blob: 7b1e0e1365ed1fd6a99529d28ae6fa2fd3a90e7d [file] [log] [blame]
#include <libcflat.h>
#include "processor.h"
#include "atomic.h"
#include "smp.h"
#include "apic.h"
#include "fwcfg.h"
#include "desc.h"
#define IPI_VECTOR 0x20
typedef void (*ipi_function_type)(void *data);
static struct spinlock ipi_lock;
static volatile ipi_function_type ipi_function;
static void *volatile ipi_data;
static volatile int ipi_done;
static volatile bool ipi_wait;
static int _cpu_count;
static atomic_t active_cpus;
static __attribute__((used)) void ipi(void)
{
void (*function)(void *data) = ipi_function;
void *data = ipi_data;
bool wait = ipi_wait;
if (!wait) {
ipi_done = 1;
apic_write(APIC_EOI, 0);
}
function(data);
atomic_dec(&active_cpus);
if (wait) {
ipi_done = 1;
apic_write(APIC_EOI, 0);
}
}
asm (
"ipi_entry: \n"
" call ipi \n"
#ifndef __x86_64__
" iret"
#else
" iretq"
#endif
);
int cpu_count(void)
{
return _cpu_count;
}
int smp_id(void)
{
unsigned id;
asm ("mov %%gs:0, %0" : "=r"(id));
return id;
}
static void setup_smp_id(void *data)
{
asm ("mov %0, %%gs:0" : : "r"(apic_id()) : "memory");
}
static void __on_cpu(int cpu, void (*function)(void *data), void *data,
int wait)
{
unsigned int target = id_map[cpu];
spin_lock(&ipi_lock);
if (target == smp_id())
function(data);
else {
atomic_inc(&active_cpus);
ipi_done = 0;
ipi_function = function;
ipi_data = data;
ipi_wait = wait;
apic_icr_write(APIC_INT_ASSERT | APIC_DEST_PHYSICAL | APIC_DM_FIXED
| IPI_VECTOR, target);
while (!ipi_done)
;
}
spin_unlock(&ipi_lock);
}
void on_cpu(int cpu, void (*function)(void *data), void *data)
{
__on_cpu(cpu, function, data, 1);
}
void on_cpu_async(int cpu, void (*function)(void *data), void *data)
{
__on_cpu(cpu, function, data, 0);
}
void on_cpus(void (*function)(void *data), void *data)
{
int cpu;
for (cpu = cpu_count() - 1; cpu >= 0; --cpu)
on_cpu_async(cpu, function, data);
while (cpus_active() > 1)
pause();
}
int cpus_active(void)
{
return atomic_read(&active_cpus);
}
void smp_init(void)
{
int i;
void ipi_entry(void);
_cpu_count = fwcfg_get_nb_cpus();
setup_idt();
init_apic_map();
set_idt_entry(IPI_VECTOR, ipi_entry, 0);
setup_smp_id(0);
for (i = 1; i < cpu_count(); ++i)
on_cpu(i, setup_smp_id, 0);
atomic_inc(&active_cpus);
}