1 // SPDX-License-Identifier: GPL-2.0-only
2 /* intel_pch_thermal.c - Intel PCH Thermal driver
3  *
4  * Copyright (c) 2015, Intel Corporation.
5  *
6  * Authors:
7  *     Tushar Dave <tushar.n.dave@intel.com>
8  */
9 
10 #include <linux/acpi.h>
11 #include <linux/delay.h>
12 #include <linux/module.h>
13 #include <linux/init.h>
14 #include <linux/pci.h>
15 #include <linux/pm.h>
16 #include <linux/suspend.h>
17 #include <linux/thermal.h>
18 #include <linux/types.h>
19 #include <linux/units.h>
20 
21 /* Intel PCH thermal Device IDs */
22 #define PCH_THERMAL_DID_HSW_1	0x9C24 /* Haswell PCH */
23 #define PCH_THERMAL_DID_HSW_2	0x8C24 /* Haswell PCH */
24 #define PCH_THERMAL_DID_WPT	0x9CA4 /* Wildcat Point */
25 #define PCH_THERMAL_DID_SKL	0x9D31 /* Skylake PCH */
26 #define PCH_THERMAL_DID_SKL_H	0xA131 /* Skylake PCH 100 series */
27 #define PCH_THERMAL_DID_CNL	0x9Df9 /* CNL PCH */
28 #define PCH_THERMAL_DID_CNL_H	0xA379 /* CNL-H PCH */
29 #define PCH_THERMAL_DID_CNL_LP	0x02F9 /* CNL-LP PCH */
30 #define PCH_THERMAL_DID_CML_H	0X06F9 /* CML-H PCH */
31 #define PCH_THERMAL_DID_LWB	0xA1B1 /* Lewisburg PCH */
32 #define PCH_THERMAL_DID_WBG	0x8D24 /* Wellsburg PCH */
33 
34 /* Wildcat Point-LP  PCH Thermal registers */
35 #define WPT_TEMP	0x0000	/* Temperature */
36 #define WPT_TSC	0x04	/* Thermal Sensor Control */
37 #define WPT_TSS	0x06	/* Thermal Sensor Status */
38 #define WPT_TSEL	0x08	/* Thermal Sensor Enable and Lock */
39 #define WPT_TSREL	0x0A	/* Thermal Sensor Report Enable and Lock */
40 #define WPT_TSMIC	0x0C	/* Thermal Sensor SMI Control */
41 #define WPT_CTT	0x0010	/* Catastrophic Trip Point */
42 #define WPT_TSPM	0x001C	/* Thermal Sensor Power Management */
43 #define WPT_TAHV	0x0014	/* Thermal Alert High Value */
44 #define WPT_TALV	0x0018	/* Thermal Alert Low Value */
45 #define WPT_TL		0x00000040	/* Throttle Value */
46 #define WPT_PHL	0x0060	/* PCH Hot Level */
47 #define WPT_PHLC	0x62	/* PHL Control */
48 #define WPT_TAS	0x80	/* Thermal Alert Status */
49 #define WPT_TSPIEN	0x82	/* PCI Interrupt Event Enables */
50 #define WPT_TSGPEN	0x84	/* General Purpose Event Enables */
51 
52 /*  Wildcat Point-LP  PCH Thermal Register bit definitions */
53 #define WPT_TEMP_TSR	0x01ff	/* Temp TS Reading */
54 #define WPT_TSC_CPDE	0x01	/* Catastrophic Power-Down Enable */
55 #define WPT_TSS_TSDSS	0x10	/* Thermal Sensor Dynamic Shutdown Status */
56 #define WPT_TSS_GPES	0x08	/* GPE status */
57 #define WPT_TSEL_ETS	0x01    /* Enable TS */
58 #define WPT_TSEL_PLDB	0x80	/* TSEL Policy Lock-Down Bit */
59 #define WPT_TL_TOL	0x000001FF	/* T0 Level */
60 #define WPT_TL_T1L	0x1ff00000	/* T1 Level */
61 #define WPT_TL_TTEN	0x20000000	/* TT Enable */
62 
63 /* Resolution of 1/2 degree C and an offset of -50C */
