1 /*
2 * boot.c - Architecture-Specific Low-Level ACPI Boot Support
3 *
4 * Copyright (C) 2001, 2002 Paul Diefenbaugh <paul.s.diefenbaugh@intel.com>
5 * Copyright (C) 2001 Jun Nakajima <jun.nakajima@intel.com>
6 *
7 * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
8 *
9 * This program is free software; you can redistribute it and/or modify
10 * it under the terms of the GNU General Public License as published by
11 * the Free Software Foundation; either version 2 of the License, or
12 * (at your option) any later version.
13 *
14 * This program is distributed in the hope that it will be useful,
15 * but WITHOUT ANY WARRANTY; without even the implied warranty of
16 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
17 * GNU General Public License for more details.
18 *
19 * You should have received a copy of the GNU General Public License
20 * along with this program; if not, write to the Free Software
21 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
22 *
23 * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
24 */
25
26 #include <linux/init.h>
27 #include <linux/acpi.h>
28 #include <linux/acpi_pmtmr.h>
29 #include <linux/efi.h>
30 #include <linux/cpumask.h>
31 #include <linux/module.h>
32 #include <linux/dmi.h>
33 #include <linux/irq.h>
34 #include <linux/bootmem.h>
35 #include <linux/ioport.h>
36
37 #include <asm/pgtable.h>
38 #include <asm/io_apic.h>
39 #include <asm/apic.h>
40 #include <asm/genapic.h>
41 #include <asm/io.h>
42 #include <asm/mpspec.h>
43 #include <asm/smp.h>
44
45 #ifdef CONFIG_X86_LOCAL_APIC
46 # include <mach_apic.h>
47 #endif
48
49 static int __initdata acpi_force = 0;
50 u32 acpi_rsdt_forced;
51 #ifdef CONFIG_ACPI
52 int acpi_disabled = 0;
53 #else
54 int acpi_disabled = 1;
55 #endif
56 EXPORT_SYMBOL(acpi_disabled);
57
58 #ifdef CONFIG_X86_64
59
60 #include <asm/proto.h>
61
62 #else /* X86 */
63
64 #ifdef CONFIG_X86_LOCAL_APIC
65 #include <mach_apic.h>
66 #include <mach_mpparse.h>
67 #endif /* CONFIG_X86_LOCAL_APIC */
68
69 #endif /* X86 */
70
71 #define BAD_MADT_ENTRY(entry, end) ( \
72 (!entry) || (unsigned long)entry + sizeof(*entry) > end || \
73 ((struct acpi_subtable_header *)entry)->length < sizeof(*entry))
74
75 #define PREFIX "ACPI: "
76
77 int acpi_noirq; /* skip ACPI IRQ initialization */
78 int acpi_pci_disabled; /* skip ACPI PCI scan and IRQ initialization */
79 EXPORT_SYMBOL(acpi_pci_disabled);
80 int acpi_ht __initdata = 1; /* enable HT */
81
82 int acpi_lapic;
83 int acpi_ioapic;
84 int acpi_strict;
85
86 u8 acpi_sci_flags __initdata;
87 int acpi_sci_override_gsi __initdata;
88 int acpi_skip_timer_override __initdata;
89 int acpi_use_timer_override __initdata;
90
91 #ifdef CONFIG_X86_LOCAL_APIC
92 static u64 acpi_lapic_addr __initdata = APIC_DEFAULT_PHYS_BASE;
93 #endif
94
95 #ifndef __HAVE_ARCH_CMPXCHG
96 #warning ACPI uses CMPXCHG, i486 and later hardware
97 #endif
98
99 /* --------------------------------------------------------------------------
100 Boot-time Configuration
101 -------------------------------------------------------------------------- */
102
103 /*
104 * The default interrupt routing model is PIC (8259). This gets
105 * overridden if IOAPICs are enumerated (below).
106 */
107 enum acpi_irq_model_id acpi_irq_model = ACPI_IRQ_MODEL_PIC;
108
109
110 /*
111 * Temporarily use the virtual area starting from FIX_IO_APIC_BASE_END,
112 * to map the target physical address. The problem is that set_fixmap()
113 * provides a single page, and it is possible that the page is not
114 * sufficient.
115 * By using this area, we can map up to MAX_IO_APICS pages temporarily,
116 * i.e. until the next __va_range() call.
117 *
118 * Important Safety Note: The fixed I/O APIC page numbers are *subtracted*
119 * from the fixed base. That's why we start at FIX_IO_APIC_BASE_END and
120 * count idx down while incrementing the phys address.
121 */
__acpi_map_table(unsigned long phys,unsigned long size)122 char *__init __acpi_map_table(unsigned long phys, unsigned long size)
123 {
124 unsigned long base, offset, mapped_size;
125 int idx;
126
127 if (!phys || !size)
128 return NULL;
129
130 if (phys+size <= (max_low_pfn_mapped << PAGE_SHIFT))
131 return __va(phys);
132
133 offset = phys & (PAGE_SIZE - 1);
134 mapped_size = PAGE_SIZE - offset;
135 clear_fixmap(FIX_ACPI_END);
136 set_fixmap(FIX_ACPI_END, phys);
137 base = fix_to_virt(FIX_ACPI_END);
138
139 /*
140 * Most cases can be covered by the below.
141 */
142 idx = FIX_ACPI_END;
143 while (mapped_size < size) {
144 if (--idx < FIX_ACPI_BEGIN)
145 return NULL; /* cannot handle this */
146 phys += PAGE_SIZE;
147 clear_fixmap(idx);
148 set_fixmap(idx, phys);
149 mapped_size += PAGE_SIZE;
150 }
151
152 return ((unsigned char *)base + offset);
153 }
154
155 #ifdef CONFIG_PCI_MMCONFIG
156
157 static int acpi_mcfg_64bit_base_addr __initdata = FALSE;
158
159 /* The physical address of the MMCONFIG aperture. Set from ACPI tables. */
160 struct acpi_mcfg_allocation *pci_mmcfg_config;
161 int pci_mmcfg_config_num;
162
acpi_mcfg_oem_check(struct acpi_table_mcfg * mcfg)163 static int __init acpi_mcfg_oem_check(struct acpi_table_mcfg *mcfg)
164 {
165 if (!strcmp(mcfg->header.oem_id, "SGI"))
166 acpi_mcfg_64bit_base_addr = TRUE;
167
168 return 0;
169 }
170
acpi_parse_mcfg(struct acpi_table_header * header)171 int __init acpi_parse_mcfg(struct acpi_table_header *header)
172 {
173 struct acpi_table_mcfg *mcfg;
174 unsigned long i;
175 int config_size;
176
177 if (!header)
178 return -EINVAL;
179
180 mcfg = (struct acpi_table_mcfg *)header;
181
182 /* how many config structures do we have */
183 pci_mmcfg_config_num = 0;
184 i = header->length - sizeof(struct acpi_table_mcfg);
185 while (i >= sizeof(struct acpi_mcfg_allocation)) {
186 ++pci_mmcfg_config_num;
187 i -= sizeof(struct acpi_mcfg_allocation);
188 };
189 if (pci_mmcfg_config_num == 0) {
190 printk(KERN_ERR PREFIX "MMCONFIG has no entries\n");
191 return -ENODEV;
192 }
193
194 config_size = pci_mmcfg_config_num * sizeof(*pci_mmcfg_config);
195 pci_mmcfg_config = kmalloc(config_size, GFP_KERNEL);
196 if (!pci_mmcfg_config) {
197 printk(KERN_WARNING PREFIX
198 "No memory for MCFG config tables\n");
199 return -ENOMEM;
200 }
201
202 memcpy(pci_mmcfg_config, &mcfg[1], config_size);
203
204 acpi_mcfg_oem_check(mcfg);
205
206 for (i = 0; i < pci_mmcfg_config_num; ++i) {
207 if ((pci_mmcfg_config[i].address > 0xFFFFFFFF) &&
208 !acpi_mcfg_64bit_base_addr) {
209 printk(KERN_ERR PREFIX
210 "MMCONFIG not in low 4GB of memory\n");
211 kfree(pci_mmcfg_config);
212 pci_mmcfg_config_num = 0;
213 return -ENODEV;
214 }
215 }
216
217 return 0;
218 }
219 #endif /* CONFIG_PCI_MMCONFIG */
220
221 #ifdef CONFIG_X86_LOCAL_APIC
acpi_parse_madt(struct acpi_table_header * table)222 static int __init acpi_parse_madt(struct acpi_table_header *table)
223 {
224 struct acpi_table_madt *madt = NULL;
225
226 if (!cpu_has_apic)
227 return -EINVAL;
228
229 madt = (struct acpi_table_madt *)table;
230 if (!madt) {
231 printk(KERN_WARNING PREFIX "Unable to map MADT\n");
232 return -ENODEV;
233 }
234
235 if (madt->address) {
236 acpi_lapic_addr = (u64) madt->address;
237
238 printk(KERN_DEBUG PREFIX "Local APIC address 0x%08x\n",
239 madt->address);
240 }
241
242 acpi_madt_oem_check(madt->header.oem_id, madt->header.oem_table_id);
243
244 return 0;
245 }
246
acpi_register_lapic(int id,u8 enabled)247 static void __cpuinit acpi_register_lapic(int id, u8 enabled)
248 {
249 unsigned int ver = 0;
250
251 if (!enabled) {
252 ++disabled_cpus;
253 return;
254 }
255
256 if (boot_cpu_physical_apicid != -1U)
257 ver = apic_version[boot_cpu_physical_apicid];
258
259 generic_processor_info(id, ver);
260 }
261
262 static int __init
acpi_parse_lapic(struct acpi_subtable_header * header,const unsigned long end)263 acpi_parse_lapic(struct acpi_subtable_header * header, const unsigned long end)
264 {
265 struct acpi_madt_local_apic *processor = NULL;
266
267 processor = (struct acpi_madt_local_apic *)header;
268
269 if (BAD_MADT_ENTRY(processor, end))
270 return -EINVAL;
271
272 acpi_table_print_madt_entry(header);
273
274 /*
275 * We need to register disabled CPU as well to permit
276 * counting disabled CPUs. This allows us to size
277 * cpus_possible_map more accurately, to permit
278 * to not preallocating memory for all NR_CPUS
279 * when we use CPU hotplug.
