/*
* 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/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/cpu.h>
#include <linux/clockchips.h>
#include <linux/acpi_pmtmr.h>
#include <linux/module.h>
#include <linux/dmi.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/i8253.h>
#include <asm/nmi.h>
#include <mach_apic.h>
#include <mach_apicdef.h>
#include <mach_ipi.h>
#include "io_ports.h"
/*
* Sanity check
*/
#if (SPURIOUS_APIC_VECTOR & 0x0F) != 0x0F
# error SPURIOUS_APIC_VECTOR definition error
#endif
/*
* Knob to control our willingness to enable the local APIC.
*
* -1=force-disable, +1=force-enable
*/
static int enable_local_apic __initdata = 0;
/* Local APIC timer verification ok */
static int local_apic_timer_verify_ok;
/* Disable local APIC timer from the kernel commandline or via dmi quirk */
static int local_apic_timer_disabled;
/* Local APIC timer works in C2 */
int local_apic_timer_c2_ok;
EXPORT_SYMBOL_GPL(local_apic_timer_c2_ok);
/*
* Debug level, exported for io_apic.c
*/
int apic_verbosity;
static unsigned int calibration_result;
static int lapic_next_event(unsigned long delta,
struct clock_event_device *evt);
static void lapic_timer_setup(enum clock_event_mode mode,
struct clock_event_device *evt);
static void lapic_timer_broadcast(cpumask_t mask);
static void apic_pm_activate(void);
/*
* The local apic timer can be used for any function which is CPU local.
*/
static struct clock_event_device lapic_clockevent = {
.name = "lapic",
.features = CLOCK_EVT_FEAT_PERIODIC | CLOCK_EVT_FEAT_ONESHOT
| CLOCK_EVT_FEAT_C3STOP | CLOCK_EVT_FEAT_DUMMY,
.shift = 32,
.set_mode = lapic_timer_setup,
.set_next_event = lapic_next_event,
.broadcast = lapic_timer_broadcast,
.rating = 100,
.irq = -1,
};
static DEFINE_PER_CPU(struct clock_event_device, lapic_events);
/* 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)
{
return GET_APIC_VERSION(apic_read(APIC_LVR));
}
/*
* Check, if the APIC is integrated or a seperate chip
*/
static inline int lapic_is_integrated(void)
{
return APIC_INTEGRATED(lapic_get_version());
}
/*
* Check, whether this is a modern or a first generation APIC
*/
static int modern_apic(void)
{
/* 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;
}
/**
* enable_NMI_through_LVT0 - enable NMI through local vector table 0
*/
void enable_NMI_through_LVT0 (void * dummy)
{
unsigned int v = APIC_DM_NMI;
/* 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)
{
return modern_apic() ? 0xff : 0xf;
}
/**
* lapic_get_maxlvt - get the maximum number of local vector table entries
*/
int lapic_get_maxlvt(void)
{
unsigned int v = apic_read(APIC_LVR);
/* 82489DXs do not report # of LVT entries. */
return APIC_INTEGRATED(GET_APIC_VERSION(v)) ? GET_APIC_MAXLVT(v) : 2;
}
/*
* Local APIC timer
*/
/* Clock divisor is set to 16 */
#define APIC_DIVISOR 16
/*
* 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.
