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0f1d683f NC |
1 | /* |
2 | * pcc-cpufreq.c - Processor Clocking Control firmware cpufreq interface | |
3 | * | |
4 | * Copyright (C) 2009 Red Hat, Matthew Garrett <mjg@redhat.com> | |
5 | * Copyright (C) 2009 Hewlett-Packard Development Company, L.P. | |
6 | * Nagananda Chumbalkar <nagananda.chumbalkar@hp.com> | |
7 | * | |
8 | * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ | |
9 | * | |
10 | * This program is free software; you can redistribute it and/or modify | |
11 | * it under the terms of the GNU General Public License as published by | |
12 | * the Free Software Foundation; version 2 of the License. | |
13 | * | |
14 | * This program is distributed in the hope that it will be useful, but | |
15 | * WITHOUT ANY WARRANTY; without even the implied warranty of | |
16 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE, GOOD TITLE or NON | |
17 | * INFRINGEMENT. See the GNU General Public License for more details. | |
18 | * | |
19 | * You should have received a copy of the GNU General Public License along | |
20 | * with this program; if not, write to the Free Software Foundation, Inc., | |
21 | * 675 Mass Ave, Cambridge, MA 02139, USA. | |
22 | * | |
23 | * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ | |
24 | */ | |
25 | ||
26 | #include <linux/kernel.h> | |
27 | #include <linux/module.h> | |
28 | #include <linux/init.h> | |
29 | #include <linux/smp.h> | |
30 | #include <linux/sched.h> | |
31 | #include <linux/cpufreq.h> | |
32 | #include <linux/compiler.h> | |
5a0e3ad6 | 33 | #include <linux/slab.h> |
0f1d683f NC |
34 | |
35 | #include <linux/acpi.h> | |
36 | #include <linux/io.h> | |
37 | #include <linux/spinlock.h> | |
38 | #include <linux/uaccess.h> | |
39 | ||
40 | #include <acpi/processor.h> | |
41 | ||
904cc1e6 | 42 | #define PCC_VERSION "1.10.00" |
0f1d683f NC |
43 | #define POLL_LOOPS 300 |
44 | ||
45 | #define CMD_COMPLETE 0x1 | |
46 | #define CMD_GET_FREQ 0x0 | |
47 | #define CMD_SET_FREQ 0x1 | |
48 | ||
49 | #define BUF_SZ 4 | |
50 | ||
0f1d683f NC |
51 | struct pcc_register_resource { |
52 | u8 descriptor; | |
53 | u16 length; | |
54 | u8 space_id; | |
55 | u8 bit_width; | |
56 | u8 bit_offset; | |
57 | u8 access_size; | |
58 | u64 address; | |
59 | } __attribute__ ((packed)); | |
60 | ||
61 | struct pcc_memory_resource { | |
62 | u8 descriptor; | |
63 | u16 length; | |
64 | u8 space_id; | |
65 | u8 resource_usage; | |
66 | u8 type_specific; | |
67 | u64 granularity; | |
68 | u64 minimum; | |
69 | u64 maximum; | |
70 | u64 translation_offset; | |
71 | u64 address_length; | |
72 | } __attribute__ ((packed)); | |
73 | ||
74 | static struct cpufreq_driver pcc_cpufreq_driver; | |
75 | ||
76 | struct pcc_header { | |
77 | u32 signature; | |
78 | u16 length; | |
79 | u8 major; | |
80 | u8 minor; | |
81 | u32 features; | |
82 | u16 command; | |
83 | u16 status; | |
84 | u32 latency; | |
85 | u32 minimum_time; | |
86 | u32 maximum_time; | |
87 | u32 nominal; | |
88 | u32 throttled_frequency; | |
89 | u32 minimum_frequency; | |
90 | }; | |
91 | ||
