From: Thomas Gleixner <[email protected]>
The apic code is quite unstructured and missing a lot of comments.
- Restructure the code into helper functions, timer, setup/shutdown,
interrupt and power management blocks.
- Fixup comments.
- Namespace fixups
- Inline helpers for version and is_integrated
- Combine the ack_bad_irq functions
No functional changes.
Signed-off-by: Thomas Gleixner <[email protected]>
Signed-off-by: Ingo Molnar <[email protected]>
Index: linux-2.6.19-rc5-mm1/arch/i386/kernel/apic.c
===================================================================
--- linux-2.6.19-rc5-mm1.orig/arch/i386/kernel/apic.c 2006-11-09 21:05:30.000000000 +0100
+++ linux-2.6.19-rc5-mm1/arch/i386/kernel/apic.c 2006-11-09 21:06:15.000000000 +0100
@@ -44,6 +44,13 @@
#include "io_ports.h"
/*
+ * Sanity check
+ */
+#if (SPURIOUS_APIC_VECTOR & 0x0F) != 0x0F
+# error SPURIOUS_APIC_VECTOR definition error
+#endif
+
+/*
* cpu_mask that denotes the CPUs that needs timer interrupt coming in as
* IPIs in place of local APIC timers
*/
@@ -51,561 +58,559 @@ static cpumask_t timer_bcast_ipi;
/*
* Knob to control our willingness to enable the local APIC.
+ *
+ * -1=force-disable, +1=force-enable
*/
-static int enable_local_apic __initdata = 0; /* -1=force-disable, +1=force-enable */
-
-static inline void lapic_disable(void)
-{
- enable_local_apic = -1;
- clear_bit(X86_FEATURE_APIC, boot_cpu_data.x86_capability);
-}
-
-static inline void lapic_enable(void)
-{
- enable_local_apic = 1;
-}
+static int enable_local_apic __initdata = 0;
/*
- * Debug level
+ * Debug level, exported for io_apic.c
*/
int apic_verbosity;
-
static void apic_pm_activate(void);
-static int modern_apic(void)
+
+/* Using APIC to generate smp_local_timer_interrupt? */
+int using_apic_timer __read_mostly = 0;
+
+/* Local APIC was disabled by the BIOS and enabled by the kernel */
+static int enabled_via_apicbase;
+
+/*
+ * Get the LAPIC version
+ */
+static inline int lapic_get_version(void)
{
- unsigned int lvr, version;
- /* AMD systems use old APIC versions, so check the CPU */
- if (boot_cpu_data.x86_vendor == X86_VENDOR_AMD &&
- boot_cpu_data.x86 >= 0xf)
- return 1;
- lvr = apic_read(APIC_LVR);
- version = GET_APIC_VERSION(lvr);
- return version >= 0x14;
+ return GET_APIC_VERSION(apic_read(APIC_LVR));
}
/*
- * 'what should we do if we get a hw irq event on an illegal vector'.
- * each architecture has to answer this themselves.
+ * Check, if the APIC is integrated or a seperate chip
*/
-void ack_bad_irq(unsigned int irq)
+static inline int lapic_is_integrated(void)
{
- 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 only ack when the APIC is enabled -AK
- */
- if (cpu_has_apic)
- ack_APIC_irq();
+ return APIC_INTEGRATED(lapic_get_version());
}
-void __init apic_intr_init(void)
+/*
+ * Check, whether this is a modern or a first generation APIC
+ */
+static int modern_apic(void)
{
-#ifdef CONFIG_SMP
- smp_intr_init();
-#endif
- /* self generated IPI for local APIC timer */
- set_intr_gate(LOCAL_TIMER_VECTOR, apic_timer_interrupt);
-
- /* IPI vectors for APIC spurious and error interrupts */
- set_intr_gate(SPURIOUS_APIC_VECTOR, spurious_interrupt);
- set_intr_gate(ERROR_APIC_VECTOR, error_interrupt);
-
- /* thermal monitor LVT interrupt */
-#ifdef CONFIG_X86_MCE_P4THERMAL
- set_intr_gate(THERMAL_APIC_VECTOR, thermal_interrupt);
-#endif
+ /* AMD systems use old APIC versions, so check the CPU */
+ if (boot_cpu_data.x86_vendor == X86_VENDOR_AMD &&
+ boot_cpu_data.x86 >= 0xf)
+ return 1;
+ return lapic_get_version() >= 0x14;
}
-/* Using APIC to generate smp_local_timer_interrupt? */
-int using_apic_timer __read_mostly = 0;
-
-static int enabled_via_apicbase;
-
+/**
+ * enable_NMI_through_LVT0 - enable NMI through local vector table 0
+ */
void enable_NMI_through_LVT0 (void * dummy)
{
- unsigned int v, ver;
+ unsigned int v = APIC_DM_NMI;
- ver = apic_read(APIC_LVR);
- ver = GET_APIC_VERSION(ver);
- v = APIC_DM_NMI; /* unmask and set to NMI */
- if (!APIC_INTEGRATED(ver)) /* 82489DX */
+ /* Level triggered for 82489DX */
+ if (!lapic_is_integrated())
v |= APIC_LVT_LEVEL_TRIGGER;
apic_write_around(APIC_LVT0, v);
}
+/**
+ * get_physical_broadcast - Get number of physical broadcast IDs
+ */
int get_physical_broadcast(void)
{
- if (modern_apic())
- return 0xff;
- else
- return 0xf;
+ return modern_apic() ? 0xff : 0xf;
}
-int get_maxlvt(void)
+/**
+ * lapic_get_maxlvt - get the maximum number of local vector table entries
+ */
+int lapic_get_maxlvt(void)
{
- unsigned int v, ver, maxlvt;
+ unsigned int v = apic_read(APIC_LVR);
- v = apic_read(APIC_LVR);
- ver = GET_APIC_VERSION(v);
/* 82489DXs do not report # of LVT entries. */
- maxlvt = APIC_INTEGRATED(ver) ? GET_APIC_MAXLVT(v) : 2;
- return maxlvt;
+ return APIC_INTEGRATED(GET_APIC_VERSION(v)) ? GET_APIC_MAXLVT(v) : 2;
}
-void clear_local_APIC(void)
+/*
+ * Local APIC timer
+ */
+
+/*
+ * This part sets up the APIC 32 bit clock in LVTT1, with HZ interrupts
+ * per second. We assume that the caller has already set up the local
+ * APIC.
+ *
+ * The APIC timer is not exactly sync with the external timer chip, it
+ * closely follows bus clocks.
+ */
+
+/*
+ * The timer chip is already set up at HZ interrupts per second here,
+ * but we do not accept timer interrupts yet. We only allow the BP
+ * to calibrate.
+ */
+static unsigned int __devinit get_8254_timer_count(void)
{
- int maxlvt;
- unsigned long v;
+ unsigned long flags;
- maxlvt = get_maxlvt();
+ unsigned int count;
- /*
- * Masking an LVT entry can trigger a local APIC error
- * if the vector is zero. Mask LVTERR first to prevent this.
- */
- if (maxlvt >= 3) {
- v = ERROR_APIC_VECTOR; /* any non-zero vector will do */
- apic_write_around(APIC_LVTERR, v | APIC_LVT_MASKED);
- }
- /*
- * Careful: we have to set masks only first to deassert
- * any level-triggered sources.
- */
- v = apic_read(APIC_LVTT);
- apic_write_around(APIC_LVTT, v | APIC_LVT_MASKED);
- v = apic_read(APIC_LVT0);
- apic_write_around(APIC_LVT0, v | APIC_LVT_MASKED);
- v = apic_read(APIC_LVT1);
- apic_write_around(APIC_LVT1, v | APIC_LVT_MASKED);
- if (maxlvt >= 4) {
- v = apic_read(APIC_LVTPC);
- apic_write_around(APIC_LVTPC, v | APIC_LVT_MASKED);
- }
+ spin_lock_irqsave(&i8253_lock, flags);
-/* lets not touch this if we didn't frob it */
-#ifdef CONFIG_X86_MCE_P4THERMAL
- if (maxlvt >= 5) {
- v = apic_read(APIC_LVTTHMR);
- apic_write_around(APIC_LVTTHMR, v | APIC_LVT_MASKED);
- }
-#endif
- /*
- * Clean APIC state for other OSs:
- */
- apic_write_around(APIC_LVTT, APIC_LVT_MASKED);
- apic_write_around(APIC_LVT0, APIC_LVT_MASKED);
- apic_write_around(APIC_LVT1, APIC_LVT_MASKED);
- if (maxlvt >= 3)
- apic_write_around(APIC_LVTERR, APIC_LVT_MASKED);
- if (maxlvt >= 4)
- apic_write_around(APIC_LVTPC, APIC_LVT_MASKED);
+ outb_p(0x00, PIT_MODE);
+ count = inb_p(PIT_CH0);
+ count |= inb_p(PIT_CH0) << 8;
-#ifdef CONFIG_X86_MCE_P4THERMAL
- if (maxlvt >= 5)
- apic_write_around(APIC_LVTTHMR, APIC_LVT_MASKED);
-#endif
- v = GET_APIC_VERSION(apic_read(APIC_LVR));
- if (APIC_INTEGRATED(v)) { /* !82489DX */
- if (maxlvt > 3) /* Due to Pentium errata 3AP and 11AP. */
- apic_write(APIC_ESR, 0);
- apic_read(APIC_ESR);
- }
-}
+ spin_unlock_irqrestore(&i8253_lock, flags);
-void __init connect_bsp_APIC(void)
-{
- if (pic_mode) {
- /*
- * Do not trust the local APIC being empty at bootup.
- */
- clear_local_APIC();
- /*
- * PIC mode, enable APIC mode in the IMCR, i.e.
- * connect BSP's local APIC to INT and NMI lines.
- */
- apic_printk(APIC_VERBOSE, "leaving PIC mode, "
- "enabling APIC mode.\n");
- outb(0x70, 0x22);
- outb(0x01, 0x23);
- }
- enable_apic_mode();
+ return count;
}
-void disconnect_bsp_APIC(int virt_wire_setup)
+/* next tick in 8254 can be caught by catching timer wraparound */
+static void __devinit wait_8254_wraparound(void)
{
- if (pic_mode) {
- /*
- * Put the board back into PIC mode (has an effect
- * only on certain older boards). Note that APIC
- * interrupts, including IPIs, won't work beyond
- * this point! The only exception are INIT IPIs.
