drivers/macintosh/windfarm_smu_sensors.c

   1 // SPDX-License-Identifier: GPL-2.0-only
   2 /*
   3  * Windfarm PowerMac thermal control. SMU based sensors
   4  *
   5  * (c) Copyright 2005 Benjamin Herrenschmidt, IBM Corp.
   6  *                    <benh@kernel.crashing.org>
   7  */
   8
   9 #include <linux/types.h>
  10 #include <linux/errno.h>
  11 #include <linux/kernel.h>
  12 #include <linux/delay.h>
  13 #include <linux/slab.h>
  14 #include <linux/init.h>
  15 #include <linux/wait.h>
  16 #include <linux/completion.h>
  17 #include <linux/of.h>
  18
  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 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
 197 static struct smu_ad_sensor *smu_ads_create(struct device_node *node)
 198 {
 199         struct smu_ad_sensor *ads;
 200         const char *l;
 201         const u32 *v;
 202
 203         ads = kmalloc(sizeof(struct smu_ad_sensor), GFP_KERNEL);
 204         if (ads == NULL)
 205                 return NULL;
 206         l = of_get_property(node, "location", NULL);
 207         if (l == NULL)
 208                 goto fail;
 209
 210         /* We currently pick the sensors based on the OF name and location
 211          * properties, while Darwin uses the sensor-id's.
 212          * The problem with the IDs is that they are model specific while it
 213          * looks like apple has been doing a reasonably good job at keeping
 214          * the names and locations consistents so I'll stick with the names
 215          * and locations for now.
 216          */
 217         if (of_node_is_type(node, "temp-sensor") &&
 218             !strcmp(l, "CPU T-Diode")) {
 219                 ads->sens.ops = &smu_cputemp_ops;
 220                 ads->sens.name = "cpu-temp";
 221                 if (cpudiode == NULL) {
 222                         DBG("wf: cpudiode partition (%02x) not found\n",
 223                             SMU_SDB_CPUDIODE_ID);
 224                         goto fail;
 225                 }
 226         } else if (of_node_is_type(node, "current-sensor") &&
 227                    !strcmp(l, "CPU Current")) {
 228                 ads->sens.ops = &smu_cpuamp_ops;
 229                 ads->sens.name = "cpu-current";
 230                 if (cpuvcp == NULL) {
 231                         DBG("wf: cpuvcp partition (%02x) not found\n",
 232                             SMU_SDB_CPUVCP_ID);
 233                         goto fail;
 234                 }
 235         } else if (of_node_is_type(node, "voltage-sensor") &&
 236                    !strcmp(l, "CPU Voltage")) {
 237                 ads->sens.ops = &smu_cpuvolt_ops;
 238                 ads->sens.name = "cpu-voltage";
 239                 if (cpuvcp == NULL) {
 240                         DBG("wf: cpuvcp partition (%02x) not found\n",
 241                             SMU_SDB_CPUVCP_ID);
 242                         goto fail;
 243                 }
 244         } else if (of_node_is_type(node, "power-sensor") &&
 245                    !strcmp(l, "Slots Power")) {
 246                 ads->sens.ops = &smu_slotspow_ops;
 247                 ads->sens.name = "slots-power";
 248                 if (slotspow == NULL) {
 249                         DBG("wf: slotspow partition (%02x) not found\n",
 250                             SMU_SDB_SLOTSPOW_ID);
 251                         goto fail;
 252                 }
 253         } else
 254                 goto fail;
 255
 256         v = of_get_property(node, "reg", NULL);
 257         if (v == NULL)
 258                 goto fail;
