linux-stable-rt/arch/x86/kernel/genapic_64.c

74 lines
1.8 KiB
C

/*
* Copyright 2004 James Cleverdon, IBM.
* Subject to the GNU Public License, v.2
*
* Generic APIC sub-arch probe layer.
*
* Hacked for x86-64 by James Cleverdon from i386 architecture code by
* Martin Bligh, Andi Kleen, James Bottomley, John Stultz, and
* James Cleverdon.
*/
#include <linux/threads.h>
#include <linux/cpumask.h>
#include <linux/string.h>
#include <linux/module.h>
#include <linux/kernel.h>
#include <linux/ctype.h>
#include <linux/init.h>
#include <asm/smp.h>
#include <asm/ipi.h>
#include <asm/genapic.h>
#ifdef CONFIG_ACPI
#include <acpi/acpi_bus.h>
#endif
/*
* which logical CPU number maps to which CPU (physical APIC ID)
*
* The following static array is used during kernel startup
* and the x86_cpu_to_apicid_ptr contains the address of the
* array during this time. Is it zeroed when the per_cpu
* data area is removed.
*/
u8 x86_cpu_to_apicid_init[NR_CPUS] __initdata
= { [0 ... NR_CPUS-1] = BAD_APICID };
void *x86_cpu_to_apicid_ptr;
DEFINE_PER_CPU(u8, x86_cpu_to_apicid) = BAD_APICID;
EXPORT_PER_CPU_SYMBOL(x86_cpu_to_apicid);
struct genapic __read_mostly *genapic = &apic_flat;
/*
* Check the APIC IDs in bios_cpu_apicid and choose the APIC mode.
*/
void __init setup_apic_routing(void)
{
#ifdef CONFIG_ACPI
/*
* Quirk: some x86_64 machines can only use physical APIC mode
* regardless of how many processors are present (x86_64 ES7000
* is an example).
*/
if (acpi_gbl_FADT.header.revision > FADT2_REVISION_ID &&
(acpi_gbl_FADT.flags & ACPI_FADT_APIC_PHYSICAL))
genapic = &apic_physflat;
else
#endif
if (cpus_weight(cpu_possible_map) <= 8)
genapic = &apic_flat;
else
genapic = &apic_physflat;
printk(KERN_INFO "Setting APIC routing to %s\n", genapic->name);
}
/* Same for both flat and physical. */
void send_IPI_self(int vector)
{
__send_IPI_shortcut(APIC_DEST_SELF, vector, APIC_DEST_PHYSICAL);
}