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 	bool bios_enabled;
88 };
89 
90 #ifdef CONFIG_ACPI
91 /*
92  * On some platforms, there is a companion ACPI device, which adds
93  * passive trip temperature using _PSV method. There is no specific
94  * passive temperature setting in MMIO interface of this PCI device.
95  */
96 static int pch_wpt_add_acpi_psv_trip(struct pch_thermal_device *ptd,
97 				     struct thermal_trip *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 	trip->type = THERMAL_TRIP_PASSIVE;
110 	trip->temperature = temp;
111 	return 1;
112 }
113 #else
114 static int pch_wpt_add_acpi_psv_trip(struct pch_thermal_device *ptd,
115 				     struct thermal_trip *trip)
116 {
117 	return 0;
118 }
119 #endif
120 
121 static int pch_thermal_get_temp(struct thermal_zone_device *tzd, int *temp)
122 {
123 	struct pch_thermal_device *ptd = thermal_zone_device_priv(tzd);
124 
125 	*temp = GET_WPT_TEMP(WPT_TEMP_TSR & readw(ptd->hw_base + WPT_TEMP));
126 	return 0;
127 }
128 
129 static void pch_critical(struct thermal_zone_device *tzd)
130 {
131 	dev_dbg(thermal_zone_device(tzd), "%s: critical temperature reached\n",
132 		thermal_zone_device_type(tzd));
133 }
134 
135 static const struct thermal_zone_device_ops tzd_ops = {
136 	.get_temp = pch_thermal_get_temp,
137 	.critical = pch_critical,
138 };
139 
140 enum pch_board_ids {
141 	PCH_BOARD_HSW = 0,
142 	PCH_BOARD_WPT,
143 	PCH_BOARD_SKL,
144 	PCH_BOARD_CNL,
145 	PCH_BOARD_CML,
146 	PCH_BOARD_LWB,
147 	PCH_BOARD_WBG,
148 };
149 
150 static const char *board_names[] = {
151 	[PCH_BOARD_HSW] = "pch_haswell",
152 	[PCH_BOARD_WPT] = "pch_wildcat_point",
153 	[PCH_BOARD_SKL] = "pch_skylake",
154 	[PCH_BOARD_CNL] = "pch_cannonlake",
155 	[PCH_BOARD_CML] = "pch_cometlake",
156 	[PCH_BOARD_LWB] = "pch_lewisburg",
157 	[PCH_BOARD_WBG] = "pch_wellsburg",
158 };
159 
160 static int intel_pch_thermal_probe(struct pci_dev *pdev,
161 				   const struct pci_device_id *id)
162 {
163 	struct thermal_trip ptd_trips[PCH_MAX_TRIPS] = { 0 };
164 	enum pch_board_ids board_id = id->driver_data;
165 	struct pch_thermal_device *ptd;
166 	int nr_trips = 0;
167 	u16 trip_temp;
168 	u8 tsel;
169 	int err;
170 
171 	ptd = devm_kzalloc(&pdev->dev, sizeof(*ptd), GFP_KERNEL);
172 	if (!ptd)
173 		return -ENOMEM;
174 
175 	pci_set_drvdata(pdev, ptd);
176 	ptd->pdev = pdev;
177 
178 	err = pci_enable_device(pdev);
179 	if (err) {
180 		dev_err(&pdev->dev, "failed to enable pci device\n");
181 		return err;
182 	}
183 
184 	err = pci_request_regions(pdev, driver_name);
185 	if (err) {
186 		dev_err(&pdev->dev, "failed to request pci region\n");
187 		goto error_disable;
188 	}
189 
190 	ptd->hw_base = pci_ioremap_bar(pdev, 0);
191 	if (!ptd->hw_base) {
192 		err = -ENOMEM;
193 		dev_err(&pdev->dev, "failed to map mem base\n");
194 		goto error_release;
195 	}
196 
197 	/* Check if BIOS has already enabled thermal sensor */
198 	if (WPT_TSEL_ETS & readb(ptd->hw_base + WPT_TSEL)) {
199 		ptd->bios_enabled = true;
200 		goto read_trips;
201 	}
202 
203 	tsel = readb(ptd->hw_base + WPT_TSEL);
204 	/*
205 	 * When TSEL's Policy Lock-Down bit is 1, TSEL become RO.
206 	 * If so, thermal sensor cannot enable. Bail out.
