/*
* 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/interrupt.h>
#include <linux/mc146818rtc.h>
#include <linux/kernel_stat.h>
#include <linux/sysdev.h>
#include <linux/ioport.h>
#include <linux/clockchips.h>
#include <linux/acpi_pmtmr.h>
#include <linux/module.h>
#include <asm/atomic.h>
#include <asm/smp.h>
#include <asm/mtrr.h>
#include <asm/mpspec.h>
#include <asm/hpet.h>
#include <asm/pgalloc.h>
#include <asm/nmi.h>
#include <asm/idle.h>
#include <asm/proto.h>
#include <asm/timex.h>
#include <asm/apic.h>
#include <mach_ipi.h>
#include <mach_apic.h>
int disable_apic_timer __cpuinitdata;
static int apic_calibrate_pmtmr __initdata;
int disable_apic;
/* 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 struct resource lapic_resource = {
.name = "Local APIC",
.flags = IORESOURCE_MEM | IORESOURCE_BUSY,
};
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);
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);
static unsigned long apic_phys;
unsigned long mp_lapic_addr;
DEFINE_PER_CPU(u16, x86_bios_cpu_apicid) = BAD_APICID;
EXPORT_PER_CPU_SYMBOL(x86_bios_cpu_apicid);
unsigned int __cpuinitdata maxcpus = NR_CPUS;
/*
* 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 1;
}
/*
* 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;
}
void apic_wait_icr_idle(void)
{
while (apic_read(APIC_ICR) & APIC_ICR_BUSY)
cpu_relax();
}
u32 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;
udelay(100);
} while (timeout++ < 1000);
return send_status;
}
/**
* enable_NMI_through_LVT0 - enable NMI through local vector table 0
*/
void __cpuinit enable_NMI_through_LVT0(void)
{
unsigned int v;
/* unmask and set to NMI */
v = APIC_DM_NMI;
apic_write(APIC_LVT0, v);
}
/**
* lapic_get_maxlvt - get the maximum number of local vector table entries
*/
int lapic_get_maxlvt(void)
{
unsigned int v, maxlvt;
v = apic_read(APIC_LVR);
maxlvt = GET_APIC_MAXLVT(v);
return maxlvt;
}
/*
* 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 (!irqen)
lvtt_value |= APIC_LVT_MASKED;
apic_write(APIC_LVTT, lvtt_value);
/*
* 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);
}
/*
* Setup extended LVT, AMD specific (K8, family 10h)
*
* Vector mappings are hard coded. On K8 only offset 0 (APIC500) and
* MCE interrupts are supported. Thus MCE offset must be set to 0.
*/
#define APIC_EILVT_LVTOFF_MCE 0
#define APIC_EILVT_LVTOFF_IBS 1
static void setup_APIC_eilvt(u8 lvt_off, u8 vector, u8 msg_type, u8 mask)
{
unsigned long reg = (lvt_off << 4) + APIC_EILVT0;
unsigned int v = (mask << 16) | (msg_type << 8) | vector;
apic_write(reg, v);
}
u8 setup_APIC_eilvt_mce(u8 vector, u8 msg_type, u8 mask)
{
setup_APIC_eilvt(APIC_EILVT_LVTOFF_MCE, vector, msg_type, mask);
return APIC_EILVT_LVTOFF_MCE;
}
u8 setup_APIC_eilvt_ibs(u8 vector, u8 msg_type, u8 mask)
{
setup_APIC_eilvt(APIC_EILVT_LVTOFF_IBS, vector, msg_type, mask);
return APIC_EILVT_LVTOFF_IBS;
}
/*
* 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;
}
/*
* 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(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(APIC_LVTT, v);
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(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 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);
}
/*
* In this function we calibrate APIC bus clocks to the external
* timer. Unfortunately we cannot use jiffies and the timer irq
* to calibrate, since some later bootup code depends on getting
* the first irq? Ugh.
*
* We want to do the calibration only once since we
* want to have local timer irqs syncron. CPUs connected
* by the same APIC bus have the very same bus frequency.
* And we want to have irqs off anyways, no accidental
* APIC irq that way.
*/
#define TICK_COUNT 100000000
static void __init calibrate_APIC_clock(void)
{
unsigned apic, apic_start;
unsigned long tsc, tsc_start;
int result;
local_irq_disable();
/*
* Put whatever arbitrary (but long enough) timeout
* value into the APIC clock, we just want to get the
* counter running for calibration.
*
* No interrupt enable !
