1 files changed, 79 insertions, 52 deletions

diff --git a/arch/x86/kernel/io_apic_64.c b/arch/x86/kernel/io_apic_64.c
index c7c6b005f665..e5ef60303562 100644
--- a/arch/x86/kernel/io_apic_64.c
+++ b/arch/x86/kernel/io_apic_64.c
@@ -61,7 +61,7 @@ struct irq_cfg {
 };
 
 /* irq_cfg is indexed by the sum of all RTEs in all I/O APICs. */
-struct irq_cfg irq_cfg[NR_IRQS] __read_mostly = {
+static struct irq_cfg irq_cfg[NR_IRQS] __read_mostly = {
         [0]  = { .domain = CPU_MASK_ALL, .vector = IRQ0_VECTOR,  },
         [1]  = { .domain = CPU_MASK_ALL, .vector = IRQ1_VECTOR,  },
         [2]  = { .domain = CPU_MASK_ALL, .vector = IRQ2_VECTOR,  },
@@ -90,7 +90,7 @@ static int no_timer_check;
 
 static int disable_timer_pin_1 __initdata;
 
-int timer_over_8254 __initdata = 1;
+int timer_through_8259 __initdata;
 
 /* Where if anywhere is the i8259 connect in external int mode */
 static struct { int pin, apic; } ioapic_i8259 = { -1, -1 };
@@ -183,7 +183,7 @@ static bool io_apic_level_ack_pending(unsigned int irq)
                         break;
                 reg = io_apic_read(entry->apic, 0x10 + pin*2);
                 /* Is the remote IRR bit set? */
-                if ((reg >> 14) & 1) {
+                if (reg & IO_APIC_REDIR_REMOTE_IRR) {
                         spin_unlock_irqrestore(&ioapic_lock, flags);
                         return true;
                 }
@@ -298,7 +298,7 @@ static void __target_IO_APIC_irq(unsigned int irq, unsigned int dest, u8 vector)
                         break;
                 io_apic_write(apic, 0x11 + pin*2, dest);
                 reg = io_apic_read(apic, 0x10 + pin*2);
-                reg &= ~0x000000ff;
+                reg &= ~IO_APIC_REDIR_VECTOR_MASK;
                 reg |= vector;
                 io_apic_modify(apic, reg);
                 if (!entry->next)
@@ -360,16 +360,37 @@ static void add_pin_to_irq(unsigned int irq, int apic, int pin)
         entry->pin = pin;
 }
 
+/*
+ * Reroute an IRQ to a different pin.
+ */
+static void __init replace_pin_at_irq(unsigned int irq,
+                                      int oldapic, int oldpin,
+                                      int newapic, int newpin)
+{
+        struct irq_pin_list *entry = irq_2_pin + irq;
+
+        while (1) {
+                if (entry->apic == oldapic && entry->pin == oldpin) {
+                        entry->apic = newapic;
+                        entry->pin = newpin;
+                }
+                if (!entry->next)
+                        break;
+                entry = irq_2_pin + entry->next;
+        }
+}
+
 
 #define DO_ACTION(name,R,ACTION, FINAL)                                 \
                                                                         \
         static void name##_IO_APIC_irq (unsigned int irq)               \
         __DO_ACTION(R, ACTION, FINAL)
 
-DO_ACTION( __mask,             0, |= 0x00010000, io_apic_sync(entry->apic) )
-                                                /* mask = 1 */
-DO_ACTION( __unmask,           0, &= 0xfffeffff, )
-                                                /* mask = 0 */
+/* 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, )
 
 static void mask_IO_APIC_irq (unsigned int irq)
 {
@@ -430,20 +451,6 @@ static int __init disable_timer_pin_setup(char *arg)
 }
 __setup("disable_timer_pin_1", disable_timer_pin_setup);
 
-static int __init setup_disable_8254_timer(char *s)
-{
-        timer_over_8254 = -1;
-        return 1;
-}
-static int __init setup_enable_8254_timer(char *s)
-{
-        timer_over_8254 = 2;
-        return 1;
-}
-
-__setup("disable_8254_timer", setup_disable_8254_timer);
-__setup("enable_8254_timer", setup_enable_8254_timer);
-
 
