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10#include <linux/cpufeature.h>
11#include <linux/cpuhotplug.h>
12#include <linux/fs.h>
13#include <linux/hashtable.h>
14#include <linux/miscdevice.h>
15#include <linux/module.h>
16#include <linux/pci.h>
17#include <linux/sched/signal.h>
18#include <linux/slab.h>
19#include <linux/uaccess.h>
20#include <uapi/linux/isst_if.h>
21
22#include "isst_if_common.h"
23
24#define MSR_THREAD_ID_INFO 0x53
25#define MSR_CPU_BUS_NUMBER 0x128
26
27static struct isst_if_cmd_cb punit_callbacks[ISST_IF_DEV_MAX];
28
29static int punit_msr_white_list[] = {
30 MSR_TURBO_RATIO_LIMIT,
31 MSR_CONFIG_TDP_CONTROL,
32 MSR_TURBO_RATIO_LIMIT1,
33 MSR_TURBO_RATIO_LIMIT2,
34};
35
36struct isst_valid_cmd_ranges {
37 u16 cmd;
38 u16 sub_cmd_beg;
39 u16 sub_cmd_end;
40};
41
42struct isst_cmd_set_req_type {
43 u16 cmd;
44 u16 sub_cmd;
45 u16 param;
46};
47
48static const struct isst_valid_cmd_ranges isst_valid_cmds[] = {
49 {0xD0, 0x00, 0x03},
50 {0x7F, 0x00, 0x0B},
51 {0x7F, 0x10, 0x12},
52 {0x7F, 0x20, 0x23},
53 {0x94, 0x03, 0x03},
54 {0x95, 0x03, 0x03},
55};
56
57static const struct isst_cmd_set_req_type isst_cmd_set_reqs[] = {
58 {0xD0, 0x00, 0x08},
59 {0xD0, 0x01, 0x08},
60 {0xD0, 0x02, 0x08},
61 {0xD0, 0x03, 0x08},
62 {0x7F, 0x02, 0x00},
63 {0x7F, 0x08, 0x00},
64 {0x95, 0x03, 0x03},
65};
66
67struct isst_cmd {
68 struct hlist_node hnode;
69 u64 data;
70 u32 cmd;
71 int cpu;
72 int mbox_cmd_type;
73 u32 param;
74};
75
76static DECLARE_HASHTABLE(isst_hash, 8);
77static DEFINE_MUTEX(isst_hash_lock);
78
79static int isst_store_new_cmd(int cmd, u32 cpu, int mbox_cmd_type, u32 param,
80 u32 data)
81{
82 struct isst_cmd *sst_cmd;
83
84 sst_cmd = kmalloc(sizeof(*sst_cmd), GFP_KERNEL);
85 if (!sst_cmd)
86 return -ENOMEM;
87
88 sst_cmd->cpu = cpu;
89 sst_cmd->cmd = cmd;
90 sst_cmd->mbox_cmd_type = mbox_cmd_type;
91 sst_cmd->param = param;
92 sst_cmd->data = data;
93
94 hash_add(isst_hash, &sst_cmd->hnode, sst_cmd->cmd);
95
96 return 0;
97}
98
99static void isst_delete_hash(void)
100{
101 struct isst_cmd *sst_cmd;
102 struct hlist_node *tmp;
103 int i;
104
105 hash_for_each_safe(isst_hash, i, tmp, sst_cmd, hnode) {
106 hash_del(&sst_cmd->hnode);
107 kfree(sst_cmd);
108 }
109}
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125
126int isst_store_cmd(int cmd, int sub_cmd, u32 cpu, int mbox_cmd_type,
127 u32 param, u64 data)
128{
129 struct isst_cmd *sst_cmd;
130 int full_cmd, ret;
131
132 full_cmd = (cmd & GENMASK_ULL(15, 0)) << 16;
133 full_cmd |= (sub_cmd & GENMASK_ULL(15, 0));
134 mutex_lock(&isst_hash_lock);
135 hash_for_each_possible(isst_hash, sst_cmd, hnode, full_cmd) {
136 if (sst_cmd->cmd == full_cmd && sst_cmd->cpu == cpu &&
137 sst_cmd->mbox_cmd_type == mbox_cmd_type) {
138 sst_cmd->param = param;
139 sst_cmd->data = data;
140 mutex_unlock(&isst_hash_lock);
141 return 0;
142 }
143 }
144
145 ret = isst_store_new_cmd(full_cmd, cpu, mbox_cmd_type, param, data);
