/*
* Local APIC handling, local APIC timers
*
* (c) 1999, 2000, 2009 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/perf_event.h>
#include <linux/kernel_stat.h>
#include <linux/mc146818rtc.h>
#include <linux/acpi_pmtmr.h>
#include <linux/clockchips.h>
#include <linux/interrupt.h>
#include <linux/bootmem.h>
#include <linux/ftrace.h>
#include <linux/ioport.h>
#include <linux/module.h>
#include <linux/syscore_ops.h>
#include <linux/delay.h>
#include <linux/timex.h>
#include <linux/i8253.h>
#include <linux/dmar.h>
#include <linux/init.h>
#include <linux/cpu.h>
#include <linux/dmi.h>
#include <linux/smp.h>
#include <linux/mm.h>
#include <asm/irq_remapping.h>
#include <asm/perf_event.h>
#include <asm/x86_init.h>
#include <asm/pgalloc.h>
#include <linux/atomic.h>
#include <asm/mpspec.h>
#include <asm/i8259.h>
#include <asm/proto.h>
#include <asm/apic.h>
#include <asm/io_apic.h>
#include <asm/desc.h>
#include <asm/hpet.h>
#include <asm/idle.h>
#include <asm/mtrr.h>
#include <asm/time.h>
#include <asm/smp.h>
#include <asm/mce.h>
#include <asm/tsc.h>
#include <asm/hypervisor.h>
unsigned int num_processors;
unsigned disabled_cpus __cpuinitdata;
/* Processor that is doing the boot up */
unsigned int boot_cpu_physical_apicid = -1U;
/*
* The highest APIC ID seen during enumeration.
*/
unsigned int max_physical_apicid;
/*
* Bitmask of physically existing CPUs:
*/
physid_mask_t phys_cpu_present_map;
/*
* Map cpu index to physical APIC ID
*/
DEFINE_EARLY_PER_CPU_READ_MOSTLY(u16, x86_cpu_to_apicid, BAD_APICID);
DEFINE_EARLY_PER_CPU_READ_MOSTLY(u16, x86_bios_cpu_apicid, BAD_APICID);
EXPORT_EARLY_PER_CPU_SYMBOL(x86_cpu_to_apicid);
EXPORT_EARLY_PER_CPU_SYMBOL(x86_bios_cpu_apicid);
#ifdef CONFIG_X86_32
/*
* On x86_32, the mapping between cpu and logical apicid may vary
* depending on apic in use. The following early percpu variable is
* used for the mapping. This is where the behaviors of x86_64 and 32
* actually diverge. Let's keep it ugly for now.
*/
DEFINE_EARLY_PER_CPU_READ_MOSTLY(int, x86_cpu_to_logical_apicid, BAD_APICID);
/* Local APIC was disabled by the BIOS and enabled by the kernel */
static int enabled_via_apicbase;
/*
* Handle interrupt mode configuration register (IMCR).
* This register controls whether the interrupt signals
* that reach the BSP come from the master PIC or from the
* local APIC. Before entering Symmetric I/O Mode, either
* the BIOS or the operating system must switch out of
* PIC Mode by changing the IMCR.
*/
static inline void imcr_pic_to_apic(void)
{
/* select IMCR register */
outb(0x70, 0x22);
/* NMI and 8259 INTR go through APIC */
outb(0x01, 0x23);
}
static inline void imcr_apic_to_pic(void)
{
/* select IMCR register */
outb(0x70, 0x22);
/* NMI and 8259 INTR go directly to BSP */
outb(0x00, 0x23);
}
#endif
/*
* Knob to control our willingness to enable the local APIC.
*
* +1=force-enable
*/
static int force_enable_local_apic __initdata;
/*
* APIC command line parameters
*/
static int __init parse_lapic(char *arg)
{
if (config_enabled(CONFIG_X86_32) && !arg)
force_enable_local_apic = 1;
else if (arg && !strncmp(arg, "notscdeadline", 13))
setup_clear_cpu_cap(X86_FEATURE_TSC_DEADLINE_TIMER);
return 0;
}
early_param("lapic", parse_lapic);
#ifdef CONFIG_X86_64
static int apic_calibrate_pmtmr __initdata;
static __init int setup_apicpmtimer(char *s)
{
apic_calibrate_pmtmr = 1;
notsc_setup(NULL);
return 0;
}
__setup("apicpmtimer", setup_apicpmtimer);
#endif
int x2apic_mode;
#ifdef CONFIG_X86_X2APIC
/* x2apic enabled before OS handover */
int x2apic_preenabled;
static int x2apic_disabled;
static int nox2apic;
static __init int setup_nox2apic(char *str)
{
if (x2apic_enabled()) {
int apicid = native_apic_msr_read(APIC_ID);
if (apicid >= 255) {
pr_warning("Apicid: %08x, cannot enforce nox2apic\n",
apicid);
return 0;
}
pr_warning("x2apic already enabled. will disable it\n");
} else
setup_clear_cpu_cap(X86_FEATURE_X2APIC);
nox2apic = 1;
return 0;
}
early_param("nox2apic", setup_nox2apic);
#endif
unsigned long mp_lapic_addr;
int disable_apic;
/* Disable local APIC timer from the kernel commandline or via dmi quirk */
static int disable_apic_timer __initdata;
/* Local APIC timer works in C2 */
int local_apic_timer_c2_ok;
EXPORT_SYMBOL_GPL(local_apic_timer_c2_ok);
int first_system_vector = 0xfe;
/*
* Debug level, exported for io_apic.c
*/
unsigned int apic_verbosity;
int pic_mode;
/* Have we found an MP table */
int smp_found_config;
static struct resource lapic_resource = {
.name = "Local APIC",
.flags = IORESOURCE_MEM | IORESOURCE_BUSY,
};
unsigned int lapic_timer_frequency = 0;
static void apic_pm_activate(void);
static unsigned long apic_phys;
/*
* 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 separate chip
*/
static inline int lapic_is_integrated(void)
{
#ifdef CONFIG_X86_64
return 1;
#else
return APIC_INTEGRATED(lapic_get_version());
#endif
}
/*
* 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;
}
/*
* right after this call apic become NOOP driven
* so apic->write/read doesn't do anything
*/
static void __init apic_disable(void)
{
pr_info("APIC: switched to apic NOOP\n");
apic = &apic_noop;
}
void native_apic_wait_icr_idle(void)
{
while (apic_read(APIC_ICR) & APIC_ICR_BUSY)
cpu_relax();
}
u32 native_safe_apic_wait_icr_idle(void)
{
u32 send_status;
int timeout;
timeout = 0;
do {
send_status = apic_read(APIC_ICR) & APIC_ICR_BUSY;
if (!send_status)
break;
