1// SPDX-License-Identifier: GPL-2.0
2/*
3 * Intel Multiprocessor Specification 1.1 and 1.4
4 * compliant MP-table parsing routines.
5 *
6 * (c) 1995 Alan Cox, Building #3 <alan@lxorguk.ukuu.org.uk>
7 * (c) 1998, 1999, 2000, 2009 Ingo Molnar <mingo@redhat.com>
8 * (c) 2008 Alexey Starikovskiy <astarikovskiy@suse.de>
9 */
10
11#include <linux/mm.h>
12#include <linux/init.h>
13#include <linux/delay.h>
14#include <linux/memblock.h>
15#include <linux/kernel_stat.h>
16#include <linux/mc146818rtc.h>
17#include <linux/bitops.h>
18#include <linux/acpi.h>
19#include <linux/smp.h>
20#include <linux/pci.h>
21
22#include <asm/i8259.h>
23#include <asm/io_apic.h>
24#include <asm/acpi.h>
25#include <asm/irqdomain.h>
26#include <asm/mtrr.h>
27#include <asm/mpspec.h>
28#include <asm/proto.h>
29#include <asm/bios_ebda.h>
30#include <asm/e820/api.h>
31#include <asm/setup.h>
32#include <asm/smp.h>
33
34#include <asm/apic.h>
35/*
36 * Checksum an MP configuration block.
37 */
38
39static int __init mpf_checksum(unsigned char *mp, int len)
40{
41 int sum = 0;
42
43 while (len--)
44 sum += *mp++;
45
46 return sum & 0xFF;
47}
48
49static void __init MP_processor_info(struct mpc_cpu *m)
50{
51 char *bootup_cpu = "";
52
53 if (!(m->cpuflag & CPU_ENABLED)) {
54 disabled_cpus++;
55 return;
56 }
57
58 if (m->cpuflag & CPU_BOOTPROCESSOR)
59 bootup_cpu = " (Bootup-CPU)";
60
61 pr_info("Processor #%d%s\n", m->apicid, bootup_cpu);
62 generic_processor_info(apicid: m->apicid);
63}
64
65#ifdef CONFIG_X86_IO_APIC
66static void __init mpc_oem_bus_info(struct mpc_bus *m, char *str)
67{
68 memcpy(str, m->bustype, 6);
69 str[6] = 0;
70 apic_printk(APIC_VERBOSE, "Bus #%d is %s\n", m->busid, str);
71}
72
73static void __init MP_bus_info(struct mpc_bus *m)
74{
75 char str[7];
76
77 mpc_oem_bus_info(m, str);
78
79#if MAX_MP_BUSSES < 256
80 if (m->busid >= MAX_MP_BUSSES) {
81 pr_warn("MP table busid value (%d) for bustype %s is too large, max. supported is %d\n",
82 m->busid, str, MAX_MP_BUSSES - 1);
83 return;
84 }
85#endif
86
87 set_bit(nr: m->busid, addr: mp_bus_not_pci);
88 if (strncmp(str, BUSTYPE_ISA, sizeof(BUSTYPE_ISA) - 1) == 0) {
89#ifdef CONFIG_EISA
90 mp_bus_id_to_type[m->busid] = MP_BUS_ISA;
91#endif
92 } else if (strncmp(str, BUSTYPE_PCI, sizeof(BUSTYPE_PCI) - 1) == 0) {
93 clear_bit(nr: m->busid, addr: mp_bus_not_pci);
94#ifdef CONFIG_EISA
95 mp_bus_id_to_type[m->busid] = MP_BUS_PCI;
96 } else if (strncmp(str, BUSTYPE_EISA, sizeof(BUSTYPE_EISA) - 1) == 0) {
97 mp_bus_id_to_type[m->busid] = MP_BUS_EISA;
98#endif
99 } else
100 pr_warn("Unknown bustype %s - ignoring\n", str);
101}
102
103static void __init MP_ioapic_info(struct mpc_ioapic *m)
104{
105 struct ioapic_domain_cfg cfg = {
106 .type = IOAPIC_DOMAIN_LEGACY,
107 .ops = &mp_ioapic_irqdomain_ops,
108 };
109
110 if (m->flags & MPC_APIC_USABLE)
111 mp_register_ioapic(id: m->apicid, address: m->apicaddr, gsi_base: gsi_top, cfg: &cfg);