146 mutex_unlock(&isst_hash_lock);
147
148 return ret;
149}
150EXPORT_SYMBOL_GPL(isst_store_cmd);
151
152static void isst_mbox_resume_command(struct isst_if_cmd_cb *cb,
153 struct isst_cmd *sst_cmd)
154{
155 struct isst_if_mbox_cmd mbox_cmd;
156 int wr_only;
157
158 mbox_cmd.command = (sst_cmd->cmd & GENMASK_ULL(31, 16)) >> 16;
159 mbox_cmd.sub_command = sst_cmd->cmd & GENMASK_ULL(15, 0);
160 mbox_cmd.parameter = sst_cmd->param;
161 mbox_cmd.req_data = sst_cmd->data;
162 mbox_cmd.logical_cpu = sst_cmd->cpu;
163 (cb->cmd_callback)((u8 *)&mbox_cmd, &wr_only, 1);
164}
165
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171
172
173void isst_resume_common(void)
174{
175 struct isst_cmd *sst_cmd;
176 int i;
177
178 hash_for_each(isst_hash, i, sst_cmd, hnode) {
179 struct isst_if_cmd_cb *cb;
180
181 if (sst_cmd->mbox_cmd_type) {
182 cb = &punit_callbacks[ISST_IF_DEV_MBOX];
183 if (cb->registered)
184 isst_mbox_resume_command(cb, sst_cmd);
185 } else {
186 wrmsrl_safe_on_cpu(sst_cmd->cpu, sst_cmd->cmd,
187 sst_cmd->data);
188 }
189 }
190}
191EXPORT_SYMBOL_GPL(isst_resume_common);
192
193static void isst_restore_msr_local(int cpu)
194{
195 struct isst_cmd *sst_cmd;
196 int i;
197
198 mutex_lock(&isst_hash_lock);
199 for (i = 0; i < ARRAY_SIZE(punit_msr_white_list); ++i) {
200 if (!punit_msr_white_list[i])
201 break;
202
203 hash_for_each_possible(isst_hash, sst_cmd, hnode,
204 punit_msr_white_list[i]) {
205 if (!sst_cmd->mbox_cmd_type && sst_cmd->cpu == cpu)
206 wrmsrl_safe(sst_cmd->cmd, sst_cmd->data);
207 }
208 }
209 mutex_unlock(&isst_hash_lock);
210}
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220
221bool isst_if_mbox_cmd_invalid(struct isst_if_mbox_cmd *cmd)
222{
223 int i;
224
225 if (cmd->logical_cpu >= nr_cpu_ids)
226 return true;
227
228 for (i = 0; i < ARRAY_SIZE(isst_valid_cmds); ++i) {
229 if (cmd->command == isst_valid_cmds[i].cmd &&
230 (cmd->sub_command >= isst_valid_cmds[i].sub_cmd_beg &&
231 cmd->sub_command <= isst_valid_cmds[i].sub_cmd_end)) {
232 return false;
233 }
234 }
235
236 return true;
237}
238EXPORT_SYMBOL_GPL(isst_if_mbox_cmd_invalid);
239
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248bool isst_if_mbox_cmd_set_req(struct isst_if_mbox_cmd *cmd)
249{
250 int i;
251
252 for (i = 0; i < ARRAY_SIZE(isst_cmd_set_reqs); ++i) {
253 if (cmd->command == isst_cmd_set_reqs[i].cmd &&
254 cmd->sub_command == isst_cmd_set_reqs[i].sub_cmd &&
255 cmd->parameter == isst_cmd_set_reqs[i].param) {
256 return true;
257 }
258 }
259
260 return false;
261}
262EXPORT_SYMBOL_GPL(isst_if_mbox_cmd_set_req);
263
264static int isst_if_get_platform_info(void __user *argp)
265{
266 struct isst_if_platform_info info;
267
268 info.api_version = ISST_IF_API_VERSION,
269 info.driver_version = ISST_IF_DRIVER_VERSION,
270 info.max_cmds_per_ioctl = ISST_IF_CMD_LIMIT,
271 info.mbox_supported = punit_callbacks[ISST_IF_DEV_MBOX].registered;