64 #define PCH_TEMP_OFFSET	(-50)
65 #define GET_WPT_TEMP(x)	((x) * MILLIDEGREE_PER_DEGREE / 2 + WPT_TEMP_OFFSET)
66 #define WPT_TEMP_OFFSET	(PCH_TEMP_OFFSET * MILLIDEGREE_PER_DEGREE)
67 #define GET_PCH_TEMP(x)	(((x) / 2) + PCH_TEMP_OFFSET)
68 
69 #define PCH_MAX_TRIPS 3 /* critical, hot, passive */
70 
71 /* Amount of time for each cooling delay, 100ms by default for now */
72 static unsigned int delay_timeout = 100;
73 module_param(delay_timeout, int, 0644);
74 MODULE_PARM_DESC(delay_timeout, "amount of time delay for each iteration.");
75 
76 /* Number of iterations for cooling delay, 600 counts by default for now */
77 static unsigned int delay_cnt = 600;
78 module_param(delay_cnt, int, 0644);
79 MODULE_PARM_DESC(delay_cnt, "total number of iterations for time delay.");
80 
81 static char driver_name[] = "Intel PCH thermal driver";
82 
83 struct pch_thermal_device {
84 	void __iomem *hw_base;
85 	struct pci_dev *pdev;
86 	struct thermal_zone_device *tzd;
87 	struct thermal_trip trips[PCH_MAX_TRIPS];
88 	bool bios_enabled;
89 };
90 
91 #ifdef CONFIG_ACPI
92 /*
93  * On some platforms, there is a companion ACPI device, which adds
94  * passive trip temperature using _PSV method. There is no specific
95  * passive temperature setting in MMIO interface of this PCI device.
96  */
97 static int pch_wpt_add_acpi_psv_trip(struct pch_thermal_device *ptd, int trip)
98 {
99 	struct acpi_device *adev;
100 	int temp;
101 
102 	adev = ACPI_COMPANION(&ptd->pdev->dev);
103 	if (!adev)
104 		return 0;
105 
106 	if (thermal_acpi_passive_trip_temp(adev, &temp) || temp <= 0)
107 		return 0;
108 
109 	ptd->trips[trip].type = THERMAL_TRIP_PASSIVE;
110 	ptd->trips[trip].temperature = temp;
111 	return 1;
112 }
113 #else
114 static int pch_wpt_add_acpi_psv_trip(struct pch_thermal_device *ptd, int trip)
115 {
116 	return 0;
117 }
118 #endif
119 
120 static int pch_thermal_get_temp(struct thermal_zone_device *tzd, int *temp)
121 {
122 	struct pch_thermal_device *ptd = tzd->devdata;
123 
124 	*temp = GET_WPT_TEMP(WPT_TEMP_TSR & readw(ptd->hw_base + WPT_TEMP));
125 	return 0;
126 }
127 
128 static void pch_critical(struct thermal_zone_device *tzd)
129 {
130 	dev_dbg(&tzd->device, "%s: critical temperature reached\n", tzd->type);
131 }
132 
133 static struct thermal_zone_device_ops tzd_ops = {
134 	.get_temp = pch_thermal_get_temp,
135 	.critical = pch_critical,
136 };
137 
138 enum pch_board_ids {
139 	PCH_BOARD_HSW = 0,
140 	PCH_BOARD_WPT,
141 	PCH_BOARD_SKL,
142 	PCH_BOARD_CNL,
143 	PCH_BOARD_CML,
144 	PCH_BOARD_LWB,
145 	PCH_BOARD_WBG,
146 };
147 
148 static const char *board_names[] = {
149 	[PCH_BOARD_HSW] = "pch_haswell",
150 	[PCH_BOARD_WPT] = "pch_wildcat_point",