92 | static void __iomem *pcch_virt_addr; | |
93 | static struct pcc_header __iomem *pcch_hdr; | |
94 | ||
95 | static DEFINE_SPINLOCK(pcc_lock); | |
96 | ||
97 | static struct acpi_generic_address doorbell; | |
98 | ||
99 | static u64 doorbell_preserve; | |
100 | static u64 doorbell_write; | |
101 | ||
904cc1e6 | 102 | static u8 OSC_UUID[16] = {0x9F, 0x2C, 0x9B, 0x63, 0x91, 0x70, 0x1f, 0x49, |
0f1d683f NC |
103 | 0xBB, 0x4F, 0xA5, 0x98, 0x2F, 0xA1, 0xB5, 0x46}; |
104 | ||
105 | struct pcc_cpu { | |
106 | u32 input_offset; | |
107 | u32 output_offset; | |
108 | }; | |
109 | ||
a3da3234 | 110 | static struct pcc_cpu __percpu *pcc_cpu_info; |
0f1d683f NC |
111 | |
112 | static int pcc_cpufreq_verify(struct cpufreq_policy *policy) | |
113 | { | |
114 | cpufreq_verify_within_limits(policy, policy->cpuinfo.min_freq, | |
115 | policy->cpuinfo.max_freq); | |
116 | return 0; | |
117 | } | |
118 | ||
119 | static inline void pcc_cmd(void) | |
120 | { | |
121 | u64 doorbell_value; | |
122 | int i; | |
123 | ||
124 | acpi_read(&doorbell_value, &doorbell); | |
125 | acpi_write((doorbell_value & doorbell_preserve) | doorbell_write, | |
126 | &doorbell); | |
127 | ||
128 | for (i = 0; i < POLL_LOOPS; i++) { | |
129 | if (ioread16(&pcch_hdr->status) & CMD_COMPLETE) | |
130 | break; | |
131 | } | |
132 | } | |
133 | ||
134 | static inline void pcc_clear_mapping(void) | |
135 | { | |
136 | if (pcch_virt_addr) | |
137 | iounmap(pcch_virt_addr); | |
138 | pcch_virt_addr = NULL; | |
139 | } | |
140 | ||
141 | static unsigned int pcc_get_freq(unsigned int cpu) | |
142 | { | |
143 | struct pcc_cpu *pcc_cpu_data; | |
144 | unsigned int curr_freq; | |
145 | unsigned int freq_limit; | |
146 | u16 status; | |
147 | u32 input_buffer; | |
148 | u32 output_buffer; | |
149 | ||
150 | spin_lock(&pcc_lock); | |
151 | ||
2d06d8c4 | 152 | pr_debug("get: get_freq for CPU %d\n", cpu); |
0f1d683f NC |
153 | pcc_cpu_data = per_cpu_ptr(pcc_cpu_info, cpu); |
154 | ||
155 | input_buffer = 0x1; | |
156 | iowrite32(input_buffer, | |
157 | (pcch_virt_addr + pcc_cpu_data->input_offset)); | |
158 | iowrite16(CMD_GET_FREQ, &pcch_hdr->command); | |
159 | ||
160 | pcc_cmd(); | |
161 | ||
162 | output_buffer = | |
163 | ioread32(pcch_virt_addr + pcc_cpu_data->output_offset); | |
164 | ||
165 | /* Clear the input buffer - we are done with the current command */ | |
166 | memset_io((pcch_virt_addr + pcc_cpu_data->input_offset), 0, BUF_SZ); | |
167 | ||
168 | status = ioread16(&pcch_hdr->status); | |
169 | if (status != CMD_COMPLETE) { | |
2d06d8c4 | 170 | pr_debug("get: FAILED: for CPU %d, status is %d\n", |
0f1d683f NC |
171 | cpu, status); |
172 | goto cmd_incomplete; | |
173 | } | |
174 | iowrite16(0, &pcch_hdr->status); | |
175 | curr_freq = (((ioread32(&pcch_hdr->nominal) * (output_buffer & 0xff)) | |
176 | / 100) * 1000); | |
177 | ||
2d06d8c4 DB |
178 | pr_debug("get: SUCCESS: (virtual) output_offset for cpu %d is " |
179 | "0x%p, contains a value of: 0x%x. Speed is: %d MHz\n", | |
0f1d683f NC |
180 | cpu, (pcch_virt_addr + pcc_cpu_data->output_offset), |
181 | output_buffer, curr_freq); | |