*/
__setup_APIC_LVTT(250000000, 0, 0);
apic_start = apic_read(APIC_TMCCT);
#ifdef CONFIG_X86_PM_TIMER
if (apic_calibrate_pmtmr && pmtmr_ioport) {
pmtimer_wait(5000); /* 5ms wait */
apic = apic_read(APIC_TMCCT);
result = (apic_start - apic) * 1000L / 5;
} else
#endif
{
rdtscll(tsc_start);
do {
apic = apic_read(APIC_TMCCT);
rdtscll(tsc);
} while ((tsc - tsc_start) < TICK_COUNT &&
(apic_start - apic) < TICK_COUNT);
result = (apic_start - apic) * 1000L * tsc_khz /
(tsc - tsc_start);
}
local_irq_enable();
printk(KERN_DEBUG "APIC timer calibration result %d\n", result);
printk(KERN_INFO "Detected %d.%03d MHz APIC timer.\n",
result / 1000 / 1000, result / 1000 % 1000);
/* Calculate the scaled math multiplication factor */
lapic_clockevent.mult = div_sc(result, NSEC_PER_SEC,
lapic_clockevent.shift);
lapic_clockevent.max_delta_ns =
clockevent_delta2ns(0x7FFFFF, &lapic_clockevent);
lapic_clockevent.min_delta_ns =
clockevent_delta2ns(0xF, &lapic_clockevent);
calibration_result = result / HZ;
}
/*
* 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.
* 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) {
printk(KERN_INFO "Disabling APIC timer\n");
/* No broadcast on UP ! */
if (num_possible_cpus() > 1) {
lapic_clockevent.mult = 1;
setup_APIC_timer();
}
return;
}
printk(KERN_INFO "Using local APIC timer interrupts.\n");
calibrate_APIC_clock();
/*
* Do a sanity check on the APIC calibration result
*/
if (calibration_result < (1000000 / HZ)) {
printk(KERN_WARNING
"APIC frequency too slow, disabling apic timer\n");
/* 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.
*/
if (nmi_watchdog != NMI_IO_APIC)
lapic_clockevent.features &= ~CLOCK_EVT_FEAT_DUMMY;
else
printk(KERN_WARNING "APIC timer registered as dummy,"
" due to nmi_watchdog=1!\n");
setup_APIC_timer();
}
/*
* AMD C1E enabled CPUs have a real nasty problem: Some BIOSes set the
* C1E flag only in the secondary CPU, so when we detect the wreckage
* we already have enabled the boot CPU local apic timer. Check, if
* disable_apic_timer is set and the DUMMY flag is cleared. If yes,
* set the DUMMY flag again and force the broadcast mode in the
* clockevents layer.
*/
static void __cpuinit check_boot_apic_timer_broadcast(void)
{
if (!disable_apic_timer ||
(lapic_clockevent.features & CLOCK_EVT_FEAT_DUMMY))
return;
printk(KERN_INFO "AMD C1E detected late. Force timer broadcast.\n");
lapic_clockevent.features |= CLOCK_EVT_FEAT_DUMMY;
local_irq_enable();
clockevents_notify(CLOCK_EVT_NOTIFY_BROADCAST_FORCE,
&boot_cpu_physical_apicid);
local_irq_disable();
}
void __cpuinit setup_secondary_APIC_clock(void)
{
check_boot_apic_timer_broadcast();
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;
}
/*
* the NMI deadlock-detector uses this.
*/
add_pda(apic_timer_irqs, 1);
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 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.
*/
exit_idle();
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();
u32 v;
/* APIC hasn't been mapped yet */
if (!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);
}
/*
* 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);
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;
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);
}
void lapic_shutdown(void)
{
unsigned long flags;
if (!cpu_has_apic)
return;
local_irq_save(flags);
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 = read_apic_id();
apic_printk(APIC_DEBUG, "Getting ID: %x\n", reg0);
apic_write(APIC_ID, reg0 ^ APIC_ID_MASK);
reg1 = read_apic_id();
apic_printk(APIC_DEBUG, "Getting ID: %x\n", reg1);
apic_write(APIC_ID, reg0);
if (reg1 != (reg0 ^ 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 */
if (modern_apic())
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;
value = apic_read(APIC_LVR);
/*
* 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;
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;
apic_write(APIC_LVT1, value);
}
/**
* setup_local_APIC - setup the local APIC
*/
void __cpuinit setup_local_APIC(void)
{
unsigned int value;
int i, j;
preempt_disable();
value = apic_read(APIC_LVR);
BUILD_BUG_ON((SPURIOUS_APIC_VECTOR & 0x0f) != 0x0f);
/*
* Double-check whether this APIC is really registered.
