apic.c

linux-2.6.15.6

	 * 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
}

/*