inc_irq_stat(icr_read_retry_count);
udelay(100);
} while (timeout++ < 1000);
return send_status;
}
void native_apic_icr_write(u32 low, u32 id)
{
apic_write(APIC_ICR2, SET_APIC_DEST_FIELD(id));
apic_write(APIC_ICR, low);
}
u64 native_apic_icr_read(void)
{
u32 icr1, icr2;
icr2 = apic_read(APIC_ICR2);
icr1 = apic_read(APIC_ICR);
return icr1 | ((u64)icr2 << 32);
}
#ifdef CONFIG_X86_32
/**
* get_physical_broadcast - Get number of physical broadcast IDs
*/
int get_physical_broadcast(void)
{
return modern_apic() ? 0xff : 0xf;
}
#endif
/**
* lapic_get_maxlvt - get the maximum number of local vector table entries
*/
int lapic_get_maxlvt(void)
{
unsigned int v;
v = apic_read(APIC_LVR);
/*
* - we always have APIC integrated on 64bit mode
* - 82489DXs do not report # of LVT entries
*/
return APIC_INTEGRATED(GET_APIC_VERSION(v)) ? GET_APIC_MAXLVT(v) : 2;
}
/*
* Local APIC timer
*/
/* Clock divisor */
#define APIC_DIVISOR 16
#define TSC_DIVISOR 32
/*
* 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;
else if (boot_cpu_has(X86_FEATURE_TSC_DEADLINE_TIMER))
lvtt_value |= APIC_LVT_TIMER_TSCDEADLINE;
if (!lapic_is_integrated())
lvtt_value |= SET_APIC_TIMER_BASE(APIC_TIMER_BASE_DIV);
if (!irqen)
lvtt_value |= APIC_LVT_MASKED;
apic_write(APIC_LVTT, lvtt_value);
if (lvtt_value & APIC_LVT_TIMER_TSCDEADLINE) {
printk_once(KERN_DEBUG "TSC deadline timer enabled\n");
return;
}
/*
* Divide PICLK by 16
*/
tmp_value = apic_read(APIC_TDCR);
apic_write(APIC_TDCR,
(tmp_value & ~(APIC_TDR_DIV_1 | APIC_TDR_DIV_TMBASE)) |
APIC_TDR_DIV_16);
if (!oneshot)
apic_write(APIC_TMICT, clocks / APIC_DIVISOR);
}
/*
* Setup extended LVT, AMD specific
*
* Software should use the LVT offsets the BIOS provides. The offsets
* are determined by the subsystems using it like those for MCE
* threshold or IBS. On K8 only offset 0 (APIC500) and MCE interrupts
* are supported. Beginning with family 10h at least 4 offsets are
* available.
*
* Since the offsets must be consistent for all cores, we keep track
* of the LVT offsets in software and reserve the offset for the same
* vector also to be used on other cores. An offset is freed by
* setting the entry to APIC_EILVT_MASKED.
*
* If the BIOS is right, there should be no conflicts. Otherwise a
* "[Firmware Bug]: ..." error message is generated. However, if
* software does not properly determines the offsets, it is not
* necessarily a BIOS bug.
*/
static atomic_t eilvt_offsets[APIC_EILVT_NR_MAX];
static inline int eilvt_entry_is_changeable(unsigned int old, unsigned int new)
{
return (old & APIC_EILVT_MASKED)
|| (new == APIC_EILVT_MASKED)
|| ((new & ~APIC_EILVT_MASKED) == old);
}
static unsigned int reserve_eilvt_offset(int offset, unsigned int new)
{
unsigned int rsvd, vector;
if (offset >= APIC_EILVT_NR_MAX)
return ~0;
rsvd = atomic_read(&eilvt_offsets[offset]);
do {
vector = rsvd & ~APIC_EILVT_MASKED; /* 0: unassigned */
if (vector && !eilvt_entry_is_changeable(vector, new))
/* may not change if vectors are different */
return rsvd;
rsvd = atomic_cmpxchg(&eilvt_offsets[offset], rsvd, new);
} while (rsvd != new);
rsvd &= ~APIC_EILVT_MASKED;
if (rsvd && rsvd != vector)
pr_info("LVT offset %d assigned for vector 0x%02x\n",
offset, rsvd);
return new;
}
/*
* If mask=1, the LVT entry does not generate interrupts while mask=0
* enables the vector. See also the BKDGs. Must be called with
* preemption disabled.
*/
int setup_APIC_eilvt(u8 offset, u8 vector, u8 msg_type, u8 mask)
{
unsigned long reg = APIC_EILVTn(offset);
unsigned int new, old, reserved;
new = (mask << 16) | (msg_type << 8) | vector;
old = apic_read(reg);
reserved = reserve_eilvt_offset(offset, new);
if (reserved != new) {
pr_err(FW_BUG "cpu %d, try to use APIC%lX (LVT offset %d) for "
"vector 0x%x, but the register is already in use for "
"vector 0x%x on another cpu\n",
smp_processor_id(), reg, offset, new, reserved);
return -EINVAL;
}
if (!eilvt_entry_is_changeable(old, new)) {
pr_err(FW_BUG "cpu %d, try to use APIC%lX (LVT offset %d) for "
"vector 0x%x, but the register is already in use for "
"vector 0x%x on this cpu\n",
smp_processor_id(), reg, offset, new, old);
return -EBUSY;
}
apic_write(reg, new);
return 0;
}
EXPORT_SYMBOL_GPL(setup_APIC_eilvt);
/*
* Program the next event, relative to now
*/
static int lapic_next_event(unsigned long delta,
struct clock_event_device *evt)
{
apic_write(APIC_TMICT, delta);
return 0;
}
static int lapic_next_deadline(unsigned long delta,
struct clock_event_device *evt)
{
u64 tsc;
rdtscll(tsc);
wrmsrl(MSR_IA32_TSC_DEADLINE, tsc + (((u64) delta) * TSC_DIVISOR));
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 as dummy for broadcast ? */
if (evt->features & CLOCK_EVT_FEAT_DUMMY)
return;
local_irq_save(flags);
switch (mode) {
case CLOCK_EVT_MODE_PERIODIC:
case CLOCK_EVT_MODE_ONESHOT:
__setup_APIC_LVTT(lapic_timer_frequency,
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(APIC_LVTT, v);
apic_write(APIC_TMICT, 0);
break;
case CLOCK_EVT_MODE_RESUME:
/* Nothing to do here */
break;
}
local_irq_restore(flags);
}
/*
* Local APIC timer broadcast function
*/
static void lapic_timer_broadcast(const struct cpumask *mask)
{
#ifdef CONFIG_SMP
apic->send_IPI_mask(mask, LOCAL_TIMER_VECTOR);
#endif
}
/*
* 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);
/*
* Setup the local APIC timer for this CPU. Copy the initialized values
* of the boot CPU and register the clock event in the framework.
