1/* 2 * Windfarm PowerMac thermal control. SMU "satellite" controller sensors. 3 * 4 * Copyright (C) 2005 Paul Mackerras, IBM Corp. <paulus@samba.org> 5 * 6 * Released under the terms of the GNU GPL v2. 7 */ 8 9#include <linux/types.h> 10#include <linux/errno.h> 11#include <linux/kernel.h> 12#include <linux/slab.h> 13#include <linux/init.h> 14#include <linux/wait.h> 15#include <linux/i2c.h> 16#include <asm/semaphore.h> 17#include <asm/prom.h> 18#include <asm/smu.h> 19#include <asm/pmac_low_i2c.h> 20 21#include "windfarm.h" 22 23#define VERSION "0.2" 24 25#define DEBUG 26 27#ifdef DEBUG 28#define DBG(args...) printk(args) 29#else 30#define DBG(args...) do { } while(0) 31#endif 32 33/* If the cache is older than 800ms we'll refetch it */ 34#define MAX_AGE msecs_to_jiffies(800) 35 36struct wf_sat { 37 int nr; 38 atomic_t refcnt; 39 struct semaphore mutex; 40 unsigned long last_read; /* jiffies when cache last updated */ 41 u8 cache[16]; 42 struct i2c_client i2c; 43 struct device_node *node; 44}; 45 46static struct wf_sat *sats[2]; 47 48struct wf_sat_sensor { 49 int index; 50 int index2; /* used for power sensors */ 51 int shift; 52 struct wf_sat *sat; 53 struct wf_sensor sens; 54}; 55 56#define wf_to_sat(c) container_of(c, struct wf_sat_sensor, sens) 57#define i2c_to_sat(c) container_of(c, struct wf_sat, i2c) 58 59static int wf_sat_attach(struct i2c_adapter *adapter); 60static int wf_sat_detach(struct i2c_client *client); 61 62static struct i2c_driver wf_sat_driver = { 63 .driver = { 64 .name = "wf_smu_sat", 65 }, 66 .attach_adapter = wf_sat_attach, 67 .detach_client = wf_sat_detach, 68}; 69 70static int sat_read_block(struct i2c_client *client, u8 command, 71 u8 *values, int len) 72{ 73 union i2c_smbus_data data; 74 int err; 75 76 data.block[0] = len; 77 err = i2c_smbus_xfer(client->adapter, client->addr, client->flags, 78 I2C_SMBUS_READ, command, I2C_SMBUS_I2C_BLOCK_DATA, 79 &data); 80 if (!err) 81 memcpy(values, data.block, len); 82 return err; 83} 84 85struct smu_sdbp_header *smu_sat_get_sdb_partition(unsigned int sat_id, int id, 86 unsigned int *size) 87{ 88 struct wf_sat *sat; 89 int err; 90 unsigned int i, len; 91 u8 *buf; 92 u8 data[4]; 93 94 /* TODO: Add the resulting partition to the device-tree */ 95 96 if (sat_id > 1 || (sat = sats[sat_id]) == NULL) 97 return NULL; 98 99 err = i2c_smbus_write_word_data(&sat->i2c, 8, id << 8); 100 if (err) { 101 printk(KERN_ERR "smu_sat_get_sdb_part wr error %d\n", err); 102 return NULL; 103 } 104 105 len = i2c_smbus_read_word_data(&sat->i2c, 9); 106 if (len < 0) { 107 printk(KERN_ERR "smu_sat_get_sdb_part rd len error\n"); 108 return NULL; 109 } 110 if (len == 0) { 111 printk(KERN_ERR "smu_sat_get_sdb_part no partition %x\n", id); 112 return NULL; 113 } 114 115 len = le16_to_cpu(len); 116 len = (len + 3) & ~3; 117 buf = kmalloc(len, GFP_KERNEL); 118 if (buf == NULL) 119 return NULL; 120 121 for (i = 0; i < len; i += 4) { 122 err = sat_read_block(&sat->i2c, 0xa, data, 4); 123 if (err) { 124 printk(KERN_ERR "smu_sat_get_sdb_part rd err %d\n", 125 err); 126 goto fail; 127 } 128 buf[i] = data[1]; 129 buf[i+1] = data[0]; 130 buf[i+2] = data[3]; 131 buf[i+3] = data[2]; 132 } 133#ifdef DEBUG 134 DBG(KERN_DEBUG "sat %d partition %x:", sat_id, id); 135 for (i = 0; i < len; ++i) 136 DBG(" %x", buf[i]); 137 DBG("\n"); 138#endif 139 140 if (size) 141 *size = len; 142 return (struct smu_sdbp_header *) buf; 143 144 fail: 145 kfree(buf); 146 return NULL; 147} 148EXPORT_SYMBOL_GPL(smu_sat_get_sdb_partition); 149 150/* refresh the cache */ 151static int wf_sat_read_cache(struct wf_sat *sat) 152{ 153 int err; 154 155 err = sat_read_block(&sat->i2c, 0x3f, sat->cache, 16); 156 if (err) 157 return err; 158 sat->last_read = jiffies; 159#ifdef LOTSA_DEBUG 160 { 161 int i; 162 DBG(KERN_DEBUG "wf_sat_get: data is"); 163 for (i = 0; i < 16; ++i) 164 DBG(" %.2x", sat->cache[i]); 165 DBG("\n"); 166 } 167#endif 168 return 0; 169} 170 171static int wf_sat_get(struct wf_sensor *sr, s32 *value) 172{ 173 struct wf_sat_sensor *sens = wf_to_sat(sr); 174 struct wf_sat *sat = sens->sat; 175 int i, err; 176 s32 val; 177 178 if (sat->i2c.adapter == NULL) 179 return -ENODEV; 180 181 down(&sat->mutex); 182 if (time_after(jiffies, (sat->last_read + MAX_AGE))) { 183 err = wf_sat_read_cache(sat); 184 if (err) 185 goto fail; 186 } 187 188 i = sens->index * 2; 189 val = ((sat->cache[i] << 8) + sat->cache[i+1]) << sens->shift; 190 if (sens->index2 >= 0) { 191 i = sens->index2 * 2; 192 /* 4.12 * 8.8 -> 12.20; shift right 4 to get 16.16 */ 193 val = (val * ((sat->cache[i] << 8) + sat->cache[i+1])) >> 4; 194 } 195 196 *value = val; 197 err = 0; 198 199 fail: 200 up(&sat->mutex); 201 return err; 202} 203 204static void wf_sat_release(struct wf_sensor *sr) 205{ 206 struct wf_sat_sensor *sens = wf_to_sat(sr); 207 struct wf_sat *sat = sens->sat; 208 209 if (atomic_dec_and_test(&sat->refcnt)) { 210 if (sat->i2c.adapter) { 211 i2c_detach_client(&sat->i2c); 212 sat->i2c.adapter = NULL; 213 } 214 if (sat->nr >= 0) 215 sats[sat->nr] = NULL; 216 kfree(sat); 217 } 218 kfree(sens); 219} 220 221static struct wf_sensor_ops wf_sat_ops = { 222 .get_value = wf_sat_get, 223 .release = wf_sat_release, 224 .owner = THIS_MODULE, 225}; 226 227static void wf_sat_create(struct i2c_adapter *adapter, struct device_node *dev) 228{ 229 struct wf_sat *sat; 230 struct wf_sat_sensor *sens; 231 const u32 *reg; 232 const char *loc, *type; 233 u8 addr, chip, core; 234 struct device_node *child; 235 int shift, cpu, index; 236 char *name; 237 int vsens[2], isens[2]; 238 239 reg = of_get_property(dev, "reg", NULL); 240 if (reg == NULL) 241 return; 242 addr = *reg; 243 DBG(KERN_DEBUG "wf_sat: creating sat at address %x\n", addr); 244 245 sat = kzalloc(sizeof(struct wf_sat), GFP_KERNEL); 246 if (sat == NULL) 247 return; 248 sat->nr = -1; 249 sat->node = of_node_get(dev); 250 atomic_set(&sat->refcnt, 0); 251 init_MUTEX(&sat->mutex); 252 sat->i2c.addr = (addr >> 1) & 0x7f; 253 sat->i2c.adapter = adapter; 254 sat->i2c.driver = &wf_sat_driver; 255 strncpy(sat->i2c.name, "smu-sat", I2C_NAME_SIZE-1); 256 257 if (i2c_attach_client(&sat->i2c)) { 258 printk(KERN_ERR "windfarm: failed to attach smu-sat to i2c\n"); 259 goto fail; 260 } 261 262 vsens[0] = vsens[1] = -1; 263 isens[0] = isens[1] = -1; 264 child = NULL; 265 while ((child = of_get_next_child(dev, child)) != NULL) { 266 reg = of_get_property(child, "reg", NULL); 267 type = of_get_property(child, "device_type", NULL); 268 loc = of_get_property(child, "location", NULL); 269 if (reg == NULL || loc == NULL) 270 continue; 271 272 /* the cooked sensors are between 0x30 and 0x37 */ 273 if (*reg < 0x30 || *reg > 0x37) 274 continue; 275 index = *reg - 0x30; 276 277 /* expect location to be CPU [AB][01] ... */ 278 if (strncmp(loc, "CPU ", 4) != 