112}
113
114static void __init print_mp_irq_info(struct mpc_intsrc *mp_irq)
115{
116 apic_printk(APIC_VERBOSE,
117 "Int: type %d, pol %d, trig %d, bus %02x, IRQ %02x, APIC ID %x, APIC INT %02x\n",
118 mp_irq->irqtype, mp_irq->irqflag & 3,
119 (mp_irq->irqflag >> 2) & 3, mp_irq->srcbus,
120 mp_irq->srcbusirq, mp_irq->dstapic, mp_irq->dstirq);
121}
122
123#else /* CONFIG_X86_IO_APIC */
124static inline void __init MP_bus_info(struct mpc_bus *m) {}
125static inline void __init MP_ioapic_info(struct mpc_ioapic *m) {}
126#endif /* CONFIG_X86_IO_APIC */
127
128static void __init MP_lintsrc_info(struct mpc_lintsrc *m)
129{
130 apic_printk(APIC_VERBOSE,
131 "Lint: type %d, pol %d, trig %d, bus %02x, IRQ %02x, APIC ID %x, APIC LINT %02x\n",
132 m->irqtype, m->irqflag & 3, (m->irqflag >> 2) & 3, m->srcbusid,
133 m->srcbusirq, m->destapic, m->destapiclint);
134}
135
136/*
137 * Read/parse the MPC
138 */
139static int __init smp_check_mpc(struct mpc_table *mpc, char *oem, char *str)
140{
141
142 if (memcmp(p: mpc->signature, MPC_SIGNATURE, size: 4)) {
143 pr_err("MPTABLE: bad signature [%c%c%c%c]!\n",
144 mpc->signature[0], mpc->signature[1],
145 mpc->signature[2], mpc->signature[3]);
146 return 0;
147 }
148 if (mpf_checksum(mp: (unsigned char *)mpc, len: mpc->length)) {
149 pr_err("MPTABLE: checksum error!\n");
150 return 0;
151 }
152 if (mpc->spec != 0x01 && mpc->spec != 0x04) {
153 pr_err("MPTABLE: bad table version (%d)!!\n", mpc->spec);
154 return 0;
155 }
156 if (!mpc->lapic) {
157 pr_err("MPTABLE: null local APIC address!\n");
158 return 0;
159 }
160 memcpy(oem, mpc->oem, 8);
161 oem[8] = 0;
162 pr_info("MPTABLE: OEM ID: %s\n", oem);
163
164 memcpy(str, mpc->productid, 12);
165 str[12] = 0;
166
167 pr_info("MPTABLE: Product ID: %s\n", str);
168
169 pr_info("MPTABLE: APIC at: 0x%X\n", mpc->lapic);
170
171 return 1;
172}
173
174static void skip_entry(unsigned char **ptr, int *count, int size)
175{
176 *ptr += size;
177 *count += size;
178}
179
180static void __init smp_dump_mptable(struct mpc_table *mpc, unsigned char *mpt)
181{
182 pr_err("Your mptable is wrong, contact your HW vendor!\n");
183 pr_cont("type %x\n", *mpt);
184 print_hex_dump(KERN_ERR, prefix_str: " ", prefix_type: DUMP_PREFIX_ADDRESS, rowsize: 16,
185 groupsize: 1, buf: mpc, len: mpc->length, ascii: 1);
186}
187
188static int __init smp_read_mpc(struct mpc_table *mpc, unsigned early)
189{
190 char str[16];
191 char oem[10];
192
193 int count = sizeof(*mpc);
194 unsigned char *mpt = ((unsigned char *)mpc) + count;
195
196 if (!smp_check_mpc(mpc, oem, str))
197 return 0;
198
199 /* Initialize the lapic mapping */
200 if (!acpi_lapic)
201 register_lapic_address(address: mpc->lapic);
202
203 if (early)
204 return 1;
205
206 /* Now process the configuration blocks. */
207 while (count < mpc->length) {
208 switch (*mpt) {
