source: trunk/packages/xen-3.1/xen-3.1/xen/arch/x86/mpparse.c @ 34

/*
 *      Intel Multiprocessor Specification 1.1 and 1.4
 *      compliant MP-table parsing routines.
 *
 *      (c) 1995 Alan Cox, Building #3 <alan@redhat.com>
 *      (c) 1998, 1999, 2000 Ingo Molnar <mingo@redhat.com>
 *
 *      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 <xen/config.h>
#include <xen/types.h>
#include <xen/irq.h>
#include <xen/init.h>
#include <xen/acpi.h>
#include <xen/delay.h>
#include <xen/sched.h>

#include <asm/mc146818rtc.h>
#include <asm/bitops.h>
#include <asm/smp.h>
#include <asm/acpi.h>
#include <asm/mtrr.h>
#include <asm/mpspec.h>
#include <asm/io_apic.h>

#include <mach_apic.h>
#include <mach_mpparse.h>
#include <bios_ebda.h>

/* Have we found an MP table */
int smp_found_config;
unsigned int __initdata maxcpus = NR_CPUS;

/*
 * Various Linux-internal data structures created from the
 * MP-table.
 */
int apic_version [MAX_APICS];
int mp_bus_id_to_type [MAX_MP_BUSSES];
int mp_bus_id_to_node [MAX_MP_BUSSES];
int mp_bus_id_to_local [MAX_MP_BUSSES];
int quad_local_to_mp_bus_id [NR_CPUS/4][4];
int mp_bus_id_to_pci_bus [MAX_MP_BUSSES] = { [0 ... MAX_MP_BUSSES-1] = -1 };
static int mp_current_pci_id;

/* 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;

int pic_mode;
unsigned long mp_lapic_addr;

unsigned int def_to_bigsmp = 0;

/* Processor that is doing the boot up */
unsigned int boot_cpu_physical_apicid = -1U;
/* Internal processor count */
static unsigned int __devinitdata num_processors;

/* Bitmask of physically existing CPUs */
physid_mask_t phys_cpu_present_map;

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;
}

/*
 * Have to match translation table entries to main table entries by counter
 * hence the mpc_record variable .... can't see a less disgusting way of
 * doing this ....
 */

static int mpc_record; 
static struct mpc_config_translation *translation_table[MAX_MPC_ENTRY] __initdata;

static void __devinit MP_processor_info (struct mpc_config_processor *m)
{
        int ver, apicid;
        physid_mask_t phys_cpu;
        
        if (!(m->mpc_cpuflag & CPU_ENABLED))
                return;

        apicid = mpc_apic_id(m, translation_table[mpc_record]);

        if (m->mpc_featureflag&(1<<0))
                Dprintk("    Floating point unit present.\n");
        if (m->mpc_featureflag&(1<<7))
                Dprintk("    Machine Exception supported.\n");
        if (m->mpc_featureflag&(1<<8))
                Dprintk("    64 bit compare & exchange supported.\n");
        if (m->mpc_featureflag&(1<<9))
                Dprintk("    Internal APIC present.\n");
        if (m->mpc_featureflag&(1<<11))
                Dprintk("    SEP present.\n");
        if (m->mpc_featureflag&(1<<12))
                Dprintk("    MTRR  present.\n");
        if (m->mpc_featureflag&(1<<13))
                Dprintk("    PGE  present.\n");
        if (m->mpc_featureflag&(1<<14))
                Dprintk("    MCA  present.\n");
        if (m->mpc_featureflag&(1<<15))
                Dprintk("    CMOV  present.\n");
        if (m->mpc_featureflag&(1<<16))
                Dprintk("    PAT  present.\n");
        if (m->mpc_featureflag&(1<<17))
                Dprintk("    PSE  present.\n");
        if (m->mpc_featureflag&(1<<18))
                Dprintk("    PSN  present.\n");
        if (m->mpc_featureflag&(1<<19))
                Dprintk("    Cache Line Flush Instruction present.\n");
        /* 20 Reserved */
        if (m->mpc_featureflag&(1<<21))
                Dprintk("    Debug Trace and EMON Store present.\n");
        if (m->mpc_featureflag&(1<<22))
                Dprintk("    ACPI Thermal Throttle Registers  present.\n");
        if (m->mpc_featureflag&(1<<23))
                Dprintk("    MMX  present.\n");
        if (m->mpc_featureflag&(1<<24))
                Dprintk("    FXSR  present.\n");
        if (m->mpc_featureflag&(1<<25))
                Dprintk("    XMM  present.\n");
        if (m->mpc_featureflag&(1<<26))
                Dprintk("    Willamette New Instructions  present.\n");
        if (m->mpc_featureflag&(1<<27))
                Dprintk("    Self Snoop  present.\n");
        if (m->mpc_featureflag&(1<<28))
                Dprintk("    HT  present.\n");
        if (m->mpc_featureflag&(1<<29))
                Dprintk("    Thermal Monitor present.\n");
        /* 30, 31 Reserved */


