]> pilppa.com Git - linux-2.6-omap-h63xx.git/commitdiff
x86: make io_apic_64.c and io_apic_32.c the same
authorYinghai Lu <yhlu.kernel@gmail.com>
Wed, 20 Aug 2008 03:50:41 +0000 (20:50 -0700)
committerIngo Molnar <mingo@elte.hu>
Thu, 16 Oct 2008 14:52:55 +0000 (16:52 +0200)
all the same except INTR_REMAPPING related and ioapic io resource.

Signed-off-by: Yinghai Lu <yhlu.kernel@gmail.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
arch/x86/kernel/io_apic_32.c
arch/x86/kernel/io_apic_64.c

index 48184e126f2cac5dcd1fb2c46d34084e0da21cbe..3ed36041c81ec93905fd05386a3f9f7d96d13bba 100644 (file)
@@ -123,7 +123,6 @@ struct irq_cfg {
        u8 move_in_progress : 1;
 };
 
-
 /* irq_cfg is indexed by the sum of all RTEs in all I/O APICs. */
 static struct irq_cfg irq_cfg_legacy[] __initdata = {
        [0]  = { .irq =  0, .domain = CPU_MASK_ALL, .vector = IRQ0_VECTOR,  },
@@ -391,6 +390,38 @@ static inline void io_apic_modify(unsigned int apic, unsigned int reg, unsigned
        writel(value, &io_apic->data);
 }
 
+#ifdef CONFIG_X86_64
+static bool io_apic_level_ack_pending(unsigned int irq)
+{
+       struct irq_pin_list *entry;
+       unsigned long flags;
+       struct irq_cfg *cfg = irq_cfg(irq);
+
+       spin_lock_irqsave(&ioapic_lock, flags);
+       entry = cfg->irq_2_pin;
+       for (;;) {
+               unsigned int reg;
+               int pin;
+
+               if (!entry)
+                       break;
+               pin = entry->pin;
+               reg = io_apic_read(entry->apic, 0x10 + pin*2);
+               /* Is the remote IRR bit set? */
+               if (reg & IO_APIC_REDIR_REMOTE_IRR) {
+                       spin_unlock_irqrestore(&ioapic_lock, flags);
+                       return true;
+               }
+               if (!entry->next)
+                       break;
+               entry = entry->next;
+       }
+       spin_unlock_irqrestore(&ioapic_lock, flags);
+
+       return false;
+}
+#endif
+
 union entry_union {
        struct { u32 w1, w2; };
        struct IO_APIC_route_entry entry;
@@ -483,17 +514,15 @@ static void set_ioapic_affinity_irq(unsigned int irq, cpumask_t mask)
        unsigned int dest;
        cpumask_t tmp;
 
-       cfg = irq_cfg(irq);
-
        cpus_and(tmp, mask, cpu_online_map);
        if (cpus_empty(tmp))
                return;
 
+       cfg = irq_cfg(irq);
        if (assign_irq_vector(irq, mask))
                return;
 
        cpus_and(tmp, cfg->domain, mask);
-
        dest = cpu_mask_to_apicid(tmp);
        /*
         * Only the high 8 bits are valid.
@@ -572,6 +601,54 @@ static void __init replace_pin_at_irq(unsigned int irq,
                add_pin_to_irq(irq, newapic, newpin);
 }
 
+#ifdef CONFIG_X86_64
+/*
+ * Synchronize the IO-APIC and the CPU by doing
+ * a dummy read from the IO-APIC
+ */
+static inline void io_apic_sync(unsigned int apic)
+{
+       struct io_apic __iomem *io_apic = io_apic_base(apic);
+       readl(&io_apic->data);
+}
+
+#define __DO_ACTION(R, ACTION, FINAL)                                  \
+                                                                       \
+{                                                                      \
+       int pin;                                                        \
+       struct irq_cfg *cfg;                                            \
+       struct irq_pin_list *entry;                                     \
+                                                                       \
+       cfg = irq_cfg(irq);                                             \
+       entry = cfg->irq_2_pin;                                         \
+       for (;;) {                                                      \
+               unsigned int reg;                                       \
+               if (!entry)                                             \
+                       break;                                          \
+               pin = entry->pin;                                       \
+               reg = io_apic_read(entry->apic, 0x10 + R + pin*2);      \
+               reg ACTION;                                             \
+               io_apic_modify(entry->apic, 0x10 + R + pin*2, reg);     \
+               FINAL;                                                  \
+               if (!entry->next)                                       \
+                       break;                                          \
+               entry = entry->next;                                    \
+       }                                                               \
+}
+
+#define DO_ACTION(name,R,ACTION, FINAL)                                        \
+                                                                       \
+       static void name##_IO_APIC_irq (unsigned int irq)               \
+       __DO_ACTION(R, ACTION, FINAL)
+
+/* mask = 1 */
+DO_ACTION(__mask,      0, |= IO_APIC_REDIR_MASKED, io_apic_sync(entry->apic))
+
+/* mask = 0 */
+DO_ACTION(__unmask,    0, &= ~IO_APIC_REDIR_MASKED, )
+
+#else
+
 static void __modify_IO_APIC_irq(unsigned int irq, unsigned long enable, unsigned long disable)
 {
        struct irq_cfg *cfg;
@@ -620,6 +697,8 @@ static void __unmask_and_level_IO_APIC_irq(unsigned int irq)
                                IO_APIC_REDIR_MASKED);
 }
 
+#endif
+
 static void mask_IO_APIC_irq(unsigned int irq)
 {
        unsigned long flags;
@@ -1055,6 +1134,17 @@ void unlock_vector_lock(void)
 
 static int __assign_irq_vector(int irq, cpumask_t mask)
 {
+       /*
+        * NOTE! The local APIC isn't very good at handling
+        * multiple interrupts at the same interrupt level.
+        * As the interrupt level is determined by taking the
+        * vector number and shifting that right by 4, we
+        * want to spread these out a bit so that they don't
+        * all fall in the same interrupt level.
+        *
+        * Also, we've got to be careful not to trash gate
+        * 0x80, because int 0x80 is hm, kind of importantish. ;)
+        */
         static int current_vector = FIRST_DEVICE_VECTOR, current_offset = 0;
         unsigned int old_vector;
         int cpu;
@@ -1095,9 +1185,13 @@ next:
                 }
                 if (unlikely(current_vector == vector))
                         continue;
-               if (vector == SYSCALL_VECTOR)
+#ifdef CONFIG_X86_64
+                if (vector == IA32_SYSCALL_VECTOR)
                         goto next;
-
+#else
+                if (vector == SYSCALL_VECTOR)
+                        goto next;
+#endif
                 for_each_cpu_mask_nr(new_cpu, new_mask)
                         if (per_cpu(vector_irq, new_cpu)[vector] != -1)
                                 goto next;
@@ -1184,6 +1278,7 @@ static struct irq_chip ioapic_chip;
 #define IOAPIC_EDGE    0
 #define IOAPIC_LEVEL   1
 