209 case MP_PROCESSOR:
210 /* ACPI may have already provided this data */
211 if (!acpi_lapic)
212 MP_processor_info(m: (struct mpc_cpu *)mpt);
213 skip_entry(ptr: &mpt, count: &count, size: sizeof(struct mpc_cpu));
214 break;
215 case MP_BUS:
216 MP_bus_info(m: (struct mpc_bus *)mpt);
217 skip_entry(ptr: &mpt, count: &count, size: sizeof(struct mpc_bus));
218 break;
219 case MP_IOAPIC:
220 MP_ioapic_info(m: (struct mpc_ioapic *)mpt);
221 skip_entry(ptr: &mpt, count: &count, size: sizeof(struct mpc_ioapic));
222 break;
223 case MP_INTSRC:
224 mp_save_irq(m: (struct mpc_intsrc *)mpt);
225 skip_entry(ptr: &mpt, count: &count, size: sizeof(struct mpc_intsrc));
226 break;
227 case MP_LINTSRC:
228 MP_lintsrc_info(m: (struct mpc_lintsrc *)mpt);
229 skip_entry(ptr: &mpt, count: &count, size: sizeof(struct mpc_lintsrc));
230 break;
231 default:
232 /* wrong mptable */
233 smp_dump_mptable(mpc, mpt);
234 count = mpc->length;
235 break;
236 }
237 }
238
239 if (!num_processors)
240 pr_err("MPTABLE: no processors registered!\n");
241 return num_processors;
242}
243
244#ifdef CONFIG_X86_IO_APIC
245
246static int __init ELCR_trigger(unsigned int irq)
247{
248 unsigned int port;
249
250 port = PIC_ELCR1 + (irq >> 3);
251 return (inb(port) >> (irq & 7)) & 1;
252}
253
254static void __init construct_default_ioirq_mptable(int mpc_default_type)
255{
256 struct mpc_intsrc intsrc;
257 int i;
258 int ELCR_fallback = 0;
259
260 intsrc.type = MP_INTSRC;
261 intsrc.irqflag = MP_IRQTRIG_DEFAULT | MP_IRQPOL_DEFAULT;
262 intsrc.srcbus = 0;
263 intsrc.dstapic = mpc_ioapic_id(ioapic: 0);
264
265 intsrc.irqtype = mp_INT;
266
267 /*
268 * If true, we have an ISA/PCI system with no IRQ entries
269 * in the MP table. To prevent the PCI interrupts from being set up
270 * incorrectly, we try to use the ELCR. The sanity check to see if
271 * there is good ELCR data is very simple - IRQ0, 1, 2 and 13 can
272 * never be level sensitive, so we simply see if the ELCR agrees.
273 * If it does, we assume it's valid.
274 */
275 if (mpc_default_type == 5) {
276 pr_info("ISA/PCI bus type with no IRQ information... falling back to ELCR\n");
277
278 if (ELCR_trigger(irq: 0) || ELCR_trigger(irq: 1) || ELCR_trigger(irq: 2) ||
279 ELCR_trigger(irq: 13))
280 pr_err("ELCR contains invalid data... not using ELCR\n");
281 else {
282 pr_info("Using ELCR to identify PCI interrupts\n");
283 ELCR_fallback = 1;
284 }
285 }
286
287 for (i = 0; i < 16; i++) {
288 switch (mpc_default_type) {
289 case 2:
290 if (i == 0 || i == 13)
291 continue; /* IRQ0 & IRQ13 not connected */
292 fallthrough;
293 default:
294 if (i == 2)
295 continue; /* IRQ2 is never connected */
296 }
297
298 if (ELCR_fallback) {
299 /*
300 * If the ELCR indicates a level-sensitive interrupt, we
301 * copy that information over to the MP table in the
302 * irqflag field (level sensitive, active high polarity).