- */
- apic_printk(APIC_VERBOSE, "disabling APIC mode, "
- "entering PIC mode.\n");
- outb(0x70, 0x22);
- outb(0x00, 0x23);
- }
- else {
- /* Go back to Virtual Wire compatibility mode */
- unsigned long value;
+ unsigned int curr_count, prev_count;
- /* For the spurious interrupt use vector F, and enable it */
- value = apic_read(APIC_SPIV);
- value &= ~APIC_VECTOR_MASK;
- value |= APIC_SPIV_APIC_ENABLED;
- value |= 0xf;
- apic_write_around(APIC_SPIV, value);
+ curr_count = get_8254_timer_count();
+ do {
+ prev_count = curr_count;
+ curr_count = get_8254_timer_count();
- if (!virt_wire_setup) {
- /* For LVT0 make it edge triggered, active high, external and enabled */
- value = apic_read(APIC_LVT0);
- value &= ~(APIC_MODE_MASK | APIC_SEND_PENDING |
- APIC_INPUT_POLARITY | APIC_LVT_REMOTE_IRR |
- APIC_LVT_LEVEL_TRIGGER | APIC_LVT_MASKED );
- value |= APIC_LVT_REMOTE_IRR | APIC_SEND_PENDING;
- value = SET_APIC_DELIVERY_MODE(value, APIC_MODE_EXTINT);
- apic_write_around(APIC_LVT0, value);
- }
- else {
- /* Disable LVT0 */
- apic_write_around(APIC_LVT0, APIC_LVT_MASKED);
- }
+ /* workaround for broken Mercury/Neptune */
+ if (prev_count >= curr_count + 0x100)
+ curr_count = get_8254_timer_count();
- /* For LVT1 make it edge triggered, active high, nmi and enabled */
- value = apic_read(APIC_LVT1);
- value &= ~(
- APIC_MODE_MASK | APIC_SEND_PENDING |
- APIC_INPUT_POLARITY | APIC_LVT_REMOTE_IRR |
- APIC_LVT_LEVEL_TRIGGER | APIC_LVT_MASKED);
- value |= APIC_LVT_REMOTE_IRR | APIC_SEND_PENDING;
- value = SET_APIC_DELIVERY_MODE(value, APIC_MODE_NMI);
- apic_write_around(APIC_LVT1, value);
- }
+ } while (prev_count >= curr_count);
}
-void disable_local_APIC(void)
+/*
+ * Default initialization for 8254 timers. If we use other timers like HPET,
+ * we override this later
+ */
+void (*wait_timer_tick)(void) __devinitdata = wait_8254_wraparound;
+
+/*
+ * This function sets up the local APIC timer, with a timeout of
+ * 'clocks' APIC bus clock. During calibration we actually call
+ * this function twice on the boot CPU, once with a bogus timeout
+ * value, second time for real. The other (noncalibrating) CPUs
+ * call this function only once, with the real, calibrated value.
+ *
+ * We do reads before writes even if unnecessary, to get around the
+ * P5 APIC double write bug.
+ */
+
+#define APIC_DIVISOR 16
+
+static void __setup_APIC_LVTT(unsigned int clocks)
{
- unsigned long value;
+ unsigned int lvtt_value, tmp_value;
+ int cpu = smp_processor_id();
- clear_local_APIC();
+ lvtt_value = APIC_LVT_TIMER_PERIODIC | LOCAL_TIMER_VECTOR;
+ if (!lapic_is_integrated())
+ lvtt_value |= SET_APIC_TIMER_BASE(APIC_TIMER_BASE_DIV);
+
+ if (cpu_isset(cpu, timer_bcast_ipi))
+ lvtt_value |= APIC_LVT_MASKED;
+
+ apic_write_around(APIC_LVTT, lvtt_value);
/*
- * Disable APIC (implies clearing of registers
- * for 82489DX!).
+ * Divide PICLK by 16
*/
- value = apic_read(APIC_SPIV);
- value &= ~APIC_SPIV_APIC_ENABLED;
- apic_write_around(APIC_SPIV, value);
+ tmp_value = apic_read(APIC_TDCR);
+ apic_write_around(APIC_TDCR, (tmp_value
+ & ~(APIC_TDR_DIV_1 | APIC_TDR_DIV_TMBASE))
+ | APIC_TDR_DIV_16);
- if (enabled_via_apicbase) {
- unsigned int l, h;
- rdmsr(MSR_IA32_APICBASE, l, h);
- l &= ~MSR_IA32_APICBASE_ENABLE;
- wrmsr(MSR_IA32_APICBASE, l, h);
- }
+ apic_write_around(APIC_TMICT, clocks/APIC_DIVISOR);
}
-/*
- * This is to verify that we're looking at a real local APIC.
- * Check these against your board if the CPUs aren't getting
- * started for no apparent reason.
- */
-int __init verify_local_APIC(void)
+static void __devinit setup_APIC_timer(unsigned int clocks)
{
- unsigned int reg0, reg1;
+ unsigned long flags;
+
+ local_irq_save(flags);
/*
- * The version register is read-only in a real APIC.
+ * Wait for IRQ0's slice:
*/
- reg0 = apic_read(APIC_LVR);
- apic_printk(APIC_DEBUG, "Getting VERSION: %x\n", reg0);
- apic_write(APIC_LVR, reg0 ^ APIC_LVR_MASK);
- reg1 = apic_read(APIC_LVR);
- apic_printk(APIC_DEBUG, "Getting VERSION: %x\n", reg1);
+ wait_timer_tick();
+
+ __setup_APIC_LVTT(clocks);
+
+ local_irq_restore(flags);
+}
+
+/*
+ * In this function we calibrate APIC bus clocks to the external
+ * timer. Unfortunately we cannot use jiffies and the timer irq
+ * to calibrate, since some later bootup code depends on getting
+ * the first irq? Ugh.
+ *
+ * We want to do the calibration only once since we
+ * want to have local timer irqs syncron. CPUs connected
+ * by the same APIC bus have the very same bus frequency.
+ * And we want to have irqs off anyways, no accidental
+ * APIC irq that way.
+ */
+
+static int __init calibrate_APIC_clock(void)
+{
+ unsigned long long t1 = 0, t2 = 0;
+ long tt1, tt2;
+ long result;
+ int i;
+ const int LOOPS = HZ/10;
+
+ apic_printk(APIC_VERBOSE, "calibrating APIC timer ...\n");
/*
- * The two version reads above should print the same
- * numbers. If the second one is different, then we
- * poke at a non-APIC.
+ * Put whatever arbitrary (but long enough) timeout
+ * value into the APIC clock, we just want to get the
+ * counter running for calibration.
*/
- if (reg1 != reg0)
- return 0;
+ __setup_APIC_LVTT(1000000000);
/*
- * Check if the version looks reasonably.
+ * The timer chip counts down to zero. Let's wait
+ * for a wraparound to start exact measurement:
+ * (the current tick might have been already half done)
*/
- reg1 = GET_APIC_VERSION(reg0);
- if (reg1 == 0x00 || reg1 == 0xff)
- return 0;
- reg1 = get_maxlvt();
- if (reg1 < 0x02 || reg1 == 0xff)
- return 0;
+
+ wait_timer_tick();
/*
- * The ID register is read/write in a real APIC.
+ * We wrapped around just now. Let's start:
*/
- reg0 = apic_read(APIC_ID);
- apic_printk(APIC_DEBUG, "Getting ID: %x\n", reg0);
+ if (cpu_has_tsc)
+ rdtscll(t1);
+ tt1 = apic_read(APIC_TMCCT);
/*
- * The next two are just to see if we have sane values.
- * They're only really relevant if we're in Virtual Wire
- * compatibility mode, but most boxes are anymore.
+ * Let's wait LOOPS wraprounds:
*/
- reg0 = apic_read(APIC_LVT0);
- apic_printk(APIC_DEBUG, "Getting LVT0: %x\n", reg0);
- reg1 = apic_read(APIC_LVT1);
- apic_printk(APIC_DEBUG, "Getting LVT1: %x\n", reg1);
+ for (i = 0; i < LOOPS; i++)
+ wait_timer_tick();
- return 1;
-}
+ tt2 = apic_read(APIC_TMCCT);
+ if (cpu_has_tsc)
+ rdtscll(t2);
-void __init sync_Arb_IDs(void)
-{
- /* Unsupported on P4 - see Intel Dev. Manual Vol. 3, Ch. 8.6.1
- And not needed on AMD */
- if (modern_apic())
- return;
/*
- * Wait for idle.
+ * The APIC bus clock counter is 32 bits only, it
+ * might have overflown, but note that we use signed
+ * longs, thus no extra care needed.
+ *
+ * underflown to be exact, as the timer counts down ;)
*/
- apic_wait_icr_idle();
- apic_printk(APIC_DEBUG, "Synchronizing Arb IDs.\n");
- apic_write_around(APIC_ICR, APIC_DEST_ALLINC | APIC_INT_LEVELTRIG
- | APIC_DM_INIT);
+ result = (tt1-tt2)*APIC_DIVISOR/LOOPS;
+
+ if (cpu_has_tsc)
+ apic_printk(APIC_VERBOSE, "..... CPU clock speed is "
+ "%ld.%04ld MHz.\n",
+ ((long)(t2-t1)/LOOPS)/(1000000/HZ),
+ ((long)(t2-t1)/LOOPS)%(1000000/HZ));
+
+ apic_printk(APIC_VERBOSE, "..... host bus clock speed is "
+ "%ld.%04ld MHz.\n",
+ result/(1000000/HZ),
+ result%(1000000/HZ));
+
+ return result;
}
-extern void __error_in_apic_c (void);
+static unsigned int calibration_result;
-/*
- * An initial setup of the virtual wire mode.
- */
-void __init init_bsp_APIC(void)
+void __init setup_boot_APIC_clock(void)
{
- unsigned long value, ver;
+ unsigned long flags;
+ apic_printk(APIC_VERBOSE, "Using local APIC timer interrupts.\n");
+ using_apic_timer = 1;
+
+ local_irq_save(flags);
+ calibration_result = calibrate_APIC_clock();
/*
- * Don't do the setup now if we have a SMP BIOS as the
- * through-I/O-APIC virtual wire mode might be active.
+ * Now set up the timer for real.
*/
- if (smp_found_config || !cpu_has_apic)
- return;
+ setup_APIC_timer(calibration_result);
+
+ local_irq_restore(flags);
+}
- value = apic_read(APIC_LVR);
- ver = GET_APIC_VERSION(value);
+void __devinit setup_secondary_APIC_clock(void)
+{
+ setup_APIC_timer(calibration_result);
+}
- /*
- * Do not trust the local APIC being empty at bootup.
- */
- clear_local_APIC();
+void disable_APIC_timer(void)
+{
+ if (using_apic_timer) {
+ unsigned long v;
- /*
- * Enable APIC.
- */
- value = apic_read(APIC_SPIV);
- value &= ~APIC_VECTOR_MASK;
- value |= APIC_SPIV_APIC_ENABLED;
-
- /* This bit is reserved on P4/Xeon and should be cleared */
- if ((boot_cpu_data.x86_vendor == X86_VENDOR_INTEL) && (boot_cpu_data.x86 == 15))
- value &= ~APIC_SPIV_FOCUS_DISABLED;
- else
- value |= APIC_SPIV_FOCUS_DISABLED;
- value |= SPURIOUS_APIC_VECTOR;
- apic_write_around(APIC_SPIV, value);
+ v = apic_read(APIC_LVTT);
+ /*
+ * When an illegal vector value (0-15) is written to an LVT
+ * entry and delivery mode is Fixed, the APIC may signal an
+ * illegal vector error, with out regard to whether the mask
+ * bit is set or whether an interrupt is actually seen on
+ * input.
