1 /*
2 * Windfarm PowerMac thermal control. SMU based sensors
3 *
4 * (c) Copyright 2005 Benjamin Herrenschmidt, IBM Corp.
5 * <benh@kernel.crashing.org>
6 *
7 * Released under the term of the GNU GPL v2.
8 */
9
10 #include <linux/types.h>
11 #include <linux/errno.h>
12 #include <linux/kernel.h>
13 #include <linux/delay.h>
14 #include <linux/slab.h>
15 #include <linux/init.h>
16 #include <linux/wait.h>
17 #include <linux/completion.h>
18 #include <asm/prom.h>
19 #include <asm/machdep.h>
20 #include <asm/io.h>
21 #include <asm/sections.h>
22 #include <asm/smu.h>
23
24 #include "windfarm.h"
25
26 #define VERSION "0.2"
27
28 #undef DEBUG
29
30 #ifdef DEBUG
31 #define DBG(args...) printk(args)
32 #else
33 #define DBG(args...) do { } while(0)
34 #endif
35
36 /*
37 * Various SMU "partitions" calibration objects for which we
38 * keep pointers here for use by bits & pieces of the driver
39 */
40 static struct smu_sdbp_cpuvcp *cpuvcp;
41 static int cpuvcp_version;
42 static struct smu_sdbp_cpudiode *cpudiode;
43 static struct smu_sdbp_slotspow *slotspow;
44 static u8 *debugswitches;
45
46 /*
47 * SMU basic sensors objects
48 */
49
50 static LIST_HEAD(smu_ads);
51
52 struct smu_ad_sensor {
53 struct list_head link;
54 u32 reg; /* index in SMU */
55 struct wf_sensor sens;
56 };
57 #define to_smu_ads(c) container_of(c, struct smu_ad_sensor, sens)
58
smu_ads_release(struct wf_sensor * sr)59 static void smu_ads_release(struct wf_sensor *sr)
60 {
61 struct smu_ad_sensor *ads = to_smu_ads(sr);
62
63 kfree(ads);
64 }
65
smu_read_adc(u8 id,s32 * value)66 static int smu_read_adc(u8 id, s32 *value)
67 {
68 struct smu_simple_cmd cmd;
69 DECLARE_COMPLETION_ONSTACK(comp);
70 int rc;
71
72 rc = smu_queue_simple(&cmd, SMU_CMD_READ_ADC, 1,
73 smu_done_complete, &comp, id);
74 if (rc)
75 return rc;
76 wait_for_completion(&comp);
77 if (cmd.cmd.status != 0)
78 return cmd.cmd.status;
79 if (cmd.cmd.reply_len != 2) {
80 printk(KERN_ERR "winfarm: read ADC 0x%x returned %d bytes !\n",
81 id, cmd.cmd.reply_len);
82 return -EIO;
83 }
84 *value = *((u16 *)cmd.buffer);
85 return 0;
86 }
87
smu_cputemp_get(struct wf_sensor * sr,s32 * value)88 static int smu_cputemp_get(struct wf_sensor *sr, s32 *value)
89 {
90 struct smu_ad_sensor *ads = to_smu_ads(sr);
91 int rc;
92 s32 val;
93 s64 scaled;
94
95 rc = smu_read_adc(ads->reg, &val);
96 if (rc) {
97 printk(KERN_ERR "windfarm: read CPU temp failed, err %d\n",
98 rc);
99 return rc;
100 }
101
102 /* Ok, we have to scale & adjust, taking units into account */
103 scaled = (s64)(((u64)val) * (u64)cpudiode->m_value);
104 scaled >>= 3;
105 scaled += ((s64)cpudiode->b_value) << 9;
106 *value = (s32)(scaled << 1);
107
108 return 0;
109 }
110
smu_cpuamp_get(struct wf_sensor * sr,s32 * value)111 static int smu_cpuamp_get(struct wf_sensor *sr, s32 *value)
112 {
113 struct smu_ad_sensor *ads = to_smu_ads(sr);
114 s32 val, scaled;
115 int rc;
116
117 rc = smu_read_adc(ads->reg, &val);
