/* * Intel Multiprocessor Specification 1.1 and 1.4 * compliant MP-table parsing routines. * * (c) 1995 Alan Cox, Building #3 * (c) 1998, 1999, 2000 Ingo Molnar * * Fixes * Erich Boleyn : MP v1.4 and additional changes. * Alan Cox : Added EBDA scanning * Ingo Molnar : various cleanups and rewrites * Maciej W. Rozycki: Bits for default MP configurations * Paul Diefenbaugh: Added full ACPI support */ #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include /* Have we found an MP table */ int smp_found_config; unsigned int __initdata maxcpus = NR_CPUS; int acpi_found_madt; /* * Various Linux-internal data structures created from the * MP-table. */ DECLARE_BITMAP(mp_bus_not_pci, MAX_MP_BUSSES); int mp_bus_id_to_pci_bus [MAX_MP_BUSSES] = { [0 ... MAX_MP_BUSSES-1] = -1 }; static int mp_current_pci_id = 0; /* I/O APIC entries */ struct mpc_config_ioapic mp_ioapics[MAX_IO_APICS]; /* # of MP IRQ source entries */ struct mpc_config_intsrc mp_irqs[MAX_IRQ_SOURCES]; /* MP IRQ source entries */ int mp_irq_entries; int nr_ioapics; unsigned long mp_lapic_addr = 0; /* Processor that is doing the boot up */ unsigned int boot_cpu_id = -1U; /* Internal processor count */ unsigned int num_processors __initdata = 0; unsigned disabled_cpus __initdata; /* Bitmask of physically existing CPUs */ physid_mask_t phys_cpu_present_map = PHYSID_MASK_NONE; u8 bios_cpu_apicid[NR_CPUS] = { [0 ... NR_CPUS-1] = BAD_APICID }; /* * Intel MP BIOS table parsing routines: */ /* * Checksum an MP configuration block. */ static int __init mpf_checksum(unsigned char *mp, int len) { int sum = 0; while (len--) sum += *mp++; return sum & 0xFF; } static void __cpuinit MP_processor_info (struct mpc_config_processor *m) { int cpu; cpumask_t tmp_map; char *bootup_cpu = ""; if (!(m->mpc_cpuflag & CPU_ENABLED)) { disabled_cpus++; return; } if (m->mpc_cpuflag & CPU_BOOTPROCESSOR) { bootup_cpu = " (Bootup-CPU)"; boot_cpu_id = m->mpc_apicid; } printk(KERN_INFO "Processor #%d%s\n", m->mpc_apicid, bootup_cpu); if (num_processors >= NR_CPUS) { printk(KERN_WARNING "WARNING: NR_CPUS limit of %i reached." " Processor ignored.\n", NR_CPUS); return; } num_processors++; cpus_complement(tmp_map, cpu_present_map); cpu = first_cpu(tmp_map); #if MAX_APICS < 255 if ((int)m->mpc_apicid > MAX_APICS) { printk(KERN_ERR "Processor #%d INVALID. (Max ID: %d).\n", m->mpc_apicid, MAX_APICS); return; } #endif physid_set(m->mpc_apicid, phys_cpu_present_map); if (m->mpc_cpuflag & CPU_BOOTPROCESSOR) { /* * bios_cpu_apicid is required to have processors listed * in same order as logical cpu numbers. Hence the first * entry is BSP, and so on. */ cpu = 0; } bios_cpu_apicid[cpu] = m->mpc_apicid; x86_cpu_to_apicid[cpu] = m->mpc_apicid; cpu_set(cpu, cpu_possible_map); cpu_set(cpu, cpu_present_map); } static void __init MP_bus_info (struct mpc_config_bus *m) { char str[7]; memcpy(str, m->mpc_bustype, 6); str[6] = 0; Dprintk("Bus #%d is %s\n", m->mpc_busid, str); if (strncmp(str, "ISA", 3) == 0) { set_bit(m->mpc_busid, mp_bus_not_pci); } else if (strncmp(str, "PCI", 3) == 0) { clear_bit(m->mpc_busid, mp_bus_not_pci); mp_bus_id_to_pci_bus[m->mpc_busid] = mp_current_pci_id; mp_current_pci_id++; } else { printk(KERN_ERR "Unknown bustype %s\n", str); } } static void __init MP_ioapic_info (struct mpc_config_ioapic *m) { if (!