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 static inline bool ish_should_leave_d0i3(struct pci_dev *pdev)
110 {
111 	return !pm_resume_via_firmware() || pdev->device == CHV_DEVICE_ID;
112 }
113 
114 /**
115  * ish_probe() - PCI driver probe callback
116  * @pdev:	pci device
117  * @ent:	pci device id
118  *
119  * Initialize PCI function, setup interrupt and call for ISH initialization
120  *
121  * Return: 0 for success or error code for failure
122  */
123 static int ish_probe(struct pci_dev *pdev, const struct pci_device_id *ent)
124 {
125 	int ret;
126 	struct ish_hw *hw;
127 	unsigned long irq_flag = 0;
128 	struct ishtp_device *ishtp;
129 	struct device *dev = &pdev->dev;
130 
131 	/* Check for invalid platforms for ISH support */
132 	if (pci_dev_present(ish_invalid_pci_ids))
133 		return -ENODEV;
134 
135 	/* enable pci dev */
136 	ret = pcim_enable_device(pdev);
137 	if (ret) {
138 		dev_err(dev, "ISH: Failed to enable PCI device\n");
139 		return ret;
140 	}
141 
142 	/* set PCI host mastering */
143 	pci_set_master(pdev);
144 
145 	/* pci request regions for ISH driver */
146 	ret = pcim_iomap_regions(pdev, 1 << 0, KBUILD_MODNAME);
147 	if (ret) {
148 		dev_err(dev, "ISH: Failed to get PCI regions\n");
149 		return ret;
150 	}
151 
152 	/* allocates and initializes the ISH dev structure */
153 	ishtp = ish_dev_init(pdev);
154 	if (!ishtp) {
155 		ret = -ENOMEM;
156 		return ret;
157 	}
158 	hw = to_ish_hw(ishtp);
159 	ishtp->print_log = ish_event_tracer;
160 
161 	/* mapping IO device memory */
162 	hw->mem_addr = pcim_iomap_table(pdev)[0];
163 	ishtp->pdev = pdev;
164 
165 	/* request and enable interrupt */
166 	ret = pci_alloc_irq_vectors(pdev, 1, 1, PCI_IRQ_ALL_TYPES);
167 	if (!pdev->msi_enabled && !pdev->msix_enabled)
168 		irq_flag = IRQF_SHARED;
169 
170 	ret = devm_request_irq(dev, pdev->irq, ish_irq_handler,
171 			       irq_flag, KBUILD_MODNAME, ishtp);
172 	if (ret) {
173 		dev_err(dev, "ISH: request IRQ %d failed\n", pdev->irq);
174 		return ret;
175 	}
176 
177 	dev_set_drvdata(ishtp->devc, ishtp);
178 
179 	init_waitqueue_head(&ishtp->suspend_wait);
180 	init_waitqueue_head(&ishtp->resume_wait);
181 
182 	ret = ish_init(ishtp);
183 	if (ret)
184 		return ret;
185 
186 	return 0;
187 }
188 
189 /**
190  * ish_remove() - PCI driver remove callback
191  * @pdev:	pci device
192  *
193  * This function does cleanup of ISH on pci remove callback
194  */
195 static void ish_remove(struct pci_dev *pdev)
196 {
197 	struct ishtp_device *ishtp_dev = pci_get_drvdata(pdev);
198 
199 	ishtp_bus_remove_all_clients(ishtp_dev, false);
200 	ish_device_disable(ishtp_dev);
201 }
202 
203 static struct device __maybe_unused *ish_resume_device;
204 
205 /* 50ms to get resume response */
206 #define WAIT_FOR_RESUME_ACK_MS		50
207 
208 /**
209  * ish_resume_handler() - Work function to complete resume
210  * @work:	work struct
211  *
212  * The resume work function to complete resume function asynchronously.
213  * There are two resume paths, one where ISH is not powered off,
214  * in that case a simple resume message is enough, others we need
215  * a reset sequence.