*/
static void __setup_APIC_LVTT(unsigned int clocks, int oneshot, int irqen)
{
unsigned int lvtt_value, tmp_value;
lvtt_value = LOCAL_TIMER_VECTOR;
if (!oneshot)
lvtt_value |= APIC_LVT_TIMER_PERIODIC;
if (!lapic_is_integrated())
lvtt_value |= SET_APIC_TIMER_BASE(APIC_TIMER_BASE_DIV);
if (!irqen)
lvtt_value |= APIC_LVT_MASKED;
apic_write_around(APIC_LVTT, lvtt_value);
/*
* Divide PICLK by 16
*/
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 (!oneshot)
apic_write_around(APIC_TMICT, clocks/APIC_DIVISOR);
}
/*
* Program the next event, relative to now
*/
static int lapic_next_event(unsigned long delta,
struct clock_event_device *evt)
{
apic_write_around(APIC_TMICT, delta);
return 0;
}
/*
* Setup the lapic timer in periodic or oneshot mode
*/
static void lapic_timer_setup(enum clock_event_mode mode,
struct clock_event_device *evt)
{
unsigned long flags;
unsigned int v;
/* Lapic used for broadcast ? */
if (!local_apic_timer_verify_ok)
return;
local_irq_save(flags);
switch (mode) {
case CLOCK_EVT_MODE_PERIODIC:
case CLOCK_EVT_MODE_ONESHOT:
__setup_APIC_LVTT(calibration_result,
mode != CLOCK_EVT_MODE_PERIODIC, 1);
break;
case CLOCK_EVT_MODE_UNUSED:
case CLOCK_EVT_MODE_SHUTDOWN:
v = apic_read(APIC_LVTT);
v |= (APIC_LVT_MASKED | LOCAL_TIMER_VECTOR);
apic_write_around(APIC_LVTT, v);
break;
}
local_irq_restore(flags);
}
/*
* Local APIC timer broadcast function
*/
static void lapic_timer_broadcast(cpumask_t mask)
{
#ifdef CONFIG_SMP
send_IPI_mask(mask, LOCAL_TIMER_VECTOR);
#endif
}
/*
* Setup the local APIC timer for this CPU. Copy the initilized values
* of the boot CPU and register the clock event in the framework.
*/
static void __devinit setup_APIC_timer(void)
{
struct clock_event_device *levt = &__get_cpu_var(lapic_events);
memcpy(levt, &lapic_clockevent, sizeof(*levt));
levt->cpumask = cpumask_of_cpu(smp_processor_id());
clockevents_register_device(levt);
}
/*
* Detect systems with known broken BIOS implementations
*/
static int __init lapic_check_broken_bios(struct dmi_system_id *d)
{
printk(KERN_NOTICE "%s detected: disabling lapic timer.\n",
d->ident);
local_apic_timer_disabled = 1;
return 0;
}
static struct dmi_system_id __initdata broken_bios_dmi_table[] = {
{
/*
* BIOS exports only C1 state, but uses deeper power
* modes behind the kernels back.
*/
.callback = lapic_check_broken_bios,
.ident = "HP nx6325",
.matches = {
DMI_MATCH(DMI_PRODUCT_NAME, "HP Compaq nx6325"),
},
},
{}
};
/*
* In this functions we calibrate APIC bus clocks to the external timer.
*
* 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.
*
* This was previously done by reading the PIT/HPET and waiting for a wrap
* around to find out, that a tick has elapsed. I have a box, where the PIT
* readout is broken, so it never gets out of the wait loop again. This was
* also reported by others.
*
* Monitoring the jiffies value is inaccurate and the clockevents
* infrastructure allows us to do a simple substitution of the interrupt
* handler.
*
* The calibration routine also uses the pm_timer when possible, as the PIT
* happens to run way too slow (factor 2.3 on my VAIO CoreDuo, which goes
* back to normal later in the boot process).
*/
#define LAPIC_CAL_LOOPS (HZ/10)
static __initdata volatile int lapic_cal_loops = -1;
static __initdata long lapic_cal_t1, lapic_cal_t2;
static __initdata unsigned long long lapic_cal_tsc1, lapic_cal_tsc2;
static __initdata unsigned long lapic_cal_pm1, lapic_cal_pm2;
static __initdata unsigned long lapic_cal_j1, lapic_cal_j2;
/*
* Temporary interrupt handler.
*/
static void __init lapic_cal_handler(struct clock_event_device *dev)
{
unsigned long long tsc = 0;
long tapic = apic_read(APIC_TMCCT);
unsigned long pm = acpi_pm_read_early();
if (cpu_has_tsc)
rdtscll(tsc);
switch (lapic_cal_loops++) {
case 0:
lapic_cal_t1 = tapic;
lapic_cal_tsc1 = tsc;
lapic_cal_pm1 = pm;
lapic_cal_j1 = jiffies;
break;
case LAPIC_CAL_LOOPS:
lapic_cal_t2 = tapic;
lapic_cal_tsc2 = tsc;
if (pm < lapic_cal_pm1)
pm += ACPI_PM_OVRRUN;
lapic_cal_pm2 = pm;
lapic_cal_j2 = jiffies;
break;
}
}
/*
* Setup the boot APIC
*
* Calibrate and verify the result.
