2 * Intel Multiprocessor Specification 1.1 and 1.4
3 * compliant MP-table parsing routines.
5 * (c) 1995 Alan Cox, Building #3 <alan@redhat.com>
6 * (c) 1998, 1999, 2000 Ingo Molnar <mingo@redhat.com>
9 * Erich Boleyn : MP v1.4 and additional changes.
10 * Alan Cox : Added EBDA scanning
11 * Ingo Molnar : various cleanups and rewrites
12 * Maciej W. Rozycki: Bits for default MP configurations
13 * Paul Diefenbaugh: Added full ACPI support
17 #include <linux/init.h>
18 #include <linux/delay.h>
19 #include <linux/bootmem.h>
20 #include <linux/kernel_stat.h>
21 #include <linux/mc146818rtc.h>
22 #include <linux/acpi.h>
23 #include <linux/module.h>
27 #include <asm/mpspec.h>
28 #include <asm/pgalloc.h>
29 #include <asm/io_apic.h>
30 #include <asm/proto.h>
33 /* Have we found an MP table */
37 * Various Linux-internal data structures created from the
40 DECLARE_BITMAP(mp_bus_not_pci, MAX_MP_BUSSES);
41 int mp_bus_id_to_pci_bus [MAX_MP_BUSSES] = { [0 ... MAX_MP_BUSSES-1] = -1 };
43 static int mp_current_pci_id = 0;
44 /* I/O APIC entries */
45 struct mpc_config_ioapic mp_ioapics[MAX_IO_APICS];
47 /* # of MP IRQ source entries */
48 struct mpc_config_intsrc mp_irqs[MAX_IRQ_SOURCES];
50 /* MP IRQ source entries */
54 unsigned long mp_lapic_addr = 0;
58 /* Processor that is doing the boot up */
59 unsigned int boot_cpu_id = -1U;
60 /* Internal processor count */
61 unsigned int num_processors __cpuinitdata = 0;
63 unsigned disabled_cpus __cpuinitdata;
65 /* Bitmask of physically existing CPUs */
66 physid_mask_t phys_cpu_present_map = PHYSID_MASK_NONE;
68 u8 bios_cpu_apicid[NR_CPUS] = { [0 ... NR_CPUS-1] = BAD_APICID };
72 * Intel MP BIOS table parsing routines:
76 * Checksum an MP configuration block.
79 static int __init mpf_checksum(unsigned char *mp, int len)
89 static void __cpuinit MP_processor_info (struct mpc_config_processor *m)
93 char *bootup_cpu = "";
95 if (!(m->mpc_cpuflag & CPU_ENABLED)) {
99 if (m->mpc_cpuflag & CPU_BOOTPROCESSOR) {
100 bootup_cpu = " (Bootup-CPU)";
101 boot_cpu_id = m->mpc_apicid;
104 printk(KERN_INFO "Processor #%d%s\n", m->mpc_apicid, bootup_cpu);
106 if (num_processors >= NR_CPUS) {
107 printk(KERN_WARNING "WARNING: NR_CPUS limit of %i reached."
108 " Processor ignored.\n", NR_CPUS);
113 cpus_complement(tmp_map, cpu_present_map);
114 cpu = first_cpu(tmp_map);
116 physid_set(m->mpc_apicid, phys_cpu_present_map);
117 if (m->mpc_cpuflag & CPU_BOOTPROCESSOR) {
119 * bios_cpu_apicid is required to have processors listed
120 * in same order as logical cpu numbers. Hence the first
121 * entry is BSP, and so on.