(m->mpc_flags & MPC_APIC_USABLE)) return; printk("I/O APIC #%d at 0x%X.\n", m->mpc_apicid, m->mpc_apicaddr); if (nr_ioapics >= MAX_IO_APICS) { printk(KERN_ERR "Max # of I/O APICs (%d) exceeded (found %d).\n", MAX_IO_APICS, nr_ioapics); panic("Recompile kernel with bigger MAX_IO_APICS!.\n"); } if (!m->mpc_apicaddr) { printk(KERN_ERR "WARNING: bogus zero I/O APIC address" " found in MP table, skipping!\n"); return; } mp_ioapics[nr_ioapics] = *m; nr_ioapics++; } static void __init MP_intsrc_info (struct mpc_config_intsrc *m) { mp_irqs [mp_irq_entries] = *m; Dprintk("Int: type %d, pol %d, trig %d, bus %d," " IRQ %02x, APIC ID %x, APIC INT %02x\n", m->mpc_irqtype, m->mpc_irqflag & 3, (m->mpc_irqflag >> 2) & 3, m->mpc_srcbus, m->mpc_srcbusirq, m->mpc_dstapic, m->mpc_dstirq); if (++mp_irq_entries >= MAX_IRQ_SOURCES) panic("Max # of irq sources exceeded!!\n"); } static void __init MP_lintsrc_info (struct mpc_config_lintsrc *m) { Dprintk("Lint: type %d, pol %d, trig %d, bus %d," " IRQ %02x, APIC ID %x, APIC LINT %02x\n", m->mpc_irqtype, m->mpc_irqflag & 3, (m->mpc_irqflag >> 2) &3, m->mpc_srcbusid, m->mpc_srcbusirq, m->mpc_destapic, m->mpc_destapiclint); } /* * Read/parse the MPC */ static int __init smp_read_mpc(struct mp_config_table *mpc) { char str[16]; int count=sizeof(*mpc); unsigned char *mpt=((unsigned char *)mpc)+count; if (memcmp(mpc->mpc_signature,MPC_SIGNATURE,4)) { printk("SMP mptable: bad signature [%c%c%c%c]!\n", mpc->mpc_signature[0], mpc->mpc_signature[1], mpc->mpc_signature[2], mpc->mpc_signature[3]); return 0; } if (mpf_checksum((unsigned char *)mpc,mpc->mpc_length)) { printk("SMP mptable: checksum error!\n"); return 0; } if (mpc->mpc_spec!=0x01 && mpc->mpc_spec!=0x04) { printk(KERN_ERR "SMP mptable: bad table version (%d)!!\n", mpc->mpc_spec); return 0; } if (!mpc->mpc_lapic) { printk(KERN_ERR "SMP mptable: null local APIC address!\n"); return 0; } memcpy(str,mpc->mpc_oem,8); str[8]=0; printk(KERN_INFO "OEM ID: %s ",str); memcpy(str,mpc->mpc_productid,12); str[12]=0; printk("Product ID: %s ",str); printk("APIC at: 0x%X\n",mpc->mpc_lapic); /* save the local APIC address, it might be non-default */ if (!acpi_lapic) mp_lapic_addr = mpc->mpc_lapic; /* * Now process the configuration blocks. */ while (count < mpc->mpc_length) { switch(*mpt) { case MP_PROCESSOR: { struct mpc_config_processor *m= (struct mpc_config_processor *)mpt; if (!acpi_lapic) MP_processor_info(m); mpt += sizeof(*m); count += sizeof(*m); break; } case MP_BUS: { struct mpc_config_bus *m= (struct mpc_config_bus *)mpt; MP_bus_info(m); mpt += sizeof(*m); count += sizeof(*m); break; } case