0) 279 continue; 280 chip = loc[4] - 'A'; 281 core = loc[5] - '0'; 282 if (chip > 1 || core > 1) { 283 printk(KERN_ERR "wf_sat_create: don't understand " 284 "location %s for %s\n", loc, child->full_name); 285 continue; 286 } 287 cpu = 2 * chip + core; 288 if (sat->nr < 0) 289 sat->nr = chip; 290 else if (sat->nr != chip) { 291 printk(KERN_ERR "wf_sat_create: can't cope with " 292 "multiple CPU chips on one SAT (%s)\n", loc); 293 continue; 294 } 295 296 if (strcmp(type, "voltage-sensor") == 0) { 297 name = "cpu-voltage"; 298 shift = 4; 299 vsens[core] = index; 300 } else if (strcmp(type, "current-sensor") == 0) { 301 name = "cpu-current"; 302 shift = 8; 303 isens[core] = index; 304 } else if (strcmp(type, "temp-sensor") == 0) { 305 name = "cpu-temp"; 306 shift = 10; 307 } else 308 continue; /* hmmm shouldn't happen */ 309 310 /* the +16 is enough for "cpu-voltage-n" */ 311 sens = kzalloc(sizeof(struct wf_sat_sensor) + 16, GFP_KERNEL); 312 if (sens == NULL) { 313 printk(KERN_ERR "wf_sat_create: couldn't create " 314 "%s sensor %d (no memory)\n", name, cpu); 315 continue; 316 } 317 sens->index = index; 318 sens->index2 = -1; 319 sens->shift = shift; 320 sens->sat = sat; 321 atomic_inc(&sat->refcnt); 322 sens->sens.ops = &wf_sat_ops; 323 sens->sens.name = (char *) (sens + 1); 324 snprintf(sens->sens.name, 16, "%s-%d", name, cpu); 325 326 if (wf_register_sensor(&sens->sens)) { 327 atomic_dec(&sat->refcnt); 328 kfree(sens); 329 } 330 } 331 332 /* make the power sensors */ 333 for (core = 0; core < 2; ++core) { 334 if (vsens[core] < 0 || isens[core] < 0) 335 continue; 336 cpu = 2 * sat->nr + core; 337 sens = kzalloc(sizeof(struct wf_sat_sensor) + 16, GFP_KERNEL); 338 if (sens == NULL) { 339 printk(KERN_ERR "wf_sat_create: couldn't create power " 340 "sensor %d (no memory)\n", cpu); 341 continue; 342 } 343 sens->index = vsens[core]; 344 sens->index2 = isens[core]; 345 sens->shift = 0; 346 sens->sat = sat; 347 atomic_inc(&sat->refcnt); 348 sens->sens.ops = &wf_sat_ops; 349 sens->sens.name = (char *) (sens + 1); 350 snprintf(sens->sens.name, 16, "cpu-power-%d", cpu); 351 352 if (wf_register_sensor(&sens->sens)) { 353 atomic_dec(&sat->refcnt); 354 kfree(sens); 355 } 356 } 357 358 if (sat->nr >= 0) 359 sats[sat->nr] = sat; 360 361 return; 362 363 fail: 364 kfree(sat); 365} 366 367static int wf_sat_attach(struct i2c_adapter *adapter) 368{ 369 struct device_node *busnode, *dev = NULL; 370 struct pmac_i2c_bus *bus; 371 372 bus = pmac_i2c_adapter_to_bus(adapter); 373 if (bus == NULL) 374 return -ENODEV; 375 busnode = pmac_i2c_get_bus_node(bus); 376 377 while ((dev = of_get_next_child(busnode, dev)) != NULL) 378 if (of_device_is_compatible(dev, "smu-sat")) 379 wf_sat_create(adapter, dev); 380 return 0; 381} 382 383static int wf_sat_detach(struct i2c_client *client) 384{ 385 struct wf_sat *sat = i2c_to_sat(client); 386 387 388 sat->i2c.adapter = NULL; 389 return 0; 390} 391 392static int __init sat_sensors_init(void) 393{ 394 return i2c_add_driver(&wf_sat_driver); 395} 396 397static void __exit sat_sensors_exit(void) 398{ 399 i2c_del_driver(&wf_sat_driver); 400} 401 402module_init(sat_sensors_init); 403/*module_exit(sat_sensors_exit); Uncomment when cleanup is implemented */ 404 405MODULE_AUTHOR("Paul Mackerras <paulus@samba.org>"); 406MODULE_DESCRIPTION("SMU satellite sensors for PowerMac thermal control"); 407MODULE_LICENSE("GPL"); 408