Commit f2b36db6 authored by Eric W. Biederman's avatar Eric W. Biederman Committed by Linus Torvalds
Browse files

[PATCH] i386: move apic init in init_IRQs 



All kinds of ugliness exists because we don't initialize
the apics during init_IRQs.
- We calibrate jiffies in non apic mode even when we are using apics.
- We have to have special code to initialize the apics when non-smp.
- The legacy i8259 must exist and be setup correctly, even
  when we won't use it past initialization.
- The kexec on panic code must restore the state of the io_apics.
- init/main.c needs a special case for !smp smp_init on x86

In addition to pure code movement I needed a couple
of non-obvious changes:
- Move setup_boot_APIC_clock into APIC_late_time_init for
  simplicity.
- Use cpu_khz to generate a better approximation of loops_per_jiffies
  so I can verify the timer interrupt is working.
- Call setup_apic_nmi_watchdog again after cpu_khz is initialized on
  the boot cpu.

Signed-off-by: default avatarEric W. Biederman <ebiederm@xmission.com>
Signed-off-by: default avatarAndrew Morton <akpm@osdl.org>
Signed-off-by: default avatarLinus Torvalds <torvalds@osdl.org>
parent 29b70081

arch/i386/kernel/apic.c

+64 −17
Original line number Diff line number Diff line
@@ -803,6 +803,7 @@ no_apic: 


void __init init_apic_mappings(void)

{

	unsigned int orig_apicid;

	unsigned long apic_phys;



	/*
@@ -824,8 +825,11 @@ void __init init_apic_mappings(void) 
	 * 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)

	orig_apicid = boot_cpu_physical_apicid;

	boot_cpu_physical_apicid = GET_APIC_ID(apic_read(APIC_ID));

	if ((orig_apicid != -1U) && (orig_apicid != boot_cpu_physical_apicid))

		printk(KERN_WARNING "Boot APIC ID in local APIC unexpected (%d vs %d)",

			orig_apicid, boot_cpu_physical_apicid);



#ifdef CONFIG_X86_IO_APIC

	{
@@ -1046,9 +1050,11 @@ 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);

	local_irq_disable();



	calibration_result = calibrate_APIC_clock();
@@ -1057,7 +1063,7 @@ void __init setup_boot_APIC_clock(void) 
	 */

	setup_APIC_timer(calibration_result);



	local_irq_enable();

	local_irq_restore(flags);

}



void __devinit setup_secondary_APIC_clock(void)
@@ -1254,40 +1260,81 @@ fastcall void smp_error_interrupt(struct pt_regs *regs) 
}



/*

 * This initializes the IO-APIC and APIC hardware if this is

 * a UP kernel.

 * This initializes the IO-APIC and APIC hardware.

 */

int __init APIC_init_uniprocessor (void)

int __init APIC_init(void)

{

	if (enable_local_apic < 0)

		clear_bit(X86_FEATURE_APIC, boot_cpu_data.x86_capability);

	if (enable_local_apic < 0) {

		printk(KERN_INFO "APIC disabled\n");

		return -1;

	}



	if (!smp_found_config && !cpu_has_apic)

	/* See if we have a SMP configuration or have forced enabled

	 * the local apic.

	 */

	if (!smp_found_config && !acpi_lapic && !cpu_has_apic) {

		enable_local_apic = -1;

		return -1;

	}



	/*

	 * Complain if the BIOS pretends there is one.

	 * Complain if the BIOS pretends there is an apic.

	 * Then get out because we don't have an a local apic.

	 */

	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);

		printk(KERN_ERR "... forcing use of dummy APIC emulation. (tell your hw vendor)\n");

		enable_local_apic = -1;

		return -1;

	}



	verify_local_APIC();



	connect_bsp_APIC();



	phys_cpu_present_map = physid_mask_of_physid(boot_cpu_physical_apicid);

	/*

	 * Should not be necessary because the MP table should list the boot

	 * CPU too, but we do it for the sake of robustness anyway.