280 */
281 acpi_register_lapic(processor->id, /* APIC ID */
282 processor->lapic_flags & ACPI_MADT_ENABLED);
283
284 return 0;
285 }
286
287 static int __init
acpi_parse_sapic(struct acpi_subtable_header * header,const unsigned long end)288 acpi_parse_sapic(struct acpi_subtable_header *header, const unsigned long end)
289 {
290 struct acpi_madt_local_sapic *processor = NULL;
291
292 processor = (struct acpi_madt_local_sapic *)header;
293
294 if (BAD_MADT_ENTRY(processor, end))
295 return -EINVAL;
296
297 acpi_table_print_madt_entry(header);
298
299 acpi_register_lapic((processor->id << 8) | processor->eid,/* APIC ID */
300 processor->lapic_flags & ACPI_MADT_ENABLED);
301
302 return 0;
303 }
304
305 static int __init
acpi_parse_lapic_addr_ovr(struct acpi_subtable_header * header,const unsigned long end)306 acpi_parse_lapic_addr_ovr(struct acpi_subtable_header * header,
307 const unsigned long end)
308 {
309 struct acpi_madt_local_apic_override *lapic_addr_ovr = NULL;
310
311 lapic_addr_ovr = (struct acpi_madt_local_apic_override *)header;
312
313 if (BAD_MADT_ENTRY(lapic_addr_ovr, end))
314 return -EINVAL;
315
316 acpi_lapic_addr = lapic_addr_ovr->address;
317
318 return 0;
319 }
320
321 static int __init
acpi_parse_lapic_nmi(struct acpi_subtable_header * header,const unsigned long end)322 acpi_parse_lapic_nmi(struct acpi_subtable_header * header, const unsigned long end)
323 {
324 struct acpi_madt_local_apic_nmi *lapic_nmi = NULL;
325
326 lapic_nmi = (struct acpi_madt_local_apic_nmi *)header;
327
328 if (BAD_MADT_ENTRY(lapic_nmi, end))
329 return -EINVAL;
330
331 acpi_table_print_madt_entry(header);
332
333 if (lapic_nmi->lint != 1)
334 printk(KERN_WARNING PREFIX "NMI not connected to LINT 1!\n");
335
336 return 0;
337 }
338
339 #endif /*CONFIG_X86_LOCAL_APIC */
340
341 #ifdef CONFIG_X86_IO_APIC
342
343 static int __init
acpi_parse_ioapic(struct acpi_subtable_header * header,const unsigned long end)344 acpi_parse_ioapic(struct acpi_subtable_header * header, const unsigned long end)
345 {
346 struct acpi_madt_io_apic *ioapic = NULL;
347
348 ioapic = (struct acpi_madt_io_apic *)header;
349
350 if (BAD_MADT_ENTRY(ioapic, end))
351 return -EINVAL;
352
353 acpi_table_print_madt_entry(header);
354
355 mp_register_ioapic(ioapic->id,
356 ioapic->address, ioapic->global_irq_base);
357
358 return 0;
359 }
360
361 /*
362 * Parse Interrupt Source Override for the ACPI SCI
363 */
acpi_sci_ioapic_setup(u32 gsi,u16 polarity,u16 trigger)364 static void __init acpi_sci_ioapic_setup(u32 gsi, u16 polarity, u16 trigger)
365 {
366 if (trigger == 0) /* compatible SCI trigger is level */
367 trigger = 3;
368
369 if (polarity == 0) /* compatible SCI polarity is low */
370 polarity = 3;
371
372 /* Command-line over-ride via acpi_sci= */
373 if (acpi_sci_flags & ACPI_MADT_TRIGGER_MASK)
374 trigger = (acpi_sci_flags & ACPI_MADT_TRIGGER_MASK) >> 2;
375
376 if (acpi_sci_flags & ACPI_MADT_POLARITY_MASK)
377 polarity = acpi_sci_flags & ACPI_MADT_POLARITY_MASK;
378
379 /*
380 * mp_config_acpi_legacy_irqs() already setup IRQs < 16
381 * If GSI is < 16, this will update its flags,
382 * else it will create a new mp_irqs[] entry.
383 */
384 mp_override_legacy_irq(gsi, polarity, trigger, gsi);
385
386 /*
387 * stash over-ride to indicate we've been here
388 * and for later update of acpi_gbl_FADT
389 */
390 acpi_sci_override_gsi = gsi;
391 return;
392 }
393
394 static int __init
acpi_parse_int_src_ovr(struct acpi_subtable_header * header,const unsigned long end)395 acpi_parse_int_src_ovr(struct acpi_subtable_header * header,
396 const unsigned long end)
397 {
398 struct acpi_madt_interrupt_override *intsrc = NULL;
399
400 intsrc = (struct acpi_madt_interrupt_override *)header;
401
402 if (BAD_MADT_ENTRY(intsrc, end))
403 return -EINVAL;
404
405 acpi_table_print_madt_entry(header);
406
407 if (intsrc->source_irq == acpi_gbl_FADT.sci_interrupt) {
408 acpi_sci_ioapic_setup(intsrc->global_irq,
409 intsrc->inti_flags & ACPI_MADT_POLARITY_MASK,
410 (intsrc->inti_flags & ACPI_MADT_TRIGGER_MASK) >> 2);
411 return 0;
412 }
413
414 if (acpi_skip_timer_override &&
415 intsrc->source_irq == 0 && intsrc->global_irq == 2) {
416 printk(PREFIX "BIOS IRQ0 pin2 override ignored.\n");
417 return 0;
418 }
419
420 mp_override_legacy_irq(intsrc->source_irq,
421 intsrc->inti_flags & ACPI_MADT_POLARITY_MASK,
422 (intsrc->inti_flags & ACPI_MADT_TRIGGER_MASK) >> 2,
423 intsrc->global_irq);
424
425 return 0;
426 }
427
428 static int __init
acpi_parse_nmi_src(struct acpi_subtable_header * header,const unsigned long end)429 acpi_parse_nmi_src(struct acpi_subtable_header * header, const unsigned long end)
430 {
431 struct acpi_madt_nmi_source *nmi_src = NULL;
432
433 nmi_src = (struct acpi_madt_nmi_source *)header;
434
435 if (BAD_MADT_ENTRY(nmi_src, end))
436 return -EINVAL;
437
438 acpi_table_print_madt_entry(header);
439
440 /* TBD: Support nimsrc entries? */
441
442 return 0;
443 }
444
445 #endif /* CONFIG_X86_IO_APIC */
446
447 /*
448 * acpi_pic_sci_set_trigger()
449 *
450 * use ELCR to set PIC-mode trigger type for SCI
451 *
452 * If a PIC-mode SCI is not recognized or gives spurious IRQ7's
453 * it may require Edge Trigger -- use "acpi_sci=edge"
454 *
455 * Port 0x4d0-4d1 are ECLR1 and ECLR2, the Edge/Level Control Registers
456 * for the 8259 PIC. bit[n] = 1 means irq[n] is Level, otherwise Edge.
457 * ECLR1 is IRQs 0-7 (IRQ 0, 1, 2 must be 0)
458 * ECLR2 is IRQs 8-15 (IRQ 8, 13 must be 0)
459 */
460
acpi_pic_sci_set_trigger(unsigned int irq,u16 trigger)461 void __init acpi_pic_sci_set_trigger(unsigned int irq, u16 trigger)
462 {
463 unsigned int mask = 1 << irq;
464 unsigned int old, new;
465
466 /* Real old ELCR mask */
467 old = inb(0x4d0) | (inb(0x4d1) << 8);
468
469 /*
470 * If we use ACPI to set PCI IRQs, then we should clear ELCR
471 * since we will set it correctly as we enable the PCI irq
472 * routing.
473 */
474 new = acpi_noirq ? old : 0;
475
476 /*
477 * Update SCI information in the ELCR, it isn't in the PCI
478 * routing tables..
479 */
480 switch (trigger) {
481 case 1: /* Edge - clear */
482 new &= ~mask;
483 break;
484 case 3: /* Level - set */
485 new |= mask;
486 break;
487 }
488
489 if (old == new)
490 return;
491
492 printk(PREFIX "setting ELCR to %04x (from %04x)\n", new, old);
493 outb(new, 0x4d0);
494 outb(new >> 8, 0x4d1);
495 }
496
acpi_gsi_to_irq(u32 gsi,unsigned int * irq)497 int acpi_gsi_to_irq(u32 gsi, unsigned int *irq)
498 {
499 *irq = gsi;
500 return 0;
501 }
502
503 /*
504 * success: return IRQ number (>=0)
505 * failure: return < 0
506 */
acpi_register_gsi(u32 gsi,int triggering,int polarity)507 int acpi_register_gsi(u32 gsi, int triggering, int polarity)
508 {
509 unsigned int irq;
510 unsigned int plat_gsi = gsi;
511
512 #ifdef CONFIG_PCI
513 /*
514 * Make sure all (legacy) PCI IRQs are set as level-triggered.