303 */
304 if (ELCR_trigger(irq: i)) {
305 intsrc.irqflag = MP_IRQTRIG_LEVEL |
306 MP_IRQPOL_ACTIVE_HIGH;
307 } else {
308 intsrc.irqflag = MP_IRQTRIG_DEFAULT |
309 MP_IRQPOL_DEFAULT;
310 }
311 }
312
313 intsrc.srcbusirq = i;
314 intsrc.dstirq = i ? i : 2; /* IRQ0 to INTIN2 */
315 mp_save_irq(m: &intsrc);
316 }
317
318 intsrc.irqtype = mp_ExtINT;
319 intsrc.srcbusirq = 0;
320 intsrc.dstirq = 0; /* 8259A to INTIN0 */
321 mp_save_irq(m: &intsrc);
322}
323
324
325static void __init construct_ioapic_table(int mpc_default_type)
326{
327 struct mpc_ioapic ioapic;
328 struct mpc_bus bus;
329
330 bus.type = MP_BUS;
331 bus.busid = 0;
332 switch (mpc_default_type) {
333 default:
334 pr_err("???\nUnknown standard configuration %d\n",
335 mpc_default_type);
336 fallthrough;
337 case 1:
338 case 5:
339 memcpy(bus.bustype, "ISA ", 6);
340 break;
341 case 2:
342 case 6:
343 case 3:
344 memcpy(bus.bustype, "EISA ", 6);
345 break;
346 }
347 MP_bus_info(m: &bus);
348 if (mpc_default_type > 4) {
349 bus.busid = 1;
350 memcpy(bus.bustype, "PCI ", 6);
351 MP_bus_info(m: &bus);
352 }
353
354 ioapic.type = MP_IOAPIC;
355 ioapic.apicid = 2;
356 ioapic.apicver = mpc_default_type > 4 ? 0x10 : 0x01;
357 ioapic.flags = MPC_APIC_USABLE;
358 ioapic.apicaddr = IO_APIC_DEFAULT_PHYS_BASE;
359 MP_ioapic_info(m: &ioapic);
360
361 /*
362 * We set up most of the low 16 IO-APIC pins according to MPS rules.
363 */
364 construct_default_ioirq_mptable(mpc_default_type);
365}
366#else
367static inline void __init construct_ioapic_table(int mpc_default_type) { }
368#endif
369
370static inline void __init construct_default_ISA_mptable(int mpc_default_type)
371{
372 struct mpc_cpu processor;
373 struct mpc_lintsrc lintsrc;
374 int linttypes[2] = { mp_ExtINT, mp_NMI };
375 int i;
376
377 /*
378 * 2 CPUs, numbered 0 & 1.
379 */
380 processor.type = MP_PROCESSOR;
381 /* Either an integrated APIC or a discrete 82489DX. */
382 processor.apicver = mpc_default_type > 4 ? 0x10 : 0x01;
383 processor.cpuflag = CPU_ENABLED;
384 processor.cpufeature = (boot_cpu_data.x86 << 8) |
385 (boot_cpu_data.x86_model << 4) | boot_cpu_data.x86_stepping;
386 processor.featureflag = boot_cpu_data.x86_capability[CPUID_1_EDX];
387 processor.reserved[0] = 0;
388 processor.reserved[1] = 0;
389 for (i = 0; i < 2; i++) {
390 processor.apicid = i;
391 MP_processor_info(m: &processor);
392 }
393
394 construct_ioapic_table(mpc_default_type);
395
396 lintsrc.type = MP_LINTSRC;
397 lintsrc.irqflag = MP_IRQTRIG_DEFAULT | MP_IRQPOL_DEFAULT;
398 lintsrc.srcbusid = 0;
399 lintsrc.srcbusirq = 0;
400 lintsrc.destapic = MP_APIC_ALL;
401 for (i = 0; i < 2; i++) {
402 lintsrc.irqtype = linttypes[i];
403 lintsrc.destapiclint = i;
404 MP_lintsrc_info(m: &lintsrc);
405 }
406}
407
408static unsigned long mpf_base;
409static bool mpf_found;
410
411static unsigned long __init get_mpc_size(unsigned long physptr)
412{
413 struct mpc_table *mpc;
414 unsigned long size;
415
416 mpc = early_memremap(phys_addr: physptr, PAGE_SIZE);
417 size = mpc->length;
418 early_memunmap(addr: mpc, PAGE_SIZE);
419 apic_printk(APIC_VERBOSE, " mpc: %lx-%lx\n", physptr, physptr + size);
420
421 return size;
422}
423
424static int __init check_physptr(struct mpf_intel *mpf, unsigned int early)
425{
426 struct mpc_table *mpc;
427 unsigned long size;
428
429 size = get_mpc_size(physptr: mpf->physptr);
430 mpc = early_memremap(phys_addr: mpf->physptr, size);
431
432 /*
433 * Read the physical hardware table. Anything here will
434 * override the defaults.