MP_IOAPIC: { struct mpc_config_ioapic *m= (struct mpc_config_ioapic *)mpt; MP_ioapic_info(m); mpt+=sizeof(*m); count+=sizeof(*m); break; } case MP_INTSRC: { struct mpc_config_intsrc *m= (struct mpc_config_intsrc *)mpt; MP_intsrc_info(m); mpt+=sizeof(*m); count+=sizeof(*m); break; } case MP_LINTSRC: { struct mpc_config_lintsrc *m= (struct mpc_config_lintsrc *)mpt; MP_lintsrc_info(m); mpt+=sizeof(*m); count+=sizeof(*m); break; } } } clustered_apic_check(); if (!num_processors) printk(KERN_ERR "SMP mptable: no processors registered!\n"); return num_processors; } static int __init ELCR_trigger(unsigned int irq) { unsigned int port; port = 0x4d0 + (irq >> 3); return (inb(port) >> (irq & 7)) & 1; } static void __init construct_default_ioirq_mptable(int mpc_default_type) { struct mpc_config_intsrc intsrc; int i; int ELCR_fallback = 0; intsrc.mpc_type = MP_INTSRC; intsrc.mpc_irqflag = 0; /* conforming */ intsrc.mpc_srcbus = 0; intsrc.mpc_dstapic = mp_ioapics[0].mpc_apicid; intsrc.mpc_irqtype = mp_INT; /* * If true, we have an ISA/PCI system with no IRQ entries * in the MP table. To prevent the PCI interrupts from being set up * incorrectly, we try to use the ELCR. The sanity check to see if * there is good ELCR data is very simple - IRQ0, 1, 2 and 13 can * never be level sensitive, so we simply see if the ELCR agrees. * If it does, we assume it's valid. */ if (mpc_default_type == 5) { printk(KERN_INFO "ISA/PCI bus type with no IRQ information... falling back to ELCR\n"); if (ELCR_trigger(0) || ELCR_trigger(1) || ELCR_trigger(2) || ELCR_trigger(13)) printk(KERN_ERR "ELCR contains invalid data... not using ELCR\n"); else { printk(KERN_INFO "Using ELCR to identify PCI interrupts\n"); ELCR_fallback = 1; } } for (i = 0; i < 16; i++) { switch (mpc_default_type) { case 2: if (i == 0 || i == 13) continue; /* IRQ0 & IRQ13 not connected */ /* fall through */ default: if (i == 2) continue; /* IRQ2 is never connected */ } if (ELCR_fallback) { /* * If the ELCR indicates a level-sensitive interrupt, we * copy that information over to the MP table in the * irqflag field (level sensitive, active high polarity). */ if (ELCR_trigger(i)) intsrc.mpc_irqflag = 13; else intsrc.mpc_irqflag = 0; } intsrc.mpc_srcbusirq = i; intsrc.mpc_dstirq = i ? i : 2; /* IRQ0 to INTIN2 */ MP_intsrc_info(&intsrc); } intsrc.mpc_irqtype = mp_ExtINT; intsrc.mpc_srcbusirq = 0; intsrc.mpc_dstirq = 0; /* 8259A to INTIN0 */ MP_intsrc_info(&intsrc); } static inline void __init construct_default_ISA_mptable(int mpc_default_type) { struct mpc_config_processor processor; struct mpc_config_bus bus; struct mpc_config_ioapic ioapic; struct mpc_config_lintsrc lintsrc; int linttypes[2] = { mp_ExtINT, mp_NMI }; int i; /* * local APIC has default address */ mp_lapic_addr = APIC_DEFAULT_PHYS_BASE; /* * 2 CPUs, numbered 0 & 1. */ processor.mpc_type = MP_PROCESSOR; processor.mpc_apicver = 0; processor.mpc_cpuflag = CPU_ENABLED; processor.mpc_cpufeature = 0; processor.mpc_featureflag = 0; processor.mpc_reserved[0] = 0; processor.mpc_reserved[1] = 0; for (i = 0; i < 2; i++) { processor.mpc_apicid = i; MP_processor_info(&processor); } bus.mpc_type = MP_BUS; bus.mpc_busid = 0; switch (mpc_default_type) { default: printk(KERN_ERR "???