118 if (rc) {
119 printk(KERN_ERR "windfarm: read CPU current failed, err %d\n",
120 rc);
121 return rc;
122 }
123
124 /* Ok, we have to scale & adjust, taking units into account */
125 scaled = (s32)(val * (u32)cpuvcp->curr_scale);
126 scaled += (s32)cpuvcp->curr_offset;
127 *value = scaled << 4;
128
129 return 0;
130 }
131
smu_cpuvolt_get(struct wf_sensor * sr,s32 * value)132 static int smu_cpuvolt_get(struct wf_sensor *sr, s32 *value)
133 {
134 struct smu_ad_sensor *ads = to_smu_ads(sr);
135 s32 val, scaled;
136 int rc;
137
138 rc = smu_read_adc(ads->reg, &val);
139 if (rc) {
140 printk(KERN_ERR "windfarm: read CPU voltage failed, err %d\n",
141 rc);
142 return rc;
143 }
144
145 /* Ok, we have to scale & adjust, taking units into account */
146 scaled = (s32)(val * (u32)cpuvcp->volt_scale);
147 scaled += (s32)cpuvcp->volt_offset;
148 *value = scaled << 4;
149
150 return 0;
151 }
152
smu_slotspow_get(struct wf_sensor * sr,s32 * value)153 static int smu_slotspow_get(struct wf_sensor *sr, s32 *value)
154 {
155 struct smu_ad_sensor *ads = to_smu_ads(sr);
156 s32 val, scaled;
157 int rc;
158
159 rc = smu_read_adc(ads->reg, &val);
160 if (rc) {
161 printk(KERN_ERR "windfarm: read slots power failed, err %d\n",
162 rc);
163 return rc;
164 }
165
166 /* Ok, we have to scale & adjust, taking units into account */
167 scaled = (s32)(val * (u32)slotspow->pow_scale);
168 scaled += (s32)slotspow->pow_offset;
169 *value = scaled << 4;
170
171 return 0;
172 }
173
174
175 static const struct wf_sensor_ops smu_cputemp_ops = {
176 .get_value = smu_cputemp_get,
177 .release = smu_ads_release,
178 .owner = THIS_MODULE,
179 };
180 static const struct wf_sensor_ops smu_cpuamp_ops = {
181 .get_value = smu_cpuamp_get,
182 .release = smu_ads_release,
183 .owner = THIS_MODULE,
184 };
185 static const struct wf_sensor_ops smu_cpuvolt_ops = {
186 .get_value = smu_cpuvolt_get,
187 .release = smu_ads_release,
188 .owner = THIS_MODULE,
189 };
190 static const struct wf_sensor_ops smu_slotspow_ops = {
191 .get_value = smu_slotspow_get,
192 .release = smu_ads_release,
193 .owner = THIS_MODULE,
194 };
195
196
smu_ads_create(struct device_node * node)197 static struct smu_ad_sensor *smu_ads_create(struct device_node *node)
198 {
199 struct smu_ad_sensor *ads;
200 const char *c, *l;
201 const u32 *v;
202
203 ads = kmalloc(sizeof(struct smu_ad_sensor), GFP_KERNEL);
204 if (ads == NULL)
205 return NULL;
206 c = of_get_property(node, "device_type", NULL);
207 l = of_get_property(node, "location", NULL);
208 if (c == NULL || l == NULL)
209 goto fail;
210
211 /* We currently pick the sensors based on the OF name and location
212 * properties, while Darwin uses the sensor-id's.
213 * The problem with the IDs is that they are model specific while it
214 * looks like apple has been doing a reasonably good job at keeping
215 * the names and locations consistents so I'll stick with the names
216 * and locations for now.