435 */
436 if (!smp_read_mpc(mpc, early)) {
437#ifdef CONFIG_X86_LOCAL_APIC
438 smp_found_config = 0;
439#endif
440 pr_err("BIOS bug, MP table errors detected!...\n");
441 pr_cont("... disabling SMP support. (tell your hw vendor)\n");
442 early_memunmap(addr: mpc, size);
443 return -1;
444 }
445 early_memunmap(addr: mpc, size);
446
447 if (early)
448 return -1;
449
450#ifdef CONFIG_X86_IO_APIC
451 /*
452 * If there are no explicit MP IRQ entries, then we are
453 * broken. We set up most of the low 16 IO-APIC pins to
454 * ISA defaults and hope it will work.
455 */
456 if (!mp_irq_entries) {
457 struct mpc_bus bus;
458
459 pr_err("BIOS bug, no explicit IRQ entries, using default mptable. (tell your hw vendor)\n");
460
461 bus.type = MP_BUS;
462 bus.busid = 0;
463 memcpy(bus.bustype, "ISA ", 6);
464 MP_bus_info(m: &bus);
465
466 construct_default_ioirq_mptable(mpc_default_type: 0);
467 }
468#endif
469
470 return 0;
471}
472
473/*
474 * Scan the memory blocks for an SMP configuration block.
475 */
476void __init default_get_smp_config(unsigned int early)
477{
478 struct mpf_intel *mpf;
479
480 if (!smp_found_config)
481 return;
482
483 if (!mpf_found)
484 return;
485
486 if (acpi_lapic && early)
487 return;
488
489 /*
490 * MPS doesn't support hyperthreading, aka only have
491 * thread 0 apic id in MPS table
492 */
493 if (acpi_lapic && acpi_ioapic)
494 return;
495
496 mpf = early_memremap(phys_addr: mpf_base, size: sizeof(*mpf));
497 if (!mpf) {
498 pr_err("MPTABLE: error mapping MP table\n");
499 return;
500 }
501
502 pr_info("Intel MultiProcessor Specification v1.%d\n",
503 mpf->specification);
504#if defined(CONFIG_X86_LOCAL_APIC) && defined(CONFIG_X86_32)
505 if (mpf->feature2 & (1 << 7)) {
506 pr_info(" IMCR and PIC compatibility mode.\n");
507 pic_mode = 1;
508 } else {
509 pr_info(" Virtual Wire compatibility mode.\n");
510 pic_mode = 0;
511 }
512#endif
513 /*
514 * Now see if we need to read further.
515 */
516 if (mpf->feature1) {
517 if (early) {
518 /* Local APIC has default address */
519 register_lapic_address(APIC_DEFAULT_PHYS_BASE);
520 goto out;
521 }
522
523 pr_info("Default MP configuration #%d\n", mpf->feature1);
524 construct_default_ISA_mptable(mpc_default_type: mpf->feature1);
525
526 } else if (mpf->physptr) {
527 if (check_physptr(mpf, early))
528 goto out;
529 } else
530 BUG();
531
532 if (!early)
533 pr_info("Processors: %d\n", num_processors);
534 /*
535 * Only use the first configuration found.
536 */
537out:
538 early_memunmap(addr: mpf, size: sizeof(*mpf));
539}
540
541static void __init smp_reserve_memory(struct mpf_intel *mpf)
542{
543 memblock_reserve(base: mpf->physptr, size: get_mpc_size(physptr: mpf->physptr));
544}
545
546static int __init smp_scan_config(unsigned long base, unsigned long length)
547{
548 unsigned int *bp;
549 struct mpf_intel *mpf;
550 int ret = 0;
551
552 apic_printk(APIC_VERBOSE, "Scan for SMP in [mem %#010lx-%#010lx]\n",
553 base, base + length - 1);
554 BUILD_BUG_ON(sizeof(*mpf) != 16);
555
556 while (length > 0) {
557 bp = early_memremap(phys_addr: base, size: length);
558 mpf = (struct mpf_intel *)bp;
559 if ((*bp == SMP_MAGIC_IDENT) &&
560 (mpf->length == 1) &&
561 !mpf_checksum(mp: (unsigned char *)bp, len: 16) &&
562 ((mpf->specification == 1)
563 || (mpf->specification == 4))) {
564#ifdef CONFIG_X86_LOCAL_APIC
565 smp_found_config = 1;
566#endif
567 mpf_base = base;
568 mpf_found = true;
569
570 pr_info("found SMP MP-table at [mem %#010lx-%#010lx]\n",
571 base, base + sizeof(*mpf) - 1);
572
573 memblock_reserve(base, size: sizeof(*mpf));
574 if (mpf->physptr)
575 smp_reserve_memory(mpf);
576
577 ret = 1;
578 }
579 early_memunmap(addr: bp, size: length);
580
581 if (ret)
582 break;
583
584 base += 16;
585 length -= 16;
586 }
587 return ret;
588}
589
590void __init default_find_smp_config(void)
591{
592 unsigned int address;
593
594 /*
595 * FIXME: Linux assumes you have 640K of base ram..