125 bios_cpu_apicid[cpu] = m->mpc_apicid;
126 x86_cpu_to_apicid[cpu] = m->mpc_apicid;
128 cpu_set(cpu, cpu_possible_map);
129 cpu_set(cpu, cpu_present_map);
132 static void __init MP_bus_info (struct mpc_config_bus *m)
136 memcpy(str, m->mpc_bustype, 6);
138 Dprintk("Bus #%d is %s\n", m->mpc_busid, str);
140 if (strncmp(str, "ISA", 3) == 0) {
141 set_bit(m->mpc_busid, mp_bus_not_pci);
142 } else if (strncmp(str, "PCI", 3) == 0) {
143 clear_bit(m->mpc_busid, mp_bus_not_pci);
144 mp_bus_id_to_pci_bus[m->mpc_busid] = mp_current_pci_id;
147 printk(KERN_ERR "Unknown bustype %s\n", str);
151 static int bad_ioapic(unsigned long address)
153 if (nr_ioapics >= MAX_IO_APICS) {
154 printk(KERN_ERR "ERROR: Max # of I/O APICs (%d) exceeded "
155 "(found %d)\n", MAX_IO_APICS, nr_ioapics);
156 panic("Recompile kernel with bigger MAX_IO_APICS!\n");
159 printk(KERN_ERR "WARNING: Bogus (zero) I/O APIC address"
160 " found in table, skipping!\n");
166 static void __init MP_ioapic_info (struct mpc_config_ioapic *m)
168 if (!(m->mpc_flags & MPC_APIC_USABLE))
171 printk("I/O APIC #%d at 0x%X.\n",
172 m->mpc_apicid, m->mpc_apicaddr);
174 if (bad_ioapic(m->mpc_apicaddr))
177 mp_ioapics[nr_ioapics] = *m;
181 static void __init MP_intsrc_info (struct mpc_config_intsrc *m)
183 mp_irqs [mp_irq_entries] = *m;
184 Dprintk("Int: type %d, pol %d, trig %d, bus %d,"
185 " IRQ %02x, APIC ID %x, APIC INT %02x\n",
186 m->mpc_irqtype, m->mpc_irqflag & 3,
187 (m->mpc_irqflag >> 2) & 3, m->mpc_srcbus,
188 m->mpc_srcbusirq, m->mpc_dstapic, m->mpc_dstirq);
189 if (++mp_irq_entries >= MAX_IRQ_SOURCES)
190 panic("Max # of irq sources exceeded!!\n");
193 static void __init MP_lintsrc_info (struct mpc_config_lintsrc *m)
195 Dprintk("Lint: type %d, pol %d, trig %d, bus %d,"
196 " IRQ %02x, APIC ID %x, APIC LINT %02x\n",
197 m->mpc_irqtype, m->mpc_irqflag & 3,
198 (m->mpc_irqflag >> 2) &3, m->mpc_srcbusid,
199 m->mpc_srcbusirq, m->mpc_destapic, m->mpc_destapiclint);
206 static int __init smp_read_mpc(struct mp_config_table *mpc)
209 int count=sizeof(*mpc);
210 unsigned char *mpt=((unsigned char *)mpc)+count;
212 if (memcmp(mpc->mpc_signature,MPC_SIGNATURE,4)) {
213 printk("MPTABLE: bad signature [%c%c%c%c]!\n",
214 mpc->mpc_signature[0],
215 mpc->mpc_signature[1],
216 mpc->mpc_signature[2],
217 mpc->mpc_signature[3]);
220 if (mpf_checksum((unsigned char *)mpc,mpc->mpc_length)) {
221 printk("MPTABLE: checksum error!\n");
224 if (mpc->mpc_spec!=0x01 && mpc->mpc_spec!=0x04) {
225 printk(KERN_ERR "MPTABLE: bad table version (%d)!!\n",
229 if (!mpc->mpc_lapic) {
230 printk(KERN_ERR "MPTABLE: null local APIC address!\n");
233 memcpy(str,mpc->mpc_oem,8);
235 printk(KERN_INFO "MPTABLE: OEM ID: %s ",str);
237 memcpy(str,mpc->mpc_productid,12);
239 printk("MPTABLE: Product ID: %s ",str);
241 printk("MPTABLE: APIC at: 0x%X\n",mpc->mpc_lapic);
243 /* save the local APIC address, it might be non-default */
245 mp_lapic_addr = mpc->mpc_lapic;
248 * Now process the configuration blocks.
250 while (count < mpc->mpc_length) {
254 struct mpc_config_processor *m=
255 (struct mpc_config_processor *)mpt;
257 MP_processor_info(m);
264 struct mpc_config_bus *m=
265 (struct mpc_config_bus *)mpt;
273 struct mpc_config_ioapic *m=
274 (struct mpc_config_ioapic *)mpt;
282 struct mpc_config_intsrc *m=
283 (struct mpc_config_intsrc *)mpt;
292 struct mpc_config_lintsrc *m=
293 (struct mpc_config_lintsrc *)mpt;
301 setup_apic_routing();
303 printk(KERN_ERR "MPTABLE: no processors registered!\n");
304 return num_processors;
307 static int __init ELCR_trigger(unsigned int irq)
311 port = 0x4d0 + (irq >> 3);
312 return (inb(port) >> (irq & 7)) & 1;
315 static void __init construct_default_ioirq_mptable(int mpc_default_type)
317 struct mpc_config_intsrc intsrc;
319 int ELCR_fallback = 0;
321 intsrc.mpc_type = MP_INTSRC;
322 intsrc.mpc_irqflag = 0; /* conforming */
323 intsrc.mpc_srcbus = 0;
324 intsrc.mpc_dstapic = mp_ioapics[0].mpc_apicid;
326 intsrc.mpc_irqtype = mp_INT;
329 * If true, we have an ISA/PCI system with no IRQ entries
330 * in the MP table. To prevent the PCI interrupts from being set up
331 * incorrectly, we try to use the ELCR. The sanity check to see if
332 * there is good ELCR data is very simple - IRQ0, 1, 2 and 13 can
333 * never be level sensitive, so we simply see if the ELCR agrees.
