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, CMP_H_DEVICE_ID)},
38 	{PCI_DEVICE(PCI_VENDOR_ID_INTEL, EHL_Ax_DEVICE_ID)},
39 	{PCI_DEVICE(PCI_VENDOR_ID_INTEL, TGL_LP_DEVICE_ID)},
40 	{0, }
41 };
42 MODULE_DEVICE_TABLE(pci, ish_pci_tbl);
43 
44 /**
45  * ish_event_tracer() - Callback function to dump trace messages
46  * @dev:	ishtp device
47  * @format:	printf style format
48  *
49  * Callback to direct log messages to Linux trace buffers
50  */
51 static __printf(2, 3)
52 void ish_event_tracer(struct ishtp_device *dev, const char *format, ...)
53 {
54 	if (trace_ishtp_dump_enabled()) {
55 		va_list args;
56 		char tmp_buf[100];
57 
58 		va_start(args, format);
59 		vsnprintf(tmp_buf, sizeof(tmp_buf), format, args);
60 		va_end(args);
61 
62 		trace_ishtp_dump(tmp_buf);
63 	}
64 }
65 
66 /**
67  * ish_init() - Init function
68  * @dev:	ishtp device
69  *
70  * This function initialize wait queues for suspend/resume and call
71  * calls hadware initialization function. This will initiate
72  * startup sequence
73  *
74  * Return: 0 for success or error code for failure
75  */
76 static int ish_init(struct ishtp_device *dev)
77 {
78 	int ret;
79 
80 	/* Set the state of ISH HW to start */
81 	ret = ish_hw_start(dev);
82 	if (ret) {
83 		dev_err(dev->devc, "ISH: hw start failed.\n");
84 		return ret;
85 	}
86 
87 	/* Start the inter process communication to ISH processor */
88 	ret = ishtp_start(dev);
89 	if (ret) {
90 		dev_err(dev->devc, "ISHTP: Protocol init failed.\n");
91 		return ret;
92 	}
93 
94 	return 0;
95 }
96 
97 static const struct pci_device_id ish_invalid_pci_ids[] = {
98 	/* Mehlow platform special pci ids */
99 	{PCI_DEVICE(PCI_VENDOR_ID_INTEL, 0xA309)},
100 	{PCI_DEVICE(PCI_VENDOR_ID_INTEL, 0xA30A)},
101 	{}
102 };
103 
104 static inline bool ish_should_enter_d0i3(struct pci_dev *pdev)
105 {
106 	return !pm_suspend_via_firmware() || pdev->device == CHV_DEVICE_ID;
107 }
108 
109 /**
110  * ish_probe() - PCI driver probe callback
111  * @pdev:	pci device
112  * @ent:	pci device id
113  *
114  * Initialize PCI function, setup interrupt and call for ISH initialization
115  *
116  * Return: 0 for success or error code for failure
117  */
118 static int ish_probe(struct pci_dev *pdev, const struct pci_device_id *ent)
119 {
120 	int ret;
121 	struct ish_hw *hw;
122 	unsigned long irq_flag = 0;
123 	struct ishtp_device *ishtp;
124 	struct device *dev = &pdev->dev;
125 
126 	/* Check for invalid platforms for ISH support */
127 	if (pci_dev_present(ish_invalid_pci_ids))
128 		return -ENODEV;
129 
130 	/* enable pci dev */
131 	ret = pcim_enable_device(pdev);
132 	if (ret) {
133 		dev_err(dev, "ISH: Failed to enable PCI device\n");
134 		return ret;
135 	}
136 
137 	/* set PCI host mastering */
138 	pci_set_master(pdev);
139 
140 	/* pci request regions for ISH driver */
141 	ret = pcim_iomap_regions(pdev, 1 << 0, KBUILD_MODNAME);
142 	if (ret) {
143 		dev_err(dev, "ISH: Failed to get PCI regions\n");
144 		return ret;
145 	}
146 
147 	/* allocates and initializes the ISH dev structure */
148 	ishtp = ish_dev_init(pdev);
149 	if (!ishtp) {
150 		ret = -ENOMEM;
151 		return ret;
152 	}
153 	hw = to_ish_hw(ishtp);
154 	ishtp->print_log = ish_event_tracer;
155 
156 	/* mapping IO device memory */
157 	hw->mem_addr = pcim_iomap_table(pdev)[0];
158 	ishtp->pdev = pdev;
159 
160 	/* request and enable interrupt */
161 	ret = pci_alloc_irq_vectors(pdev, 1, 1, PCI_IRQ_ALL_TYPES);
162 	if (!pdev->msi_enabled && !pdev->msix_enabled)
163 		irq_flag = IRQF_SHARED;
164 
165 	ret = devm_request_irq(dev, pdev->irq, ish_irq_handler,
166 			       irq_flag, KBUILD_MODNAME, ishtp);
167 	if (ret) {
168 		dev_err(dev, "ISH: request IRQ %d failed\n", pdev->irq);
169 		return ret;
170 	}
171 
172 	dev_set_drvdata(ishtp->devc, ishtp);
173 
174 	init_waitqueue_head(&ishtp->suspend_wait);
175 	init_waitqueue_head(&ishtp->resume_wait);
176 
177 	ret = ish_init(ishtp);
178 	if (ret)
179 		return ret;
180 
181 	return 0;
182 }
183 
184 /**
185  * ish_remove() - PCI driver remove callback
186  * @pdev:	pci device
187  *
188  * This function does cleanup of ISH on pci remove callback
189  */
190 static void ish_remove(struct pci_dev *pdev)
191 {
192 	struct ishtp_device *ishtp_dev = pci_get_drvdata(pdev);
193 
194 	ishtp_bus_remove_all_clients(ishtp_dev, false);
195 	ish_device_disable(ishtp_dev);
196 }
197 
198 static struct device __maybe_unused *ish_resume_device;
199 
200 /* 50ms to get resume response */
201 #define WAIT_FOR_RESUME_ACK_MS		50
202 
203 /**
204  * ish_resume_handler() - Work function to complete resume
205  * @work:	work struct
206  *
207  * The resume work function to complete resume function asynchronously.