272 info.mmio_supported = punit_callbacks[ISST_IF_DEV_MMIO].registered;
273
274 if (copy_to_user(argp, &info, sizeof(info)))
275 return -EFAULT;
276
277 return 0;
278}
279
280
281struct isst_if_cpu_info {
282
283 int bus_info[2];
284 int punit_cpu_id;
285};
286
287static struct isst_if_cpu_info *isst_cpu_info;
288
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300
301struct pci_dev *isst_if_get_pci_dev(int cpu, int bus_no, int dev, int fn)
302{
303 int bus_number;
304
305 if (bus_no < 0 || bus_no > 1 || cpu < 0 || cpu >= nr_cpu_ids ||
306 cpu >= num_possible_cpus())
307 return NULL;
308
309 bus_number = isst_cpu_info[cpu].bus_info[bus_no];
310 if (bus_number < 0)
311 return NULL;
312
313 return pci_get_domain_bus_and_slot(0, bus_number, PCI_DEVFN(dev, fn));
314}
315EXPORT_SYMBOL_GPL(isst_if_get_pci_dev);
316
317static int isst_if_cpu_online(unsigned int cpu)
318{
319 u64 data;
320 int ret;
321
322 ret = rdmsrl_safe(MSR_CPU_BUS_NUMBER, &data);
323 if (ret) {
324
325 isst_cpu_info[cpu].bus_info[0] = -1;
326 isst_cpu_info[cpu].bus_info[1] = -1;
327 } else {
328 isst_cpu_info[cpu].bus_info[0] = data & 0xff;
329 isst_cpu_info[cpu].bus_info[1] = (data >> 8) & 0xff;
330 }
331
332 ret = rdmsrl_safe(MSR_THREAD_ID_INFO, &data);
333 if (ret) {
334 isst_cpu_info[cpu].punit_cpu_id = -1;
335 return ret;
336 }
337 isst_cpu_info[cpu].punit_cpu_id = data;
338
339 isst_restore_msr_local(cpu);
340
341 return 0;
342}
343
344static int isst_if_online_id;
345
346static int isst_if_cpu_info_init(void)
347{
348 int ret;
349
350 isst_cpu_info = kcalloc(num_possible_cpus(),
351 sizeof(*isst_cpu_info),
352 GFP_KERNEL);
353 if (!isst_cpu_info)
354 return -ENOMEM;
355
356 ret = cpuhp_setup_state(CPUHP_AP_ONLINE_DYN,
357 "platform/x86/isst-if:online",
358 isst_if_cpu_online, NULL);
359 if (ret < 0) {
360 kfree(isst_cpu_info);
361 return ret;
362 }
363
364 isst_if_online_id = ret;
365
366 return 0;
367}
368
369static void isst_if_cpu_info_exit(void)
370{
371 cpuhp_remove_state(isst_if_online_id);
372 kfree(isst_cpu_info);
373};
374
375static long isst_if_proc_phyid_req(u8 *cmd_ptr, int *write_only, int resume)
376{
377 struct isst_if_cpu_map *cpu_map;
378
379 cpu_map = (struct isst_if_cpu_map *)cmd_ptr;
380 if (cpu_map->logical_cpu >= nr_cpu_ids ||
381 cpu_map->logical_cpu >= num_possible_cpus())
382 return -EINVAL;
383
384 *write_only = 0;
385 cpu_map->physical_cpu = isst_cpu_info[cpu_map->logical_cpu].punit_cpu_id;
386
387 return 0;
388}
389
390static bool match_punit_msr_white_list(int msr)
391{
392 int i;
393
394 for (i = 0; i < ARRAY_SIZE(punit_msr_white_list); ++i) {
395 if (punit_msr_white_list[i] == msr)
396 return true;
397 }
398
399 return false;
400}
401
402static long isst_if_msr_cmd_req(u8 *cmd_ptr, int *write_only, int resume)
403{
404 struct isst_if_msr_cmd *msr_cmd;
405 int ret;
406
407 msr_cmd = (struct isst_if_msr_cmd *)cmd_ptr;
408
409 if (!match_punit_msr_white_list(msr_cmd->msr))