+#ifdef CONFIG_X86_32
 static inline int IO_APIC_irq_trigger(int irq)
 {
        int apic, idx, pin;
@@ -1200,6 +1295,12 @@ static inline int IO_APIC_irq_trigger(int irq)
         */
        return 0;
 }
+#else
+static inline int IO_APIC_irq_trigger(int irq)
+{
+        return 1;
+}
+#endif
 
 static void ioapic_register_intr(int irq, unsigned long trigger)
 {
@@ -1212,15 +1313,18 @@ static void ioapic_register_intr(int irq, unsigned long trigger)
                desc = irq_to_desc_alloc(irq);
 
        if ((trigger == IOAPIC_AUTO && IO_APIC_irq_trigger(irq)) ||
-           trigger == IOAPIC_LEVEL) {
+           trigger == IOAPIC_LEVEL)
                desc->status |= IRQ_LEVEL;
+       else
+               desc->status &= ~IRQ_LEVEL;
+
+       if ((trigger == IOAPIC_AUTO && IO_APIC_irq_trigger(irq)) ||
+           trigger == IOAPIC_LEVEL)
                set_irq_chip_and_handler_name(irq, &ioapic_chip,
                                         handle_fasteoi_irq, "fasteoi");
-       } else {
-               desc->status &= ~IRQ_LEVEL;
+       else
                set_irq_chip_and_handler_name(irq, &ioapic_chip,
                                         handle_edge_irq, "edge");
-       }
 }
 
 static int setup_ioapic_entry(int apic, int irq,
@@ -1662,7 +1766,6 @@ static void __init enable_IO_APIC(void)
                        struct IO_APIC_route_entry entry;
                        entry = ioapic_read_entry(apic, pin);
 
-
                        /* If the interrupt line is enabled and in ExtInt mode
                         * I have found the pin where the i8259 is connected.
                         */
@@ -2012,6 +2115,60 @@ static void ack_apic_edge(unsigned int irq)
        ack_APIC_irq();
 }
 
+#ifdef CONFIG_X86_64
+static void ack_apic_level(unsigned int irq)
+{
+        int do_unmask_irq = 0;
+
+        irq_complete_move(irq);
+#ifdef CONFIG_GENERIC_PENDING_IRQ
+        /* If we are moving the irq we need to mask it */
+        if (unlikely(desc->status & IRQ_MOVE_PENDING)) {
+                do_unmask_irq = 1;
+                mask_IO_APIC_irq(irq);
+        }
+#endif
+
+        /*
+         * We must acknowledge the irq before we move it or the acknowledge will
+         * not propagate properly.
+         */
+        ack_APIC_irq();
+
+        /* Now we can move and renable the irq */
+        if (unlikely(do_unmask_irq)) {
+                /* Only migrate the irq if the ack has been received.
+                 *
+                 * On rare occasions the broadcast level triggered ack gets
+                 * delayed going to ioapics, and if we reprogram the
+                 * vector while Remote IRR is still set the irq will never
+                 * fire again.
+                 *
+                 * To prevent this scenario we read the Remote IRR bit
+                 * of the ioapic.  This has two effects.
+                 * - On any sane system the read of the ioapic will
+                 *   flush writes (and acks) going to the ioapic from
+                 *   this cpu.
+                 * - We get to see if the ACK has actually been delivered.
+                 *
+                 * Based on failed experiments of reprogramming the
+                 * ioapic entry from outside of irq context starting
+                 * with masking the ioapic entry and then polling until
+                 * Remote IRR was clear before reprogramming the
+                 * ioapic I don't trust the Remote IRR bit to be
+                 * completey accurate.
+                 *
+                 * However there appears to be no other way to plug
+                 * this race, so if the Remote IRR bit is not
+                 * accurate and is causing problems then it is a hardware bug
+                 * and you can go talk to the chipset vendor about it.
+                 */
+                if (!io_apic_level_ack_pending(irq))
+                        move_masked_irq(irq, desc);
+                unmask_IO_APIC_irq(irq);
+        }
+}
+#else
 atomic_t irq_mis_count;
 static void ack_apic_level(unsigned int irq)
 {
@@ -2053,6 +2210,7 @@ static void ack_apic_level(unsigned int irq)
                spin_unlock(&ioapic_lock);
        }
 }
+#endif
 
 static struct irq_chip ioapic_chip __read_mostly = {
        .name           = "IO-APIC",
@@ -2224,7 +2382,7 @@ static inline void __init unlock_ExtINT_logic(void)
 }
 
 static int disable_timer_pin_1 __initdata;
-
+/* Actually the next is obsolete, but keep it for paranoid reasons -AK */
 static int __init parse_disable_timer_pin_1(char *arg)
 {
        disable_timer_pin_1 = 1;
@@ -2244,9 +2402,9 @@ static inline void __init check_timer(void)
 {
        struct irq_cfg *cfg = irq_cfg(0);
        int apic1, pin1, apic2, pin2;
-       int no_pin1 = 0;
-       unsigned int ver;
        unsigned long flags;
+       unsigned int ver;
+       int no_pin1 = 0;
 
        local_irq_save(flags);
 
@@ -2550,6 +2708,7 @@ unsigned int create_irq_nr(unsigned int irq_want)
                cfg_new = irq_cfg(new);
                if (cfg_new && cfg_new->vector != 0)
                        continue;
+               /* check if need to create one */
                if (!cfg_new)
                        cfg_new = irq_cfg_alloc(new);
                if (__assign_irq_vector(new, TARGET_CPUS) == 0)
@@ -2720,6 +2879,32 @@ int arch_setup_msi_irq(struct pci_dev *dev, struct msi_desc *desc)
        return 0;
 }
 