334 * If it does, we assume it's valid.
336 if (mpc_default_type == 5) {
337 printk(KERN_INFO "ISA/PCI bus type with no IRQ information... falling back to ELCR\n");
339 if (ELCR_trigger(0) || ELCR_trigger(1) || ELCR_trigger(2) || ELCR_trigger(13))
340 printk(KERN_ERR "ELCR contains invalid data... not using ELCR\n");
342 printk(KERN_INFO "Using ELCR to identify PCI interrupts\n");
347 for (i = 0; i < 16; i++) {
348 switch (mpc_default_type) {
350 if (i == 0 || i == 13)
351 continue; /* IRQ0 & IRQ13 not connected */
355 continue; /* IRQ2 is never connected */
360 * If the ELCR indicates a level-sensitive interrupt, we
361 * copy that information over to the MP table in the
362 * irqflag field (level sensitive, active high polarity).
365 intsrc.mpc_irqflag = 13;
367 intsrc.mpc_irqflag = 0;
370 intsrc.mpc_srcbusirq = i;
371 intsrc.mpc_dstirq = i ? i : 2; /* IRQ0 to INTIN2 */
372 MP_intsrc_info(&intsrc);
375 intsrc.mpc_irqtype = mp_ExtINT;
376 intsrc.mpc_srcbusirq = 0;
377 intsrc.mpc_dstirq = 0; /* 8259A to INTIN0 */
378 MP_intsrc_info(&intsrc);
381 static inline void __init construct_default_ISA_mptable(int mpc_default_type)
383 struct mpc_config_processor processor;
384 struct mpc_config_bus bus;
385 struct mpc_config_ioapic ioapic;
386 struct mpc_config_lintsrc lintsrc;
387 int linttypes[2] = { mp_ExtINT, mp_NMI };
391 * local APIC has default address
393 mp_lapic_addr = APIC_DEFAULT_PHYS_BASE;
396 * 2 CPUs, numbered 0 & 1.
398 processor.mpc_type = MP_PROCESSOR;
399 processor.mpc_apicver = 0;
400 processor.mpc_cpuflag = CPU_ENABLED;
401 processor.mpc_cpufeature = 0;
402 processor.mpc_featureflag = 0;
403 processor.mpc_reserved[0] = 0;
404 processor.mpc_reserved[1] = 0;
405 for (i = 0; i < 2; i++) {
406 processor.mpc_apicid = i;
407 MP_processor_info(&processor);
410 bus.mpc_type = MP_BUS;
412 switch (mpc_default_type) {
414 printk(KERN_ERR "???\nUnknown standard configuration %d\n",
419 memcpy(bus.mpc_bustype, "ISA ", 6);
423 if (mpc_default_type > 4) {
425 memcpy(bus.mpc_bustype, "PCI ", 6);
429 ioapic.mpc_type = MP_IOAPIC;
430 ioapic.mpc_apicid = 2;
431 ioapic.mpc_apicver = 0;
432 ioapic.mpc_flags = MPC_APIC_USABLE;
433 ioapic.mpc_apicaddr = 0xFEC00000;
434 MP_ioapic_info(&ioapic);
437 * We set up most of the low 16 IO-APIC pins according to MPS rules.
439 construct_default_ioirq_mptable(mpc_default_type);
441 lintsrc.mpc_type = MP_LINTSRC;
442 lintsrc.mpc_irqflag = 0; /* conforming */
443 lintsrc.mpc_srcbusid = 0;
444 lintsrc.mpc_srcbusirq = 0;
445 lintsrc.mpc_destapic = MP_APIC_ALL;
446 for (i = 0; i < 2; i++) {
447 lintsrc.mpc_irqtype = linttypes[i];
448 lintsrc.mpc_destapiclint = i;
449 MP_lintsrc_info(&lintsrc);
453 static struct intel_mp_floating *mpf_found;
456 * Scan the memory blocks for an SMP configuration block.
