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
25static 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};
42MODULE_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 */
51static __printf(2, 3)
52void 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 */
76static 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
97static 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
104static inline bool ish_should_enter_d0i3(struct pci_dev *pdev)
105{
106	return !pm_suspend_via_firmware() || pdev->device == CHV_DEVICE_ID;
107}
108
109static 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 */
123static 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 */
195static 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
203static 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 */
217static 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 */
257static 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
306static __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 */
315static 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
328static SIMPLE_DEV_PM_OPS(ish_pm_ops, ish_suspend, ish_resume);
329
330static 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
338module_pci_driver(ish_driver);
339
340/* Original author */
341MODULE_AUTHOR("Daniel Drubin <daniel.drubin@intel.com>");
342/* Adoption to upstream Linux kernel */
343MODULE_AUTHOR("Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com>");
344
345MODULE_DESCRIPTION("Intel(R) Integrated Sensor Hub PCI Device Driver");
346MODULE_LICENSE("GPL");
347