Merge remote-tracking branch 'Kernel/master'

Kernel/arch/i386/cpu/smp.cpp

@@ -0,0 +1,93 @@
+/*
+	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!");
+	}
+}