*/
static void __cpuinit setup_APIC_timer(void)
{
struct clock_event_device *levt = &__get_cpu_var(lapic_events);
if (this_cpu_has(X86_FEATURE_ARAT)) {
lapic_clockevent.features &= ~CLOCK_EVT_FEAT_C3STOP;
/* Make LAPIC timer preferrable over percpu HPET */
lapic_clockevent.rating = 150;
}
memcpy(levt, &lapic_clockevent, sizeof(*levt));
levt->cpumask = cpumask_of(smp_processor_id());
if (this_cpu_has(X86_FEATURE_TSC_DEADLINE_TIMER)) {
levt->features &= ~(CLOCK_EVT_FEAT_PERIODIC |
CLOCK_EVT_FEAT_DUMMY);
levt->set_next_event = lapic_next_deadline;
clockevents_config_and_register(levt,
(tsc_khz / TSC_DIVISOR) * 1000,
0xF, ~0UL);
} else
clockevents_register_device(levt);
}
/*
* 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 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;
}
}
static int __init
calibrate_by_pmtimer(long deltapm, long *delta, long *deltatsc)
{
const long pm_100ms = PMTMR_TICKS_PER_SEC / 10;
const long pm_thresh = pm_100ms / 100;
unsigned long mult;
u64 res;
#ifndef CONFIG_X86_PM_TIMER
return -1;
#endif
apic_printk(APIC_VERBOSE, "... PM-Timer delta = %ld\n", deltapm);
/* Check, if the PM timer is available */
if (!deltapm)
return -1;
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");
return 0;
}
res = (((u64)deltapm) * mult) >> 22;
do_div(res, 1000000);
pr_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);
pr_info("APIC delta adjusted to PM-Timer: "
"%lu (%ld)\n", (unsigned long)res, *delta);
*delta = (long)res;
/* Correct the tsc counter value */
if (cpu_has_tsc) {
res = (((u64)(*deltatsc)) * pm_100ms);
do_div(res, deltapm);
apic_printk(APIC_VERBOSE, "TSC delta adjusted to "
"PM-Timer: %lu (%ld)\n",
(unsigned long)res, *deltatsc);
*deltatsc = (long)res;
}
return 0;
}
static int __init calibrate_APIC_clock(void)
{
struct clock_event_device *levt = &__get_cpu_var(lapic_events);
void (*real_handler)(struct clock_event_device *dev);
unsigned long deltaj;
long delta, deltatsc;
int pm_referenced = 0;
/**
* check if lapic timer has already been calibrated by platform
* specific routine, such as tsc calibration code. if so, we just fill
* in the clockevent structure and return.
*/
if (boot_cpu_has(X86_FEATURE_TSC_DEADLINE_TIMER)) {
return 0;
} else if (lapic_timer_frequency) {
apic_printk(APIC_VERBOSE, "lapic timer already calibrated %d\n",
lapic_timer_frequency);
lapic_clockevent.mult = div_sc(lapic_timer_frequency/APIC_DIVISOR,
TICK_NSEC, lapic_clockevent.shift);
lapic_clockevent.max_delta_ns =
clockevent_delta2ns(0x7FFFFF, &lapic_clockevent);
lapic_clockevent.min_delta_ns =
clockevent_delta2ns(0xF, &lapic_clockevent);
lapic_clockevent.features &= ~CLOCK_EVT_FEAT_DUMMY;
return 0;
}
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 maximum. There is no way the lapic
* can underflow in the 100ms detection time frame
*/
__setup_APIC_LVTT(0xffffffff, 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);
deltatsc = (long)(lapic_cal_tsc2 - lapic_cal_tsc1);
/* we trust the PM based calibration if possible */
pm_referenced = !calibrate_by_pmtimer(lapic_cal_pm2 - lapic_cal_pm1,
&delta, &deltatsc);
/* Calculate the scaled math multiplication factor */
lapic_clockevent.mult = div_sc(delta, TICK_NSEC * LAPIC_CAL_LOOPS,
lapic_clockevent.shift);
lapic_clockevent.max_delta_ns =
clockevent_delta2ns(0x7FFFFFFF, &lapic_clockevent);
lapic_clockevent.min_delta_ns =
clockevent_delta2ns(0xF, &lapic_clockevent);
lapic_timer_frequency = (delta * APIC_DIVISOR) / LAPIC_CAL_LOOPS;
apic_printk(APIC_VERBOSE, "..... delta %ld\n", delta);
apic_printk(APIC_VERBOSE, "..... mult: %u\n", lapic_clockevent.mult);
apic_printk(APIC_VERBOSE, "..... calibration result: %u\n",
lapic_timer_frequency);
if (cpu_has_tsc) {
apic_printk(APIC_VERBOSE, "..... CPU clock speed is "
"%ld.%04ld MHz.\n",
(deltatsc / LAPIC_CAL_LOOPS) / (1000000 / HZ),
(deltatsc / LAPIC_CAL_LOOPS) % (1000000 / HZ));
}
apic_printk(APIC_VERBOSE, "..... host bus clock speed is "
"%u.%04u MHz.\n",
lapic_timer_frequency / (1000000 / HZ),
lapic_timer_frequency % (1000000 / HZ));
/*
* Do a sanity check on the APIC calibration result
*/
if (lapic_timer_frequency < (1000000 / HZ)) {
local_irq_enable();
pr_warning("APIC frequency too slow, disabling apic timer\n");
return -1;
}
levt->features &= ~CLOCK_EVT_FEAT_DUMMY;
/*
* PM timer calibration failed or not turned on
* so lets try APIC 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();
/* Stop the lapic timer */
lapic_timer_setup(CLOCK_EVT_MODE_SHUTDOWN, levt);
/* 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
levt->features |= CLOCK_EVT_FEAT_DUMMY;
} else
local_irq_enable();
if (levt->features & CLOCK_EVT_FEAT_DUMMY) {
pr_warning("APIC timer disabled due to verification failure\n");
return -1;
}
return 0;
}
/*
* Setup the boot APIC
*
* Calibrate and verify the result.
*/
void __init setup_boot_APIC_clock(void)
{
/*
* The local apic timer can be disabled via the kernel
* commandline or from the CPU detection code. 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 (disable_apic_timer) {
pr_info("Disabling APIC timer\n");
/* No broadcast on UP ! */
if (num_possible_cpus() > 1) {
lapic_clockevent.mult = 1;
setup_APIC_timer();
}
return;
}
if (calibrate_APIC_clock()) {
/* No broadcast on UP ! */
if (num_possible_cpus() > 1)
setup_APIC_timer();
return;
}
/*
* If nmi_watchdog is set to IO_APIC, we need the
* PIT/HPET going. Otherwise register lapic as a dummy
* device.