596 * this continues the error...
597 *
598 * 1) Scan the bottom 1K for a signature
599 * 2) Scan the top 1K of base RAM
600 * 3) Scan the 64K of bios
601 */
602 if (smp_scan_config(base: 0x0, length: 0x400) ||
603 smp_scan_config(base: 639 * 0x400, length: 0x400) ||
604 smp_scan_config(base: 0xF0000, length: 0x10000))
605 return;
606 /*
607 * If it is an SMP machine we should know now, unless the
608 * configuration is in an EISA bus machine with an
609 * extended bios data area.
610 *
611 * there is a real-mode segmented pointer pointing to the
612 * 4K EBDA area at 0x40E, calculate and scan it here.
613 *
614 * NOTE! There are Linux loaders that will corrupt the EBDA
615 * area, and as such this kind of SMP config may be less
616 * trustworthy, simply because the SMP table may have been
617 * stomped on during early boot. These loaders are buggy and
618 * should be fixed.
619 *
620 * MP1.4 SPEC states to only scan first 1K of 4K EBDA.
621 */
622
623 address = get_bios_ebda();
624 if (address)
625 smp_scan_config(base: address, length: 0x400);
626}
627
628#ifdef CONFIG_X86_IO_APIC
629static u8 __initdata irq_used[MAX_IRQ_SOURCES];
630
631static int __init get_MP_intsrc_index(struct mpc_intsrc *m)
632{
633 int i;
634
635 if (m->irqtype != mp_INT)
636 return 0;
637
638 if (m->irqflag != (MP_IRQTRIG_LEVEL | MP_IRQPOL_ACTIVE_LOW))
639 return 0;
640
641 /* not legacy */
642
643 for (i = 0; i < mp_irq_entries; i++) {
644 if (mp_irqs[i].irqtype != mp_INT)
645 continue;
646
647 if (mp_irqs[i].irqflag != (MP_IRQTRIG_LEVEL |
648 MP_IRQPOL_ACTIVE_LOW))
649 continue;
650
651 if (mp_irqs[i].srcbus != m->srcbus)
652 continue;
653 if (mp_irqs[i].srcbusirq != m->srcbusirq)
654 continue;
655 if (irq_used[i]) {
656 /* already claimed */
657 return -2;
658 }
659 irq_used[i] = 1;
660 return i;
661 }
662
663 /* not found */
664 return -1;
665}
666
667#define SPARE_SLOT_NUM 20
668
669static struct mpc_intsrc __initdata *m_spare[SPARE_SLOT_NUM];
670
671static void __init check_irq_src(struct mpc_intsrc *m, int *nr_m_spare)
672{
673 int i;
674
675 apic_printk(APIC_VERBOSE, "OLD ");
676 print_mp_irq_info(mp_irq: m);
677
678 i = get_MP_intsrc_index(m);
679 if (i > 0) {
680 memcpy(m, &mp_irqs[i], sizeof(*m));
681 apic_printk(APIC_VERBOSE, "NEW ");
682 print_mp_irq_info(mp_irq: &mp_irqs[i]);
683 return;
684 }
685 if (!i) {
686 /* legacy, do nothing */
687 return;
688 }
689 if (*nr_m_spare < SPARE_SLOT_NUM) {
690 /*
691 * not found (-1), or duplicated (-2) are invalid entries,
692 * we need to use the slot later
693 */
694 m_spare[*nr_m_spare] = m;
695 *nr_m_spare += 1;
696 }
697}
698
699static int __init
700check_slot(unsigned long mpc_new_phys, unsigned long mpc_new_length, int count)
701{
702 if (!mpc_new_phys || count <= mpc_new_length) {
703 WARN(1, "update_mptable: No spare slots (length: %x)\n", count);
704 return -1;
705 }
706
707 return 0;
708}
709#else /* CONFIG_X86_IO_APIC */
710static
711inline void __init check_irq_src(struct mpc_intsrc *m, int *nr_m_spare) {}
712#endif /* CONFIG_X86_IO_APIC */
713
714static int __init replace_intsrc_all(struct mpc_table *mpc,
715 unsigned long mpc_new_phys,
716 unsigned long mpc_new_length)
717{
718#ifdef CONFIG_X86_IO_APIC
719 int i;
720#endif
721 int count = sizeof(*mpc);
722 int nr_m_spare = 0;
