io_apic.c

xen虚拟机源代码安装包

        /*
         * legacy devices should be connected to IO APIC #0
         */
        setup_ExtINT_IRQ0_pin(apic2, pin2, vector);
        if (timer_irq_works()) {
            printk("works.\n");
            if (pin1 != -1)
                replace_pin_at_irq(0, apic1, pin1, apic2, pin2);
            else
                add_pin_to_irq(0, apic2, pin2);
            return;
        }
        /*
         * Cleanup, just in case ...
         */
        clear_IO_APIC_pin(apic2, pin2);
    }
    printk(" failed.\n");

    if (nmi_watchdog == NMI_IO_APIC) {
        printk(KERN_WARNING "timer doesn't work through the IO-APIC - disabling NMI Watchdog!\n");
        nmi_watchdog = 0;
    }

    printk(KERN_INFO "...trying to set up timer as Virtual Wire IRQ...");

    disable_8259A_irq(0);
    irq_desc[vector].handler = &lapic_irq_type;
    apic_write_around(APIC_LVT0, APIC_DM_FIXED | vector);	/* Fixed mode */
    enable_8259A_irq(0);

    if (timer_irq_works()) {
        printk(" works.\n");
        return;
    }
    apic_write_around(APIC_LVT0, APIC_LVT_MASKED | APIC_DM_FIXED | vector);
    printk(" failed.\n");

    printk(KERN_INFO "...trying to set up timer as ExtINT IRQ...");

    /*timer_ack = 0;*/
    init_8259A(0);
    make_8259A_irq(0);
    apic_write_around(APIC_LVT0, APIC_DM_EXTINT);

    unlock_ExtINT_logic();

    if (timer_irq_works()) {
        printk(" works.\n");
        return;
    }
    printk(" failed :(.\n");
    panic("IO-APIC + timer doesn't work!  Boot with apic=debug and send a "
          "report.  Then try booting with the 'noapic' option");
}

/*
 *
 * IRQ's that are handled by the PIC in the MPS IOAPIC case.
 * - IRQ2 is the cascade IRQ, and cannot be a io-apic IRQ.
 *   Linux doesn't really care, as it's not actually used
 *   for any interrupt handling anyway.
 */
#define PIC_IRQS	(1 << PIC_CASCADE_IR)

void __init setup_IO_APIC(void)
{
    enable_IO_APIC();

    if (acpi_ioapic)
        io_apic_irqs = ~0;	/* all IRQs go through IOAPIC */
    else
        io_apic_irqs = ~PIC_IRQS;

    printk("ENABLING IO-APIC IRQs\n");
    printk(" -> Using %s ACK method\n", ioapic_ack_new ? "new" : "old");

    /*
     * Set up IO-APIC IRQ routing.
     */
    if (!acpi_ioapic)
        setup_ioapic_ids_from_mpc();
    sync_Arb_IDs();
    setup_IO_APIC_irqs();
    init_IO_APIC_traps();
    check_timer();
    print_IO_APIC();

    register_keyhandler('z', print_IO_APIC_keyhandler, "print ioapic info");
}

struct IO_APIC_route_entry *ioapic_pm_state=NULL;

void ioapic_pm_state_alloc(void)
{
    int i, nr_entry = 0;

    if (ioapic_pm_state != NULL)
        return;

    for (i = 0; i < nr_ioapics; i++)
        nr_entry += nr_ioapic_registers[i];

    ioapic_pm_state = _xmalloc(sizeof(struct IO_APIC_route_entry)*nr_entry,
                               sizeof(struct IO_APIC_route_entry));
}

int ioapic_suspend(void)
{
    struct IO_APIC_route_entry *entry;
    unsigned long flags;
    int apic,i;

    ioapic_pm_state_alloc();

    if (ioapic_pm_state == NULL) {
        printk("Cannot suspend ioapic due to lack of memory\n");
        return 1;
    }

    entry = ioapic_pm_state;