+ *
+ * Boot sequence might call this function when the LVTT has
+ * '0' vector value. So make sure vector field is set to
+ * valid value.
+ */
+ v |= (APIC_LVT_MASKED | LOCAL_TIMER_VECTOR);
+ apic_write_around(APIC_LVTT, v);
+ }
+}
- /*
- * Set up the virtual wire mode.
- */
- apic_write_around(APIC_LVT0, APIC_DM_EXTINT);
- value = APIC_DM_NMI;
- if (!APIC_INTEGRATED(ver)) /* 82489DX */
- value |= APIC_LVT_LEVEL_TRIGGER;
- apic_write_around(APIC_LVT1, value);
+void enable_APIC_timer(void)
+{
+ int cpu = smp_processor_id();
+
+ if (using_apic_timer && !cpu_isset(cpu, timer_bcast_ipi)) {
+ unsigned long v;
+
+ v = apic_read(APIC_LVTT);
+ apic_write_around(APIC_LVTT, v & ~APIC_LVT_MASKED);
+ }
}
-void __devinit setup_local_APIC(void)
+void switch_APIC_timer_to_ipi(void *cpumask)
{
- unsigned long oldvalue, value, ver, maxlvt;
- int i, j;
+ cpumask_t mask = *(cpumask_t *)cpumask;
+ int cpu = smp_processor_id();
- /* 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);
+ if (cpu_isset(cpu, mask) &&
+ !cpu_isset(cpu, timer_bcast_ipi)) {
+ disable_APIC_timer();
+ cpu_set(cpu, timer_bcast_ipi);
}
+}
+EXPORT_SYMBOL(switch_APIC_timer_to_ipi);
- value = apic_read(APIC_LVR);
- ver = GET_APIC_VERSION(value);
+void switch_ipi_to_APIC_timer(void *cpumask)
+{
+ cpumask_t mask = *(cpumask_t *)cpumask;
+ int cpu = smp_processor_id();
+
+ if (cpu_isset(cpu, mask) &&
+ cpu_isset(cpu, timer_bcast_ipi)) {
+ cpu_clear(cpu, timer_bcast_ipi);
+ enable_APIC_timer();
+ }
+}
+EXPORT_SYMBOL(switch_ipi_to_APIC_timer);
- if ((SPURIOUS_APIC_VECTOR & 0x0f) != 0x0f)
- __error_in_apic_c();
+/*
+ * Local timer interrupt handler. It does both profiling and
+ * process statistics/rescheduling.
+ */
+inline void smp_local_timer_interrupt(void)
+{
+ profile_tick(CPU_PROFILING);
+#ifdef CONFIG_SMP
+ update_process_times(user_mode_vm(get_irq_regs()));
+#endif
/*
- * Double-check whether this APIC is really registered.
+ * We take the 'long' return path, and there every subsystem
+ * grabs the apropriate 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.
*/
- if (!apic_id_registered())
- BUG();
+}
+
+/*
+ * 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 ... ]
+ */
+
+fastcall void smp_apic_timer_interrupt(struct pt_regs *regs)
+{
+ struct pt_regs *old_regs = set_irq_regs(regs);
+ int cpu = smp_processor_id();
/*
- * Intel recommends to set DFR, LDR and TPR before enabling
- * an APIC. See e.g. "AP-388 82489DX User's Manual" (Intel
- * document number 292116). So here it goes...
+ * the NMI deadlock-detector uses this.
*/
- init_apic_ldr();
+ per_cpu(irq_stat, cpu).apic_timer_irqs++;
/*
- * Set Task Priority to 'accept all'. We never change this
- * later on.
+ * NOTE! We'd better ACK the irq immediately,
+ * because timer handling can be slow.
*/
- value = apic_read(APIC_TASKPRI);
- value &= ~APIC_TPRI_MASK;
- apic_write_around(APIC_TASKPRI, value);
-
+ ack_APIC_irq();
/*
- * After a crash, we no longer service the interrupts and a pending
- * interrupt from previous kernel might still have ISR bit set.
- *
- * Most probably by now CPU has serviced that pending interrupt and
- * it might not have done the ack_APIC_irq() because it thought,
- * interrupt came from i8259 as ExtInt. LAPIC did not get EOI so it
- * does not clear the ISR bit and cpu thinks it has already serivced
- * the interrupt. Hence a vector might get locked. It was noticed
- * for timer irq (vector 0x31). Issue an extra EOI to clear ISR.
+ * 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.
*/
- for (i = APIC_ISR_NR - 1; i >= 0; i--) {
- value = apic_read(APIC_ISR + i*0x10);
- for (j = 31; j >= 0; j--) {
- if (value & (1<<j))
- ack_APIC_irq();
- }
- }
+ irq_enter();
+ smp_local_timer_interrupt();
+ irq_exit();
+ set_irq_regs(old_regs);
+}
- /*
- * Now that we are all set up, enable the APIC
- */
- value = apic_read(APIC_SPIV);
- value &= ~APIC_VECTOR_MASK;
- /*
- * Enable APIC
- */
- value |= APIC_SPIV_APIC_ENABLED;
+#ifndef CONFIG_SMP
+static void up_apic_timer_interrupt_call(void)
+{
+ int cpu = smp_processor_id();
/*
- * 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
+ * the NMI deadlock-detector uses this.
*/
-#if 1
- /* Enable focus processor (bit==0) */
- value &= ~APIC_SPIV_FOCUS_DISABLED;
+ per_cpu(irq_stat, cpu).apic_timer_irqs++;
+
+ smp_local_timer_interrupt();
+}
+#endif
+
+void smp_send_timer_broadcast_ipi(void)
+{
+ cpumask_t mask;
+
+ cpus_and(mask, cpu_online_map, timer_bcast_ipi);
+ if (!cpus_empty(mask)) {
+#ifdef CONFIG_SMP
+ send_IPI_mask(mask, LOCAL_TIMER_VECTOR);
#else
- /* Disable focus processor (bit==1) */
- value |= APIC_SPIV_FOCUS_DISABLED;
+ /*
+ * We can directly call the apic timer interrupt handler
+ * in UP case. Minus all irq related functions
+ */
+ up_apic_timer_interrupt_call();
#endif
- /*
- * Set spurious IRQ vector
- */
- value |= SPURIOUS_APIC_VECTOR;
- apic_write_around(APIC_SPIV, value);
+ }
+}
+
+int setup_profiling_timer(unsigned int multiplier)
+{
+ return -EINVAL;
+}
+
+/*
+ * Local APIC start and shutdown
+ */
+
+/**
+ * clear_local_APIC - shutdown the local APIC
+ *
+ * This is called, when a CPU is disabled and before rebooting, so the state of
+ * the local APIC has no dangling leftovers. Also used to cleanout any BIOS
+ * leftovers during boot.
+ */
+void clear_local_APIC(void)
+{
+ int maxlvt = lapic_get_maxlvt();
+ unsigned long v;
/*
- * Set up LVT0, LVT1:
- *
- * set up through-local-APIC on the BP's LINT0. This is not
- * strictly necessery in pure symmetric-IO mode, but sometimes
- * we delegate interrupts to the 8259A.
+ * Masking an LVT entry can trigger a local APIC error
+ * if the vector is zero. Mask LVTERR first to prevent this.
*/
+ if (maxlvt >= 3) {
+ v = ERROR_APIC_VECTOR; /* any non-zero vector will do */
+ apic_write_around(APIC_LVTERR, v | APIC_LVT_MASKED);
+ }
/*
- * TODO: set up through-local-APIC from through-I/O-APIC? --macro
+ * Careful: we have to set masks only first to deassert
+ * any level-triggered sources.
*/
- value = apic_read(APIC_LVT0) & APIC_LVT_MASKED;
- if (!smp_processor_id() && (pic_mode || !value)) {
- value = APIC_DM_EXTINT;
- apic_printk(APIC_VERBOSE, "enabled ExtINT on CPU#%d\n",
- smp_processor_id());
- } else {
- value = APIC_DM_EXTINT | APIC_LVT_MASKED;
- apic_printk(APIC_VERBOSE, "masked ExtINT on CPU#%d\n",
- smp_processor_id());
+ v = apic_read(APIC_LVTT);
+ apic_write_around(APIC_LVTT, v | APIC_LVT_MASKED);
+ v = apic_read(APIC_LVT0);
+ apic_write_around(APIC_LVT0, v | APIC_LVT_MASKED);
+ v = apic_read(APIC_LVT1);
+ apic_write_around(APIC_LVT1, v | APIC_LVT_MASKED);
+ if (maxlvt >= 4) {
+ v = apic_read(APIC_LVTPC);
+ apic_write_around(APIC_LVTPC, v | APIC_LVT_MASKED);
}
- apic_write_around(APIC_LVT0, value);
+ /* lets not touch this if we didn't frob it */
+#ifdef CONFIG_X86_MCE_P4THERMAL
+ if (maxlvt >= 5) {
+ v = apic_read(APIC_LVTTHMR);
+ apic_write_around(APIC_LVTTHMR, v | APIC_LVT_MASKED);
+ }
+#endif
/*
- * only the BP should see the LINT1 NMI signal, obviously.
+ * Clean APIC state for other OSs:
*/
- if (!smp_processor_id())
- value = APIC_DM_NMI;
- else
- value = APIC_DM_NMI | APIC_LVT_MASKED;
- if (!APIC_INTEGRATED(ver)) /* 82489DX */
- value |= APIC_LVT_LEVEL_TRIGGER;
- apic_write_around(APIC_LVT1, value);
-
- if (APIC_INTEGRATED(ver) && !esr_disable) { /* !82489DX */
- maxlvt = get_maxlvt();
- if (maxlvt > 3) /* Due to the Pentium erratum 3AP. */
- apic_write(APIC_ESR, 0);
- oldvalue = apic_read(APIC_ESR);
+ apic_write_around(APIC_LVTT, APIC_LVT_MASKED);
+ apic_write_around(APIC_LVT0, APIC_LVT_MASKED);
+ apic_write_around(APIC_LVT1, APIC_LVT_MASKED);
+ if (maxlvt >= 3)
+ apic_write_around(APIC_LVTERR, APIC_LVT_MASKED);
+ if (maxlvt >= 4)
+ apic_write_around(APIC_LVTPC, APIC_LVT_MASKED);
- value = ERROR_APIC_VECTOR; // enables sending errors
- apic_write_around(APIC_LVTERR, value);
- /*
- * spec says clear errors after enabling vector.