182 | ||
183 | freq_limit = (output_buffer >> 8) & 0xff; | |
184 | if (freq_limit != 0xff) { | |
2d06d8c4 | 185 | pr_debug("get: frequency for cpu %d is being temporarily" |
0f1d683f NC |
186 | " capped at %d\n", cpu, curr_freq); |
187 | } | |
188 | ||
189 | spin_unlock(&pcc_lock); | |
190 | return curr_freq; | |
191 | ||
192 | cmd_incomplete: | |
193 | iowrite16(0, &pcch_hdr->status); | |
194 | spin_unlock(&pcc_lock); | |
1f858ef2 | 195 | return 0; |
0f1d683f NC |
196 | } |
197 | ||
198 | static int pcc_cpufreq_target(struct cpufreq_policy *policy, | |
199 | unsigned int target_freq, | |
200 | unsigned int relation) | |
201 | { | |
202 | struct pcc_cpu *pcc_cpu_data; | |
203 | struct cpufreq_freqs freqs; | |
204 | u16 status; | |
205 | u32 input_buffer; | |
206 | int cpu; | |
207 | ||
208 | spin_lock(&pcc_lock); | |
209 | cpu = policy->cpu; | |
210 | pcc_cpu_data = per_cpu_ptr(pcc_cpu_info, cpu); | |
211 | ||
2d06d8c4 DB |
212 | pr_debug("target: CPU %d should go to target freq: %d " |
213 | "(virtual) input_offset is 0x%p\n", | |
0f1d683f NC |
214 | cpu, target_freq, |
215 | (pcch_virt_addr + pcc_cpu_data->input_offset)); | |
216 | ||
217 | freqs.new = target_freq; | |
218 | freqs.cpu = cpu; | |
219 | cpufreq_notify_transition(&freqs, CPUFREQ_PRECHANGE); | |
220 | ||
221 | input_buffer = 0x1 | (((target_freq * 100) | |
222 | / (ioread32(&pcch_hdr->nominal) * 1000)) << 8); | |
223 | iowrite32(input_buffer, | |
224 | (pcch_virt_addr + pcc_cpu_data->input_offset)); | |
225 | iowrite16(CMD_SET_FREQ, &pcch_hdr->command); | |
226 | ||
227 | pcc_cmd(); | |
228 | ||
229 | /* Clear the input buffer - we are done with the current command */ | |
230 | memset_io((pcch_virt_addr + pcc_cpu_data->input_offset), 0, BUF_SZ); | |
231 | ||
232 | status = ioread16(&pcch_hdr->status); | |
233 | if (status != CMD_COMPLETE) { | |
2d06d8c4 | 234 | pr_debug("target: FAILED for cpu %d, with status: 0x%x\n", |
0f1d683f NC |
235 | cpu, status); |
236 | goto cmd_incomplete; | |
237 | } | |
238 | iowrite16(0, &pcch_hdr->status); | |
239 | ||
240 | cpufreq_notify_transition(&freqs, CPUFREQ_POSTCHANGE); | |
2d06d8c4 | 241 | pr_debug("target: was SUCCESSFUL for cpu %d\n", cpu); |
0f1d683f NC |
242 | spin_unlock(&pcc_lock); |
243 | ||
244 | return 0; | |
245 | ||
246 | cmd_incomplete: | |
247 | iowrite16(0, &pcch_hdr->status); | |
248 | spin_unlock(&pcc_lock); | |
249 | return -EINVAL; | |
250 | } | |
251 | ||
252 | static int pcc_get_offset(int cpu) | |
253 | { | |
254 | acpi_status status; | |
255 | struct acpi_buffer buffer = {ACPI_ALLOCATE_BUFFER, NULL}; | |
256 | union acpi_object *pccp, *offset; | |
257 | struct pcc_cpu *pcc_cpu_data; | |
258 | struct acpi_processor *pr; | |
259 | int ret = 0; | |
260 | ||
261 | pr = per_cpu(processors, cpu); | |
262 | pcc_cpu_data = per_cpu_ptr(pcc_cpu_info, cpu); | |
263 | ||
264 | status = acpi_evaluate_object(pr->handle, "PCCP", NULL, &buffer); | |
265 | if (ACPI_FAILURE(status)) | |
266 | return -ENODEV; | |
267 | ||
268 | pccp = buffer.pointer; | |
269 | if (!pccp || pccp->type != ACPI_TYPE_PACKAGE) { | |
270 | ret = -ENODEV; | |