\nUnknown standard configuration %d\n", mpc_default_type); /* fall through */ case 1: case 5: memcpy(bus.mpc_bustype, "ISA ", 6); break; } MP_bus_info(&bus); if (mpc_default_type > 4) { bus.mpc_busid = 1; memcpy(bus.mpc_bustype, "PCI ", 6); MP_bus_info(&bus); } ioapic.mpc_type = MP_IOAPIC; ioapic.mpc_apicid = 2; ioapic.mpc_apicver = 0; ioapic.mpc_flags = MPC_APIC_USABLE; ioapic.mpc_apicaddr = 0xFEC00000; MP_ioapic_info(&ioapic); /* * We set up most of the low 16 IO-APIC pins according to MPS rules. */ construct_default_ioirq_mptable(mpc_default_type); lintsrc.mpc_type = MP_LINTSRC; lintsrc.mpc_irqflag = 0; /* conforming */ lintsrc.mpc_srcbusid = 0; lintsrc.mpc_srcbusirq = 0; lintsrc.mpc_destapic = MP_APIC_ALL; for (i = 0; i < 2; i++) { lintsrc.mpc_irqtype = linttypes[i]; lintsrc.mpc_destapiclint = i; MP_lintsrc_info(&lintsrc); } } static struct intel_mp_floating *mpf_found; /* * Scan the memory blocks for an SMP configuration block. */ void __init get_smp_config (void) { struct intel_mp_floating *mpf = mpf_found; /* * ACPI supports both logical (e.g. Hyper-Threading) and physical * processors, where MPS only supports physical. */ if (acpi_lapic && acpi_ioapic) { printk(KERN_INFO "Using ACPI (MADT) for SMP configuration information\n"); return; } else if (acpi_lapic) printk(KERN_INFO "Using ACPI for processor (LAPIC) configuration information\n"); printk("Intel MultiProcessor Specification v1.%d\n", mpf->mpf_specification); /* * Now see if we need to read further. */ if (mpf->mpf_feature1 != 0) { printk(KERN_INFO "Default MP configuration #%d\n", mpf->mpf_feature1); construct_default_ISA_mptable(mpf->mpf_feature1); } else if (mpf->mpf_physptr) { /* * Read the physical hardware table. Anything here will * override the defaults. */ if (!smp_read_mpc(phys_to_virt(mpf->mpf_physptr))) { smp_found_config = 0; printk(KERN_ERR "BIOS bug, MP table errors detected!...\n"); printk(KERN_ERR "... disabling SMP support. (tell your hw vendor)\n"); return; } /* * If there are no explicit MP IRQ entries, then we are * broken. We set up most of the low 16 IO-APIC pins to * ISA defaults and hope it will work. */ if (!mp_irq_entries) { struct mpc_config_bus bus; printk(KERN_ERR "BIOS bug, no explicit IRQ entries, using default mptable. (tell your hw vendor)\n"); bus.mpc_type = MP_BUS; bus.mpc_busid = 0; memcpy(bus.mpc_bustype, "ISA ", 6); MP_bus_info(&bus); construct_default_ioirq_mptable(0); } } else BUG(); printk(KERN_INFO "Processors: %d\n", num_processors); /* * Only use the first configuration found. */ } static int __init smp_scan_config (unsigned long base, unsigned long length) { extern void __bad_mpf_size(void); unsigned int *bp = phys_to_virt(base); struct intel_mp_floating *mpf; Dprintk("Scan SMP from %p for %ld bytes.