723 unsigned char *mpt = ((unsigned char *)mpc) + count;
724
725 pr_info("mpc_length %x\n", mpc->length);
726 while (count < mpc->length) {
727 switch (*mpt) {
728 case MP_PROCESSOR:
729 skip_entry(ptr: &mpt, count: &count, size: sizeof(struct mpc_cpu));
730 break;
731 case MP_BUS:
732 skip_entry(ptr: &mpt, count: &count, size: sizeof(struct mpc_bus));
733 break;
734 case MP_IOAPIC:
735 skip_entry(ptr: &mpt, count: &count, size: sizeof(struct mpc_ioapic));
736 break;
737 case MP_INTSRC:
738 check_irq_src(m: (struct mpc_intsrc *)mpt, nr_m_spare: &nr_m_spare);
739 skip_entry(ptr: &mpt, count: &count, size: sizeof(struct mpc_intsrc));
740 break;
741 case MP_LINTSRC:
742 skip_entry(ptr: &mpt, count: &count, size: sizeof(struct mpc_lintsrc));
743 break;
744 default:
745 /* wrong mptable */
746 smp_dump_mptable(mpc, mpt);
747 goto out;
748 }
749 }
750
751#ifdef CONFIG_X86_IO_APIC
752 for (i = 0; i < mp_irq_entries; i++) {
753 if (irq_used[i])
754 continue;
755
756 if (mp_irqs[i].irqtype != mp_INT)
757 continue;
758
759 if (mp_irqs[i].irqflag != (MP_IRQTRIG_LEVEL |
760 MP_IRQPOL_ACTIVE_LOW))
761 continue;
762
763 if (nr_m_spare > 0) {
764 apic_printk(APIC_VERBOSE, "*NEW* found\n");
765 nr_m_spare--;
766 memcpy(m_spare[nr_m_spare], &mp_irqs[i], sizeof(mp_irqs[i]));
767 m_spare[nr_m_spare] = NULL;
768 } else {
769 struct mpc_intsrc *m = (struct mpc_intsrc *)mpt;
770 count += sizeof(struct mpc_intsrc);
771 if (check_slot(mpc_new_phys, mpc_new_length, count) < 0)
772 goto out;
773 memcpy(m, &mp_irqs[i], sizeof(*m));
774 mpc->length = count;
775 mpt += sizeof(struct mpc_intsrc);
776 }
777 print_mp_irq_info(mp_irq: &mp_irqs[i]);
778 }
779#endif
780out:
781 /* update checksum */
782 mpc->checksum = 0;
783 mpc->checksum -= mpf_checksum(mp: (unsigned char *)mpc, len: mpc->length);
784
785 return 0;
786}
787
788int enable_update_mptable;
789
790static int __init update_mptable_setup(char *str)
791{
792 enable_update_mptable = 1;
793#ifdef CONFIG_PCI
794 pci_routeirq = 1;
795#endif
796 return 0;
797}
798early_param("update_mptable", update_mptable_setup);
799
800static unsigned long __initdata mpc_new_phys;
801static unsigned long mpc_new_length __initdata = 4096;
802
803/* alloc_mptable or alloc_mptable=4k */
804static int __initdata alloc_mptable;
805static int __init parse_alloc_mptable_opt(char *p)
806{
807 enable_update_mptable = 1;
808#ifdef CONFIG_PCI
809 pci_routeirq = 1;
810#endif
811 alloc_mptable = 1;
812 if (!p)
813 return 0;
814 mpc_new_length = memparse(ptr: p, retptr: &p);
815 return 0;
816}
817early_param("alloc_mptable", parse_alloc_mptable_opt);
818
819void __init e820__memblock_alloc_reserved_mpc_new(void)
820{
821 if (enable_update_mptable && alloc_mptable)
822 mpc_new_phys = e820__memblock_alloc_reserved(size: mpc_new_length, align: 4);
823}
824
825static int __init update_mp_table(void)
826{
827 char str[16];
828 char oem[10];
829 struct mpf_intel *mpf;
830 struct mpc_table *mpc, *mpc_new;
831 unsigned long size;
832
833 if (!enable_update_mptable)
834 return 0;
835
836 if (!mpf_found)
837 return 0;
838
839 mpf = early_memremap(phys_addr: mpf_base, size: sizeof(*mpf));
840 if (!mpf) {
841 pr_err("MPTABLE: mpf early_memremap() failed\n");
842 return 0;
843 }
844
845 /*
846 * Now see if we need to go further.