217 */
218 if (!strcmp(c, "temp-sensor") &&
219 !strcmp(l, "CPU T-Diode")) {
220 ads->sens.ops = &smu_cputemp_ops;
221 ads->sens.name = "cpu-temp";
222 if (cpudiode == NULL) {
223 DBG("wf: cpudiode partition (%02x) not found\n",
224 SMU_SDB_CPUDIODE_ID);
225 goto fail;
226 }
227 } else if (!strcmp(c, "current-sensor") &&
228 !strcmp(l, "CPU Current")) {
229 ads->sens.ops = &smu_cpuamp_ops;
230 ads->sens.name = "cpu-current";
231 if (cpuvcp == NULL) {
232 DBG("wf: cpuvcp partition (%02x) not found\n",
233 SMU_SDB_CPUVCP_ID);
234 goto fail;
235 }
236 } else if (!strcmp(c, "voltage-sensor") &&
237 !strcmp(l, "CPU Voltage")) {
238 ads->sens.ops = &smu_cpuvolt_ops;
239 ads->sens.name = "cpu-voltage";
240 if (cpuvcp == NULL) {
241 DBG("wf: cpuvcp partition (%02x) not found\n",
242 SMU_SDB_CPUVCP_ID);
243 goto fail;
244 }
245 } else if (!strcmp(c, "power-sensor") &&
246 !strcmp(l, "Slots Power")) {
247 ads->sens.ops = &smu_slotspow_ops;
248 ads->sens.name = "slots-power";
249 if (slotspow == NULL) {
250 DBG("wf: slotspow partition (%02x) not found\n",
251 SMU_SDB_SLOTSPOW_ID);
252 goto fail;
253 }
254 } else
255 goto fail;
256
257 v = of_get_property(node, "reg", NULL);
258 if (v == NULL)
259 goto fail;
260 ads->reg = *v;
261
262 if (wf_register_sensor(&ads->sens))
263 goto fail;
264 return ads;
265 fail:
266 kfree(ads);
267 return NULL;
268 }
269
270 /*
271 * SMU Power combo sensor object
272 */
273
274 struct smu_cpu_power_sensor {
275 struct list_head link;
276 struct wf_sensor *volts;
277 struct wf_sensor *amps;
278 int fake_volts : 1;
279 int quadratic : 1;
280 struct wf_sensor sens;
281 };
282 #define to_smu_cpu_power(c) container_of(c, struct smu_cpu_power_sensor, sens)
283
284 static struct smu_cpu_power_sensor *smu_cpu_power;
285
smu_cpu_power_release(struct wf_sensor * sr)286 static void smu_cpu_power_release(struct wf_sensor *sr)
287 {
288 struct smu_cpu_power_sensor *pow = to_smu_cpu_power(sr);
289
290 if (pow->volts)
291 wf_put_sensor(pow->volts);
292 if (pow->amps)
293 wf_put_sensor(pow->amps);
294 kfree(pow);
295 }
296
smu_cpu_power_get(struct wf_sensor * sr,s32 * value)297 static int smu_cpu_power_get(struct wf_sensor *sr, s32 *value)
298 {
299 struct smu_cpu_power_sensor *pow = to_smu_cpu_power(sr);
300 s32 volts, amps, power;
301 u64 tmps, tmpa, tmpb;
302 int rc;
303
304 rc = pow->amps->ops->get_value(pow->amps, &s);
305 if (rc)
306 return rc;
307
308 if (pow->fake_volts) {
309 *value = amps * 12 - 0x30000;
310 return 0;
311 }
312
313 rc = pow->volts->ops->get_value(pow->volts, &volts);
314 if (rc)
315 return rc;
316
317 power = (s32)((((u64)volts) * ((u64)amps)) >> 16);
318 if (!pow->quadratic) {
319 *value = power;
320 return 0;
321 }
322 tmps = (((u64)power) * ((u64)power)) >> 16;
323 tmpa = ((u64)cpuvcp->power_quads[0]) * tmps;
324 tmpb = ((u64)cpuvcp->power_quads[1]) * ((u64)power);
325 *value = (tmpa >> 28) + (tmpb >> 28) + (cpuvcp->power_quads[2] >> 12);
326
327 return 0;
328 }
329
330 static const struct wf_sensor_ops smu_cpu_power_ops = {
331 .get_value = smu_cpu_power_get,
332 .release = smu_cpu_power_release,
333 .owner = THIS_MODULE,
334 };
335
336
337 static struct smu_cpu_power_sensor *
smu_cpu_power_create(struct wf_sensor * volts,struct wf_sensor * amps)338 smu_cpu_power_create(struct wf_sensor *volts, struct wf_sensor *amps)
339 {
340 struct smu_cpu_power_sensor *pow;
341
342 pow = kmalloc(sizeof(struct smu_cpu_power_sensor), GFP_KERNEL);
343 if (pow == NULL)
344 return NULL;
345 pow->sens.ops = &smu_cpu_power_ops;
346 pow->sens.name = "cpu-power";
347
348 wf_get_sensor(volts);
349 pow->volts = volts;
350 wf_get_sensor(amps);
351 pow->amps = amps;
352
353 /* Some early machines need a faked voltage */
354 if (debugswitches && ((*debugswitches) & 0x80)) {
355 printk(KERN_INFO "windfarm: CPU Power sensor using faked"
356 " voltage !\n");
357 pow->fake_volts = 1;
358 } else
359 pow->fake_volts = 0;
360
361 /* Try to use quadratic transforms on PowerMac8,1 and 9,1 for now,
362 * I yet have to figure out what's up with 8,2 and will have to
363 * adjust for later, unless we can 100% trust the SDB partition...