410 return -EINVAL;
411
412 if (msr_cmd->logical_cpu >= nr_cpu_ids)
413 return -EINVAL;
414
415 if (msr_cmd->read_write) {
416 if (!capable(CAP_SYS_ADMIN))
417 return -EPERM;
418
419 ret = wrmsrl_safe_on_cpu(msr_cmd->logical_cpu,
420 msr_cmd->msr,
421 msr_cmd->data);
422 *write_only = 1;
423 if (!ret && !resume)
424 ret = isst_store_cmd(0, msr_cmd->msr,
425 msr_cmd->logical_cpu,
426 0, 0, msr_cmd->data);
427 } else {
428 u64 data;
429
430 ret = rdmsrl_safe_on_cpu(msr_cmd->logical_cpu,
431 msr_cmd->msr, &data);
432 if (!ret) {
433 msr_cmd->data = data;
434 *write_only = 0;
435 }
436 }
437
438
439 return ret;
440}
441
442static long isst_if_exec_multi_cmd(void __user *argp, struct isst_if_cmd_cb *cb)
443{
444 unsigned char __user *ptr;
445 u32 cmd_count;
446 u8 *cmd_ptr;
447 long ret;
448 int i;
449
450
451 if (copy_from_user(&cmd_count, argp, sizeof(cmd_count)))
452 return -EFAULT;
453
454 if (!cmd_count || cmd_count > ISST_IF_CMD_LIMIT)
455 return -EINVAL;
456
457 cmd_ptr = kmalloc(cb->cmd_size, GFP_KERNEL);
458 if (!cmd_ptr)
459 return -ENOMEM;
460
461
462 ptr = argp + cb->offset;
463
464 for (i = 0; i < cmd_count; ++i) {
465 int wr_only;
466
467 if (signal_pending(current)) {
468 ret = -EINTR;
469 break;
470 }
471
472 if (copy_from_user(cmd_ptr, ptr, cb->cmd_size)) {
473 ret = -EFAULT;
474 break;
475 }
476
477 ret = cb->cmd_callback(cmd_ptr, &wr_only, 0);
478 if (ret)
479 break;
480
481 if (!wr_only && copy_to_user(ptr, cmd_ptr, cb->cmd_size)) {
482 ret = -EFAULT;
483 break;
484 }
485
486 ptr += cb->cmd_size;
487 }
488
489 kfree(cmd_ptr);
490
491 return i ? i : ret;
492}
493
494static long isst_if_def_ioctl(struct file *file, unsigned int cmd,
495 unsigned long arg)
496{
497 void __user *argp = (void __user *)arg;
498 struct isst_if_cmd_cb cmd_cb;
499 struct isst_if_cmd_cb *cb;
500 long ret = -ENOTTY;
501
502 switch (cmd) {
503 case ISST_IF_GET_PLATFORM_INFO:
504 ret = isst_if_get_platform_info(argp);
505 break;
506 case ISST_IF_GET_PHY_ID:
507 cmd_cb.cmd_size = sizeof(struct isst_if_cpu_map);
508 cmd_cb.offset = offsetof(struct isst_if_cpu_maps, cpu_map);
509 cmd_cb.cmd_callback = isst_if_proc_phyid_req;
510 ret = isst_if_exec_multi_cmd(argp, &cmd_cb);
511 break;
512 case ISST_IF_IO_CMD:
513 cb = &punit_callbacks[ISST_IF_DEV_MMIO];
514 if (cb->registered)
515 ret = isst_if_exec_multi_cmd(argp, cb);
516 break;
517 case ISST_IF_MBOX_COMMAND:
518 cb = &punit_callbacks[ISST_IF_DEV_MBOX];
519 if (cb->registered)
520 ret = isst_if_exec_multi_cmd(argp, cb);
521 break;
522 case ISST_IF_MSR_COMMAND:
523 cmd_cb.cmd_size = sizeof(struct isst_if_msr_cmd);
524 cmd_cb.offset = offsetof(struct isst_if_msr_cmds, msr_cmd);
525 cmd_cb.cmd_callback = isst_if_msr_cmd_req;
526 ret = isst_if_exec_multi_cmd(argp, &cmd_cb);
527 break;
528 default:
529 break;
530 }
531
532 return ret;
533}
534
535static DEFINE_MUTEX(punit_misc_dev_lock);
536static int misc_usage_count;