 259         ads->reg = *v;
 260
 261         if (wf_register_sensor(&ads->sens))
 262                 goto fail;
 263         return ads;
 264  fail:
 265         kfree(ads);
 266         return NULL;
 267 }
 268
 269 /*
 270  * SMU Power combo sensor object
 271  */
 272
 273 struct smu_cpu_power_sensor {
 274         struct list_head        link;
 275         struct wf_sensor        *volts;
 276         struct wf_sensor        *amps;
 277         int                     fake_volts : 1;
 278         int                     quadratic : 1;
 279         struct wf_sensor        sens;
 280 };
 281 #define to_smu_cpu_power(c) container_of(c, struct smu_cpu_power_sensor, sens)
 282
 283 static struct smu_cpu_power_sensor *smu_cpu_power;
 284
 285 static void smu_cpu_power_release(struct wf_sensor *sr)
 286 {
 287         struct smu_cpu_power_sensor *pow = to_smu_cpu_power(sr);
 288
 289         if (pow->volts)
 290                 wf_put_sensor(pow->volts);
 291         if (pow->amps)
 292                 wf_put_sensor(pow->amps);
 293         kfree(pow);
 294 }
 295
 296 static int smu_cpu_power_get(struct wf_sensor *sr, s32 *value)
 297 {
 298         struct smu_cpu_power_sensor *pow = to_smu_cpu_power(sr);
 299         s32 volts, amps, power;
 300         u64 tmps, tmpa, tmpb;
 301         int rc;
 302
 303         rc = pow->amps->ops->get_value(pow->amps, &amps);
 304         if (rc)
 305                 return rc;
 306
 307         if (pow->fake_volts) {
 308                 *value = amps * 12 - 0x30000;
 309                 return 0;
 310         }
 311
 312         rc = pow->volts->ops->get_value(pow->volts, &volts);
 313         if (rc)
 314                 return rc;
 315
 316         power = (s32)((((u64)volts) * ((u64)amps)) >> 16);
 317         if (!pow->quadratic) {
 318                 *value = power;
 319                 return 0;
 320         }
 321         tmps = (((u64)power) * ((u64)power)) >> 16;
 322         tmpa = ((u64)cpuvcp->power_quads[0]) * tmps;
 323         tmpb = ((u64)cpuvcp->power_quads[1]) * ((u64)power);
 324         *value = (tmpa >> 28) + (tmpb >> 28) + (cpuvcp->power_quads[2] >> 12);
 325
 326         return 0;
 327 }
 328
 329 static const struct wf_sensor_ops smu_cpu_power_ops = {
 330         .get_value      = smu_cpu_power_get,
 331         .release        = smu_cpu_power_release,
 332         .owner          = THIS_MODULE,
 333 };
 334
 335
 336 static struct smu_cpu_power_sensor *
 337 smu_cpu_power_create(struct wf_sensor *volts, struct wf_sensor *amps)
 338 {
 339         struct smu_cpu_power_sensor *pow;
 340
 341         pow = kmalloc(sizeof(struct smu_cpu_power_sensor), GFP_KERNEL);
 342         if (pow == NULL)
 343                 return NULL;
 344         pow->sens.ops = &smu_cpu_power_ops;
 345         pow->sens.name = "cpu-power";
 346
 347         wf_get_sensor(volts);
 348         pow->volts = volts;
 349         wf_get_sensor(amps);
 350         pow->amps = amps;
 351
 352         /* Some early machines need a faked voltage */
 353         if (debugswitches && ((*debugswitches) & 0x80)) {
 354                 printk(KERN_INFO "windfarm: CPU Power sensor using faked"
 355                        " voltage !\n");
 356                 pow->fake_volts = 1;
 357         } else
 358                 pow->fake_volts = 0;
 359
 360         /* Try to use quadratic transforms on PowerMac8,1 and 9,1 for now,
 361          * I yet have to figure out what's up with 8,2 and will have to
 362          * adjust for later, unless we can 100% trust the SDB partition...
