]> asedeno.scripts.mit.edu Git - linux.git/blob - drivers/thermal/intel/intel_pch_thermal.c
zram: fix race between backing_dev_show and backing_dev_store
[linux.git] / drivers / thermal / intel / intel_pch_thermal.c
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/module.h>
11 #include <linux/types.h>
12 #include <linux/init.h>
13 #include <linux/pci.h>
14 #include <linux/acpi.h>
15 #include <linux/thermal.h>
16 #include <linux/pm.h>
17
18 /* Intel PCH thermal Device IDs */
19 #define PCH_THERMAL_DID_HSW_1   0x9C24 /* Haswell PCH */
20 #define PCH_THERMAL_DID_HSW_2   0x8C24 /* Haswell PCH */
21 #define PCH_THERMAL_DID_WPT     0x9CA4 /* Wildcat Point */
22 #define PCH_THERMAL_DID_SKL     0x9D31 /* Skylake PCH */
23 #define PCH_THERMAL_DID_SKL_H   0xA131 /* Skylake PCH 100 series */
24 #define PCH_THERMAL_DID_CNL     0x9Df9 /* CNL PCH */
25 #define PCH_THERMAL_DID_CNL_H   0xA379 /* CNL-H PCH */
26
27 /* Wildcat Point-LP  PCH Thermal registers */
28 #define WPT_TEMP        0x0000  /* Temperature */
29 #define WPT_TSC 0x04    /* Thermal Sensor Control */
30 #define WPT_TSS 0x06    /* Thermal Sensor Status */
31 #define WPT_TSEL        0x08    /* Thermal Sensor Enable and Lock */
32 #define WPT_TSREL       0x0A    /* Thermal Sensor Report Enable and Lock */
33 #define WPT_TSMIC       0x0C    /* Thermal Sensor SMI Control */
34 #define WPT_CTT 0x0010  /* Catastrophic Trip Point */
35 #define WPT_TAHV        0x0014  /* Thermal Alert High Value */
36 #define WPT_TALV        0x0018  /* Thermal Alert Low Value */
37 #define WPT_TL          0x00000040      /* Throttle Value */
38 #define WPT_PHL 0x0060  /* PCH Hot Level */
39 #define WPT_PHLC        0x62    /* PHL Control */
40 #define WPT_TAS 0x80    /* Thermal Alert Status */
41 #define WPT_TSPIEN      0x82    /* PCI Interrupt Event Enables */
42 #define WPT_TSGPEN      0x84    /* General Purpose Event Enables */
43
44 /*  Wildcat Point-LP  PCH Thermal Register bit definitions */
45 #define WPT_TEMP_TSR    0x01ff  /* Temp TS Reading */
46 #define WPT_TSC_CPDE    0x01    /* Catastrophic Power-Down Enable */
47 #define WPT_TSS_TSDSS   0x10    /* Thermal Sensor Dynamic Shutdown Status */
48 #define WPT_TSS_GPES    0x08    /* GPE status */
49 #define WPT_TSEL_ETS    0x01    /* Enable TS */
50 #define WPT_TSEL_PLDB   0x80    /* TSEL Policy Lock-Down Bit */
51 #define WPT_TL_TOL      0x000001FF      /* T0 Level */
52 #define WPT_TL_T1L      0x1ff00000      /* T1 Level */
53 #define WPT_TL_TTEN     0x20000000      /* TT Enable */
54
55 static char driver_name[] = "Intel PCH thermal driver";
56
57 struct pch_thermal_device {
58         void __iomem *hw_base;
59         const struct pch_dev_ops *ops;
60         struct pci_dev *pdev;
61         struct thermal_zone_device *tzd;
62         int crt_trip_id;
63         unsigned long crt_temp;
64         int hot_trip_id;
65         unsigned long hot_temp;
66         int psv_trip_id;
67         unsigned long psv_temp;
68         bool bios_enabled;
69 };
70
71 #ifdef CONFIG_ACPI
72
73 /*
74  * On some platforms, there is a companion ACPI device, which adds
75  * passive trip temperature using _PSV method. There is no specific
76  * passive temperature setting in MMIO interface of this PCI device.