271 | goto out_free; | |
272 | }; | |
273 | ||
274 | offset = &(pccp->package.elements[0]); | |
275 | if (!offset || offset->type != ACPI_TYPE_INTEGER) { | |
276 | ret = -ENODEV; | |
277 | goto out_free; | |
278 | } | |
279 | ||
280 | pcc_cpu_data->input_offset = offset->integer.value; | |
281 | ||
282 | offset = &(pccp->package.elements[1]); | |
283 | if (!offset || offset->type != ACPI_TYPE_INTEGER) { | |
284 | ret = -ENODEV; | |
285 | goto out_free; | |
286 | } | |
287 | ||
288 | pcc_cpu_data->output_offset = offset->integer.value; | |
289 | ||
290 | memset_io((pcch_virt_addr + pcc_cpu_data->input_offset), 0, BUF_SZ); | |
291 | memset_io((pcch_virt_addr + pcc_cpu_data->output_offset), 0, BUF_SZ); | |
292 | ||
2d06d8c4 | 293 | pr_debug("pcc_get_offset: for CPU %d: pcc_cpu_data " |
0f1d683f NC |
294 | "input_offset: 0x%x, pcc_cpu_data output_offset: 0x%x\n", |
295 | cpu, pcc_cpu_data->input_offset, pcc_cpu_data->output_offset); | |
296 | out_free: | |
297 | kfree(buffer.pointer); | |
298 | return ret; | |
299 | } | |
300 | ||
301 | static int __init pcc_cpufreq_do_osc(acpi_handle *handle) | |
302 | { | |
303 | acpi_status status; | |
304 | struct acpi_object_list input; | |
305 | struct acpi_buffer output = {ACPI_ALLOCATE_BUFFER, NULL}; | |
306 | union acpi_object in_params[4]; | |
307 | union acpi_object *out_obj; | |
308 | u32 capabilities[2]; | |
309 | u32 errors; | |
310 | u32 supported; | |
311 | int ret = 0; | |
312 | ||
0f1d683f NC |
313 | input.count = 4; |
314 | input.pointer = in_params; | |
315 | in_params[0].type = ACPI_TYPE_BUFFER; | |
316 | in_params[0].buffer.length = 16; | |
317 | in_params[0].buffer.pointer = OSC_UUID; | |
318 | in_params[1].type = ACPI_TYPE_INTEGER; | |
319 | in_params[1].integer.value = 1; | |
320 | in_params[2].type = ACPI_TYPE_INTEGER; | |
321 | in_params[2].integer.value = 2; | |
322 | in_params[3].type = ACPI_TYPE_BUFFER; | |
323 | in_params[3].buffer.length = 8; | |
324 | in_params[3].buffer.pointer = (u8 *)&capabilities; | |
325 | ||
326 | capabilities[0] = OSC_QUERY_ENABLE; | |
327 | capabilities[1] = 0x1; | |
328 | ||
329 | status = acpi_evaluate_object(*handle, "_OSC", &input, &output); | |
330 | if (ACPI_FAILURE(status)) | |
331 | return -ENODEV; | |
332 | ||
333 | if (!output.length) | |
334 | return -ENODEV; | |
335 | ||
336 | out_obj = output.pointer; | |
337 | if (out_obj->type != ACPI_TYPE_BUFFER) { | |
338 | ret = -ENODEV; | |
339 | goto out_free; | |
340 | } | |
341 | ||
342 | errors = *((u32 *)out_obj->buffer.pointer) & ~(1 << 0); | |
343 | if (errors) { | |
344 | ret = -ENODEV; | |
345 | goto out_free; | |
346 | } | |
347 | ||
348 | supported = *((u32 *)(out_obj->buffer.pointer + 4)); | |
349 | if (!(supported & 0x1)) { | |
350 | ret = -ENODEV; | |
351 | goto out_free; | |
352 | } | |
353 | ||
354 | kfree(output.pointer); | |
355 | capabilities[0] = 0x0; | |
356 | capabilities[1] = 0x1; | |
357 | ||
358 | status = acpi_evaluate_object(*handle, "_OSC", &input, &output); | |
359 | if (ACPI_FAILURE(status)) | |
360 | return -ENODEV; | |
361 | ||
362 | if (!output.length) | |