\n", bp,length); if (sizeof(*mpf) != 16) __bad_mpf_size(); while (length > 0) { mpf = (struct intel_mp_floating *)bp; if ((*bp == SMP_MAGIC_IDENT) && (mpf->mpf_length == 1) && !mpf_checksum((unsigned char *)bp, 16) && ((mpf->mpf_specification == 1) || (mpf->mpf_specification == 4)) ) { smp_found_config = 1; reserve_bootmem_generic(virt_to_phys(mpf), PAGE_SIZE); if (mpf->mpf_physptr) reserve_bootmem_generic(mpf->mpf_physptr, PAGE_SIZE); mpf_found = mpf; return 1; } bp += 4; length -= 16; } return 0; } void __init find_smp_config(void) { unsigned int address; /* * FIXME: Linux assumes you have 640K of base ram.. * this continues the error... * * 1) Scan the bottom 1K for a signature * 2) Scan the top 1K of base RAM * 3) Scan the 64K of bios */ if (smp_scan_config(0x0,0x400) || smp_scan_config(639*0x400,0x400) || smp_scan_config(0xF0000,0x10000)) return; /* * If it is an SMP machine we should know now. * * there is a real-mode segmented pointer pointing to the * 4K EBDA area at 0x40E, calculate and scan it here. * * NOTE! There are Linux loaders that will corrupt the EBDA * area, and as such this kind of SMP config may be less * trustworthy, simply because the SMP table may have been * stomped on during early boot. These loaders are buggy and * should be fixed. */ address = *(unsigned short *)phys_to_virt(0x40E); address <<= 4; if (smp_scan_config(address, 0x1000)) return; /* If we have come this far, we did not find an MP table */ printk(KERN_INFO "No mptable found.\n"); } /* -------------------------------------------------------------------------- ACPI-based MP Configuration -------------------------------------------------------------------------- */ #ifdef CONFIG_ACPI void __init mp_register_lapic_address(u64 address) { mp_lapic_addr = (unsigned long) address; set_fixmap_nocache(FIX_APIC_BASE, mp_lapic_addr); if (boot_cpu_id == -1U) boot_cpu_id = GET_APIC_ID(apic_read(APIC_ID)); Dprintk("Boot CPU = %d\n", boot_cpu_physical_apicid); } void __cpuinit mp_register_lapic (u8 id, u8 enabled) { struct mpc_config_processor processor; int boot_cpu = 0; if (id >= MAX_APICS) { printk(KERN_WARNING "Processor #%d invalid (max %d)\n", id, MAX_APICS); return; } if (id == boot_cpu_physical_apicid) boot_cpu = 1; processor.mpc_type = MP_PROCESSOR; processor.mpc_apicid = id; processor.mpc_apicver = 0; processor.mpc_cpuflag = (enabled ? CPU_ENABLED : 0); processor.mpc_cpuflag |= (boot_cpu ? CPU_BOOTPROCESSOR : 0); processor.mpc_cpufeature = 0; processor.mpc_featureflag = 0; processor.mpc_reserved[0] = 0; processor.mpc_reserved[1] = 0; MP_processor_info(&processor); } #define MP_ISA_BUS 0 #define MP_MAX_IOAPIC_PIN 127 static struct mp_ioapic_routing { int apic_id; int gsi_start; int gsi_end; u32 pin_programmed[4]; } mp_ioapic_routing[MAX_IO_APICS]; static int mp_find_ioapic(int gsi) { int i = 0; /* Find the IOAPIC that manages this