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
26static 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};
32MODULE_DEVICE_TABLE(pci, mei_txe_pci_tbl);
33
34#ifdef CONFIG_PM
35static inline void mei_txe_set_pm_domain(struct mei_device *dev);
36static inline void mei_txe_unset_pm_domain(struct mei_device *dev);
37#else
38static inline void mei_txe_set_pm_domain(struct mei_device *dev) {}
39static 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 */
50static 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(dev: 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(dev: &pdev->dev, DMA_BIT_MASK(36));
73 if (err) {
74 err = dma_set_mask(dev: &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 pci_enable_msi(dev: pdev);
91
92 /* clear spurious interrupts */
93 mei_clear_interrupts(dev);
94
95 /* request and enable interrupt */
96 if (pci_dev_msi_enabled(pci_dev: pdev))
97 err = request_threaded_irq(irq: pdev->irq,
98 NULL,
99 thread_fn: mei_txe_irq_thread_handler,
100 IRQF_ONESHOT, KBUILD_MODNAME, dev);
101 else
102 err = request_threaded_irq(irq: pdev->irq,
103 handler: mei_txe_irq_quick_handler,
104 thread_fn: 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(dev: &pdev->dev, MEI_TXI_RPM_TIMEOUT);
119 pm_runtime_use_autosuspend(dev: &pdev->dev);
120
121 err = mei_register(dev, parent: &pdev->dev);
122 if (err)
123 goto stop;
124
125 pci_set_drvdata(pdev, data: 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(dev: &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(dev: &pdev->dev);
144
145 return 0;
146
147stop:
148 mei_stop(dev);
149release_irq:
150 mei_cancel_work(dev);
151 mei_disable_interrupts(dev);
152 free_irq(pdev->irq, dev);
153end:
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 */
167static void mei_txe_shutdown(struct pci_dev *pdev)
168{
169 struct mei_device *dev = pci_get_drvdata(pdev);
170
171 dev_dbg(&pdev->dev, "shutdown\n");
172 mei_stop(dev);
173
174 mei_txe_unset_pm_domain(dev);
175
176 mei_disable_interrupts(dev);
177 free_irq(pdev->irq, dev);
178}
179
180/**
181 * mei_txe_remove - Device Removal Routine
182 *
183 * @pdev: PCI device structure
184 *
185 * mei_remove is called by the PCI subsystem to alert the driver
186 * that it should release a PCI device.
187 */
188static void mei_txe_remove(struct pci_dev *pdev)
189{
190 struct mei_device *dev = pci_get_drvdata(pdev);
191
192 pm_runtime_get_noresume(dev: &pdev->dev);
193
194 mei_stop(dev);
195
196 mei_txe_unset_pm_domain(dev);
197
198 mei_disable_interrupts(dev);
199 free_irq(pdev->irq, dev);
200
201 mei_deregister(dev);
202}
203
204
205#ifdef CONFIG_PM_SLEEP
206static int mei_txe_pci_suspend(struct device *device)
207{
208 struct pci_dev *pdev = to_pci_dev(device);
209 struct mei_device *dev = pci_get_drvdata(pdev);
210
211 dev_dbg(&pdev->dev, "suspend\n");
212
213 mei_stop(dev);
214
215 mei_disable_interrupts(dev);
216
217 free_irq(pdev->irq, dev);
218 pci_disable_msi(dev: pdev);
219
220 return 0;
221}
222
223static int mei_txe_pci_resume(struct device *device)
224{
225 struct pci_dev *pdev = to_pci_dev(device);
226 struct mei_device *dev = pci_get_drvdata(pdev);
227 int err;
228
229 pci_enable_msi(dev: pdev);
230
231 mei_clear_interrupts(dev);
232
233 /* request and enable interrupt */
234 if (pci_dev_msi_enabled(pci_dev: pdev))
235 err = request_threaded_irq(irq: pdev->irq,
236 NULL,
237 thread_fn: mei_txe_irq_thread_handler,
238 IRQF_ONESHOT, KBUILD_MODNAME, dev);
239 else
240 err = request_threaded_irq(irq: pdev->irq,
241 handler: mei_txe_irq_quick_handler,