363 | return -ENODEV; | |
364 | ||
365 | out_obj = output.pointer; | |
36829306 PE |
366 | if (out_obj->type != ACPI_TYPE_BUFFER) { |
367 | ret = -ENODEV; | |
368 | goto out_free; | |
369 | } | |
0f1d683f NC |
370 | |
371 | errors = *((u32 *)out_obj->buffer.pointer) & ~(1 << 0); | |
36829306 PE |
372 | if (errors) { |
373 | ret = -ENODEV; | |
374 | goto out_free; | |
375 | } | |
0f1d683f NC |
376 | |
377 | supported = *((u32 *)(out_obj->buffer.pointer + 4)); | |
36829306 PE |
378 | if (!(supported & 0x1)) { |
379 | ret = -ENODEV; | |
380 | goto out_free; | |
381 | } | |
0f1d683f NC |
382 | |
383 | out_free: | |
384 | kfree(output.pointer); | |
385 | return ret; | |
386 | } | |
387 | ||
388 | static int __init pcc_cpufreq_probe(void) | |
389 | { | |
390 | acpi_status status; | |
391 | struct acpi_buffer output = {ACPI_ALLOCATE_BUFFER, NULL}; | |
392 | struct pcc_memory_resource *mem_resource; | |
393 | struct pcc_register_resource *reg_resource; | |
394 | union acpi_object *out_obj, *member; | |
47f8bcf3 | 395 | acpi_handle handle, osc_handle, pcch_handle; |
0f1d683f NC |
396 | int ret = 0; |
397 | ||
398 | status = acpi_get_handle(NULL, "\\_SB", &handle); | |
399 | if (ACPI_FAILURE(status)) | |
400 | return -ENODEV; | |
401 | ||
47f8bcf3 MG |
402 | status = acpi_get_handle(handle, "PCCH", &pcch_handle); |
403 | if (ACPI_FAILURE(status)) | |
404 | return -ENODEV; | |
405 | ||
0f1d683f NC |
406 | status = acpi_get_handle(handle, "_OSC", &osc_handle); |
407 | if (ACPI_SUCCESS(status)) { | |
408 | ret = pcc_cpufreq_do_osc(&osc_handle); | |
409 | if (ret) | |
2d06d8c4 | 410 | pr_debug("probe: _OSC evaluation did not succeed\n"); |
0f1d683f NC |
411 | /* Firmware's use of _OSC is optional */ |
412 | ret = 0; | |
413 | } | |
414 | ||
415 | status = acpi_evaluate_object(handle, "PCCH", NULL, &output); | |
416 | if (ACPI_FAILURE(status)) | |
417 | return -ENODEV; | |
418 | ||
419 | out_obj = output.pointer; | |
420 | if (out_obj->type != ACPI_TYPE_PACKAGE) { | |
421 | ret = -ENODEV; | |
422 | goto out_free; | |
423 | } | |
424 | ||
425 | member = &out_obj->package.elements[0]; | |
426 | if (member->type != ACPI_TYPE_BUFFER) { | |
427 | ret = -ENODEV; | |
428 | goto out_free; | |
429 | } | |
430 | ||
431 | mem_resource = (struct pcc_memory_resource *)member->buffer.pointer; | |
432 | ||
2d06d8c4 | 433 | pr_debug("probe: mem_resource descriptor: 0x%x," |
0f1d683f NC |
434 | " length: %d, space_id: %d, resource_usage: %d," |
435 | " type_specific: %d, granularity: 0x%llx," | |
436 | " minimum: 0x%llx, maximum: 0x%llx," | |
437 | " translation_offset: 0x%llx, address_length: 0x%llx\n", | |
438 | mem_resource->descriptor, mem_resource->length, | |
439 | mem_resource->space_id, mem_resource->resource_usage, | |
440 | mem_resource->type_specific, mem_resource->granularity, | |
441 | mem_resource->minimum, mem_resource->maximum, | |
442 | mem_resource->translation_offset, | |
443 | mem_resource->address_length); | |
444 | ||
445 | if (mem_resource->space_id != ACPI_ADR_SPACE_SYSTEM_MEMORY) { | |
446 | ret = -ENODEV; | |
447 | goto out_free; | |
448 | } | |
449 | ||