*/
lapic_clockevent.features &= ~CLOCK_EVT_FEAT_DUMMY;
/* Setup the lapic or request the broadcast */
setup_APIC_timer();
}
void __cpuinit 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) {
pr_warning("Spurious LAPIC timer interrupt on cpu %d\n", cpu);
/* Switch it off */
lapic_timer_setup(CLOCK_EVT_MODE_SHUTDOWN, evt);
return;
}
/*
* the NMI deadlock-detector uses this.
*/
inc_irq_stat(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 __irq_entry 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();
exit_idle();
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;
u32 v;
/* APIC hasn't been mapped yet */
if (!x2apic_mode && !apic_phys)
return;
maxlvt = lapic_get_maxlvt();
/*
* 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(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(APIC_LVTT, v | APIC_LVT_MASKED);
v = apic_read(APIC_LVT0);
apic_write(APIC_LVT0, v | APIC_LVT_MASKED);
v = apic_read(APIC_LVT1);
apic_write(APIC_LVT1, v | APIC_LVT_MASKED);
if (maxlvt >= 4) {
v = apic_read(APIC_LVTPC);
apic_write(APIC_LVTPC, v | APIC_LVT_MASKED);
}
/* lets not touch this if we didn't frob it */
#ifdef CONFIG_X86_THERMAL_VECTOR
if (maxlvt >= 5) {
v = apic_read(APIC_LVTTHMR);
apic_write(APIC_LVTTHMR, v | APIC_LVT_MASKED);
}
#endif
#ifdef CONFIG_X86_MCE_INTEL
if (maxlvt >= 6) {
v = apic_read(APIC_LVTCMCI);
if (!(v & APIC_LVT_MASKED))
apic_write(APIC_LVTCMCI, v | APIC_LVT_MASKED);
}
#endif
/*
* Clean APIC state for other OSs:
*/
apic_write(APIC_LVTT, APIC_LVT_MASKED);
apic_write(APIC_LVT0, APIC_LVT_MASKED);
apic_write(APIC_LVT1, APIC_LVT_MASKED);
if (maxlvt >= 3)
apic_write(APIC_LVTERR, APIC_LVT_MASKED);
if (maxlvt >= 4)
apic_write(APIC_LVTPC, APIC_LVT_MASKED);
/* 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 int value;
/* APIC hasn't been mapped yet */
if (!x2apic_mode && !apic_phys)
return;
clear_local_APIC();
/*
* Disable APIC (implies clearing of registers
* for 82489DX!).
*/
value = apic_read(APIC_SPIV);
value &= ~APIC_SPIV_APIC_ENABLED;
apic_write(APIC_SPIV, value);
#ifdef CONFIG_X86_32
/*
* 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);
}
#endif
}
/*
* 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 && !apic_from_smp_config())
return;
local_irq_save(flags);
#ifdef CONFIG_X86_32
if (!enabled_via_apicbase)
clear_local_APIC();
else
#endif
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);
apic_write(APIC_ID, reg0 ^ apic->apic_id_mask);
reg1 = apic_read(APIC_ID);
apic_printk(APIC_DEBUG, "Getting ID: %x\n", reg1);
apic_write(APIC_ID, reg0);
if (reg1 != (reg0 ^ apic->apic_id_mask))
return 0;
/*
* 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() || boot_cpu_data.x86_vendor == X86_VENDOR_AMD)
return;
/*
* Wait for idle.
*/
apic_wait_icr_idle();
apic_printk(APIC_DEBUG, "Synchronizing Arb IDs.\n");
apic_write(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 int 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;
#ifdef CONFIG_X86_32
/* 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
#endif
value |= APIC_SPIV_FOCUS_DISABLED;
value |= SPURIOUS_APIC_VECTOR;
apic_write(APIC_SPIV, value);
/*
* Set up the virtual wire mode.
*/
apic_write(APIC_LVT0, APIC_DM_EXTINT);
value = APIC_DM_NMI;
if (!lapic_is_integrated()) /* 82489DX */
value |= APIC_LVT_LEVEL_TRIGGER;
apic_write(APIC_LVT1, value);
}
static void __cpuinit lapic_setup_esr(void)
{
unsigned int oldvalue, value, maxlvt;
if (!lapic_is_integrated()) {
pr_info("No ESR for 82489DX.\n");
return;
}
if (apic->disable_esr) {
/*
* Something untraceable 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
*/
pr_info("Leaving ESR disabled.\n");
return;
}
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(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%08x after: 0x%08x\n",
oldvalue, value);
}
/**
* setup_local_APIC - setup the local APIC
*
* Used to setup local APIC while initializing BSP or bringin up APs.
* Always called with preemption disabled.
*/
void __cpuinit setup_local_APIC(void)
{
int cpu = smp_processor_id();
unsigned int value, queued;
int i, j, acked = 0;
unsigned long long tsc = 0, ntsc;
long long max_loops = cpu_khz;
if (cpu_has_tsc)
rdtscll(tsc);
if (disable_apic) {
disable_ioapic_support();
return;
}
#ifdef CONFIG_X86_32
/* Pound the ESR really hard over the head with a big hammer - mbligh */
if (lapic_is_integrated() && apic->disable_esr) {
apic_write(APIC_ESR, 0);
apic_write(APIC_ESR, 0);
apic_write(APIC_ESR, 0);
apic_write(APIC_ESR, 0);
}
#endif
perf_events_lapic_init();
/*
* Double-check whether this APIC is really registered.
* This is meaningless in clustered apic mode, so we skip it.
*/
BUG_ON(!apic->apic_id_registered());
/*
* 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...
*/
apic->init_apic_ldr();
#ifdef CONFIG_X86_32
/*
* APIC LDR is initialized. If logical_apicid mapping was
* initialized during get_smp_config(), make sure it matches the
* actual value.
*/
i = early_per_cpu(x86_cpu_to_logical_apicid, cpu);
WARN_ON(i != BAD_APICID && i != logical_smp_processor_id());
/* always use the value from LDR */
early_per_cpu(x86_cpu_to_logical_apicid, cpu) =
logical_smp_processor_id();
/*
* Some NUMA implementations (NUMAQ) don't initialize apicid to
* node mapping during NUMA init. Now that logical apicid is
* guaranteed to be known, give it another chance. This is already
* a bit too late - percpu allocation has already happened without
* proper NUMA affinity.
*/
if (apic->x86_32_numa_cpu_node)
set_apicid_to_node(early_per_cpu(x86_cpu_to_apicid, cpu),
apic->x86_32_numa_cpu_node(cpu));
#endif
/*
* Set Task Priority to 'accept all'. We never change this
* later on.