515 */
516 if (acpi_irq_model == ACPI_IRQ_MODEL_PIC) {
517 if (triggering == ACPI_LEVEL_SENSITIVE)
518 eisa_set_level_irq(gsi);
519 }
520 #endif
521
522 #ifdef CONFIG_X86_IO_APIC
523 if (acpi_irq_model == ACPI_IRQ_MODEL_IOAPIC) {
524 plat_gsi = mp_register_gsi(gsi, triggering, polarity);
525 }
526 #endif
527 acpi_gsi_to_irq(plat_gsi, &irq);
528 return irq;
529 }
530
531 /*
532 * ACPI based hotplug support for CPU
533 */
534 #ifdef CONFIG_ACPI_HOTPLUG_CPU
535
_acpi_map_lsapic(acpi_handle handle,int * pcpu)536 static int __cpuinit _acpi_map_lsapic(acpi_handle handle, int *pcpu)
537 {
538 struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
539 union acpi_object *obj;
540 struct acpi_madt_local_apic *lapic;
541 cpumask_var_t tmp_map, new_map;
542 u8 physid;
543 int cpu;
544 int retval = -ENOMEM;
545
546 if (ACPI_FAILURE(acpi_evaluate_object(handle, "_MAT", NULL, &buffer)))
547 return -EINVAL;
548
549 if (!buffer.length || !buffer.pointer)
550 return -EINVAL;
551
552 obj = buffer.pointer;
553 if (obj->type != ACPI_TYPE_BUFFER ||
554 obj->buffer.length < sizeof(*lapic)) {
555 kfree(buffer.pointer);
556 return -EINVAL;
557 }
558
559 lapic = (struct acpi_madt_local_apic *)obj->buffer.pointer;
560
561 if (lapic->header.type != ACPI_MADT_TYPE_LOCAL_APIC ||
562 !(lapic->lapic_flags & ACPI_MADT_ENABLED)) {
563 kfree(buffer.pointer);
564 return -EINVAL;
565 }
566
567 physid = lapic->id;
568
569 kfree(buffer.pointer);
570 buffer.length = ACPI_ALLOCATE_BUFFER;
571 buffer.pointer = NULL;
572
573 if (!alloc_cpumask_var(&tmp_map, GFP_KERNEL))
574 goto out;
575
576 if (!alloc_cpumask_var(&new_map, GFP_KERNEL))
577 goto free_tmp_map;
578
579 cpumask_copy(tmp_map, cpu_present_mask);
580 acpi_register_lapic(physid, lapic->lapic_flags & ACPI_MADT_ENABLED);
581
582 /*
583 * If mp_register_lapic successfully generates a new logical cpu
584 * number, then the following will get us exactly what was mapped
585 */
586 cpumask_andnot(new_map, cpu_present_mask, tmp_map);
587 if (cpumask_empty(new_map)) {
588 printk ("Unable to map lapic to logical cpu number\n");
589 retval = -EINVAL;
590 goto free_new_map;
591 }
592
593 cpu = cpumask_first(new_map);
594
595 *pcpu = cpu;
596 retval = 0;
597
598 free_new_map:
599 free_cpumask_var(new_map);
600 free_tmp_map:
601 free_cpumask_var(tmp_map);
602 out:
603 return retval;
604 }
605
606 /* wrapper to silence section mismatch warning */
acpi_map_lsapic(acpi_handle handle,int * pcpu)607 int __ref acpi_map_lsapic(acpi_handle handle, int *pcpu)
608 {
609 return _acpi_map_lsapic(handle, pcpu);
610 }
611 EXPORT_SYMBOL(acpi_map_lsapic);
612
acpi_unmap_lsapic(int cpu)613 int acpi_unmap_lsapic(int cpu)
614 {
615 per_cpu(x86_cpu_to_apicid, cpu) = -1;
616 set_cpu_present(cpu, false);
617 num_processors--;
618
619 return (0);
620 }
621
622 EXPORT_SYMBOL(acpi_unmap_lsapic);
623 #endif /* CONFIG_ACPI_HOTPLUG_CPU */
624
acpi_register_ioapic(acpi_handle handle,u64 phys_addr,u32 gsi_base)625 int acpi_register_ioapic(acpi_handle handle, u64 phys_addr, u32 gsi_base)
626 {
627 /* TBD */
628 return -EINVAL;
629 }
630
631 EXPORT_SYMBOL(acpi_register_ioapic);
632
acpi_unregister_ioapic(acpi_handle handle,u32 gsi_base)633 int acpi_unregister_ioapic(acpi_handle handle, u32 gsi_base)
634 {
635 /* TBD */
636 return -EINVAL;
637 }
638
639 EXPORT_SYMBOL(acpi_unregister_ioapic);
640
acpi_parse_sbf(struct acpi_table_header * table)641 static int __init acpi_parse_sbf(struct acpi_table_header *table)
642 {
643 struct acpi_table_boot *sb;
644
645 sb = (struct acpi_table_boot *)table;
646 if (!sb) {
647 printk(KERN_WARNING PREFIX "Unable to map SBF\n");
648 return -ENODEV;
649 }
650
651 sbf_port = sb->cmos_index; /* Save CMOS port */
652
653 return 0;
654 }
655
656 #ifdef CONFIG_HPET_TIMER
657 #include <asm/hpet.h>
658
659 static struct __initdata resource *hpet_res;
660
acpi_parse_hpet(struct acpi_table_header * table)661 static int __init acpi_parse_hpet(struct acpi_table_header *table)
662 {
663 struct acpi_table_hpet *hpet_tbl;
664
665 hpet_tbl = (struct acpi_table_hpet *)table;
666 if (!hpet_tbl) {
667 printk(KERN_WARNING PREFIX "Unable to map HPET\n");
668 return -ENODEV;
669 }
670
671 if (hpet_tbl->address.space_id != ACPI_SPACE_MEM) {
672 printk(KERN_WARNING PREFIX "HPET timers must be located in "
673 "memory.\n");
674 return -1;
675 }
676
677 hpet_address = hpet_tbl->address.address;
678
679 /*
680 * Some broken BIOSes advertise HPET at 0x0. We really do not
681 * want to allocate a resource there.
682 */
683 if (!hpet_address) {
684 printk(KERN_WARNING PREFIX
685 "HPET id: %#x base: %#lx is invalid\n",
686 hpet_tbl->id, hpet_address);
687 return 0;
688 }
689 #ifdef CONFIG_X86_64
690 /*
691 * Some even more broken BIOSes advertise HPET at
692 * 0xfed0000000000000 instead of 0xfed00000. Fix it up and add
693 * some noise:
694 */
695 if (hpet_address == 0xfed0000000000000UL) {
696 if (!hpet_force_user) {
697 printk(KERN_WARNING PREFIX "HPET id: %#x "
698 "base: 0xfed0000000000000 is bogus\n "
699 "try hpet=force on the kernel command line to "
700 "fix it up to 0xfed00000.\n", hpet_tbl->id);
701 hpet_address = 0;
702 return 0;
703 }
704 printk(KERN_WARNING PREFIX
705 "HPET id: %#x base: 0xfed0000000000000 fixed up "
706 "to 0xfed00000.\n", hpet_tbl->id);
707 hpet_address >>= 32;
708 }
709 #endif
710 printk(KERN_INFO PREFIX "HPET id: %#x base: %#lx\n",
711 hpet_tbl->id, hpet_address);
712
713 /*
714 * Allocate and initialize the HPET firmware resource for adding into
715 * the resource tree during the lateinit timeframe.
716 */
717 #define HPET_RESOURCE_NAME_SIZE 9
718 hpet_res = alloc_bootmem(sizeof(*hpet_res) + HPET_RESOURCE_NAME_SIZE);
719
720 hpet_res->name = (void *)&hpet_res[1];
721 hpet_res->flags = IORESOURCE_MEM;
722 snprintf((char *)hpet_res->name, HPET_RESOURCE_NAME_SIZE, "HPET %u",
723 hpet_tbl->sequence);
724
725 hpet_res->start = hpet_address;
726 hpet_res->end = hpet_address + (1 * 1024) - 1;
727
728 return 0;
729 }
730
731 /*
732 * hpet_insert_resource inserts the HPET resources used into the resource
733 * tree.
734 */
hpet_insert_resource(void)735 static __init int hpet_insert_resource(void)
736 {
737 if (!hpet_res)
738 return 1;
739
740 return insert_resource(&iomem_resource, hpet_res);
741 }
742
743 late_initcall(hpet_insert_resource);
744
745 #else
746 #define acpi_parse_hpet NULL
747 #endif
748
acpi_parse_fadt(struct acpi_table_header * table)749 static int __init acpi_parse_fadt(struct acpi_table_header *table)
750 {
751
752 #ifdef CONFIG_X86_PM_TIMER
753 /* detect the location of the ACPI PM Timer */
754 if (acpi_gbl_FADT.header.revision >= FADT2_REVISION_ID) {
755 /* FADT rev. 2 */
756 if (acpi_gbl_FADT.xpm_timer_block.space_id !=
757 ACPI_ADR_SPACE_SYSTEM_IO)
758 return 0;
759
760 pmtmr_ioport = acpi_gbl_FADT.xpm_timer_block.address;
761 /*
762 * "X" fields are optional extensions to the original V1.0
763 * fields, so we must selectively expand V1.0 fields if the
764 * corresponding X field is zero.
