1 // SPDX-License-Identifier: GPL-2.0-only 2 /* 3 * Windfarm PowerMac thermal control. SMU "satellite" controller sensors. 4 * 5 * Copyright (C) 2005 Paul Mackerras, IBM Corp. <paulus@samba.org> 6 */ 7 8 #include <linux/types.h> 9 #include <linux/errno.h> 10 #include <linux/kernel.h> 11 #include <linux/slab.h> 12 #include <linux/init.h> 13 #include <linux/wait.h> 14 #include <linux/i2c.h> 15 #include <linux/mutex.h> 16 17 #include <asm/smu.h> 18 #include <asm/pmac_low_i2c.h> 19 20 #include "windfarm.h" 21 22 #define VERSION "1.0" 23 24 /* If the cache is older than 800ms we'll refetch it */ 25 #define MAX_AGE msecs_to_jiffies(800) 26 27 struct wf_sat { 28 struct kref ref; 29 int nr; 30 struct mutex mutex; 31 unsigned long last_read; /* jiffies when cache last updated */ 32 u8 cache[16]; 33 struct list_head sensors; 34 struct i2c_client *i2c; 35 struct device_node *node; 36 }; 37 38 static struct wf_sat *sats[2]; 39 40 struct wf_sat_sensor { 41 struct list_head link; 42 int index; 43 int index2; /* used for power sensors */ 44 int shift; 45 struct wf_sat *sat; 46 struct wf_sensor sens; 47 }; 48 49 #define wf_to_sat(c) container_of(c, struct wf_sat_sensor, sens) 50 51 struct smu_sdbp_header *smu_sat_get_sdb_partition(unsigned int sat_id, int id, 52 unsigned int *size) 53 { 54 struct wf_sat *sat; 55 int err; 56 unsigned int i, len; 57 u8 *buf; 58 u8 data[4]; 59 60 /* TODO: Add the resulting partition to the device-tree */ 61 62 if (sat_id > 1 || (sat = sats[sat_id]) == NULL) 63 return NULL; 64 65 err = i2c_smbus_write_word_data(sat->i2c, 8, id << 8); 66 if (err) { 67 printk(KERN_ERR "smu_sat_get_sdb_part wr error %d\n", err); 68 return NULL; 69 } 70 71 err = i2c_smbus_read_word_data(sat->i2c, 9); 72 if (err < 0) { 73 printk(KERN_ERR "smu_sat_get_sdb_part rd len error\n"); 74 return NULL; 75 } 76 len = err; 77 if (len == 0) { 78 printk(KERN_ERR "smu_sat_get_sdb_part no partition %x\n", id); 79 return NULL; 80 } 81 82 len = le16_to_cpu(len); 83 len = (len + 3) & ~3; 84 buf = kmalloc(len, GFP_KERNEL); 85 if (buf == NULL) 86 return NULL; 87 88 for (i = 0; i < len; i += 4) { 89 err = i2c_smbus_read_i2c_block_data(sat->i2c, 0xa, 4, data); 90 if (err < 0) { 91 printk(KERN_ERR "smu_sat_get_sdb_part rd err %d\n", 92 err); 93 goto fail; 94 } 95 buf[i] = data[1]; 96 buf[i+1] = data[0]; 97 buf[i+2] = data[3]; 98 buf[i+3] = data[2]; 99 } 100 101 printk(KERN_DEBUG "sat %d partition %x:", sat_id, id); 102 print_hex_dump(KERN_DEBUG, " ", DUMP_PREFIX_OFFSET, 103 16, 1, buf, len, false); 104 if (size) 105 *size = len; 106 return (struct smu_sdbp_header *) buf; 107 108 fail: 109 kfree(buf); 110 return NULL; 111 } 112 EXPORT_SYMBOL_GPL(smu_sat_get_sdb_partition); 113 114 /* refresh the cache */ 115 static int wf_sat_read_cache(struct wf_sat *sat) 116 { 117 int err; 118 119 err = i2c_smbus_read_i2c_block_data(sat->i2c, 0x3f, 16, sat->cache); 120 if (err < 0) 121 return err; 122 sat->last_read = jiffies; 123 124 #ifdef LOTSA_DEBUG 125 { 126 int i; 127 printk(KERN_DEBUG "wf_sat_get: data is"); 128 