208  * There are two resume paths, one where ISH is not powered off,
209  * in that case a simple resume message is enough, others we need
210  * a reset sequence.
211  */
212 static void __maybe_unused ish_resume_handler(struct work_struct *work)
213 {
214 	struct pci_dev *pdev = to_pci_dev(ish_resume_device);
215 	struct ishtp_device *dev = pci_get_drvdata(pdev);
216 	int ret;
217 
218 	/* Check the NO_D3 flag to distinguish the resume paths */
219 	if (pdev->dev_flags & PCI_DEV_FLAGS_NO_D3) {
220 		pdev->dev_flags &= ~PCI_DEV_FLAGS_NO_D3;
221 		disable_irq_wake(pdev->irq);
222 
223 		ishtp_send_resume(dev);
224 
225 		/* Waiting to get resume response */
226 		if (dev->resume_flag)
227 			ret = wait_event_interruptible_timeout(dev->resume_wait,
228 				!dev->resume_flag,
229 				msecs_to_jiffies(WAIT_FOR_RESUME_ACK_MS));
230 
231 		/*
232 		 * If the flag is not cleared, something is wrong with ISH FW.
233 		 * So on resume, need to go through init sequence again.
234 		 */
235 		if (dev->resume_flag)
236 			ish_init(dev);
237 	} else {
238 		/*
239 		 * Resume from the D3, full reboot of ISH processor will happen,
240 		 * so need to go through init sequence again.
241 		 */
242 		ish_init(dev);
243 	}
244 }
245 
246 /**
247  * ish_suspend() - ISH suspend callback
248  * @device:	device pointer
249  *
250  * ISH suspend callback
251  *
252  * Return: 0 to the pm core
253  */
254 static int __maybe_unused ish_suspend(struct device *device)
255 {
256 	struct pci_dev *pdev = to_pci_dev(device);
257 	struct ishtp_device *dev = pci_get_drvdata(pdev);
258 
259 	if (ish_should_enter_d0i3(pdev)) {
260 		/*
261 		 * If previous suspend hasn't been asnwered then ISH is likely
262 		 * dead, don't attempt nested notification
263 		 */
264 		if (dev->suspend_flag)
265 			return	0;
266 
267 		dev->resume_flag = 0;
268 		dev->suspend_flag = 1;
269 		ishtp_send_suspend(dev);
270 
271 		/* 25 ms should be enough for live ISH to flush all IPC buf */
272 		if (dev->suspend_flag)
273 			wait_event_interruptible_timeout(dev->suspend_wait,
274 					!dev->suspend_flag,
275 					msecs_to_jiffies(25));
276 
277 		if (dev->suspend_flag) {
278 			/*
279 			 * It looks like FW halt, clear the DMA bit, and put
280 			 * ISH into D3, and FW would reset on resume.
281 			 */
282 			ish_disable_dma(dev);
283 		} else {
284 			/* Set the NO_D3 flag, the ISH would enter D0i3 */
285 			pdev->dev_flags |= PCI_DEV_FLAGS_NO_D3;
286 
287 			enable_irq_wake(pdev->irq);
288 		}
289 	} else {
290 		/*
291 		 * Clear the DMA bit before putting ISH into D3,
292 		 * or ISH FW would reset automatically.
293 		 */
294 		ish_disable_dma(dev);
295 	}
296 
297 	return 0;
298 }
299 
300 static __maybe_unused DECLARE_WORK(resume_work, ish_resume_handler);
301 /**
302  * ish_resume() - ISH resume callback
303  * @device:	device pointer
304  *
305  * ISH resume callback
306  *
307  * Return: 0 to the pm core
308  */
309 static int __maybe_unused ish_resume(struct device *device)
310 {
311 	struct pci_dev *pdev = to_pci_dev(device);
312 	struct ishtp_device *dev = pci_get_drvdata(pdev);
313 
314 	ish_resume_device = device;
315 	dev->resume_flag = 1;
316 
317 	schedule_work(&resume_work);
318 
319 	return 0;
320 }
321 
322 static SIMPLE_DEV_PM_OPS(ish_pm_ops, ish_suspend, ish_resume);
323 
324 static struct pci_driver ish_driver = {
325 	.name = KBUILD_MODNAME,
326 	.id_table = ish_pci_tbl,
327 	.probe = ish_probe,
328 	.remove = ish_remove,
329 	.driver.pm = &ish_pm_ops,
330 };
331 
332 module_pci_driver(ish_driver);
333 
334 /* Original author */
335 MODULE_AUTHOR("Daniel Drubin <daniel.drubin@intel.com>");
336 /* Adoption to upstream Linux kernel */
337 MODULE_AUTHOR("Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com>");
338 
339 MODULE_DESCRIPTION("Intel(R) Integrated Sensor Hub PCI Device Driver");
340 MODULE_LICENSE("GPL");
341