Techwizz/kernel-fxtec-pro1x
1
0
Fork 0
Code Issues Pull requests Projects Releases Packages Wiki Activity
kernel-fxtec-pro1x/arch/i386/kernel/apic.c
Zwane Mwaikambo 77f72b192f [PATCH] i386: LVT entries remaining unmasked on reboot 
Excerpt from bugzilla entry

http://bugzilla.kernel.org/show_bug.cgi?id=5518

"i386 version of Reboot-through-BIOS is unsafe: it forgets to mask APIC LVT
interrupts before jumping to a BIOS entry point.  As a result, BIOS ends up
bombarded with interrupts early on boot.  The BIOS does not expect it since
following a "normal" hardware cpu reset, all APIC LVT registers have the
Mask bit (16) set and can't generate interrupts.

For example, the version of Phoenix BIOS used by VMware enables interrupts
for the first time before masking/clearing APIC LVT.  The APIC Timer LVT
register is still set up for a timer interrupt delivery with a high vector
from the previous Linux incarnation (0xef in our case).  The BIOS has not
fully initialized its IDT at this point and the real mode gate for 0xef
remains all zeros.  Vector 0xef dispatches BIOS to address 0:0, BIOS takes
a #GP and eventually hangs.

machine_shutdown() does attempt to shut down APIC before jumping to BIOS,
but it is ineffective"

Signed-off-by: Zwane Mwaikambo <zwane@arm.linux.org.uk>
Cc: "Seth, Rohit" <rohit.seth@intel.com>
Cc: Zachary Amsden <zach@vmware.com>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-11-07 07:53:28 -08:00

1300 lines
32 KiB
C
Raw Blame History

/*
* Local APIC handling, local APIC timers
*
* (c) 1999, 2000 Ingo Molnar <mingo@redhat.com>
*
* Fixes
* Maciej W. Rozycki : Bits for genuine 82489DX APICs;
* thanks to Eric Gilmore
* and Rolf G. Tews
* for testing these extensively.
* Maciej W. Rozycki : Various updates and fixes.
* Mikael Pettersson : Power Management for UP-APIC.
* Pavel Machek and
* Mikael Pettersson : PM converted to driver model.
*/
#include <linux/config.h>
#include <linux/init.h>
#include <linux/mm.h>
#include <linux/delay.h>
#include <linux/bootmem.h>
#include <linux/smp_lock.h>
#include <linux/interrupt.h>
#include <linux/mc146818rtc.h>
#include <linux/kernel_stat.h>
#include <linux/sysdev.h>
#include <linux/cpu.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 <mach_apic.h>
#include "io_ports.h"
/*
* Knob to control our willingness to enable the local APIC.
*/
int enable_local_apic __initdata = 0; /* -1=force-disable, +1=force-enable */
/*
* Debug level
*/
int apic_verbosity;
static void apic_pm_activate(void);
/*
* 'what should we do if we get a hw irq event on an illegal vector'.
* each architecture has to answer this themselves.
*/
void ack_bad_irq(unsigned int irq)
{
printk("unexpected IRQ trap at vector %02x\n", irq);
/*
* Currently unexpected vectors happen only on SMP and APIC.
* We _must_ ack these because every local APIC has only N
* irq slots per priority level, and a 'hanging, unacked' IRQ
* holds up an irq slot - in excessive cases (when multiple
* unexpected vectors occur) that might lock up the APIC
* completely.