- */
+#ifdef CONFIG_X86_MCE_P4THERMAL
+ if (maxlvt >= 5)
+ apic_write_around(APIC_LVTTHMR, APIC_LVT_MASKED);
+#endif
+ /* Integrated APIC (!82489DX) ? */
+ if (lapic_is_integrated()) {
if (maxlvt > 3)
+ /* Clear ESR due to Pentium errata 3AP and 11AP */
apic_write(APIC_ESR, 0);
- value = apic_read(APIC_ESR);
- if (value != oldvalue)
- apic_printk(APIC_VERBOSE, "ESR value before enabling "
- "vector: 0x%08lx after: 0x%08lx\n",
- oldvalue, value);
- } else {
- if (esr_disable)
- /*
- * Something untraceble is creating bad interrupts on
- * secondary quads ... for the moment, just leave the
- * ESR disabled - we can't do anything useful with the
- * errors anyway - mbligh
- */
- printk("Leaving ESR disabled.\n");
- else
- printk("No ESR for 82489DX.\n");
+ apic_read(APIC_ESR);
}
+}
- setup_apic_nmi_watchdog(NULL);
- apic_pm_activate();
+/**
+ * disable_local_APIC - clear and disable the local APIC
+ */
+void disable_local_APIC(void)
+{
+ unsigned long value;
+
+ clear_local_APIC();
+
+ /*
+ * Disable APIC (implies clearing of registers
+ * for 82489DX!).
+ */
+ value = apic_read(APIC_SPIV);
+ value &= ~APIC_SPIV_APIC_ENABLED;
+ apic_write_around(APIC_SPIV, value);
+
+ /*
+ * When LAPIC was disabled by the BIOS and enabled by the kernel,
+ * restore the disabled state.
+ */
+ if (enabled_via_apicbase) {
+ unsigned int l, h;
+
+ rdmsr(MSR_IA32_APICBASE, l, h);
+ l &= ~MSR_IA32_APICBASE_ENABLE;
+ wrmsr(MSR_IA32_APICBASE, l, h);
+ }
}
/*
- * If Linux enabled the LAPIC against the BIOS default
- * disable it down before re-entering the BIOS on shutdown.
- * Otherwise the BIOS may get confused and not power-off.
- * Additionally clear all LVT entries before disable_local_APIC
+ * If Linux enabled the LAPIC against the BIOS default disable it down before
+ * re-entering the BIOS on shutdown. Otherwise the BIOS may get confused and
+ * not power-off. Additionally clear all LVT entries before disable_local_APIC
* for the case where Linux didn't enable the LAPIC.
*/
void lapic_shutdown(void)
@@ -624,666 +629,519 @@ void lapic_shutdown(void)
local_irq_restore(flags);
}
-#ifdef CONFIG_PM
-
-static struct {
- int active;
- /* r/w apic fields */
- unsigned int apic_id;
- unsigned int apic_taskpri;
- unsigned int apic_ldr;
- unsigned int apic_dfr;
- unsigned int apic_spiv;
- unsigned int apic_lvtt;
- unsigned int apic_lvtpc;
- unsigned int apic_lvt0;
- unsigned int apic_lvt1;
- unsigned int apic_lvterr;
- unsigned int apic_tmict;
- unsigned int apic_tdcr;
- unsigned int apic_thmr;
-} apic_pm_state;
-
-static int lapic_suspend(struct sys_device *dev, pm_message_t state)
+/*
+ * This is to verify that we're looking at a real local APIC.
+ * Check these against your board if the CPUs aren't getting
+ * started for no apparent reason.
+ */
+int __init verify_local_APIC(void)
{
- unsigned long flags;
+ unsigned int reg0, reg1;
- if (!apic_pm_state.active)
+ /*
+ * The version register is read-only in a real APIC.
+ */
+ reg0 = apic_read(APIC_LVR);
+ apic_printk(APIC_DEBUG, "Getting VERSION: %x\n", reg0);
+ apic_write(APIC_LVR, reg0 ^ APIC_LVR_MASK);
+ reg1 = apic_read(APIC_LVR);
+ apic_printk(APIC_DEBUG, "Getting VERSION: %x\n", reg1);
+
+ /*
+ * The two version reads above should print the same
+ * numbers. If the second one is different, then we
+ * poke at a non-APIC.
+ */
+ if (reg1 != reg0)
return 0;
- apic_pm_state.apic_id = apic_read(APIC_ID);
- apic_pm_state.apic_taskpri = apic_read(APIC_TASKPRI);
- apic_pm_state.apic_ldr = apic_read(APIC_LDR);
- apic_pm_state.apic_dfr = apic_read(APIC_DFR);
- apic_pm_state.apic_spiv = apic_read(APIC_SPIV);
- apic_pm_state.apic_lvtt = apic_read(APIC_LVTT);
- apic_pm_state.apic_lvtpc = apic_read(APIC_LVTPC);
- apic_pm_state.apic_lvt0 = apic_read(APIC_LVT0);
- apic_pm_state.apic_lvt1 = apic_read(APIC_LVT1);
- apic_pm_state.apic_lvterr = apic_read(APIC_LVTERR);
- apic_pm_state.apic_tmict = apic_read(APIC_TMICT);
- apic_pm_state.apic_tdcr = apic_read(APIC_TDCR);
- apic_pm_state.apic_thmr = apic_read(APIC_LVTTHMR);
-
- local_irq_save(flags);
- disable_local_APIC();
- local_irq_restore(flags);
- return 0;
-}
-
-static int lapic_resume(struct sys_device *dev)
-{
- unsigned int l, h;
- unsigned long flags;
-
- if (!apic_pm_state.active)
- return 0;
-
- local_irq_save(flags);
-
/*
- * Make sure the APICBASE points to the right address
- *
- * FIXME! This will be wrong if we ever support suspend on
- * SMP! We'll need to do this as part of the CPU restore!
+ * Check if the version looks reasonably.
*/
- rdmsr(MSR_IA32_APICBASE, l, h);
- l &= ~MSR_IA32_APICBASE_BASE;
- l |= MSR_IA32_APICBASE_ENABLE | mp_lapic_addr;
- wrmsr(MSR_IA32_APICBASE, l, h);
-
- apic_write(APIC_LVTERR, ERROR_APIC_VECTOR | APIC_LVT_MASKED);
- apic_write(APIC_ID, apic_pm_state.apic_id);
- apic_write(APIC_DFR, apic_pm_state.apic_dfr);
- apic_write(APIC_LDR, apic_pm_state.apic_ldr);
- apic_write(APIC_TASKPRI, apic_pm_state.apic_taskpri);
- apic_write(APIC_SPIV, apic_pm_state.apic_spiv);
- apic_write(APIC_LVT0, apic_pm_state.apic_lvt0);
- apic_write(APIC_LVT1, apic_pm_state.apic_lvt1);
- apic_write(APIC_LVTTHMR, apic_pm_state.apic_thmr);
- apic_write(APIC_LVTPC, apic_pm_state.apic_lvtpc);
- apic_write(APIC_LVTT, apic_pm_state.apic_lvtt);
- apic_write(APIC_TDCR, apic_pm_state.apic_tdcr);
- apic_write(APIC_TMICT, apic_pm_state.apic_tmict);
- apic_write(APIC_ESR, 0);
- apic_read(APIC_ESR);
- apic_write(APIC_LVTERR, apic_pm_state.apic_lvterr);
- apic_write(APIC_ESR, 0);
- apic_read(APIC_ESR);
- local_irq_restore(flags);
- return 0;
-}
-
-/*
- * This device has no shutdown method - fully functioning local APICs
- * are needed on every CPU up until machine_halt/restart/poweroff.
- */
-
-static struct sysdev_class lapic_sysclass = {
- set_kset_name("lapic"),
- .resume = lapic_resume,
- .suspend = lapic_suspend,
-};
-
-static struct sys_device device_lapic = {
- .id = 0,
- .cls = &lapic_sysclass,
-};
-
-static void __devinit apic_pm_activate(void)
-{
- apic_pm_state.active = 1;
-}
-
-static int __init init_lapic_sysfs(void)
-{
- int error;
-
- if (!cpu_has_apic)
+ reg1 = GET_APIC_VERSION(reg0);
+ if (reg1 == 0x00 || reg1 == 0xff)
+ return 0;
+ reg1 = lapic_get_maxlvt();
+ if (reg1 < 0x02 || reg1 == 0xff)
return 0;
- /* XXX: remove suspend/resume procs if !apic_pm_state.active? */
-
- error = sysdev_class_register(&lapic_sysclass);
- if (!error)
- error = sysdev_register(&device_lapic);
- return error;
-}
-device_initcall(init_lapic_sysfs);
-
-#else /* CONFIG_PM */
-
-static void apic_pm_activate(void) { }
-
-#endif /* CONFIG_PM */
-
-/*
- * Detect and enable local APICs on non-SMP boards.
- * Original code written by Keir Fraser.
- */
-
-static int __init apic_set_verbosity(char *str)
-{
- if (strcmp("debug", str) == 0)
- apic_verbosity = APIC_DEBUG;
- else if (strcmp("verbose", str) == 0)
- apic_verbosity = APIC_VERBOSE;
- return 1;
-}
-
-__setup("apic=", apic_set_verbosity);
-
-static int __init detect_init_APIC (void)
-{
- u32 h, l, features;
-
- /* Disabled by kernel option? */
- if (enable_local_apic < 0)
- return -1;
-
- switch (boot_cpu_data.x86_vendor) {
- case X86_VENDOR_AMD:
- if ((boot_cpu_data.x86 == 6 && boot_cpu_data.x86_model > 1) ||
- (boot_cpu_data.x86 == 15))
- break;
- goto no_apic;
- case X86_VENDOR_INTEL:
- if (boot_cpu_data.x86 == 6 || boot_cpu_data.x86 == 15 ||
- (boot_cpu_data.x86 == 5 && cpu_has_apic))
- break;
- goto no_apic;
- default:
- goto no_apic;
- }
-
- if (!cpu_has_apic) {
- /*
- * Over-ride BIOS and try to enable the local
- * APIC only if "lapic" specified.
- */
- if (enable_local_apic <= 0) {
- printk("Local APIC disabled by BIOS -- "
- "you can enable it with \"lapic\"\n");
- return -1;
- }
- /*
- * Some BIOSes disable the local APIC in the
- * APIC_BASE MSR. This can only be done in
- * software for Intel P6 or later and AMD K7
- * (Model > 1) or later.