*/
value = apic_read(APIC_TASKPRI);
value &= ~APIC_TPRI_MASK;
apic_write(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.
*/
do {
queued = 0;
for (i = APIC_ISR_NR - 1; i >= 0; i--)
queued |= apic_read(APIC_IRR + i*0x10);
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();
acked++;
}
}
}
if (acked > 256) {
printk(KERN_ERR "LAPIC pending interrupts after %d EOI\n",
acked);
break;
}
if (queued) {
if (cpu_has_tsc) {
rdtscll(ntsc);
max_loops = (cpu_khz << 10) - (ntsc - tsc);
} else
max_loops--;
}
} while (queued && max_loops > 0);
WARN_ON(max_loops <= 0);
/*
* 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;
#ifdef CONFIG_X86_32
/*
* Some unknown Intel IO/APIC (or APIC) errata is biting us with
* certain networking cards. If high frequency interrupts are
* happening on a particular IOAPIC pin, plus the IOAPIC routing
* entry is masked/unmasked at a high rate as well then sooner or
* later IOAPIC line gets 'stuck', no more interrupts are received
* from the device. If focus CPU is disabled then the hang goes
* away, oh well :-(
*
* [ This bug can be reproduced easily with a level-triggered
* PCI Ne2000 networking cards and PII/PIII processors, dual
* BX chipset. ]
*/
/*
* Actually disabling the focus CPU check just makes the hang less
* frequent as it makes the interrupt distributon model be more
* like LRU than MRU (the short-term load is more even across CPUs).
* See also the comment in end_level_ioapic_irq(). --macro
*/
/*
* - enable focus processor (bit==0)
* - 64bit mode always use processor focus
* so no need to set it
*/
value &= ~APIC_SPIV_FOCUS_DISABLED;
#endif
/*
* Set spurious IRQ vector
*/
value |= SPURIOUS_APIC_VECTOR;
apic_write(APIC_SPIV, value);
/*
* Set up LVT0, LVT1:
*
* set up through-local-APIC on the BP's LINT0. This is not
* strictly necessary 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 (!cpu && (pic_mode || !value)) {
value = APIC_DM_EXTINT;
apic_printk(APIC_VERBOSE, "enabled ExtINT on CPU#%d\n", cpu);
} else {
value = APIC_DM_EXTINT | APIC_LVT_MASKED;
apic_printk(APIC_VERBOSE, "masked ExtINT on CPU#%d\n", cpu);
}
apic_write(APIC_LVT0, value);
/*
* only the BP should see the LINT1 NMI signal, obviously.
*/
if (!cpu)
value = APIC_DM_NMI;
else
value = APIC_DM_NMI | APIC_LVT_MASKED;
if (!lapic_is_integrated()) /* 82489DX */
value |= APIC_LVT_LEVEL_TRIGGER;
apic_write(APIC_LVT1, value);
#ifdef CONFIG_X86_MCE_INTEL
/* Recheck CMCI information after local APIC is up on CPU #0 */
if (!cpu)
cmci_recheck();
#endif
}
void __cpuinit end_local_APIC_setup(void)
{
lapic_setup_esr();
#ifdef CONFIG_X86_32
{
unsigned int value;
/* Disable the local apic timer */
value = apic_read(APIC_LVTT);
value |= (APIC_LVT_MASKED | LOCAL_TIMER_VECTOR);
apic_write(APIC_LVTT, value);
}
#endif
apic_pm_activate();
}
void __init bsp_end_local_APIC_setup(void)
{
end_local_APIC_setup();
/*
* Now that local APIC setup is completed for BP, configure the fault
* handling for interrupt remapping.
*/
irq_remap_enable_fault_handling();
}
#ifdef CONFIG_X86_X2APIC
/*
* Need to disable xapic and x2apic at the same time and then enable xapic mode
*/
static inline void __disable_x2apic(u64 msr)
{
wrmsrl(MSR_IA32_APICBASE,
msr & ~(X2APIC_ENABLE | XAPIC_ENABLE));
wrmsrl(MSR_IA32_APICBASE, msr & ~X2APIC_ENABLE);
}
static __init void disable_x2apic(void)
{
u64 msr;
if (!cpu_has_x2apic)
return;
rdmsrl(MSR_IA32_APICBASE, msr);
if (msr & X2APIC_ENABLE) {
u32 x2apic_id = read_apic_id();
if (x2apic_id >= 255)
panic("Cannot disable x2apic, id: %08x\n", x2apic_id);
pr_info("Disabling x2apic\n");
__disable_x2apic(msr);
if (nox2apic) {
clear_cpu_cap(&cpu_data(0), X86_FEATURE_X2APIC);
setup_clear_cpu_cap(X86_FEATURE_X2APIC);
}
x2apic_disabled = 1;
x2apic_mode = 0;
register_lapic_address(mp_lapic_addr);
}
}
void check_x2apic(void)
{
if (x2apic_enabled()) {
pr_info("x2apic enabled by BIOS, switching to x2apic ops\n");
x2apic_preenabled = x2apic_mode = 1;
}
}
void enable_x2apic(void)
{
u64 msr;
rdmsrl(MSR_IA32_APICBASE, msr);
if (x2apic_disabled) {
__disable_x2apic(msr);
return;
}
if (!x2apic_mode)
return;
if (!(msr & X2APIC_ENABLE)) {
printk_once(KERN_INFO "Enabling x2apic\n");
wrmsrl(MSR_IA32_APICBASE, msr | X2APIC_ENABLE);
}
}
#endif /* CONFIG_X86_X2APIC */
int __init enable_IR(void)
{
#ifdef CONFIG_IRQ_REMAP
if (!irq_remapping_supported()) {
pr_debug("intr-remapping not supported\n");
return -1;
}
if (!x2apic_preenabled && skip_ioapic_setup) {
pr_info("Skipped enabling intr-remap because of skipping "
"io-apic setup\n");
return -1;
}
return irq_remapping_enable();
#endif
return -1;
}
void __init enable_IR_x2apic(void)
{
unsigned long flags;
int ret, x2apic_enabled = 0;
int hardware_init_ret;
/* Make sure irq_remap_ops are initialized */
setup_irq_remapping_ops();
hardware_init_ret = irq_remapping_prepare();
if (hardware_init_ret && !x2apic_supported())
return;
ret = save_ioapic_entries();
if (ret) {
pr_info("Saving IO-APIC state failed: %d\n", ret);
return;
}
local_irq_save(flags);
legacy_pic->mask_all();
mask_ioapic_entries();
if (x2apic_preenabled && nox2apic)
disable_x2apic();
if (hardware_init_ret)
ret = -1;
else
ret = enable_IR();
if (!x2apic_supported())
goto skip_x2apic;
if (ret < 0) {
/* IR is required if there is APIC ID > 255 even when running
* under KVM
*/
if (max_physical_apicid > 255 ||
!hypervisor_x2apic_available()) {
if (x2apic_preenabled)
disable_x2apic();
goto skip_x2apic;
}
/*
* without IR all CPUs can be addressed by IOAPIC/MSI
* only in physical mode
*/
x2apic_force_phys();
}
if (ret == IRQ_REMAP_XAPIC_MODE) {
pr_info("x2apic not enabled, IRQ remapping is in xapic mode\n");
goto skip_x2apic;
}
x2apic_enabled = 1;
if (x2apic_supported() && !x2apic_mode) {
x2apic_mode = 1;
enable_x2apic();
pr_info("Enabled x2apic\n");
}
skip_x2apic:
if (ret < 0) /* IR enabling failed */
restore_ioapic_entries();
legacy_pic->restore_mask();
local_irq_restore(flags);
}
#ifdef CONFIG_X86_64
/*
* Detect and enable local APICs on non-SMP boards.
