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 <asm/prom.h>
18 #include <asm/machdep.h>
19 #include <asm/io.h>
20 #include <asm/sections.h>
21 #include <asm/smu.h>
22
23 #include "windfarm.h"
24
25 #define VERSION "0.4"
26
27 #undef DEBUG
28
29 #ifdef DEBUG
30 #define DBG(args...) printk(args)
31 #else
32 #define DBG(args...) do { } while(0)
33 #endif
34
35 static int smu_supports_new_fans_ops = 1;
36
37 /*
38 * SMU fans control object
39 */
40
41 static LIST_HEAD(smu_fans);
42
43 struct smu_fan_control {
44 struct list_head link;
45 int fan_type; /* 0 = rpm, 1 = pwm */
46 u32 reg; /* index in SMU */
47 s32 value; /* current value */
48 s32 min, max; /* min/max values */
49 struct wf_control ctrl;
50 };
51 #define to_smu_fan(c) container_of(c, struct smu_fan_control, ctrl)
52
smu_set_fan(int pwm,u8 id,u16 value)53 static int smu_set_fan(int pwm, u8 id, u16 value)
54 {
55 struct smu_cmd cmd;
56 u8 buffer[16];
57 DECLARE_COMPLETION_ONSTACK(comp);
58 int rc;
59
60 /* Fill SMU command structure */
61 cmd.cmd = SMU_CMD_FAN_COMMAND;
62
63 /* The SMU has an "old" and a "new" way of setting the fan speed
64 * Unfortunately, I found no reliable way to know which one works
65 * on a given machine model. After some investigations it appears
66 * that MacOS X just tries the new one, and if it fails fallbacks
67 * to the old ones ... Ugh.
68 */
69 retry:
70 if (smu_supports_new_fans_ops) {
71 buffer[0] = 0x30;
72 buffer[1] = id;
73 *((u16 *)(&buffer[2])) = value;
74 cmd.data_len = 4;
75 } else {
76 if (id > 7)
77 return -EINVAL;
78 /* Fill argument buffer */
79 memset(buffer, 0, 16);
80 buffer[0] = pwm ? 0x10 : 0x00;
81 buffer[1] = 0x01 << id;
82 *((u16 *)&buffer[2 + id * 2]) = value;
83 cmd.data_len = 14;
84 }
85
86 cmd.reply_len = 16;
87 cmd.data_buf = cmd.reply_buf = buffer;
88 cmd.status = 0;
89 cmd.done = smu_done_complete;
90 cmd.misc = ∁
91
92 rc = smu_queue_cmd(&cmd);
93 if (rc)
94 return rc;
95 wait_for_completion(&comp);
96
97 /* Handle fallback (see comment above) */
98 if (cmd.status != 0 && smu_supports_new_fans_ops) {
99 printk(KERN_WARNING "windfarm: SMU failed new fan command "
100 "falling back to old method\n");
101 smu_supports_new_fans_ops = 0;
102 goto retry;
103 }
104
105 return cmd.status;
106 }
107
smu_fan_release(struct wf_control * ct)108 static void smu_fan_release(struct wf_control *ct)
109 {
110 struct smu_fan_control *fct = to_smu_fan(ct);
111
112 kfree(fct);
113 }
114
smu_fan_set(struct wf_control * ct,s32 value)115 static int smu_fan_set(struct wf_control *ct, s32 value)
116 {
117 struct smu_fan_control *fct = to_smu_fan(ct);
118
119 if (value < fct->min)
120 value = fct->min;
121 if (value > fct->max)
122 value = fct->max;
123 fct->value = value;
124
125 return smu_set_fan(fct->fan_type, fct->reg, value);
126 }
127
smu_fan_get(struct wf_control * ct,s32 * value)128 static int smu_fan_get(struct wf_control *ct, s32 *value)
129 {
130 struct smu_fan_control *fct = to_smu_fan(ct);
131 *value = fct->value; /* todo: read from SMU */
132 return 0;
133 }
134
smu_fan_min(struct wf_control * ct)135 static s32 smu_fan_min(struct wf_control *ct)
136 {
137 struct smu_fan_control *fct = to_smu_fan(ct);
138 return fct->min;
139 }
140
smu_fan_max(struct wf_control * ct)141 static s32 smu_fan_max(struct wf_control *ct)
142 {
143 struct smu_fan_control *fct = to_smu_fan(ct);
144 return fct->max;
145 }
146
147 static const struct wf_control_ops smu_fan_ops = {
148 .set_value = smu_fan_set,
149 .get_value = smu_fan_get,
150 .get_min = smu_fan_min,
151 .get_max = smu_fan_max,
152 .release = smu_fan_release,
153 .owner = THIS_MODULE,
154 };
155
smu_fan_create(struct device_node * node,int pwm_fan)156 static struct smu_fan_control *smu_fan_create(struct device_node *node,
157 int pwm_fan)
158 {
159 struct smu_fan_control *fct;
160 const s32 *v;
161 const u32 *reg;
162 const char *l;
163
164 fct = kmalloc(sizeof(struct smu_fan_control), GFP_KERNEL);
165 if (fct == NULL)
166 return NULL;
167 fct->ctrl.ops = &smu_fan_ops;
168 l = of_get_property(node, "location", NULL);
169 if (l == NULL)
170 goto fail;
171
172 fct->fan_type = pwm_fan;
173 fct->ctrl.type = pwm_fan ? WF_CONTROL_PWM_FAN : WF_CONTROL_RPM_FAN;
174
175 /* We use the name & location here the same way we do for SMU sensors,
176 * see the comment in windfarm_smu_sensors.c. The locations are a bit
177 * less consistent here between the iMac and the desktop models, but
178 * that is good enough for our needs for now at least.