242 thread_fn: mei_txe_irq_thread_handler,
243 IRQF_SHARED, KBUILD_MODNAME, dev);
244 if (err) {
245 dev_err(&pdev->dev, "request_threaded_irq failed: irq = %d.\n",
246 pdev->irq);
247 return err;
248 }
249
250 err = mei_restart(dev);
251
252 return err;
253}
254#endif /* CONFIG_PM_SLEEP */
255
256#ifdef CONFIG_PM
257static int mei_txe_pm_runtime_idle(struct device *device)
258{
259 struct mei_device *dev = dev_get_drvdata(dev: device);
260
261 dev_dbg(device, "rpm: txe: runtime_idle\n");
262
263 if (mei_write_is_idle(dev))
264 pm_runtime_autosuspend(dev: device);
265
266 return -EBUSY;
267}
268static int mei_txe_pm_runtime_suspend(struct device *device)
269{
270 struct mei_device *dev = dev_get_drvdata(dev: device);
271 int ret;
272
273 dev_dbg(device, "rpm: txe: runtime suspend\n");
274
275 mutex_lock(&dev->device_lock);
276
277 if (mei_write_is_idle(dev))
278 ret = mei_txe_aliveness_set_sync(dev, req: 0);
279 else
280 ret = -EAGAIN;
281
282 /* keep irq on we are staying in D0 */
283
284 dev_dbg(device, "rpm: txe: runtime suspend ret=%d\n", ret);
285
286 mutex_unlock(lock: &dev->device_lock);
287
288 if (ret && ret != -EAGAIN)
289 schedule_work(work: &dev->reset_work);
290
291 return ret;
292}
293
294static int mei_txe_pm_runtime_resume(struct device *device)
295{
296 struct mei_device *dev = dev_get_drvdata(dev: device);
297 int ret;
298
299 dev_dbg(device, "rpm: txe: runtime resume\n");
300
301 mutex_lock(&dev->device_lock);
302
303 mei_enable_interrupts(dev);
304
305 ret = mei_txe_aliveness_set_sync(dev, req: 1);
306
307 mutex_unlock(lock: &dev->device_lock);
308
309 dev_dbg(device, "rpm: txe: runtime resume ret = %d\n", ret);
310
311 if (ret)
312 schedule_work(work: &dev->reset_work);
313
314 return ret;
315}
316
317/**
318 * mei_txe_set_pm_domain - fill and set pm domain structure for device
319 *
320 * @dev: mei_device
321 */
322static inline void mei_txe_set_pm_domain(struct mei_device *dev)
323{
324 struct pci_dev *pdev = to_pci_dev(dev->dev);
325
326 if (pdev->dev.bus && pdev->dev.bus->pm) {
327 dev->pg_domain.ops = *pdev->dev.bus->pm;
328
329 dev->pg_domain.ops.runtime_suspend = mei_txe_pm_runtime_suspend;
330 dev->pg_domain.ops.runtime_resume = mei_txe_pm_runtime_resume;
331 dev->pg_domain.ops.runtime_idle = mei_txe_pm_runtime_idle;
332
333 dev_pm_domain_set(dev: &pdev->dev, pd: &dev->pg_domain);
334 }
335}
336
337/**
338 * mei_txe_unset_pm_domain - clean pm domain structure for device
339 *
340 * @dev: mei_device
341 */
342static inline void mei_txe_unset_pm_domain(struct mei_device *dev)
343{
344 /* stop using pm callbacks if any */
345 dev_pm_domain_set(dev: dev->dev, NULL);
346}
347
348static const struct dev_pm_ops mei_txe_pm_ops = {
349 SET_SYSTEM_SLEEP_PM_OPS(mei_txe_pci_suspend,
350 mei_txe_pci_resume)
351 SET_RUNTIME_PM_OPS(
352 mei_txe_pm_runtime_suspend,
353 mei_txe_pm_runtime_resume,
354 mei_txe_pm_runtime_idle)
355};
356
357#define MEI_TXE_PM_OPS (&mei_txe_pm_ops)
358#else
359#define MEI_TXE_PM_OPS NULL
360#endif /* CONFIG_PM */
361
362/*
363 * PCI driver structure
364 */
365static struct pci_driver mei_txe_driver = {
366 .name = KBUILD_MODNAME,
367 .id_table = mei_txe_pci_tbl,
368 .probe = mei_txe_probe,
369 .remove = mei_txe_remove,
370 .shutdown = mei_txe_shutdown,
371 .driver.pm = MEI_TXE_PM_OPS,
372};
373
374module_pci_driver(mei_txe_driver);
375
376MODULE_AUTHOR("Intel Corporation");
377MODULE_DESCRIPTION("Intel(R) Trusted Execution Environment Interface");
378MODULE_LICENSE("GPL v2");
379

source code of linux/drivers/misc/mei/pci-txe.c