765 */
766 if (!pmtmr_ioport)
767 pmtmr_ioport = acpi_gbl_FADT.pm_timer_block;
768 } else {
769 /* FADT rev. 1 */
770 pmtmr_ioport = acpi_gbl_FADT.pm_timer_block;
771 }
772 if (pmtmr_ioport)
773 printk(KERN_INFO PREFIX "PM-Timer IO Port: %#x\n",
774 pmtmr_ioport);
775 #endif
776 return 0;
777 }
778
779 #ifdef CONFIG_X86_LOCAL_APIC
780 /*
781 * Parse LAPIC entries in MADT
782 * returns 0 on success, < 0 on error
783 */
784
acpi_register_lapic_address(unsigned long address)785 static void __init acpi_register_lapic_address(unsigned long address)
786 {
787 mp_lapic_addr = address;
788
789 set_fixmap_nocache(FIX_APIC_BASE, address);
790 if (boot_cpu_physical_apicid == -1U) {
791 boot_cpu_physical_apicid = read_apic_id();
792 apic_version[boot_cpu_physical_apicid] =
793 GET_APIC_VERSION(apic_read(APIC_LVR));
794 }
795 }
796
early_acpi_parse_madt_lapic_addr_ovr(void)797 static int __init early_acpi_parse_madt_lapic_addr_ovr(void)
798 {
799 int count;
800
801 if (!cpu_has_apic)
802 return -ENODEV;
803
804 /*
805 * Note that the LAPIC address is obtained from the MADT (32-bit value)
806 * and (optionally) overriden by a LAPIC_ADDR_OVR entry (64-bit value).
807 */
808
809 count =
810 acpi_table_parse_madt(ACPI_MADT_TYPE_LOCAL_APIC_OVERRIDE,
811 acpi_parse_lapic_addr_ovr, 0);
812 if (count < 0) {
813 printk(KERN_ERR PREFIX
814 "Error parsing LAPIC address override entry\n");
815 return count;
816 }
817
818 acpi_register_lapic_address(acpi_lapic_addr);
819
820 return count;
821 }
822
acpi_parse_madt_lapic_entries(void)823 static int __init acpi_parse_madt_lapic_entries(void)
824 {
825 int count;
826
827 if (!cpu_has_apic)
828 return -ENODEV;
829
830 /*
831 * Note that the LAPIC address is obtained from the MADT (32-bit value)
832 * and (optionally) overriden by a LAPIC_ADDR_OVR entry (64-bit value).
833 */
834
835 count =
836 acpi_table_parse_madt(ACPI_MADT_TYPE_LOCAL_APIC_OVERRIDE,
837 acpi_parse_lapic_addr_ovr, 0);
838 if (count < 0) {
839 printk(KERN_ERR PREFIX
840 "Error parsing LAPIC address override entry\n");
841 return count;
842 }
843
844 acpi_register_lapic_address(acpi_lapic_addr);
845
846 count = acpi_table_parse_madt(ACPI_MADT_TYPE_LOCAL_SAPIC,
847 acpi_parse_sapic, MAX_APICS);
848
849 if (!count)
850 count = acpi_table_parse_madt(ACPI_MADT_TYPE_LOCAL_APIC,
851 acpi_parse_lapic, MAX_APICS);
852 if (!count) {
853 printk(KERN_ERR PREFIX "No LAPIC entries present\n");
854 /* TBD: Cleanup to allow fallback to MPS */
855 return -ENODEV;
856 } else if (count < 0) {
857 printk(KERN_ERR PREFIX "Error parsing LAPIC entry\n");
858 /* TBD: Cleanup to allow fallback to MPS */
859 return count;
860 }
861
862 count =
863 acpi_table_parse_madt(ACPI_MADT_TYPE_LOCAL_APIC_NMI, acpi_parse_lapic_nmi, 0);
864 if (count < 0) {
865 printk(KERN_ERR PREFIX "Error parsing LAPIC NMI entry\n");
866 /* TBD: Cleanup to allow fallback to MPS */
867 return count;
868 }
869 return 0;
870 }
871 #endif /* CONFIG_X86_LOCAL_APIC */
872
873 #ifdef CONFIG_X86_IO_APIC
874 #define MP_ISA_BUS 0
875
876 #ifdef CONFIG_X86_ES7000
877 extern int es7000_plat;
878 #endif
879
880 static struct {
881 int apic_id;
882 int gsi_base;
883 int gsi_end;
884 DECLARE_BITMAP(pin_programmed, MP_MAX_IOAPIC_PIN + 1);
885 } mp_ioapic_routing[MAX_IO_APICS];
886
mp_find_ioapic(int gsi)887 static int mp_find_ioapic(int gsi)
888 {
889 int i = 0;
890
891 /* Find the IOAPIC that manages this GSI. */
892 for (i = 0; i < nr_ioapics; i++) {
893 if ((gsi >= mp_ioapic_routing[i].gsi_base)
894 && (gsi <= mp_ioapic_routing[i].gsi_end))
895 return i;
896 }
897
898 printk(KERN_ERR "ERROR: Unable to locate IOAPIC for GSI %d\n", gsi);
899 return -1;
900 }
901
uniq_ioapic_id(u8 id)902 static u8 __init uniq_ioapic_id(u8 id)
903 {
904 #ifdef CONFIG_X86_32
905 if ((boot_cpu_data.x86_vendor == X86_VENDOR_INTEL) &&
906 !APIC_XAPIC(apic_version[boot_cpu_physical_apicid]))
907 return io_apic_get_unique_id(nr_ioapics, id);
908 else
909 return id;
910 #else
911 int i;
912 DECLARE_BITMAP(used, 256);
913 bitmap_zero(used, 256);
914 for (i = 0; i < nr_ioapics; i++) {
915 struct mp_config_ioapic *ia = &mp_ioapics[i];
916 __set_bit(ia->mp_apicid, used);
917 }
918 if (!test_bit(id, used))
919 return id;
920 return find_first_zero_bit(used, 256);
921 #endif
922 }
923
bad_ioapic(unsigned long address)924 static int bad_ioapic(unsigned long address)
925 {
926 if (nr_ioapics >= MAX_IO_APICS) {
927 printk(KERN_ERR "ERROR: Max # of I/O APICs (%d) exceeded "
928 "(found %d)\n", MAX_IO_APICS, nr_ioapics);
929 panic("Recompile kernel with bigger MAX_IO_APICS!\n");
930 }
931 if (!address) {
932 printk(KERN_ERR "WARNING: Bogus (zero) I/O APIC address"
933 " found in table, skipping!\n");
934 return 1;
935 }
936 return 0;
937 }
938
mp_register_ioapic(int id,u32 address,u32 gsi_base)939 void __init mp_register_ioapic(int id, u32 address, u32 gsi_base)
940 {
941 int idx = 0;
942
943 if (bad_ioapic(address))
944 return;
945
946 idx = nr_ioapics;
947
948 mp_ioapics[idx].mp_type = MP_IOAPIC;
949 mp_ioapics[idx].mp_flags = MPC_APIC_USABLE;
950 mp_ioapics[idx].mp_apicaddr = address;
951
952 set_fixmap_nocache(FIX_IO_APIC_BASE_0 + idx, address);
953 mp_ioapics[idx].mp_apicid = uniq_ioapic_id(id);
954 #ifdef CONFIG_X86_32
955 mp_ioapics[idx].mp_apicver = io_apic_get_version(idx);
956 #else
957 mp_ioapics[idx].mp_apicver = 0;
958 #endif
959 /*
960 * Build basic GSI lookup table to facilitate gsi->io_apic lookups
961 * and to prevent reprogramming of IOAPIC pins (PCI GSIs).
962 */
963 mp_ioapic_routing[idx].apic_id = mp_ioapics[idx].mp_apicid;
964 mp_ioapic_routing[idx].gsi_base = gsi_base;
965 mp_ioapic_routing[idx].gsi_end = gsi_base +
966 io_apic_get_redir_entries(idx);
967
968 printk(KERN_INFO "IOAPIC[%d]: apic_id %d, version %d, address 0x%lx, "
969 "GSI %d-%d\n", idx, mp_ioapics[idx].mp_apicid,
970 mp_ioapics[idx].mp_apicver, mp_ioapics[idx].mp_apicaddr,
971 mp_ioapic_routing[idx].gsi_base, mp_ioapic_routing[idx].gsi_end);
972
973 nr_ioapics++;
974 }
975
acpi_probe_gsi(void)976 int __init acpi_probe_gsi(void)
977 {
978 int idx;
979 int gsi;
980 int max_gsi = 0;
981
982 if (acpi_disabled)
983 return 0;
984
985 if (!acpi_ioapic)
986 return 0;
987
988 max_gsi = 0;
989 for (idx = 0; idx < nr_ioapics; idx++) {
990 gsi = mp_ioapic_routing[idx].gsi_end;
991
992 if (gsi > max_gsi)
993 max_gsi = gsi;
994 }
995
996 return max_gsi + 1;
997 }
998
assign_to_mp_irq(struct mp_config_intsrc * m,struct mp_config_intsrc * mp_irq)999 static void assign_to_mp_irq(struct mp_config_intsrc *m,
1000 struct mp_config_intsrc *mp_irq)
1001 {
1002 memcpy(mp_irq, m, sizeof(struct mp_config_intsrc));
1003 }
1004
mp_irq_cmp(struct mp_config_intsrc * mp_irq,struct mp_config_intsrc * m)1005 static int mp_irq_cmp(struct mp_config_intsrc *mp_irq,
1006 struct mp_config_intsrc *m)
1007 {
1008 return memcmp(mp_irq, m, sizeof(struct mp_config_intsrc));
1009 }
1010
save_mp_irq(struct mp_config_intsrc * m)1011 static void save_mp_irq(struct mp_config_intsrc *m)
1012 {
1013 int i;
1014
1015 for (i = 0; i < mp_irq_entries; i++) {
1016 if (!mp_irq_cmp(&mp_irqs[i], m))
1017 return;
1018 }
1019
1020 assign_to_mp_irq(m, &mp_irqs[mp_irq_entries]);
1021 if (++mp_irq_entries == MAX_IRQ_SOURCES)
1022 panic("Max # of irq sources exceeded!!\n");
1023 }
1024
mp_override_legacy_irq(u8 bus_irq,u8 polarity,u8 trigger,u32 gsi)1025 void __init mp_override_legacy_irq(u8 bus_irq, u8 polarity, u8 trigger, u32 gsi)
1026 {
1027 int ioapic;
1028 int pin;
1029 struct mp_config_intsrc mp_irq;
1030
1031 /*
1032 * Convert 'gsi' to 'ioapic.pin'.