450 | pcch_virt_addr = ioremap_nocache(mem_resource->minimum, | |
451 | mem_resource->address_length); | |
452 | if (pcch_virt_addr == NULL) { | |
2d06d8c4 | 453 | pr_debug("probe: could not map shared mem region\n"); |
0f1d683f NC |
454 | goto out_free; |
455 | } | |
456 | pcch_hdr = pcch_virt_addr; | |
457 | ||
2d06d8c4 DB |
458 | pr_debug("probe: PCCH header (virtual) addr: 0x%p\n", pcch_hdr); |
459 | pr_debug("probe: PCCH header is at physical address: 0x%llx," | |
0f1d683f NC |
460 | " signature: 0x%x, length: %d bytes, major: %d, minor: %d," |
461 | " supported features: 0x%x, command field: 0x%x," | |
462 | " status field: 0x%x, nominal latency: %d us\n", | |
463 | mem_resource->minimum, ioread32(&pcch_hdr->signature), | |
464 | ioread16(&pcch_hdr->length), ioread8(&pcch_hdr->major), | |
465 | ioread8(&pcch_hdr->minor), ioread32(&pcch_hdr->features), | |
466 | ioread16(&pcch_hdr->command), ioread16(&pcch_hdr->status), | |
467 | ioread32(&pcch_hdr->latency)); | |
468 | ||
2d06d8c4 | 469 | pr_debug("probe: min time between commands: %d us," |
0f1d683f NC |
470 | " max time between commands: %d us," |
471 | " nominal CPU frequency: %d MHz," | |
472 | " minimum CPU frequency: %d MHz," | |
473 | " minimum CPU frequency without throttling: %d MHz\n", | |
474 | ioread32(&pcch_hdr->minimum_time), | |
475 | ioread32(&pcch_hdr->maximum_time), | |
476 | ioread32(&pcch_hdr->nominal), | |
477 | ioread32(&pcch_hdr->throttled_frequency), | |
478 | ioread32(&pcch_hdr->minimum_frequency)); | |
479 | ||
480 | member = &out_obj->package.elements[1]; | |
481 | if (member->type != ACPI_TYPE_BUFFER) { | |
482 | ret = -ENODEV; | |
483 | goto pcch_free; | |
484 | } | |
485 | ||
486 | reg_resource = (struct pcc_register_resource *)member->buffer.pointer; | |
487 | ||
488 | doorbell.space_id = reg_resource->space_id; | |
489 | doorbell.bit_width = reg_resource->bit_width; | |
490 | doorbell.bit_offset = reg_resource->bit_offset; | |
491 | doorbell.access_width = 64; | |
492 | doorbell.address = reg_resource->address; | |
493 | ||
2d06d8c4 | 494 | pr_debug("probe: doorbell: space_id is %d, bit_width is %d, " |
0f1d683f NC |
495 | "bit_offset is %d, access_width is %d, address is 0x%llx\n", |
496 | doorbell.space_id, doorbell.bit_width, doorbell.bit_offset, | |
497 | doorbell.access_width, reg_resource->address); | |
498 | ||
499 | member = &out_obj->package.elements[2]; | |
500 | if (member->type != ACPI_TYPE_INTEGER) { | |
501 | ret = -ENODEV; | |
502 | goto pcch_free; | |
503 | } | |
504 | ||
505 | doorbell_preserve = member->integer.value; | |
506 | ||
507 | member = &out_obj->package.elements[3]; | |
508 | if (member->type != ACPI_TYPE_INTEGER) { | |
509 | ret = -ENODEV; | |
510 | goto pcch_free; | |
511 | } | |
512 | ||
513 | doorbell_write = member->integer.value; | |
514 | ||
2d06d8c4 | 515 | pr_debug("probe: doorbell_preserve: 0x%llx," |
0f1d683f NC |
516 | " doorbell_write: 0x%llx\n", |
517 | doorbell_preserve, doorbell_write); | |
518 | ||
519 | pcc_cpu_info = alloc_percpu(struct pcc_cpu); | |
520 | if (!pcc_cpu_info) { | |
521 | ret = -ENOMEM; | |
