x86: apic - unify setup_local_APIC

- remove useless read of APIC_LVR
- wrap with preempt_disable/enable
- check for integrated APIC just in place

v2: fix by Yinghai Lu.
	fix lapic_is_integrated using
	let 64-bit too have pic_mode

Signed-off-by: Cyrill Gorcunov <gorcunov@gmail.com>
Signed-off-by: Yinghai Lu <yhlu.kernel@gmail.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
diff --git a/arch/x86/kernel/apic_64.c b/arch/x86/kernel/apic_64.c
index 4587e16..283968d 100644
--- a/arch/x86/kernel/apic_64.c
+++ b/arch/x86/kernel/apic_64.c
@@ -76,6 +76,8 @@
  */
 unsigned int apic_verbosity;
 
+int pic_mode;
+
 /* Have we found an MP table */
 int smp_found_config;
 
@@ -943,8 +945,17 @@
 	unsigned int value;
 	int i, j;
 
+#ifdef CONFIG_X86_32
+	/* Pound the ESR really hard over the head with a big hammer - mbligh */
+	if (esr_disable) {
+		apic_write(APIC_ESR, 0);
+		apic_write(APIC_ESR, 0);
+		apic_write(APIC_ESR, 0);
+		apic_write(APIC_ESR, 0);
+	}
+#endif
+
 	preempt_disable();
-	value = apic_read(APIC_LVR);
 
 	/*
 	 * Double-check whether this APIC is really registered.
@@ -997,7 +1008,34 @@
 	 */
 	value |= APIC_SPIV_APIC_ENABLED;
 
-	/* We always use processor focus */
+#ifdef CONFIG_X86_32
+	/*
+	 * Some unknown Intel IO/APIC (or APIC) errata is biting us with
+	 * certain networking cards. If high frequency interrupts are
+	 * happening on a particular IOAPIC pin, plus the IOAPIC routing
+	 * entry is masked/unmasked at a high rate as well then sooner or
+	 * later IOAPIC line gets 'stuck', no more interrupts are received
+	 * from the device. If focus CPU is disabled then the hang goes
+	 * away, oh well :-(
+	 *
+	 * [ This bug can be reproduced easily with a level-triggered
+	 *   PCI Ne2000 networking cards and PII/PIII processors, dual
+	 *   BX chipset. ]
+	 */
+	/*
+	 * Actually disabling the focus CPU check just makes the hang less
+	 * frequent as it makes the interrupt distributon model be more
+	 * like LRU than MRU (the short-term load is more even across CPUs).
+	 * See also the comment in end_level_ioapic_irq().  --macro
+	 */
+
+	/*
+	 * - enable focus processor (bit==0)
+	 * - 64bit mode always use processor focus
+	 *   so no need to set it
+	 */
+	value &= ~APIC_SPIV_FOCUS_DISABLED;
+#endif
 
 	/*
 	 * Set spurious IRQ vector
@@ -1016,14 +1054,14 @@
 	 * TODO: set up through-local-APIC from through-I/O-APIC? --macro
 	 */
 	value = apic_read(APIC_LVT0) & APIC_LVT_MASKED;
-	if (!smp_processor_id() && !value) {
+	if (!smp_processor_id() && (pic_mode || !value)) {
 		value = APIC_DM_EXTINT;
 		apic_printk(APIC_VERBOSE, "enabled ExtINT on CPU#%d\n",
-			    smp_processor_id());
+				smp_processor_id());
 	} else {
 		value = APIC_DM_EXTINT | APIC_LVT_MASKED;
 		apic_printk(APIC_VERBOSE, "masked ExtINT on CPU#%d\n",
-			    smp_processor_id());
+				smp_processor_id());
 	}
 	apic_write(APIC_LVT0, value);
 
@@ -1034,7 +1072,10 @@
 		value = APIC_DM_NMI;
 	else
 		value = APIC_DM_NMI | APIC_LVT_MASKED;
+	if (!lapic_is_integrated())		/* 82489DX */
+		value |= APIC_LVT_LEVEL_TRIGGER;
 	apic_write(APIC_LVT1, value);
+
 	preempt_enable();
 }