458 void __init get_smp_config (void)
460 struct intel_mp_floating *mpf = mpf_found;
463 * ACPI supports both logical (e.g. Hyper-Threading) and physical
464 * processors, where MPS only supports physical.
466 if (acpi_lapic && acpi_ioapic) {
467 printk(KERN_INFO "Using ACPI (MADT) for SMP configuration information\n");
471 printk(KERN_INFO "Using ACPI for processor (LAPIC) configuration information\n");
473 printk("Intel MultiProcessor Specification v1.%d\n", mpf->mpf_specification);
476 * Now see if we need to read further.
478 if (mpf->mpf_feature1 != 0) {
480 printk(KERN_INFO "Default MP configuration #%d\n", mpf->mpf_feature1);
481 construct_default_ISA_mptable(mpf->mpf_feature1);
483 } else if (mpf->mpf_physptr) {
486 * Read the physical hardware table. Anything here will
487 * override the defaults.
489 if (!smp_read_mpc(phys_to_virt(mpf->mpf_physptr))) {
490 smp_found_config = 0;
491 printk(KERN_ERR "BIOS bug, MP table errors detected!...\n");
492 printk(KERN_ERR "... disabling SMP support. (tell your hw vendor)\n");
496 * If there are no explicit MP IRQ entries, then we are
497 * broken. We set up most of the low 16 IO-APIC pins to
498 * ISA defaults and hope it will work.
500 if (!mp_irq_entries) {
501 struct mpc_config_bus bus;
503 printk(KERN_ERR "BIOS bug, no explicit IRQ entries, using default mptable. (tell your hw vendor)\n");
505 bus.mpc_type = MP_BUS;
507 memcpy(bus.mpc_bustype, "ISA ", 6);
510 construct_default_ioirq_mptable(0);
516 printk(KERN_INFO "Processors: %d\n", num_processors);
518 * Only use the first configuration found.
522 static int __init smp_scan_config (unsigned long base, unsigned long length)
524 extern void __bad_mpf_size(void);
525 unsigned int *bp = phys_to_virt(base);
526 struct intel_mp_floating *mpf;
528 Dprintk("Scan SMP from %p for %ld bytes.\n", bp,length);
529 if (sizeof(*mpf) != 16)
533 mpf = (struct intel_mp_floating *)bp;
534 if ((*bp == SMP_MAGIC_IDENT) &&
535 (mpf->mpf_length == 1) &&
536 !mpf_checksum((unsigned char *)bp, 16) &&
537 ((mpf->mpf_specification == 1)
538 || (mpf->mpf_specification == 4)) ) {
540 smp_found_config = 1;
541 reserve_bootmem_generic(virt_to_phys(mpf), PAGE_SIZE);
542 if (mpf->mpf_physptr)
543 reserve_bootmem_generic(mpf->mpf_physptr, PAGE_SIZE);
553 void __init find_smp_config(void)
555 unsigned int address;
558 * FIXME: Linux assumes you have 640K of base ram..
559 * this continues the error...
561 * 1) Scan the bottom 1K for a signature
562 * 2) Scan the top 1K of base RAM
563 * 3) Scan the 64K of bios
565 if (smp_scan_config(0x0,0x400) ||
566 smp_scan_config(639*0x400,0x400) ||
567 smp_scan_config(0xF0000,0x10000))
570 * If it is an SMP machine we should know now.
572 * there is a real-mode segmented pointer pointing to the
573 * 4K EBDA area at 0x40E, calculate and scan it here.