 363          */
 364         if ((of_machine_is_compatible("PowerMac8,1") ||
 365              of_machine_is_compatible("PowerMac8,2") ||
 366              of_machine_is_compatible("PowerMac9,1")) &&
 367             cpuvcp_version >= 2) {
 368                 pow->quadratic = 1;
 369                 DBG("windfarm: CPU Power using quadratic transform\n");
 370         } else
 371                 pow->quadratic = 0;
 372
 373         if (wf_register_sensor(&pow->sens))
 374                 goto fail;
 375         return pow;
 376  fail:
 377         kfree(pow);
 378         return NULL;
 379 }
 380
 381 static void smu_fetch_param_partitions(void)
 382 {
 383         const struct smu_sdbp_header *hdr;
 384
 385         /* Get CPU voltage/current/power calibration data */
 386         hdr = smu_get_sdb_partition(SMU_SDB_CPUVCP_ID, NULL);
 387         if (hdr != NULL) {
 388                 cpuvcp = (struct smu_sdbp_cpuvcp *)&hdr[1];
 389                 /* Keep version around */
 390                 cpuvcp_version = hdr->version;
 391         }
 392
 393         /* Get CPU diode calibration data */
 394         hdr = smu_get_sdb_partition(SMU_SDB_CPUDIODE_ID, NULL);
 395         if (hdr != NULL)
 396                 cpudiode = (struct smu_sdbp_cpudiode *)&hdr[1];
 397
 398         /* Get slots power calibration data if any */
 399         hdr = smu_get_sdb_partition(SMU_SDB_SLOTSPOW_ID, NULL);
 400         if (hdr != NULL)
 401                 slotspow = (struct smu_sdbp_slotspow *)&hdr[1];
 402
 403         /* Get debug switches if any */
 404         hdr = smu_get_sdb_partition(SMU_SDB_DEBUG_SWITCHES_ID, NULL);
 405         if (hdr != NULL)
 406                 debugswitches = (u8 *)&hdr[1];
 407 }
 408
 409 static int __init smu_sensors_init(void)
 410 {
 411         struct device_node *smu, *sensors, *s;
 412         struct smu_ad_sensor *volt_sensor = NULL, *curr_sensor = NULL;
 413
 414         if (!smu_present())
 415                 return -ENODEV;
 416
 417         /* Get parameters partitions */
 418         smu_fetch_param_partitions();
 419
 420         smu = of_find_node_by_type(NULL, "smu");
 421         if (smu == NULL)
 422                 return -ENODEV;
 423
 424         /* Look for sensors subdir */
 425         for_each_child_of_node(smu, sensors)
 426                 if (of_node_name_eq(sensors, "sensors"))
 427                         break;
 428
 429         of_node_put(smu);
 430
 431         /* Create basic sensors */
 432         for (s = NULL;
 433              sensors && (s = of_get_next_child(sensors, s)) != NULL;) {
 434                 struct smu_ad_sensor *ads;
 435
 436                 ads = smu_ads_create(s);
 437                 if (ads == NULL)
 438                         continue;
 439                 list_add(&ads->link, &smu_ads);
 440                 /* keep track of cpu voltage & current */
 441                 if (!strcmp(ads->sens.name, "cpu-voltage"))
 442                         volt_sensor = ads;
 443                 else if (!strcmp(ads->sens.name, "cpu-current"))
 444                         curr_sensor = ads;
 445         }
 446
 447         of_node_put(sensors);
 448
 449         /* Create CPU power sensor if possible */
 450         if (volt_sensor && curr_sensor)
 451                 smu_cpu_power = smu_cpu_power_create(&volt_sensor->sens,
 452                                                      &curr_sensor->sens);
 453
 454         return 0;
 455 }
 456
 457 static void __exit smu_sensors_exit(void)
 458 {
 459         struct smu_ad_sensor *ads;
 460
 461         /* dispose of power sensor */
 462         if (smu_cpu_power)
 463                 wf_unregister_sensor(&smu_cpu_power->sens);
 464
 465         /* dispose of basic sensors */
 466         while (!list_empty(&smu_ads)) {
 467                 ads = list_entry(smu_ads.next, struct smu_ad_sensor, link);
 468                 list_del(&ads->link);
 469                 wf_unregister_sensor(&ads->sens);
 470         }
 471 }
 472
 473
 474 module_init(smu_sensors_init);
 475 module_exit(smu_sensors_exit);
 476
 477 MODULE_AUTHOR("Benjamin Herrenschmidt <benh@kernel.crashing.org>");
 478 MODULE_DESCRIPTION("SMU sensor objects for PowerMacs thermal control");
 479 MODULE_LICENSE("GPL");
 480