364 */
365 if ((of_machine_is_compatible("PowerMac8,1") ||
366 of_machine_is_compatible("PowerMac8,2") ||
367 of_machine_is_compatible("PowerMac9,1")) &&
368 cpuvcp_version >= 2) {
369 pow->quadratic = 1;
370 DBG("windfarm: CPU Power using quadratic transform\n");
371 } else
372 pow->quadratic = 0;
373
374 if (wf_register_sensor(&pow->sens))
375 goto fail;
376 return pow;
377 fail:
378 kfree(pow);
379 return NULL;
380 }
381
smu_fetch_param_partitions(void)382 static void smu_fetch_param_partitions(void)
383 {
384 const struct smu_sdbp_header *hdr;
385
386 /* Get CPU voltage/current/power calibration data */
387 hdr = smu_get_sdb_partition(SMU_SDB_CPUVCP_ID, NULL);
388 if (hdr != NULL) {
389 cpuvcp = (struct smu_sdbp_cpuvcp *)&hdr[1];
390 /* Keep version around */
391 cpuvcp_version = hdr->version;
392 }
393
394 /* Get CPU diode calibration data */
395 hdr = smu_get_sdb_partition(SMU_SDB_CPUDIODE_ID, NULL);
396 if (hdr != NULL)
397 cpudiode = (struct smu_sdbp_cpudiode *)&hdr[1];
398
399 /* Get slots power calibration data if any */
400 hdr = smu_get_sdb_partition(SMU_SDB_SLOTSPOW_ID, NULL);
401 if (hdr != NULL)
402 slotspow = (struct smu_sdbp_slotspow *)&hdr[1];
403
404 /* Get debug switches if any */
405 hdr = smu_get_sdb_partition(SMU_SDB_DEBUG_SWITCHES_ID, NULL);
406 if (hdr != NULL)
407 debugswitches = (u8 *)&hdr[1];
408 }
409
smu_sensors_init(void)410 static int __init smu_sensors_init(void)
411 {
412 struct device_node *smu, *sensors, *s;
413 struct smu_ad_sensor *volt_sensor = NULL, *curr_sensor = NULL;
414
415 if (!smu_present())
416 return -ENODEV;
417
418 /* Get parameters partitions */
419 smu_fetch_param_partitions();
420
421 smu = of_find_node_by_type(NULL, "smu");
422 if (smu == NULL)
423 return -ENODEV;
424
425 /* Look for sensors subdir */
426 for (sensors = NULL;
427 (sensors = of_get_next_child(smu, sensors)) != NULL;)
428 if (!strcmp(sensors->name, "sensors"))
429 break;
430
431 of_node_put(smu);
432
433 /* Create basic sensors */
434 for (s = NULL;
435 sensors && (s = of_get_next_child(sensors, s)) != NULL;) {
436 struct smu_ad_sensor *ads;
437
438 ads = smu_ads_create(s);
439 if (ads == NULL)
440 continue;
441 list_add(&ads->link, &smu_ads);
442 /* keep track of cpu voltage & current */
443 if (!strcmp(ads->sens.name, "cpu-voltage"))
444 volt_sensor = ads;
445 else if (!strcmp(ads->sens.name, "cpu-current"))
446 curr_sensor = ads;
447 }
448
449 of_node_put(sensors);
450
451 /* Create CPU power sensor if possible */
452 if (volt_sensor && curr_sensor)
453 smu_cpu_power = smu_cpu_power_create(&volt_sensor->sens,
454 &curr_sensor->sens);
455
456 return 0;
457 }
458
smu_sensors_exit(void)459 static void __exit smu_sensors_exit(void)
460 {
461 struct smu_ad_sensor *ads;
462
463 /* dispose of power sensor */
464 if (smu_cpu_power)
465 wf_unregister_sensor(&smu_cpu_power->sens);
466
467 /* dispose of basic sensors */
468 while (!list_empty(&smu_ads)) {
469 ads = list_entry(smu_ads.next, struct smu_ad_sensor, link);
470 list_del(&ads->link);
471 wf_unregister_sensor(&ads->sens);
472 }
473 }
474
475
476 module_init(smu_sensors_init);
477 module_exit(smu_sensors_exit);
478
479 MODULE_AUTHOR("Benjamin Herrenschmidt <benh@kernel.crashing.org>");
480 MODULE_DESCRIPTION("SMU sensor objects for PowerMacs thermal control");
481 MODULE_LICENSE("GPL");
482
483