1033 */
1034 ioapic = mp_find_ioapic(gsi);
1035 if (ioapic < 0)
1036 return;
1037 pin = gsi - mp_ioapic_routing[ioapic].gsi_base;
1038
1039 /*
1040 * TBD: This check is for faulty timer entries, where the override
1041 * erroneously sets the trigger to level, resulting in a HUGE
1042 * increase of timer interrupts!
1043 */
1044 if ((bus_irq == 0) && (trigger == 3))
1045 trigger = 1;
1046
1047 mp_irq.mp_type = MP_INTSRC;
1048 mp_irq.mp_irqtype = mp_INT;
1049 mp_irq.mp_irqflag = (trigger << 2) | polarity;
1050 mp_irq.mp_srcbus = MP_ISA_BUS;
1051 mp_irq.mp_srcbusirq = bus_irq; /* IRQ */
1052 mp_irq.mp_dstapic = mp_ioapics[ioapic].mp_apicid; /* APIC ID */
1053 mp_irq.mp_dstirq = pin; /* INTIN# */
1054
1055 save_mp_irq(&mp_irq);
1056 }
1057
mp_config_acpi_legacy_irqs(void)1058 void __init mp_config_acpi_legacy_irqs(void)
1059 {
1060 int i;
1061 int ioapic;
1062 unsigned int dstapic;
1063 struct mp_config_intsrc mp_irq;
1064
1065 #if defined (CONFIG_MCA) || defined (CONFIG_EISA)
1066 /*
1067 * Fabricate the legacy ISA bus (bus #31).
1068 */
1069 mp_bus_id_to_type[MP_ISA_BUS] = MP_BUS_ISA;
1070 #endif
1071 set_bit(MP_ISA_BUS, mp_bus_not_pci);
1072 pr_debug("Bus #%d is ISA\n", MP_ISA_BUS);
1073
1074 #ifdef CONFIG_X86_ES7000
1075 /*
1076 * Older generations of ES7000 have no legacy identity mappings
1077 */
1078 if (es7000_plat == 1)
1079 return;
1080 #endif
1081
1082 /*
1083 * Locate the IOAPIC that manages the ISA IRQs (0-15).
1084 */
1085 ioapic = mp_find_ioapic(0);
1086 if (ioapic < 0)
1087 return;
1088 dstapic = mp_ioapics[ioapic].mp_apicid;
1089
1090 /*
1091 * Use the default configuration for the IRQs 0-15. Unless
1092 * overridden by (MADT) interrupt source override entries.
1093 */
1094 for (i = 0; i < 16; i++) {
1095 int idx;
1096
1097 for (idx = 0; idx < mp_irq_entries; idx++) {
1098 struct mp_config_intsrc *irq = mp_irqs + idx;
1099
1100 /* Do we already have a mapping for this ISA IRQ? */
1101 if (irq->mp_srcbus == MP_ISA_BUS
1102 && irq->mp_srcbusirq == i)
1103 break;
1104
1105 /* Do we already have a mapping for this IOAPIC pin */
1106 if (irq->mp_dstapic == dstapic &&
1107 irq->mp_dstirq == i)
1108 break;
1109 }
1110
1111 if (idx != mp_irq_entries) {
1112 printk(KERN_DEBUG "ACPI: IRQ%d used by override.\n", i);
1113 continue; /* IRQ already used */
1114 }
1115
1116 mp_irq.mp_type = MP_INTSRC;
1117 mp_irq.mp_irqflag = 0; /* Conforming */
1118 mp_irq.mp_srcbus = MP_ISA_BUS;
1119 mp_irq.mp_dstapic = dstapic;
1120 mp_irq.mp_irqtype = mp_INT;
1121 mp_irq.mp_srcbusirq = i; /* Identity mapped */
1122 mp_irq.mp_dstirq = i;
1123
1124 save_mp_irq(&mp_irq);
1125 }
1126 }
1127
mp_register_gsi(u32 gsi,int triggering,int polarity)1128 int mp_register_gsi(u32 gsi, int triggering, int polarity)
1129 {
1130 int ioapic;
1131 int ioapic_pin;
1132 #ifdef CONFIG_X86_32
1133 #define MAX_GSI_NUM 4096
1134 #define IRQ_COMPRESSION_START 64
1135
1136 static int pci_irq = IRQ_COMPRESSION_START;
1137 /*
1138 * Mapping between Global System Interrupts, which
1139 * represent all possible interrupts, and IRQs
1140 * assigned to actual devices.
1141 */
1142 static int gsi_to_irq[MAX_GSI_NUM];
1143 #else
1144
1145 if (acpi_irq_model != ACPI_IRQ_MODEL_IOAPIC)
1146 return gsi;
1147 #endif
1148
1149 /* Don't set up the ACPI SCI because it's already set up */
1150 if (acpi_gbl_FADT.sci_interrupt == gsi)
1151 return gsi;
1152
1153 ioapic = mp_find_ioapic(gsi);
1154 if (ioapic < 0) {
1155 printk(KERN_WARNING "No IOAPIC for GSI %u\n", gsi);
1156 return gsi;
1157 }
1158
1159 ioapic_pin = gsi - mp_ioapic_routing[ioapic].gsi_base;
1160
1161 #ifdef CONFIG_X86_32
1162 if (ioapic_renumber_irq)
1163 gsi = ioapic_renumber_irq(ioapic, gsi);
1164 #endif
1165
1166 /*
1167 * Avoid pin reprogramming. PRTs typically include entries
1168 * with redundant pin->gsi mappings (but unique PCI devices);
1169 * we only program the IOAPIC on the first.
1170 */
1171 if (ioapic_pin > MP_MAX_IOAPIC_PIN) {
1172 printk(KERN_ERR "Invalid reference to IOAPIC pin "
1173 "%d-%d\n", mp_ioapic_routing[ioapic].apic_id,
1174 ioapic_pin);
1175 return gsi;
1176 }
1177 if (test_bit(ioapic_pin, mp_ioapic_routing[ioapic].pin_programmed)) {
1178 pr_debug("Pin %d-%d already programmed\n",
1179 mp_ioapic_routing[ioapic].apic_id, ioapic_pin);
1180 #ifdef CONFIG_X86_32
1181 return (gsi < IRQ_COMPRESSION_START ? gsi : gsi_to_irq[gsi]);
1182 #else
1183 return gsi;
1184 #endif
1185 }
1186
1187 set_bit(ioapic_pin, mp_ioapic_routing[ioapic].pin_programmed);
1188 #ifdef CONFIG_X86_32
1189 /*
1190 * For GSI >= 64, use IRQ compression
1191 */
1192 if ((gsi >= IRQ_COMPRESSION_START)
1193 && (triggering == ACPI_LEVEL_SENSITIVE)) {
1194 /*
1195 * For PCI devices assign IRQs in order, avoiding gaps
1196 * due to unused I/O APIC pins.
1197 */
1198 int irq = gsi;
1199 if (gsi < MAX_GSI_NUM) {
1200 /*
1201 * Retain the VIA chipset work-around (gsi > 15), but
1202 * avoid a problem where the 8254 timer (IRQ0) is setup
1203 * via an override (so it's not on pin 0 of the ioapic),
1204 * and at the same time, the pin 0 interrupt is a PCI
1205 * type. The gsi > 15 test could cause these two pins
1206 * to be shared as IRQ0, and they are not shareable.
1207 * So test for this condition, and if necessary, avoid
1208 * the pin collision.