575 * NOTE! There are Linux loaders that will corrupt the EBDA
576 * area, and as such this kind of SMP config may be less
577 * trustworthy, simply because the SMP table may have been
578 * stomped on during early boot. These loaders are buggy and
582 address = *(unsigned short *)phys_to_virt(0x40E);
584 if (smp_scan_config(address, 0x1000))
587 /* If we have come this far, we did not find an MP table */
588 printk(KERN_INFO "No mptable found.\n");
591 /* --------------------------------------------------------------------------
592 ACPI-based MP Configuration
593 -------------------------------------------------------------------------- */
597 void __init mp_register_lapic_address(u64 address)
599 mp_lapic_addr = (unsigned long) address;
600 set_fixmap_nocache(FIX_APIC_BASE, mp_lapic_addr);
601 if (boot_cpu_id == -1U)
602 boot_cpu_id = GET_APIC_ID(apic_read(APIC_ID));
605 void __cpuinit mp_register_lapic (u8 id, u8 enabled)
607 struct mpc_config_processor processor;
610 if (id == boot_cpu_id)
613 processor.mpc_type = MP_PROCESSOR;
614 processor.mpc_apicid = id;
615 processor.mpc_apicver = 0;
616 processor.mpc_cpuflag = (enabled ? CPU_ENABLED : 0);
617 processor.mpc_cpuflag |= (boot_cpu ? CPU_BOOTPROCESSOR : 0);
618 processor.mpc_cpufeature = 0;
619 processor.mpc_featureflag = 0;
620 processor.mpc_reserved[0] = 0;
621 processor.mpc_reserved[1] = 0;
623 MP_processor_info(&processor);
627 #define MP_MAX_IOAPIC_PIN 127
629 static struct mp_ioapic_routing {
633 u32 pin_programmed[4];
634 } mp_ioapic_routing[MAX_IO_APICS];
636 static int mp_find_ioapic(int gsi)
640 /* Find the IOAPIC that manages this GSI. */
641 for (i = 0; i < nr_ioapics; i++) {
642 if ((gsi >= mp_ioapic_routing[i].gsi_start)
643 && (gsi <= mp_ioapic_routing[i].gsi_end))
647 printk(KERN_ERR "ERROR: Unable to locate IOAPIC for GSI %d\n", gsi);
651 static u8 uniq_ioapic_id(u8 id)
654 DECLARE_BITMAP(used, 256);
655 bitmap_zero(used, 256);
656 for (i = 0; i < nr_ioapics; i++) {
657 struct mpc_config_ioapic *ia = &mp_ioapics[i];
658 __set_bit(ia->mpc_apicid, used);
660 if (!test_bit(id, used))
662 return find_first_zero_bit(used, 256);
665 void __init mp_register_ioapic(u8 id, u32 address, u32 gsi_base)
669 if (bad_ioapic(address))
674 mp_ioapics[idx].mpc_type = MP_IOAPIC;
675 mp_ioapics[idx].mpc_flags = MPC_APIC_USABLE;
676 mp_ioapics[idx].mpc_apicaddr = address;
678 set_fixmap_nocache(FIX_IO_APIC_BASE_0 + idx, address);
679 mp_ioapics[idx].mpc_apicid = uniq_ioapic_id(id);
680 mp_ioapics[idx].mpc_apicver = 0;
683 * Build basic IRQ lookup table to facilitate gsi->io_apic lookups
684 * and to prevent reprogramming of IOAPIC pins (PCI IRQs).
686 mp_ioapic_routing[idx].apic_id = mp_ioapics[idx].mpc_apicid;
687 mp_ioapic_routing[idx].gsi_start = gsi_base;
688 mp_ioapic_routing[idx].gsi_end = gsi_base +
689 io_apic_get_redir_entries(idx);
691 printk(KERN_INFO "IOAPIC[%d]: apic_id %d, address 0x%x, "
692 "GSI %d-%d\n", idx, mp_ioapics[idx].mpc_apicid,
693 mp_ioapics[idx].mpc_apicaddr,
694 mp_ioapic_routing[idx].gsi_start,
695 mp_ioapic_routing[idx].gsi_end);
701 mp_override_legacy_irq(u8 bus_irq, u8 polarity, u8 trigger, u32 gsi)
703 struct mpc_config_intsrc intsrc;
708 * Convert 'gsi' to 'ioapic.pin'.
710 ioapic = mp_find_ioapic(gsi);
713 pin = gsi - mp_ioapic_routing[ioapic].gsi_start;
716 * TBD: This check is for faulty timer entries, where the override
717 * erroneously sets the trigger to level, resulting in a HUGE
718 * increase of timer interrupts!