        if (m->mpc_cpuflag & CPU_BOOTPROCESSOR) {
                Dprintk("    Bootup CPU\n");
                boot_cpu_physical_apicid = m->mpc_apicid;
        }

        ver = m->mpc_apicver;

        /*
         * Validate version
         */
        if (ver == 0x0) {
                printk(KERN_WARNING "BIOS bug, APIC version is 0 for CPU#%d! "
                                "fixing up to 0x10. (tell your hw vendor)\n",
                                m->mpc_apicid);
                ver = 0x10;
        }
        apic_version[m->mpc_apicid] = ver;

        phys_cpu = apicid_to_cpu_present(apicid);
        physids_or(phys_cpu_present_map, phys_cpu_present_map, phys_cpu);

        if (num_processors >= NR_CPUS) {
                printk(KERN_WARNING "WARNING: NR_CPUS limit of %i reached."
                        "  Processor ignored.\n", NR_CPUS);
                return;
        }

        if (num_processors >= maxcpus) {
                printk(KERN_WARNING "WARNING: maxcpus limit of %i reached."
                        " Processor ignored.\n", maxcpus);
                return;
        }

        cpu_set(num_processors, cpu_possible_map);
        num_processors++;

        if (num_processors > 8) {
                /*
                 * No need for processor or APIC checks: physical delivery
                 * (bigsmp) mode should always work.
                 */
                def_to_bigsmp = 1;
        }
        bios_cpu_apicid[num_processors - 1] = m->mpc_apicid;
}

static void __init MP_bus_info (struct mpc_config_bus *m)
{
        char str[7];

        memcpy(str, m->mpc_bustype, 6);
        str[6] = 0;

        mpc_oem_bus_info(m, str, translation_table[mpc_record]);

#if 0 /* size of mpc_busid (8 bits) makes this check unnecessary */
        if (m->mpc_busid >= MAX_MP_BUSSES) {
                printk(KERN_WARNING "MP table busid value (%d) for bustype %s "
                        " is too large, max. supported is %d\n",
                        m->mpc_busid, str, MAX_MP_BUSSES - 1);
                return;
        }
#endif

        if (strncmp(str, BUSTYPE_ISA, sizeof(BUSTYPE_ISA)-1) == 0) {
                mp_bus_id_to_type[m->mpc_busid] = MP_BUS_ISA;
        } else if (strncmp(str, BUSTYPE_EISA, sizeof(BUSTYPE_EISA)-1) == 0) {
                mp_bus_id_to_type[m->mpc_busid] = MP_BUS_EISA;
        } else if (strncmp(str, BUSTYPE_PCI, sizeof(BUSTYPE_PCI)-1) == 0) {
                mpc_oem_pci_bus(m, translation_table[mpc_record]);
                mp_bus_id_to_type[m->mpc_busid] = MP_BUS_PCI;
                mp_bus_id_to_pci_bus[m->mpc_busid] = mp_current_pci_id;
                mp_current_pci_id++;
        } else if (strncmp(str, BUSTYPE_MCA, sizeof(BUSTYPE_MCA)-1) == 0) {
                mp_bus_id_to_type[m->mpc_busid] = MP_BUS_MCA;
        } else if (strncmp(str, BUSTYPE_NEC98, sizeof(BUSTYPE_NEC98)-1) == 0) {
                mp_bus_id_to_type[m->mpc_busid] = MP_BUS_NEC98;
        } else {
                printk(KERN_WARNING "Unknown bustype %s - ignoring\n", str);
        }
}

static void __init MP_ioapic_info (struct mpc_config_ioapic *m)
{
        if (!(m->mpc_flags & MPC_APIC_USABLE))
                return;

