Merge tag 'dma-mapping-4.17-2' of git://git.infradead.org/users/hch/dma-mapping
[muen/linux.git] / drivers / xen / xen-acpi-processor.c
1 /*
2  * Copyright 2012 by Oracle Inc
3  * Author: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
4  *
5  * This code borrows ideas from https://lkml.org/lkml/2011/11/30/249
6  * so many thanks go to Kevin Tian <kevin.tian@intel.com>
7  * and Yu Ke <ke.yu@intel.com>.
8  *
9  * This program is free software; you can redistribute it and/or modify it
10  * under the terms and conditions of the GNU General Public License,
11  * version 2, as published by the Free Software Foundation.
12  *
13  * This program is distributed in the hope it will be useful, but WITHOUT
14  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
15  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
16  * more details.
17  *
18  */
19
20 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
21
22 #include <linux/cpumask.h>
23 #include <linux/cpufreq.h>
24 #include <linux/freezer.h>
25 #include <linux/kernel.h>
26 #include <linux/kthread.h>
27 #include <linux/init.h>
28 #include <linux/module.h>
29 #include <linux/types.h>
30 #include <linux/syscore_ops.h>
31 #include <linux/acpi.h>
32 #include <acpi/processor.h>
33 #include <xen/xen.h>
34 #include <xen/interface/platform.h>
35 #include <asm/xen/hypercall.h>
36
37 static int no_hypercall;
38 MODULE_PARM_DESC(off, "Inhibit the hypercall.");
39 module_param_named(off, no_hypercall, int, 0400);
40
41 /*
42  * Note: Do not convert the acpi_id* below to cpumask_var_t or use cpumask_bit
43  * - as those shrink to nr_cpu_bits (which is dependent on possible_cpu), which
44  * can be less than what we want to put in. Instead use the 'nr_acpi_bits'
45  * which is dynamically computed based on the MADT or x2APIC table.
46  */
47 static unsigned int nr_acpi_bits;
48 /* Mutex to protect the acpi_ids_done - for CPU hotplug use. */
49 static DEFINE_MUTEX(acpi_ids_mutex);
50 /* Which ACPI ID we have processed from 'struct acpi_processor'. */
51 static unsigned long *acpi_ids_done;
52 /* Which ACPI ID exist in the SSDT/DSDT processor definitions. */
53 static unsigned long *acpi_id_present;
54 /* And if there is an _CST definition (or a PBLK) for the ACPI IDs */
55 static unsigned long *acpi_id_cst_present;
56
57 static int push_cxx_to_hypervisor(struct acpi_processor *_pr)
58 {
59         struct xen_platform_op op = {
60                 .cmd                    = XENPF_set_processor_pminfo,
61                 .interface_version      = XENPF_INTERFACE_VERSION,
62                 .u.set_pminfo.id        = _pr->acpi_id,
63                 .u.set_pminfo.type      = XEN_PM_CX,
64         };
65         struct xen_processor_cx *dst_cx, *dst_cx_states = NULL;
66         struct acpi_processor_cx *cx;
67         unsigned int i, ok;
68         int ret = 0;
69
70         dst_cx_states = kcalloc(_pr->power.count,
71                                 sizeof(struct xen_processor_cx), GFP_KERNEL);
72         if (!dst_cx_states)
73                 return -ENOMEM;
74
75         for (ok = 0, i = 1; i <= _pr->power.count; i++) {
76                 cx = &_pr->power.states[i];
77                 if (!cx->valid)
78                         continue;
79
80                 dst_cx = &(dst_cx_states[ok++]);
81
82                 dst_cx->reg.space_id = ACPI_ADR_SPACE_SYSTEM_IO;
83                 if (cx->entry_method == ACPI_CSTATE_SYSTEMIO) {
84                         dst_cx->reg.bit_width = 8;
85                         dst_cx->reg.bit_offset = 0;
86                         dst_cx->reg.access_size = 1;
87                 } else {
88                         dst_cx->reg.space_id = ACPI_ADR_SPACE_FIXED_HARDWARE;
89                         if (cx->entry_method == ACPI_CSTATE_FFH) {
90                                 /* NATIVE_CSTATE_BEYOND_HALT */
91                                 dst_cx->reg.bit_offset = 2;