- */
- rdmsr(MSR_IA32_APICBASE, l, h);
- if (!(l & MSR_IA32_APICBASE_ENABLE)) {
- printk("Local APIC disabled by BIOS -- reenabling.\n");
- l &= ~MSR_IA32_APICBASE_BASE;
- l |= MSR_IA32_APICBASE_ENABLE | APIC_DEFAULT_PHYS_BASE;
- wrmsr(MSR_IA32_APICBASE, l, h);
- enabled_via_apicbase = 1;
- }
- }
- /*
- * The APIC feature bit should now be enabled
- * in `cpuid'
- */
- features = cpuid_edx(1);
- if (!(features & (1 << X86_FEATURE_APIC))) {
- printk("Could not enable APIC!\n");
- return -1;
- }
- set_bit(X86_FEATURE_APIC, boot_cpu_data.x86_capability);
- mp_lapic_addr = APIC_DEFAULT_PHYS_BASE;
-
- /* The BIOS may have set up the APIC at some other address */
- rdmsr(MSR_IA32_APICBASE, l, h);
- if (l & MSR_IA32_APICBASE_ENABLE)
- mp_lapic_addr = l & MSR_IA32_APICBASE_BASE;
-
- if (nmi_watchdog != NMI_NONE)
- nmi_watchdog = NMI_LOCAL_APIC;
-
- printk("Found and enabled local APIC!\n");
-
- apic_pm_activate();
-
- return 0;
-
-no_apic:
- printk("No local APIC present or hardware disabled\n");
- return -1;
-}
-
-void __init init_apic_mappings(void)
-{
- unsigned long apic_phys;
/*
- * If no local APIC can be found then set up a fake all
- * zeroes page to simulate the local APIC and another
- * one for the IO-APIC.
+ * The ID register is read/write in a real APIC.
*/
- if (!smp_found_config && detect_init_APIC()) {
- apic_phys = (unsigned long) alloc_bootmem_pages(PAGE_SIZE);
- apic_phys = __pa(apic_phys);
- } else
- apic_phys = mp_lapic_addr;
-
- set_fixmap_nocache(FIX_APIC_BASE, apic_phys);
- printk(KERN_DEBUG "mapped APIC to %08lx (%08lx)\n", APIC_BASE,
- apic_phys);
+ reg0 = apic_read(APIC_ID);
+ apic_printk(APIC_DEBUG, "Getting ID: %x\n", reg0);
/*
- * Fetch the APIC ID of the BSP in case we have a
- * default configuration (or the MP table is broken).
+ * The next two are just to see if we have sane values.
+ * They're only really relevant if we're in Virtual Wire
+ * compatibility mode, but most boxes are anymore.
*/
- if (boot_cpu_physical_apicid == -1U)
- boot_cpu_physical_apicid = GET_APIC_ID(apic_read(APIC_ID));
-
-#ifdef CONFIG_X86_IO_APIC
- {
- unsigned long ioapic_phys, idx = FIX_IO_APIC_BASE_0;
- int i;
-
- for (i = 0; i < nr_ioapics; i++) {
- if (smp_found_config) {
- ioapic_phys = mp_ioapics[i].mpc_apicaddr;
- 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;
- }
- } else {
-fake_ioapic_page:
- ioapic_phys = (unsigned long)
- alloc_bootmem_pages(PAGE_SIZE);
- ioapic_phys = __pa(ioapic_phys);
- }
- set_fixmap_nocache(idx, ioapic_phys);
- printk(KERN_DEBUG "mapped IOAPIC to %08lx (%08lx)\n",
- __fix_to_virt(idx), ioapic_phys);
- idx++;
- }
- }
-#endif
-}
-
-/*
- * This part sets up the APIC 32 bit clock in LVTT1, with HZ interrupts
- * per second. We assume that the caller has already set up the local
- * APIC.
- *
- * The APIC timer is not exactly sync with the external timer chip, it
- * closely follows bus clocks.
- */
-
-/*
- * The timer chip is already set up at HZ interrupts per second here,
- * but we do not accept timer interrupts yet. We only allow the BP
- * to calibrate.
- */
-static unsigned int __devinit get_8254_timer_count(void)
-{
- unsigned long flags;
-
- unsigned int count;
-
- spin_lock_irqsave(&i8253_lock, flags);
-
- outb_p(0x00, PIT_MODE);
- count = inb_p(PIT_CH0);
- count |= inb_p(PIT_CH0) << 8;
-
- spin_unlock_irqrestore(&i8253_lock, flags);
-
- return count;
-}
-
-/* next tick in 8254 can be caught by catching timer wraparound */
-static void __devinit wait_8254_wraparound(void)
-{
- unsigned int curr_count, prev_count;
-
- curr_count = get_8254_timer_count();
- do {
- prev_count = curr_count;
- curr_count = get_8254_timer_count();
-
- /* workaround for broken Mercury/Neptune */
- if (prev_count >= curr_count + 0x100)
- curr_count = get_8254_timer_count();
-
- } while (prev_count >= curr_count);
-}
-
-/*
- * Default initialization for 8254 timers. If we use other timers like HPET,
- * we override this later
- */
-void (*wait_timer_tick)(void) __devinitdata = wait_8254_wraparound;
-
-/*
- * This function sets up the local APIC timer, with a timeout of
- * 'clocks' APIC bus clock. During calibration we actually call
- * this function twice on the boot CPU, once with a bogus timeout
- * value, second time for real. The other (noncalibrating) CPUs
- * call this function only once, with the real, calibrated value.
- *
- * We do reads before writes even if unnecessary, to get around the
- * P5 APIC double write bug.
- */
-
-#define APIC_DIVISOR 16
-
-static void __setup_APIC_LVTT(unsigned int clocks)
-{
- unsigned int lvtt_value, tmp_value, ver;
- int cpu = smp_processor_id();
-
- ver = GET_APIC_VERSION(apic_read(APIC_LVR));
- lvtt_value = APIC_LVT_TIMER_PERIODIC | LOCAL_TIMER_VECTOR;
- if (!APIC_INTEGRATED(ver))
- lvtt_value |= SET_APIC_TIMER_BASE(APIC_TIMER_BASE_DIV);
-
- if (cpu_isset(cpu, timer_bcast_ipi))
- lvtt_value |= APIC_LVT_MASKED;
+ reg0 = apic_read(APIC_LVT0);
+ apic_printk(APIC_DEBUG, "Getting LVT0: %x\n", reg0);
+ reg1 = apic_read(APIC_LVT1);
+ apic_printk(APIC_DEBUG, "Getting LVT1: %x\n", reg1);
- apic_write_around(APIC_LVTT, lvtt_value);
+ return 1;
+}
+/**
+ * sync_Arb_IDs - synchronize APIC bus arbitration IDs
+ */
+void __init sync_Arb_IDs(void)
+{
/*
- * Divide PICLK by 16
+ * Unsupported on P4 - see Intel Dev. Manual Vol. 3, Ch. 8.6.1 And not
+ * needed on AMD.
*/
- tmp_value = apic_read(APIC_TDCR);
- apic_write_around(APIC_TDCR, (tmp_value
- & ~(APIC_TDR_DIV_1 | APIC_TDR_DIV_TMBASE))
- | APIC_TDR_DIV_16);
+ if (modern_apic())
+ return;
+ /*
+ * Wait for idle.
+ */
+ apic_wait_icr_idle();
- apic_write_around(APIC_TMICT, clocks/APIC_DIVISOR);
+ apic_printk(APIC_DEBUG, "Synchronizing Arb IDs.\n");
+ apic_write_around(APIC_ICR, APIC_DEST_ALLINC | APIC_INT_LEVELTRIG
+ | APIC_DM_INIT);
}
-static void __devinit setup_APIC_timer(unsigned int clocks)
+/*
+ * An initial setup of the virtual wire mode.
+ */
+void __init init_bsp_APIC(void)
{
- unsigned long flags;
+ unsigned long value;
- local_irq_save(flags);
+ /*
+ * Don't do the setup now if we have a SMP BIOS as the
+ * through-I/O-APIC virtual wire mode might be active.
+ */
+ if (smp_found_config || !cpu_has_apic)
+ return;
/*
- * Wait for IRQ0's slice:
+ * Do not trust the local APIC being empty at bootup.
*/
- wait_timer_tick();
+ clear_local_APIC();
- __setup_APIC_LVTT(clocks);
+ /*
+ * Enable APIC.
+ */
+ value = apic_read(APIC_SPIV);
+ value &= ~APIC_VECTOR_MASK;
+ value |= APIC_SPIV_APIC_ENABLED;
- local_irq_restore(flags);
+ /* This bit is reserved on P4/Xeon and should be cleared */
+ if ((boot_cpu_data.x86_vendor == X86_VENDOR_INTEL) &&
+ (boot_cpu_data.x86 == 15))
+ value &= ~APIC_SPIV_FOCUS_DISABLED;
+ else
+ value |= APIC_SPIV_FOCUS_DISABLED;
+ value |= SPURIOUS_APIC_VECTOR;
+ apic_write_around(APIC_SPIV, value);
+
+ /*
+ * Set up the virtual wire mode.
+ */
+ apic_write_around(APIC_LVT0, APIC_DM_EXTINT);
+ value = APIC_DM_NMI;
+ if (!lapic_is_integrated()) /* 82489DX */
+ value |= APIC_LVT_LEVEL_TRIGGER;
+ apic_write_around(APIC_LVT1, value);
}
-/*
- * In this function we calibrate APIC bus clocks to the external
- * timer. Unfortunately we cannot use jiffies and the timer irq
- * to calibrate, since some later bootup code depends on getting
- * the first irq? Ugh.
- *
- * We want to do the calibration only once since we
- * want to have local timer irqs syncron. CPUs connected
- * by the same APIC bus have the very same bus frequency.
- * And we want to have irqs off anyways, no accidental
- * APIC irq that way.
+/**
+ * setup_local_APIC - setup the local APIC
*/
-
-static int __init calibrate_APIC_clock(void)
+void __devinit setup_local_APIC(void)
{
- unsigned long long t1 = 0, t2 = 0;
- long tt1, tt2;
- long result;
- int i;
- const int LOOPS = HZ/10;
+ unsigned long oldvalue, value, maxlvt, integrated;
+ int i, j;
- apic_printk(APIC_VERBOSE, "calibrating APIC timer ...\n");
+ /* 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);
+ }
+
+ integrated = lapic_is_integrated();
/*
- * Put whatever arbitrary (but long enough) timeout
- * value into the APIC clock, we just want to get the
- * counter running for calibration.
+ * Double-check whether this APIC is really registered.
*/
- __setup_APIC_LVTT(1000000000);
+ if (!apic_id_registered())
+ BUG();
/*
- * The timer chip counts down to zero. Let's wait
- * for a wraparound to start exact measurement:
- * (the current tick might have been already half done)
+ * Intel recommends to set DFR, LDR and TPR before enabling
+ * an APIC. See e.g. "AP-388 82489DX User's Manual" (Intel
+ * document number 292116). So here it goes...
*/
-
- wait_timer_tick();
+ init_apic_ldr();
/*
- * We wrapped around just now. Let's start:
+ * Set Task Priority to 'accept all'. We never change this
+ * later on.
*/
- if (cpu_has_tsc)
- rdtscll(t1);
- tt1 = apic_read(APIC_TMCCT);
+ value = apic_read(APIC_TASKPRI);
+ value &= ~APIC_TPRI_MASK;
+ apic_write_around(APIC_TASKPRI, value);
/*
- * Let's wait LOOPS wraprounds:
+ * After a crash, we no longer service the interrupts and a pending
+ * interrupt from previous kernel might still have ISR bit set.