    spin_lock_irqsave(&ioapic_lock, flags);
    for (apic = 0; apic < nr_ioapics; apic++) {
        for (i = 0; i < nr_ioapic_registers[apic]; i ++, entry ++ ) {
            *(((int *)entry) + 1) = io_apic_read(apic, 0x11 + 2 * i);
            *(((int *)entry) + 0) = io_apic_read(apic, 0x10 + 2 * i);
        }
    }
    spin_unlock_irqrestore(&ioapic_lock, flags);

    return 0;
}

int ioapic_resume(void)
{
    struct IO_APIC_route_entry *entry;
    unsigned long flags;
    union IO_APIC_reg_00 reg_00;
    int i,apic;
    
    if (ioapic_pm_state == NULL){
        printk("Cannot resume ioapic due to lack of memory\n");
        return 1;
    }
    
    entry = ioapic_pm_state;

    spin_lock_irqsave(&ioapic_lock, flags);
    for (apic = 0; apic < nr_ioapics; apic++){
        reg_00.raw = io_apic_read(apic, 0);
        if (reg_00.bits.ID != mp_ioapics[apic].mpc_apicid) {
            reg_00.bits.ID = mp_ioapics[apic].mpc_apicid;
            io_apic_write(apic, 0, reg_00.raw);
        }
        for (i = 0; i < nr_ioapic_registers[apic]; i++, entry++) {
            io_apic_write(apic, 0x11+2*i, *(((int *)entry)+1));
            io_apic_write(apic, 0x10+2*i, *(((int *)entry)+0));
        }
    }
    spin_unlock_irqrestore(&ioapic_lock, flags);

    return 0;
}

/* --------------------------------------------------------------------------
                          ACPI-based IOAPIC Configuration
   -------------------------------------------------------------------------- */

#ifdef CONFIG_ACPI_BOOT

int __init io_apic_get_unique_id (int ioapic, int apic_id)
{
    union IO_APIC_reg_00 reg_00;
    static physid_mask_t apic_id_map = PHYSID_MASK_NONE;
    physid_mask_t tmp;
    unsigned long flags;
    int i = 0;

    /*
     * The P4 platform supports up to 256 APIC IDs on two separate APIC 
     * buses (one for LAPICs, one for IOAPICs), where predecessors only 
     * supports up to 16 on one shared APIC bus.
     * 
     * TBD: Expand LAPIC/IOAPIC support on P4-class systems to take full
     *      advantage of new APIC bus architecture.
     */

    if (physids_empty(apic_id_map))
        apic_id_map = ioapic_phys_id_map(phys_cpu_present_map);

    spin_lock_irqsave(&ioapic_lock, flags);
    reg_00.raw = io_apic_read(ioapic, 0);
    spin_unlock_irqrestore(&ioapic_lock, flags);

    if (apic_id >= get_physical_broadcast()) {
        printk(KERN_WARNING "IOAPIC[%d]: Invalid apic_id %d, trying "
               "%d\n", ioapic, apic_id, reg_00.bits.ID);
        apic_id = reg_00.bits.ID;
    }

    /*
     * Every APIC in a system must have a unique ID or we get lots of nice 
     * 'stuck on smp_invalidate_needed IPI wait' messages.
     */
    if (check_apicid_used(apic_id_map, apic_id)) {

        for (i = 0; i < get_physical_broadcast(); i++) {
            if (!check_apicid_used(apic_id_map, i))
                break;
        }

        if (i == get_physical_broadcast())
            panic("Max apic_id exceeded!\n");

        printk(KERN_WARNING "IOAPIC[%d]: apic_id %d already used, "
               "trying %d\n", ioapic, apic_id, i);

        apic_id = i;
    } 

    tmp = apicid_to_cpu_present(apic_id);
    physids_or(apic_id_map, apic_id_map, tmp);

    if (reg_00.bits.ID != apic_id) {
        reg_00.bits.ID = apic_id;

        spin_lock_irqsave(&ioapic_lock, flags);
        io_apic_write(ioapic, 0, reg_00.raw);
        reg_00.raw = io_apic_read(ioapic, 0);
        spin_unlock_irqrestore(&ioapic_lock, flags);