92                                 dst_cx->reg.bit_width = 1; /* VENDOR_INTEL */
93                         }
94                         dst_cx->reg.access_size = 0;
95                 }
96                 dst_cx->reg.address = cx->address;
97
98                 dst_cx->type = cx->type;
99                 dst_cx->latency = cx->latency;
100
101                 dst_cx->dpcnt = 0;
102                 set_xen_guest_handle(dst_cx->dp, NULL);
103         }
104         if (!ok) {
105                 pr_debug("No _Cx for ACPI CPU %u\n", _pr->acpi_id);
106                 kfree(dst_cx_states);
107                 return -EINVAL;
108         }
109         op.u.set_pminfo.power.count = ok;
110         op.u.set_pminfo.power.flags.bm_control = _pr->flags.bm_control;
111         op.u.set_pminfo.power.flags.bm_check = _pr->flags.bm_check;
112         op.u.set_pminfo.power.flags.has_cst = _pr->flags.has_cst;
113         op.u.set_pminfo.power.flags.power_setup_done =
114                 _pr->flags.power_setup_done;
115
116         set_xen_guest_handle(op.u.set_pminfo.power.states, dst_cx_states);
117
118         if (!no_hypercall)
119                 ret = HYPERVISOR_platform_op(&op);
120
121         if (!ret) {
122                 pr_debug("ACPI CPU%u - C-states uploaded.\n", _pr->acpi_id);
123                 for (i = 1; i <= _pr->power.count; i++) {
124                         cx = &_pr->power.states[i];
125                         if (!cx->valid)
126                                 continue;
127                         pr_debug("     C%d: %s %d uS\n",
128                                  cx->type, cx->desc, (u32)cx->latency);
129                 }
130         } else if ((ret != -EINVAL) && (ret != -ENOSYS))
131                 /* EINVAL means the ACPI ID is incorrect - meaning the ACPI
132                  * table is referencing a non-existing CPU - which can happen
133                  * with broken ACPI tables. */
134                 pr_err("(CX): Hypervisor error (%d) for ACPI CPU%u\n",
135                        ret, _pr->acpi_id);
136
137         kfree(dst_cx_states);
138
139         return ret;
140 }
141 static struct xen_processor_px *
142 xen_copy_pss_data(struct acpi_processor *_pr,
143                   struct xen_processor_performance *dst_perf)
144 {
145         struct xen_processor_px *dst_states = NULL;
146         unsigned int i;
147
148         BUILD_BUG_ON(sizeof(struct xen_processor_px) !=
149                      sizeof(struct acpi_processor_px));
150
151         dst_states = kcalloc(_pr->performance->state_count,
152                              sizeof(struct xen_processor_px), GFP_KERNEL);
153         if (!dst_states)
154                 return ERR_PTR(-ENOMEM);
155
156         dst_perf->state_count = _pr->performance->state_count;
157         for (i = 0; i < _pr->performance->state_count; i++) {
158                 /* Fortunatly for us, they are both the same size */
159                 memcpy(&(dst_states[i]), &(_pr->performance->states[i]),
160                        sizeof(struct acpi_processor_px));
161         }
162         return dst_states;
163 }
164 static int xen_copy_psd_data(struct acpi_processor *_pr,
165                              struct xen_processor_performance *dst)
166 {
167         struct acpi_psd_package *pdomain;
168
169         BUILD_BUG_ON(sizeof(struct xen_psd_package) !=
170                      sizeof(struct acpi_psd_package));
171
172         /* This information is enumerated only if acpi_processor_preregister_performance
173          * has been called.
174          */
175         dst->shared_type = _pr->performance->shared_type;
176
177         pdomain = &(_pr->performance->domain_info);
178
179         /* 'acpi_processor_preregister_performance' does not parse if the
180          * num_processors <= 1, but Xen still requires it. Do it manually here.