+ *
+ * Most probably by now CPU has serviced that pending interrupt and
+ * it might not have done the ack_APIC_irq() because it thought,
+ * interrupt came from i8259 as ExtInt. LAPIC did not get EOI so it
+ * does not clear the ISR bit and cpu thinks it has already serivced
+ * the interrupt. Hence a vector might get locked. It was noticed
+ * for timer irq (vector 0x31). Issue an extra EOI to clear ISR.
*/
- for (i = 0; i < LOOPS; i++)
- wait_timer_tick();
+ for (i = APIC_ISR_NR - 1; i >= 0; i--) {
+ value = apic_read(APIC_ISR + i*0x10);
+ for (j = 31; j >= 0; j--) {
+ if (value & (1<<j))
+ ack_APIC_irq();
+ }
+ }
- tt2 = apic_read(APIC_TMCCT);
- if (cpu_has_tsc)
- rdtscll(t2);
+ /*
+ * Now that we are all set up, enable the APIC
+ */
+ value = apic_read(APIC_SPIV);
+ value &= ~APIC_VECTOR_MASK;
+ /*
+ * Enable APIC
+ */
+ value |= APIC_SPIV_APIC_ENABLED;
/*
- * The APIC bus clock counter is 32 bits only, it
- * might have overflown, but note that we use signed
- * longs, thus no extra care needed.
+ * 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 :-(
*
- * underflown to be exact, as the timer counts down ;)
+ * [ 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
*/
- result = (tt1-tt2)*APIC_DIVISOR/LOOPS;
-
- if (cpu_has_tsc)
- apic_printk(APIC_VERBOSE, "..... CPU clock speed is "
- "%ld.%04ld MHz.\n",
- ((long)(t2-t1)/LOOPS)/(1000000/HZ),
- ((long)(t2-t1)/LOOPS)%(1000000/HZ));
-
- apic_printk(APIC_VERBOSE, "..... host bus clock speed is "
- "%ld.%04ld MHz.\n",
- result/(1000000/HZ),
- result%(1000000/HZ));
-
- return result;
-}
-
-static unsigned int calibration_result;
-
-void __init setup_boot_APIC_clock(void)
-{
- unsigned long flags;
- apic_printk(APIC_VERBOSE, "Using local APIC timer interrupts.\n");
- using_apic_timer = 1;
-
- local_irq_save(flags);
+ /* Enable focus processor (bit==0) */
+ value &= ~APIC_SPIV_FOCUS_DISABLED;
- calibration_result = calibrate_APIC_clock();
/*
- * Now set up the timer for real.
+ * Set spurious IRQ vector
*/
- setup_APIC_timer(calibration_result);
+ value |= SPURIOUS_APIC_VECTOR;
+ apic_write_around(APIC_SPIV, value);
- local_irq_restore(flags);
-}
+ /*
+ * Set up LVT0, LVT1:
+ *
+ * set up through-local-APIC on the BP's LINT0. This is not
+ * strictly necessery in pure symmetric-IO mode, but sometimes
+ * we delegate interrupts to the 8259A.
+ */
+ /*
+ * TODO: set up through-local-APIC from through-I/O-APIC? --macro
+ */
+ value = apic_read(APIC_LVT0) & APIC_LVT_MASKED;
+ if (!smp_processor_id() && (pic_mode || !value)) {
+ value = APIC_DM_EXTINT;
+ apic_printk(APIC_VERBOSE, "enabled ExtINT on CPU#%d\n",
+ smp_processor_id());
+ } else {
+ value = APIC_DM_EXTINT | APIC_LVT_MASKED;
+ apic_printk(APIC_VERBOSE, "masked ExtINT on CPU#%d\n",
+ smp_processor_id());
+ }
+ apic_write_around(APIC_LVT0, value);
-void __devinit setup_secondary_APIC_clock(void)
-{
- setup_APIC_timer(calibration_result);
-}
+ /*
+ * only the BP should see the LINT1 NMI signal, obviously.
+ */
+ if (!smp_processor_id())
+ value = APIC_DM_NMI;
+ else
+ value = APIC_DM_NMI | APIC_LVT_MASKED;
+ if (!integrated) /* 82489DX */
+ value |= APIC_LVT_LEVEL_TRIGGER;
+ apic_write_around(APIC_LVT1, value);
-void disable_APIC_timer(void)
-{
- if (using_apic_timer) {
- unsigned long v;
+ if (integrated && !esr_disable) { /* !82489DX */
+ maxlvt = lapic_get_maxlvt();
+ if (maxlvt > 3) /* Due to the Pentium erratum 3AP. */
+ apic_write(APIC_ESR, 0);
+ oldvalue = apic_read(APIC_ESR);
- v = apic_read(APIC_LVTT);
+ /* enables sending errors */
+ value = ERROR_APIC_VECTOR;
+ apic_write_around(APIC_LVTERR, value);
/*
- * When an illegal vector value (0-15) is written to an LVT
- * entry and delivery mode is Fixed, the APIC may signal an
- * illegal vector error, with out regard to whether the mask
- * bit is set or whether an interrupt is actually seen on input.
- *
- * Boot sequence might call this function when the LVTT has
- * '0' vector value. So make sure vector field is set to
- * valid value.
+ * spec says clear errors after enabling vector.
*/
- v |= (APIC_LVT_MASKED | LOCAL_TIMER_VECTOR);
- apic_write_around(APIC_LVTT, v);
+ if (maxlvt > 3)
+ apic_write(APIC_ESR, 0);
+ value = apic_read(APIC_ESR);
+ if (value != oldvalue)
+ apic_printk(APIC_VERBOSE, "ESR value before enabling "
+ "vector: 0x%08lx after: 0x%08lx\n",
+ oldvalue, value);
+ } else {
+ if (esr_disable)
+ /*
+ * Something untraceble is creating bad interrupts on
+ * secondary quads ... for the moment, just leave the
+ * ESR disabled - we can't do anything useful with the
+ * errors anyway - mbligh
+ */
+ printk(KERN_INFO "Leaving ESR disabled.\n");
+ else
+ printk(KERN_INFO "No ESR for 82489DX.\n");
}
+
+ setup_apic_nmi_watchdog(NULL);
+ apic_pm_activate();
}
-void enable_APIC_timer(void)
+/*
+ * Detect and initialize APIC
+ */
+static int __init detect_init_APIC (void)
{
- int cpu = smp_processor_id();
+ u32 h, l, features;
- if (using_apic_timer &&
- !cpu_isset(cpu, timer_bcast_ipi)) {
- unsigned long v;
+ /* Disabled by kernel option? */
+ if (enable_local_apic < 0)
+ return -1;
- v = apic_read(APIC_LVTT);
- apic_write_around(APIC_LVTT, v & ~APIC_LVT_MASKED);
+ switch (boot_cpu_data.x86_vendor) {
+ case X86_VENDOR_AMD:
+ if ((boot_cpu_data.x86 == 6 && boot_cpu_data.x86_model > 1) ||
+ (boot_cpu_data.x86 == 15))
+ break;
+ goto no_apic;
+ case X86_VENDOR_INTEL:
+ if (boot_cpu_data.x86 == 6 || boot_cpu_data.x86 == 15 ||
+ (boot_cpu_data.x86 == 5 && cpu_has_apic))
+ break;
+ goto no_apic;
+ default:
+ goto no_apic;
}
-}
-
-void switch_APIC_timer_to_ipi(void *cpumask)
-{
- cpumask_t mask = *(cpumask_t *)cpumask;
- int cpu = smp_processor_id();
- if (cpu_isset(cpu, mask) &&
- !cpu_isset(cpu, timer_bcast_ipi)) {
- disable_APIC_timer();
- cpu_set(cpu, timer_bcast_ipi);
+ if (!cpu_has_apic) {
+ /*
+ * Over-ride BIOS and try to enable the local APIC only if
+ * "lapic" specified.
+ */
+ if (enable_local_apic <= 0) {
+ printk(KERN_INFO "Local APIC disabled by BIOS -- "
+ "you can enable it with \"lapic\"\n");
+ return -1;
+ }
+ /*
+ * Some BIOSes disable the local APIC in the APIC_BASE
+ * MSR. This can only be done in software for Intel P6 or later
+ * and AMD K7 (Model > 1) or later.
+ */
+ rdmsr(MSR_IA32_APICBASE, l, h);
+ if (!(l & MSR_IA32_APICBASE_ENABLE)) {
+ printk(KERN_INFO
+ "Local APIC disabled by BIOS -- reenabling.\n");
+ l &= ~MSR_IA32_APICBASE_BASE;
+ l |= MSR_IA32_APICBASE_ENABLE | APIC_DEFAULT_PHYS_BASE;
+ wrmsr(MSR_IA32_APICBASE, l, h);
+ enabled_via_apicbase = 1;
+ }
}
-}
-EXPORT_SYMBOL(switch_APIC_timer_to_ipi);
+ /*
+ * The APIC feature bit should now be enabled
+ * in `cpuid'
+ */
+ features = cpuid_edx(1);
+ if (!(features & (1 << X86_FEATURE_APIC))) {
+ printk(KERN_WARNING "Could not enable APIC!\n");
+ return -1;
+ }
+ set_bit(X86_FEATURE_APIC, boot_cpu_data.x86_capability);
+ mp_lapic_addr = APIC_DEFAULT_PHYS_BASE;
-void switch_ipi_to_APIC_timer(void *cpumask)
-{
- cpumask_t mask = *(cpumask_t *)cpumask;
- int cpu = smp_processor_id();
+ /* The BIOS may have set up the APIC at some other address */
+ rdmsr(MSR_IA32_APICBASE, l, h);
+ if (l & MSR_IA32_APICBASE_ENABLE)
+ mp_lapic_addr = l & MSR_IA32_APICBASE_BASE;
- if (cpu_isset(cpu, mask) &&
- cpu_isset(cpu, timer_bcast_ipi)) {
- cpu_clear(cpu, timer_bcast_ipi);
- enable_APIC_timer();
- }
-}
-EXPORT_SYMBOL(switch_ipi_to_APIC_timer);
+ if (nmi_watchdog != NMI_NONE)
+ nmi_watchdog = NMI_LOCAL_APIC;
-#undef APIC_DIVISOR
+ printk(KERN_INFO "Found and enabled local APIC!\n");
-/*
- * Local timer interrupt handler. It does both profiling and
- * process statistics/rescheduling.
- *
- * We do profiling in every local tick, statistics/rescheduling
- * happen only every 'profiling multiplier' ticks. The default
- * multiplier is 1 and it can be changed by writing the new multiplier
- * value into /proc/profile.
- */
+ apic_pm_activate();
-inline void smp_local_timer_interrupt(void)
-{
- profile_tick(CPU_PROFILING);
-#ifdef CONFIG_SMP
- update_process_times(user_mode_vm(get_irq_regs()));
-#endif
+ return 0;
- /*
- * We take the 'long' return path, and there every subsystem
- * grabs the apropriate 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.