*/
void __init setup_boot_APIC_clock(void)
{
struct clock_event_device *levt = &__get_cpu_var(lapic_events);
const long pm_100ms = PMTMR_TICKS_PER_SEC/10;
const long pm_thresh = pm_100ms/100;
void (*real_handler)(struct clock_event_device *dev);
unsigned long deltaj;
long delta, deltapm;
int pm_referenced = 0;
/* Detect know broken systems */
dmi_check_system(broken_bios_dmi_table);
/*
* The local apic timer can be disabled via the kernel
* commandline or from the dmi quirk above. Register the lapic
* timer as a dummy clock event source on SMP systems, so the
* broadcast mechanism is used. On UP systems simply ignore it.
*/
if (local_apic_timer_disabled) {
/* No broadcast on UP ! */
if (num_possible_cpus() > 1)
setup_APIC_timer();
return;
}
apic_printk(APIC_VERBOSE, "Using local APIC timer interrupts.\n"
"calibrating APIC timer ...\n");
local_irq_disable();
/* Replace the global interrupt handler */
real_handler = global_clock_event->event_handler;
global_clock_event->event_handler = lapic_cal_handler;
/*
* Setup the APIC counter to 1e9. There is no way the lapic
* can underflow in the 100ms detection time frame
*/
__setup_APIC_LVTT(1000000000, 0, 0);
/* Let the interrupts run */
local_irq_enable();
while (lapic_cal_loops <= LAPIC_CAL_LOOPS)
cpu_relax();
local_irq_disable();
/* Restore the real event handler */
global_clock_event->event_handler = real_handler;
/* Build delta t1-t2 as apic timer counts down */
delta = lapic_cal_t1 - lapic_cal_t2;
apic_printk(APIC_VERBOSE, "... lapic delta = %ld\n", delta);
/* Check, if the PM timer is available */
deltapm = lapic_cal_pm2 - lapic_cal_pm1;
apic_printk(APIC_VERBOSE, "... PM timer delta = %ld\n", deltapm);
if (deltapm) {
unsigned long mult;
u64 res;
mult = clocksource_hz2mult(PMTMR_TICKS_PER_SEC, 22);
if (deltapm > (pm_100ms - pm_thresh) &&
deltapm < (pm_100ms + pm_thresh)) {
apic_printk(APIC_VERBOSE, "... PM timer result ok\n");
} else {
res = (((u64) deltapm) * mult) >> 22;
do_div(res, 1000000);
printk(KERN_WARNING "APIC calibration not consistent "
"with PM Timer: %ldms instead of 100ms\n",
(long)res);
/* Correct the lapic counter value */
res = (((u64) delta ) * pm_100ms);
do_div(res, deltapm);
printk(KERN_INFO "APIC delta adjusted to PM-Timer: "
"%lu (%ld)\n", (unsigned long) res, delta);
delta = (long) res;
}
pm_referenced = 1;
}
/* Calculate the scaled math multiplication factor */
lapic_clockevent.mult = div_sc(delta, TICK_NSEC * LAPIC_CAL_LOOPS, 32);
lapic_clockevent.max_delta_ns =
clockevent_delta2ns(0x7FFFFF, &lapic_clockevent);
lapic_clockevent.min_delta_ns =
clockevent_delta2ns(0xF, &lapic_clockevent);
calibration_result = (delta * APIC_DIVISOR) / LAPIC_CAL_LOOPS;
apic_printk(APIC_VERBOSE, "..... delta %ld\n", delta);
apic_printk(APIC_VERBOSE, "..... mult: %ld\n", lapic_clockevent.mult);
apic_printk(APIC_VERBOSE, "..... calibration result: %u\n",
calibration_result);
if (cpu_has_tsc) {
delta = (long)(lapic_cal_tsc2 - lapic_cal_tsc1);
apic_printk(APIC_VERBOSE, "..... CPU clock speed is "
"%ld.%04ld MHz.\n",
(delta / LAPIC_CAL_LOOPS) / (1000000 / HZ),
(delta / LAPIC_CAL_LOOPS) % (1000000 / HZ));
}
apic_printk(APIC_VERBOSE, "..... host bus clock speed is "
"%u.%04u MHz.\n",
calibration_result / (1000000 / HZ),
calibration_result % (1000000 / HZ));
local_apic_timer_verify_ok = 1;
/* We trust the pm timer based calibration */
if (!pm_referenced) {
apic_printk(APIC_VERBOSE, "... verify APIC timer\n");
/*
* Setup the apic timer manually
*/
levt->event_handler = lapic_cal_handler;
lapic_timer_setup(CLOCK_EVT_MODE_PERIODIC, levt);
lapic_cal_loops = -1;
/* Let the interrupts run */
local_irq_enable();
while(lapic_cal_loops <= LAPIC_CAL_LOOPS)
cpu_relax();
local_irq_disable();
/* Stop the lapic timer */
lapic_timer_setup(CLOCK_EVT_MODE_SHUTDOWN, levt);
local_irq_enable();
/* Jiffies delta */
deltaj = lapic_cal_j2 - lapic_cal_j1;
apic_printk(APIC_VERBOSE, "... jiffies delta = %lu\n", deltaj);
/* Check, if the jiffies result is consistent */
if (deltaj >= LAPIC_CAL_LOOPS-2 && deltaj <= LAPIC_CAL_LOOPS+2)
apic_printk(APIC_VERBOSE, "... jiffies result ok\n");
else
local_apic_timer_verify_ok = 0;
} else
local_irq_enable();
if (!local_apic_timer_verify_ok) {
printk(KERN_WARNING
"APIC timer disabled due to verification failure.\n");
/* No broadcast on UP ! */
if (num_possible_cpus() == 1)
return;
} else {
/*
* If nmi_watchdog is set to IO_APIC, we need the
* PIT/HPET going. Otherwise register lapic as a dummy
* device.
