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 36 struct 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 46 static struct wf_sat *sats[2]; 47 48 struct 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 59 static int wf_sat_attach(struct i2c_adapter *adapter); 60 static int wf_sat_detach(struct i2c_client *client); 61 62 static 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 70 /* 71 * XXX i2c_smbus_read_i2c_block_data doesn't pass the requested 72 * length down to the low-level driver, so we use this, which 73 * works well enough with the SMU i2c driver code... 74 */ 75 static int sat_read_block(struct i2c_client *client, u8 command, 76 u8 *values, int len) 77 { 78 union i2c_smbus_data data; 79 int err; 80 81 data.block[0] = len; 82 err = i2c_smbus_xfer(client->adapter, client->addr, client->flags, 83 I2C_SMBUS_READ, command, I2C_SMBUS_I2C_BLOCK_DATA, 84 &data); 85 if (!err) 86 memcpy(values, data.block, len); 87 return err; 88 } 89 90 struct smu_sdbp_header *smu_sat_get_sdb_partition(unsigned int sat_id, int id, 91 unsigned int *size) 92 { 93 struct wf_sat *sat; 94 int err; 95 unsigned int i, len; 96 u8 *buf; 97 u8 data[4]; 98 99 /* TODO: Add the resulting partition to the device-tree */ 100 101 if (sat_id > 1 || (sat = sats[sat_id]) == NULL) 102 return NULL; 103 104 err = i2c_smbus_write_word_data(&sat->i2c, 8, id << 8); 105 if (err) { 106 printk(KERN_ERR "smu_sat_get_sdb_part wr error %d\n", err); 107 return NULL; 108 } 109 110 len = i2c_smbus_read_word_data(&sat->i2c, 9); 111 if (len < 0) { 112 printk(KERN_ERR "smu_sat_get_sdb_part rd len error\n"); 113 return NULL; 114 } 115 if (len == 0) { 116 printk(KERN_ERR "smu_sat_get_sdb_part no partition %x\n", id); 117 return NULL; 118 } 119 120 len = le16_to_cpu(len); 121 len = (len + 3) & ~3; 122 buf = kmalloc(len, GFP_KERNEL); 123 if (buf == NULL) 124 return NULL; 125 126 for (i = 0; i < len; i += 4) { 127 err = sat_read_block(&sat->i2c, 0xa, data, 4); 128 if (err) { 129 printk(KERN_ERR "smu_sat_get_sdb_part rd err %d\n", 130 err); 131 goto fail; 132 } 133 buf[i] = data[1]; 134 buf[i+1] = data[0]; 135 buf[i+2] = data[3]; 136 buf[i+3] = data[2]; 137 } 138 #ifdef DEBUG 139 DBG(KERN_DEBUG "sat %d partition %x:", sat_id, id); 140 for (i = 0; i < len; ++i) 141 DBG(" %x", buf[i]); 142 DBG("\n"); 143 #endif 144 145 if (size) 146 *size = len; 147 return (struct smu_sdbp_header *) buf; 148 149 fail: 150 kfree(buf); 151 return NULL; 152 } 153 EXPORT_SYMBOL_GPL(smu_sat_get_sdb_partition); 154 155 /* refresh the cache */ 156 static int wf_sat_read_cache(struct wf_sat *sat) 157 { 158 int err; 159 160 err = sat_read_block(&sat->i2c, 0x3f, sat->cache, 16); 161 if (err) 162 return err; 163 sat->last_read = jiffies; 164 #ifdef LOTSA_DEBUG 165 { 166 int i; 167 DBG(KERN_DEBUG "wf_sat_get: data is"); 168 for (i = 0; i < 16; ++i) 169 DBG(" %.2x", sat->cache[i]); 170 DBG("\n"); 171 } 172 #endif 173 return 0; 174 } 175 176 static int wf_sat_get(struct wf_sensor *sr, s32 *value) 177 { 178 struct wf_sat_sensor *sens = wf_to_sat(sr); 179 struct wf_sat *sat = sens->sat; 