207 	 */
208 	if (tsel & WPT_TSEL_PLDB) {
209 		dev_err(&ptd->pdev->dev, "Sensor can't be enabled\n");
210 		err = -ENODEV;
211 		goto error_cleanup;
212 	}
213 
214 	writeb(tsel|WPT_TSEL_ETS, ptd->hw_base + WPT_TSEL);
215 	if (!(WPT_TSEL_ETS & readb(ptd->hw_base + WPT_TSEL))) {
216 		dev_err(&ptd->pdev->dev, "Sensor can't be enabled\n");
217 		err = -ENODEV;
218 		goto error_cleanup;
219 	}
220 
221 read_trips:
222 	trip_temp = readw(ptd->hw_base + WPT_CTT);
223 	trip_temp &= 0x1FF;
224 	if (trip_temp) {
225 		ptd_trips[nr_trips].temperature = GET_WPT_TEMP(trip_temp);
226 		ptd_trips[nr_trips++].type = THERMAL_TRIP_CRITICAL;
227 	}
228 
229 	trip_temp = readw(ptd->hw_base + WPT_PHL);
230 	trip_temp &= 0x1FF;
231 	if (trip_temp) {
232 		ptd_trips[nr_trips].temperature = GET_WPT_TEMP(trip_temp);
233 		ptd_trips[nr_trips++].type = THERMAL_TRIP_HOT;
234 	}
235 
236 	nr_trips += pch_wpt_add_acpi_psv_trip(ptd, &ptd_trips[nr_trips]);
237 
238 	ptd->tzd = thermal_zone_device_register_with_trips(board_names[board_id],
239 							   ptd_trips, nr_trips,
240 							   ptd, &tzd_ops,
241 							   NULL, 0, 0);
242 	if (IS_ERR(ptd->tzd)) {
243 		dev_err(&pdev->dev, "Failed to register thermal zone %s\n",
244 			board_names[board_id]);
245 		err = PTR_ERR(ptd->tzd);
246 		goto error_cleanup;
247 	}
248 	err = thermal_zone_device_enable(ptd->tzd);
249 	if (err)
250 		goto err_unregister;
251 
252 	return 0;
253 
254 err_unregister:
255 	thermal_zone_device_unregister(ptd->tzd);
256 error_cleanup:
257 	iounmap(ptd->hw_base);
258 error_release:
259 	pci_release_regions(pdev);
260 error_disable:
261 	pci_disable_device(pdev);
262 	dev_err(&pdev->dev, "pci device failed to probe\n");
263 	return err;
264 }
265 
266 static void intel_pch_thermal_remove(struct pci_dev *pdev)
267 {
268 	struct pch_thermal_device *ptd = pci_get_drvdata(pdev);
269 
270 	thermal_zone_device_unregister(ptd->tzd);
271 	iounmap(ptd->hw_base);
272 	pci_set_drvdata(pdev, NULL);
273 	pci_release_regions(pdev);
274 	pci_disable_device(pdev);
275 }
276 
277 static int intel_pch_thermal_suspend_noirq(struct device *device)
278 {
279 	struct pch_thermal_device *ptd = dev_get_drvdata(device);
280 	u16 pch_thr_temp, pch_cur_temp;
281 	int pch_delay_cnt = 0;
282 	u8 tsel;
283 
284 	/* Shutdown the thermal sensor if it is not enabled by BIOS */
285 	if (!ptd->bios_enabled) {
286 		tsel = readb(ptd->hw_base + WPT_TSEL);
287 		writeb(tsel & 0xFE, ptd->hw_base + WPT_TSEL);
288 		return 0;
289 	}
290 
291 	/* Do not check temperature if it is not s2idle */
292 	if (pm_suspend_via_firmware())
293 		return 0;
294 
295 	/* Get the PCH temperature threshold value */
296 	pch_thr_temp = GET_PCH_TEMP(WPT_TEMP_TSR & readw(ptd->hw_base + WPT_TSPM));
297 
298 	/* Get the PCH current temperature value */
299 	pch_cur_temp = GET_PCH_TEMP(WPT_TEMP_TSR & readw(ptd->hw_base + WPT_TEMP));
300 
301 	/*
302 	 * If current PCH temperature is higher than configured PCH threshold
303 	 * value, run some delay loop with sleep to let the current temperature
304 	 * go down below the threshold value which helps to allow system enter
305 	 * lower power S0ix suspend state. Even after delay loop if PCH current
306 	 * temperature stays above threshold, notify the warning message
307 	 * which helps to indentify the reason why S0ix entry was rejected.