+int arch_setup_msi_irqs(struct pci_dev *dev, int nvec, int type)
+{
+        unsigned int irq;
+        int ret, sub_handle;
+        struct msi_desc *desc;
+        unsigned int irq_want;
+
+        irq_want = build_irq_for_pci_dev(dev) + 0x100;
+        sub_handle = 0;
+        list_for_each_entry(desc, &dev->msi_list, list) {
+                irq = create_irq_nr(irq_want--);
+                if (irq == 0)
+                        return -1;
+                ret = setup_msi_irq(dev, desc, irq);
+                if (ret < 0)
+                        goto error;
+                sub_handle++;
+        }
+        return 0;
+
+error:
+        destroy_irq(irq);
+        return ret;
+}
+
+
 void arch_teardown_msi_irq(unsigned int irq)
 {
        destroy_irq(irq);
index b70fd82321856bcc6e7bf8ae6b938ff12a9a29c3..940c4167b32541589d3a96a0cd4f73f95f65d52a 100644 (file)
@@ -94,18 +94,22 @@ struct mp_config_intsrc mp_irqs[MAX_IRQ_SOURCES];
 /* # of MP IRQ source entries */
 int mp_irq_entries;
 
+#if defined (CONFIG_MCA) || defined (CONFIG_EISA)
+int mp_bus_id_to_type[MAX_MP_BUSSES];
+#endif
+
 DECLARE_BITMAP(mp_bus_not_pci, MAX_MP_BUSSES);
 
 int skip_ioapic_setup;
 
 static int __init parse_noapic(char *str)
 {
+       /* disable IO-APIC */
        disable_ioapic_setup();
        return 0;
 }
 early_param("noapic", parse_noapic);
 
-
 struct irq_cfg;
 struct irq_pin_list;
 struct irq_cfg {
@@ -374,6 +378,8 @@ static inline void io_apic_write(unsigned int apic, unsigned int reg, unsigned i
 /*
  * Re-write a value: to be used for read-modify-write
  * cycles where the read already set up the index register.
+ *
+ * Older SiS APIC requires we rewrite the index register
  */
 static inline void io_apic_modify(unsigned int apic, unsigned int reg, unsigned int value)
 {
@@ -383,6 +389,7 @@ static inline void io_apic_modify(unsigned int apic, unsigned int reg, unsigned
        writel(value, &io_apic->data);
 }
 
+#ifdef CONFIG_X86_64
 static bool io_apic_level_ack_pending(unsigned int irq)
 {
        struct irq_pin_list *entry;
@@ -412,6 +419,7 @@ static bool io_apic_level_ack_pending(unsigned int irq)
 
        return false;
 }
+#endif
 
 union entry_union {
        struct { u32 w1, w2; };
@@ -509,7 +517,7 @@ static int assign_irq_vector(int irq, cpumask_t mask);
 
 static void set_ioapic_affinity_irq(unsigned int irq, cpumask_t mask)
 {
-       struct irq_cfg *cfg = irq_cfg(irq);
+       struct irq_cfg *cfg;
        unsigned long flags;
        unsigned int dest;
        cpumask_t tmp;
@@ -519,12 +527,12 @@ static void set_ioapic_affinity_irq(unsigned int irq, cpumask_t mask)
        if (cpus_empty(tmp))
                return;
 
+       cfg = irq_cfg(irq);
        if (assign_irq_vector(irq, mask))
                return;
 
        cpus_and(tmp, cfg->domain, mask);
        dest = cpu_mask_to_apicid(tmp);
-
        /*
         * Only the high 8 bits are valid.
         */
@@ -536,7 +544,7 @@ static void set_ioapic_affinity_irq(unsigned int irq, cpumask_t mask)
        desc->affinity = mask;
        spin_unlock_irqrestore(&ioapic_lock, flags);
 }
-#endif
+#endif /* CONFIG_SMP */
 
 /*
  * The common case is 1:1 IRQ<->pin mappings. Sometimes there are
@@ -602,6 +610,7 @@ static void __init replace_pin_at_irq(unsigned int irq,
                add_pin_to_irq(irq, newapic, newpin);
 }
 
+#ifdef CONFIG_X86_64
 /*
  * Synchronize the IO-APIC and the CPU by doing
  * a dummy read from the IO-APIC
@@ -647,6 +656,58 @@ DO_ACTION(__mask,  0, |= IO_APIC_REDIR_MASKED, io_apic_sync(entry->apic))
 /* mask = 0 */
 DO_ACTION(__unmask,    0, &= ~IO_APIC_REDIR_MASKED, )
 
+#else
+
+static void __modify_IO_APIC_irq(unsigned int irq, unsigned long enable, unsigned long disable)
+{
+       struct irq_cfg *cfg;
+       struct irq_pin_list *entry;
+       unsigned int pin, reg;
+
+       cfg = irq_cfg(irq);
+       entry = cfg->irq_2_pin;
+       for (;;) {
+               if (!entry)
+                       break;
+               pin = entry->pin;
+               reg = io_apic_read(entry->apic, 0x10 + pin*2);
+               reg &= ~disable;
+               reg |= enable;
+               io_apic_modify(entry->apic, 0x10 + pin*2, reg);
+               if (!entry->next)
+                       break;
+               entry = entry->next;
+       }
+}
+
+/* mask = 1 */
+static void __mask_IO_APIC_irq(unsigned int irq)
+{
+       __modify_IO_APIC_irq(irq, IO_APIC_REDIR_MASKED, 0);
+}
+
+/* mask = 0 */
+static void __unmask_IO_APIC_irq(unsigned int irq)
+{
+       __modify_IO_APIC_irq(irq, 0, IO_APIC_REDIR_MASKED);
+}
+
+/* mask = 1, trigger = 0 */
+static void __mask_and_edge_IO_APIC_irq(unsigned int irq)
+{
+       __modify_IO_APIC_irq(irq, IO_APIC_REDIR_MASKED,
+                               IO_APIC_REDIR_LEVEL_TRIGGER);
+}
+
+/* mask = 0, trigger = 1 */
+static void __unmask_and_level_IO_APIC_irq(unsigned int irq)
+{
+       __modify_IO_APIC_irq(irq, IO_APIC_REDIR_LEVEL_TRIGGER,
+                               IO_APIC_REDIR_MASKED);
+}
+
+#endif
+
 static void mask_IO_APIC_irq (unsigned int irq)
 {
        unsigned long flags;
@@ -688,6 +749,64 @@ static void clear_IO_APIC (void)
                        clear_IO_APIC_pin(apic, pin);
 }
 