* This is meaningless in clustered apic mode, so we skip it.
*/
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(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;
/* We always use processor focus */
/*
* 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 (!smp_processor_id() && !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(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;
apic_write(APIC_LVT1, value);
preempt_enable();
}
static void __cpuinit lapic_setup_esr(void)
{
unsigned maxlvt = lapic_get_maxlvt();
apic_write(APIC_LVTERR, ERROR_APIC_VECTOR);
/*
* spec says clear errors after enabling vector.
*/
if (maxlvt > 3)
apic_write(APIC_ESR, 0);
}
void __cpuinit end_local_APIC_setup(void)
{
lapic_setup_esr();
nmi_watchdog_default();
setup_apic_nmi_watchdog(NULL);
apic_pm_activate();
}
/*
* 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) {
printk(KERN_INFO "No local APIC present\n");
return -1;
}
mp_lapic_addr = APIC_DEFAULT_PHYS_BASE;
boot_cpu_physical_apicid = 0;
return 0;
}
void __init early_init_lapic_mapping(void)
{
unsigned long apic_phys;
/*
* If no local APIC can be found then go out
* : it means there is no mpatable and MADT
*/
if (!smp_found_config)
return;
apic_phys = mp_lapic_addr;
set_fixmap_nocache(FIX_APIC_BASE, apic_phys);
apic_printk(APIC_VERBOSE, "mapped APIC to %16lx (%16lx)\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).
*/
boot_cpu_physical_apicid = GET_APIC_ID(read_apic_id());
}
/**
* init_apic_mappings - initialize APIC mappings
*/
void __init init_apic_mappings(void)
{
/*
* 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);
apic_printk(APIC_VERBOSE, "mapped APIC to %16lx (%16lx)\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).
*/
boot_cpu_physical_apicid = GET_APIC_ID(read_apic_id());
}
/*
* This initializes the IO-APIC and APIC hardware if this is
* a UP kernel.
*/
int __init APIC_init_uniprocessor(void)
{
if (disable_apic) {
printk(KERN_INFO "Apic disabled\n");
return -1;
}
if (!cpu_has_apic) {
disable_apic = 1;
printk(KERN_INFO "Apic disabled by BIOS\n");
return -1;
}
verify_local_APIC();
phys_cpu_present_map = physid_mask_of_physid(boot_cpu_physical_apicid);
apic_write(APIC_ID, SET_APIC_ID(boot_cpu_physical_apicid));
setup_local_APIC();
/*
* Now enable IO-APICs, actually call clear_IO_APIC
* We need clear_IO_APIC before enabling vector on BP
*/
if (!skip_ioapic_setup && nr_ioapics)
enable_IO_APIC();
end_local_APIC_setup();
if (smp_found_config && !skip_ioapic_setup && nr_ioapics)
setup_IO_APIC();
else
nr_ioapics = 0;
setup_boot_APIC_clock();
check_nmi_watchdog();
return 0;
}
/*
* Local APIC interrupts
*/
/*
* This interrupt should _never_ happen with our APIC/SMP architecture
*/
asmlinkage void smp_spurious_interrupt(void)
{
unsigned int v;
exit_idle();
irq_enter();
/*
* Check if this really is a spurious interrupt and ACK it
* if it is a vectored one. Just in case...
* Spurious interrupts should not be ACKed.
*/
v = apic_read(APIC_ISR + ((SPURIOUS_APIC_VECTOR & ~0x1f) >> 1));
if (v & (1 << (SPURIOUS_APIC_VECTOR & 0x1f)))
ack_APIC_irq();
add_pda(irq_spurious_count, 1);
irq_exit();
}
/*
* This interrupt should never happen with our APIC/SMP architecture
*/
asmlinkage void smp_error_interrupt(void)
{
unsigned int v, v1;
exit_idle();
irq_enter();
/* First tickle the hardware, only then report what went on. -- REW */
v = apic_read(APIC_ESR);
apic_write(APIC_ESR, 0);
v1 = apic_read(APIC_ESR);
ack_APIC_irq();
atomic_inc(&irq_err_count);
/* Here is what the APIC error bits mean:
0: Send CS error
1: Receive CS error
2: Send accept error
3: Receive accept error
4: Reserved
5: Send illegal vector
6: Received illegal vector
7: Illegal register address
*/
printk(KERN_DEBUG "APIC error on CPU%d: %02x(%02x)\n",
smp_processor_id(), v , v1);
irq_exit();
}
void disconnect_bsp_APIC(int virt_wire_setup)
{
/* 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(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;
cpumask_t tmp_map;
if (num_processors >= NR_CPUS) {
printk(KERN_WARNING "WARNING: NR_CPUS limit of %i reached."
