1 /* intel_pch_thermal.c - Intel PCH Thermal driver
2 *
3 * Copyright (c) 2015, Intel Corporation.
4 *
5 * Authors:
6 * Tushar Dave <tushar.n.dave@intel.com>
7 *
8 * This program is free software; you can redistribute it and/or modify it
9 * under the terms and conditions of the GNU General Public License,
10 * version 2, as published by the Free Software Foundation.
11 *
12 * This program is distributed in the hope it will be useful, but WITHOUT
13 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
14 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
15 * more details.
16 *
17 */
18
19 #include <linux/module.h>
20 #include <linux/types.h>
21 #include <linux/init.h>
22 #include <linux/pci.h>
23 #include <linux/thermal.h>
24
25 /* Intel PCH thermal Device IDs */
26 #define PCH_THERMAL_DID_WPT 0x9CA4 /* Wildcat Point */
27
28 /* Wildcat Point-LP PCH Thermal registers */
29 #define WPT_TEMP 0x0000 /* Temperature */
30 #define WPT_TSC 0x04 /* Thermal Sensor Control */
31 #define WPT_TSS 0x06 /* Thermal Sensor Status */
32 #define WPT_TSEL 0x08 /* Thermal Sensor Enable and Lock */
33 #define WPT_TSREL 0x0A /* Thermal Sensor Report Enable and Lock */
34 #define WPT_TSMIC 0x0C /* Thermal Sensor SMI Control */
35 #define WPT_CTT 0x0010 /* Catastrophic Trip Point */
36 #define WPT_TAHV 0x0014 /* Thermal Alert High Value */
37 #define WPT_TALV 0x0018 /* Thermal Alert Low Value */
38 #define WPT_TL 0x00000040 /* Throttle Value */
39 #define WPT_PHL 0x0060 /* PCH Hot Level */
40 #define WPT_PHLC 0x62 /* PHL Control */
41 #define WPT_TAS 0x80 /* Thermal Alert Status */
42 #define WPT_TSPIEN 0x82 /* PCI Interrupt Event Enables */
43 #define WPT_TSGPEN 0x84 /* General Purpose Event Enables */
44
45 /* Wildcat Point-LP PCH Thermal Register bit definitions */
46 #define WPT_TEMP_TSR 0x00ff /* Temp TS Reading */
47 #define WPT_TSC_CPDE 0x01 /* Catastrophic Power-Down Enable */
48 #define WPT_TSS_TSDSS 0x10 /* Thermal Sensor Dynamic Shutdown Status */
49 #define WPT_TSS_GPES 0x08 /* GPE status */
50 #define WPT_TSEL_ETS 0x01 /* Enable TS */
51 #define WPT_TSEL_PLDB 0x80 /* TSEL Policy Lock-Down Bit */
52 #define WPT_TL_TOL 0x000001FF /* T0 Level */
53 #define WPT_TL_T1L 0x1ff00000 /* T1 Level */
54 #define WPT_TL_TTEN 0x20000000 /* TT Enable */
55
56 static char driver_name[] = "Intel PCH thermal driver";
57
58 struct pch_thermal_device {
59 void __iomem *hw_base;
60 const struct pch_dev_ops *ops;
61 struct pci_dev *pdev;
62 struct thermal_zone_device *tzd;
63 int crt_trip_id;
64 unsigned long crt_temp;
65 int hot_trip_id;
66 unsigned long hot_temp;
67 };
68
pch_wpt_init(struct pch_thermal_device * ptd,int * nr_trips)69 static int pch_wpt_init(struct pch_thermal_device *ptd, int *nr_trips)
70 {
71 u8 tsel;
72 u16 trip_temp;
73
74 *nr_trips = 0;
75
76 /* Check if BIOS has already enabled thermal sensor */
77 if (WPT_TSS_TSDSS & readb(ptd->hw_base + WPT_TSS))
78 goto read_trips;
79
80 tsel = readb(ptd->hw_base + WPT_TSEL);
81 /*
82 * When TSEL's Policy Lock-Down bit is 1, TSEL become RO.