216  */
217 static void __maybe_unused ish_resume_handler(struct work_struct *work)
218 {
219 	struct pci_dev *pdev = to_pci_dev(ish_resume_device);
220 	struct ishtp_device *dev = pci_get_drvdata(pdev);
221 	int ret;
222 
223 	if (ish_should_leave_d0i3(pdev) && !dev->suspend_flag) {
224 		disable_irq_wake(pdev->irq);
225 
226 		ishtp_send_resume(dev);
227 
228 		/* Waiting to get resume response */
229 		if (dev->resume_flag)
230 			ret = wait_event_interruptible_timeout(dev->resume_wait,
231 				!dev->resume_flag,
232 				msecs_to_jiffies(WAIT_FOR_RESUME_ACK_MS));
233 
234 		/*
235 		 * If the flag is not cleared, something is wrong with ISH FW.
236 		 * So on resume, need to go through init sequence again.
237 		 */
238 		if (dev->resume_flag)
239 			ish_init(dev);
240 	} else {
241 		/*
242 		 * Resume from the D3, full reboot of ISH processor will happen,
243 		 * so need to go through init sequence again.
244 		 */
245 		ish_init(dev);
246 	}
247 }
248 
249 /**
250  * ish_suspend() - ISH suspend callback
251  * @device:	device pointer
252  *
253  * ISH suspend callback
254  *
255  * Return: 0 to the pm core
256  */
257 static int __maybe_unused ish_suspend(struct device *device)
258 {
259 	struct pci_dev *pdev = to_pci_dev(device);
260 	struct ishtp_device *dev = pci_get_drvdata(pdev);
261 
262 	if (ish_should_enter_d0i3(pdev)) {
263 		/*
264 		 * If previous suspend hasn't been asnwered then ISH is likely
265 		 * dead, don't attempt nested notification
266 		 */
267 		if (dev->suspend_flag)
268 			return	0;
269 
270 		dev->resume_flag = 0;
271 		dev->suspend_flag = 1;
272 		ishtp_send_suspend(dev);
273 
274 		/* 25 ms should be enough for live ISH to flush all IPC buf */
275 		if (dev->suspend_flag)
276 			wait_event_interruptible_timeout(dev->suspend_wait,
277 					!dev->suspend_flag,
278 					msecs_to_jiffies(25));
279 
280 		if (dev->suspend_flag) {
281 			/*
282 			 * It looks like FW halt, clear the DMA bit, and put
283 			 * ISH into D3, and FW would reset on resume.
284 			 */
285 			ish_disable_dma(dev);
286 		} else {
287 			/*
288 			 * Save state so PCI core will keep the device at D0,
289 			 * the ISH would enter D0i3
290 			 */
291 			pci_save_state(pdev);
292 
293 			enable_irq_wake(pdev->irq);
294 		}
295 	} else {
296 		/*
297 		 * Clear the DMA bit before putting ISH into D3,
298 		 * or ISH FW would reset automatically.
299 		 */
300 		ish_disable_dma(dev);
301 	}
302 
303 	return 0;
304 }
305 
306 static __maybe_unused DECLARE_WORK(resume_work, ish_resume_handler);
307 /**
308  * ish_resume() - ISH resume callback
309  * @device:	device pointer
310  *
311  * ISH resume callback
312  *
313  * Return: 0 to the pm core
314  */
315 static int __maybe_unused ish_resume(struct device *device)
316 {
317 	struct pci_dev *pdev = to_pci_dev(device);
318 	struct ishtp_device *dev = pci_get_drvdata(pdev);
319 
320 	ish_resume_device = device;
321 	dev->resume_flag = 1;
322 
323 	schedule_work(&resume_work);
324 
325 	return 0;
326 }
327 
328 static SIMPLE_DEV_PM_OPS(ish_pm_ops, ish_suspend, ish_resume);
329 
330 static struct pci_driver ish_driver = {
331 	.name = KBUILD_MODNAME,
332 	.id_table = ish_pci_tbl,
333 	.probe = ish_probe,
334 	.remove = ish_remove,
335 	.driver.pm = &ish_pm_ops,
336 };
337 
338 module_pci_driver(ish_driver);
339 
340 /* Original author */
341 MODULE_AUTHOR("Daniel Drubin <daniel.drubin@intel.com>");
342 /* Adoption to upstream Linux kernel */
343 MODULE_AUTHOR("Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com>");
344 
345 MODULE_DESCRIPTION("Intel(R) Integrated Sensor Hub PCI Device Driver");
346 MODULE_LICENSE("GPL");
347