" Processor ignored.\n", NR_CPUS);
return;
}
if (num_processors >= maxcpus) {
printk(KERN_WARNING "WARNING: maxcpus limit of %i reached."
" Processor ignored.\n", maxcpus);
return;
}
num_processors++;
cpus_complement(tmp_map, cpu_present_map);
cpu = first_cpu(tmp_map);
physid_set(apicid, phys_cpu_present_map);
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.
*/
cpu = 0;
}
/* are we being called early in kernel startup? */
if (x86_cpu_to_apicid_early_ptr) {
u16 *cpu_to_apicid = x86_cpu_to_apicid_early_ptr;
u16 *bios_cpu_apicid = x86_bios_cpu_apicid_early_ptr;
cpu_to_apicid[cpu] = apicid;
bios_cpu_apicid[cpu] = apicid;
} else {
per_cpu(x86_cpu_to_apicid, cpu) = apicid;
per_cpu(x86_bios_cpu_apicid, cpu) = apicid;
}
cpu_set(cpu, cpu_possible_map);
cpu_set(cpu, cpu_present_map);
}
/*
* 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(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 = 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_INTEL
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);
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_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);
local_irq_restore(flags);
return 0;
}
static struct sysdev_class lapic_sysclass = {
.name = "lapic",
.resume = lapic_resume,
.suspend = lapic_suspend,
};
static struct sys_device device_lapic = {
.id = 0,
.cls = &lapic_sysclass,
};
static void __cpuinit 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 */
/*
* 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 available data to take a good guess.
* If in doubt, go HPET.
*/
__cpuinit int apic_is_clustered_box(void)
{
int i, clusters, zeros;
unsigned id;
u16 *bios_cpu_apicid;
DECLARE_BITMAP(clustermap, NUM_APIC_CLUSTERS);
/*
* there is not this kind of box with AMD CPU yet.
* Some AMD box with quadcore cpu and 8 sockets apicid
* will be [4, 0x23] or [8, 0x27] could be thought to
* vsmp box still need checking...
*/
if ((boot_cpu_data.x86_vendor == X86_VENDOR_AMD) && !is_vsmp_box())
return 0;
bios_cpu_apicid = x86_bios_cpu_apicid_early_ptr;
bitmap_zero(clustermap, NUM_APIC_CLUSTERS);
for (i = 0; i < NR_CPUS; 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;
}
/* ScaleMP vSMPowered boxes have one cluster per board and TSCs are
* not guaranteed to be synced between boards
*/
if (is_vsmp_box() && clusters > 1)
return 1;
/*
* If clusters > 2, then should be multi-chassis.
* May have to revisit this when multi-core + hyperthreaded CPUs come
* out, but AFAIK this will work even for them.
*/
return (clusters > 2);
}
/*
* APIC command line parameters
*/
static int __init apic_set_verbosity(char *str)
{
if (str == NULL) {
skip_ioapic_setup = 0;
ioapic_force = 1;
return 0;
}
if (strcmp("debug", str) == 0)
apic_verbosity = APIC_DEBUG;
else if (strcmp("verbose", str) == 0)
apic_verbosity = APIC_VERBOSE;
else {
printk(KERN_WARNING "APIC Verbosity level %s not recognised"
" use apic=verbose or apic=debug\n", str);
return -EINVAL;
}
return 0;
}
early_param("apic", apic_set_verbosity);
static __init int setup_disableapic(char *str)
{
disable_apic = 1;
clear_cpu_cap(&boot_cpu_data, X86_FEATURE_APIC);
return 0;
}
early_param("disableapic", setup_disableapic);
/* same as disableapic, for compatibility */
static __init int setup_nolapic(char *str)
{
return setup_disableapic(str);
}
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 __init int setup_noapictimer(char *str)
{
if (str[0] != ' ' && str[0] != 0)
return 0;
disable_apic_timer = 1;
return 1;
}
__setup("noapictimer", setup_noapictimer);
static __init int setup_apicpmtimer(char *s)
{
apic_calibrate_pmtmr = 1;
notsc_setup(NULL);
return 0;
}
__setup("apicpmtimer", setup_apicpmtimer);
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);