- */
+no_apic:
+ printk(KERN_INFO "No local APIC present or hardware disabled\n");
+ return -1;
}
-/*
- * 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 ... ]
+/**
+ * init_apic_mappings - initialize APIC mappings
*/
-
-fastcall void smp_apic_timer_interrupt(struct pt_regs *regs)
+void __init init_apic_mappings(void)
{
- struct pt_regs *old_regs = set_irq_regs(regs);
- int cpu = smp_processor_id();
+ unsigned long apic_phys;
/*
- * the NMI deadlock-detector uses this.
+ * If no local APIC can be found then set up a fake all
+ * zeroes page to simulate the local APIC and another
+ * one for the IO-APIC.
*/
- per_cpu(irq_stat, cpu).apic_timer_irqs++;
+ if (!smp_found_config && detect_init_APIC()) {
+ apic_phys = (unsigned long) alloc_bootmem_pages(PAGE_SIZE);
+ apic_phys = __pa(apic_phys);
+ } else
+ apic_phys = mp_lapic_addr;
+
+ set_fixmap_nocache(FIX_APIC_BASE, apic_phys);
+ printk(KERN_DEBUG "mapped APIC to %08lx (%08lx)\n", APIC_BASE,
+ apic_phys);
/*
- * 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.
+ * Fetch the APIC ID of the BSP in case we have a
+ * default configuration (or the MP table is broken).
*/
- irq_enter();
- smp_local_timer_interrupt();
- irq_exit();
- set_irq_regs(old_regs);
+ if (boot_cpu_physical_apicid == -1U)
+ boot_cpu_physical_apicid = GET_APIC_ID(apic_read(APIC_ID));
+
+#ifdef CONFIG_X86_IO_APIC
+ {
+ unsigned long ioapic_phys, idx = FIX_IO_APIC_BASE_0;
+ int i;
+
+ for (i = 0; i < nr_ioapics; i++) {
+ if (smp_found_config) {
+ ioapic_phys = mp_ioapics[i].mpc_apicaddr;
+ 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;
+ }
+ } else {
+fake_ioapic_page:
+ ioapic_phys = (unsigned long)
+ alloc_bootmem_pages(PAGE_SIZE);
+ ioapic_phys = __pa(ioapic_phys);
+ }
+ set_fixmap_nocache(idx, ioapic_phys);
+ printk(KERN_DEBUG "mapped IOAPIC to %08lx (%08lx)\n",
+ __fix_to_virt(idx), ioapic_phys);
+ idx++;
+ }
+ }
+#endif
}
-#ifndef CONFIG_SMP
-static void up_apic_timer_interrupt_call(void)
+/*
+ * This initializes the IO-APIC and APIC hardware if this is
+ * a UP kernel.
+ */
+int __init APIC_init_uniprocessor (void)
{
- int cpu = smp_processor_id();
+ if (enable_local_apic < 0)
+ clear_bit(X86_FEATURE_APIC, boot_cpu_data.x86_capability);
+
+ if (!smp_found_config && !cpu_has_apic)
+ return -1;
/*
- * the NMI deadlock-detector uses this.
+ * Complain if the BIOS pretends there is one.
*/
- per_cpu(irq_stat, cpu).apic_timer_irqs++;
+ if (!cpu_has_apic &&
+ APIC_INTEGRATED(apic_version[boot_cpu_physical_apicid])) {
+ printk(KERN_ERR "BIOS bug, local APIC #%d not detected!...\n",
+ boot_cpu_physical_apicid);
+ clear_bit(X86_FEATURE_APIC, boot_cpu_data.x86_capability);
+ return -1;
+ }
- smp_local_timer_interrupt();
-}
+ verify_local_APIC();
+
+ connect_bsp_APIC();
+
+ /*
+ * Hack: In case of kdump, after a crash, kernel might be booting
+ * on a cpu with non-zero lapic id. But boot_cpu_physical_apicid
+ * might be zero if read from MP tables. Get it from LAPIC.
+ */
+#ifdef CONFIG_CRASH_DUMP
+ boot_cpu_physical_apicid = GET_APIC_ID(apic_read(APIC_ID));
#endif
+ phys_cpu_present_map = physid_mask_of_physid(boot_cpu_physical_apicid);
-void smp_send_timer_broadcast_ipi(void)
-{
- cpumask_t mask;
+ setup_local_APIC();
- cpus_and(mask, cpu_online_map, timer_bcast_ipi);
- if (!cpus_empty(mask)) {
-#ifdef CONFIG_SMP
- send_IPI_mask(mask, LOCAL_TIMER_VECTOR);
-#else
- /*
- * We can directly call the apic timer interrupt handler
- * in UP case. Minus all irq related functions
- */
- up_apic_timer_interrupt_call();
+#ifdef CONFIG_X86_IO_APIC
+ if (smp_found_config)
+ if (!skip_ioapic_setup && nr_ioapics)
+ setup_IO_APIC();
#endif
- }
+ setup_boot_APIC_clock();
+
+ return 0;
+}
+
+/*
+ * APIC command line parameters
+ */
+static int __init parse_lapic(char *arg)
+{
+ enable_local_apic = 1;
+ return 0;
+}
+early_param("lapic", parse_lapic);
+
+static int __init parse_nolapic(char *arg)
+{
+ enable_local_apic = -1;
+ clear_bit(X86_FEATURE_APIC, boot_cpu_data.x86_capability);
+ return 0;
}
+early_param("nolapic", parse_nolapic);
-int setup_profiling_timer(unsigned int multiplier)
+static int __init apic_set_verbosity(char *str)
{
- return -EINVAL;
+ if (strcmp("debug", str) == 0)
+ apic_verbosity = APIC_DEBUG;
+ else if (strcmp("verbose", str) == 0)
+ apic_verbosity = APIC_VERBOSE;
+ return 1;
}
+__setup("apic=", apic_set_verbosity);
+
+
+/*
+ * Local APIC interrupts
+ */
+
/*
* This interrupt should _never_ happen with our APIC/SMP architecture
*/
@@ -1302,15 +1160,14 @@ fastcall void smp_spurious_interrupt(str
ack_APIC_irq();
/* see sw-dev-man vol 3, chapter 7.4.13.5 */
- printk(KERN_INFO "spurious APIC interrupt on CPU#%d, should never happen.\n",
- smp_processor_id());
+ printk(KERN_INFO "spurious APIC interrupt on CPU#%d, "
+ "should never happen.\n", smp_processor_id());
irq_exit();
}
/*
* This interrupt should never happen with our APIC/SMP architecture
*/
-
fastcall void smp_error_interrupt(struct pt_regs *regs)
{
unsigned long v, v1;
@@ -1334,69 +1191,247 @@ fastcall void smp_error_interrupt(struct
7: Illegal register address
*/
printk (KERN_DEBUG "APIC error on CPU%d: %02lx(%02lx)\n",
- smp_processor_id(), v , v1);
+ smp_processor_id(), v , v1);
irq_exit();
}
/*
- * This initializes the IO-APIC and APIC hardware if this is
- * a UP kernel.
+ * Initialize APIC interrupts
*/
-int __init APIC_init_uniprocessor (void)
+void __init apic_intr_init(void)
{
- if (enable_local_apic < 0)
- clear_bit(X86_FEATURE_APIC, boot_cpu_data.x86_capability);
+#ifdef CONFIG_SMP
+ smp_intr_init();
+#endif
+ /* self generated IPI for local APIC timer */
+ set_intr_gate(LOCAL_TIMER_VECTOR, apic_timer_interrupt);
- if (!smp_found_config && !cpu_has_apic)
- return -1;
+ /* IPI vectors for APIC spurious and error interrupts */
+ set_intr_gate(SPURIOUS_APIC_VECTOR, spurious_interrupt);
+ set_intr_gate(ERROR_APIC_VECTOR, error_interrupt);
- /*
- * Complain if the BIOS pretends there is one.
- */
- if (!cpu_has_apic && APIC_INTEGRATED(apic_version[boot_cpu_physical_apicid])) {
- printk(KERN_ERR "BIOS bug, local APIC #%d not detected!...\n",
- boot_cpu_physical_apicid);
- clear_bit(X86_FEATURE_APIC, boot_cpu_data.x86_capability);
- return -1;
+ /* thermal monitor LVT interrupt */
+#ifdef CONFIG_X86_MCE_P4THERMAL
+ set_intr_gate(THERMAL_APIC_VECTOR, thermal_interrupt);
+#endif
+}
+
+/**
+ * connect_bsp_APIC - attach the APIC to the interrupt system
+ */
+void __init connect_bsp_APIC(void)
+{
+ if (pic_mode) {
+ /*
+ * Do not trust the local APIC being empty at bootup.
+ */
+ clear_local_APIC();
+ /*
+ * PIC mode, enable APIC mode in the IMCR, i.e. connect BSP's
+ * local APIC to INT and NMI lines.
+ */
+ apic_printk(APIC_VERBOSE, "leaving PIC mode, "
+ "enabling APIC mode.\n");
+ outb(0x70, 0x22);
+ outb(0x01, 0x23);
}
+ enable_apic_mode();
+}
- verify_local_APIC();
+/**
+ * disconnect_bsp_APIC - detach the APIC from the interrupt system
+ * @virt_wire_setup: indicates, whether virtual wire mode is selected
+ *
+ * Virtual wire mode is necessary to deliver legacy interrupts even when the
+ * APIC is disabled.
+ */
+void disconnect_bsp_APIC(int virt_wire_setup)
+{
+ if (pic_mode) {
+ /*
+ * Put the board back into PIC mode (has an effect only on
+ * certain older boards). Note that APIC interrupts, including
+ * IPIs, won't work beyond this point! The only exception are
+ * INIT IPIs.
+ */
+ apic_printk(APIC_VERBOSE, "disabling APIC mode, "
+ "entering PIC mode.\n");
+ outb(0x70, 0x22);
+ outb(0x00, 0x23);
+ } else {
+ /* Go back to Virtual Wire compatibility mode */
+ unsigned long value;
- connect_bsp_APIC();
+ /* For the spurious interrupt use vector F, and enable it */
+ value = apic_read(APIC_SPIV);
+ value &= ~APIC_VECTOR_MASK;
+ value |= APIC_SPIV_APIC_ENABLED;
+ value |= 0xf;
+ apic_write_around(APIC_SPIV, value);
- /*
- * Hack: In case of kdump, after a crash, kernel might be booting
- * on a cpu with non-zero lapic id. But boot_cpu_physical_apicid
- * might be zero if read from MP tables. Get it from LAPIC.