1209 */
1210 gsi = pci_irq++;
1211 /*
1212 * Don't assign IRQ used by ACPI SCI
1213 */
1214 if (gsi == acpi_gbl_FADT.sci_interrupt)
1215 gsi = pci_irq++;
1216 gsi_to_irq[irq] = gsi;
1217 } else {
1218 printk(KERN_ERR "GSI %u is too high\n", gsi);
1219 return gsi;
1220 }
1221 }
1222 #endif
1223 io_apic_set_pci_routing(ioapic, ioapic_pin, gsi,
1224 triggering == ACPI_EDGE_SENSITIVE ? 0 : 1,
1225 polarity == ACPI_ACTIVE_HIGH ? 0 : 1);
1226 return gsi;
1227 }
1228
mp_config_acpi_gsi(unsigned char number,unsigned int devfn,u8 pin,u32 gsi,int triggering,int polarity)1229 int mp_config_acpi_gsi(unsigned char number, unsigned int devfn, u8 pin,
1230 u32 gsi, int triggering, int polarity)
1231 {
1232 #ifdef CONFIG_X86_MPPARSE
1233 struct mp_config_intsrc mp_irq;
1234 int ioapic;
1235
1236 if (!acpi_ioapic)
1237 return 0;
1238
1239 /* print the entry should happen on mptable identically */
1240 mp_irq.mp_type = MP_INTSRC;
1241 mp_irq.mp_irqtype = mp_INT;
1242 mp_irq.mp_irqflag = (triggering == ACPI_EDGE_SENSITIVE ? 4 : 0x0c) |
1243 (polarity == ACPI_ACTIVE_HIGH ? 1 : 3);
1244 mp_irq.mp_srcbus = number;
1245 mp_irq.mp_srcbusirq = (((devfn >> 3) & 0x1f) << 2) | ((pin - 1) & 3);
1246 ioapic = mp_find_ioapic(gsi);
1247 mp_irq.mp_dstapic = mp_ioapic_routing[ioapic].apic_id;
1248 mp_irq.mp_dstirq = gsi - mp_ioapic_routing[ioapic].gsi_base;
1249
1250 save_mp_irq(&mp_irq);
1251 #endif
1252 return 0;
1253 }
1254
1255 /*
1256 * Parse IOAPIC related entries in MADT
1257 * returns 0 on success, < 0 on error
1258 */
acpi_parse_madt_ioapic_entries(void)1259 static int __init acpi_parse_madt_ioapic_entries(void)
1260 {
1261 int count;
1262
1263 /*
1264 * ACPI interpreter is required to complete interrupt setup,
1265 * so if it is off, don't enumerate the io-apics with ACPI.
1266 * If MPS is present, it will handle them,
1267 * otherwise the system will stay in PIC mode
1268 */
1269 if (acpi_disabled || acpi_noirq) {
1270 return -ENODEV;
1271 }
1272
1273 if (!cpu_has_apic)
1274 return -ENODEV;
1275
1276 /*
1277 * if "noapic" boot option, don't look for IO-APICs
1278 */
1279 if (skip_ioapic_setup) {
1280 printk(KERN_INFO PREFIX "Skipping IOAPIC probe "
1281 "due to 'noapic' option.\n");
1282 return -ENODEV;
1283 }
1284
1285 count =
1286 acpi_table_parse_madt(ACPI_MADT_TYPE_IO_APIC, acpi_parse_ioapic,
1287 MAX_IO_APICS);
1288 if (!count) {
1289 printk(KERN_ERR PREFIX "No IOAPIC entries present\n");
1290 return -ENODEV;
1291 } else if (count < 0) {
1292 printk(KERN_ERR PREFIX "Error parsing IOAPIC entry\n");
1293 return count;
1294 }
1295
1296 count =
1297 acpi_table_parse_madt(ACPI_MADT_TYPE_INTERRUPT_OVERRIDE, acpi_parse_int_src_ovr,
1298 nr_irqs);
1299 if (count < 0) {
1300 printk(KERN_ERR PREFIX
1301 "Error parsing interrupt source overrides entry\n");
1302 /* TBD: Cleanup to allow fallback to MPS */
1303 return count;
1304 }
1305
1306 /*
1307 * If BIOS did not supply an INT_SRC_OVR for the SCI
1308 * pretend we got one so we can set the SCI flags.
1309 */
1310 if (!acpi_sci_override_gsi)
1311 acpi_sci_ioapic_setup(acpi_gbl_FADT.sci_interrupt, 0, 0);
1312
1313 /* Fill in identity legacy mapings where no override */
1314 mp_config_acpi_legacy_irqs();
1315
1316 count =
1317 acpi_table_parse_madt(ACPI_MADT_TYPE_NMI_SOURCE, acpi_parse_nmi_src,
1318 nr_irqs);
1319 if (count < 0) {
1320 printk(KERN_ERR PREFIX "Error parsing NMI SRC entry\n");
1321 /* TBD: Cleanup to allow fallback to MPS */
1322 return count;
1323 }
1324
1325 return 0;
1326 }
1327 #else
acpi_parse_madt_ioapic_entries(void)1328 static inline int acpi_parse_madt_ioapic_entries(void)
1329 {
1330 return -1;
1331 }
1332 #endif /* !CONFIG_X86_IO_APIC */
1333
early_acpi_process_madt(void)1334 static void __init early_acpi_process_madt(void)
1335 {
1336 #ifdef CONFIG_X86_LOCAL_APIC
1337 int error;
1338
1339 if (!acpi_table_parse(ACPI_SIG_MADT, acpi_parse_madt)) {
1340
1341 /*
1342 * Parse MADT LAPIC entries
1343 */
1344 error = early_acpi_parse_madt_lapic_addr_ovr();
1345 if (!error) {
1346 acpi_lapic = 1;
1347 smp_found_config = 1;
1348 }
1349 if (error == -EINVAL) {
1350 /*
1351 * Dell Precision Workstation 410, 610 come here.
1352 */
1353 printk(KERN_ERR PREFIX
1354 "Invalid BIOS MADT, disabling ACPI\n");
1355 disable_acpi();
1356 }
1357 }
1358 #endif
1359 }
1360
acpi_process_madt(void)1361 static void __init acpi_process_madt(void)
1362 {
1363 #ifdef CONFIG_X86_LOCAL_APIC
1364 int error;
1365
1366 if (!acpi_table_parse(ACPI_SIG_MADT, acpi_parse_madt)) {
1367
1368 /*
1369 * Parse MADT LAPIC entries
1370 */
1371 error = acpi_parse_madt_lapic_entries();
1372 if (!error) {
1373 acpi_lapic = 1;
1374
1375 #ifdef CONFIG_X86_GENERICARCH
1376 generic_bigsmp_probe();
1377 #endif
1378 /*
1379 * Parse MADT IO-APIC entries
1380 */
1381 error = acpi_parse_madt_ioapic_entries();
1382 if (!error) {
1383 acpi_irq_model = ACPI_IRQ_MODEL_IOAPIC;
1384 acpi_ioapic = 1;
1385
1386 smp_found_config = 1;
1387 #ifdef CONFIG_X86_32
1388 setup_apic_routing();
1389 #endif
1390 }
1391 }
1392 if (error == -EINVAL) {
1393 /*
1394 * Dell Precision Workstation 410, 610 come here.
1395 */
1396 printk(KERN_ERR PREFIX
1397 "Invalid BIOS MADT, disabling ACPI\n");
1398 disable_acpi();
1399 }
1400 } else {
1401 /*
1402 * ACPI found no MADT, and so ACPI wants UP PIC mode.
1403 * In the event an MPS table was found, forget it.
1404 * Boot with "acpi=off" to use MPS on such a system.
1405 */
1406 if (smp_found_config) {
1407 printk(KERN_WARNING PREFIX
1408 "No APIC-table, disabling MPS\n");
1409 smp_found_config = 0;
1410 }
1411 }
1412
1413 /*
1414 * ACPI supports both logical (e.g. Hyper-Threading) and physical
1415 * processors, where MPS only supports physical.