        /* Sanity check */
        if (reg_00.bits.ID != apic_id) {
            printk("IOAPIC[%d]: Unable to change apic_id!\n", ioapic);
            return -1;
        }
    }

    apic_printk(APIC_VERBOSE, KERN_INFO
                "IOAPIC[%d]: Assigned apic_id %d\n", ioapic, apic_id);

    return apic_id;
}


int __init io_apic_get_version (int ioapic)
{
    union IO_APIC_reg_01	reg_01;
    unsigned long flags;

    spin_lock_irqsave(&ioapic_lock, flags);
    reg_01.raw = io_apic_read(ioapic, 1);
    spin_unlock_irqrestore(&ioapic_lock, flags);

    return reg_01.bits.version;
}


int __init io_apic_get_redir_entries (int ioapic)
{
    union IO_APIC_reg_01	reg_01;
    unsigned long flags;

    spin_lock_irqsave(&ioapic_lock, flags);
    reg_01.raw = io_apic_read(ioapic, 1);
    spin_unlock_irqrestore(&ioapic_lock, flags);

    return reg_01.bits.entries;
}


int io_apic_set_pci_routing (int ioapic, int pin, int irq, int edge_level, int active_high_low)
{
    struct IO_APIC_route_entry entry;
    unsigned long flags;

    if (!IO_APIC_IRQ(irq)) {
        printk(KERN_ERR "IOAPIC[%d]: Invalid reference to IRQ 0\n",
               ioapic);
        return -EINVAL;
    }

    /*
     * Generate a PCI IRQ routing entry and program the IOAPIC accordingly.
     * Note that we mask (disable) IRQs now -- these get enabled when the
     * corresponding device driver registers for this IRQ.
     */

    memset(&entry,0,sizeof(entry));

    entry.delivery_mode = INT_DELIVERY_MODE;
    entry.dest_mode = INT_DEST_MODE;
    entry.dest.logical.logical_dest = cpu_mask_to_apicid(TARGET_CPUS);
    entry.trigger = edge_level;
    entry.polarity = active_high_low;
    entry.mask  = 1;

    /*
     * IRQs < 16 are already in the irq_2_pin[] map
     */
    if (irq >= 16)
        add_pin_to_irq(irq, ioapic, pin);

    entry.vector = assign_irq_vector(irq);

    apic_printk(APIC_DEBUG, KERN_DEBUG "IOAPIC[%d]: Set PCI routing entry "
		"(%d-%d -> 0x%x -> IRQ %d Mode:%i Active:%i)\n", ioapic,
		mp_ioapics[ioapic].mpc_apicid, pin, entry.vector, irq,
		edge_level, active_high_low);

    ioapic_register_intr(irq, entry.vector, edge_level);

    if (!ioapic && (irq < 16))
        disable_8259A_irq(irq);

    spin_lock_irqsave(&ioapic_lock, flags);
    io_apic_write(ioapic, 0x11+2*pin, *(((int *)&entry)+1));
    io_apic_write(ioapic, 0x10+2*pin, *(((int *)&entry)+0));
    set_native_irq_info(entry.vector, TARGET_CPUS);
    spin_unlock_irqrestore(&ioapic_lock, flags);

    return 0;
}

#endif /*CONFIG_ACPI_BOOT*/

static int ioapic_physbase_to_id(unsigned long physbase)
{
    int apic;
    for ( apic = 0; apic < nr_ioapics; apic++ )
        if ( mp_ioapics[apic].mpc_apicaddr == physbase )
            return apic;
    return -EINVAL;
}

int ioapic_guest_read(unsigned long physbase, unsigned int reg, u32 *pval)
{
    int apic;
    unsigned long flags;

    if ( (apic = ioapic_physbase_to_id(physbase)) < 0 )
        return apic;

    spin_lock_irqsave(&ioapic_lock, flags);
    *pval = io_apic_read(apic, reg);
    spin_unlock_irqrestore(&ioapic_lock, flags);