308 	 */
309 	while (pch_delay_cnt < delay_cnt) {
310 		if (pch_cur_temp < pch_thr_temp)
311 			break;
312 
313 		if (pm_wakeup_pending()) {
314 			dev_warn(&ptd->pdev->dev, "Wakeup event detected, abort cooling\n");
315 			return 0;
316 		}
317 
318 		pch_delay_cnt++;
319 		dev_dbg(&ptd->pdev->dev,
320 			"CPU-PCH current temp [%dC] higher than the threshold temp [%dC], sleep %d times for %d ms duration\n",
321 			pch_cur_temp, pch_thr_temp, pch_delay_cnt, delay_timeout);
322 		msleep(delay_timeout);
323 		/* Read the PCH current temperature for next cycle. */
324 		pch_cur_temp = GET_PCH_TEMP(WPT_TEMP_TSR & readw(ptd->hw_base + WPT_TEMP));
325 	}
326 
327 	if (pch_cur_temp >= pch_thr_temp)
328 		dev_warn(&ptd->pdev->dev,
329 			"CPU-PCH is hot [%dC] after %d ms delay. S0ix might fail\n",
330 			pch_cur_temp, pch_delay_cnt * delay_timeout);
331 	else {
332 		if (pch_delay_cnt)
333 			dev_info(&ptd->pdev->dev,
334 				"CPU-PCH is cool [%dC] after %d ms delay\n",
335 				pch_cur_temp, pch_delay_cnt * delay_timeout);
336 		else
337 			dev_info(&ptd->pdev->dev,
338 				"CPU-PCH is cool [%dC]\n",
339 				pch_cur_temp);
340 	}
341 
342 	return 0;
343 }
344 
345 static int intel_pch_thermal_resume(struct device *device)
346 {
347 	struct pch_thermal_device *ptd = dev_get_drvdata(device);
348 	u8 tsel;
349 
350 	if (ptd->bios_enabled)
351 		return 0;
352 
353 	tsel = readb(ptd->hw_base + WPT_TSEL);
354 
355 	writeb(tsel | WPT_TSEL_ETS, ptd->hw_base + WPT_TSEL);
356 
357 	return 0;
358 }
359 
360 static const struct pci_device_id intel_pch_thermal_id[] = {
361 	{ PCI_DEVICE(PCI_VENDOR_ID_INTEL, PCH_THERMAL_DID_HSW_1),
362 		.driver_data = PCH_BOARD_HSW, },
363 	{ PCI_DEVICE(PCI_VENDOR_ID_INTEL, PCH_THERMAL_DID_HSW_2),
364 		.driver_data = PCH_BOARD_HSW, },
365 	{ PCI_DEVICE(PCI_VENDOR_ID_INTEL, PCH_THERMAL_DID_WPT),
366 		.driver_data = PCH_BOARD_WPT, },
367 	{ PCI_DEVICE(PCI_VENDOR_ID_INTEL, PCH_THERMAL_DID_SKL),
368 		.driver_data = PCH_BOARD_SKL, },
369 	{ PCI_DEVICE(PCI_VENDOR_ID_INTEL, PCH_THERMAL_DID_SKL_H),
370 		.driver_data = PCH_BOARD_SKL, },
371 	{ PCI_DEVICE(PCI_VENDOR_ID_INTEL, PCH_THERMAL_DID_CNL),
372 		.driver_data = PCH_BOARD_CNL, },
373 	{ PCI_DEVICE(PCI_VENDOR_ID_INTEL, PCH_THERMAL_DID_CNL_H),
374 		.driver_data = PCH_BOARD_CNL, },
375 	{ PCI_DEVICE(PCI_VENDOR_ID_INTEL, PCH_THERMAL_DID_CNL_LP),
376 		.driver_data = PCH_BOARD_CNL, },
377 	{ PCI_DEVICE(PCI_VENDOR_ID_INTEL, PCH_THERMAL_DID_CML_H),
378 		.driver_data = PCH_BOARD_CML, },
379 	{ PCI_DEVICE(PCI_VENDOR_ID_INTEL, PCH_THERMAL_DID_LWB),
380 		.driver_data = PCH_BOARD_LWB, },
381 	{ PCI_DEVICE(PCI_VENDOR_ID_INTEL, PCH_THERMAL_DID_WBG),
382 		.driver_data = PCH_BOARD_WBG, },
383 	{ 0, },
384 };
385 MODULE_DEVICE_TABLE(pci, intel_pch_thermal_id);
386 
387 static const struct dev_pm_ops intel_pch_pm_ops = {
388 	.suspend_noirq = intel_pch_thermal_suspend_noirq,
389 	.resume = intel_pch_thermal_resume,
390 };
391 
392 static struct pci_driver intel_pch_thermal_driver = {
393 	.name		= "intel_pch_thermal",
394 	.id_table	= intel_pch_thermal_id,
395 	.probe		= intel_pch_thermal_probe,
396 	.remove		= intel_pch_thermal_remove,
397 	.driver.pm	= &intel_pch_pm_ops,
398 };
399 
400 module_pci_driver(intel_pch_thermal_driver);
401 
402 MODULE_LICENSE("GPL v2");
403 MODULE_DESCRIPTION("Intel PCH Thermal driver");
404