151 	[PCH_BOARD_SKL] = "pch_skylake",
152 	[PCH_BOARD_CNL] = "pch_cannonlake",
153 	[PCH_BOARD_CML] = "pch_cometlake",
154 	[PCH_BOARD_LWB] = "pch_lewisburg",
155 	[PCH_BOARD_WBG] = "pch_wellsburg",
156 };
157 
158 static int intel_pch_thermal_probe(struct pci_dev *pdev,
159 				   const struct pci_device_id *id)
160 {
161 	enum pch_board_ids board_id = id->driver_data;
162 	struct pch_thermal_device *ptd;
163 	int nr_trips = 0;
164 	u16 trip_temp;
165 	u8 tsel;
166 	int err;
167 
168 	ptd = devm_kzalloc(&pdev->dev, sizeof(*ptd), GFP_KERNEL);
169 	if (!ptd)
170 		return -ENOMEM;
171 
172 	pci_set_drvdata(pdev, ptd);
173 	ptd->pdev = pdev;
174 
175 	err = pci_enable_device(pdev);
176 	if (err) {
177 		dev_err(&pdev->dev, "failed to enable pci device\n");
178 		return err;
179 	}
180 
181 	err = pci_request_regions(pdev, driver_name);
182 	if (err) {
183 		dev_err(&pdev->dev, "failed to request pci region\n");
184 		goto error_disable;
185 	}
186 
187 	ptd->hw_base = pci_ioremap_bar(pdev, 0);
188 	if (!ptd->hw_base) {
189 		err = -ENOMEM;
190 		dev_err(&pdev->dev, "failed to map mem base\n");
191 		goto error_release;
192 	}
193 
194 	/* Check if BIOS has already enabled thermal sensor */
195 	if (WPT_TSEL_ETS & readb(ptd->hw_base + WPT_TSEL)) {
196 		ptd->bios_enabled = true;
197 		goto read_trips;
198 	}
199 
200 	tsel = readb(ptd->hw_base + WPT_TSEL);
201 	/*
202 	 * When TSEL's Policy Lock-Down bit is 1, TSEL become RO.
203 	 * If so, thermal sensor cannot enable. Bail out.
204 	 */
205 	if (tsel & WPT_TSEL_PLDB) {
206 		dev_err(&ptd->pdev->dev, "Sensor can't be enabled\n");
207 		err = -ENODEV;
208 		goto error_cleanup;
209 	}
210 
211 	writeb(tsel|WPT_TSEL_ETS, ptd->hw_base + WPT_TSEL);
212 	if (!(WPT_TSEL_ETS & readb(ptd->hw_base + WPT_TSEL))) {
213 		dev_err(&ptd->pdev->dev, "Sensor can't be enabled\n");
214 		err = -ENODEV;
215 		goto error_cleanup;
216 	}
217 
218 read_trips:
219 	trip_temp = readw(ptd->hw_base + WPT_CTT);
220 	trip_temp &= 0x1FF;
221 	if (trip_temp) {
222 		ptd->trips[nr_trips].temperature = GET_WPT_TEMP(trip_temp);
223 		ptd->trips[nr_trips++].type = THERMAL_TRIP_CRITICAL;
224 	}
225 
226 	trip_temp = readw(ptd->hw_base + WPT_PHL);
227 	trip_temp &= 0x1FF;
228 	if (trip_temp) {
229 		ptd->trips[nr_trips].temperature = GET_WPT_TEMP(trip_temp);
230 		ptd->trips[nr_trips++].type = THERMAL_TRIP_HOT;
231 	}
232 
233 	nr_trips += pch_wpt_add_acpi_psv_trip(ptd, nr_trips);
234 
235 	ptd->tzd = thermal_zone_device_register_with_trips(board_names[board_id],
236 							   ptd->trips, nr_trips,
237 							   0, ptd, &tzd_ops,
238 							   NULL, 0, 0);
239 	if (IS_ERR(ptd->tzd)) {
240 		dev_err(&pdev->dev, "Failed to register thermal zone %s\n",