179 *
180 * One problem though is that Apple seem to be inconsistent with case
181 * and the kernel doesn't have strcasecmp =P
182 */
183
184 fct->ctrl.name = NULL;
185
186 /* Names used on desktop models */
187 if (!strcmp(l, "Rear Fan 0") || !strcmp(l, "Rear Fan") ||
188 !strcmp(l, "Rear fan 0") || !strcmp(l, "Rear fan") ||
189 !strcmp(l, "CPU A EXHAUST"))
190 fct->ctrl.name = "cpu-rear-fan-0";
191 else if (!strcmp(l, "Rear Fan 1") || !strcmp(l, "Rear fan 1") ||
192 !strcmp(l, "CPU B EXHAUST"))
193 fct->ctrl.name = "cpu-rear-fan-1";
194 else if (!strcmp(l, "Front Fan 0") || !strcmp(l, "Front Fan") ||
195 !strcmp(l, "Front fan 0") || !strcmp(l, "Front fan") ||
196 !strcmp(l, "CPU A INTAKE"))
197 fct->ctrl.name = "cpu-front-fan-0";
198 else if (!strcmp(l, "Front Fan 1") || !strcmp(l, "Front fan 1") ||
199 !strcmp(l, "CPU B INTAKE"))
200 fct->ctrl.name = "cpu-front-fan-1";
201 else if (!strcmp(l, "CPU A PUMP"))
202 fct->ctrl.name = "cpu-pump-0";
203 else if (!strcmp(l, "CPU B PUMP"))
204 fct->ctrl.name = "cpu-pump-1";
205 else if (!strcmp(l, "Slots Fan") || !strcmp(l, "Slots fan") ||
206 !strcmp(l, "EXPANSION SLOTS INTAKE"))
207 fct->ctrl.name = "slots-fan";
208 else if (!strcmp(l, "Drive Bay") || !strcmp(l, "Drive bay") ||
209 !strcmp(l, "DRIVE BAY A INTAKE"))
210 fct->ctrl.name = "drive-bay-fan";
211 else if (!strcmp(l, "BACKSIDE"))
212 fct->ctrl.name = "backside-fan";
213
214 /* Names used on iMac models */
215 if (!strcmp(l, "System Fan") || !strcmp(l, "System fan"))
216 fct->ctrl.name = "system-fan";
217 else if (!strcmp(l, "CPU Fan") || !strcmp(l, "CPU fan"))
218 fct->ctrl.name = "cpu-fan";
219 else if (!strcmp(l, "Hard Drive") || !strcmp(l, "Hard drive"))
220 fct->ctrl.name = "drive-bay-fan";
221 else if (!strcmp(l, "HDD Fan")) /* seen on iMac G5 iSight */
222 fct->ctrl.name = "hard-drive-fan";
223 else if (!strcmp(l, "ODD Fan")) /* same */
224 fct->ctrl.name = "optical-drive-fan";
225
226 /* Unrecognized fan, bail out */
227 if (fct->ctrl.name == NULL)
228 goto fail;
229
230 /* Get min & max values*/
231 v = of_get_property(node, "min-value", NULL);
232 if (v == NULL)
233 goto fail;
234 fct->min = *v;
235 v = of_get_property(node, "max-value", NULL);
236 if (v == NULL)
237 goto fail;
238 fct->max = *v;
239
240 /* Get "reg" value */
241 reg = of_get_property(node, "reg", NULL);
242 if (reg == NULL)
243 goto fail;
244 fct->reg = *reg;
245
246 if (wf_register_control(&fct->ctrl))
247 goto fail;
248
249 return fct;
250 fail:
251 kfree(fct);
252 return NULL;
253 }
254
255
smu_controls_init(void)256 static int __init smu_controls_init(void)
257 {
258 struct device_node *smu, *fans, *fan;
259
260 if (!smu_present())
261 return -ENODEV;
262
263 smu = of_find_node_by_type(NULL, "smu");
264 if (smu == NULL)
265 return -ENODEV;
266
267 /* Look for RPM fans */
268 for (fans = NULL; (fans = of_get_next_child(smu, fans)) != NULL;)
269 if (of_node_name_eq(fans, "rpm-fans") ||
270 of_device_is_compatible(fans, "smu-rpm-fans"))
271 break;
272 for (fan = NULL;
273 fans && (fan = of_get_next_child(fans, fan)) != NULL;) {
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 (fans = NULL; (fans = of_get_next_child(smu, fans)) != NULL;)
289 if (of_node_name_eq(fans, "pwm-fans"))
290 break;
291 for (fan = NULL;
292 fans && (fan = of_get_next_child(fans, fan)) != NULL;) {
293 struct smu_fan_control *fct;
294
295 fct = smu_fan_create(fan, 1);
296 if (fct == NULL) {
297 printk(KERN_WARNING "windfarm: Failed to create SMU "
298 "PWM fan %pOFn\n", fan);
299 continue;
300 }
301 list_add(&fct->link, &smu_fans);
302 }
303 of_node_put(fans);
304 of_node_put(smu);
305
306 return 0;
307 }
308
smu_controls_exit(void)309 static void __exit smu_controls_exit(void)
310 {
311 struct smu_fan_control *fct;
312
313 while (!list_empty(&smu_fans)) {
314 fct = list_entry(smu_fans.next, struct smu_fan_control, link);
315 list_del(&fct->link);
316 wf_unregister_control(&fct->ctrl);
317 }
318 }
319
320
321 module_init(smu_controls_init);
322 module_exit(smu_controls_exit);
323
324 MODULE_AUTHOR("Benjamin Herrenschmidt <benh@kernel.crashing.org>");
325 MODULE_DESCRIPTION("SMU control objects for PowerMacs thermal control");
326 MODULE_LICENSE("GPL");
327
328