+#if !defined(CONFIG_SMP) && defined(CONFIG_X86_32)
+void send_IPI_self(int vector)
+{
+       unsigned int cfg;
+
+       /*
+        * Wait for idle.
+        */
+       apic_wait_icr_idle();
+       cfg = APIC_DM_FIXED | APIC_DEST_SELF | vector | APIC_DEST_LOGICAL;
+       /*
+        * Send the IPI. The write to APIC_ICR fires this off.
+        */
+       apic_write(APIC_ICR, cfg);
+}
+#endif /* !CONFIG_SMP && CONFIG_X86_32*/
+
+#ifdef CONFIG_X86_32
+/*
+ * support for broken MP BIOSs, enables hand-redirection of PIRQ0-7 to
+ * specific CPU-side IRQs.
+ */
+
+#define MAX_PIRQS 8
+static int pirq_entries [MAX_PIRQS];
+static int pirqs_enabled;
+
+static int __init ioapic_pirq_setup(char *str)
+{
+       int i, max;
+       int ints[MAX_PIRQS+1];
+
+       get_options(str, ARRAY_SIZE(ints), ints);
+
+       for (i = 0; i < MAX_PIRQS; i++)
+               pirq_entries[i] = -1;
+
+       pirqs_enabled = 1;
+       apic_printk(APIC_VERBOSE, KERN_INFO
+                       "PIRQ redirection, working around broken MP-BIOS.\n");
+       max = MAX_PIRQS;
+       if (ints[0] < MAX_PIRQS)
+               max = ints[0];
+
+       for (i = 0; i < max; i++) {
+               apic_printk(APIC_VERBOSE, KERN_DEBUG
+                               "... PIRQ%d -> IRQ %d\n", i, ints[i+1]);
+               /*
+                * PIRQs are mapped upside down, usually.
+                */
+               pirq_entries[MAX_PIRQS-i-1] = ints[i+1];
+       }
+       return 1;
+}
+
+__setup("pirq=", ioapic_pirq_setup);
+#endif /* CONFIG_X86_32 */
+
 #ifdef CONFIG_INTR_REMAP
 /* I/O APIC RTE contents at the OS boot up */
 static struct IO_APIC_route_entry *early_ioapic_entries[MAX_IO_APICS];
@@ -861,18 +980,51 @@ int IO_APIC_get_PCI_irq_vector(int bus, int slot, int pin)
        return best_guess;
 }
 
+EXPORT_SYMBOL(IO_APIC_get_PCI_irq_vector);
+
+#if defined(CONFIG_EISA) || defined(CONFIG_MCA)
+/*
+ * EISA Edge/Level control register, ELCR
+ */
+static int EISA_ELCR(unsigned int irq)
+{
+       if (irq < 16) {
+               unsigned int port = 0x4d0 + (irq >> 3);
+               return (inb(port) >> (irq & 7)) & 1;
+       }
+       apic_printk(APIC_VERBOSE, KERN_INFO
+                       "Broken MPtable reports ISA irq %d\n", irq);
+       return 0;
+}
+
+#endif
+
 /* ISA interrupts are always polarity zero edge triggered,
  * when listed as conforming in the MP table. */
 
 #define default_ISA_trigger(idx)       (0)
 #define default_ISA_polarity(idx)      (0)
 
+/* EISA interrupts are always polarity zero and can be edge or level
+ * trigger depending on the ELCR value.  If an interrupt is listed as
+ * EISA conforming in the MP table, that means its trigger type must
+ * be read in from the ELCR */
+
+#define default_EISA_trigger(idx)      (EISA_ELCR(mp_irqs[idx].mp_srcbusirq))
+#define default_EISA_polarity(idx)     default_ISA_polarity(idx)
+
 /* PCI interrupts are always polarity one level triggered,
  * when listed as conforming in the MP table. */
 
 #define default_PCI_trigger(idx)       (1)
 #define default_PCI_polarity(idx)      (1)
 
+/* MCA interrupts are always polarity zero level triggered,
+ * when listed as conforming in the MP table. */
+
+#define default_MCA_trigger(idx)       (1)
+#define default_MCA_polarity(idx)      default_ISA_polarity(idx)
+
 static int MPBIOS_polarity(int idx)
 {
        int bus = mp_irqs[idx].mp_srcbus;
@@ -930,6 +1082,36 @@ static int MPBIOS_trigger(int idx)
                                trigger = default_ISA_trigger(idx);
                        else
                                trigger = default_PCI_trigger(idx);
+#if defined(CONFIG_EISA) || defined(CONFIG_MCA)
+                       switch (mp_bus_id_to_type[bus]) {
+                               case MP_BUS_ISA: /* ISA pin */
+                               {
+                                       /* set before the switch */
+                                       break;
+                               }
+                               case MP_BUS_EISA: /* EISA pin */
+                               {
+                                       trigger = default_EISA_trigger(idx);
+                                       break;
+                               }
+                               case MP_BUS_PCI: /* PCI pin */
+                               {
+                                       /* set before the switch */
+                                       break;
+                               }
+                               case MP_BUS_MCA: /* MCA pin */
+                               {
+                                       trigger = default_MCA_trigger(idx);
+                                       break;
+                               }
+                               default:
+                               {
+                                       printk(KERN_WARNING "broken BIOS!!\n");
+                                       trigger = 1;
+                                       break;
+                               }
+                       }
+#endif
                        break;
                case 1: /* edge */
                {
@@ -967,6 +1149,7 @@ static inline int irq_trigger(int idx)
        return MPBIOS_trigger(idx);
 }
 
+int (*ioapic_renumber_irq)(int ioapic, int irq);
 static int pin_2_irq(int idx, int apic, int pin)
 {
        int irq, i;
@@ -988,7 +1171,32 @@ static int pin_2_irq(int idx, int apic, int pin)
                while (i < apic)
                        irq += nr_ioapic_registers[i++];
                irq += pin;
+                /*
+                 * For MPS mode, so far only needed by ES7000 platform
+                 */
+                if (ioapic_renumber_irq)
+                        irq = ioapic_renumber_irq(apic, irq);
        }
+
+#ifdef CONFIG_X86_32
+       /*
+        * PCI IRQ command line redirection. Yes, limits are hardcoded.
+        */
+       if ((pin >= 16) && (pin <= 23)) {
+               if (pirq_entries[pin-16] != -1) {
+                       if (!pirq_entries[pin-16]) {
+                               apic_printk(APIC_VERBOSE, KERN_DEBUG
+                                               "disabling PIRQ%d\n", pin-16);
+                       } else {
+                               irq = pirq_entries[pin-16];
+                               apic_printk(APIC_VERBOSE, KERN_DEBUG
+                                               "using PIRQ%d -> IRQ %d\n",
+                                               pin-16, irq);
+                       }
+               }
+       }
+#endif
+
        return irq;
 }
 