*/
ack_APIC_irq();
}
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
}
/* Using APIC to generate smp_local_timer_interrupt? */
int using_apic_timer = 0;
static DEFINE_PER_CPU(int, prof_multiplier) = 1;
static DEFINE_PER_CPU(int, prof_old_multiplier) = 1;
static DEFINE_PER_CPU(int, prof_counter) = 1;
static int enabled_via_apicbase;
void enable_NMI_through_LVT0 (void * dummy)
{
unsigned int v, ver;
ver = apic_read(APIC_LVR);
ver = GET_APIC_VERSION(ver);
v = APIC_DM_NMI; /* unmask and set to NMI */
if (!APIC_INTEGRATED(ver)) /* 82489DX */
v |= APIC_LVT_LEVEL_TRIGGER;
apic_write_around(APIC_LVT0, v);
}
int get_physical_broadcast(void)
{
unsigned int lvr, version;
lvr = apic_read(APIC_LVR);
version = GET_APIC_VERSION(lvr);
if (!APIC_INTEGRATED(version) || version >= 0x14)
return 0xff;
else
return 0xf;
}
int get_maxlvt(void)
{
unsigned int v, ver, maxlvt;
v = apic_read(APIC_LVR);
ver = GET_APIC_VERSION(v);
/* 82489DXs do not report # of LVT entries. */
maxlvt = APIC_INTEGRATED(ver) ? GET_APIC_MAXLVT(v) : 2;
return maxlvt;
}
void clear_local_APIC(void)
{
int maxlvt;
unsigned long v;
maxlvt = get_maxlvt();
/*
* Masking an LVT entry on a P6 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
v = GET_APIC_VERSION(apic_read(APIC_LVR));
if (APIC_INTEGRATED(v)) { /* !82489DX */
if (maxlvt > 3) /* Due to Pentium errata 3AP and 11AP. */
apic_write(APIC_ESR, 0);
apic_read(APIC_ESR);
}
}
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();
}
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);
}
}
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);
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);
}
}
/*
* 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 = 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;
}
void __init sync_Arb_IDs(void)
{
/* Unsupported on P4 - see Intel Dev. Manual Vol. 3, Ch. 8.6.1 */
unsigned int ver = GET_APIC_VERSION(apic_read(APIC_LVR));
if (ver >= 0x14) /* P4 or higher */
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);
}
extern void __error_in_apic_c (void);
/*
* An initial setup of the virtual wire mode.
*/
void __init init_bsp_APIC(void)
{
unsigned long value, ver;
/*
* 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);
ver = GET_APIC_VERSION(value);
/*
* 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 (!APIC_INTEGRATED(ver)) /* 82489DX */
value |= APIC_LVT_LEVEL_TRIGGER;
apic_write_around(APIC_LVT1, value);
}
void __devinit setup_local_APIC(void)
{
unsigned long oldvalue, value, ver, maxlvt;
/* 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);
}
value = apic_read(APIC_LVR);
ver = GET_APIC_VERSION(value);
if ((SPURIOUS_APIC_VECTOR & 0x0f) != 0x0f)
__error_in_apic_c();
/*
* 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);
/*
* 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
*/
#if 1
/* Enable focus processor (bit==0) */
value &= ~APIC_SPIV_FOCUS_DISABLED;
#else
/* Disable focus processor (bit==1) */
value |= APIC_SPIV_FOCUS_DISABLED;
#endif
/*
* 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 (!APIC_INTEGRATED(ver)) /* 82489DX */
value |= APIC_LVT_LEVEL_TRIGGER;
apic_write_around(APIC_LVT1, value);
if (APIC_INTEGRATED(ver) && !esr_disable) { /* !82489DX */
maxlvt = get_maxlvt();
if (maxlvt > 3) /* Due to the Pentium erratum 3AP. */
apic_write(APIC_ESR, 0);
oldvalue = apic_read(APIC_ESR);
value = ERROR_APIC_VECTOR; // enables sending errors
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("Leaving ESR disabled.\n");
else
printk("No ESR for 82489DX.\n");
}
if (nmi_watchdog == NMI_LOCAL_APIC)
setup_apic_nmi_watchdog();
apic_pm_activate();