        printk(KERN_INFO "I/O APIC #%d Version %d at 0x%X.\n",
                m->mpc_apicid, m->mpc_apicver, m->mpc_apicaddr);
        if (nr_ioapics >= MAX_IO_APICS) {
                printk(KERN_CRIT "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);
        /*
         * Well it seems all SMP boards in existence
         * use ExtINT/LVT1 == LINT0 and
         * NMI/LVT2 == LINT1 - the following check
         * will show us if this assumptions is false.
         * Until then we do not have to add baggage.
         */
        if ((m->mpc_irqtype == mp_ExtINT) &&
                (m->mpc_destapiclint != 0))
                        BUG();
        if ((m->mpc_irqtype == mp_NMI) &&
                (m->mpc_destapiclint != 1))
                        BUG();
}

#ifdef CONFIG_X86_NUMAQ
static void __init MP_translation_info (struct mpc_config_translation *m)
{
        printk(KERN_INFO "Translation: record %d, type %d, quad %d, global %d, local %d\n", mpc_record, m->trans_type, m->trans_quad, m->trans_global, m->trans_local);

        if (mpc_record >= MAX_MPC_ENTRY) 
                printk(KERN_ERR "MAX_MPC_ENTRY exceeded!\n");
        else
                translation_table[mpc_record] = m; /* stash this for later */
        if (m->trans_quad < MAX_NUMNODES && !node_online(m->trans_quad))
                node_set_online(m->trans_quad);
}

/*
 * Read/parse the MPC oem tables
 */

static void __init smp_read_mpc_oem(struct mp_config_oemtable *oemtable, \
        unsigned short oemsize)
{
        int count = sizeof (*oemtable); /* the header size */
        unsigned char *oemptr = ((unsigned char *)oemtable)+count;
        
        mpc_record = 0;
        printk(KERN_INFO "Found an OEM MPC table at %8p - parsing it ... \n", oemtable);
        if (memcmp(oemtable->oem_signature,MPC_OEM_SIGNATURE,4))
        {
                printk(KERN_WARNING "SMP mpc oemtable: bad signature [%c%c%c%c]!\n",
                        oemtable->oem_signature[0],
                        oemtable->oem_signature[1],
                        oemtable->oem_signature[2],
                        oemtable->oem_signature[3]);
                return;
        }
        if (mpf_checksum((unsigned char *)oemtable,oemtable->oem_length))
        {
                printk(KERN_WARNING "SMP oem mptable: checksum error!\n");
                return;
        }
        while (count < oemtable->oem_length) {
                switch (*oemptr) {
                        case MP_TRANSLATION:
                        {
                                struct mpc_config_translation *m=
                                        (struct mpc_config_translation *)oemptr;
                                MP_translation_info(m);
                                oemptr += sizeof(*m);
                                count += sizeof(*m);
                                ++mpc_record;
                                break;
                        }
                        default:
                        {
                                printk(KERN_WARNING "Unrecognised OEM table entry type! - %d\n", (int) *oemptr);
                                return;
                        }
                }
       }
}

static inline void mps_oem_check(struct mp_config_table *mpc, char *oem,
                char *productid)
{
        if (strncmp(oem, "IBM NUMA", 8))
                printk("Warning!  May not be a NUMA-Q system!\n");
        if (mpc->mpc_oemptr)
                smp_read_mpc_oem((struct mp_config_oemtable *) mpc->mpc_oemptr,
                                mpc->mpc_oemsize);
}
#endif  /* CONFIG_X86_NUMAQ */

/*
 * Read/parse the MPC
 */

static int __init smp_read_mpc(struct mp_config_table *mpc)
{
        char str[16];
        char oem[10];
        int count=sizeof(*mpc);
        unsigned char *mpt=((unsigned char *)mpc)+count;

        if (memcmp(mpc->mpc_signature,MPC_SIGNATURE,4)) {
                printk(KERN_ERR "SMP mptable: bad signature [0x%x]!\n",
                        *(u32 *)mpc->mpc_signature);
                return 0;
        }
        if (mpf_checksum((unsigned char *)mpc,mpc->mpc_length)) {
                printk(KERN_ERR "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(oem,mpc->mpc_oem,8);
        oem[8]=0;
        printk(KERN_INFO "OEM ID: %s ",oem);

        memcpy(str,mpc->mpc_productid,12);
        str[12]=0;
        printk("Product ID: %s ",str);

        mps_oem_check(mpc, oem, str);

        printk("APIC at: 0x%X\n",mpc->mpc_lapic);