@@ -1058,8 +1266,13 @@ next:
                }
                if (unlikely(current_vector == vector))
                        continue;
+#ifdef CONFIG_X86_64
                if (vector == IA32_SYSCALL_VECTOR)
                        goto next;
+#else
+               if (vector == SYSCALL_VECTOR)
+                       goto next;
+#endif
                for_each_cpu_mask_nr(new_cpu, new_mask)
                        if (per_cpu(vector_irq, new_cpu)[vector] != -1)
                                goto next;
@@ -1140,6 +1353,34 @@ static struct irq_chip ioapic_chip;
 static struct irq_chip ir_ioapic_chip;
 #endif
 
+#define IOAPIC_AUTO     -1
+#define IOAPIC_EDGE     0
+#define IOAPIC_LEVEL    1
+
+#ifdef CONFIG_X86_32
+static inline int IO_APIC_irq_trigger(int irq)
+{
+        int apic, idx, pin;
+
+        for (apic = 0; apic < nr_ioapics; apic++) {
+                for (pin = 0; pin < nr_ioapic_registers[apic]; pin++) {
+                        idx = find_irq_entry(apic, pin, mp_INT);
+                        if ((idx != -1) && (irq == pin_2_irq(idx, apic, pin)))
+                                return irq_trigger(idx);
+                }
+        }
+        /*
+         * nonexistent IRQs are edge default
+         */
+        return 0;
+}
+#else
+static inline int IO_APIC_irq_trigger(int irq)
+{
+       return 1;
+}
+#endif
+
 static void ioapic_register_intr(int irq, unsigned long trigger)
 {
        struct irq_desc *desc;
@@ -1150,7 +1391,8 @@ static void ioapic_register_intr(int irq, unsigned long trigger)
        else
                desc = irq_to_desc_alloc(irq);
 
-       if (trigger)
+       if ((trigger == IOAPIC_AUTO && IO_APIC_irq_trigger(irq)) ||
+           trigger == IOAPIC_LEVEL)
                desc->status |= IRQ_LEVEL;
        else
                desc->status &= ~IRQ_LEVEL;
@@ -1168,7 +1410,8 @@ static void ioapic_register_intr(int irq, unsigned long trigger)
                return;
        }
 #endif
-       if (trigger)
+       if ((trigger == IOAPIC_AUTO && IO_APIC_irq_trigger(irq)) ||
+           trigger == IOAPIC_LEVEL)
                set_irq_chip_and_handler_name(irq, &ioapic_chip,
                                              handle_fasteoi_irq,
                                              "fasteoi");
@@ -1303,6 +1546,10 @@ static void __init setup_IO_APIC_irqs(void)
                }
 
                irq = pin_2_irq(idx, apic, pin);
+#ifdef CONFIG_X86_32
+                if (multi_timer_check(apic, irq))
+                        continue;
+#endif
                add_pin_to_irq(irq, apic, pin);
 
                setup_IO_APIC_irq(apic, pin, irq,
@@ -1360,6 +1607,7 @@ __apicdebuginit(void) print_IO_APIC(void)
        union IO_APIC_reg_00 reg_00;
        union IO_APIC_reg_01 reg_01;
        union IO_APIC_reg_02 reg_02;
+       union IO_APIC_reg_03 reg_03;
        unsigned long flags;
        struct irq_cfg *cfg;
 
@@ -1384,6 +1632,8 @@ __apicdebuginit(void) print_IO_APIC(void)
        reg_01.raw = io_apic_read(apic, 1);
        if (reg_01.bits.version >= 0x10)
                reg_02.raw = io_apic_read(apic, 2);
+        if (reg_01.bits.version >= 0x20)
+                reg_03.raw = io_apic_read(apic, 3);
        spin_unlock_irqrestore(&ioapic_lock, flags);
 
        printk("\n");
@@ -1399,11 +1649,27 @@ __apicdebuginit(void) print_IO_APIC(void)
        printk(KERN_DEBUG ".......     : PRQ implemented: %X\n", reg_01.bits.PRQ);
        printk(KERN_DEBUG ".......     : IO APIC version: %04X\n", reg_01.bits.version);
 
-       if (reg_01.bits.version >= 0x10) {
+       /*
+        * Some Intel chipsets with IO APIC VERSION of 0x1? don't have reg_02,
+        * but the value of reg_02 is read as the previous read register
+        * value, so ignore it if reg_02 == reg_01.
+        */
+       if (reg_01.bits.version >= 0x10 && reg_02.raw != reg_01.raw) {
                printk(KERN_DEBUG ".... register #02: %08X\n", reg_02.raw);
                printk(KERN_DEBUG ".......     : arbitration: %02X\n", reg_02.bits.arbitration);
        }
 
+       /*
+        * Some Intel chipsets with IO APIC VERSION of 0x2? don't have reg_02
+        * or reg_03, but the value of reg_0[23] is read as the previous read
+        * register value, so ignore it if reg_03 == reg_0[12].
+        */
+       if (reg_01.bits.version >= 0x20 && reg_03.raw != reg_02.raw &&
+           reg_03.raw != reg_01.raw) {
+               printk(KERN_DEBUG ".... register #03: %08X\n", reg_03.raw);
+               printk(KERN_DEBUG ".......     : Boot DT    : %X\n", reg_03.bits.boot_DT);
+       }
+
        printk(KERN_DEBUG ".... IRQ redirection table:\n");
 
        printk(KERN_DEBUG " NR Dst Mask Trig IRR Pol"
@@ -1475,7 +1741,7 @@ __apicdebuginit(void) print_APIC_bitfield(int base)
 __apicdebuginit(void) print_local_APIC(void *dummy)
 {
        unsigned int v, ver, maxlvt;
-       unsigned long icr;
+       u64 icr;
 
        if (apic_verbosity == APIC_QUIET)
                return;
@@ -1492,11 +1758,13 @@ __apicdebuginit(void) print_local_APIC(void *dummy)
        v = apic_read(APIC_TASKPRI);
        printk(KERN_DEBUG "... APIC TASKPRI: %08x (%02x)\n", v, v & APIC_TPRI_MASK);
 