print_hex_dump(KERN_DEBUG, " ", DUMP_PREFIX_OFFSET, 129 16, 1, sat->cache, 16, false); 130 } 131 #endif 132 return 0; 133 } 134 135 static int wf_sat_sensor_get(struct wf_sensor *sr, s32 *value) 136 { 137 struct wf_sat_sensor *sens = wf_to_sat(sr); 138 struct wf_sat *sat = sens->sat; 139 int i, err; 140 s32 val; 141 142 if (sat->i2c == NULL) 143 return -ENODEV; 144 145 mutex_lock(&sat->mutex); 146 if (time_after(jiffies, (sat->last_read + MAX_AGE))) { 147 err = wf_sat_read_cache(sat); 148 if (err) 149 goto fail; 150 } 151 152 i = sens->index * 2; 153 val = ((sat->cache[i] << 8) + sat->cache[i+1]) << sens->shift; 154 if (sens->index2 >= 0) { 155 i = sens->index2 * 2; 156 /* 4.12 * 8.8 -> 12.20; shift right 4 to get 16.16 */ 157 val = (val * ((sat->cache[i] << 8) + sat->cache[i+1])) >> 4; 158 } 159 160 *value = val; 161 err = 0; 162 163 fail: 164 mutex_unlock(&sat->mutex); 165 return err; 166 } 167 168 static void wf_sat_release(struct kref *ref) 169 { 170 struct wf_sat *sat = container_of(ref, struct wf_sat, ref); 171 172 if (sat->nr >= 0) 173 sats[sat->nr] = NULL; 174 of_node_put(sat->node); 175 kfree(sat); 176 } 177 178 static void wf_sat_sensor_release(struct wf_sensor *sr) 179 { 180 struct wf_sat_sensor *sens = wf_to_sat(sr); 181 struct wf_sat *sat = sens->sat; 182 183 kfree(sens); 184 kref_put(&sat->ref, wf_sat_release); 185 } 186 187 static const struct wf_sensor_ops wf_sat_ops = { 188 .get_value = wf_sat_sensor_get, 189 .release = wf_sat_sensor_release, 190 .owner = THIS_MODULE, 191 }; 192 193 static int wf_sat_probe(struct i2c_client *client) 194 { 195 struct device_node *dev = client->dev.of_node; 196 struct wf_sat *sat; 197 struct wf_sat_sensor *sens; 198 const u32 *reg; 199 const char *loc; 200 u8 chip, core; 201 struct device_node *child; 202 int shift, cpu, index; 203 char *name; 204 int vsens[2], isens[2]; 205 206 sat = kzalloc(sizeof(struct wf_sat), GFP_KERNEL); 207 if (sat == NULL) 208 return -ENOMEM; 209 sat->nr = -1; 210 sat->node = of_node_get(dev); 211 kref_init(&sat->ref); 212 mutex_init(&sat->mutex); 213 sat->i2c = client; 214 INIT_LIST_HEAD(&sat->sensors); 215 i2c_set_clientdata(client, sat); 216 217 vsens[0] = vsens[1] = -1; 218 isens[0] = isens[1] = -1; 219 for_each_child_of_node(dev, child) { 220 reg = of_get_property(child, "reg", NULL); 221 loc = of_get_property(child, "location", NULL); 222 if (reg == NULL || loc == NULL) 223 continue; 224 225 /* the cooked sensors are between 0x30 and 0x37 */ 226 if (*reg < 0x30 || *reg > 0x37) 227 continue; 228 index = *reg - 0x30; 229 230 /* expect location to be CPU [AB][01] ... */ 231 if (strncmp(loc, "CPU ", 4) != 0) 232 continue; 233 chip = loc[4] - 'A'; 234 core = loc[5] - '0'; 235 if (chip > 1 || core > 1) { 236 printk(KERN_ERR "wf_sat_create: don't understand " 237 "location %s for %pOF\n", loc, child); 238 continue; 239 } 240 cpu = 2 * chip + core; 241 if (sat->nr < 0) 242 sat->nr = chip; 243 else if (sat->nr != chip) { 244 printk(KERN_ERR "wf_sat_create: can't cope with " 245 "multiple CPU chips on one SAT (%s)\n", loc); 246 continue; 247 } 248 