
179 /**
180 * mei_txe_remove - Device Removal Routine
181 *
182 * @pdev: PCI device structure
183 *
184 * mei_remove is called by the PCI subsystem to alert the driver
185 * that it should release a PCI device.
186 */
mei_txe_remove(struct pci_dev * pdev)187 static void mei_txe_remove(struct pci_dev *pdev)
188 {
189 struct mei_device *dev = pci_get_drvdata(pdev);
190
191 pm_runtime_get_noresume(&pdev->dev);
192
193 mei_stop(dev);
194
195 mei_txe_unset_pm_domain(dev);
196
197 mei_disable_interrupts(dev);
198 free_irq(pdev->irq, dev);
199
200 mei_deregister(dev);
201 }
202
203
204 #ifdef CONFIG_PM_SLEEP
mei_txe_pci_suspend(struct device * device)205 static int mei_txe_pci_suspend(struct device *device)
206 {
207 struct pci_dev *pdev = to_pci_dev(device);
208 struct mei_device *dev = pci_get_drvdata(pdev);
209
210 dev_dbg(&pdev->dev, "suspend\n");
211
212 mei_stop(dev);
213
214 mei_disable_interrupts(dev);
215
216 free_irq(pdev->irq, dev);
217 pci_disable_msi(pdev);
218
219 return 0;
220 }
221
mei_txe_pci_resume(struct device * device)222 static int mei_txe_pci_resume(struct device *device)
223 {
224 struct pci_dev *pdev = to_pci_dev(device);
225 struct mei_device *dev = pci_get_drvdata(pdev);
226 int err;
227
228 pci_enable_msi(pdev);
229
230 mei_clear_interrupts(dev);
231
232 /* request and enable interrupt */
233 if (pci_dev_msi_enabled(pdev))
234 err = request_threaded_irq(pdev->irq,
235 NULL,
236 mei_txe_irq_thread_handler,
237 IRQF_ONESHOT, KBUILD_MODNAME, dev);
238 else
239 err = request_threaded_irq(pdev->irq,
240 mei_txe_irq_quick_handler,
241 mei_txe_irq_thread_handler,
242 IRQF_SHARED, KBUILD_MODNAME, dev);
243 if (err) {
244 dev_err(&pdev->dev, "request_threaded_irq failed: irq = %d.\n",
245 pdev->irq);
246 return err;
247 }
248
249 err = mei_restart(dev);
250
251 return err;
252 }
253 #endif /* CONFIG_PM_SLEEP */
254
255 #ifdef CONFIG_PM
mei_txe_pm_runtime_idle(struct device * device)256 static int mei_txe_pm_runtime_idle(struct device *device)
257 {
258 struct mei_device *dev = dev_get_drvdata(device);
259
260 dev_dbg(device, "rpm: txe: runtime_idle\n");
261
262 if (mei_write_is_idle(dev))
263 pm_runtime_autosuspend(device);
264
265 return -EBUSY;
266 }
mei_txe_pm_runtime_suspend(struct device * device)267 static int mei_txe_pm_runtime_suspend(struct device *device)
268 {
269 struct mei_device *dev = dev_get_drvdata(device);
270 int ret;
271
272 dev_dbg(device, "rpm: txe: runtime suspend\n");
273
274 mutex_lock(&dev->device_lock);
275
276 if (mei_write_is_idle(dev))
277 ret = mei_txe_aliveness_set_sync(dev, 0);
278 else
279 ret = -EAGAIN;
280
281 /* keep irq on we are staying in D0 */
282
283 dev_dbg(device, "rpm: txe: runtime suspend ret=%d\n", ret);
284
285 mutex_unlock(&dev->device_lock);
286
287 if (ret && ret != -EAGAIN)
288 schedule_work(&dev->reset_work);
289
290 return ret;
291 }
292
mei_txe_pm_runtime_resume(struct device * device)293 static int mei_txe_pm_runtime_resume(struct device *device)
294 {
295 struct mei_device *dev = dev_get_drvdata(device);
296 int ret;
297
298 dev_dbg(device, "rpm: txe: runtime resume\n");
299
300 mutex_lock(&dev->device_lock);
301
302 mei_enable_interrupts(dev);
303
304 ret = mei_txe_aliveness_set_sync(dev, 1);
305
306 mutex_unlock(&dev->device_lock);
307
308 dev_dbg(device, "rpm: txe: runtime resume ret = %d\n", ret);
309
310 if (ret)
311 schedule_work(&dev->reset_work);
312
313 return ret;
314 }
315
316 /**
317 * mei_txe_set_pm_domain - fill and set pm domain structure for device
318 *
319 * @dev: mei_device
320 */
mei_txe_set_pm_domain(struct mei_device * dev)321 static inline void mei_txe_set_pm_domain(struct mei_device *dev)
322 {
323 struct pci_dev *pdev = to_pci_dev(dev->parent);
324
325 if (pdev->dev.bus && pdev->dev.bus->pm) {
326 dev->pg_domain.ops = *pdev->dev.bus->pm;
327
328 dev->pg_domain.ops.runtime_suspend = mei_txe_pm_runtime_suspend;
329 dev->pg_domain.ops.runtime_resume = mei_txe_pm_runtime_resume;
330 dev->pg_domain.ops.runtime_idle = mei_txe_pm_runtime_idle;
331
332 dev_pm_domain_set(&pdev->dev, &dev->pg_domain);
333 }
334 }
335
336 /**
337 * mei_txe_unset_pm_domain - clean pm domain structure for device
338 *
339 * @dev: mei_device
340 */
mei_txe_unset_pm_domain(struct mei_device * dev)341 static inline void mei_txe_unset_pm_domain(struct mei_device *dev)
342 {
343 /* stop using pm callbacks if any */
344 dev_pm_domain_set(dev->parent, NULL);
345 }
346
347 static const struct dev_pm_ops mei_txe_pm_ops = {
348 SET_SYSTEM_SLEEP_PM_OPS(mei_txe_pci_suspend,
349 mei_txe_pci_resume)
350 SET_RUNTIME_PM_OPS(
351 mei_txe_pm_runtime_suspend,
352 mei_txe_pm_runtime_resume,
353 mei_txe_pm_runtime_idle)
354 };
355
356 #define MEI_TXE_PM_OPS (&mei_txe_pm_ops)
357 #else
358 #define MEI_TXE_PM_OPS NULL
359 #endif /* CONFIG_PM */
360
361 /*
362 * PCI driver structure
363 */
364 static struct pci_driver mei_txe_driver = {
365 .name = KBUILD_MODNAME,
366 .id_table = mei_txe_pci_tbl,
367 .probe = mei_txe_probe,
368 .remove = mei_txe_remove,
369 .shutdown = mei_txe_shutdown,
370 .driver.pm = MEI_TXE_PM_OPS,
371 };
372
373 module_pci_driver(mei_txe_driver);
374
375 MODULE_AUTHOR("Intel Corporation");
376 MODULE_DESCRIPTION("Intel(R) Trusted Execution Environment Interface");
377 MODULE_LICENSE("GPL v2");
378