}
/*
* 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)
{
if (!cpu_has_apic)
return;
local_irq_disable();
clear_local_APIC();
if (enabled_via_apicbase)
disable_local_APIC();
local_irq_enable();
}
#ifdef CONFIG_PM
static struct {
int active;
/* r/w apic fields */
unsigned int apic_id;
unsigned int apic_taskpri;
unsigned int apic_ldr;
unsigned int apic_dfr;
unsigned int apic_spiv;
unsigned int apic_lvtt;
unsigned int apic_lvtpc;
unsigned int apic_lvt0;
unsigned int apic_lvt1;
unsigned int apic_lvterr;
unsigned int apic_tmict;
unsigned int apic_tdcr;
unsigned int apic_thmr;
} apic_pm_state;
static int lapic_suspend(struct sys_device *dev, pm_message_t state)
{
unsigned long flags;
if (!apic_pm_state.active)
return 0;
apic_pm_state.apic_id = apic_read(APIC_ID);
apic_pm_state.apic_taskpri = apic_read(APIC_TASKPRI);
apic_pm_state.apic_ldr = apic_read(APIC_LDR);
apic_pm_state.apic_dfr = apic_read(APIC_DFR);
apic_pm_state.apic_spiv = apic_read(APIC_SPIV);
apic_pm_state.apic_lvtt = apic_read(APIC_LVTT);
apic_pm_state.apic_lvtpc = apic_read(APIC_LVTPC);
apic_pm_state.apic_lvt0 = apic_read(APIC_LVT0);
apic_pm_state.apic_lvt1 = apic_read(APIC_LVT1);
apic_pm_state.apic_lvterr = apic_read(APIC_LVTERR);
apic_pm_state.apic_tmict = apic_read(APIC_TMICT);
apic_pm_state.apic_tdcr = apic_read(APIC_TDCR);
apic_pm_state.apic_thmr = apic_read(APIC_LVTTHMR);
local_irq_save(flags);
disable_local_APIC();
local_irq_restore(flags);
return 0;
}
static int lapic_resume(struct sys_device *dev)
{
unsigned int l, h;
unsigned long flags;
if (!apic_pm_state.active)
return 0;
local_irq_save(flags);
/*
* Make sure the APICBASE points to the right address
*
* FIXME! This will be wrong if we ever support suspend on
* SMP! We'll need to do this as part of the CPU restore!
*/
rdmsr(MSR_IA32_APICBASE, l, h);
l &= ~MSR_IA32_APICBASE_BASE;
l |= MSR_IA32_APICBASE_ENABLE | mp_lapic_addr;
wrmsr(MSR_IA32_APICBASE, l, h);
apic_write(APIC_LVTERR, ERROR_APIC_VECTOR | APIC_LVT_MASKED);
apic_write(APIC_ID, apic_pm_state.apic_id);
apic_write(APIC_DFR, apic_pm_state.apic_dfr);
apic_write(APIC_LDR, apic_pm_state.apic_ldr);
apic_write(APIC_TASKPRI, apic_pm_state.apic_taskpri);
apic_write(APIC_SPIV, apic_pm_state.apic_spiv);
apic_write(APIC_LVT0, apic_pm_state.apic_lvt0);
apic_write(APIC_LVT1, apic_pm_state.apic_lvt1);
apic_write(APIC_LVTTHMR, apic_pm_state.apic_thmr);
apic_write(APIC_LVTPC, apic_pm_state.apic_lvtpc);
apic_write(APIC_LVTT, apic_pm_state.apic_lvtt);
apic_write(APIC_TDCR, apic_pm_state.apic_tdcr);
apic_write(APIC_TMICT, apic_pm_state.apic_tmict);
apic_write(APIC_ESR, 0);
apic_read(APIC_ESR);
apic_write(APIC_LVTERR, apic_pm_state.apic_lvterr);
apic_write(APIC_ESR, 0);
apic_read(APIC_ESR);
local_irq_restore(flags);
return 0;
}
/*
* This device has no shutdown method - fully functioning local APICs
* are needed on every CPU up until machine_halt/restart/poweroff.
*/
static struct sysdev_class lapic_sysclass = {
set_kset_name("lapic"),
.resume = lapic_resume,
.suspend = lapic_suspend,
};
static struct sys_device device_lapic = {
.id = 0,
.cls = &lapic_sysclass,
};
static void __devinit apic_pm_activate(void)
{
apic_pm_state.active = 1;
}
static int __init init_lapic_sysfs(void)
{
int error;
if (!cpu_has_apic)
return 0;
/* XXX: remove suspend/resume procs if !apic_pm_state.active? */
error = sysdev_class_register(&lapic_sysclass);
if (!error)
error = sysdev_register(&device_lapic);
return error;
}
device_initcall(init_lapic_sysfs);
#else /* CONFIG_PM */
static void apic_pm_activate(void) { }
#endif /* CONFIG_PM */
/*
* Detect and enable local APICs on non-SMP boards.
