1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * PCI glue for ISHTP provider device (ISH) driver
4  *
5  * Copyright (c) 2014-2016, Intel Corporation.
6  */
7 
8 #include <linux/module.h>
9 #include <linux/moduleparam.h>
10 #include <linux/kernel.h>
11 #include <linux/device.h>
12 #include <linux/fs.h>
13 #include <linux/errno.h>
14 #include <linux/types.h>
15 #include <linux/pci.h>
16 #include <linux/sched.h>
17 #include <linux/suspend.h>
18 #include <linux/interrupt.h>
19 #include <linux/workqueue.h>
20 #define CREATE_TRACE_POINTS
21 #include <trace/events/intel_ish.h>
22 #include "ishtp-dev.h"
23 #include "hw-ish.h"
24 
25 static const struct pci_device_id ish_pci_tbl[] = {
26 	{PCI_DEVICE(PCI_VENDOR_ID_INTEL, CHV_DEVICE_ID)},
27 	{PCI_DEVICE(PCI_VENDOR_ID_INTEL, BXT_Ax_DEVICE_ID)},
28 	{PCI_DEVICE(PCI_VENDOR_ID_INTEL, BXT_Bx_DEVICE_ID)},
29 	{PCI_DEVICE(PCI_VENDOR_ID_INTEL, APL_Ax_DEVICE_ID)},
30 	{PCI_DEVICE(PCI_VENDOR_ID_INTEL, SPT_Ax_DEVICE_ID)},
31 	{PCI_DEVICE(PCI_VENDOR_ID_INTEL, CNL_Ax_DEVICE_ID)},
32 	{PCI_DEVICE(PCI_VENDOR_ID_INTEL, GLK_Ax_DEVICE_ID)},
33 	{PCI_DEVICE(PCI_VENDOR_ID_INTEL, CNL_H_DEVICE_ID)},
34 	{PCI_DEVICE(PCI_VENDOR_ID_INTEL, ICL_MOBILE_DEVICE_ID)},
35 	{PCI_DEVICE(PCI_VENDOR_ID_INTEL, SPT_H_DEVICE_ID)},
36 	{PCI_DEVICE(PCI_VENDOR_ID_INTEL, CML_LP_DEVICE_ID)},
37 	{PCI_DEVICE(PCI_VENDOR_ID_INTEL, EHL_Ax_DEVICE_ID)},
38 	{0, }
39 };
40 MODULE_DEVICE_TABLE(pci, ish_pci_tbl);
41 
42 /**
43  * ish_event_tracer() - Callback function to dump trace messages
44  * @dev:	ishtp device
45  * @format:	printf style format
46  *
47  * Callback to direct log messages to Linux trace buffers
48  */
49 static __printf(2, 3)
50 void ish_event_tracer(struct ishtp_device *dev, const char *format, ...)
51 {
52 	if (trace_ishtp_dump_enabled()) {
53 		va_list args;
54 		char tmp_buf[100];
55 
56 		va_start(args, format);
57 		vsnprintf(tmp_buf, sizeof(tmp_buf), format, args);
58 		va_end(args);
59 
60 		trace_ishtp_dump(tmp_buf);
61 	}
62 }
63 
64 /**
65  * ish_init() - Init function
66  * @dev:	ishtp device
67  *
68  * This function initialize wait queues for suspend/resume and call
69  * calls hadware initialization function. This will initiate
70  * startup sequence
71  *
72  * Return: 0 for success or error code for failure
73  */
74 static int ish_init(struct ishtp_device *dev)
75 {
76 	int ret;
77 
78 	/* Set the state of ISH HW to start */
79 	ret = ish_hw_start(dev);
80 	if (ret) {
81 		dev_err(dev->devc, "ISH: hw start failed.\n");
82 		return ret;
83 	}
84 
85 	/* Start the inter process communication to ISH processor */
86 	ret = ishtp_start(dev);
87 	if (ret) {
88 		dev_err(dev->devc, "ISHTP: Protocol init failed.\n");
89 		return ret;
90 	}
91 
92 	return 0;
93 }
94 
95 static const struct pci_device_id ish_invalid_pci_ids[] = {
96 	/* Mehlow platform special pci ids */
97 	{PCI_DEVICE(PCI_VENDOR_ID_INTEL, 0xA309)},
98 	{PCI_DEVICE(PCI_VENDOR_ID_INTEL, 0xA30A)},
99 	{}
100 };
101 
102 static inline bool ish_should_enter_d0i3(struct pci_dev *pdev)