181          */
182         if (pdomain->num_processors <= 1) {
183                 if (pdomain->coord_type == DOMAIN_COORD_TYPE_SW_ALL)
184                         dst->shared_type = CPUFREQ_SHARED_TYPE_ALL;
185                 else if (pdomain->coord_type == DOMAIN_COORD_TYPE_HW_ALL)
186                         dst->shared_type = CPUFREQ_SHARED_TYPE_HW;
187                 else if (pdomain->coord_type == DOMAIN_COORD_TYPE_SW_ANY)
188                         dst->shared_type = CPUFREQ_SHARED_TYPE_ANY;
189
190         }
191         memcpy(&(dst->domain_info), pdomain, sizeof(struct acpi_psd_package));
192         return 0;
193 }
194 static int xen_copy_pct_data(struct acpi_pct_register *pct,
195                              struct xen_pct_register *dst_pct)
196 {
197         /* It would be nice if you could just do 'memcpy(pct, dst_pct') but
198          * sadly the Xen structure did not have the proper padding so the
199          * descriptor field takes two (dst_pct) bytes instead of one (pct).
200          */
201         dst_pct->descriptor = pct->descriptor;
202         dst_pct->length = pct->length;
203         dst_pct->space_id = pct->space_id;
204         dst_pct->bit_width = pct->bit_width;
205         dst_pct->bit_offset = pct->bit_offset;
206         dst_pct->reserved = pct->reserved;
207         dst_pct->address = pct->address;
208         return 0;
209 }
210 static int push_pxx_to_hypervisor(struct acpi_processor *_pr)
211 {
212         int ret = 0;
213         struct xen_platform_op op = {
214                 .cmd                    = XENPF_set_processor_pminfo,
215                 .interface_version      = XENPF_INTERFACE_VERSION,
216                 .u.set_pminfo.id        = _pr->acpi_id,
217                 .u.set_pminfo.type      = XEN_PM_PX,
218         };
219         struct xen_processor_performance *dst_perf;
220         struct xen_processor_px *dst_states = NULL;
221
222         dst_perf = &op.u.set_pminfo.perf;
223
224         dst_perf->platform_limit = _pr->performance_platform_limit;
225         dst_perf->flags |= XEN_PX_PPC;
226         xen_copy_pct_data(&(_pr->performance->control_register),
227                           &dst_perf->control_register);
228         xen_copy_pct_data(&(_pr->performance->status_register),
229                           &dst_perf->status_register);
230         dst_perf->flags |= XEN_PX_PCT;
231         dst_states = xen_copy_pss_data(_pr, dst_perf);
232         if (!IS_ERR_OR_NULL(dst_states)) {
233                 set_xen_guest_handle(dst_perf->states, dst_states);
234                 dst_perf->flags |= XEN_PX_PSS;
235         }
236         if (!xen_copy_psd_data(_pr, dst_perf))
237                 dst_perf->flags |= XEN_PX_PSD;
238
239         if (dst_perf->flags != (XEN_PX_PSD | XEN_PX_PSS | XEN_PX_PCT | XEN_PX_PPC)) {
240                 pr_warn("ACPI CPU%u missing some P-state data (%x), skipping\n",
241                         _pr->acpi_id, dst_perf->flags);
242                 ret = -ENODEV;
243                 goto err_free;
244         }
245
246         if (!no_hypercall)
247                 ret = HYPERVISOR_platform_op(&op);
248
249         if (!ret) {
250                 struct acpi_processor_performance *perf;
251                 unsigned int i;
252
253                 perf = _pr->performance;
254                 pr_debug("ACPI CPU%u - P-states uploaded.\n", _pr->acpi_id);
255                 for (i = 0; i < perf->state_count; i++) {
256                         pr_debug("     %cP%d: %d MHz, %d mW, %d uS\n",
257                         (i == perf->state ? '*' : ' '), i,
258                         (u32) perf->states[i].core_frequency,
259                         (u32) perf->states[i].power,
260                         (u32) perf->states[i].transition_latency);
261                 }
262         } else if ((ret != -EINVAL) && (ret != -ENOSYS))
263                 /* EINVAL means the ACPI ID is incorrect - meaning the ACPI