249 if (of_node_is_type(child, "voltage-sensor")) { 250 name = "cpu-voltage"; 251 shift = 4; 252 vsens[core] = index; 253 } else if (of_node_is_type(child, "current-sensor")) { 254 name = "cpu-current"; 255 shift = 8; 256 isens[core] = index; 257 } else if (of_node_is_type(child, "temp-sensor")) { 258 name = "cpu-temp"; 259 shift = 10; 260 } else 261 continue; /* hmmm shouldn't happen */ 262 263 /* the +16 is enough for "cpu-voltage-n" */ 264 sens = kzalloc(sizeof(struct wf_sat_sensor) + 16, GFP_KERNEL); 265 if (sens == NULL) { 266 printk(KERN_ERR "wf_sat_create: couldn't create " 267 "%s sensor %d (no memory)\n", name, cpu); 268 continue; 269 } 270 sens->index = index; 271 sens->index2 = -1; 272 sens->shift = shift; 273 sens->sat = sat; 274 sens->sens.ops = &wf_sat_ops; 275 sens->sens.name = (char *) (sens + 1); 276 snprintf((char *)sens->sens.name, 16, "%s-%d", name, cpu); 277 278 if (wf_register_sensor(&sens->sens)) 279 kfree(sens); 280 else { 281 list_add(&sens->link, &sat->sensors); 282 kref_get(&sat->ref); 283 } 284 } 285 286 /* make the power sensors */ 287 for (core = 0; core < 2; ++core) { 288 if (vsens[core] < 0 || isens[core] < 0) 289 continue; 290 cpu = 2 * sat->nr + core; 291 sens = kzalloc(sizeof(struct wf_sat_sensor) + 16, GFP_KERNEL); 292 if (sens == NULL) { 293 printk(KERN_ERR "wf_sat_create: couldn't create power " 294 "sensor %d (no memory)\n", cpu); 295 continue; 296 } 297 sens->index = vsens[core]; 298 sens->index2 = isens[core]; 299 sens->shift = 0; 300 sens->sat = sat; 301 sens->sens.ops = &wf_sat_ops; 302 sens->sens.name = (char *) (sens + 1); 303 snprintf((char *)sens->sens.name, 16, "cpu-power-%d", cpu); 304 305 if (wf_register_sensor(&sens->sens)) 306 kfree(sens); 307 else { 308 list_add(&sens->link, &sat->sensors); 309 kref_get(&sat->ref); 310 } 311 } 312 313 if (sat->nr >= 0) 314 sats[sat->nr] = sat; 315 316 return 0; 317 } 318 319 static void wf_sat_remove(struct i2c_client *client) 320 { 321 struct wf_sat *sat = i2c_get_clientdata(client); 322 struct wf_sat_sensor *sens; 323 324 /* release sensors */ 325 while(!list_empty(&sat->sensors)) { 326 sens = list_first_entry(&sat->sensors, 327 struct wf_sat_sensor, link); 328 list_del(&sens->link); 329 wf_unregister_sensor(&sens->sens); 330 } 331 sat->i2c = NULL; 332 kref_put(&sat->ref, wf_sat_release); 333 } 334 335 static const struct i2c_device_id wf_sat_id[] = { 336 { "MAC,smu-sat", 0 }, 337 { } 338 }; 339 MODULE_DEVICE_TABLE(i2c, wf_sat_id); 340 341 static const struct of_device_id wf_sat_of_id[] = { 342 { .compatible = "smu-sat", }, 343 { } 344 }; 345 MODULE_DEVICE_TABLE(of, wf_sat_of_id); 346 347 static struct i2c_driver wf_sat_driver = { 348 .driver = { 349 .name = "wf_smu_sat", 350 .of_match_table = wf_sat_of_id, 351 }, 352 .probe = wf_sat_probe, 353 .remove = wf_sat_remove, 354 .id_table = wf_sat_id, 355 }; 356 357 module_i2c_driver(wf_sat_driver); 358 359 MODULE_AUTHOR("Paul Mackerras <paulus@samba.org>"); 360 MODULE_DESCRIPTION("SMU satellite sensors for PowerMac thermal control"); 361 MODULE_LICENSE("GPL"); 362