-       v = apic_read(APIC_ARBPRI);
-       printk(KERN_DEBUG "... APIC ARBPRI: %08x (%02x)\n", v,
-               v & APIC_ARBPRI_MASK);
-       v = apic_read(APIC_PROCPRI);
-       printk(KERN_DEBUG "... APIC PROCPRI: %08x\n", v);
+       if (APIC_INTEGRATED(ver)) {                     /* !82489DX */
+               v = apic_read(APIC_ARBPRI);
+               printk(KERN_DEBUG "... APIC ARBPRI: %08x (%02x)\n", v,
+                       v & APIC_ARBPRI_MASK);
+               v = apic_read(APIC_PROCPRI);
+               printk(KERN_DEBUG "... APIC PROCPRI: %08x\n", v);
+       }
 
        v = apic_read(APIC_EOI);
        printk(KERN_DEBUG "... APIC EOI: %08x\n", v);
@@ -1516,8 +1784,13 @@ __apicdebuginit(void) print_local_APIC(void *dummy)
        printk(KERN_DEBUG "... APIC IRR field:\n");
        print_APIC_bitfield(APIC_IRR);
 
-       v = apic_read(APIC_ESR);
-       printk(KERN_DEBUG "... APIC ESR: %08x\n", v);
+       if (APIC_INTEGRATED(ver)) {             /* !82489DX */
+               if (maxlvt > 3)         /* Due to the Pentium erratum 3AP. */
+                       apic_write(APIC_ESR, 0);
+
+               v = apic_read(APIC_ESR);
+               printk(KERN_DEBUG "... APIC ESR: %08x\n", v);
+       }
 
        icr = apic_icr_read();
        printk(KERN_DEBUG "... APIC ICR: %08x\n", (u32)icr);
@@ -1608,6 +1881,13 @@ void __init enable_IO_APIC(void)
        int apic;
        unsigned long flags;
 
+#ifdef CONFIG_X86_32
+       int i;
+       if (!pirqs_enabled)
+               for (i = 0; i < MAX_PIRQS; i++)
+                       pirq_entries[i] = -1;
+#endif
+
        /*
         * The number of IO-APIC IRQ registers (== #pins):
         */
@@ -1636,6 +1916,10 @@ void __init enable_IO_APIC(void)
        }
  found_i8259:
        /* Look to see what if the MP table has reported the ExtINT */
+       /* If we could not find the appropriate pin by looking at the ioapic
+        * the i8259 probably is not connected the ioapic but give the
+        * mptable a chance anyway.
+        */
        i8259_pin  = find_isa_irq_pin(0, mp_ExtINT);
        i8259_apic = find_isa_irq_apic(0, mp_ExtINT);
        /* Trust the MP table if nothing is setup in the hardware */
@@ -1695,6 +1979,122 @@ void disable_IO_APIC(void)
        disconnect_bsp_APIC(ioapic_i8259.pin != -1);
 }
 
+#ifdef CONFIG_X86_32
+/*
+ * function to set the IO-APIC physical IDs based on the
+ * values stored in the MPC table.
+ *
+ * by Matt Domsch <Matt_Domsch@dell.com>  Tue Dec 21 12:25:05 CST 1999
+ */
+
+static void __init setup_ioapic_ids_from_mpc(void)
+{
+       union IO_APIC_reg_00 reg_00;
+       physid_mask_t phys_id_present_map;
+       int apic;
+       int i;
+       unsigned char old_id;
+       unsigned long flags;
+
+       if (x86_quirks->setup_ioapic_ids && x86_quirks->setup_ioapic_ids())
+               return;
+
+       /*
+        * Don't check I/O APIC IDs for xAPIC systems.  They have
+        * no meaning without the serial APIC bus.
+        */
+       if (!(boot_cpu_data.x86_vendor == X86_VENDOR_INTEL)
+               || APIC_XAPIC(apic_version[boot_cpu_physical_apicid]))
+               return;
+       /*
+        * This is broken; anything with a real cpu count has to
+        * circumvent this idiocy regardless.
+        */
+       phys_id_present_map = ioapic_phys_id_map(phys_cpu_present_map);
+
+       /*
+        * Set the IOAPIC ID to the value stored in the MPC table.
+        */
+       for (apic = 0; apic < nr_ioapics; apic++) {
+
+               /* Read the register 0 value */
+               spin_lock_irqsave(&ioapic_lock, flags);
+               reg_00.raw = io_apic_read(apic, 0);
+               spin_unlock_irqrestore(&ioapic_lock, flags);
+
+               old_id = mp_ioapics[apic].mp_apicid;
+
+               if (mp_ioapics[apic].mp_apicid >= get_physical_broadcast()) {
+                       printk(KERN_ERR "BIOS bug, IO-APIC#%d ID is %d in the MPC table!...\n",
+                               apic, mp_ioapics[apic].mp_apicid);
+                       printk(KERN_ERR "... fixing up to %d. (tell your hw vendor)\n",
+                               reg_00.bits.ID);
+                       mp_ioapics[apic].mp_apicid = reg_00.bits.ID;
+               }
+
+               /*
+                * Sanity check, is the ID really free? 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(phys_id_present_map,
+                                       mp_ioapics[apic].mp_apicid)) {
+                       printk(KERN_ERR "BIOS bug, IO-APIC#%d ID %d is already used!...\n",
+                               apic, mp_ioapics[apic].mp_apicid);
+                       for (i = 0; i < get_physical_broadcast(); i++)
+                               if (!physid_isset(i, phys_id_present_map))
+                                       break;
+                       if (i >= get_physical_broadcast())
+                               panic("Max APIC ID exceeded!\n");
+                       printk(KERN_ERR "... fixing up to %d. (tell your hw vendor)\n",
+                               i);
+                       physid_set(i, phys_id_present_map);
+                       mp_ioapics[apic].mp_apicid = i;
+               } else {
+                       physid_mask_t tmp;
+                       tmp = apicid_to_cpu_present(mp_ioapics[apic].mp_apicid);
+                       apic_printk(APIC_VERBOSE, "Setting %d in the "
+                                       "phys_id_present_map\n",
+                                       mp_ioapics[apic].mp_apicid);
+                       physids_or(phys_id_present_map, phys_id_present_map, tmp);
+               }
+
+
+               /*
+                * We need to adjust the IRQ routing table
+                * if the ID changed.
+                */
+               if (old_id != mp_ioapics[apic].mp_apicid)
+                       for (i = 0; i < mp_irq_entries; i++)
+                               if (mp_irqs[i].mp_dstapic == old_id)
+                                       mp_irqs[i].mp_dstapic
+                                               = mp_ioapics[apic].mp_apicid;
+
+               /*
+                * Read the right value from the MPC table and
+                * write it into the ID register.
+                */
+               apic_printk(APIC_VERBOSE, KERN_INFO
+                       "...changing IO-APIC physical APIC ID to %d ...",
+                       mp_ioapics[apic].mp_apicid);
+
+               reg_00.bits.ID = mp_ioapics[apic].mp_apicid;
+               spin_lock_irqsave(&ioapic_lock, flags);
+
+               /*
+                * Sanity check
+                */
+               spin_lock_irqsave(&ioapic_lock, flags);
+               reg_00.raw = io_apic_read(apic, 0);
+               spin_unlock_irqrestore(&ioapic_lock, flags);
+               if (reg_00.bits.ID != mp_ioapics[apic].mp_apicid)
+                       printk("could not set ID!\n");
+               else
+                       apic_printk(APIC_VERBOSE, " ok.\n");
+       }
+}
+#endif
+
 int no_timer_check __initdata;
 