264                  * table is referencing a non-existing CPU - which can happen
265                  * with broken ACPI tables. */
266                 pr_warn("(_PXX): Hypervisor error (%d) for ACPI CPU%u\n",
267                         ret, _pr->acpi_id);
268 err_free:
269         if (!IS_ERR_OR_NULL(dst_states))
270                 kfree(dst_states);
271
272         return ret;
273 }
274 static int upload_pm_data(struct acpi_processor *_pr)
275 {
276         int err = 0;
277
278         mutex_lock(&acpi_ids_mutex);
279         if (__test_and_set_bit(_pr->acpi_id, acpi_ids_done)) {
280                 mutex_unlock(&acpi_ids_mutex);
281                 return -EBUSY;
282         }
283         if (_pr->flags.power)
284                 err = push_cxx_to_hypervisor(_pr);
285
286         if (_pr->performance && _pr->performance->states)
287                 err |= push_pxx_to_hypervisor(_pr);
288
289         mutex_unlock(&acpi_ids_mutex);
290         return err;
291 }
292 static unsigned int __init get_max_acpi_id(void)
293 {
294         struct xenpf_pcpuinfo *info;
295         struct xen_platform_op op = {
296                 .cmd = XENPF_get_cpuinfo,
297                 .interface_version = XENPF_INTERFACE_VERSION,
298         };
299         int ret = 0;
300         unsigned int i, last_cpu, max_acpi_id = 0;
301
302         info = &op.u.pcpu_info;
303         info->xen_cpuid = 0;
304
305         ret = HYPERVISOR_platform_op(&op);
306         if (ret)
307                 return NR_CPUS;
308
309         /* The max_present is the same irregardless of the xen_cpuid */
310         last_cpu = op.u.pcpu_info.max_present;
311         for (i = 0; i <= last_cpu; i++) {
312                 info->xen_cpuid = i;
313                 ret = HYPERVISOR_platform_op(&op);
314                 if (ret)
315                         continue;
316                 max_acpi_id = max(info->acpi_id, max_acpi_id);
317         }
318         max_acpi_id *= 2; /* Slack for CPU hotplug support. */
319         pr_debug("Max ACPI ID: %u\n", max_acpi_id);
320         return max_acpi_id;
321 }
322 /*
323  * The read_acpi_id and check_acpi_ids are there to support the Xen
324  * oddity of virtual CPUs != physical CPUs in the initial domain.
325  * The user can supply 'xen_max_vcpus=X' on the Xen hypervisor line
326  * which will band the amount of CPUs the initial domain can see.
327  * In general that is OK, except it plays havoc with any of the
328  * for_each_[present|online]_cpu macros which are banded to the virtual
329  * CPU amount.
330  */
331 static acpi_status
332 read_acpi_id(acpi_handle handle, u32 lvl, void *context, void **rv)
333 {
334         u32 acpi_id;
335         acpi_status status;
336         acpi_object_type acpi_type;
337         unsigned long long tmp;
338         union acpi_object object = { 0 };
339         struct acpi_buffer buffer = { sizeof(union acpi_object), &object };
340         acpi_io_address pblk = 0;
341
342         status = acpi_get_type(handle, &acpi_type);
343         if (ACPI_FAILURE(status))
344                 return AE_OK;
345
346         switch (acpi_type) {
347         case ACPI_TYPE_PROCESSOR:
348                 status = acpi_evaluate_object(handle, NULL, NULL, &buffer);
349                 if (ACPI_FAILURE(status))
350                         return AE_OK;
351                 acpi_id = object.processor.proc_id;
352                 pblk = object.processor.pblk_address;
353                 break;
354         case ACPI_TYPE_DEVICE:
355                 status = acpi_evaluate_integer(handle, "_UID", NULL, &tmp);
356                 if (ACPI_FAILURE(status))
357                         return AE_OK;
358                 acpi_id = tmp;
359                 break;
360         default:
361                 return AE_OK;
362         }
363         /* There are more ACPI Processor objects than in x2APIC or MADT.
