apic_common.c

 1/*
 2 * Common functions shared between the various APIC flavours
 3 *
 4 * SPDX-License-Identifier: GPL-2.0
 5 */
 6#include <linux/irq.h>
 7#include <linux/kvm_types.h>
 8#include <asm/apic.h>
 9
10#include "local.h"
11
12u32 apic_default_calc_apicid(unsigned int cpu)
13{
14	return per_cpu(x86_cpu_to_apicid, cpu);
15}
16
17u32 apic_flat_calc_apicid(unsigned int cpu)
18{
19	return 1U << cpu;
20}
21
22u32 default_cpu_present_to_apicid(int mps_cpu)
23{
24	if (mps_cpu < nr_cpu_ids && cpu_present(mps_cpu))
25		return (int)per_cpu(x86_cpu_to_apicid, mps_cpu);
26	else
27		return BAD_APICID;
28}
29EXPORT_SYMBOL_FOR_KVM(default_cpu_present_to_apicid);
30
31/*
32 * Set up the logical destination ID when the APIC operates in logical
33 * destination mode.
34 */
35void default_init_apic_ldr(void)
36{
37	unsigned long val;
38
39	apic_write(APIC_DFR, APIC_DFR_FLAT);
40	val = apic_read(APIC_LDR) & ~APIC_LDR_MASK;
41	val |= SET_APIC_LOGICAL_ID(1UL << smp_processor_id());
42	apic_write(APIC_LDR, val);
43}