720 if ((bus_irq == 0) && (trigger == 3))
723 intsrc.mpc_type = MP_INTSRC;
724 intsrc.mpc_irqtype = mp_INT;
725 intsrc.mpc_irqflag = (trigger << 2) | polarity;
726 intsrc.mpc_srcbus = MP_ISA_BUS;
727 intsrc.mpc_srcbusirq = bus_irq; /* IRQ */
728 intsrc.mpc_dstapic = mp_ioapics[ioapic].mpc_apicid; /* APIC ID */
729 intsrc.mpc_dstirq = pin; /* INTIN# */
731 Dprintk("Int: type %d, pol %d, trig %d, bus %d, irq %d, %d-%d\n",
732 intsrc.mpc_irqtype, intsrc.mpc_irqflag & 3,
733 (intsrc.mpc_irqflag >> 2) & 3, intsrc.mpc_srcbus,
734 intsrc.mpc_srcbusirq, intsrc.mpc_dstapic, intsrc.mpc_dstirq);
736 mp_irqs[mp_irq_entries] = intsrc;
737 if (++mp_irq_entries == MAX_IRQ_SOURCES)
738 panic("Max # of irq sources exceeded!\n");
741 void __init mp_config_acpi_legacy_irqs(void)
743 struct mpc_config_intsrc intsrc;
748 * Fabricate the legacy ISA bus (bus #31).
750 set_bit(MP_ISA_BUS, mp_bus_not_pci);
753 * Locate the IOAPIC that manages the ISA IRQs (0-15).
755 ioapic = mp_find_ioapic(0);
759 intsrc.mpc_type = MP_INTSRC;
760 intsrc.mpc_irqflag = 0; /* Conforming */
761 intsrc.mpc_srcbus = MP_ISA_BUS;
762 intsrc.mpc_dstapic = mp_ioapics[ioapic].mpc_apicid;
765 * Use the default configuration for the IRQs 0-15. Unless
766 * overridden by (MADT) interrupt source override entries.
768 for (i = 0; i < 16; i++) {
771 for (idx = 0; idx < mp_irq_entries; idx++) {
772 struct mpc_config_intsrc *irq = mp_irqs + idx;
774 /* Do we already have a mapping for this ISA IRQ? */
775 if (irq->mpc_srcbus == MP_ISA_BUS && irq->mpc_srcbusirq == i)
778 /* Do we already have a mapping for this IOAPIC pin */
779 if ((irq->mpc_dstapic == intsrc.mpc_dstapic) &&
780 (irq->mpc_dstirq == i))
784 if (idx != mp_irq_entries) {
785 printk(KERN_DEBUG "ACPI: IRQ%d used by override.\n", i);
786 continue; /* IRQ already used */
789 intsrc.mpc_irqtype = mp_INT;
790 intsrc.mpc_srcbusirq = i; /* Identity mapped */
791 intsrc.mpc_dstirq = i;
793 Dprintk("Int: type %d, pol %d, trig %d, bus %d, irq %d, "
794 "%d-%d\n", intsrc.mpc_irqtype, intsrc.mpc_irqflag & 3,
795 (intsrc.mpc_irqflag >> 2) & 3, intsrc.mpc_srcbus,
796 intsrc.mpc_srcbusirq, intsrc.mpc_dstapic,
799 mp_irqs[mp_irq_entries] = intsrc;
800 if (++mp_irq_entries == MAX_IRQ_SOURCES)
801 panic("Max # of irq sources exceeded!\n");
805 int mp_register_gsi(u32 gsi, int triggering, int polarity)
811 if (acpi_irq_model != ACPI_IRQ_MODEL_IOAPIC)
814 /* Don't set up the ACPI SCI because it's already set up */
815 if (acpi_gbl_FADT.sci_interrupt == gsi)
818 ioapic = mp_find_ioapic(gsi);
820 printk(KERN_WARNING "No IOAPIC for GSI %u\n", gsi);
824 ioapic_pin = gsi - mp_ioapic_routing[ioapic].gsi_start;
827 * Avoid pin reprogramming. PRTs typically include entries
828 * with redundant pin->gsi mappings (but unique PCI devices);
829 * we only program the IOAPIC on the first.
831 bit = ioapic_pin % 32;
832 idx = (ioapic_pin < 32) ? 0 : (ioapic_pin / 32);
834 printk(KERN_ERR "Invalid reference to IOAPIC pin "
835 "%d-%d\n", mp_ioapic_routing[ioapic].apic_id,
839 if ((1<<bit) & mp_ioapic_routing[ioapic].pin_programmed[idx]) {
840 Dprintk(KERN_DEBUG "Pin %d-%d already programmed\n",
841 mp_ioapic_routing[ioapic].apic_id, ioapic_pin);
845 mp_ioapic_routing[ioapic].pin_programmed[idx] |= (1<<bit);
847 io_apic_set_pci_routing(ioapic, ioapic_pin, gsi,
848 triggering == ACPI_EDGE_SENSITIVE ? 0 : 1,
849 polarity == ACPI_ACTIVE_HIGH ? 0 : 1);
852 #endif /*CONFIG_ACPI*/