103 {
104 	return !pm_suspend_via_firmware() || pdev->device == CHV_DEVICE_ID;
105 }
106 
107 /**
108  * ish_probe() - PCI driver probe callback
109  * @pdev:	pci device
110  * @ent:	pci device id
111  *
112  * Initialize PCI function, setup interrupt and call for ISH initialization
113  *
114  * Return: 0 for success or error code for failure
115  */
116 static int ish_probe(struct pci_dev *pdev, const struct pci_device_id *ent)
117 {
118 	int ret;
119 	struct ish_hw *hw;
120 	unsigned long irq_flag = 0;
121 	struct ishtp_device *ishtp;
122 	struct device *dev = &pdev->dev;
123 
124 	/* Check for invalid platforms for ISH support */
125 	if (pci_dev_present(ish_invalid_pci_ids))
126 		return -ENODEV;
127 
128 	/* enable pci dev */
129 	ret = pcim_enable_device(pdev);
130 	if (ret) {
131 		dev_err(dev, "ISH: Failed to enable PCI device\n");
132 		return ret;
133 	}
134 
135 	/* set PCI host mastering */
136 	pci_set_master(pdev);
137 
138 	/* pci request regions for ISH driver */
139 	ret = pcim_iomap_regions(pdev, 1 << 0, KBUILD_MODNAME);
140 	if (ret) {
141 		dev_err(dev, "ISH: Failed to get PCI regions\n");
142 		return ret;
143 	}
144 
145 	/* allocates and initializes the ISH dev structure */
146 	ishtp = ish_dev_init(pdev);
147 	if (!ishtp) {
148 		ret = -ENOMEM;
149 		return ret;
150 	}
151 	hw = to_ish_hw(ishtp);
152 	ishtp->print_log = ish_event_tracer;
153 
154 	/* mapping IO device memory */
155 	hw->mem_addr = pcim_iomap_table(pdev)[0];
156 	ishtp->pdev = pdev;
157 
158 	/* request and enable interrupt */
159 	ret = pci_alloc_irq_vectors(pdev, 1, 1, PCI_IRQ_ALL_TYPES);
160 	if (!pdev->msi_enabled && !pdev->msix_enabled)
161 		irq_flag = IRQF_SHARED;
162 
163 	ret = devm_request_irq(dev, pdev->irq, ish_irq_handler,
164 			       irq_flag, KBUILD_MODNAME, ishtp);
165 	if (ret) {
166 		dev_err(dev, "ISH: request IRQ %d failed\n", pdev->irq);
167 		return ret;
168 	}
169 
170 	dev_set_drvdata(ishtp->devc, ishtp);
171 
172 	init_waitqueue_head(&ishtp->suspend_wait);
173 	init_waitqueue_head(&ishtp->resume_wait);
174 
175 	ret = ish_init(ishtp);
176 	if (ret)
177 		return ret;
178 
179 	return 0;
180 }
181 
182 /**
183  * ish_remove() - PCI driver remove callback
184  * @pdev:	pci device
185  *
186  * This function does cleanup of ISH on pci remove callback
187  */
188 static void ish_remove(struct pci_dev *pdev)
189 {
190 	struct ishtp_device *ishtp_dev = pci_get_drvdata(pdev);
191 
192 	ishtp_bus_remove_all_clients(ishtp_dev, false);
193 	ish_device_disable(ishtp_dev);
194 }
195 
196 static struct device __maybe_unused *ish_resume_device;
197 
198 /* 50ms to get resume response */
199 #define WAIT_FOR_RESUME_ACK_MS		50
200 
201 /**
202  * ish_resume_handler() - Work function to complete resume
203  * @work:	work struct
204  *
205  * The resume work function to complete resume function asynchronously.
206  * There are two resume paths, one where ISH is not powered off,
207  * in that case a simple resume message is enough, others we need
208  * a reset sequence.