* Original code written by Keir Fraser.
*/
static int __init apic_set_verbosity(char *str)
{
if (strcmp("debug", str) == 0)
apic_verbosity = APIC_DEBUG;
else if (strcmp("verbose", str) == 0)
apic_verbosity = APIC_VERBOSE;
else
printk(KERN_WARNING "APIC Verbosity level %s not recognised"
" use apic=verbose or apic=debug", str);
return 0;
}
__setup("apic=", apic_set_verbosity);
static int __init detect_init_APIC (void)
{
u32 h, l, features;
/* Disabled by kernel option? */
if (enable_local_apic < 0)
return -1;
switch (boot_cpu_data.x86_vendor) {
case X86_VENDOR_AMD:
if ((boot_cpu_data.x86 == 6 && boot_cpu_data.x86_model > 1) ||
(boot_cpu_data.x86 == 15))
break;
goto no_apic;
case X86_VENDOR_INTEL:
if (boot_cpu_data.x86 == 6 || boot_cpu_data.x86 == 15 ||
(boot_cpu_data.x86 == 5 && cpu_has_apic))
break;
goto no_apic;
default:
goto no_apic;
}
if (!cpu_has_apic) {
/*
* Over-ride BIOS and try to enable the local
* APIC only if "lapic" specified.
*/
if (enable_local_apic <= 0) {
printk("Local APIC disabled by BIOS -- "
"you can enable it with \"lapic\"\n");
return -1;
}
/*
* Some BIOSes disable the local APIC in the
* APIC_BASE MSR. This can only be done in
* software for Intel P6 or later and AMD K7
* (Model > 1) or later.
*/
rdmsr(MSR_IA32_APICBASE, l, h);
if (!(l & MSR_IA32_APICBASE_ENABLE)) {
printk("Local APIC disabled by BIOS -- reenabling.\n");
l &= ~MSR_IA32_APICBASE_BASE;
l |= MSR_IA32_APICBASE_ENABLE | APIC_DEFAULT_PHYS_BASE;
wrmsr(MSR_IA32_APICBASE, l, h);
enabled_via_apicbase = 1;
}
}
/*
* The APIC feature bit should now be enabled
* in `cpuid'
*/
features = cpuid_edx(1);
if (!(features & (1 << X86_FEATURE_APIC))) {
printk("Could not enable APIC!\n");
return -1;
}
set_bit(X86_FEATURE_APIC, boot_cpu_data.x86_capability);
mp_lapic_addr = APIC_DEFAULT_PHYS_BASE;
/* The BIOS may have set up the APIC at some other address */
rdmsr(MSR_IA32_APICBASE, l, h);
if (l & MSR_IA32_APICBASE_ENABLE)
mp_lapic_addr = l & MSR_IA32_APICBASE_BASE;
if (nmi_watchdog != NMI_NONE)
nmi_watchdog = NMI_LOCAL_APIC;
printk("Found and enabled local APIC!\n");
apic_pm_activate();
return 0;
no_apic:
printk("No local APIC present or hardware disabled\n");
return -1;
}
void __init init_apic_mappings(void)
{
unsigned long apic_phys;
/*
* If no local APIC can be found then set up a fake all
* zeroes page to simulate the local APIC and another
* one for the IO-APIC.
*/
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 part sets up the APIC 32 bit clock in LVTT1, with HZ interrupts
* per second. We assume that the caller has already set up the local
* APIC.
*
* The APIC timer is not exactly sync with the external timer chip, it
* closely follows bus clocks.
*/
/*
* The timer chip is already set up at HZ interrupts per second here,
* but we do not accept timer interrupts yet. We only allow the BP
* to calibrate.