        /* 
         * Save the local APIC address (it might be non-default) -- but only
         * if we're not using ACPI.
         */
        if (!acpi_lapic)
                mp_lapic_addr = mpc->mpc_lapic;

        /*
         *      Now process the configuration blocks.
         */
        mpc_record = 0;
        while (count < mpc->mpc_length) {
                switch(*mpt) {
                        case MP_PROCESSOR:
                        {
                                struct mpc_config_processor *m=
                                        (struct mpc_config_processor *)mpt;
                                /* ACPI may have already provided this data */
                                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;
                        }
                        default:
                        {
                                count = mpc->mpc_length;
                                break;
                        }
                }
                ++mpc_record;
        }
        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_WARNING "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;
        /* Either an integrated APIC or a discrete 82489DX. */
        processor.mpc_apicver = mpc_default_type > 4 ? 0x10 : 0x01;
        processor.mpc_cpuflag = CPU_ENABLED;
        processor.mpc_cpufeature = (boot_cpu_data.x86 << 8) |
                                   (boot_cpu_data.x86_model << 4) |
                                   boot_cpu_data.x86_mask;
        processor.mpc_featureflag = boot_cpu_data.x86_capability[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("???\n");
                        printk(KERN_ERR "Unknown standard configuration %d\n",
                                mpc_default_type);
                        /* fall through */
                case 1:
                case 5:
                        memcpy(bus.mpc_bustype, "ISA   ", 6);
                        break;
                case 2:
                case 6:
                case 3:
                        memcpy(bus.mpc_bustype, "EISA  ", 6);
                        break;
                case 4:
                case 7:
                        memcpy(bus.mpc_bustype, "MCA   ", 6);
        }
        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 = mpc_default_type > 4 ? 0x10 : 0x01;
        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(KERN_INFO "Intel MultiProcessor Specification v1.%d\n", mpf->mpf_specification);
        if (mpf->mpf_feature2 & (1<<7)) {
                printk(KERN_INFO "    IMCR and PIC compatibility mode.\n");
                pic_mode = 1;
        } else {
                printk(KERN_INFO "    Virtual Wire compatibility mode.\n");
                pic_mode = 0;
        }

        /*
         * 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((void *)(unsigned long)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)
{
        unsigned int *bp = maddr_to_virt(base);
        struct intel_mp_floating *mpf;

        Dprintk("Scan SMP from %p for %ld bytes.\n", bp,length);
        if (sizeof(*mpf) != 16)
                printk("Error: MPF size\n");

        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;
                        printk(KERN_INFO "found SMP MP-table at %08lx\n",
                                                virt_to_maddr(mpf));
#if 0
                        reserve_bootmem(virt_to_maddr(mpf), PAGE_SIZE);
                        if (mpf->mpf_physptr) {
                                /*
                                 * We cannot access to MPC table to compute
                                 * table size yet, as only few megabytes from
                                 * the bottom is mapped now.
                                 * PC-9800's MPC table places on the very last
                                 * of physical memory; so that simply reserving
                                 * PAGE_SIZE from mpg->mpf_physptr yields BUG()
                                 * in reserve_bootmem.
                                 */
                                unsigned long size = PAGE_SIZE;
                                unsigned long end = max_low_pfn * PAGE_SIZE;
                                if (mpf->mpf_physptr + size > end)
                                        size = end - mpf->mpf_physptr;
                                reserve_bootmem(mpf->mpf_physptr, size);
                        }
#endif
                        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, unless the
         * configuration is in an EISA/MCA bus machine with an
         * extended bios data area.
         *
         * 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.
         *
         * MP1.4 SPEC states to only scan first 1K of 4K EBDA.
         */

        address = get_bios_ebda();
        if (address)
                smp_scan_config(address, 0x400);
}

/* --------------------------------------------------------------------------
                            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_physical_apicid == -1U)
                boot_cpu_physical_apicid = GET_APIC_ID(apic_read(APIC_ID));