1416 */
1417 if (acpi_lapic && acpi_ioapic)
1418 printk(KERN_INFO "Using ACPI (MADT) for SMP configuration "
1419 "information\n");
1420 else if (acpi_lapic)
1421 printk(KERN_INFO "Using ACPI for processor (LAPIC) "
1422 "configuration information\n");
1423 #endif
1424 return;
1425 }
1426
disable_acpi_irq(const struct dmi_system_id * d)1427 static int __init disable_acpi_irq(const struct dmi_system_id *d)
1428 {
1429 if (!acpi_force) {
1430 printk(KERN_NOTICE "%s detected: force use of acpi=noirq\n",
1431 d->ident);
1432 acpi_noirq_set();
1433 }
1434 return 0;
1435 }
1436
disable_acpi_pci(const struct dmi_system_id * d)1437 static int __init disable_acpi_pci(const struct dmi_system_id *d)
1438 {
1439 if (!acpi_force) {
1440 printk(KERN_NOTICE "%s detected: force use of pci=noacpi\n",
1441 d->ident);
1442 acpi_disable_pci();
1443 }
1444 return 0;
1445 }
1446
dmi_disable_acpi(const struct dmi_system_id * d)1447 static int __init dmi_disable_acpi(const struct dmi_system_id *d)
1448 {
1449 if (!acpi_force) {
1450 printk(KERN_NOTICE "%s detected: acpi off\n", d->ident);
1451 disable_acpi();
1452 } else {
1453 printk(KERN_NOTICE
1454 "Warning: DMI blacklist says broken, but acpi forced\n");
1455 }
1456 return 0;
1457 }
1458
1459 /*
1460 * Limit ACPI to CPU enumeration for HT
1461 */
force_acpi_ht(const struct dmi_system_id * d)1462 static int __init force_acpi_ht(const struct dmi_system_id *d)
1463 {
1464 if (!acpi_force) {
1465 printk(KERN_NOTICE "%s detected: force use of acpi=ht\n",
1466 d->ident);
1467 disable_acpi();
1468 acpi_ht = 1;
1469 } else {
1470 printk(KERN_NOTICE
1471 "Warning: acpi=force overrules DMI blacklist: acpi=ht\n");
1472 }
1473 return 0;
1474 }
1475
1476 /*
1477 * Force ignoring BIOS IRQ0 pin2 override
1478 */
dmi_ignore_irq0_timer_override(const struct dmi_system_id * d)1479 static int __init dmi_ignore_irq0_timer_override(const struct dmi_system_id *d)
1480 {
1481 /*
1482 * The ati_ixp4x0_rev() early PCI quirk should have set
1483 * the acpi_skip_timer_override flag already:
1484 */
1485 if (!acpi_skip_timer_override) {
1486 WARN(1, KERN_ERR "ati_ixp4x0 quirk not complete.\n");
1487 pr_notice("%s detected: Ignoring BIOS IRQ0 pin2 override\n",
1488 d->ident);
1489 acpi_skip_timer_override = 1;
1490 }
1491 return 0;
1492 }
1493
1494 /*
1495 * If your system is blacklisted here, but you find that acpi=force
1496 * works for you, please contact acpi-devel@sourceforge.net
1497 */
1498 static struct dmi_system_id __initdata acpi_dmi_table[] = {
1499 /*
1500 * Boxes that need ACPI disabled
1501 */
1502 {
1503 .callback = dmi_disable_acpi,
1504 .ident = "IBM Thinkpad",
1505 .matches = {
1506 DMI_MATCH(DMI_BOARD_VENDOR, "IBM"),
1507 DMI_MATCH(DMI_BOARD_NAME, "2629H1G"),
1508 },
1509 },
1510
1511 /*
1512 * Boxes that need acpi=ht
1513 */
1514 {
1515 .callback = force_acpi_ht,
1516 .ident = "FSC Primergy T850",
1517 .matches = {
1518 DMI_MATCH(DMI_SYS_VENDOR, "FUJITSU SIEMENS"),
1519 DMI_MATCH(DMI_PRODUCT_NAME, "PRIMERGY T850"),
1520 },
1521 },
1522 {
1523 .callback = force_acpi_ht,
1524 .ident = "HP VISUALIZE NT Workstation",
1525 .matches = {
1526 DMI_MATCH(DMI_BOARD_VENDOR, "Hewlett-Packard"),
1527 DMI_MATCH(DMI_PRODUCT_NAME, "HP VISUALIZE NT Workstation"),
1528 },
1529 },
1530 {
1531 .callback = force_acpi_ht,
1532 .ident = "Compaq Workstation W8000",
1533 .matches = {
1534 DMI_MATCH(DMI_SYS_VENDOR, "Compaq"),
1535 DMI_MATCH(DMI_PRODUCT_NAME, "Workstation W8000"),
1536 },
1537 },
1538 {
1539 .callback = force_acpi_ht,
1540 .ident = "ASUS P4B266",
1541 .matches = {
1542 DMI_MATCH(DMI_BOARD_VENDOR, "ASUSTeK Computer INC."),
1543 DMI_MATCH(DMI_BOARD_NAME, "P4B266"),
1544 },
1545 },
1546 {
1547 .callback = force_acpi_ht,
1548 .ident = "ASUS P2B-DS",
1549 .matches = {
1550 DMI_MATCH(DMI_BOARD_VENDOR, "ASUSTeK Computer INC."),
1551 DMI_MATCH(DMI_BOARD_NAME, "P2B-DS"),
1552 },
1553 },
1554 {
1555 .callback = force_acpi_ht,
1556 .ident = "ASUS CUR-DLS",
1557 .matches = {
1558 DMI_MATCH(DMI_BOARD_VENDOR, "ASUSTeK Computer INC."),
1559 DMI_MATCH(DMI_BOARD_NAME, "CUR-DLS"),
1560 },
1561 },
1562 {
1563 .callback = force_acpi_ht,
1564 .ident = "ABIT i440BX-W83977",
1565 .matches = {
1566 DMI_MATCH(DMI_BOARD_VENDOR, "ABIT <http://www.abit.com>"),
1567 DMI_MATCH(DMI_BOARD_NAME, "i440BX-W83977 (BP6)"),
1568 },
1569 },
1570 {
1571 .callback = force_acpi_ht,
1572 .ident = "IBM Bladecenter",
1573 .matches = {
1574 DMI_MATCH(DMI_BOARD_VENDOR, "IBM"),
1575 DMI_MATCH(DMI_BOARD_NAME, "IBM eServer BladeCenter HS20"),
1576 },
1577 },
1578 {
1579 .callback = force_acpi_ht,
1580 .ident = "IBM eServer xSeries 360",
1581 .matches = {
1582 DMI_MATCH(DMI_BOARD_VENDOR, "IBM"),
1583 DMI_MATCH(DMI_BOARD_NAME, "eServer xSeries 360"),
1584 },
1585 },
1586 {
1587 .callback = force_acpi_ht,
1588 .ident = "IBM eserver xSeries 330",
1589 .matches = {
1590 DMI_MATCH(DMI_BOARD_VENDOR, "IBM"),
1591 DMI_MATCH(DMI_BOARD_NAME, "eserver xSeries 330"),
1592 },
1593 },
1594 {
1595 .callback = force_acpi_ht,
1596 .ident = "IBM eserver xSeries 440",
1597 .matches = {
1598 DMI_MATCH(DMI_BOARD_VENDOR, "IBM"),
1599 DMI_MATCH(DMI_PRODUCT_NAME, "eserver xSeries 440"),
1600 },
1601 },
1602
1603 /*
1604 * Boxes that need ACPI PCI IRQ routing disabled
1605 */
1606 {
1607 .callback = disable_acpi_irq,
1608 .ident = "ASUS A7V",
1609 .matches = {
1610 DMI_MATCH(DMI_BOARD_VENDOR, "ASUSTeK Computer INC"),
1611 DMI_MATCH(DMI_BOARD_NAME, "<A7V>"),
1612 /* newer BIOS, Revision 1011, does work */
1613 DMI_MATCH(DMI_BIOS_VERSION,
1614 "ASUS A7V ACPI BIOS Revision 1007"),
1615 },
1616 },
1617 {
1618 /*
1619 * Latest BIOS for IBM 600E (1.16) has bad pcinum
1620 * for LPC bridge, which is needed for the PCI
1621 * interrupt links to work. DSDT fix is in bug 5966.
1622 * 2645, 2646 model numbers are shared with 600/600E/600X
1623 */
1624 .callback = disable_acpi_irq,
1625 .ident = "IBM Thinkpad 600 Series 2645",
1626 .matches = {
1627 DMI_MATCH(DMI_BOARD_VENDOR, "IBM"),
1628 DMI_MATCH(DMI_BOARD_NAME, "2645"),
1629 },
1630 },
1631 {
1632 .callback = disable_acpi_irq,
1633 .ident = "IBM Thinkpad 600 Series 2646",
1634 .matches = {
1635 DMI_MATCH(DMI_BOARD_VENDOR, "IBM"),
1636 DMI_MATCH(DMI_BOARD_NAME, "2646"),
1637 },
1638 },
1639 /*
1640 * Boxes that need ACPI PCI IRQ routing and PCI scan disabled
1641 */
1642 { /* _BBN 0 bug */
1643 .callback = disable_acpi_pci,
1644 .ident = "ASUS PR-DLS",
1645 .matches = {
1646 DMI_MATCH(DMI_BOARD_VENDOR, "ASUSTeK Computer INC."),
1647 DMI_MATCH(DMI_BOARD_NAME, "PR-DLS"),
1648 DMI_MATCH(DMI_BIOS_VERSION,
1649 "ASUS PR-DLS ACPI BIOS Revision 1010"),
1650 DMI_MATCH(DMI_BIOS_DATE, "03/21/2003")
1651 },
1652 },
1653 {
1654 .callback = disable_acpi_pci,
1655 .ident = "Acer TravelMate 36x Laptop",
1656 .matches = {
1657 DMI_MATCH(DMI_SYS_VENDOR, "Acer"),
1658 DMI_MATCH(DMI_PRODUCT_NAME, "TravelMate 360"),
1659 },
1660 },
1661 {}
1662 };
1663
1664 /* second table for DMI checks that should run after early-quirks */
1665 static struct dmi_system_id __initdata acpi_dmi_table_late[] = {
1666 /*
1667 * HP laptops which use a DSDT reporting as HP/SB400/10000,
1668 * which includes some code which overrides all temperature
1669 * trip points to 16C if the INTIN2 input of the I/O APIC
1670 * is enabled. This input is incorrectly designated the
1671 * ISA IRQ 0 via an interrupt source override even though
1672 * it is wired to the output of the master 8259A and INTIN0
1673 * is not connected at all. Force ignoring BIOS IRQ0 pin2
1674 * override in that cases.