364          * This can happen with incorrect ACPI SSDT declerations. */
365         if (acpi_id > nr_acpi_bits) {
366                 pr_debug("We only have %u, trying to set %u\n",
367                          nr_acpi_bits, acpi_id);
368                 return AE_OK;
369         }
370         /* OK, There is a ACPI Processor object */
371         __set_bit(acpi_id, acpi_id_present);
372
373         pr_debug("ACPI CPU%u w/ PBLK:0x%lx\n", acpi_id, (unsigned long)pblk);
374
375         status = acpi_evaluate_object(handle, "_CST", NULL, &buffer);
376         if (ACPI_FAILURE(status)) {
377                 if (!pblk)
378                         return AE_OK;
379         }
380         /* .. and it has a C-state */
381         __set_bit(acpi_id, acpi_id_cst_present);
382
383         return AE_OK;
384 }
385 static int check_acpi_ids(struct acpi_processor *pr_backup)
386 {
387
388         if (!pr_backup)
389                 return -ENODEV;
390
391         if (acpi_id_present && acpi_id_cst_present)
392                 /* OK, done this once .. skip to uploading */
393                 goto upload;
394
395         /* All online CPUs have been processed at this stage. Now verify
396          * whether in fact "online CPUs" == physical CPUs.
397          */
398         acpi_id_present = kcalloc(BITS_TO_LONGS(nr_acpi_bits), sizeof(unsigned long), GFP_KERNEL);
399         if (!acpi_id_present)
400                 return -ENOMEM;
401
402         acpi_id_cst_present = kcalloc(BITS_TO_LONGS(nr_acpi_bits), sizeof(unsigned long), GFP_KERNEL);
403         if (!acpi_id_cst_present) {
404                 kfree(acpi_id_present);
405                 return -ENOMEM;
406         }
407
408         acpi_walk_namespace(ACPI_TYPE_PROCESSOR, ACPI_ROOT_OBJECT,
409                             ACPI_UINT32_MAX,
410                             read_acpi_id, NULL, NULL, NULL);
411         acpi_get_devices(ACPI_PROCESSOR_DEVICE_HID, read_acpi_id, NULL, NULL);
412
413 upload:
414         if (!bitmap_equal(acpi_id_present, acpi_ids_done, nr_acpi_bits)) {
415                 unsigned int i;
416                 for_each_set_bit(i, acpi_id_present, nr_acpi_bits) {
417                         pr_backup->acpi_id = i;
418                         /* Mask out C-states if there are no _CST or PBLK */
419                         pr_backup->flags.power = test_bit(i, acpi_id_cst_present);
420                         (void)upload_pm_data(pr_backup);
421                 }
422         }
423
424         return 0;
425 }
426
427 /* acpi_perf_data is a pointer to percpu data. */
428 static struct acpi_processor_performance __percpu *acpi_perf_data;
429
430 static void free_acpi_perf_data(void)
431 {
432         unsigned int i;
433
434         /* Freeing a NULL pointer is OK, and alloc_percpu zeroes. */
435         for_each_possible_cpu(i)
436                 free_cpumask_var(per_cpu_ptr(acpi_perf_data, i)
437                                  ->shared_cpu_map);
438         free_percpu(acpi_perf_data);
439 }
440
441 static int xen_upload_processor_pm_data(void)
442 {
443         struct acpi_processor *pr_backup = NULL;
444         unsigned int i;
445         int rc = 0;
446
447         pr_info("Uploading Xen processor PM info\n");
448
449         for_each_possible_cpu(i) {
450                 struct acpi_processor *_pr;
451                 _pr = per_cpu(processors, i /* APIC ID */);
452                 if (!_pr)
453                         continue;
454
455                 if (!pr_backup) {
456                         pr_backup = kzalloc(sizeof(struct acpi_processor), GFP_KERNEL);
457                         if (pr_backup)
458                                 memcpy(pr_backup, _pr, sizeof(struct acpi_processor));
459                 }
460                 (void)upload_pm_data(_pr);
461         }
462
463         rc = check_acpi_ids(pr_backup);
464         kfree(pr_backup);
465
466         return rc;
467 }
468
469 static void xen_acpi_processor_resume_worker(struct work_struct *dummy)
470 {
471         int rc;
472
473         bitmap_zero(acpi_ids_done, nr_acpi_bits);
474
475         rc = xen_upload_processor_pm_data();
476         if (rc != 0)
477                 pr_info("ACPI data upload failed, error = %d\n", rc);
478 }
479
480 static void xen_acpi_processor_resume(void)
481 {
482         static DECLARE_WORK(wq, xen_acpi_processor_resume_worker);
483
484         /*
485          * xen_upload_processor_pm_data() calls non-atomic code.