        Dprintk("Boot CPU = %d\n", boot_cpu_physical_apicid);
}


void __devinit mp_register_lapic (
        u8                      id, 
        u8                      enabled)
{
        struct mpc_config_processor processor;
        int                     boot_cpu = 0;
        
        if (MAX_APICS - id <= 0) {
                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 = GET_APIC_VERSION(apic_read(APIC_LVR));
        processor.mpc_cpuflag = (enabled ? CPU_ENABLED : 0);
        processor.mpc_cpuflag |= (boot_cpu ? CPU_BOOTPROCESSOR : 0);
        processor.mpc_cpufeature = (boot_cpu_data.x86 << 8) | 
                (boot_cpu_data.x86_model << 4) | boot_cpu_data.x86_mask;
        processor.mpc_featureflag = boot_cpu_data.x86_capability[0];
        processor.mpc_reserved[0] = 0;
        processor.mpc_reserved[1] = 0;

        MP_processor_info(&processor);
}

#ifdef  CONFIG_X86_IO_APIC

#define MP_ISA_BUS              0
#define MP_MAX_IOAPIC_PIN       127

static struct mp_ioapic_routing {
        int                     apic_id;
        int                     gsi_base;
        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_base)
                        && (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;
        int                     tmpid;

        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);
        if ((boot_cpu_data.x86_vendor == X86_VENDOR_INTEL)
                && !APIC_XAPIC(apic_version[boot_cpu_physical_apicid]))
                tmpid = io_apic_get_unique_id(idx, id);
        else
                tmpid = id;
        if (tmpid == -1) {
                nr_ioapics--;
                return;
        }
        mp_ioapics[idx].mpc_apicid = tmpid;
        mp_ioapics[idx].mpc_apicver = io_apic_get_version(idx);
        
        /* 
         * Build basic GSI lookup table to facilitate gsi->io_apic lookups
         * and to prevent reprogramming of IOAPIC pins (PCI GSIs).
         */
        mp_ioapic_routing[idx].apic_id = mp_ioapics[idx].mpc_apicid;
        mp_ioapic_routing[idx].gsi_base = gsi_base;
        mp_ioapic_routing[idx].gsi_end = gsi_base + 
                io_apic_get_redir_entries(idx);

        printk("IOAPIC[%d]: apic_id %d, version %d, address 0x%x, "
                "GSI %d-%d\n", idx, mp_ioapics[idx].mpc_apicid, 
                mp_ioapics[idx].mpc_apicver, mp_ioapics[idx].mpc_apicaddr,
                mp_ioapic_routing[idx].gsi_base,
                mp_ioapic_routing[idx].gsi_end);

        return;
}


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_base;

        /*
         * 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");

        return;
}

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).
         */
        mp_bus_id_to_type[MP_ISA_BUS] = MP_BUS_ISA;
        Dprintk("Bus #%d is ISA\n", MP_ISA_BUS);

        /*
         * Older generations of ES7000 have no legacy identity mappings
         */
        if (es7000_plat == 1)
                return;

        /* 
         * 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
         * overriden 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 Interrups, which
         * represent all possible interrupts, and IRQs
         * assigned to actual devices.
         */
        static int              gsi_to_irq[MAX_GSI_NUM];

#ifdef CONFIG_ACPI_BUS
        /* Don't set up the ACPI SCI because it's already set up */
        if (acpi_fadt.sci_int == gsi)
                return gsi;
#endif

        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_base;

        if (ioapic_renumber_irq)
                gsi = ioapic_renumber_irq(ioapic, gsi);

        /* 
         * 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<<bit) & mp_ioapic_routing[ioapic].pin_programmed[idx]) {
                Dprintk(KERN_DEBUG "Pin %d-%d already programmed\n",
                        mp_ioapic_routing[ioapic].apic_id, ioapic_pin);
                return gsi_to_irq[gsi];
        }

        mp_ioapic_routing[ioapic].pin_programmed[idx] |= (1<<bit);

        if (triggering == ACPI_LEVEL_SENSITIVE) {
                /*
                 * For PCI devices assign IRQs in order, avoiding gaps
                 * due to unused I/O APIC pins.
                 */
                int irq = gsi;
                if (gsi < MAX_GSI_NUM) {
                        /*
                         * Retain the VIA chipset work-around (gsi > 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++;
#ifdef CONFIG_ACPI_BUS
                        /*
                         * Don't assign IRQ used by ACPI SCI
                         */
                        if (gsi == acpi_fadt.sci_int)
                                gsi = pci_irq++;
#endif
                        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_X86_IO_APIC */
#endif /* CONFIG_ACPI */