    return 0;
}

#define WARN_BOGUS_WRITE(f, a...)                                       \
    dprintk(XENLOG_INFO, "\n%s: "                                        \
            "apic=%d, pin=%d, old_irq=%d, new_irq=%d\n"                 \
            "%s: old_entry=%08x, new_entry=%08x\n"                      \
            "%s: " f, __FUNCTION__, apic, pin, old_irq, new_irq,        \
            __FUNCTION__, *(u32 *)&old_rte, *(u32 *)&new_rte,           \
            __FUNCTION__ , ##a )

int ioapic_guest_write(unsigned long physbase, unsigned int reg, u32 val)
{
    int apic, pin, old_irq = -1, new_irq = -1;
    struct IO_APIC_route_entry old_rte = { 0 }, new_rte = { 0 };
    unsigned long flags;

    if ( (apic = ioapic_physbase_to_id(physbase)) < 0 )
        return apic;

    /* Only write to the first half of a route entry. */
    if ( (reg < 0x10) || (reg & 1) )
        return 0;
    
    pin = (reg - 0x10) >> 1;

    /* Write first half from guest; second half is target info. */
    *(u32 *)&new_rte = val;
    new_rte.dest.logical.logical_dest = cpu_mask_to_apicid(TARGET_CPUS);

    /*
     * What about weird destination types?
     *  SMI:    Ignore? Ought to be set up by the BIOS.
     *  NMI:    Ignore? Watchdog functionality is Xen's concern.
     *  INIT:   Definitely ignore: probably a guest OS bug.
     *  ExtINT: Ignore? Linux only asserts this at start of day.
     * For now, print a message and return an error. We can fix up on demand.
     */
    if ( new_rte.delivery_mode > dest_LowestPrio )
    {
        printk("ERROR: Attempt to write weird IOAPIC destination mode!\n");
        printk("       APIC=%d/%d, lo-reg=%x\n", apic, pin, val);
        return -EINVAL;
    }

    /*
     * The guest does not know physical APIC arrangement (flat vs. cluster).
     * Apply genapic conventions for this platform.
     */
    new_rte.delivery_mode = INT_DELIVERY_MODE;
    new_rte.dest_mode     = INT_DEST_MODE;

    spin_lock_irqsave(&ioapic_lock, flags);

    /* Read first (interesting) half of current routing entry. */
    *(u32 *)&old_rte = io_apic_read(apic, 0x10 + 2 * pin);

    /* No change to the first half of the routing entry? Bail quietly. */
    if ( *(u32 *)&old_rte == *(u32 *)&new_rte )
    {
        spin_unlock_irqrestore(&ioapic_lock, flags);
        return 0;
    }

    /* Special delivery modes (SMI,NMI,INIT,ExtInt) should have no vector.  */
    if ( (old_rte.delivery_mode > dest_LowestPrio) && (old_rte.vector != 0) )
    {
        WARN_BOGUS_WRITE("Special delivery mode %d with non-zero vector "
                         "%02x\n", old_rte.delivery_mode, old_rte.vector);
        /* Nobble the vector here as it does not relate to a valid irq. */
        old_rte.vector = 0;
    }

    if ( old_rte.vector >= FIRST_DYNAMIC_VECTOR )
        old_irq = vector_irq[old_rte.vector];
    if ( new_rte.vector >= FIRST_DYNAMIC_VECTOR )
        new_irq = vector_irq[new_rte.vector];

    if ( (old_irq != new_irq) && (old_irq != -1) && IO_APIC_IRQ(old_irq) )
    {
        if ( irq_desc[IO_APIC_VECTOR(old_irq)].action )
        {
            WARN_BOGUS_WRITE("Attempt to remove IO-APIC pin of in-use IRQ!\n");
            spin_unlock_irqrestore(&ioapic_lock, flags);
            return 0;
        }

        remove_pin_at_irq(old_irq, apic, pin);
    }

    if ( (new_irq != -1) && IO_APIC_IRQ(new_irq) )
    {
        if ( irq_desc[IO_APIC_VECTOR(new_irq)].action )
        {
            WARN_BOGUS_WRITE("Attempt to %s IO-APIC pin for in-use IRQ!\n",
                             (old_irq != new_irq) ? "add" : "modify");