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 kfree(sat); 175 } 176 177 static void wf_sat_sensor_release(struct wf_sensor *sr) 178 { 179 struct wf_sat_sensor *sens = wf_to_sat(sr); 180 struct wf_sat *sat = sens->sat; 181 182 kfree(sens); 183 kref_put(&sat->ref, wf_sat_release); 184 } 185 186 static const struct wf_sensor_ops wf_sat_ops = { 187 .get_value = wf_sat_sensor_get, 188 .release = wf_sat_sensor_release, 189 .owner = THIS_MODULE, 190 }; 191 192 static int wf_sat_probe(struct i2c_client *client) 193 { 194 struct device_node *dev = client->dev.of_node; 195 struct wf_sat *sat; 196 struct wf_sat_sensor *sens; 197 const u32 *reg; 198 const char *loc; 199 u8 chip, core; 200 struct device_node *child; 201 int shift, cpu, index; 202 char *name; 203 int vsens[2], isens[2]; 204 205 sat = kzalloc(sizeof(struct wf_sat), GFP_KERNEL); 206 if (sat == NULL) 207 return -ENOMEM; 208 sat->nr = -1; 209 sat->node = of_node_get(dev); 210 kref_init(&sat->ref); 211 mutex_init(&sat->mutex); 212 sat->i2c = client; 213 INIT_LIST_HEAD(&sat->sensors); 214 i2c_set_clientdata(client, sat); 215 216 vsens[0] = vsens[1] = -1; 217 isens[0] = isens[1] = -1; 218 for_each_child_of_node(dev, child) { 219 reg = of_get_property(child, "reg", NULL); 220 loc = of_get_property(child, "location", NULL); 221 if (reg == NULL || loc == NULL) 222 continue; 223 224 /* the cooked sensors are between 0x30 and 0x37 */ 225 if (*reg < 0x30 || *reg > 0x37) 226 continue; 227 index = *reg - 0x30; 228 229 /* expect location to be CPU [AB][01] ... */ 230 if (strncmp(loc, "CPU ", 4) != 0) 231 continue; 232 chip = loc[4] - 'A'; 233 core = loc[5] - '0'; 234 if (chip > 1 || core > 1) { 235 printk(KERN_ERR "wf_sat_create: don't understand " 236 "location %s for %pOF\n", loc, child); 237 continue; 238 } 239 cpu = 2 * chip + core; 240 if (sat->nr < 0) 241 sat->nr = chip; 242 else if (sat->nr != chip) { 243 printk(KERN_ERR "wf_sat_create: can't cope with " 244 "multiple CPU chips on one SAT (%s)\n", loc); 245 continue; 246 } 247 248 if (of_node_is_type(child, "voltage-sensor")) { 249 name = "cpu-voltage"; 250 shift = 4; 251 vsens[core] = index; 252 } else if (of_node_is_type(child, "current-sensor")) { 253 name = "cpu-current"; 254 shift = 8; 255 isens[core] = index; 256 } else if (of_node_is_type(child, "temp-sensor")) { 257 name = "cpu-temp"; 258 shift = 10; 259 } else 260 continue; /* hmmm shouldn't happen */ 261 262 /* the +16 is enough for "cpu-voltage-n" */ 263 sens = kzalloc(sizeof(struct wf_sat_sensor) + 16, GFP_KERNEL); 264 if (sens == NULL) { 265 printk(KERN_ERR "wf_sat_create: couldn't create " 266 "%s sensor %d (no memory)\n", name, cpu); 267 continue; 268 } 269 sens->index = index; 270 sens->index2 = -1; 271 sens->shift = shift; 272 sens->sat = sat; 273 sens->sens.ops = &wf_sat_ops; 274 sens->sens.name = (char *) (sens + 1); 275 snprintf((char *)sens->sens.name, 16, "%s-%d", name, cpu); 276 277 if (wf_register_sensor(&sens->sens)) 278 kfree(sens); 279 else { 280 list_add(&sens->link, &sat->sensors); 281 kref_get(&sat->ref); 282 } 283 } 284 285 /* make the power sensors */ 286 for (core = 0; core < 2; ++core) { 287 if (vsens[core] < 0 || isens[core] < 0) 288 continue; 289 cpu = 2 * sat->nr + core; 290 sens = kzalloc(sizeof(struct wf_sat_sensor) + 16, GFP_KERNEL); 291 if (sens == NULL) { 292 printk(KERN_ERR "wf_sat_create: couldn't create power " 293 "sensor %d (no memory)\n", cpu); 294 continue; 295 } 296 sens->index = vsens[core]; 297 sens->index2 = isens[core]; 298 sens->shift = 0; 299 sens->sat = sat; 300 sens->sens.ops = &wf_sat_ops; 301 sens->sens.name = (char *) (sens + 1); 302 snprintf((char *)sens->sens.name, 16, "cpu-power-%d", cpu); 303 304 if (wf_register_sensor(&sens->sens)) 305 kfree(sens); 306 else { 307 list_add(&sens->link, &sat->sensors); 308 kref_get(&sat->ref); 309 } 310 } 311 312 if (sat->nr >= 0) 313 sats[sat->nr] = sat; 314 315 return 0; 316 } 317 318 static void wf_sat_remove(struct i2c_client *client) 319 { 320 struct wf_sat *sat = i2c_get_clientdata(client); 321 struct wf_sat_sensor *sens; 322 323 /* release sensors */ 324 while(!list_empty(&sat->sensors)) { 325 sens = list_first_entry(&sat->sensors, 326 struct wf_sat_sensor, link); 327 list_del(&sens->link); 328 wf_unregister_sensor(&sens->sens); 329 } 330 sat->i2c = NULL; 331 kref_put(&sat->ref, wf_sat_release); 332 } 333 334 static const struct i2c_device_id wf_sat_id[] = { 335 { "MAC,smu-sat", 0 }, 336 { } 337 }; 338 MODULE_DEVICE_TABLE(i2c, wf_sat_id); 339 340 static const struct of_device_id wf_sat_of_id[] = { 341 { .compatible = "smu-sat", }, 342 { } 343 }; 344 MODULE_DEVICE_TABLE(of, wf_sat_of_id); 345 346 static struct i2c_driver wf_sat_driver = { 347 .driver = { 348 .name = "wf_smu_sat", 349 .of_match_table = wf_sat_of_id, 350 }, 351 .probe_new = wf_sat_probe, 352 .remove = wf_sat_remove, 353 .id_table = wf_sat_id, 354 }; 355 356 module_i2c_driver(wf_sat_driver); 357 358 MODULE_AUTHOR("Paul Mackerras <paulus@samba.org>"); 359 MODULE_DESCRIPTION("SMU satellite sensors for PowerMac thermal control"); 360 MODULE_LICENSE("GPL"); 361