241 			board_names[board_id]);
242 		err = PTR_ERR(ptd->tzd);
243 		goto error_cleanup;
244 	}
245 	err = thermal_zone_device_enable(ptd->tzd);
246 	if (err)
247 		goto err_unregister;
248 
249 	return 0;
250 
251 err_unregister:
252 	thermal_zone_device_unregister(ptd->tzd);
253 error_cleanup:
254 	iounmap(ptd->hw_base);
255 error_release:
256 	pci_release_regions(pdev);
257 error_disable:
258 	pci_disable_device(pdev);
259 	dev_err(&pdev->dev, "pci device failed to probe\n");
260 	return err;
261 }
262 
263 static void intel_pch_thermal_remove(struct pci_dev *pdev)
264 {
265 	struct pch_thermal_device *ptd = pci_get_drvdata(pdev);
266 
267 	thermal_zone_device_unregister(ptd->tzd);
268 	iounmap(ptd->hw_base);
269 	pci_set_drvdata(pdev, NULL);
270 	pci_release_regions(pdev);
271 	pci_disable_device(pdev);
272 }
273 
274 static int intel_pch_thermal_suspend_noirq(struct device *device)
275 {
276 	struct pch_thermal_device *ptd = dev_get_drvdata(device);
277 	u16 pch_thr_temp, pch_cur_temp;
278 	int pch_delay_cnt = 0;
279 	u8 tsel;
280 
281 	/* Shutdown the thermal sensor if it is not enabled by BIOS */
282 	if (!ptd->bios_enabled) {
283 		tsel = readb(ptd->hw_base + WPT_TSEL);
284 		writeb(tsel & 0xFE, ptd->hw_base + WPT_TSEL);
285 		return 0;
286 	}
287 
288 	/* Do not check temperature if it is not s2idle */
289 	if (pm_suspend_via_firmware())
290 		return 0;
291 
292 	/* Get the PCH temperature threshold value */
293 	pch_thr_temp = GET_PCH_TEMP(WPT_TEMP_TSR & readw(ptd->hw_base + WPT_TSPM));
294 
295 	/* Get the PCH current temperature value */
296 	pch_cur_temp = GET_PCH_TEMP(WPT_TEMP_TSR & readw(ptd->hw_base + WPT_TEMP));
297 
298 	/*
299 	 * If current PCH temperature is higher than configured PCH threshold
300 	 * value, run some delay loop with sleep to let the current temperature
301 	 * go down below the threshold value which helps to allow system enter
302 	 * lower power S0ix suspend state. Even after delay loop if PCH current
303 	 * temperature stays above threshold, notify the warning message
304 	 * which helps to indentify the reason why S0ix entry was rejected.
305 	 */
306 	while (pch_delay_cnt < delay_cnt) {
307 		if (pch_cur_temp < pch_thr_temp)
308 			break;
309 
310 		if (pm_wakeup_pending()) {
311 			dev_warn(&ptd->pdev->dev, "Wakeup event detected, abort cooling\n");
312 			return 0;
313 		}
314 
315 		pch_delay_cnt++;
316 		dev_dbg(&ptd->pdev->dev,
317 			"CPU-PCH current temp [%dC] higher than the threshold temp [%dC], sleep %d times for %d ms duration\n",
318 			pch_cur_temp, pch_thr_temp, pch_delay_cnt, delay_timeout);
319 		msleep(delay_timeout);
320 		/* Read the PCH current temperature for next cycle. */
321 		pch_cur_temp = GET_PCH_TEMP(WPT_TEMP_TSR & readw(ptd->hw_base + WPT_TEMP));
