Kernel/arch/i386/cpu/smp.cpp

94 lines
2.3 KiB
C++

/*
This file is part of Fennix Kernel.
Fennix Kernel is free software: you can redistribute it and/or
modify it under the terms of the GNU General Public License as
published by the Free Software Foundation, either version 3 of
the License, or (at your option) any later version.
Fennix Kernel is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
GNU General Public License for more details.
You should have received a copy of the GNU General Public License
along with Fennix Kernel. If not, see <https://www.gnu.org/licenses/>.
*/
#include <smp.hpp>
#include <memory.hpp>
#include <acpi.hpp>
#include <ints.hpp>
#include <assert.h>
#include <cpu.hpp>
#include <atomic>
#include "../../../kernel.h"
#include "apic.hpp"
enum SMPTrampolineAddress
{
PAGE_TABLE = 0x500,
START_ADDR = 0x520,
STACK = 0x570,
GDT = 0x580,
IDT = 0x590,
CORE = 0x600,
TRAMPOLINE_START = 0x2000
};
std::atomic_bool CPUEnabled = false;
#pragma GCC diagnostic ignored "-Wmissing-field-initializers"
static __aligned(PAGE_SIZE) CPUData CPUs[MAX_CPU] = {0};
nsa CPUData *GetCPU(long id) { return &CPUs[id]; }
nsa CPUData *GetCurrentCPU()
{
if (unlikely(!Interrupts::apic[0]))
return &CPUs[0]; /* No APIC means we are on the BSP. */
APIC::APIC *apic = (APIC::APIC *)Interrupts::apic[0];
int CoreID = 0;
if (CPUEnabled.load(std::memory_order_acquire) == true)
{
if (apic->x2APIC)
CoreID = int(CPU::x32::rdmsr(CPU::x32::MSR_X2APIC_APICID));
else
CoreID = apic->Read(APIC::APIC_ID) >> 24;
}
if (unlikely((&CPUs[CoreID])->IsActive != true))
{
error("CPU %d is not active!", CoreID);
assert((&CPUs[0])->IsActive == true); /* We can't continue without the BSP. */
return &CPUs[0];
}
assert((&CPUs[CoreID])->Checksum == CPU_DATA_CHECKSUM); /* This should never happen. */
return &CPUs[CoreID];
}
namespace SMP
{
int CPUCores = 0;
void Initialize(void *_madt)
{
ACPI::MADT *madt = (ACPI::MADT *)_madt;
int Cores = madt->CPUCores + 1;
if (Config.Cores > madt->CPUCores + 1)
KPrint("More cores requested than available. Using %d cores", madt->CPUCores + 1);
else if (Config.Cores != 0)
Cores = Config.Cores;
CPUCores = Cores;
fixme("SMP::Initialize() is not implemented!");
}
}