* Original code written by Keir Fraser.
* On AMD64 we trust the BIOS - if it says no APIC it is likely
* not correctly set up (usually the APIC timer won't work etc.)
*/
static int __init detect_init_APIC(void)
{
if (!cpu_has_apic) {
pr_info("No local APIC present\n");
return -1;
}
mp_lapic_addr = APIC_DEFAULT_PHYS_BASE;
return 0;
}
#else
static int __init apic_verify(void)
{
u32 features, h, l;
/*
* The APIC feature bit should now be enabled
* in `cpuid'
*/
features = cpuid_edx(1);
if (!(features & (1 << X86_FEATURE_APIC))) {
pr_warning("Could not enable APIC!\n");
return -1;
}
set_cpu_cap(&boot_cpu_data, X86_FEATURE_APIC);
mp_lapic_addr = APIC_DEFAULT_PHYS_BASE;
/* The BIOS may have set up the APIC at some other address */
if (boot_cpu_data.x86 >= 6) {
rdmsr(MSR_IA32_APICBASE, l, h);
if (l & MSR_IA32_APICBASE_ENABLE)
mp_lapic_addr = l & MSR_IA32_APICBASE_BASE;
}
pr_info("Found and enabled local APIC!\n");
return 0;
}
int __init apic_force_enable(unsigned long addr)
{
u32 h, l;
if (disable_apic)
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.
*/
if (boot_cpu_data.x86 >= 6) {
rdmsr(MSR_IA32_APICBASE, l, h);
if (!(l & MSR_IA32_APICBASE_ENABLE)) {
pr_info("Local APIC disabled by BIOS -- reenabling.\n");
l &= ~MSR_IA32_APICBASE_BASE;
l |= MSR_IA32_APICBASE_ENABLE | addr;
wrmsr(MSR_IA32_APICBASE, l, h);
enabled_via_apicbase = 1;
}
}
return apic_verify();
}
/*
* Detect and initialize APIC
*/
static int __init detect_init_APIC(void)
{
/* Disabled by kernel option? */
if (disable_apic)
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 (!force_enable_local_apic) {
pr_info("Local APIC disabled by BIOS -- "
"you can enable it with \"lapic\"\n");
return -1;
}
if (apic_force_enable(APIC_DEFAULT_PHYS_BASE))
return -1;
} else {
if (apic_verify())
return -1;
}
apic_pm_activate();
return 0;
no_apic:
pr_info("No local APIC present or hardware disabled\n");
return -1;
}
#endif
/**
* init_apic_mappings - initialize APIC mappings
*/
void __init init_apic_mappings(void)
{
unsigned int new_apicid;
if (x2apic_mode) {
boot_cpu_physical_apicid = read_apic_id();
return;
}
/* If no local APIC can be found return early */
if (!smp_found_config && detect_init_APIC()) {
/* lets NOP'ify apic operations */
pr_info("APIC: disable apic facility\n");
apic_disable();
} else {
apic_phys = mp_lapic_addr;
/*
* acpi lapic path already maps that address in
* acpi_register_lapic_address()
*/
if (!acpi_lapic && !smp_found_config)
register_lapic_address(apic_phys);
}
/*
* Fetch the APIC ID of the BSP in case we have a
* default configuration (or the MP table is broken).
*/
new_apicid = read_apic_id();
if (boot_cpu_physical_apicid != new_apicid) {
boot_cpu_physical_apicid = new_apicid;
/*
* yeah -- we lie about apic_version
* in case if apic was disabled via boot option
* but it's not a problem for SMP compiled kernel
* since smp_sanity_check is prepared for such a case
* and disable smp mode
*/
apic_version[new_apicid] =
GET_APIC_VERSION(apic_read(APIC_LVR));
}
}
void __init register_lapic_address(unsigned long address)
{
mp_lapic_addr = address;
if (!x2apic_mode) {
set_fixmap_nocache(FIX_APIC_BASE, address);
apic_printk(APIC_VERBOSE, "mapped APIC to %16lx (%16lx)\n",
APIC_BASE, mp_lapic_addr);
}
if (boot_cpu_physical_apicid == -1U) {
boot_cpu_physical_apicid = read_apic_id();
apic_version[boot_cpu_physical_apicid] =
GET_APIC_VERSION(apic_read(APIC_LVR));
}
}
/*
* This initializes the IO-APIC and APIC hardware if this is
* a UP kernel.