*/
static unsigned int __devinit get_8254_timer_count(void)
{
unsigned long flags;
unsigned int count;
spin_lock_irqsave(&i8253_lock, flags);
outb_p(0x00, PIT_MODE);
count = inb_p(PIT_CH0);
count |= inb_p(PIT_CH0) << 8;
spin_unlock_irqrestore(&i8253_lock, flags);
return count;
}
/* next tick in 8254 can be caught by catching timer wraparound */
static void __devinit wait_8254_wraparound(void)
{
unsigned int curr_count, prev_count;
curr_count = get_8254_timer_count();
do {
prev_count = curr_count;
curr_count = get_8254_timer_count();
/* workaround for broken Mercury/Neptune */
if (prev_count >= curr_count + 0x100)
curr_count = get_8254_timer_count();
} while (prev_count >= curr_count);
}
/*
* Default initialization for 8254 timers. If we use other timers like HPET,
* we override this later
*/
void (*wait_timer_tick)(void) __devinitdata = wait_8254_wraparound;
/*
* This function sets up the local APIC timer, with a timeout of
* 'clocks' APIC bus clock. During calibration we actually call
* this function twice on the boot CPU, once with a bogus timeout
* value, second time for real. The other (noncalibrating) CPUs
* call this function only once, with the real, calibrated value.
*
* We do reads before writes even if unnecessary, to get around the
* P5 APIC double write bug.
*/
#define APIC_DIVISOR 16
static void __setup_APIC_LVTT(unsigned int clocks)
{
unsigned int lvtt_value, tmp_value, ver;
ver = GET_APIC_VERSION(apic_read(APIC_LVR));
lvtt_value = APIC_LVT_TIMER_PERIODIC | LOCAL_TIMER_VECTOR;
if (!APIC_INTEGRATED(ver))
lvtt_value |= SET_APIC_TIMER_BASE(APIC_TIMER_BASE_DIV);
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);
apic_write_around(APIC_TMICT, clocks/APIC_DIVISOR);
}
static void __devinit setup_APIC_timer(unsigned int clocks)
{
unsigned long flags;
local_irq_save(flags);
/*
* Wait for IRQ0's slice:
*/
wait_timer_tick();
__setup_APIC_LVTT(clocks);
local_irq_restore(flags);
}
/*
* In this function we calibrate APIC bus clocks to the external
* timer. Unfortunately we cannot use jiffies and the timer irq
* to calibrate, since some later bootup code depends on getting
* the first irq? Ugh.
*
* We want to do the calibration only once since we
* want to have local timer irqs syncron. CPUs connected
* by the same APIC bus have the very same bus frequency.
* And we want to have irqs off anyways, no accidental
* APIC irq that way.
*/
static int __init calibrate_APIC_clock(void)
{
unsigned long long t1 = 0, t2 = 0;
long tt1, tt2;
long result;
int i;
const int LOOPS = HZ/10;
apic_printk(APIC_VERBOSE, "calibrating APIC timer ...\n");
/*
* Put whatever arbitrary (but long enough) timeout
* value into the APIC clock, we just want to get the
* counter running for calibration.
*/
__setup_APIC_LVTT(1000000000);
/*
* The timer chip counts down to zero. Let's wait
* for a wraparound to start exact measurement:
* (the current tick might have been already half done)
*/
wait_timer_tick();
/*
* We wrapped around just now. Let's start:
*/
if (cpu_has_tsc)
rdtscll(t1);
tt1 = apic_read(APIC_TMCCT);
/*
* Let's wait LOOPS wraprounds:
*/
for (i = 0; i < LOOPS; i++)
wait_timer_tick();
tt2 = apic_read(APIC_TMCCT);
if (cpu_has_tsc)
rdtscll(t2);
/*
* The APIC bus clock counter is 32 bits only, it
* might have overflown, but note that we use signed
* longs, thus no extra care needed.
*
* underflown to be exact, as the timer counts down ;)
*/
result = (tt1-tt2)*APIC_DIVISOR/LOOPS;
if (cpu_has_tsc)
apic_printk(APIC_VERBOSE, "..... CPU clock speed is "
"%ld.%04ld MHz.\n",
((long)(t2-t1)/LOOPS)/(1000000/HZ),
((long)(t2-t1)/LOOPS)%(1000000/HZ));
apic_printk(APIC_VERBOSE, "..... host bus clock speed is "
"%ld.%04ld MHz.\n",
result/(1000000/HZ),
result%(1000000/HZ));
return result;
}
static unsigned int calibration_result;
void __init setup_boot_APIC_clock(void)
{
unsigned long flags;
apic_printk(APIC_VERBOSE, "Using local APIC timer interrupts.\n");
using_apic_timer = 1;
local_irq_save(flags);
calibration_result = calibrate_APIC_clock();
/*
* Now set up the timer for real.