 /*
  * Find the IRQ entry number of a certain pin.
@@ -911,26 +918,21 @@ static void __init setup_IO_APIC_irqs(void)
 }
 
 /*
- * Set up the 8259A-master output pin as broadcast to all
- * CPUs.
+ * Set up the timer pin, possibly with the 8259A-master behind.
  */
-static void __init setup_ExtINT_IRQ0_pin(unsigned int apic, unsigned int pin, int vector)
+static void __init setup_timer_IRQ0_pin(unsigned int apic, unsigned int pin,
+                                        int vector)
 {
         struct IO_APIC_route_entry entry;
 
         memset(&entry, 0, sizeof(entry));
 
-        disable_8259A_irq(0);
-
-        /* mask LVT0 */
-        apic_write(APIC_LVT0, APIC_LVT_MASKED | APIC_DM_EXTINT);
-
         /*
          * We use logical delivery to get the timer IRQ
          * to the first CPU.
          */
         entry.dest_mode = INT_DEST_MODE;
-        entry.mask = 0;                                 /* unmask IRQ now */
+        entry.mask = 1;                                 /* mask IRQ now */
         entry.dest = cpu_mask_to_apicid(TARGET_CPUS);
         entry.delivery_mode = INT_DELIVERY_MODE;
         entry.polarity = 0;
@@ -939,7 +941,7 @@ static void __init setup_ExtINT_IRQ0_pin(unsigned int apic, unsigned int pin, in
 
         /*
          * The timer IRQ doesn't have to know that behind the
-         * scene we have a 8259A-master in AEOI mode ...
+         * scene we may have a 8259A-master in AEOI mode ...
          */
         set_irq_chip_and_handler_name(0, &ioapic_chip, handle_edge_irq, "edge");
 
@@ -947,8 +949,6 @@ static void __init setup_ExtINT_IRQ0_pin(unsigned int apic, unsigned int pin, in
          * Add it to the IO-APIC irq-routing table:
          */
         ioapic_write_entry(apic, pin, entry);
-
-        enable_8259A_irq(0);
 }
 
 void __apicdebuginit print_IO_APIC(void)
@@ -1660,6 +1660,7 @@ static inline void __init check_timer(void)
         struct irq_cfg *cfg = irq_cfg + 0;
         int apic1, pin1, apic2, pin2;
         unsigned long flags;
+        int no_pin1 = 0;
 
         local_irq_save(flags);
 
@@ -1670,16 +1671,11 @@ static inline void __init check_timer(void)
         assign_irq_vector(0, TARGET_CPUS);
 
         /*
-         * Subtle, code in do_timer_interrupt() expects an AEOI
-         * mode for the 8259A whenever interrupts are routed
-         * through I/O APICs.  Also IRQ0 has to be enabled in
-         * the 8259A which implies the virtual wire has to be
-         * disabled in the local APIC.
+         * As IRQ0 is to be enabled in the 8259A, the virtual
+         * wire has to be disabled in the local APIC.
          */
         apic_write(APIC_LVT0, APIC_LVT_MASKED | APIC_DM_EXTINT);
         init_8259A(1);
-        if (timer_over_8254 > 0)
-                enable_8259A_irq(0);
 
         pin1  = find_isa_irq_pin(0, mp_INT);
         apic1 = find_isa_irq_apic(0, mp_INT);
@@ -1689,15 +1685,39 @@ static inline void __init check_timer(void)
         apic_printk(APIC_VERBOSE,KERN_INFO "..TIMER: vector=0x%02X apic1=%d pin1=%d apic2=%d pin2=%d\n",
                 cfg->vector, apic1, pin1, apic2, pin2);
 