*/
int apic_version[MAX_LOCAL_APIC];
int __init APIC_init_uniprocessor(void)
{
if (disable_apic) {
pr_info("Apic disabled\n");
return -1;
}
#ifdef CONFIG_X86_64
if (!cpu_has_apic) {
disable_apic = 1;
pr_info("Apic disabled by BIOS\n");
return -1;
}
#else
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])) {
pr_err("BIOS bug, local APIC 0x%x not detected!...\n",
boot_cpu_physical_apicid);
return -1;
}
#endif
default_setup_apic_routing();
verify_local_APIC();
connect_bsp_APIC();
#ifdef CONFIG_X86_64
apic_write(APIC_ID, SET_APIC_ID(boot_cpu_physical_apicid));
#else
/*
* 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 = read_apic_id();
# endif
#endif
physid_set_mask_of_physid(boot_cpu_physical_apicid, &phys_cpu_present_map);
setup_local_APIC();
#ifdef CONFIG_X86_IO_APIC
/*
* Now enable IO-APICs, actually call clear_IO_APIC
* We need clear_IO_APIC before enabling error vector
*/
if (!skip_ioapic_setup && nr_ioapics)
enable_IO_APIC();
#endif
bsp_end_local_APIC_setup();
#ifdef CONFIG_X86_IO_APIC
if (smp_found_config && !skip_ioapic_setup && nr_ioapics)
setup_IO_APIC();
else {
nr_ioapics = 0;
}
#endif
x86_init.timers.setup_percpu_clockev();
return 0;
}
/*
* Local APIC interrupts
*/
/*
* This interrupt should _never_ happen with our APIC/SMP architecture
*/
void smp_spurious_interrupt(struct pt_regs *regs)
{
u32 v;
irq_enter();
exit_idle();
/*
* 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();
inc_irq_stat(irq_spurious_count);
/* see sw-dev-man vol 3, chapter 7.4.13.5 */
pr_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)
{
u32 v0, v1;
u32 i = 0;
static const char * const error_interrupt_reason[] = {
"Send CS error", /* APIC Error Bit 0 */
"Receive CS error", /* APIC Error Bit 1 */
"Send accept error", /* APIC Error Bit 2 */
"Receive accept error", /* APIC Error Bit 3 */
"Redirectable IPI", /* APIC Error Bit 4 */
"Send illegal vector", /* APIC Error Bit 5 */
"Received illegal vector", /* APIC Error Bit 6 */
"Illegal register address", /* APIC Error Bit 7 */
};
irq_enter();
exit_idle();
/* First tickle the hardware, only then report what went on. -- REW */
v0 = apic_read(APIC_ESR);
apic_write(APIC_ESR, 0);
v1 = apic_read(APIC_ESR);
ack_APIC_irq();
atomic_inc(&irq_err_count);
apic_printk(APIC_DEBUG, KERN_DEBUG "APIC error on CPU%d: %02x(%02x)",
smp_processor_id(), v0 , v1);
v1 = v1 & 0xff;
while (v1) {
if (v1 & 0x1)
apic_printk(APIC_DEBUG, KERN_CONT " : %s", error_interrupt_reason[i]);
i++;
v1 >>= 1;
}
apic_printk(APIC_DEBUG, KERN_CONT "\n");
irq_exit();
}
/**
* connect_bsp_APIC - attach the APIC to the interrupt system
*/
void __init connect_bsp_APIC(void)
{
#ifdef CONFIG_X86_32
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");
imcr_pic_to_apic();
}
#endif
if (apic->enable_apic_mode)
apic->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)
{
unsigned int value;
#ifdef CONFIG_X86_32
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");
imcr_apic_to_pic();
return;
}
#endif
/* Go back to Virtual Wire compatibility mode */
/* 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(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(APIC_LVT0, value);
} else {
/* Disable LVT0 */
apic_write(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(APIC_LVT1, value);
}
void __cpuinit generic_processor_info(int apicid, int version)
{
int cpu, max = nr_cpu_ids;
bool boot_cpu_detected = physid_isset(boot_cpu_physical_apicid,
phys_cpu_present_map);
/*
* If boot cpu has not been detected yet, then only allow upto
* nr_cpu_ids - 1 processors and keep one slot free for boot cpu
*/
if (!boot_cpu_detected && num_processors >= nr_cpu_ids - 1 &&
apicid != boot_cpu_physical_apicid) {
int thiscpu = max + disabled_cpus - 1;
pr_warning(
"ACPI: NR_CPUS/possible_cpus limit of %i almost"
" reached. Keeping one slot for boot cpu."
" Processor %d/0x%x ignored.\n", max, thiscpu, apicid);
disabled_cpus++;
return;
}
if (num_processors >= nr_cpu_ids) {
int thiscpu = max + disabled_cpus;
pr_warning(
"ACPI: NR_CPUS/possible_cpus limit of %i reached."
" Processor %d/0x%x ignored.\n", max, thiscpu, apicid);
disabled_cpus++;
return;
}
num_processors++;
if (apicid == boot_cpu_physical_apicid) {
/*
* x86_bios_cpu_apicid is required to have processors listed
* in same order as logical cpu numbers. Hence the first
* entry is BSP, and so on.
* boot_cpu_init() already hold bit 0 in cpu_present_mask
* for BSP.
*/
cpu = 0;
} else
cpu = cpumask_next_zero(-1, cpu_present_mask);
/*
* Validate version
*/
if (version == 0x0) {
pr_warning("BIOS bug: APIC version is 0 for CPU %d/0x%x, fixing up to 0x10\n",
cpu, apicid);
version = 0x10;
}
apic_version[apicid] = version;
if (version != apic_version[boot_cpu_physical_apicid]) {
pr_warning("BIOS bug: APIC version mismatch, boot CPU: %x, CPU %d: version %x\n",
apic_version[boot_cpu_physical_apicid], cpu, version);
}
physid_set(apicid, phys_cpu_present_map);
if (apicid > max_physical_apicid)
max_physical_apicid = apicid;
#if defined(CONFIG_SMP) || defined(CONFIG_X86_64)
early_per_cpu(x86_cpu_to_apicid, cpu) = apicid;
early_per_cpu(x86_bios_cpu_apicid, cpu) = apicid;
#endif
#ifdef CONFIG_X86_32
early_per_cpu(x86_cpu_to_logical_apicid, cpu) =
apic->x86_32_early_logical_apicid(cpu);
#endif
set_cpu_possible(cpu, true);
set_cpu_present(cpu, true);
}
int hard_smp_processor_id(void)
{
return read_apic_id();
}
void default_init_apic_ldr(void)
{
unsigned long val;
apic_write(APIC_DFR, APIC_DFR_VALUE);
val = apic_read(APIC_LDR) & ~APIC_LDR_MASK;
val |= SET_APIC_LOGICAL_ID(1UL << smp_processor_id());
apic_write(APIC_LDR, val);
}
int default_cpu_mask_to_apicid_and(const struct cpumask *cpumask,
const struct cpumask *andmask,
unsigned int *apicid)
{
unsigned int cpu;
for_each_cpu_and(cpu, cpumask, andmask) {
if (cpumask_test_cpu(cpu, cpu_online_mask))
break;
}
if (likely(cpu < nr_cpu_ids)) {
*apicid = per_cpu(x86_cpu_to_apicid, cpu);
return 0;
}
return -EINVAL;
}
/*
* Override the generic EOI implementation with an optimized version.
* Only called during early boot when only one CPU is active and with
* interrupts disabled, so we know this does not race with actual APIC driver
* use.