522 | goto pcch_free; | |
523 | } | |
524 | ||
525 | printk(KERN_DEBUG "pcc-cpufreq: (v%s) driver loaded with frequency" | |
526 | " limits: %d MHz, %d MHz\n", PCC_VERSION, | |
527 | ioread32(&pcch_hdr->minimum_frequency), | |
528 | ioread32(&pcch_hdr->nominal)); | |
529 | kfree(output.pointer); | |
530 | return ret; | |
531 | pcch_free: | |
532 | pcc_clear_mapping(); | |
533 | out_free: | |
534 | kfree(output.pointer); | |
535 | return ret; | |
536 | } | |
537 | ||
538 | static int pcc_cpufreq_cpu_init(struct cpufreq_policy *policy) | |
539 | { | |
540 | unsigned int cpu = policy->cpu; | |
541 | unsigned int result = 0; | |
542 | ||
543 | if (!pcch_virt_addr) { | |
544 | result = -1; | |
179ee434 | 545 | goto out; |
0f1d683f NC |
546 | } |
547 | ||
548 | result = pcc_get_offset(cpu); | |
549 | if (result) { | |
2d06d8c4 | 550 | pr_debug("init: PCCP evaluation failed\n"); |
179ee434 | 551 | goto out; |
0f1d683f NC |
552 | } |
553 | ||
554 | policy->max = policy->cpuinfo.max_freq = | |
555 | ioread32(&pcch_hdr->nominal) * 1000; | |
556 | policy->min = policy->cpuinfo.min_freq = | |
557 | ioread32(&pcch_hdr->minimum_frequency) * 1000; | |
558 | policy->cur = pcc_get_freq(cpu); | |
559 | ||
179ee434 | 560 | if (!policy->cur) { |
2d06d8c4 | 561 | pr_debug("init: Unable to get current CPU frequency\n"); |
179ee434 MG |
562 | result = -EINVAL; |
563 | goto out; | |
564 | } | |
565 | ||
2d06d8c4 | 566 | pr_debug("init: policy->max is %d, policy->min is %d\n", |
0f1d683f | 567 | policy->max, policy->min); |
179ee434 | 568 | out: |
0f1d683f NC |
569 | return result; |
570 | } | |
571 | ||
572 | static int pcc_cpufreq_cpu_exit(struct cpufreq_policy *policy) | |
573 | { | |
574 | return 0; | |
575 | } | |
576 | ||
577 | static struct cpufreq_driver pcc_cpufreq_driver = { | |
578 | .flags = CPUFREQ_CONST_LOOPS, | |
579 | .get = pcc_get_freq, | |
580 | .verify = pcc_cpufreq_verify, | |
581 | .target = pcc_cpufreq_target, | |
582 | .init = pcc_cpufreq_cpu_init, | |
583 | .exit = pcc_cpufreq_cpu_exit, | |
584 | .name = "pcc-cpufreq", | |
585 | .owner = THIS_MODULE, | |
586 | }; | |
587 | ||
588 | static int __init pcc_cpufreq_init(void) | |
589 | { | |
590 | int ret; | |
591 | ||
592 | if (acpi_disabled) | |
593 | return 0; | |
594 | ||
595 | ret = pcc_cpufreq_probe(); | |
596 | if (ret) { | |
2d06d8c4 | 597 | pr_debug("pcc_cpufreq_init: PCCH evaluation failed\n"); |
0f1d683f NC |
598 | return ret; |
599 | } | |
600 | ||
601 | ret = cpufreq_register_driver(&pcc_cpufreq_driver); | |
602 | ||
603 | return ret; | |
604 | } | |
605 | ||
606 | static void __exit pcc_cpufreq_exit(void) | |
607 | { | |
608 | cpufreq_unregister_driver(&pcc_cpufreq_driver); | |
609 | ||
610 | pcc_clear_mapping(); | |
611 | ||
612 | free_percpu(pcc_cpu_info); | |
613 | } | |
614 | ||
615 | MODULE_AUTHOR("Matthew Garrett, Naga Chumbalkar"); | |
616 | MODULE_VERSION(PCC_VERSION); | |
617 | MODULE_DESCRIPTION("Processor Clocking Control interface driver"); | |
618 | MODULE_LICENSE("GPL"); | |
619 | ||
620 | late_initcall(pcc_cpufreq_init); | |
621 | module_exit(pcc_cpufreq_exit); |