77  */
78 static void pch_wpt_add_acpi_psv_trip(struct pch_thermal_device *ptd,
79                                       int *nr_trips)
80 {
81         struct acpi_device *adev;
82
83         ptd->psv_trip_id = -1;
84
85         adev = ACPI_COMPANION(&ptd->pdev->dev);
86         if (adev) {
87                 unsigned long long r;
88                 acpi_status status;
89
90                 status = acpi_evaluate_integer(adev->handle, "_PSV", NULL,
91                                                &r);
92                 if (ACPI_SUCCESS(status)) {
93                         unsigned long trip_temp;
94
95                         trip_temp = DECI_KELVIN_TO_MILLICELSIUS(r);
96                         if (trip_temp) {
97                                 ptd->psv_temp = trip_temp;
98                                 ptd->psv_trip_id = *nr_trips;
99                                 ++(*nr_trips);
100                         }
101                 }
102         }
103 }
104 #else
105 static void pch_wpt_add_acpi_psv_trip(struct pch_thermal_device *ptd,
106                                       int *nr_trips)
107 {
108         ptd->psv_trip_id = -1;
109
110 }
111 #endif
112
113 static int pch_wpt_init(struct pch_thermal_device *ptd, int *nr_trips)
114 {
115         u8 tsel;
116         u16 trip_temp;
117
118         *nr_trips = 0;
119
120         /* Check if BIOS has already enabled thermal sensor */
121         if (WPT_TSEL_ETS & readb(ptd->hw_base + WPT_TSEL)) {
122                 ptd->bios_enabled = true;
123                 goto read_trips;
124         }
125
126         tsel = readb(ptd->hw_base + WPT_TSEL);
127         /*
128          * When TSEL's Policy Lock-Down bit is 1, TSEL become RO.
129          * If so, thermal sensor cannot enable. Bail out.
130          */
131         if (tsel & WPT_TSEL_PLDB) {
132                 dev_err(&ptd->pdev->dev, "Sensor can't be enabled\n");
133                 return -ENODEV;
134         }
135
136         writeb(tsel|WPT_TSEL_ETS, ptd->hw_base + WPT_TSEL);
137         if (!(WPT_TSEL_ETS & readb(ptd->hw_base + WPT_TSEL))) {
138                 dev_err(&ptd->pdev->dev, "Sensor can't be enabled\n");
139                 return -ENODEV;
140         }
141
142 read_trips:
143         ptd->crt_trip_id = -1;
144         trip_temp = readw(ptd->hw_base + WPT_CTT);
145         trip_temp &= 0x1FF;
146         if (trip_temp) {
147                 /* Resolution of 1/2 degree C and an offset of -50C */
148                 ptd->crt_temp = trip_temp * 1000 / 2 - 50000;
149                 ptd->crt_trip_id = 0;
150                 ++(*nr_trips);
151         }
152
153         ptd->hot_trip_id = -1;
154         trip_temp = readw(ptd->hw_base + WPT_PHL);
155         trip_temp &= 0x1FF;
156         if (trip_temp) {
157                 /* Resolution of 1/2 degree C and an offset of -50C */
158                 ptd->hot_temp = trip_temp * 1000 / 2 - 50000;
159                 ptd->hot_trip_id = *nr_trips;
160                 ++(*nr_trips);
161         }
162
163         pch_wpt_add_acpi_psv_trip(ptd, nr_trips);
164
165         return 0;
166 }
167
168 static int pch_wpt_get_temp(struct pch_thermal_device *ptd, int *temp)
169 {
170         u16 wpt_temp;
171
172         wpt_temp = WPT_TEMP_TSR & readw(ptd->hw_base + WPT_TEMP);
173
174         /* Resolution of 1/2 degree C and an offset of -50C */
175         *temp = (wpt_temp * 1000 / 2 - 50000);
176
177         return 0;
178 }
179
180 static int pch_wpt_suspend(struct pch_thermal_device *ptd)
181 {
182         u8 tsel;
183
184         if (ptd->bios_enabled)
185                 return 0;
186
187         tsel = readb(ptd->hw_base + WPT_TSEL);
188
189         writeb(tsel & 0xFE, ptd->hw_base + WPT_TSEL);
190
191         return 0;
192 }
193
194 static int pch_wpt_resume(struct pch_thermal_device *ptd)
