1 // SPDX-License-Identifier: GPL-2.0-only 2 /* 3 * Windfarm PowerMac thermal control. SMU based controls 4 * 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 "0.4" 27 28 #undef DEBUG 29 30 #ifdef DEBUG 31 #define DBG(args...) printk(args) 32 #else 33 #define DBG(args...) do { } while(0) 34 #endif 35 36 static int smu_supports_new_fans_ops = 1; 37 38 /* 39 * SMU fans control object 40 */ 41 42 static LIST_HEAD(smu_fans); 43 44 struct smu_fan_control { 45 struct list_head link; 46 int fan_type; /* 0 = rpm, 1 = pwm */ 47 u32 reg; /* index in SMU */ 48 s32 value; /* current value */ 49 s32 min, max; /* min/max values */ 50 struct wf_control ctrl; 51 }; 52 #define to_smu_fan(c) container_of(c, struct smu_fan_control, ctrl) 53 54 static int smu_set_fan(int pwm, u8 id, u16 value) 55 { 56 struct smu_cmd cmd; 57 u8 buffer[16]; 58 DECLARE_COMPLETION_ONSTACK(comp); 59 int rc; 60 61 /* Fill SMU command structure */ 62 cmd.cmd = SMU_CMD_FAN_COMMAND; 63 64 /* The SMU has an "old" and a "new" way of setting the fan speed 65 * Unfortunately, I found no reliable way to know which one works 66 * on a given machine model. After some investigations it appears 67 * that MacOS X just tries the new one, and if it fails fallbacks 68 * to the old ones ... Ugh. 69 */ 70 retry: 71 if (smu_supports_new_fans_ops) { 72 buffer[0] = 0x30; 73 buffer[1] = id; 74 *((u16 *)(&buffer[2])) = value; 75 cmd.data_len = 4; 76 } else { 77 if (id > 7) 78 return -EINVAL; 79 /* Fill argument buffer */ 80 memset(buffer, 0, 16); 81 buffer[0] = pwm ? 0x10 : 0x00; 82 buffer[1] = 0x01 << id; 83 *((u16 *)&buffer[2 + id * 2]) = value; 84 cmd.data_len = 14; 85 } 86 87 cmd.reply_len = 16; 88 cmd.data_buf = cmd.reply_buf = buffer; 89 cmd.status = 0; 90 cmd.done = smu_done_complete; 91 cmd.misc = ∁ 92 93 rc = smu_queue_cmd(&cmd); 94 if (rc) 95 return rc; 96 wait_for_completion(&comp); 97 98 /* Handle fallback (see comment above) */ 99 if (cmd.status != 0 && smu_supports_new_fans_ops) { 100 printk(KERN_WARNING "windfarm: SMU failed new fan command " 101 "falling back to old method\n"); 102 smu_supports_new_fans_ops = 0; 103 goto retry; 104 } 105 106 return cmd.status; 107 } 108 109 static void smu_fan_release(struct wf_control *ct) 110 { 111 struct smu_fan_control *fct = to_smu_fan(ct); 112 113 kfree(fct); 114 } 115 116 static int smu_fan_set(struct wf_control *ct, s32 value) 117 { 118 struct smu_fan_control *fct = to_smu_fan(ct); 119 120 if (value < fct->min) 121 value = fct->min; 122 if (value > fct->max) 123 value = fct->max; 124 fct->value = value; 125 126 return smu_set_fan(fct->fan_type, fct->reg, value); 127 } 128 129 static int smu_fan_get(struct wf_control *ct, s32 *value) 130 { 131 struct smu_fan_control *fct = to_smu_fan(ct); 132 *value = fct->value; /* todo: read from SMU */ 133 return 0; 134 } 135 136 static s32 smu_fan_min(struct wf_control *ct) 137 { 138 struct smu_fan_control *fct = to_smu_fan(ct); 139 return fct->min; 140 } 141 142 static s32 smu_fan_max(struct wf_control *ct) 143 { 144 struct smu_fan_control *fct = to_smu_fan(ct); 145 return fct->max; 146 } 147 148 static const struct wf_control_ops smu_fan_ops = { 149 .set_value = smu_fan_set, 150 .get_value = smu_fan_get, 151 .get_min = smu_fan_min, 152 .get_max = smu_fan_max, 153 .release = smu_fan_release, 154 .owner = THIS_MODULE, 155 }; 156 157 static struct smu_fan_control *smu_fan_create(struct device_node *node, 158 int pwm_fan) 159 { 160 struct smu_fan_control *fct; 161 const s32 *v; 162 const u32 *reg; 163 const char *l; 164 165 fct = kmalloc(sizeof(struct smu_fan_control), GFP_KERNEL); 166 if (fct == NULL) 167 return NULL; 168 fct->ctrl.ops = &smu_fan_ops; 169 l = of_get_property(node, "location", NULL); 170 if (l == NULL) 171 goto fail; 172 173 fct->fan_type = pwm_fan; 174 fct->ctrl.type = pwm_fan ? WF_CONTROL_PWM_FAN : WF_CONTROL_RPM_FAN; 175 176 /* We use the name & location here the same way we do for SMU sensors, 177 * see the comment in windfarm_smu_sensors.c. The locations are a bit 178 * less consistent here between the iMac and the desktop models, but 179 * that is good enough for our needs for now at least. 