drivers/macintosh/windfarm_smu_sensors.c

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