*/
if (nmi_watchdog != NMI_IO_APIC)
lapic_clockevent.features &= ~CLOCK_EVT_FEAT_DUMMY;
}
/* Setup the lapic or request the broadcast */
setup_APIC_timer();
}
void __devinit setup_secondary_APIC_clock(void)
{
setup_APIC_timer();
}
/*
* The guts of the apic timer interrupt
*/
static void local_apic_timer_interrupt(void)
{
int cpu = smp_processor_id();
struct clock_event_device *evt = &per_cpu(lapic_events, cpu);
/*
* Normally we should not be here till LAPIC has been initialized but
* in some cases like kdump, its possible that there is a pending LAPIC
* timer interrupt from previous kernel's context and is delivered in
* new kernel the moment interrupts are enabled.
*
* Interrupts are enabled early and LAPIC is setup much later, hence
* its possible that when we get here evt->event_handler is NULL.
* Check for event_handler being NULL and discard the interrupt as
* spurious.
*/
if (!evt->event_handler) {
printk(KERN_WARNING
"Spurious LAPIC timer interrupt on cpu %d\n", cpu);
/* Switch it off */
lapic_timer_setup(CLOCK_EVT_MODE_SHUTDOWN, evt);
return;
}
per_cpu(irq_stat, cpu).apic_timer_irqs++;
evt->event_handler(evt);
}
/*
* 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 fastcall smp_apic_timer_interrupt(struct pt_regs *regs)
{
struct pt_regs *old_regs = set_irq_regs(regs);
/*
* 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.
*/
irq_enter();
local_apic_timer_interrupt();
irq_exit();
set_irq_regs(old_regs);
}
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;
/*
* 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);
}
/* 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);
#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);
apic_read(APIC_ESR);
}
}
/**
* 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
* for the case where Linux didn't enable the LAPIC.
*/
void lapic_shutdown(void)
{
unsigned long flags;
if (!cpu_has_apic)
return;
local_irq_save(flags);
clear_local_APIC();
if (enabled_via_apicbase)
disable_local_APIC();
local_irq_restore(flags);
}
/*
* 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 int reg0, reg1;
/*
* 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;
/*
* Check if the version looks reasonably.
*/
reg1 = GET_APIC_VERSION(reg0);
if (reg1 == 0x00 || reg1 == 0xff)
return 0;
reg1 = lapic_get_maxlvt();
if (reg1 < 0x02 || reg1 == 0xff)
return 0;
/*
* The ID register is read/write in a real APIC.
*/
reg0 = apic_read(APIC_ID);
apic_printk(APIC_DEBUG, "Getting ID: %x\n", reg0);
/*
* 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.
*/
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);
return 1;
}
/**
* sync_Arb_IDs - synchronize APIC bus arbitration IDs
*/
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.
*/
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);
}
/*
* An initial setup of the virtual wire mode.
*/
void __init init_bsp_APIC(void)
{
unsigned long value;
/*
* 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;
/*
* Do not trust the local APIC being empty at bootup.
