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1// SPDX-License-Identifier: GPL-2.0-only2/*3 * Windfarm PowerMac thermal control. SMU based sensors4 *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 DEBUG29 30#ifdef DEBUG31#define DBG(args...) printk(args)32#else33#define DBG(args...) do { } while(0)34#endif35 36/*37 * Various SMU "partitions" calibration objects for which we38 * keep pointers here for use by bits & pieces of the driver39 */40static struct smu_sdbp_cpuvcp *cpuvcp;41static int cpuvcp_version;42static struct smu_sdbp_cpudiode *cpudiode;43static struct smu_sdbp_slotspow *slotspow;44static u8 *debugswitches;45 46/*47 * SMU basic sensors objects48 */49 50static LIST_HEAD(smu_ads);51 52struct 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 59static 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 66static 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 88static 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 111static 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 132static 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 153static 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 175static const struct wf_sensor_ops smu_cputemp_ops = {176 .get_value = smu_cputemp_get,177 .release = smu_ads_release,178 .owner = THIS_MODULE,179};180static const struct wf_sensor_ops smu_cpuamp_ops = {181 .get_value = smu_cpuamp_get,182 .release = smu_ads_release,183 .owner = THIS_MODULE,184};185static const struct wf_sensor_ops smu_cpuvolt_ops = {186 .get_value = smu_cpuvolt_get,187 .release = smu_ads_release,188 .owner = THIS_MODULE,189};190static 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 197static 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 location211 * properties, while Darwin uses the sensor-id's.212 * The problem with the IDs is that they are model specific while it213 * looks like apple has been doing a reasonably good job at keeping214 * the names and locations consistents so I'll stick with the names215 * 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 } else254 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 object271 */272 273struct smu_cpu_power_sensor {274 struct list_head link;275 struct wf_sensor *volts;276 struct wf_sensor *amps;277 unsigned int fake_volts : 1;278 unsigned 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 283static struct smu_cpu_power_sensor *smu_cpu_power;284 285static 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 296static 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, &s);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 329static 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 336static struct smu_cpu_power_sensor *337smu_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 } else358 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 to362 * 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 } else371 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 381static 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 409static 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 457static 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 474module_init(smu_sensors_init);475module_exit(smu_sensors_exit);476 477MODULE_AUTHOR("Benjamin Herrenschmidt <benh@kernel.crashing.org>");478MODULE_DESCRIPTION("SMU sensor objects for PowerMacs thermal control");479MODULE_LICENSE("GPL");480 481