209  */
210 static void __maybe_unused ish_resume_handler(struct work_struct *work)
211 {
212 	struct pci_dev *pdev = to_pci_dev(ish_resume_device);
213 	struct ishtp_device *dev = pci_get_drvdata(pdev);
214 	int ret;
215 
216 	/* Check the NO_D3 flag to distinguish the resume paths */
217 	if (pdev->dev_flags & PCI_DEV_FLAGS_NO_D3) {
218 		pdev->dev_flags &= ~PCI_DEV_FLAGS_NO_D3;
219 		disable_irq_wake(pdev->irq);
220 
221 		ishtp_send_resume(dev);
222 
223 		/* Waiting to get resume response */
224 		if (dev->resume_flag)
225 			ret = wait_event_interruptible_timeout(dev->resume_wait,
226 				!dev->resume_flag,
227 				msecs_to_jiffies(WAIT_FOR_RESUME_ACK_MS));
228 
229 		/*
230 		 * If the flag is not cleared, something is wrong with ISH FW.
231 		 * So on resume, need to go through init sequence again.
232 		 */
233 		if (dev->resume_flag)
234 			ish_init(dev);
235 	} else {
236 		/*
237 		 * Resume from the D3, full reboot of ISH processor will happen,
238 		 * so need to go through init sequence again.
239 		 */
240 		ish_init(dev);
241 	}
242 }
243 
244 /**
245  * ish_suspend() - ISH suspend callback
246  * @device:	device pointer
247  *
248  * ISH suspend callback
249  *
250  * Return: 0 to the pm core
251  */
252 static int __maybe_unused ish_suspend(struct device *device)
253 {
254 	struct pci_dev *pdev = to_pci_dev(device);
255 	struct ishtp_device *dev = pci_get_drvdata(pdev);
256 
257 	if (ish_should_enter_d0i3(pdev)) {
258 		/*
259 		 * If previous suspend hasn't been asnwered then ISH is likely
260 		 * dead, don't attempt nested notification
261 		 */
262 		if (dev->suspend_flag)
263 			return	0;
264 
265 		dev->resume_flag = 0;
266 		dev->suspend_flag = 1;
267 		ishtp_send_suspend(dev);
268 
269 		/* 25 ms should be enough for live ISH to flush all IPC buf */
270 		if (dev->suspend_flag)
271 			wait_event_interruptible_timeout(dev->suspend_wait,
272 					!dev->suspend_flag,
273 					msecs_to_jiffies(25));
274 
275 		if (dev->suspend_flag) {
276 			/*
277 			 * It looks like FW halt, clear the DMA bit, and put
278 			 * ISH into D3, and FW would reset on resume.
279 			 */
280 			ish_disable_dma(dev);
281 		} else {
282 			/* Set the NO_D3 flag, the ISH would enter D0i3 */
283 			pdev->dev_flags |= PCI_DEV_FLAGS_NO_D3;
284 
285 			enable_irq_wake(pdev->irq);
286 		}
287 	} else {
288 		/*
289 		 * Clear the DMA bit before putting ISH into D3,
290 		 * or ISH FW would reset automatically.
291 		 */
292 		ish_disable_dma(dev);
293 	}
294 
295 	return 0;
296 }
297 
298 static __maybe_unused DECLARE_WORK(resume_work, ish_resume_handler);
299 /**
300  * ish_resume() - ISH resume callback
301  * @device:	device pointer
302  *
303  * ISH resume callback
304  *
305  * Return: 0 to the pm core
306  */
307 static int __maybe_unused ish_resume(struct device *device)
308 {
309 	struct pci_dev *pdev = to_pci_dev(device);
310 	struct ishtp_device *dev = pci_get_drvdata(pdev);
311 
312 	ish_resume_device = device;
313 	dev->resume_flag = 1;
314 
315 	schedule_work(&resume_work);
316 
317 	return 0;
318 }
319 
320 static SIMPLE_DEV_PM_OPS(ish_pm_ops, ish_suspend, ish_resume);
321 
322 static struct pci_driver ish_driver = {
323 	.name = KBUILD_MODNAME,
324 	.id_table = ish_pci_tbl,
325 	.probe = ish_probe,
326 	.remove = ish_remove,
327 	.driver.pm = &ish_pm_ops,
328 };
329 
330 module_pci_driver(ish_driver);
331 
332 /* Original author */
333 MODULE_AUTHOR("Daniel Drubin <daniel.drubin@intel.com>");
334 /* Adoption to upstream Linux kernel */
335 MODULE_AUTHOR("Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com>");
336 
337 MODULE_DESCRIPTION("Intel(R) Integrated Sensor Hub PCI Device Driver");
338 MODULE_LICENSE("GPL");
339