322 	}
323 
324 	if (pch_cur_temp >= pch_thr_temp)
325 		dev_warn(&ptd->pdev->dev,
326 			"CPU-PCH is hot [%dC] after %d ms delay. S0ix might fail\n",
327 			pch_cur_temp, pch_delay_cnt * delay_timeout);
328 	else {
329 		if (pch_delay_cnt)
330 			dev_info(&ptd->pdev->dev,
331 				"CPU-PCH is cool [%dC] after %d ms delay\n",
332 				pch_cur_temp, pch_delay_cnt * delay_timeout);
333 		else
334 			dev_info(&ptd->pdev->dev,
335 				"CPU-PCH is cool [%dC]\n",
336 				pch_cur_temp);
337 	}
338 
339 	return 0;
340 }
341 
342 static int intel_pch_thermal_resume(struct device *device)
343 {
344 	struct pch_thermal_device *ptd = dev_get_drvdata(device);
345 	u8 tsel;
346 
347 	if (ptd->bios_enabled)
348 		return 0;
349 
350 	tsel = readb(ptd->hw_base + WPT_TSEL);
351 
352 	writeb(tsel | WPT_TSEL_ETS, ptd->hw_base + WPT_TSEL);
353 
354 	return 0;
355 }
356 
357 static const struct pci_device_id intel_pch_thermal_id[] = {
358 	{ PCI_DEVICE(PCI_VENDOR_ID_INTEL, PCH_THERMAL_DID_HSW_1),
359 		.driver_data = PCH_BOARD_HSW, },
360 	{ PCI_DEVICE(PCI_VENDOR_ID_INTEL, PCH_THERMAL_DID_HSW_2),
361 		.driver_data = PCH_BOARD_HSW, },
362 	{ PCI_DEVICE(PCI_VENDOR_ID_INTEL, PCH_THERMAL_DID_WPT),
363 		.driver_data = PCH_BOARD_WPT, },
364 	{ PCI_DEVICE(PCI_VENDOR_ID_INTEL, PCH_THERMAL_DID_SKL),
365 		.driver_data = PCH_BOARD_SKL, },
366 	{ PCI_DEVICE(PCI_VENDOR_ID_INTEL, PCH_THERMAL_DID_SKL_H),
367 		.driver_data = PCH_BOARD_SKL, },
368 	{ PCI_DEVICE(PCI_VENDOR_ID_INTEL, PCH_THERMAL_DID_CNL),
369 		.driver_data = PCH_BOARD_CNL, },
370 	{ PCI_DEVICE(PCI_VENDOR_ID_INTEL, PCH_THERMAL_DID_CNL_H),
371 		.driver_data = PCH_BOARD_CNL, },
372 	{ PCI_DEVICE(PCI_VENDOR_ID_INTEL, PCH_THERMAL_DID_CNL_LP),
373 		.driver_data = PCH_BOARD_CNL, },
374 	{ PCI_DEVICE(PCI_VENDOR_ID_INTEL, PCH_THERMAL_DID_CML_H),
375 		.driver_data = PCH_BOARD_CML, },
376 	{ PCI_DEVICE(PCI_VENDOR_ID_INTEL, PCH_THERMAL_DID_LWB),
377 		.driver_data = PCH_BOARD_LWB, },
378 	{ PCI_DEVICE(PCI_VENDOR_ID_INTEL, PCH_THERMAL_DID_WBG),
379 		.driver_data = PCH_BOARD_WBG, },
380 	{ 0, },
381 };
382 MODULE_DEVICE_TABLE(pci, intel_pch_thermal_id);
383 
384 static const struct dev_pm_ops intel_pch_pm_ops = {
385 	.suspend_noirq = intel_pch_thermal_suspend_noirq,
386 	.resume = intel_pch_thermal_resume,
387 };
388 
389 static struct pci_driver intel_pch_thermal_driver = {
390 	.name		= "intel_pch_thermal",
391 	.id_table	= intel_pch_thermal_id,
392 	.probe		= intel_pch_thermal_probe,
393 	.remove		= intel_pch_thermal_remove,
394 	.driver.pm	= &intel_pch_pm_ops,
395 };
396 
397 module_pci_driver(intel_pch_thermal_driver);
398 
399 MODULE_LICENSE("GPL v2");
400 MODULE_DESCRIPTION("Intel PCH Thermal driver");
401