 static int __init notimercheck(char *s)
@@ -1780,8 +2180,10 @@ static unsigned int startup_ioapic_irq(unsigned int irq)
        return was_pending;
 }
 
+#ifdef CONFIG_X86_64
 static int ioapic_retrigger_irq(unsigned int irq)
 {
+
        struct irq_cfg *cfg = irq_cfg(irq);
        unsigned long flags;
 
@@ -1791,6 +2193,14 @@ static int ioapic_retrigger_irq(unsigned int irq)
 
        return 1;
 }
+#else
+static int ioapic_retrigger_irq(unsigned int irq)
+{
+        send_IPI_self(irq_cfg(irq)->vector);
+
+        return 1;
+}
+#endif
 
 /*
  * Level and edge triggered IO-APIC interrupts need different handling,
@@ -1952,7 +2362,9 @@ asmlinkage void smp_irq_move_cleanup_interrupt(void)
 {
        unsigned vector, me;
        ack_APIC_irq();
+#ifdef CONFIG_X86_64
        exit_idle();
+#endif
        irq_enter();
 
        me = smp_processor_id();
@@ -2024,6 +2436,7 @@ static void ack_apic_edge(unsigned int irq)
        ack_APIC_irq();
 }
 
+#ifdef CONFIG_X86_64
 static void ack_apic_level(unsigned int irq)
 {
        int do_unmask_irq = 0;
@@ -2076,6 +2489,49 @@ static void ack_apic_level(unsigned int irq)
                unmask_IO_APIC_irq(irq);
        }
 }
+#else
+atomic_t irq_mis_count;
+static void ack_apic_level(unsigned int irq)
+{
+       unsigned long v;
+       int i;
+
+       irq_complete_move(irq);
+       move_native_irq(irq);
+       /*
+       * It appears there is an erratum which affects at least version 0x11
+       * of I/O APIC (that's the 82093AA and cores integrated into various
+       * chipsets).  Under certain conditions a level-triggered interrupt is
+       * erroneously delivered as edge-triggered one but the respective IRR
+       * bit gets set nevertheless.  As a result the I/O unit expects an EOI
+       * message but it will never arrive and further interrupts are blocked
+       * from the source.  The exact reason is so far unknown, but the
+       * phenomenon was observed when two consecutive interrupt requests
+       * from a given source get delivered to the same CPU and the source is
+       * temporarily disabled in between.
+       *
+       * A workaround is to simulate an EOI message manually.  We achieve it
+       * by setting the trigger mode to edge and then to level when the edge
+       * trigger mode gets detected in the TMR of a local APIC for a
+       * level-triggered interrupt.  We mask the source for the time of the
+       * operation to prevent an edge-triggered interrupt escaping meanwhile.
+       * The idea is from Manfred Spraul.  --macro
+       */
+       i = irq_cfg(irq)->vector;
+
+       v = apic_read(APIC_TMR + ((i & ~0x1f) >> 1));
+
+       ack_APIC_irq();
+
+       if (!(v & (1 << (i & 0x1f)))) {
+               atomic_inc(&irq_mis_count);
+               spin_lock(&ioapic_lock);
+               __mask_and_edge_IO_APIC_irq(irq);
+               __unmask_and_level_IO_APIC_irq(irq);
+               spin_unlock(&ioapic_lock);
+       }
+}
+#endif
 
 static struct irq_chip ioapic_chip __read_mostly = {
        .name           = "IO-APIC",
@@ -2141,20 +2597,24 @@ static inline void init_IO_APIC_traps(void)
        }
 }
 
-static void unmask_lapic_irq(unsigned int irq)
+/*
+ * The local APIC irq-chip implementation:
+ */
+
+static void mask_lapic_irq(unsigned int irq)
 {
        unsigned long v;
 
        v = apic_read(APIC_LVT0);
-       apic_write(APIC_LVT0, v & ~APIC_LVT_MASKED);
+       apic_write(APIC_LVT0, v APIC_LVT_MASKED);
 }
 
-static void mask_lapic_irq(unsigned int irq)
+static void unmask_lapic_irq(unsigned int irq)
 {
        unsigned long v;
 
        v = apic_read(APIC_LVT0);
-       apic_write(APIC_LVT0, v APIC_LVT_MASKED);
+       apic_write(APIC_LVT0, v & ~APIC_LVT_MASKED);
 }
 
 static void ack_lapic_irq (unsigned int irq)
@@ -2182,19 +2642,19 @@ static void lapic_register_intr(int irq)
 static void __init setup_nmi(void)
 {
        /*
-        * Dirty trick to enable the NMI watchdog ...
+        * Dirty trick to enable the NMI watchdog ...
         * We put the 8259A master into AEOI mode and
         * unmask on all local APICs LVT0 as NMI.
         *
         * The idea to use the 8259A in AEOI mode ('8259A Virtual Wire')
         * is from Maciej W. Rozycki - so we do not have to EOI from
         * the NMI handler or the timer interrupt.
-        */ 
-       printk(KERN_INFO "activating NMI Watchdog ...");
+        */
+       apic_printk(APIC_VERBOSE, KERN_INFO "activating NMI Watchdog ...");
 
        enable_NMI_through_LVT0();
 