+        /*
+         * Some BIOS writers are clueless and report the ExtINTA
+         * I/O APIC input from the cascaded 8259A as the timer
+         * interrupt input.  So just in case, if only one pin
+         * was found above, try it both directly and through the
+         * 8259A.
+         */
+        if (pin1 == -1) {
+                pin1 = pin2;
+                apic1 = apic2;
+                no_pin1 = 1;
+        } else if (pin2 == -1) {
+                pin2 = pin1;
+                apic2 = apic1;
+        }
+
+        replace_pin_at_irq(0, 0, 0, apic1, pin1);
+        apic1 = 0;
+        pin1 = 0;
+        setup_timer_IRQ0_pin(apic1, pin1, cfg->vector);
+
         if (pin1 != -1) {
                 /*
                  * Ok, does IRQ0 through the IOAPIC work?
                  */
+                if (no_pin1) {
+                        add_pin_to_irq(0, apic1, pin1);
+                        setup_timer_IRQ0_pin(apic1, pin1, cfg->vector);
+                }
                 unmask_IO_APIC_irq(0);
                 if (!no_timer_check && timer_irq_works()) {
                         nmi_watchdog_default();
                         if (nmi_watchdog == NMI_IO_APIC) {
-                                disable_8259A_irq(0);
                                 setup_nmi();
                                 enable_8259A_irq(0);
                         }
@@ -1706,42 +1726,48 @@ static inline void __init check_timer(void)
                         goto out;
                 }
                 clear_IO_APIC_pin(apic1, pin1);
-                apic_printk(APIC_QUIET,KERN_ERR "..MP-BIOS bug: 8254 timer not "
-                                "connected to IO-APIC\n");
-        }
+                if (!no_pin1)
+                        apic_printk(APIC_QUIET,KERN_ERR "..MP-BIOS bug: "
+                                    "8254 timer not connected to IO-APIC\n");
 
-        apic_printk(APIC_VERBOSE,KERN_INFO "...trying to set up timer (IRQ0) "
-                                "through the 8259A ... ");
-        if (pin2 != -1) {
+                apic_printk(APIC_VERBOSE,KERN_INFO
+                        "...trying to set up timer (IRQ0) "
+                        "through the 8259A ... ");
                 apic_printk(APIC_VERBOSE,"\n..... (found apic %d pin %d) ...",
                         apic2, pin2);
                 /*
                  * legacy devices should be connected to IO APIC #0
                  */
-                setup_ExtINT_IRQ0_pin(apic2, pin2, cfg->vector);
+                replace_pin_at_irq(0, apic1, pin1, apic2, pin2);
+                setup_timer_IRQ0_pin(apic2, pin2, cfg->vector);
+                unmask_IO_APIC_irq(0);
+                enable_8259A_irq(0);
                 if (timer_irq_works()) {
                         apic_printk(APIC_VERBOSE," works.\n");
+                        timer_through_8259 = 1;
                         nmi_watchdog_default();
                         if (nmi_watchdog == NMI_IO_APIC) {
+                                disable_8259A_irq(0);
                                 setup_nmi();
+                                enable_8259A_irq(0);
                         }
                         goto out;
                 }
                 /*
                  * Cleanup, just in case ...
                  */
+                disable_8259A_irq(0);
                 clear_IO_APIC_pin(apic2, pin2);
+                apic_printk(APIC_VERBOSE," failed.\n");
         }
-        apic_printk(APIC_VERBOSE," 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;
+                nmi_watchdog = NMI_NONE;
         }
 
         apic_printk(APIC_VERBOSE, KERN_INFO "...trying to set up timer as Virtual Wire IRQ...");
 
-        disable_8259A_irq(0);
         irq_desc[0].chip = &lapic_irq_type;
         apic_write(APIC_LVT0, APIC_DM_FIXED | cfg->vector);     /* Fixed mode */
         enable_8259A_irq(0);
@@ -1750,6 +1776,7 @@ static inline void __init check_timer(void)
                 apic_printk(APIC_VERBOSE," works.\n");
                 goto out;
         }
+        disable_8259A_irq(0);
         apic_write(APIC_LVT0, APIC_LVT_MASKED | APIC_DM_FIXED | cfg->vector);
         apic_printk(APIC_VERBOSE," failed.\n");