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(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 char *c, *l; 202 u32 *v; 203 204 ads = kmalloc(sizeof(struct smu_ad_sensor), GFP_KERNEL); 205 if (ads == NULL) 206 return NULL; 207 c = (char *)get_property(node, "device_type", NULL); 208 l = (char *)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 = (u32 *)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, &s); 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 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"); 483 484