*/
clear_local_APIC();
/*
* 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);
/*
* 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);
}
/**
* setup_local_APIC - setup the local APIC
*/
void __devinit setup_local_APIC(void)
{
unsigned long oldvalue, value, maxlvt, integrated;
int i, j;
/* 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();
/*
* Double-check whether this APIC is really registered.
*/
if (!apic_id_registered())
BUG();
/*
* 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...
*/
init_apic_ldr();
/*
* Set Task Priority to 'accept all'. We never change this
* later on.
*/
value = apic_read(APIC_TASKPRI);
value &= ~APIC_TPRI_MASK;
apic_write_around(APIC_TASKPRI, value);
/*
* 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 = 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();
}
}
/*
* 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;
/*
* 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) */
value &= ~APIC_SPIV_FOCUS_DISABLED;
/*
* Set spurious IRQ vector
*/
value |= SPURIOUS_APIC_VECTOR;
apic_write_around(APIC_SPIV, value);
/*
* 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);
/*
* 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);
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);
/* enables sending errors */
value = ERROR_APIC_VECTOR;
apic_write_around(APIC_LVTERR, value);
/*
* spec says clear errors after enabling vector.
*/
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");
}
/* Disable the local apic timer */
value = apic_read(APIC_LVTT);
value |= (APIC_LVT_MASKED | LOCAL_TIMER_VECTOR);
apic_write_around(APIC_LVTT, value);
setup_apic_nmi_watchdog(NULL);
apic_pm_activate();
}
/*
* Detect and initialize APIC
*/
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(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;
}
}
/*
* 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;
/* 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(KERN_INFO "Found and enabled local APIC!\n");
apic_pm_activate();
return 0;
no_apic:
printk(KERN_INFO "No local APIC present or hardware disabled\n");
return -1;
}
/**
* init_apic_mappings - initialize APIC mappings
*/
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.
*/
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);
/*
* Fetch the APIC ID of the BSP in case we have a
* default configuration (or the MP table is broken).
*/
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 initializes the IO-APIC and APIC hardware if this is
* a UP kernel.
*/
int __init APIC_init_uniprocessor (void)
{
if (enable_local_apic < 0)
clear_bit(X86_FEATURE_APIC, boot_cpu_data.x86_capability);
if (!smp_found_config && !cpu_has_apic)
return -1;
/*
* 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;
}
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);
setup_local_APIC();
#ifdef CONFIG_X86_IO_APIC
if (smp_found_config)
if (!skip_ioapic_setup && nr_ioapics)
setup_IO_APIC();
#endif
setup_boot_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);
static int __init parse_disable_lapic_timer(char *arg)
{
local_apic_timer_disabled = 1;
return 0;
}
early_param("nolapic_timer", parse_disable_lapic_timer);
static int __init parse_lapic_timer_c2_ok(char *arg)
{
local_apic_timer_c2_ok = 1;
return 0;
}
early_param("lapic_timer_c2_ok", parse_lapic_timer_c2_ok);
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);
/*
* Local APIC interrupts
*/
/*
* This interrupt should _never_ happen with our APIC/SMP architecture
*/
void smp_spurious_interrupt(struct pt_regs *regs)
{
unsigned long v;
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();
/* 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());
irq_exit();
}
/*
* This interrupt should never happen with our APIC/SMP architecture
*/
void smp_error_interrupt(struct pt_regs *regs)
{
unsigned long v, v1;
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: %02lx(%02lx)\n",
smp_processor_id(), v , v1);
irq_exit();
}
/*
* Initialize APIC interrupts
*/
void __init apic_intr_init(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
}
/**
* 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();
}
/**
* 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;
/* 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);
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);
}
/*
* 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);
}
}
/*
* 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;
int maxlvt;
if (!apic_pm_state.active)
return 0;
maxlvt = lapic_get_maxlvt();
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);
if (maxlvt >= 4)
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);
#ifdef CONFIG_X86_MCE_P4THERMAL
if (maxlvt >= 5)
apic_pm_state.apic_thmr = apic_read(APIC_LVTTHMR);
#endif
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;
int maxlvt;
if (!apic_pm_state.active)
return 0;
maxlvt = lapic_get_maxlvt();
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);
#ifdef CONFIG_X86_MCE_P4THERMAL
if (maxlvt >= 5)
apic_write(APIC_LVTTHMR, apic_pm_state.apic_thmr);
#endif
if (maxlvt >= 4)
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)
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 */