195 {
196         u8 tsel;
197
198         if (ptd->bios_enabled)
199                 return 0;
200
201         tsel = readb(ptd->hw_base + WPT_TSEL);
202
203         writeb(tsel | WPT_TSEL_ETS, ptd->hw_base + WPT_TSEL);
204
205         return 0;
206 }
207
208 struct pch_dev_ops {
209         int (*hw_init)(struct pch_thermal_device *ptd, int *nr_trips);
210         int (*get_temp)(struct pch_thermal_device *ptd, int *temp);
211         int (*suspend)(struct pch_thermal_device *ptd);
212         int (*resume)(struct pch_thermal_device *ptd);
213 };
214
215
216 /* dev ops for Wildcat Point */
217 static const struct pch_dev_ops pch_dev_ops_wpt = {
218         .hw_init = pch_wpt_init,
219         .get_temp = pch_wpt_get_temp,
220         .suspend = pch_wpt_suspend,
221         .resume = pch_wpt_resume,
222 };
223
224 static int pch_thermal_get_temp(struct thermal_zone_device *tzd, int *temp)
225 {
226         struct pch_thermal_device *ptd = tzd->devdata;
227
228         return  ptd->ops->get_temp(ptd, temp);
229 }
230
231 static int pch_get_trip_type(struct thermal_zone_device *tzd, int trip,
232                              enum thermal_trip_type *type)
233 {
234         struct pch_thermal_device *ptd = tzd->devdata;
235
236         if (ptd->crt_trip_id == trip)
237                 *type = THERMAL_TRIP_CRITICAL;
238         else if (ptd->hot_trip_id == trip)
239                 *type = THERMAL_TRIP_HOT;
240         else if (ptd->psv_trip_id == trip)
241                 *type = THERMAL_TRIP_PASSIVE;
242         else
243                 return -EINVAL;
244
245         return 0;
246 }
247
248 static int pch_get_trip_temp(struct thermal_zone_device *tzd, int trip, int *temp)
249 {
250         struct pch_thermal_device *ptd = tzd->devdata;
251
252         if (ptd->crt_trip_id == trip)
253                 *temp = ptd->crt_temp;
254         else if (ptd->hot_trip_id == trip)
255                 *temp = ptd->hot_temp;
256         else if (ptd->psv_trip_id == trip)
257                 *temp = ptd->psv_temp;
258         else
259                 return -EINVAL;
260
261         return 0;
262 }
263
264 static struct thermal_zone_device_ops tzd_ops = {
265         .get_temp = pch_thermal_get_temp,
266         .get_trip_type = pch_get_trip_type,
267         .get_trip_temp = pch_get_trip_temp,
268 };
269
270 enum board_ids {
271         board_hsw,
272         board_wpt,
273         board_skl,
274         board_cnl,
275 };
276
277 static const struct board_info {
278         const char *name;
279         const struct pch_dev_ops *ops;
280 } board_info[] = {
281         [board_hsw] = {
282                 .name = "pch_haswell",
283                 .ops = &pch_dev_ops_wpt,
284         },
285         [board_wpt] = {
286                 .name = "pch_wildcat_point",
287                 .ops = &pch_dev_ops_wpt,
288         },
289         [board_skl] = {
290                 .name = "pch_skylake",
291                 .ops = &pch_dev_ops_wpt,
292         },
293         [board_cnl] = {
294                 .name = "pch_cannonlake",
295                 .ops = &pch_dev_ops_wpt,
296         },
297 };
298
299 static int intel_pch_thermal_probe(struct pci_dev *pdev,
300                                    const struct pci_device_id *id)
301 {
302         enum board_ids board_id = id->driver_data;
303         const struct board_info *bi = &board_info[board_id];
304         struct pch_thermal_device *ptd;
305         int err;
306         int nr_trips;
307
308         ptd = devm_kzalloc(&pdev->dev, sizeof(*ptd), GFP_KERNEL);
309         if (!ptd)
310                 return -ENOMEM;
311
312         ptd->ops = bi->ops;
313
314         pci_set_drvdata(pdev, ptd);
315         ptd->pdev = pdev;
316
317         err = pci_enable_device(pdev);