1675 */
1676 {
1677 .callback = dmi_ignore_irq0_timer_override,
1678 .ident = "HP nx6115 laptop",
1679 .matches = {
1680 DMI_MATCH(DMI_SYS_VENDOR, "Hewlett-Packard"),
1681 DMI_MATCH(DMI_PRODUCT_NAME, "HP Compaq nx6115"),
1682 },
1683 },
1684 {
1685 .callback = dmi_ignore_irq0_timer_override,
1686 .ident = "HP NX6125 laptop",
1687 .matches = {
1688 DMI_MATCH(DMI_SYS_VENDOR, "Hewlett-Packard"),
1689 DMI_MATCH(DMI_PRODUCT_NAME, "HP Compaq nx6125"),
1690 },
1691 },
1692 {
1693 .callback = dmi_ignore_irq0_timer_override,
1694 .ident = "HP NX6325 laptop",
1695 .matches = {
1696 DMI_MATCH(DMI_SYS_VENDOR, "Hewlett-Packard"),
1697 DMI_MATCH(DMI_PRODUCT_NAME, "HP Compaq nx6325"),
1698 },
1699 },
1700 {
1701 .callback = dmi_ignore_irq0_timer_override,
1702 .ident = "HP 6715b laptop",
1703 .matches = {
1704 DMI_MATCH(DMI_SYS_VENDOR, "Hewlett-Packard"),
1705 DMI_MATCH(DMI_PRODUCT_NAME, "HP Compaq 6715b"),
1706 },
1707 },
1708 {}
1709 };
1710
1711 /*
1712 * acpi_boot_table_init() and acpi_boot_init()
1713 * called from setup_arch(), always.
1714 * 1. checksums all tables
1715 * 2. enumerates lapics
1716 * 3. enumerates io-apics
1717 *
1718 * acpi_table_init() is separate to allow reading SRAT without
1719 * other side effects.
1720 *
1721 * side effects of acpi_boot_init:
1722 * acpi_lapic = 1 if LAPIC found
1723 * acpi_ioapic = 1 if IOAPIC found
1724 * if (acpi_lapic && acpi_ioapic) smp_found_config = 1;
1725 * if acpi_blacklisted() acpi_disabled = 1;
1726 * acpi_irq_model=...
1727 * ...
1728 *
1729 * return value: (currently ignored)
1730 * 0: success
1731 * !0: failure
1732 */
1733
acpi_boot_table_init(void)1734 int __init acpi_boot_table_init(void)
1735 {
1736 int error;
1737
1738 dmi_check_system(acpi_dmi_table);
1739
1740 /*
1741 * If acpi_disabled, bail out
1742 * One exception: acpi=ht continues far enough to enumerate LAPICs
1743 */
1744 if (acpi_disabled && !acpi_ht)
1745 return 1;
1746
1747 /*
1748 * Initialize the ACPI boot-time table parser.
1749 */
1750 error = acpi_table_init();
1751 if (error) {
1752 disable_acpi();
1753 return error;
1754 }
1755
1756 acpi_table_parse(ACPI_SIG_BOOT, acpi_parse_sbf);
1757
1758 /*
1759 * blacklist may disable ACPI entirely
1760 */
1761 error = acpi_blacklisted();
1762 if (error) {
1763 if (acpi_force) {
1764 printk(KERN_WARNING PREFIX "acpi=force override\n");
1765 } else {
1766 printk(KERN_WARNING PREFIX "Disabling ACPI support\n");
1767 disable_acpi();
1768 return error;
1769 }
1770 }
1771
1772 return 0;
1773 }
1774
early_acpi_boot_init(void)1775 int __init early_acpi_boot_init(void)
1776 {
1777 /*
1778 * If acpi_disabled, bail out
1779 * One exception: acpi=ht continues far enough to enumerate LAPICs
1780 */
1781 if (acpi_disabled && !acpi_ht)
1782 return 1;
1783
1784 /*
1785 * Process the Multiple APIC Description Table (MADT), if present
1786 */
1787 early_acpi_process_madt();
1788
1789 return 0;
1790 }
1791
acpi_boot_init(void)1792 int __init acpi_boot_init(void)
1793 {
1794 /* those are executed after early-quirks are executed */
1795 dmi_check_system(acpi_dmi_table_late);
1796
1797 /*
1798 * If acpi_disabled, bail out
1799 * One exception: acpi=ht continues far enough to enumerate LAPICs
1800 */
1801 if (acpi_disabled && !acpi_ht)
1802 return 1;
1803
1804 acpi_table_parse(ACPI_SIG_BOOT, acpi_parse_sbf);
1805
1806 /*
1807 * set sci_int and PM timer address
1808 */
1809 acpi_table_parse(ACPI_SIG_FADT, acpi_parse_fadt);
1810
1811 /*
1812 * Process the Multiple APIC Description Table (MADT), if present
1813 */
1814 acpi_process_madt();
1815
1816 acpi_table_parse(ACPI_SIG_HPET, acpi_parse_hpet);
1817
1818 return 0;
1819 }
1820
parse_acpi(char * arg)1821 static int __init parse_acpi(char *arg)
1822 {
1823 if (!arg)
1824 return -EINVAL;
1825
1826 /* "acpi=off" disables both ACPI table parsing and interpreter */
1827 if (strcmp(arg, "off") == 0) {
1828 disable_acpi();
1829 }
1830 /* acpi=force to over-ride black-list */
1831 else if (strcmp(arg, "force") == 0) {
1832 acpi_force = 1;
1833 acpi_ht = 1;
1834 acpi_disabled = 0;
1835 }
1836 /* acpi=strict disables out-of-spec workarounds */
1837 else if (strcmp(arg, "strict") == 0) {
1838 acpi_strict = 1;
1839 }
1840 /* Limit ACPI just to boot-time to enable HT */
1841 else if (strcmp(arg, "ht") == 0) {
1842 if (!acpi_force)
1843 disable_acpi();
1844 acpi_ht = 1;
1845 }
1846 /* acpi=rsdt use RSDT instead of XSDT */
1847 else if (strcmp(arg, "rsdt") == 0) {
1848 acpi_rsdt_forced = 1;
1849 }
1850 /* "acpi=noirq" disables ACPI interrupt routing */
1851 else if (strcmp(arg, "noirq") == 0) {
1852 acpi_noirq_set();
1853 } else {
1854 /* Core will printk when we return error. */
1855 return -EINVAL;
1856 }
1857 return 0;
1858 }
1859 early_param("acpi", parse_acpi);
1860
1861 /* FIXME: Using pci= for an ACPI parameter is a travesty. */
parse_pci(char * arg)1862 static int __init parse_pci(char *arg)
1863 {
1864 if (arg && strcmp(arg, "noacpi") == 0)
1865 acpi_disable_pci();
1866 return 0;
1867 }
1868 early_param("pci", parse_pci);
1869
acpi_mps_check(void)1870 int __init acpi_mps_check(void)
1871 {
1872 #if defined(CONFIG_X86_LOCAL_APIC) && !defined(CONFIG_X86_MPPARSE)
1873 /* mptable code is not built-in*/
1874 if (acpi_disabled || acpi_noirq) {
1875 printk(KERN_WARNING "MPS support code is not built-in.\n"
1876 "Using acpi=off or acpi=noirq or pci=noacpi "
1877 "may have problem\n");
1878 return 1;
1879 }
1880 #endif
1881 return 0;
1882 }
1883
1884 #ifdef CONFIG_X86_IO_APIC
parse_acpi_skip_timer_override(char * arg)1885 static int __init parse_acpi_skip_timer_override(char *arg)
1886 {
1887 acpi_skip_timer_override = 1;
1888 return 0;
1889 }
1890 early_param("acpi_skip_timer_override", parse_acpi_skip_timer_override);
1891
parse_acpi_use_timer_override(char * arg)1892 static int __init parse_acpi_use_timer_override(char *arg)
1893 {
1894 acpi_use_timer_override = 1;
1895 return 0;
1896 }
1897 early_param("acpi_use_timer_override", parse_acpi_use_timer_override);
1898 #endif /* CONFIG_X86_IO_APIC */
1899
setup_acpi_sci(char * s)1900 static int __init setup_acpi_sci(char *s)
1901 {
1902 if (!s)
1903 return -EINVAL;
1904 if (!strcmp(s, "edge"))
1905 acpi_sci_flags = ACPI_MADT_TRIGGER_EDGE |
1906 (acpi_sci_flags & ~ACPI_MADT_TRIGGER_MASK);
1907 else if (!strcmp(s, "level"))
1908 acpi_sci_flags = ACPI_MADT_TRIGGER_LEVEL |
1909 (acpi_sci_flags & ~ACPI_MADT_TRIGGER_MASK);
1910 else if (!strcmp(s, "high"))
1911 acpi_sci_flags = ACPI_MADT_POLARITY_ACTIVE_HIGH |
1912 (acpi_sci_flags & ~ACPI_MADT_POLARITY_MASK);
1913 else if (!strcmp(s, "low"))
1914 acpi_sci_flags = ACPI_MADT_POLARITY_ACTIVE_LOW |
1915 (acpi_sci_flags & ~ACPI_MADT_POLARITY_MASK);
1916 else
1917 return -EINVAL;
1918 return 0;
1919 }
1920 early_param("acpi_sci", setup_acpi_sci);
1921
__acpi_acquire_global_lock(unsigned int * lock)1922 int __acpi_acquire_global_lock(unsigned int *lock)
1923 {
1924 unsigned int old, new, val;
1925 do {
1926 old = *lock;
1927 new = (((old & ~0x3) + 2) + ((old >> 1) & 0x1));
1928 val = cmpxchg(lock, old, new);
1929 } while (unlikely (val != old));
1930 return (new < 3) ? -1 : 0;
1931 }
1932
__acpi_release_global_lock(unsigned int * lock)1933 int __acpi_release_global_lock(unsigned int *lock)
1934 {
1935 unsigned int old, new, val;
1936 do {
1937 old = *lock;
1938 new = old & ~0x3;
1939 val = cmpxchg(lock, old, new);
1940 } while (unlikely (val != old));
1941 return old & 0x1;
1942 }
1943