--- /dev/null
+/*
+ * Local APIC handling, local APIC timers
+ *
+ * (c) 1999, 2000 Ingo Molnar <mingo@redhat.com>
+ *
+ * Fixes
+ * Maciej W. Rozycki : Bits for genuine 82489DX APICs;
+ * thanks to Eric Gilmore
+ * and Rolf G. Tews
+ * for testing these extensively.
+ * Maciej W. Rozycki : Various updates and fixes.
+ * Mikael Pettersson : Power Management for UP-APIC.
+ * Pavel Machek and
+ * Mikael Pettersson : PM converted to driver model.
+ */
+
+#include <linux/config.h>
+#include <linux/init.h>
+
+#include <linux/mm.h>
+#include <linux/delay.h>
+#include <linux/bootmem.h>
+#include <linux/smp_lock.h>
+#include <linux/interrupt.h>
+#include <linux/mc146818rtc.h>
+#include <linux/kernel_stat.h>
+#include <linux/sysdev.h>
+#include <linux/module.h>
+
+#include <asm/atomic.h>
+#include <asm/smp.h>
+#include <asm/mtrr.h>
+#include <asm/mpspec.h>
+#include <asm/desc.h>
+#include <asm/arch_hooks.h>
+#include <asm/hpet.h>
+#include <asm/idle.h>
+
+int apic_verbosity;
+
+/*
+ * 'what should we do if we get a hw irq event on an illegal vector'.
+ * each architecture has to answer this themselves.
+ */
+void ack_bad_irq(unsigned int irq)
+{
+ printk("unexpected IRQ trap at vector %02x\n", irq);
+ /*
+ * Currently unexpected vectors happen only on SMP and APIC.
+ * We _must_ ack these because every local APIC has only N
+ * irq slots per priority level, and a 'hanging, unacked' IRQ
+ * holds up an irq slot - in excessive cases (when multiple
+ * unexpected vectors occur) that might lock up the APIC
+ * completely.
+ * But don't ack when the APIC is disabled. -AK
+ */
+ if (!disable_apic)
+ ack_APIC_irq();
+}
+
+int setup_profiling_timer(unsigned int multiplier)
+{
+ return -EINVAL;
+}
+
+void smp_local_timer_interrupt(struct pt_regs *regs)
+{
+ profile_tick(CPU_PROFILING, regs);
+#ifndef CONFIG_XEN
+#ifdef CONFIG_SMP
+ update_process_times(user_mode(regs));
+#endif
+#endif
+ /*
+ * We take the 'long' return path, and there every subsystem
+ * grabs the appropriate locks (kernel lock/ irq lock).
+ *
+ * we might want to decouple profiling from the 'long path',
+ * and do the profiling totally in assembly.
+ *
+ * Currently this isn't too much of an issue (performance wise),
+ * we can take more than 100K local irqs per second on a 100 MHz P5.
+ */
+}
+
+/*
+ * Local APIC timer interrupt. This is the most natural way for doing
+ * local interrupts, but local timer interrupts can be emulated by
+ * broadcast interrupts too. [in case the hw doesn't support APIC timers]
+ *
+ * [ if a single-CPU system runs an SMP kernel then we call the local
+ * interrupt as well. Thus we cannot inline the local irq ... ]
+ */
+void smp_apic_timer_interrupt(struct pt_regs *regs)
+{
+ /*
+ * the NMI deadlock-detector uses this.
+ */
+ add_pda(apic_timer_irqs, 1);
+
+ /*
+ * NOTE! We'd better ACK the irq immediately,
+ * because timer handling can be slow.
+ */
+ ack_APIC_irq();
+ /*
+ * update_process_times() expects us to have done irq_enter().
+ * Besides, if we don't timer interrupts ignore the global
+ * interrupt lock, which is the WrongThing (tm) to do.
+ */
+ exit_idle();
+ irq_enter();
+ smp_local_timer_interrupt(regs);
+ irq_exit();
+}
+
+/*
+ * This interrupt should _never_ happen with our APIC/SMP architecture
+ */
+asmlinkage void smp_spurious_interrupt(void)
+{
+ unsigned int v;
+ exit_idle();
+ irq_enter();
+ /*
+ * Check if this really is a spurious interrupt and ACK it
+ * if it is a vectored one. Just in case...
+ * Spurious interrupts should not be ACKed.
+ */
+ v = apic_read(APIC_ISR + ((SPURIOUS_APIC_VECTOR & ~0x1f) >> 1));
+ if (v & (1 << (SPURIOUS_APIC_VECTOR & 0x1f)))
+ ack_APIC_irq();
+
+#if 0
+ static unsigned long last_warning;
+ static unsigned long skipped;
+
+ /* see sw-dev-man vol 3, chapter 7.4.13.5 */
+ if (time_before(last_warning+30*HZ,jiffies)) {
+ printk(KERN_INFO "spurious APIC interrupt on CPU#%d, %ld skipped.\n",
+ smp_processor_id(), skipped);
+ last_warning = jiffies;
+ skipped = 0;
+ } else {
+ skipped++;
+ }
+#endif
+ irq_exit();
+}
+
+/*
+ * This interrupt should never happen with our APIC/SMP architecture
+ */
+
+asmlinkage void smp_error_interrupt(void)
+{
+ unsigned int v, v1;
+
+ exit_idle();
+ irq_enter();
+ /* First tickle the hardware, only then report what went on. -- REW */
+ v = apic_read(APIC_ESR);
+ apic_write(APIC_ESR, 0);
+ v1 = apic_read(APIC_ESR);
+ ack_APIC_irq();
+ atomic_inc(&irq_err_count);
+
+ /* Here is what the APIC error bits mean:
+ 0: Send CS error
+ 1: Receive CS error
+ 2: Send accept error
+ 3: Receive accept error
+ 4: Reserved
+ 5: Send illegal vector
+ 6: Received illegal vector
+ 7: Illegal register address
+ */
+ printk (KERN_DEBUG "APIC error on CPU%d: %02x(%02x)\n",
+ smp_processor_id(), v , v1);
+ irq_exit();
+}
+
+int disable_apic;
+
+/*
+ * This initializes the IO-APIC and APIC hardware if this is
+ * a UP kernel.
+ */
+int __init APIC_init_uniprocessor (void)
+{
+#ifdef CONFIG_X86_IO_APIC
+ if (smp_found_config)
+ if (!skip_ioapic_setup && nr_ioapics)
+ setup_IO_APIC();
+#endif
+
+ return 1;
+}
git://git.onelab.eu / linux-2.6.git / blobdiff