Quelle  x2apic_phys.c   Sprache: C

// SPDX-License-Identifier: GPL-2.0

#include <linux/cpumask.h>
#include <linux/acpi.h>

#include "local.h"

int x2apic_phys;

static struct apic apic_x2apic_phys;
u32 x2apic_max_apicid __ro_after_init = UINT_MAX;

void __init x2apic_set_max_apicid(u32 apicid)
{
 x2apic_max_apicid = apicid;
 if (apic->x2apic_set_max_apicid)
  apic->max_apic_id = apicid;
}

static int __init set_x2apic_phys_mode(char *arg)
{
 x2apic_phys = 1;
 return 0;
}
early_param("x2apic_phys", set_x2apic_phys_mode);

static bool x2apic_fadt_phys(void)
{
#ifdef CONFIG_ACPI
 if ((acpi_gbl_FADT.header.revision >= FADT2_REVISION_ID) &&
  (acpi_gbl_FADT.flags & ACPI_FADT_APIC_PHYSICAL)) {
  printk(KERN_DEBUG "System requires x2apic physical mode\n");
  return true;
 }
#endif
 return false;
}

static int x2apic_acpi_madt_oem_check(char *oem_id, char *oem_table_id)
{
 return x2apic_enabled() && (x2apic_phys || x2apic_fadt_phys());
}

static void x2apic_send_IPI(int cpu, int vector)
{
 u32 dest = per_cpu(x86_cpu_to_apicid, cpu);

 /* x2apic MSRs are special and need a special fence: */
 weak_wrmsr_fence();
 __x2apic_send_IPI_dest(dest, vector, APIC_DEST_PHYSICAL);
}

static void
__x2apic_send_IPI_mask(const struct cpumask *mask, int vector, int apic_dest)
{
 unsigned long query_cpu;
 unsigned long this_cpu;
 unsigned long flags;

 /* x2apic MSRs are special and need a special fence: */
 weak_wrmsr_fence();

 local_irq_save(flags);

 this_cpu = smp_processor_id();
 for_each_cpu(query_cpu, mask) {
  if (apic_dest == APIC_DEST_ALLBUT && this_cpu == query_cpu)
   continue;
  __x2apic_send_IPI_dest(per_cpu(x86_cpu_to_apicid, query_cpu),
           vector, APIC_DEST_PHYSICAL);
 }
 local_irq_restore(flags);
}

static void x2apic_send_IPI_mask(const struct cpumask *mask, int vector)
{
 __x2apic_send_IPI_mask(mask, vector, APIC_DEST_ALLINC);
}

static void
 x2apic_send_IPI_mask_allbutself(const struct cpumask *mask, int vector)
{
 __x2apic_send_IPI_mask(mask, vector, APIC_DEST_ALLBUT);
}

static void __x2apic_send_IPI_shorthand(int vector, u32 which)
{
 unsigned long cfg = __prepare_ICR(which, vector, 0);

 /* x2apic MSRs are special and need a special fence: */
 weak_wrmsr_fence();
 native_x2apic_icr_write(cfg, 0);
}

void x2apic_send_IPI_allbutself(int vector)
{
 __x2apic_send_IPI_shorthand(vector, APIC_DEST_ALLBUT);
}

void x2apic_send_IPI_all(int vector)
{
 __x2apic_send_IPI_shorthand(vector, APIC_DEST_ALLINC);
}

void x2apic_send_IPI_self(int vector)
{
 apic_write(APIC_SELF_IPI, vector);
}

void __x2apic_send_IPI_dest(unsigned int apicid, int vector, unsigned int dest)
{
 unsigned long cfg = __prepare_ICR(0, vector, dest);
 native_x2apic_icr_write(cfg, apicid);
}

static int x2apic_phys_probe(void)
{
 if (!x2apic_mode)
  return 0;

 if (x2apic_phys || x2apic_fadt_phys())
  return 1;

 return apic == &apic_x2apic_phys;
}

u32 x2apic_get_apic_id(u32 id)
{
 return id;
}

static struct apic apic_x2apic_phys __ro_after_init = {

 .name    = "physical x2apic",
 .probe    = x2apic_phys_probe,
 .acpi_madt_oem_check  = x2apic_acpi_madt_oem_check,

 .dest_mode_logical  = false,

 .disable_esr   = 0,

 .cpu_present_to_apicid  = default_cpu_present_to_apicid,

 .max_apic_id   = UINT_MAX,
 .x2apic_set_max_apicid  = true,
 .get_apic_id   = x2apic_get_apic_id,

 .calc_dest_apicid  = apic_default_calc_apicid,

 .send_IPI   = x2apic_send_IPI,
 .send_IPI_mask   = x2apic_send_IPI_mask,
 .send_IPI_mask_allbutself = x2apic_send_IPI_mask_allbutself,
 .send_IPI_allbutself  = x2apic_send_IPI_allbutself,
 .send_IPI_all   = x2apic_send_IPI_all,
 .send_IPI_self   = x2apic_send_IPI_self,
 .nmi_to_offline_cpu  = true,

 .read    = native_apic_msr_read,
 .write    = native_apic_msr_write,
 .eoi    = native_apic_msr_eoi,
 .icr_read   = native_x2apic_icr_read,
 .icr_write   = native_x2apic_icr_write,
};

apic_driver(apic_x2apic_phys);