From 64c57ea3d04afb1469d190cee97619fbc479c050 Mon Sep 17 00:00:00 2001
From: Bananymous <bananymousosq@gmail.com>
Date: Tue, 10 Jan 2023 21:28:59 +0200
Subject: [PATCH] Kernel: Remove obsole CPUID::IsAvailable

This is now a harware requirement that is verified already in boot.S
---
 kernel/arch/i386/APIC.cpp     |  6 ------
 kernel/arch/i386/CPUID.cpp    | 21 ---------------------
 kernel/include/kernel/CPUID.h |  1 -
 kernel/kernel/Shell.cpp       | 10 ----------
 kernel/kernel/kernel.cpp      |  1 +
 5 files changed, 1 insertion(+), 38 deletions(-)

diff --git a/kernel/arch/i386/APIC.cpp b/kernel/arch/i386/APIC.cpp
index 4dca75a4..4c59f4a8 100644
--- a/kernel/arch/i386/APIC.cpp
+++ b/kernel/arch/i386/APIC.cpp
@@ -341,12 +341,6 @@ namespace APIC
 
 	static bool InitializeAPIC()
 	{
-		if (!CPUID::IsAvailable())
-		{
-			kprintln("CPUID not available");
-			return false;
-		}
-
 		uint32_t ecx, edx;
 		CPUID::GetFeatures(ecx, edx);
 		if (!(edx & CPUID::Features::EDX_APIC))
diff --git a/kernel/arch/i386/CPUID.cpp b/kernel/arch/i386/CPUID.cpp
index 02075eff..dadde7e8 100644
--- a/kernel/arch/i386/CPUID.cpp
+++ b/kernel/arch/i386/CPUID.cpp
@@ -12,24 +12,6 @@ namespace CPUID
 		asm volatile ("cpuid": "=a"(out[0]), "=b"(out[0]), "=d"(out[1]), "=c"(out[2]) : "a"(code));
 	}
 
-	bool IsAvailable()
-	{
-		uint32_t res;
-		asm volatile(
-			"pushfl;"
-			"pushfl;"
-			"popl %0;"
-			"xorl %1, %0;"
-			"pushl %0;"
-			"popfl;"
-			"pushfl;"
-			"popl %0;"
-			"popfl;"
-			: "=r"(res)
-			: "i" (0x00200000));
-		return res != 0;
-	}
-
 	const char* GetVendor()
 	{
 		static char vendor[13] {};
@@ -48,9 +30,6 @@ namespace CPUID
 
 	bool Is64Bit()
 	{
-		if (!IsAvailable())
-			return false;
-		
 		uint32_t buffer[4] {};
 		get_cpuid(0x80000000, buffer);
 		if (buffer[0] < 0x80000001)
diff --git a/kernel/include/kernel/CPUID.h b/kernel/include/kernel/CPUID.h
index 6f9cf776..0e9445ac 100644
--- a/kernel/include/kernel/CPUID.h
+++ b/kernel/include/kernel/CPUID.h
@@ -148,7 +148,6 @@ namespace CPUID
 		}
 	}
 
-	bool IsAvailable();
 	const char* GetVendor();
 	void GetFeatures(uint32_t& ecx, uint32_t& edx);
 	bool Is64Bit();
diff --git a/kernel/kernel/Shell.cpp b/kernel/kernel/Shell.cpp
index 839d5558..28418f27 100644
--- a/kernel/kernel/Shell.cpp
+++ b/kernel/kernel/Shell.cpp
@@ -125,11 +125,6 @@ namespace Kernel
 				TTY_PRINTLN("'cpuinfo' does not support command line arguments");
 				return;	
 			}
-			if (!CPUID::IsAvailable())
-			{
-				TTY_PRINTLN("'cpuid' instruction not available");
-				return;
-			}
 
 			uint32_t ecx, edx;
 			auto vendor = CPUID::GetVendor();
@@ -154,11 +149,6 @@ namespace Kernel
 				TTY_PRINTLN("'random' does not support command line arguments");
 				return;	
 			}
-			if (!CPUID::IsAvailable())
-			{
-				TTY_PRINTLN("'cpuid' instruction not available");
-				return;
-			}
 			uint32_t ecx, edx;
 			CPUID::GetFeatures(ecx, edx);
 			if (!(ecx & CPUID::Features::ECX_RDRND))
diff --git a/kernel/kernel/kernel.cpp b/kernel/kernel/kernel.cpp
index 6ef10737..ddc479f2 100644
--- a/kernel/kernel/kernel.cpp
+++ b/kernel/kernel/kernel.cpp
@@ -1,3 +1,4 @@
+#include <BAN/Memory.h>
 #include <kernel/APIC.h>
 #include <kernel/GDT.h>
 #include <kernel/IDT.h>