83 * If so, thermal sensor cannot enable. Bail out.
84 */
85 if (tsel & WPT_TSEL_PLDB) {
86 dev_err(&ptd->pdev->dev, "Sensor can't be enabled\n");
87 return -ENODEV;
88 }
89
90 writeb(tsel|WPT_TSEL_ETS, ptd->hw_base + WPT_TSEL);
91 if (!(WPT_TSS_TSDSS & readb(ptd->hw_base + WPT_TSS))) {
92 dev_err(&ptd->pdev->dev, "Sensor can't be enabled\n");
93 return -ENODEV;
94 }
95
96 read_trips:
97 ptd->crt_trip_id = -1;
98 trip_temp = readw(ptd->hw_base + WPT_CTT);
99 trip_temp &= 0x1FF;
100 if (trip_temp) {
101 /* Resolution of 1/2 degree C and an offset of -50C */
102 ptd->crt_temp = trip_temp * 1000 / 2 - 50000;
103 ptd->crt_trip_id = 0;
104 ++(*nr_trips);
105 }
106
107 ptd->hot_trip_id = -1;
108 trip_temp = readw(ptd->hw_base + WPT_PHL);
109 trip_temp &= 0x1FF;
110 if (trip_temp) {
111 /* Resolution of 1/2 degree C and an offset of -50C */
112 ptd->hot_temp = trip_temp * 1000 / 2 - 50000;
113 ptd->hot_trip_id = *nr_trips;
114 ++(*nr_trips);
115 }
116
117 return 0;
118 }
119
pch_wpt_get_temp(struct pch_thermal_device * ptd,int * temp)120 static int pch_wpt_get_temp(struct pch_thermal_device *ptd, int *temp)
121 {
122 u8 wpt_temp;
123
124 wpt_temp = WPT_TEMP_TSR & readl(ptd->hw_base + WPT_TEMP);
125
126 /* Resolution of 1/2 degree C and an offset of -50C */
127 *temp = (wpt_temp * 1000 / 2 - 50000);
128
129 return 0;
130 }
131
132 struct pch_dev_ops {
133 int (*hw_init)(struct pch_thermal_device *ptd, int *nr_trips);
134 int (*get_temp)(struct pch_thermal_device *ptd, int *temp);
135 };
136
137
138 /* dev ops for Wildcat Point */
139 static struct pch_dev_ops pch_dev_ops_wpt = {
140 .hw_init = pch_wpt_init,
141 .get_temp = pch_wpt_get_temp,
142 };
143
pch_thermal_get_temp(struct thermal_zone_device * tzd,int * temp)144 static int pch_thermal_get_temp(struct thermal_zone_device *tzd, int *temp)
145 {
146 struct pch_thermal_device *ptd = tzd->devdata;
147
148 return ptd->ops->get_temp(ptd, temp);
149 }
150
pch_get_trip_type(struct thermal_zone_device * tzd,int trip,enum thermal_trip_type * type)151 static int pch_get_trip_type(struct thermal_zone_device *tzd, int trip,
152 enum thermal_trip_type *type)
153 {
154 struct pch_thermal_device *ptd = tzd->devdata;
155
156 if (ptd->crt_trip_id == trip)
157 *type = THERMAL_TRIP_CRITICAL;
158 else if (ptd->hot_trip_id == trip)
159 *type = THERMAL_TRIP_HOT;
160 else
161 return -EINVAL;
162
163 return 0;
164 }
165
pch_get_trip_temp(struct thermal_zone_device * tzd,int trip,int * temp)166 static int pch_get_trip_temp(struct thermal_zone_device *tzd, int trip, int *temp)
167 {
168 struct pch_thermal_device *ptd = tzd->devdata;
169
170 if (ptd->crt_trip_id == trip)
171 *temp = ptd->crt_temp;
172 else if (ptd->hot_trip_id == trip)
173 *temp = ptd->hot_temp;
174 else
175 return -EINVAL;
176
177 return 0;
178 }
179