*/
setup_APIC_timer(calibration_result);
local_irq_restore(flags);
}
void __devinit setup_secondary_APIC_clock(void)
{
setup_APIC_timer(calibration_result);
}
void __devinit disable_APIC_timer(void)
{
if (using_apic_timer) {
unsigned long v;
v = apic_read(APIC_LVTT);
apic_write_around(APIC_LVTT, v | APIC_LVT_MASKED);
}
}
void enable_APIC_timer(void)
{
if (using_apic_timer) {
unsigned long v;
v = apic_read(APIC_LVTT);
apic_write_around(APIC_LVTT, v & ~APIC_LVT_MASKED);
}
}
/*
* the frequency of the profiling timer can be changed
* by writing a multiplier value into /proc/profile.
*/
int setup_profiling_timer(unsigned int multiplier)
{
int i;
/*
* Sanity check. [at least 500 APIC cycles should be
* between APIC interrupts as a rule of thumb, to avoid
* irqs flooding us]
*/
if ( (!multiplier) || (calibration_result/multiplier < 500))
return -EINVAL;
/*
* Set the new multiplier for each CPU. CPUs don't start using the
* new values until the next timer interrupt in which they do process
* accounting. At that time they also adjust their APIC timers
* accordingly.
*/
for (i = 0; i < NR_CPUS; ++i)
per_cpu(prof_multiplier, i) = multiplier;
return 0;
}
#undef APIC_DIVISOR
/*
* Local timer interrupt handler. It does both profiling and
* process statistics/rescheduling.
*
* We do profiling in every local tick, statistics/rescheduling
* happen only every 'profiling multiplier' ticks. The default
* multiplier is 1 and it can be changed by writing the new multiplier
* value into /proc/profile.
*/
inline void smp_local_timer_interrupt(struct pt_regs * regs)
{
int cpu = smp_processor_id();
profile_tick(CPU_PROFILING, regs);
if (--per_cpu(prof_counter, cpu) <= 0) {
/*
* The multiplier may have changed since the last time we got
* to this point as a result of the user writing to
* /proc/profile. In this case we need to adjust the APIC
* timer accordingly.
*
* Interrupts are already masked off at this point.
*/
per_cpu(prof_counter, cpu) = per_cpu(prof_multiplier, cpu);
if (per_cpu(prof_counter, cpu) !=
per_cpu(prof_old_multiplier, cpu)) {
__setup_APIC_LVTT(
calibration_result/
per_cpu(prof_counter, cpu));
per_cpu(prof_old_multiplier, cpu) =
per_cpu(prof_counter, cpu);
}
#ifdef CONFIG_SMP
update_process_times(user_mode_vm(regs));
#endif
}
/*
* We take the 'long' return path, and there every subsystem
* grabs the apropriate locks (kernel lock/ irq lock).
*
* we might want to decouple profiling from the 'long path',
* and do the profiling totally in assembly.
*
* Currently this isn't too much of an issue (performance wise),
* we can take more than 100K local irqs per second on a 100 MHz P5.
*/
}
/*
* Local APIC timer interrupt. This is the most natural way for doing
* local interrupts, but local timer interrupts can be emulated by
* broadcast interrupts too. [in case the hw doesn't support APIC timers]
*
* [ if a single-CPU system runs an SMP kernel then we call the local
* interrupt as well. Thus we cannot inline the local irq ... ]
*/
fastcall void smp_apic_timer_interrupt(struct pt_regs *regs)
{
int cpu = smp_processor_id();
/*
* the NMI deadlock-detector uses this.
*/
per_cpu(irq_stat, cpu).apic_timer_irqs++;
/*
* 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();
smp_local_timer_interrupt(regs);
irq_exit();
}
/*
* This interrupt should _never_ happen with our APIC/SMP architecture
*/
fastcall 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
*/
fastcall 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();
}
/*
* 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);
return -1;
}
verify_local_APIC();
connect_bsp_APIC();
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_APIC_clock();
return 0;
}
Reference in a new issue View git blame Copy permalink