	 * Makes no sense to do this check in clustered apic mode, so skip it

	 */

	if (!check_phys_apicid_present(boot_cpu_physical_apicid)) {

		printk("weird, boot CPU (#%d) not listed by the BIOS.\n",

				boot_cpu_physical_apicid);

		physid_set(hard_smp_processor_id(), phys_cpu_present_map);

	}



	/*

	 * Switch from PIC to APIC mode.

	 */

	connect_bsp_APIC();

	setup_local_APIC();



#ifdef CONFIG_X86_IO_APIC

	if (smp_found_config)

		if (!skip_ioapic_setup && nr_ioapics)

	/*

	 * Now start the IO-APICs

	 */

	if (smp_found_config && !skip_ioapic_setup && nr_ioapics)

		setup_IO_APIC();

#endif

	setup_boot_APIC_clock();



	return 0;

}



void __init APIC_late_time_init(void)

{

	/* Improve our loops per jiffy estimate */

	loops_per_jiffy = ((1000 + HZ - 1)/HZ)*cpu_khz;

	boot_cpu_data.loops_per_jiffy = loops_per_jiffy;

	cpu_data[0].loops_per_jiffy = loops_per_jiffy;



	/* setup_apic_nmi_watchdog doesn't work properly before cpu_khz is

	 * initialized.  So redo it here to ensure the boot cpu is setup

	 * properly.

	 */

	if (nmi_watchdog == NMI_LOCAL_APIC)

		setup_apic_nmi_watchdog();



#ifdef CONFIG_X86_IO_APIC

	if (smp_found_config && !skip_ioapic_setup && nr_ioapics)

		IO_APIC_late_time_init();

#endif

	setup_boot_APIC_clock();

}

arch/i386/kernel/i8259.c

+4 −0
Original line number Diff line number Diff line
@@ -435,4 +435,8 @@ void __init init_IRQ(void) 
		setup_irq(FPU_IRQ, &fpu_irq);



	irq_ctx_init(smp_processor_id());



#ifdef CONFIG_X86_LOCAL_APIC

	APIC_init();

#endif

}

arch/i386/kernel/io_apic.c

+5 −1
Original line number Diff line number Diff line
@@ -2387,11 +2387,15 @@ void __init setup_IO_APIC(void) 
	sync_Arb_IDs();

	setup_IO_APIC_irqs();

	init_IO_APIC_traps();

	check_timer();

	if (!acpi_ioapic)

		print_IO_APIC();

}



void __init IO_APIC_late_time_init(void)

{

	check_timer();

}



/*

 *	Called after all the initialization is done. If we didnt find any

 *	APIC bugs then we can allow the modify fast path

arch/i386/kernel/smpboot.c

+16 −52
Original line number Diff line number Diff line
@@ -1078,6 +1078,16 @@ void *xquad_portio; 
EXPORT_SYMBOL(xquad_portio);

#endif



/*

 * Fall back to non SMP mode after errors.

 *

 */

static __init void disable_smp(void)

{

	cpu_set(0, cpu_sibling_map[0]);

	cpu_set(0, cpu_core_map[0]);

}



static void __init smp_boot_cpus(unsigned int max_cpus)

{

	int apicid, cpu, bit, kicked;
@@ -1090,7 +1100,6 @@ static void __init smp_boot_cpus(unsigned int max_cpus) 
	printk("CPU%d: ", 0);

	print_cpu_info(&cpu_data[0]);



	boot_cpu_physical_apicid = GET_APIC_ID(apic_read(APIC_ID));

	boot_cpu_logical_apicid = logical_smp_processor_id();

	x86_cpu_to_apicid[0] = boot_cpu_physical_apicid;
@@ -1102,68 +1111,27 @@ static void __init smp_boot_cpus(unsigned int max_cpus) 
	cpus_clear(cpu_core_map[0]);

	cpu_set(0, cpu_core_map[0]);



	map_cpu_to_logical_apicid();



	/*

	 * If we couldn't find an SMP configuration at boot time,

	 * get out of here now!