180 int i, err; 181 s32 val; 182 183 if (sat->i2c.adapter == NULL) 184 return -ENODEV; 185 186 down(&sat->mutex); 187 if (time_after(jiffies, (sat->last_read + MAX_AGE))) { 188 err = wf_sat_read_cache(sat); 189 if (err) 190 goto fail; 191 } 192 193 i = sens->index * 2; 194 val = ((sat->cache[i] << 8) + sat->cache[i+1]) << sens->shift; 195 if (sens->index2 >= 0) { 196 i = sens->index2 * 2; 197 /* 4.12 * 8.8 -> 12.20; shift right 4 to get 16.16 */ 198 val = (val * ((sat->cache[i] << 8) + sat->cache[i+1])) >> 4; 199 } 200 201 *value = val; 202 err = 0; 203 204 fail: 205 up(&sat->mutex); 206 return err; 207 } 208 209 static void wf_sat_release(struct wf_sensor *sr) 210 { 211 struct wf_sat_sensor *sens = wf_to_sat(sr); 212 struct wf_sat *sat = sens->sat; 213 214 if (atomic_dec_and_test(&sat->refcnt)) { 215 if (sat->i2c.adapter) { 216 i2c_detach_client(&sat->i2c); 217 sat->i2c.adapter = NULL; 218 } 219 if (sat->nr >= 0) 220 sats[sat->nr] = NULL; 221 kfree(sat); 222 } 223 kfree(sens); 224 } 225 226 static struct wf_sensor_ops wf_sat_ops = { 227 .get_value = wf_sat_get, 228 .release = wf_sat_release, 229 .owner = THIS_MODULE, 230 }; 231 232 static void wf_sat_create(struct i2c_adapter *adapter, struct device_node *dev) 233 { 234 struct wf_sat *sat; 235 struct wf_sat_sensor *sens; 236 const u32 *reg; 237 const char *loc, *type; 238 u8 addr, chip, core; 239 struct device_node *child; 240 int shift, cpu, index; 241 char *name; 242 int vsens[2], isens[2]; 243 244 reg = of_get_property(dev, "reg", NULL); 245 if (reg == NULL) 246 return; 247 addr = *reg; 248 DBG(KERN_DEBUG "wf_sat: creating sat at address %x\n", addr); 249 250 sat = kzalloc(sizeof(struct wf_sat), GFP_KERNEL); 251 if (sat == NULL) 252 return; 253 sat->nr = -1; 254 sat->node = of_node_get(dev); 255 atomic_set(&sat->refcnt, 0); 256 init_MUTEX(&sat->mutex); 257 sat->i2c.addr = (addr >> 1) & 0x7f; 258 sat->i2c.adapter = adapter; 259 sat->i2c.driver = &wf_sat_driver; 260 strncpy(sat->i2c.name, "smu-sat", I2C_NAME_SIZE-1); 261 262 if (i2c_attach_client(&sat->i2c)) { 263 printk(KERN_ERR "windfarm: failed to attach smu-sat to i2c\n"); 264 goto fail; 265 } 266 267 vsens[0] = vsens[1] = -1; 268 isens[0] = isens[1] = -1; 269 child = NULL; 270 while ((child = of_get_next_child(dev, child)) != NULL) { 271 reg = of_get_property(child, "reg", NULL); 272 type = of_get_property(child, "device_type", NULL); 273 loc = of_get_property(child, "location", NULL); 274 if (reg == NULL || loc == NULL) 275 continue; 276 277 /* the cooked sensors are between 0x30 and 0x37 */ 278 if (*reg < 0x30 || *reg > 0x37) 279 continue; 280 index = *reg - 0x30; 281 282 /* expect location to be CPU [AB][01] ... */ 283 if (strncmp(loc, "CPU ", 4) != 0) 284 continue; 285 chip = loc[4] - 'A'; 286 core = loc[5] - '0'; 287 if (chip > 1 || core > 1) { 288 printk(KERN_ERR "wf_sat_create: don't understand " 289 "location %s for %s\n", loc, child->full_name); 290 continue; 291 } 292 cpu = 2 * chip + core; 293 if (sat->nr < 0) 294 sat->nr = chip; 295 else if (sat->nr != chip) { 296 printk(KERN_ERR "wf_sat_create: can't cope with " 297 "multiple CPU chips on one SAT (%s)\n", loc); 298 continue; 299 } 300 301 if (strcmp(type, "voltage-sensor") == 0) { 302 name = "cpu-voltage"; 303 shift = 4; 304 vsens[core] = index; 305 } else if (strcmp(type, "current-sensor") == 0) { 306 name = "cpu-current"; 307 shift = 8; 308 isens[core] = index; 309 } else if (strcmp(type, "temp-sensor") == 0) { 310 name = "cpu-temp"; 311 shift = 10; 312 } else 313 continue; /* hmmm shouldn't happen */ 314 315 /* the +16 is enough for "cpu-voltage-n" */ 316 sens = kzalloc(sizeof(struct wf_sat_sensor) + 16, GFP_KERNEL); 317 if (sens == NULL) { 318 printk(KERN_ERR "wf_sat_create: couldn't create " 319 "%s sensor %d (no memory)\n", name, cpu); 320 continue; 321 } 322 sens->index = index; 323 sens->index2 = -1; 324 sens->shift = shift; 325 sens->sat = sat; 326 atomic_inc(&sat->refcnt); 327 sens->sens.ops = &wf_sat_ops; 328 sens->sens.name = (char *) (sens + 1); 329 snprintf(sens->sens.name, 16, "%s-%d", name, cpu); 330 331 if (wf_register_sensor(&sens->sens)) { 332 atomic_dec(&sat->refcnt); 333 kfree(sens); 334 } 335 } 336 337 /* make the power sensors */ 338 for (core = 0; core < 2; ++core) { 339 if (vsens[core] < 0 || isens[core] < 0) 340 continue; 341 cpu = 2 * sat->nr + core; 342 sens = kzalloc(sizeof(struct wf_sat_sensor) + 16, GFP_KERNEL); 343 if (sens == NULL) { 344 printk(KERN_ERR "wf_sat_create: couldn't create power " 345 "sensor %d (no memory)\n", cpu); 346 continue; 347 } 348 sens->index = vsens[core]; 349 sens->index2 = isens[core]; 350 sens->shift = 0; 351 sens->sat = sat; 352 atomic_inc(&sat->refcnt); 353 sens->sens.ops = &wf_sat_ops; 354 sens->sens.name = (char *) (sens + 1); 355 snprintf(sens->sens.name, 16, "cpu-power-%d", cpu); 356 357 if (wf_register_sensor(&sens->sens)) { 358 atomic_dec(&sat->refcnt); 359 kfree(sens); 360 } 361 } 362 363 if (sat->nr >= 0) 364 sats[sat->nr] = sat; 365 366 return; 367 368 fail: 369 kfree(sat); 370 } 371 372 static int wf_sat_attach(struct i2c_adapter *adapter) 373 { 374 struct device_node *busnode, *dev = NULL; 375 struct pmac_i2c_bus *bus; 376 377 bus = pmac_i2c_adapter_to_bus(adapter); 378 if (bus == NULL) 379 return -ENODEV; 380 busnode = pmac_i2c_get_bus_node(bus); 381 382 while ((dev = of_get_next_child(busnode, dev)) != NULL) 383 if (of_device_is_compatible(dev, "smu-sat")) 384 wf_sat_create(adapter, dev); 385 return 0; 386 } 387 388 static int wf_sat_detach(struct i2c_client *client) 389 { 390 struct wf_sat *sat = i2c_to_sat(client); 391 392 /* XXX TODO */ 393 394 sat->i2c.adapter = NULL; 395 return 0; 396 } 397 398 static int __init sat_sensors_init(void) 399 { 400 return i2c_add_driver(&wf_sat_driver); 401 } 402 403 static void __exit sat_sensors_exit(void) 404 { 405 i2c_del_driver(&wf_sat_driver); 406 } 407 408 module_init(sat_sensors_init); 409 /*module_exit(sat_sensors_exit); Uncomment when cleanup is implemented */ 410 411 MODULE_AUTHOR("Paul Mackerras <paulus@samba.org>"); 412 MODULE_DESCRIPTION("SMU satellite sensors for PowerMac thermal control"); 413 MODULE_LICENSE("GPL"); 414