GSI. */ for (i = 0; i < nr_ioapics; i++) { if ((gsi >= mp_ioapic_routing[i].gsi_start) && (gsi <= mp_ioapic_routing[i].gsi_end)) return i; } printk(KERN_ERR "ERROR: Unable to locate IOAPIC for GSI %d\n", gsi); return -1; } void __init mp_register_ioapic(u8 id, u32 address, u32 gsi_base) { int idx = 0; if (nr_ioapics >= MAX_IO_APICS) { printk(KERN_ERR "ERROR: Max # of I/O APICs (%d) exceeded " "(found %d)\n", MAX_IO_APICS, nr_ioapics); panic("Recompile kernel with bigger MAX_IO_APICS!\n"); } if (!address) { printk(KERN_ERR "WARNING: Bogus (zero) I/O APIC address" " found in MADT table, skipping!\n"); return; } idx = nr_ioapics++; mp_ioapics[idx].mpc_type = MP_IOAPIC; mp_ioapics[idx].mpc_flags = MPC_APIC_USABLE; mp_ioapics[idx].mpc_apicaddr = address; set_fixmap_nocache(FIX_IO_APIC_BASE_0 + idx, address); mp_ioapics[idx].mpc_apicid = id; mp_ioapics[idx].mpc_apicver = 0; /* * Build basic IRQ lookup table to facilitate gsi->io_apic lookups * and to prevent reprogramming of IOAPIC pins (PCI IRQs). */ mp_ioapic_routing[idx].apic_id = mp_ioapics[idx].mpc_apicid; mp_ioapic_routing[idx].gsi_start = gsi_base; mp_ioapic_routing[idx].gsi_end = gsi_base + io_apic_get_redir_entries(idx); printk(KERN_INFO "IOAPIC[%d]: apic_id %d, address 0x%x, " "GSI %d-%d\n", idx, mp_ioapics[idx].mpc_apicid, mp_ioapics[idx].mpc_apicaddr, mp_ioapic_routing[idx].gsi_start, mp_ioapic_routing[idx].gsi_end); } void __init mp_override_legacy_irq(u8 bus_irq, u8 polarity, u8 trigger, u32 gsi) { struct mpc_config_intsrc intsrc; int ioapic = -1; int pin = -1; /* * Convert 'gsi' to 'ioapic.pin'. */ ioapic = mp_find_ioapic(gsi); if (ioapic < 0) return; pin = gsi - mp_ioapic_routing[ioapic].gsi_start; /* * TBD: This check is for faulty timer entries, where the override * erroneously sets the trigger to level, resulting in a HUGE * increase of timer interrupts! */ if ((bus_irq == 0) && (trigger == 3)) trigger = 1; intsrc.mpc_type = MP_INTSRC; intsrc.mpc_irqtype = mp_INT; intsrc.mpc_irqflag = (trigger << 2) | polarity; intsrc.mpc_srcbus = MP_ISA_BUS; intsrc.mpc_srcbusirq = bus_irq; /* IRQ */ intsrc.mpc_dstapic = mp_ioapics[ioapic].mpc_apicid; /* APIC ID */ intsrc.mpc_dstirq = pin; /* INTIN# */ Dprintk("Int: type %d, pol %d, trig %d, bus %d, irq %d, %d-%d\n", intsrc.mpc_irqtype, intsrc.mpc_irqflag & 3, (intsrc.mpc_irqflag >> 2) & 3, intsrc.mpc_srcbus, intsrc.mpc_srcbusirq, intsrc.mpc_dstapic, intsrc.mpc_dstirq); mp_irqs[mp_irq_entries] = intsrc; if (++mp_irq_entries == MAX_IRQ_SOURCES) panic("Max # of irq sources exceeded!