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/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
  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
  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
  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
 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
 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
 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 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 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 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 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
 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
 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
 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, &amps);
 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 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 *
 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
 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
 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
 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