180 static struct thermal_zone_device_ops tzd_ops = {
181 .get_temp = pch_thermal_get_temp,
182 .get_trip_type = pch_get_trip_type,
183 .get_trip_temp = pch_get_trip_temp,
184 };
185
186
intel_pch_thermal_probe(struct pci_dev * pdev,const struct pci_device_id * id)187 static int intel_pch_thermal_probe(struct pci_dev *pdev,
188 const struct pci_device_id *id)
189 {
190 struct pch_thermal_device *ptd;
191 int err;
192 int nr_trips;
193 char *dev_name;
194
195 ptd = devm_kzalloc(&pdev->dev, sizeof(*ptd), GFP_KERNEL);
196 if (!ptd)
197 return -ENOMEM;
198
199 switch (pdev->device) {
200 case PCH_THERMAL_DID_WPT:
201 ptd->ops = &pch_dev_ops_wpt;
202 dev_name = "pch_wildcat_point";
203 break;
204 default:
205 dev_err(&pdev->dev, "unknown pch thermal device\n");
206 return -ENODEV;
207 }
208
209 pci_set_drvdata(pdev, ptd);
210 ptd->pdev = pdev;
211
212 err = pci_enable_device(pdev);
213 if (err) {
214 dev_err(&pdev->dev, "failed to enable pci device\n");
215 return err;
216 }
217
218 err = pci_request_regions(pdev, driver_name);
219 if (err) {
220 dev_err(&pdev->dev, "failed to request pci region\n");
221 goto error_disable;
222 }
223
224 ptd->hw_base = pci_ioremap_bar(pdev, 0);
225 if (!ptd->hw_base) {
226 err = -ENOMEM;
227 dev_err(&pdev->dev, "failed to map mem base\n");
228 goto error_release;
229 }
230
231 err = ptd->ops->hw_init(ptd, &nr_trips);
232 if (err)
233 goto error_cleanup;
234
235 ptd->tzd = thermal_zone_device_register(dev_name, nr_trips, 0, ptd,
236 &tzd_ops, NULL, 0, 0);
237 if (IS_ERR(ptd->tzd)) {
238 dev_err(&pdev->dev, "Failed to register thermal zone %s\n",
239 dev_name);
240 err = PTR_ERR(ptd->tzd);
241 goto error_cleanup;
242 }
243
244 return 0;
245
246 error_cleanup:
247 iounmap(ptd->hw_base);
248 error_release:
249 pci_release_regions(pdev);
250 error_disable:
251 pci_disable_device(pdev);
252 dev_err(&pdev->dev, "pci device failed to probe\n");
253 return err;
254 }
255
intel_pch_thermal_remove(struct pci_dev * pdev)256 static void intel_pch_thermal_remove(struct pci_dev *pdev)
257 {
258 struct pch_thermal_device *ptd = pci_get_drvdata(pdev);
259
260 thermal_zone_device_unregister(ptd->tzd);
261 iounmap(ptd->hw_base);
262 pci_set_drvdata(pdev, NULL);
263 pci_release_region(pdev, 0);
264 pci_disable_device(pdev);
265 }
266
267 static struct pci_device_id intel_pch_thermal_id[] = {
268 { PCI_DEVICE(PCI_VENDOR_ID_INTEL, PCH_THERMAL_DID_WPT) },
269 { 0, },
270 };
271 MODULE_DEVICE_TABLE(pci, intel_pch_thermal_id);
272
273 static struct pci_driver intel_pch_thermal_driver = {
274 .name = "intel_pch_thermal",
275 .id_table = intel_pch_thermal_id,
276 .probe = intel_pch_thermal_probe,
277 .remove = intel_pch_thermal_remove,
278 };
279
280 module_pci_driver(intel_pch_thermal_driver);
281
282 MODULE_LICENSE("GPL v2");
283 MODULE_DESCRIPTION("Intel PCH Thermal driver");
284