-       printk(" done.\n");
+       apic_printk(APIC_VERBOSE, " done.\n");
 }
 
 /*
@@ -2211,12 +2671,17 @@ static inline void __init unlock_ExtINT_logic(void)
        unsigned char save_control, save_freq_select;
 
        pin  = find_isa_irq_pin(8, mp_INT);
+       if (pin == -1) {
+               WARN_ON_ONCE(1);
+               return;
+       }
        apic = find_isa_irq_apic(8, mp_INT);
-       if (pin == -1)
+       if (apic == -1) {
+               WARN_ON_ONCE(1);
                return;
+       }
 
        entry0 = ioapic_read_entry(apic, pin);
-
        clear_IO_APIC_pin(apic, pin);
 
        memset(&entry1, 0, sizeof(entry1));
@@ -2268,17 +2733,21 @@ int timer_through_8259 __initdata;
  * is so screwy.  Thanks to Brian Perkins for testing/hacking this beast
  * fanatically on his truly buggy board.
  *
- * FIXME: really need to revamp this for modern platforms only.
+ * FIXME: really need to revamp this for all platforms.
  */
 static inline void __init check_timer(void)
 {
        struct irq_cfg *cfg = irq_cfg(0);
        int apic1, pin1, apic2, pin2;
        unsigned long flags;
+       unsigned int ver;
        int no_pin1 = 0;
 
        local_irq_save(flags);
 
+        ver = apic_read(APIC_LVR);
+        ver = GET_APIC_VERSION(ver);
+
        /*
         * get/set the timer IRQ vector:
         */
@@ -2287,10 +2756,18 @@ static inline void __init check_timer(void)
 
        /*
         * As IRQ0 is to be enabled in the 8259A, the virtual
-        * wire has to be disabled in the local APIC.
+        * wire has to be disabled in the local APIC.  Also
+        * timer interrupts need to be acknowledged manually in
+        * the 8259A for the i82489DX when using the NMI
+        * watchdog as that APIC treats NMIs as level-triggered.
+        * The AEOI mode will finish them in the 8259A
+        * automatically.
         */
        apic_write(APIC_LVT0, APIC_LVT_MASKED | APIC_DM_EXTINT);
        init_8259A(1);
+#ifdef CONFIG_X86_32
+       timer_ack = (nmi_watchdog == NMI_IO_APIC && !APIC_INTEGRATED(ver));
+#endif
 
        pin1  = find_isa_irq_pin(0, mp_INT);
        apic1 = find_isa_irq_apic(0, mp_INT);
@@ -2382,6 +2859,9 @@ static inline void __init check_timer(void)
                            "through the IO-APIC - disabling NMI Watchdog!\n");
                nmi_watchdog = NMI_NONE;
        }
+#ifdef CONFIG_X86_32
+       timer_ack = 0;
+#endif
 
        apic_printk(APIC_QUIET, KERN_INFO
                    "...trying to set up timer as Virtual Wire IRQ...\n");
@@ -2435,19 +2915,29 @@ out:
  * the I/O APIC in all cases now.  No actual device should request
  * it anyway.  --macro
  */
-#define PIC_IRQS       (1<<2)
+#define PIC_IRQS       (1 << PIC_CASCADE_IR)
 
 void __init setup_IO_APIC(void)
 {
 
+#ifdef CONFIG_X86_32
+       enable_IO_APIC();
+#else
        /*
         * calling enable_IO_APIC() is moved to setup_local_APIC for BP
         */
+#endif
 
        io_apic_irqs = ~PIC_IRQS;
 
        apic_printk(APIC_VERBOSE, "ENABLING IO-APIC IRQs\n");
-
+        /*
+         * Set up IO-APIC IRQ routing.
+         */
+#ifdef CONFIG_X86_32
+        if (!acpi_ioapic)
+                setup_ioapic_ids_from_mpc();
+#endif
        sync_Arb_IDs();
        setup_IO_APIC_irqs();
        init_IO_APIC_traps();
@@ -3128,7 +3618,93 @@ int arch_setup_ht_irq(unsigned int irq, struct pci_dev *dev)
 
 #ifdef CONFIG_ACPI
 
-#define IO_APIC_MAX_ID         0xFE
+#ifdef CONFIG_X86_32
+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;
+}
+#endif
 
 int __init io_apic_get_redir_entries (int ioapic)
 {
@@ -3226,6 +3802,7 @@ void __init setup_ioapic_dest(void)
 }
 #endif
 
+#ifdef CONFIG_X86_64
 #define IOAPIC_RESOURCE_NAME_SIZE 11
 
 static struct resource *ioapic_resources;
@@ -3261,36 +3838,56 @@ static struct resource * __init ioapic_setup_resources(void)
 
        return res;
 }
+#endif
 
 void __init ioapic_init_mappings(void)
 {
        unsigned long ioapic_phys, idx = FIX_IO_APIC_BASE_0;
-       struct resource *ioapic_res;
        int i;
+#ifdef CONFIG_X86_64
+       struct resource *ioapic_res;
 
        ioapic_res = ioapic_setup_resources();
+#endif
        for (i = 0; i < nr_ioapics; i++) {
                if (smp_found_config) {
                        ioapic_phys = mp_ioapics[i].mp_apicaddr;
+#ifdef CONFIG_X86_32
+                        if (!ioapic_phys) {
+                                printk(KERN_ERR
+                                       "WARNING: bogus zero IO-APIC "
+                                       "address found in MPTABLE, "
+                                       "disabling IO/APIC support!\n");
+                                smp_found_config = 0;
+                                skip_ioapic_setup = 1;
+                                goto fake_ioapic_page;
+                        }
+#endif
                } else {
+#ifdef CONFIG_X86_32
+fake_ioapic_page:
+#endif
                        ioapic_phys = (unsigned long)
                                alloc_bootmem_pages(PAGE_SIZE);
                        ioapic_phys = __pa(ioapic_phys);
                }
                set_fixmap_nocache(idx, ioapic_phys);
                apic_printk(APIC_VERBOSE,
-                           "mapped IOAPIC to %016lx (%016lx)\n",
+                           "mapped IOAPIC to %08lx (%08lx)\n",
                            __fix_to_virt(idx), ioapic_phys);
                idx++;
 
+#ifdef CONFIG_X86_64
                if (ioapic_res != NULL) {
                        ioapic_res->start = ioapic_phys;
                        ioapic_res->end = ioapic_phys + (4 * 1024) - 1;
                        ioapic_res++;
                }
+#endif
        }
 }
 
+#ifdef CONFIG_X86_64
 static int __init ioapic_insert_resources(void)
 {
        int i;
@@ -3313,4 +3910,4 @@ static int __init ioapic_insert_resources(void)
 /* Insert the IO APIC resources after PCI initialization has occured to handle
  * IO APICS that are mapped in on a BAR in PCI space. */
 late_initcall(ioapic_insert_resources);
-
+#endif