180 * 181 * One problem though is that Apple seem to be inconsistent with case 182 * and the kernel doesn't have strcasecmp =P 183 */ 184 185 fct->ctrl.name = NULL; 186 187 /* Names used on desktop models */ 188 if (!strcmp(l, "Rear Fan 0") || !strcmp(l, "Rear Fan") || 189 !strcmp(l, "Rear fan 0") || !strcmp(l, "Rear fan") || 190 !strcmp(l, "CPU A EXHAUST")) 191 fct->ctrl.name = "cpu-rear-fan-0"; 192 else if (!strcmp(l, "Rear Fan 1") || !strcmp(l, "Rear fan 1") || 193 !strcmp(l, "CPU B EXHAUST")) 194 fct->ctrl.name = "cpu-rear-fan-1"; 195 else if (!strcmp(l, "Front Fan 0") || !strcmp(l, "Front Fan") || 196 !strcmp(l, "Front fan 0") || !strcmp(l, "Front fan") || 197 !strcmp(l, "CPU A INTAKE")) 198 fct->ctrl.name = "cpu-front-fan-0"; 199 else if (!strcmp(l, "Front Fan 1") || !strcmp(l, "Front fan 1") || 200 !strcmp(l, "CPU B INTAKE")) 201 fct->ctrl.name = "cpu-front-fan-1"; 202 else if (!strcmp(l, "CPU A PUMP")) 203 fct->ctrl.name = "cpu-pump-0"; 204 else if (!strcmp(l, "CPU B PUMP")) 205 fct->ctrl.name = "cpu-pump-1"; 206 else if (!strcmp(l, "Slots Fan") || !strcmp(l, "Slots fan") || 207 !strcmp(l, "EXPANSION SLOTS INTAKE")) 208 fct->ctrl.name = "slots-fan"; 209 else if (!strcmp(l, "Drive Bay") || !strcmp(l, "Drive bay") || 210 !strcmp(l, "DRIVE BAY A INTAKE")) 211 fct->ctrl.name = "drive-bay-fan"; 212 else if (!strcmp(l, "BACKSIDE")) 213 fct->ctrl.name = "backside-fan"; 214 215 /* Names used on iMac models */ 216 if (!strcmp(l, "System Fan") || !strcmp(l, "System fan")) 217 fct->ctrl.name = "system-fan"; 218 else if (!strcmp(l, "CPU Fan") || !strcmp(l, "CPU fan")) 219 fct->ctrl.name = "cpu-fan"; 220 else if (!strcmp(l, "Hard Drive") || !strcmp(l, "Hard drive")) 221 fct->ctrl.name = "drive-bay-fan"; 222 else if (!strcmp(l, "HDD Fan")) /* seen on iMac G5 iSight */ 223 fct->ctrl.name = "hard-drive-fan"; 224 else if (!strcmp(l, "ODD Fan")) /* same */ 225 fct->ctrl.name = "optical-drive-fan"; 226 227 /* Unrecognized fan, bail out */ 228 if (fct->ctrl.name == NULL) 229 goto fail; 230 231 /* Get min & max values*/ 232 v = of_get_property(node, "min-value", NULL); 233 if (v == NULL) 234 goto fail; 235 fct->min = *v; 236 v = of_get_property(node, "max-value", NULL); 237 if (v == NULL) 238 goto fail; 239 fct->max = *v; 240 241 /* Get "reg" value */ 242 reg = of_get_property(node, "reg", NULL); 243 if (reg == NULL) 244 goto fail; 245 fct->reg = *reg; 246 247 if (wf_register_control(&fct->ctrl)) 248 goto fail; 249 250 return fct; 251 fail: 252 kfree(fct); 253 return NULL; 254 } 255 256 257 static int __init smu_controls_init(void) 258 { 259 struct device_node *smu, *fans, *fan; 260 261 if (!smu_present()) 262 return -ENODEV; 263 264 smu = of_find_node_by_type(NULL, "smu"); 265 if (smu == NULL) 266 return -ENODEV; 267 268 /* Look for RPM fans */ 269 for_each_child_of_node(smu, fans) 270 if (of_node_name_eq(fans, "rpm-fans") || 271 of_device_is_compatible(fans, "smu-rpm-fans")) 272 break; 273 for_each_child_of_node(fans, fan) { 274 struct smu_fan_control *fct; 275 276 fct = smu_fan_create(fan, 0); 277 if (fct == NULL) { 278 printk(KERN_WARNING "windfarm: Failed to create SMU " 279 "RPM fan %pOFn\n", fan); 280 continue; 281 } 282 list_add(&fct->link, &smu_fans); 283 } 284 of_node_put(fans); 285 286 287 /* Look for PWM fans */ 288 for_each_child_of_node(smu, fans) 289 if (of_node_name_eq(fans, "pwm-fans")) 290 break; 291 for_each_child_of_node(fans, fan) { 292 struct smu_fan_control *fct; 293 294 fct = smu_fan_create(fan, 1); 295 if (fct == NULL) { 296 printk(KERN_WARNING "windfarm: Failed to create SMU " 297 "PWM fan %pOFn\n", fan); 298 continue; 299 } 300 list_add(&fct->link, &smu_fans); 301 } 302 of_node_put(fans); 303 of_node_put(smu); 304 305 return 0; 306 } 307 308 static void __exit smu_controls_exit(void) 309 { 310 struct smu_fan_control *fct; 311 312 while (!list_empty(&smu_fans)) { 313 fct = list_entry(smu_fans.next, struct smu_fan_control, link); 314 list_del(&fct->link); 315 wf_unregister_control(&fct->ctrl); 316 } 317 } 318 319 320 module_init(smu_controls_init); 321 module_exit(smu_controls_exit); 322 323 MODULE_AUTHOR("Benjamin Herrenschmidt <benh@kernel.crashing.org>"); 324 MODULE_DESCRIPTION("SMU control objects for PowerMacs thermal control"); 325 MODULE_LICENSE("GPL"); 326 327