- */
-#ifdef CONFIG_CRASH_DUMP
- boot_cpu_physical_apicid = GET_APIC_ID(apic_read(APIC_ID));
-#endif
- phys_cpu_present_map = physid_mask_of_physid(boot_cpu_physical_apicid);
+ if (!virt_wire_setup) {
+ /*
+ * For LVT0 make it edge triggered, active high,
+ * external and enabled
+ */
+ value = apic_read(APIC_LVT0);
+ value &= ~(APIC_MODE_MASK | APIC_SEND_PENDING |
+ APIC_INPUT_POLARITY | APIC_LVT_REMOTE_IRR |
+ APIC_LVT_LEVEL_TRIGGER | APIC_LVT_MASKED );
+ value |= APIC_LVT_REMOTE_IRR | APIC_SEND_PENDING;
+ value = SET_APIC_DELIVERY_MODE(value, APIC_MODE_EXTINT);
+ apic_write_around(APIC_LVT0, value);
+ } else {
+ /* Disable LVT0 */
+ apic_write_around(APIC_LVT0, APIC_LVT_MASKED);
+ }
- setup_local_APIC();
+ /*
+ * For LVT1 make it edge triggered, active high, nmi and
+ * enabled
+ */
+ value = apic_read(APIC_LVT1);
+ value &= ~(
+ APIC_MODE_MASK | APIC_SEND_PENDING |
+ APIC_INPUT_POLARITY | APIC_LVT_REMOTE_IRR |
+ APIC_LVT_LEVEL_TRIGGER | APIC_LVT_MASKED);
+ value |= APIC_LVT_REMOTE_IRR | APIC_SEND_PENDING;
+ value = SET_APIC_DELIVERY_MODE(value, APIC_MODE_NMI);
+ apic_write_around(APIC_LVT1, value);
+ }
+}
-#ifdef CONFIG_X86_IO_APIC
- if (smp_found_config)
- if (!skip_ioapic_setup && nr_ioapics)
- setup_IO_APIC();
-#endif
- setup_boot_APIC_clock();
+/*
+ * Power management
+ */
+#ifdef CONFIG_PM
+
+static struct {
+ int active;
+ /* r/w apic fields */
+ unsigned int apic_id;
+ unsigned int apic_taskpri;
+ unsigned int apic_ldr;
+ unsigned int apic_dfr;
+ unsigned int apic_spiv;
+ unsigned int apic_lvtt;
+ unsigned int apic_lvtpc;
+ unsigned int apic_lvt0;
+ unsigned int apic_lvt1;
+ unsigned int apic_lvterr;
+ unsigned int apic_tmict;
+ unsigned int apic_tdcr;
+ unsigned int apic_thmr;
+} apic_pm_state;
+
+static int lapic_suspend(struct sys_device *dev, pm_message_t state)
+{
+ unsigned long flags;
+
+ if (!apic_pm_state.active)
+ return 0;
+
+ apic_pm_state.apic_id = apic_read(APIC_ID);
+ apic_pm_state.apic_taskpri = apic_read(APIC_TASKPRI);
+ apic_pm_state.apic_ldr = apic_read(APIC_LDR);
+ apic_pm_state.apic_dfr = apic_read(APIC_DFR);
+ apic_pm_state.apic_spiv = apic_read(APIC_SPIV);
+ apic_pm_state.apic_lvtt = apic_read(APIC_LVTT);
+ apic_pm_state.apic_lvtpc = apic_read(APIC_LVTPC);
+ apic_pm_state.apic_lvt0 = apic_read(APIC_LVT0);
+ apic_pm_state.apic_lvt1 = apic_read(APIC_LVT1);
+ apic_pm_state.apic_lvterr = apic_read(APIC_LVTERR);
+ apic_pm_state.apic_tmict = apic_read(APIC_TMICT);
+ apic_pm_state.apic_tdcr = apic_read(APIC_TDCR);
+ apic_pm_state.apic_thmr = apic_read(APIC_LVTTHMR);
+ local_irq_save(flags);
+ disable_local_APIC();
+ local_irq_restore(flags);
return 0;
}
-static int __init parse_lapic(char *arg)
+static int lapic_resume(struct sys_device *dev)
{
- lapic_enable();
+ unsigned int l, h;
+ unsigned long flags;
+
+ if (!apic_pm_state.active)
+ return 0;
+
+ local_irq_save(flags);
+
+ /*
+ * Make sure the APICBASE points to the right address
+ *
+ * FIXME! This will be wrong if we ever support suspend on
+ * SMP! We'll need to do this as part of the CPU restore!
+ */
+ rdmsr(MSR_IA32_APICBASE, l, h);
+ l &= ~MSR_IA32_APICBASE_BASE;
+ l |= MSR_IA32_APICBASE_ENABLE | mp_lapic_addr;
+ wrmsr(MSR_IA32_APICBASE, l, h);
+
+ apic_write(APIC_LVTERR, ERROR_APIC_VECTOR | APIC_LVT_MASKED);
+ apic_write(APIC_ID, apic_pm_state.apic_id);
+ apic_write(APIC_DFR, apic_pm_state.apic_dfr);
+ apic_write(APIC_LDR, apic_pm_state.apic_ldr);
+ apic_write(APIC_TASKPRI, apic_pm_state.apic_taskpri);
+ apic_write(APIC_SPIV, apic_pm_state.apic_spiv);
+ apic_write(APIC_LVT0, apic_pm_state.apic_lvt0);
+ apic_write(APIC_LVT1, apic_pm_state.apic_lvt1);
+ apic_write(APIC_LVTTHMR, apic_pm_state.apic_thmr);
+ apic_write(APIC_LVTPC, apic_pm_state.apic_lvtpc);
+ apic_write(APIC_LVTT, apic_pm_state.apic_lvtt);
+ apic_write(APIC_TDCR, apic_pm_state.apic_tdcr);
+ apic_write(APIC_TMICT, apic_pm_state.apic_tmict);
+ apic_write(APIC_ESR, 0);
+ apic_read(APIC_ESR);
+ apic_write(APIC_LVTERR, apic_pm_state.apic_lvterr);
+ apic_write(APIC_ESR, 0);
+ apic_read(APIC_ESR);
+ local_irq_restore(flags);
return 0;
}
-early_param("lapic", parse_lapic);
-static int __init parse_nolapic(char *arg)
+/*
+ * This device has no shutdown method - fully functioning local APICs
+ * are needed on every CPU up until machine_halt/restart/poweroff.
+ */
+
+static struct sysdev_class lapic_sysclass = {
+ set_kset_name("lapic"),
+ .resume = lapic_resume,
+ .suspend = lapic_suspend,
+};
+
+static struct sys_device device_lapic = {
+ .id = 0,
+ .cls = &lapic_sysclass,
+};
+
+static void __devinit apic_pm_activate(void)
{
- lapic_disable();
- return 0;
+ apic_pm_state.active = 1;
}
-early_param("nolapic", parse_nolapic);
+static int __init init_lapic_sysfs(void)
+{
+ int error;
+
+ if (!cpu_has_apic)
+ return 0;
+ /* XXX: remove suspend/resume procs if !apic_pm_state.active? */
+
+ error = sysdev_class_register(&lapic_sysclass);
+ if (!error)
+ error = sysdev_register(&device_lapic);
+ return error;
+}
+device_initcall(init_lapic_sysfs);
+
+#else /* CONFIG_PM */
+
+static void apic_pm_activate(void) { }
+
+#endif /* CONFIG_PM */
Index: linux-2.6.19-rc5-mm1/arch/i386/kernel/io_apic.c
===================================================================
--- linux-2.6.19-rc5-mm1.orig/arch/i386/kernel/io_apic.c 2006-11-09 21:05:30.000000000 +0100
+++ linux-2.6.19-rc5-mm1/arch/i386/kernel/io_apic.c 2006-11-09 21:06:15.000000000 +0100
@@ -1599,7 +1599,7 @@ void /*__init*/ print_local_APIC(void *
v = apic_read(APIC_LVR);
printk(KERN_INFO "... APIC VERSION: %08x\n", v);
ver = GET_APIC_VERSION(v);
- maxlvt = get_maxlvt();
+ maxlvt = lapic_get_maxlvt();
v = apic_read(APIC_TASKPRI);
printk(KERN_DEBUG "... APIC TASKPRI: %08x (%02x)\n", v, v & APIC_TPRI_MASK);
Index: linux-2.6.19-rc5-mm1/arch/i386/kernel/irq.c
===================================================================
--- linux-2.6.19-rc5-mm1.orig/arch/i386/kernel/irq.c 2006-11-09 21:05:30.000000000 +0100
+++ linux-2.6.19-rc5-mm1/arch/i386/kernel/irq.c 2006-11-09 21:06:15.000000000 +0100
@@ -10,7 +10,6 @@
* io_apic.c.)
*/
-#include <asm/uaccess.h>
#include <linux/module.h>
#include <linux/seq_file.h>
#include <linux/interrupt.h>
@@ -19,19 +18,34 @@
#include <linux/cpu.h>
#include <linux/delay.h>
+#include <asm/apic.h>
+#include <asm/uaccess.h>
+
DEFINE_PER_CPU(irq_cpustat_t, irq_stat) ____cacheline_internodealigned_in_smp;
EXPORT_PER_CPU_SYMBOL(irq_stat);
-#ifndef CONFIG_X86_LOCAL_APIC
/*
* '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);
-}
+ printk(KERN_ERR "unexpected IRQ trap at vector %02x\n", irq);
+
+#ifdef CONFIG_X86_LOCAL_APIC
+ /*
+ * 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 only ack when the APIC is enabled -AK
+ */
+ if (cpu_has_apic)
+ ack_APIC_irq();
#endif
+}
#ifdef CONFIG_4KSTACKS
/*
Index: linux-2.6.19-rc5-mm1/arch/i386/kernel/smpboot.c
===================================================================
--- linux-2.6.19-rc5-mm1.orig/arch/i386/kernel/smpboot.c 2006-11-09 21:05:30.000000000 +0100
+++ linux-2.6.19-rc5-mm1/arch/i386/kernel/smpboot.c 2006-11-09 21:06:15.000000000 +0100
@@ -744,7 +744,7 @@ wakeup_secondary_cpu(int logical_apicid,
/*
* Due to the Pentium erratum 3AP.
*/
- maxlvt = get_maxlvt();
+ maxlvt = lapic_get_maxlvt();
if (maxlvt > 3) {
apic_read_around(APIC_SPIV);
apic_write(APIC_ESR, 0);
@@ -834,7 +834,7 @@ wakeup_secondary_cpu(int phys_apicid, un
*/
Dprintk("#startup loops: %d.\n", num_starts);
- maxlvt = get_maxlvt();
+ maxlvt = lapic_get_maxlvt();
for (j = 1; j <= num_starts; j++) {
Dprintk("Sending STARTUP #%d.\n",j);
Index: linux-2.6.19-rc5-mm1/include/asm-i386/apic.h
===================================================================
--- linux-2.6.19-rc5-mm1.orig/include/asm-i386/apic.h 2006-11-09 21:05:30.000000000 +0100
+++ linux-2.6.19-rc5-mm1/include/asm-i386/apic.h 2006-11-09 21:06:15.000000000 +0100
@@ -95,7 +95,7 @@ static inline void ack_APIC_irq(void)
extern void (*wait_timer_tick)(void);
-extern int get_maxlvt(void);
+extern int lapic_get_maxlvt(void);
extern void clear_local_APIC(void);
extern void connect_bsp_APIC (void);
extern void disconnect_bsp_APIC (int virt_wire_setup);
--
-
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