537static int misc_device_ret;
538static int misc_device_open;
539
540static int isst_if_open(struct inode *inode, struct file *file)
541{
542 int i, ret = 0;
543
544
545 mutex_lock(&punit_misc_dev_lock);
546 for (i = 0; i < ISST_IF_DEV_MAX; ++i) {
547 struct isst_if_cmd_cb *cb = &punit_callbacks[i];
548
549 if (cb->registered && !try_module_get(cb->owner)) {
550 ret = -ENODEV;
551 break;
552 }
553 }
554 if (ret) {
555 int j;
556
557 for (j = 0; j < i; ++j) {
558 struct isst_if_cmd_cb *cb;
559
560 cb = &punit_callbacks[j];
561 if (cb->registered)
562 module_put(cb->owner);
563 }
564 } else {
565 misc_device_open++;
566 }
567 mutex_unlock(&punit_misc_dev_lock);
568
569 return ret;
570}
571
572static int isst_if_relase(struct inode *inode, struct file *f)
573{
574 int i;
575
576 mutex_lock(&punit_misc_dev_lock);
577 misc_device_open--;
578 for (i = 0; i < ISST_IF_DEV_MAX; ++i) {
579 struct isst_if_cmd_cb *cb = &punit_callbacks[i];
580
581 if (cb->registered)
582 module_put(cb->owner);
583 }
584 mutex_unlock(&punit_misc_dev_lock);
585
586 return 0;
587}
588
589static const struct file_operations isst_if_char_driver_ops = {
590 .open = isst_if_open,
591 .unlocked_ioctl = isst_if_def_ioctl,
592 .release = isst_if_relase,
593};
594
595static struct miscdevice isst_if_char_driver = {
596 .minor = MISC_DYNAMIC_MINOR,
597 .name = "isst_interface",
598 .fops = &isst_if_char_driver_ops,
599};
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616int isst_if_cdev_register(int device_type, struct isst_if_cmd_cb *cb)
617{
618 if (misc_device_ret)
619 return misc_device_ret;
620
621 if (device_type >= ISST_IF_DEV_MAX)
622 return -EINVAL;
623
624 mutex_lock(&punit_misc_dev_lock);
625 if (misc_device_open) {
626 mutex_unlock(&punit_misc_dev_lock);
627 return -EAGAIN;
628 }
629 if (!misc_usage_count) {
630 int ret;
631
632 misc_device_ret = misc_register(&isst_if_char_driver);
633 if (misc_device_ret)
634 goto unlock_exit;
635
636 ret = isst_if_cpu_info_init();
637 if (ret) {
638 misc_deregister(&isst_if_char_driver);
639 misc_device_ret = ret;
640 goto unlock_exit;
641 }
642 }
643 memcpy(&punit_callbacks[device_type], cb, sizeof(*cb));
644 punit_callbacks[device_type].registered = 1;
645 misc_usage_count++;
646unlock_exit:
647 mutex_unlock(&punit_misc_dev_lock);
648
649 return misc_device_ret;
650}
651EXPORT_SYMBOL_GPL(isst_if_cdev_register);
652
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661
662void isst_if_cdev_unregister(int device_type)
663{
664 mutex_lock(&punit_misc_dev_lock);
665 misc_usage_count--;
666 punit_callbacks[device_type].registered = 0;
667 if (device_type == ISST_IF_DEV_MBOX)
668 isst_delete_hash();
669 if (!misc_usage_count && !misc_device_ret) {
670 misc_deregister(&isst_if_char_driver);
671 isst_if_cpu_info_exit();
672 }
673 mutex_unlock(&punit_misc_dev_lock);
674}
675EXPORT_SYMBOL_GPL(isst_if_cdev_unregister);
676
677MODULE_LICENSE("GPL v2");
678