*/
void __init apic_set_eoi_write(void (*eoi_write)(u32 reg, u32 v))
{
struct apic **drv;
for (drv = __apicdrivers; drv < __apicdrivers_end; drv++) {
/* Should happen once for each apic */
WARN_ON((*drv)->eoi_write == eoi_write);
(*drv)->eoi_write = eoi_write;
}
}
/*
* Power management
*/
#ifdef CONFIG_PM
static struct {
/*
* 'active' is true if the local APIC was enabled by us and
* not the BIOS; this signifies that we are also responsible
* for disabling it before entering apm/acpi suspend
*/
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(void)
{
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_THERMAL_VECTOR
if (maxlvt >= 5)
apic_pm_state.apic_thmr = apic_read(APIC_LVTTHMR);
#endif
local_irq_save(flags);
disable_local_APIC();
irq_remapping_disable();
local_irq_restore(flags);
return 0;
}
static void lapic_resume(void)
{
unsigned int l, h;
unsigned long flags;
int maxlvt;
if (!apic_pm_state.active)
return;
local_irq_save(flags);
/*
* IO-APIC and PIC have their own resume routines.
* We just mask them here to make sure the interrupt
* subsystem is completely quiet while we enable x2apic
* and interrupt-remapping.
*/
mask_ioapic_entries();
legacy_pic->mask_all();
if (x2apic_mode)
enable_x2apic();
else {
/*
* 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!
*/
if (boot_cpu_data.x86 >= 6) {
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);
}
}
maxlvt = lapic_get_maxlvt();
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);
#if defined(CONFIG_X86_MCE_P4THERMAL) || defined(CONFIG_X86_MCE_INTEL)
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);
irq_remapping_reenable(x2apic_mode);
local_irq_restore(flags);
}
/*
* This device has no shutdown method - fully functioning local APICs
* are needed on every CPU up until machine_halt/restart/poweroff.
*/
static struct syscore_ops lapic_syscore_ops = {
.resume = lapic_resume,
.suspend = lapic_suspend,
};
static void __cpuinit apic_pm_activate(void)
{
apic_pm_state.active = 1;
}
static int __init init_lapic_sysfs(void)
{
/* XXX: remove suspend/resume procs if !apic_pm_state.active? */
if (cpu_has_apic)
register_syscore_ops(&lapic_syscore_ops);
return 0;
}
/* local apic needs to resume before other devices access its registers. */
core_initcall(init_lapic_sysfs);
#else /* CONFIG_PM */
static void apic_pm_activate(void) { }
#endif /* CONFIG_PM */
#ifdef CONFIG_X86_64
static int __cpuinit apic_cluster_num(void)
{
int i, clusters, zeros;
unsigned id;
u16 *bios_cpu_apicid;
DECLARE_BITMAP(clustermap, NUM_APIC_CLUSTERS);
bios_cpu_apicid = early_per_cpu_ptr(x86_bios_cpu_apicid);
bitmap_zero(clustermap, NUM_APIC_CLUSTERS);
for (i = 0; i < nr_cpu_ids; i++) {
/* are we being called early in kernel startup? */
if (bios_cpu_apicid) {
id = bios_cpu_apicid[i];
} else if (i < nr_cpu_ids) {
if (cpu_present(i))
id = per_cpu(x86_bios_cpu_apicid, i);
else
continue;
} else
break;
if (id != BAD_APICID)
__set_bit(APIC_CLUSTERID(id), clustermap);
}
/* Problem: Partially populated chassis may not have CPUs in some of
* the APIC clusters they have been allocated. Only present CPUs have
* x86_bios_cpu_apicid entries, thus causing zeroes in the bitmap.
* Since clusters are allocated sequentially, count zeros only if
* they are bounded by ones.
*/
clusters = 0;
zeros = 0;
for (i = 0; i < NUM_APIC_CLUSTERS; i++) {
if (test_bit(i, clustermap)) {
clusters += 1 + zeros;
zeros = 0;
} else
++zeros;
}
return clusters;
}
static int __cpuinitdata multi_checked;
static int __cpuinitdata multi;
static int __cpuinit set_multi(const struct dmi_system_id *d)
{
if (multi)
return 0;
pr_info("APIC: %s detected, Multi Chassis\n", d->ident);
multi = 1;
return 0;
}
static const __cpuinitconst struct dmi_system_id multi_dmi_table[] = {
{
.callback = set_multi,
.ident = "IBM System Summit2",
.matches = {
DMI_MATCH(DMI_SYS_VENDOR, "IBM"),
DMI_MATCH(DMI_PRODUCT_NAME, "Summit2"),
},
},
{}
};
static void __cpuinit dmi_check_multi(void)
{
if (multi_checked)
return;
dmi_check_system(multi_dmi_table);
multi_checked = 1;
}
/*
* apic_is_clustered_box() -- Check if we can expect good TSC
*
* Thus far, the major user of this is IBM's Summit2 series:
* Clustered boxes may have unsynced TSC problems if they are
* multi-chassis.
* Use DMI to check them
*/
__cpuinit int apic_is_clustered_box(void)
{
dmi_check_multi();
if (multi)
return 1;
if (!is_vsmp_box())
return 0;
/*
* ScaleMP vSMPowered boxes have one cluster per board and TSCs are
* not guaranteed to be synced between boards
*/
if (apic_cluster_num() > 1)
return 1;
return 0;
}
#endif
/*
* APIC command line parameters
*/
static int __init setup_disableapic(char *arg)
{
disable_apic = 1;
setup_clear_cpu_cap(X86_FEATURE_APIC);
return 0;
}
early_param("disableapic", setup_disableapic);
/* same as disableapic, for compatibility */
static int __init setup_nolapic(char *arg)
{
return setup_disableapic(arg);
}
early_param("nolapic", setup_nolapic);
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 parse_disable_apic_timer(char *arg)
{
disable_apic_timer = 1;
return 0;
}
early_param("noapictimer", parse_disable_apic_timer);
static int __init parse_nolapic_timer(char *arg)
{
disable_apic_timer = 1;
return 0;
}
early_param("nolapic_timer", parse_nolapic_timer);
static int __init apic_set_verbosity(char *arg)
{
if (!arg) {
#ifdef CONFIG_X86_64
skip_ioapic_setup = 0;
return 0;
#endif
return -EINVAL;
}
if (strcmp("debug", arg) == 0)
apic_verbosity = APIC_DEBUG;
else if (strcmp("verbose", arg) == 0)
apic_verbosity = APIC_VERBOSE;
else {
pr_warning("APIC Verbosity level %s not recognised"
" use apic=verbose or apic=debug\n", arg);
return -EINVAL;
}
return 0;
}
early_param("apic", apic_set_verbosity);
static int __init lapic_insert_resource(void)
{
if (!apic_phys)
return -1;
/* Put local APIC into the resource map. */
lapic_resource.start = apic_phys;
lapic_resource.end = lapic_resource.start + PAGE_SIZE - 1;
insert_resource(&iomem_resource, &lapic_resource);
return 0;
}
/*
* need call insert after e820_reserve_resources()
* that is using request_resource
*/
late_initcall(lapic_insert_resource);