847 */
848 if (mpf->feature1)
849 goto do_unmap_mpf;
850
851 if (!mpf->physptr)
852 goto do_unmap_mpf;
853
854 size = get_mpc_size(physptr: mpf->physptr);
855 mpc = early_memremap(phys_addr: mpf->physptr, size);
856 if (!mpc) {
857 pr_err("MPTABLE: mpc early_memremap() failed\n");
858 goto do_unmap_mpf;
859 }
860
861 if (!smp_check_mpc(mpc, oem, str))
862 goto do_unmap_mpc;
863
864 pr_info("mpf: %llx\n", (u64)mpf_base);
865 pr_info("physptr: %x\n", mpf->physptr);
866
867 if (mpc_new_phys && mpc->length > mpc_new_length) {
868 mpc_new_phys = 0;
869 pr_info("mpc_new_length is %ld, please use alloc_mptable=8k\n",
870 mpc_new_length);
871 }
872
873 if (!mpc_new_phys) {
874 unsigned char old, new;
875 /* check if we can change the position */
876 mpc->checksum = 0;
877 old = mpf_checksum(mp: (unsigned char *)mpc, len: mpc->length);
878 mpc->checksum = 0xff;
879 new = mpf_checksum(mp: (unsigned char *)mpc, len: mpc->length);
880 if (old == new) {
881 pr_info("mpc is readonly, please try alloc_mptable instead\n");
882 goto do_unmap_mpc;
883 }
884 pr_info("use in-position replacing\n");
885 } else {
886 mpc_new = early_memremap(phys_addr: mpc_new_phys, size: mpc_new_length);
887 if (!mpc_new) {
888 pr_err("MPTABLE: new mpc early_memremap() failed\n");
889 goto do_unmap_mpc;
890 }
891 mpf->physptr = mpc_new_phys;
892 memcpy(mpc_new, mpc, mpc->length);
893 early_memunmap(addr: mpc, size);
894 mpc = mpc_new;
895 size = mpc_new_length;
896 /* check if we can modify that */
897 if (mpc_new_phys - mpf->physptr) {
898 struct mpf_intel *mpf_new;
899 /* steal 16 bytes from [0, 1k) */
900 mpf_new = early_memremap(phys_addr: 0x400 - 16, size: sizeof(*mpf_new));
901 if (!mpf_new) {
902 pr_err("MPTABLE: new mpf early_memremap() failed\n");
903 goto do_unmap_mpc;
904 }
905 pr_info("mpf new: %x\n", 0x400 - 16);
906 memcpy(mpf_new, mpf, 16);
907 early_memunmap(addr: mpf, size: sizeof(*mpf));
908 mpf = mpf_new;
909 mpf->physptr = mpc_new_phys;
910 }
911 mpf->checksum = 0;
912 mpf->checksum -= mpf_checksum(mp: (unsigned char *)mpf, len: 16);
913 pr_info("physptr new: %x\n", mpf->physptr);
914 }
915
916 /*
917 * only replace the one with mp_INT and
918 * MP_IRQ_TRIGGER_LEVEL|MP_IRQ_POLARITY_LOW,
919 * already in mp_irqs , stored by ... and mp_config_acpi_gsi,
920 * may need pci=routeirq for all coverage
921 */
922 replace_intsrc_all(mpc, mpc_new_phys, mpc_new_length);
923
924do_unmap_mpc:
925 early_memunmap(addr: mpc, size);
926
927do_unmap_mpf:
928 early_memunmap(addr: mpf, size: sizeof(*mpf));
929
930 return 0;
931}
932
933late_initcall(update_mp_table);
934

source code of linux/arch/x86/kernel/mpparse.c