486          * However, the context for xen_acpi_processor_resume is syscore
487          * with only the boot CPU online and in an atomic context.
488          *
489          * So defer the upload for some point safer.
490          */
491         schedule_work(&wq);
492 }
493
494 static struct syscore_ops xap_syscore_ops = {
495         .resume = xen_acpi_processor_resume,
496 };
497
498 static int __init xen_acpi_processor_init(void)
499 {
500         unsigned int i;
501         int rc;
502
503         if (!xen_initial_domain())
504                 return -ENODEV;
505
506         nr_acpi_bits = get_max_acpi_id() + 1;
507         acpi_ids_done = kcalloc(BITS_TO_LONGS(nr_acpi_bits), sizeof(unsigned long), GFP_KERNEL);
508         if (!acpi_ids_done)
509                 return -ENOMEM;
510
511         acpi_perf_data = alloc_percpu(struct acpi_processor_performance);
512         if (!acpi_perf_data) {
513                 pr_debug("Memory allocation error for acpi_perf_data\n");
514                 kfree(acpi_ids_done);
515                 return -ENOMEM;
516         }
517         for_each_possible_cpu(i) {
518                 if (!zalloc_cpumask_var_node(
519                         &per_cpu_ptr(acpi_perf_data, i)->shared_cpu_map,
520                         GFP_KERNEL, cpu_to_node(i))) {
521                         rc = -ENOMEM;
522                         goto err_out;
523                 }
524         }
525
526         /* Do initialization in ACPI core. It is OK to fail here. */
527         (void)acpi_processor_preregister_performance(acpi_perf_data);
528
529         for_each_possible_cpu(i) {
530                 struct acpi_processor *pr;
531                 struct acpi_processor_performance *perf;
532
533                 pr = per_cpu(processors, i);
534                 perf = per_cpu_ptr(acpi_perf_data, i);
535                 if (!pr)
536                         continue;
537
538                 pr->performance = perf;
539                 rc = acpi_processor_get_performance_info(pr);
540                 if (rc)
541                         goto err_out;
542         }
543
544         rc = xen_upload_processor_pm_data();
545         if (rc)
546                 goto err_unregister;
547
548         register_syscore_ops(&xap_syscore_ops);
549
550         return 0;
551 err_unregister:
552         for_each_possible_cpu(i)
553                 acpi_processor_unregister_performance(i);
554
555 err_out:
556         /* Freeing a NULL pointer is OK: alloc_percpu zeroes. */
557         free_acpi_perf_data();
558         kfree(acpi_ids_done);
559         return rc;
560 }
561 static void __exit xen_acpi_processor_exit(void)
562 {
563         int i;
564
565         unregister_syscore_ops(&xap_syscore_ops);
566         kfree(acpi_ids_done);
567         kfree(acpi_id_present);
568         kfree(acpi_id_cst_present);
569         for_each_possible_cpu(i)
570                 acpi_processor_unregister_performance(i);
571
572         free_acpi_perf_data();
573 }
574
575 MODULE_AUTHOR("Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>");
576 MODULE_DESCRIPTION("Xen ACPI Processor P-states (and Cx) driver which uploads PM data to Xen hypervisor");
577 MODULE_LICENSE("GPL");
578
579 /* We want to be loaded before the CPU freq scaling drivers are loaded.
580  * They are loaded in late_initcall. */
581 device_initcall(xen_acpi_processor_init);
582 module_exit(xen_acpi_processor_exit);