\n"); } void __init mp_config_acpi_legacy_irqs(void) { struct mpc_config_intsrc intsrc; int i = 0; int ioapic = -1; /* * Fabricate the legacy ISA bus (bus #31). */ set_bit(MP_ISA_BUS, mp_bus_not_pci); /* * Locate the IOAPIC that manages the ISA IRQs (0-15). */ ioapic = mp_find_ioapic(0); if (ioapic < 0) return; intsrc.mpc_type = MP_INTSRC; intsrc.mpc_irqflag = 0; /* Conforming */ intsrc.mpc_srcbus = MP_ISA_BUS; intsrc.mpc_dstapic = mp_ioapics[ioapic].mpc_apicid; /* * Use the default configuration for the IRQs 0-15. Unless * overridden by (MADT) interrupt source override entries. */ for (i = 0; i < 16; i++) { int idx; for (idx = 0; idx < mp_irq_entries; idx++) { struct mpc_config_intsrc *irq = mp_irqs + idx; /* Do we already have a mapping for this ISA IRQ? */ if (irq->mpc_srcbus == MP_ISA_BUS && irq->mpc_srcbusirq == i) break; /* Do we already have a mapping for this IOAPIC pin */ if ((irq->mpc_dstapic == intsrc.mpc_dstapic) && (irq->mpc_dstirq == i)) break; } if (idx != mp_irq_entries) { printk(KERN_DEBUG "ACPI: IRQ%d used by override.\n", i); continue; /* IRQ already used */ } intsrc.mpc_irqtype = mp_INT; intsrc.mpc_srcbusirq = i; /* Identity mapped */ intsrc.mpc_dstirq = i; Dprintk("Int: type %d, pol %d, trig %d, bus %d, irq %d, " "%d-%d\n", intsrc.mpc_irqtype, intsrc.mpc_irqflag & 3, (intsrc.mpc_irqflag >> 2) & 3, intsrc.mpc_srcbus, intsrc.mpc_srcbusirq, intsrc.mpc_dstapic, intsrc.mpc_dstirq); mp_irqs[mp_irq_entries] = intsrc; if (++mp_irq_entries == MAX_IRQ_SOURCES) panic("Max # of irq sources exceeded!\n"); } } #define MAX_GSI_NUM 4096 int mp_register_gsi(u32 gsi, int triggering, int polarity) { int ioapic = -1; int ioapic_pin = 0; int idx, bit = 0; static int pci_irq = 16; /* * Mapping between Global System Interrupts, which * represent all possible interrupts, to the IRQs * assigned to actual devices. */ static int gsi_to_irq[MAX_GSI_NUM]; if (acpi_irq_model != ACPI_IRQ_MODEL_IOAPIC) return gsi; /* Don't set up the ACPI SCI because it's already set up */ if (acpi_fadt.sci_int == gsi) return gsi; ioapic = mp_find_ioapic(gsi); if (ioapic < 0) { printk(KERN_WARNING "No IOAPIC for GSI %u\n", gsi); return gsi; } ioapic_pin = gsi - mp_ioapic_routing[ioapic].gsi_start; /* * Avoid pin reprogramming. PRTs typically include entries * with redundant pin->gsi mappings (but unique PCI devices); * we only program the IOAPIC on the first. */ bit = ioapic_pin % 32; idx = (ioapic_pin < 32) ? 0 : (ioapic_pin / 32); if (idx > 3) { printk(KERN_ERR "Invalid reference to IOAPIC pin " "%d-%d\n", mp_ioapic_routing[ioapic].apic_id, ioapic_pin); return gsi; } if ((1< 15), but * avoid a problem where the 8254 timer (IRQ0) is setup * via an override (so it's not on pin 0 of the ioapic), * and at the same time, the pin 0 interrupt is a PCI * type. The gsi > 15 test could cause these two pins * to be shared as IRQ0, and they are not shareable. * So test for this condition, and if necessary, avoid * the pin collision. */ if (gsi > 15 || (gsi == 0 && !timer_uses_ioapic_pin_0)) gsi = pci_irq++; /* * Don't assign IRQ used by ACPI SCI */ if (gsi == acpi_fadt.sci_int) gsi = pci_irq++; gsi_to_irq[irq] = gsi; } else { printk(KERN_ERR "GSI %u is too high\n", gsi); return gsi; } } io_apic_set_pci_routing(ioapic, ioapic_pin, gsi, triggering == ACPI_EDGE_SENSITIVE ? 0 : 1, polarity == ACPI_ACTIVE_HIGH ? 0 : 1); return gsi; } #endif /*CONFIG_ACPI*/