318         if (err) {
319                 dev_err(&pdev->dev, "failed to enable pci device\n");
320                 return err;
321         }
322
323         err = pci_request_regions(pdev, driver_name);
324         if (err) {
325                 dev_err(&pdev->dev, "failed to request pci region\n");
326                 goto error_disable;
327         }
328
329         ptd->hw_base = pci_ioremap_bar(pdev, 0);
330         if (!ptd->hw_base) {
331                 err = -ENOMEM;
332                 dev_err(&pdev->dev, "failed to map mem base\n");
333                 goto error_release;
334         }
335
336         err = ptd->ops->hw_init(ptd, &nr_trips);
337         if (err)
338                 goto error_cleanup;
339
340         ptd->tzd = thermal_zone_device_register(bi->name, nr_trips, 0, ptd,
341                                                 &tzd_ops, NULL, 0, 0);
342         if (IS_ERR(ptd->tzd)) {
343                 dev_err(&pdev->dev, "Failed to register thermal zone %s\n",
344                         bi->name);
345                 err = PTR_ERR(ptd->tzd);
346                 goto error_cleanup;
347         }
348
349         return 0;
350
351 error_cleanup:
352         iounmap(ptd->hw_base);
353 error_release:
354         pci_release_regions(pdev);
355 error_disable:
356         pci_disable_device(pdev);
357         dev_err(&pdev->dev, "pci device failed to probe\n");
358         return err;
359 }
360
361 static void intel_pch_thermal_remove(struct pci_dev *pdev)
362 {
363         struct pch_thermal_device *ptd = pci_get_drvdata(pdev);
364
365         thermal_zone_device_unregister(ptd->tzd);
366         iounmap(ptd->hw_base);
367         pci_set_drvdata(pdev, NULL);
368         pci_release_region(pdev, 0);
369         pci_disable_device(pdev);
370 }
371
372 static int intel_pch_thermal_suspend(struct device *device)
373 {
374         struct pch_thermal_device *ptd = dev_get_drvdata(device);
375
376         return ptd->ops->suspend(ptd);
377 }
378
379 static int intel_pch_thermal_resume(struct device *device)
380 {
381         struct pch_thermal_device *ptd = dev_get_drvdata(device);
382
383         return ptd->ops->resume(ptd);
384 }
385
386 static const struct pci_device_id intel_pch_thermal_id[] = {
387         { PCI_DEVICE(PCI_VENDOR_ID_INTEL, PCH_THERMAL_DID_HSW_1),
388                 .driver_data = board_hsw, },
389         { PCI_DEVICE(PCI_VENDOR_ID_INTEL, PCH_THERMAL_DID_HSW_2),
390                 .driver_data = board_hsw, },
391         { PCI_DEVICE(PCI_VENDOR_ID_INTEL, PCH_THERMAL_DID_WPT),
392                 .driver_data = board_wpt, },
393         { PCI_DEVICE(PCI_VENDOR_ID_INTEL, PCH_THERMAL_DID_SKL),
394                 .driver_data = board_skl, },
395         { PCI_DEVICE(PCI_VENDOR_ID_INTEL, PCH_THERMAL_DID_SKL_H),
396                 .driver_data = board_skl, },
397         { PCI_DEVICE(PCI_VENDOR_ID_INTEL, PCH_THERMAL_DID_CNL),
398                 .driver_data = board_cnl, },
399         { PCI_DEVICE(PCI_VENDOR_ID_INTEL, PCH_THERMAL_DID_CNL_H),
400                 .driver_data = board_cnl, },
401         { 0, },
402 };
403 MODULE_DEVICE_TABLE(pci, intel_pch_thermal_id);
404
405 static const struct dev_pm_ops intel_pch_pm_ops = {
406         .suspend = intel_pch_thermal_suspend,
407         .resume = intel_pch_thermal_resume,
408 };
409
410 static struct pci_driver intel_pch_thermal_driver = {
411         .name           = "intel_pch_thermal",
412         .id_table       = intel_pch_thermal_id,
413         .probe          = intel_pch_thermal_probe,
414         .remove         = intel_pch_thermal_remove,
415         .driver.pm      = &intel_pch_pm_ops,
416 };
417
418 module_pci_driver(intel_pch_thermal_driver);
419
420 MODULE_LICENSE("GPL v2");
421 MODULE_DESCRIPTION("Intel PCH Thermal driver");