	 */

	if (!smp_found_config && !acpi_lapic) {

		printk(KERN_NOTICE "SMP motherboard not detected.\n");

		smpboot_clear_io_apic_irqs();

		phys_cpu_present_map = physid_mask_of_physid(0);

		if (APIC_init_uniprocessor())

			printk(KERN_NOTICE "Local APIC not detected."

					   " Using dummy APIC emulation.\n");

		map_cpu_to_logical_apicid();

		cpu_set(0, cpu_sibling_map[0]);

		cpu_set(0, cpu_core_map[0]);

		disable_smp();

		return;

	}



	/*

	 * Should not be necessary because the MP table should list the boot

	 * CPU too, but we do it for the sake of robustness anyway.

	 * Makes no sense to do this check in clustered apic mode, so skip it

	 */

	if (!check_phys_apicid_present(boot_cpu_physical_apicid)) {

		printk("weird, boot CPU (#%d) not listed by the BIOS.\n",

				boot_cpu_physical_apicid);

		physid_set(hard_smp_processor_id(), phys_cpu_present_map);

	}



	/*

	 * If we couldn't find a local APIC, then get out of here now!

	 */

	if (APIC_INTEGRATED(apic_version[boot_cpu_physical_apicid]) && !cpu_has_apic) {

		printk(KERN_ERR "BIOS bug, local APIC #%d not detected!...\n",

			boot_cpu_physical_apicid);

		printk(KERN_ERR "... forcing use of dummy APIC emulation. (tell your hw vendor)\n");

		smpboot_clear_io_apic_irqs();

		phys_cpu_present_map = physid_mask_of_physid(0);

		cpu_set(0, cpu_sibling_map[0]);

		cpu_set(0, cpu_core_map[0]);

		return;

	}



	verify_local_APIC();



	/*

	 * If SMP should be disabled, then really disable it!

	 */

	if (!max_cpus) {

		smp_found_config = 0;

		printk(KERN_INFO "SMP mode deactivated, forcing use of dummy APIC emulation.\n");

		smpboot_clear_io_apic_irqs();

		phys_cpu_present_map = physid_mask_of_physid(0);

		cpu_set(0, cpu_sibling_map[0]);

		cpu_set(0, cpu_core_map[0]);

	if (!max_cpus || (enable_local_apic < 0)) {

		printk(KERN_INFO "SMP mode deactivated.\n");

		disable_smp();

		return;

	}



	connect_bsp_APIC();

	setup_local_APIC();

	map_cpu_to_logical_apicid();





	setup_portio_remap();



	/*
@@ -1244,10 +1212,6 @@ static void __init smp_boot_cpus(unsigned int max_cpus) 
	cpu_set(0, cpu_sibling_map[0]);

	cpu_set(0, cpu_core_map[0]);



	smpboot_setup_io_apic();



	setup_boot_APIC_clock();



	/*

	 * Synchronize the TSC with the AP

	 */

arch/i386/kernel/time.c

+11 −1
Original line number Diff line number Diff line
@@ -444,8 +444,8 @@ static int time_init_device(void) 


device_initcall(time_init_device);



#ifdef CONFIG_HPET_TIMER

extern void (*late_time_init)(void);

#ifdef CONFIG_HPET_TIMER

/* Duplicate of time_init() below, with hpet_enable part added */

static void __init hpet_time_init(void)

{
@@ -462,6 +462,11 @@ static void __init hpet_time_init(void) 
	printk(KERN_INFO "Using %s for high-res timesource\n",cur_timer->name);



	time_init_hook();



#ifdef CONFIG_X86_LOCAL_APIC

	if (enable_local_apic >= 0)

		APIC_late_time_init();

#endif

}

#endif
@@ -486,4 +491,9 @@ void __init time_init(void) 
	printk(KERN_INFO "Using %s for high-res timesource\n",cur_timer->name);



	time_init_hook();



#ifdef CONFIG_X86_LOCAL_APIC

	if (enable_local_apic >= 0)

		late_time_init = APIC_late_time_init;

#endif

}

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