starting work on page tables

kernel/src/BasicRenderer.cpp

@@ -3,17 +3,18 @@
 BasicRenderer::BasicRenderer(Framebuffer* framebuffer, PSF1_FONT* psf1_Font) {
 	targetFramebuffer = framebuffer;
 	PSF1_Font = psf1_Font;
+	Colour = 0xFFFFFFFF;
 	cursorPosition = {0,0};
 }
 
-void BasicRenderer::PutChar(unsigned int colour, char chr, unsigned int xOff, unsigned int yOff) {
+void BasicRenderer::PutChar(char chr, unsigned int xOff, unsigned int yOff) {
 	unsigned int* pixPtr = (unsigned int*)targetFramebuffer->BaseAddress;
 	char* fontPtr = (char*)PSF1_Font->glyphBuffer + (chr * PSF1_Font->psf1_Header->charsize);
 	for (unsigned long y = yOff; y < yOff + 18; y++) {
 		for (unsigned long x = xOff; x < xOff+8; x++) {
 			
 			if ((*fontPtr & (0b10000000 >> (x - xOff))) > 0) {
-				*(unsigned int*)(pixPtr + x + (y * targetFramebuffer->PixelsPerScanline)) = colour;
+				*(unsigned int*)(pixPtr + x + (y * targetFramebuffer->PixelsPerScanline)) = Colour;
 			}
 
 		}
@@ -22,12 +23,12 @@ void BasicRenderer::PutChar(unsigned int colour, char chr, unsigned int xOff, un
 	}
 }
 
-void BasicRenderer::Print(unsigned int colour, const char* str) {
+void BasicRenderer::Print(const char* str) {
 	unsigned int x = 0;
 	char* chr = (char*)str;
 
 	while (*chr != 0) {
-		PutChar(colour, *chr, cursorPosition.x, cursorPosition.y);
+		PutChar(*chr, cursorPosition.x, cursorPosition.y);
 		cursorPosition.x+=8;
 
 		if (cursorPosition.x + 8 > targetFramebuffer->Width) {

kernel/src/BasicRenderer.h

@@ -9,6 +9,7 @@ class BasicRenderer {
 		Point cursorPosition;
 		Framebuffer* targetFramebuffer;
 		PSF1_FONT* PSF1_Font;
-		void Print(unsigned int colour, const char* str);
+		unsigned int Colour;
-		void PutChar(unsigned int colour, char chr, unsigned int xOff, unsigned int yOff);
+		void Print(const char* str);
+		void PutChar(char chr, unsigned int xOff, unsigned int yOff);
 };

kernel/src/kernel.cpp

@@ -5,7 +5,8 @@
 #include "efiMemory.h"
 #include "memory.h"
 #include "Bitmap.h"
-#include "PageFrameAllocator.h"
+#include "paging/PageFrameAllocator.h"
+#include "paging/PageMapIndexer.h"
 
 struct BootInfo {
 	Framebuffer* framebuffer;
@@ -40,19 +41,15 @@ extern "C" void _start(BootInfo* bootInfo) {
 
 	newAllocator.LockPages(&_KernelStart, kernelPages);
 
-	// print out ram info
+	PageMapIndexer pageIndexer = PageMapIndexer(0x1000);
-	newRenderer.Print(0xFFFFFFFF, "Free RAM: ");
+
-	newRenderer.Print(0xFF00FFFF, to_string(newAllocator.GetFreeRAM() / 1024));
+	newRenderer.Print(to_string(pageIndexer.P_i));
-	newRenderer.Print(0xFF00FFFF, " KB");
+	newRenderer.Print(" - ");
-	newRenderer.cursorPosition = {0, newRenderer.cursorPosition.y + 18};
+	newRenderer.Print(to_string(pageIndexer.PT_i));
-	newRenderer.Print(0xFFFFFFFF, "Used RAM: ");
+	newRenderer.Print(" - ");
-	newRenderer.Print(0xFF00FFFF, to_string(newAllocator.GetUsedRAM() / 1024));
+	newRenderer.Print(to_string(pageIndexer.PD_i));
-	newRenderer.Print(0xFF00FFFF, " KB");
+	newRenderer.Print(" - ");
-	newRenderer.cursorPosition = {0, newRenderer.cursorPosition.y + 18};
+	newRenderer.Print(to_string(pageIndexer.PDP_i));
-	newRenderer.Print(0xFFFFFFFF, "Reserved RAM: ");
-	newRenderer.Print(0xFF00FFFF, to_string(newAllocator.GetReservedRAM() / 1024));
-	newRenderer.Print(0xFF00FFFF, " KB");
-	newRenderer.cursorPosition = {0, newRenderer.cursorPosition.y + 18};
 
 	return;
 }

kernel/src/paging/PageFrameAllocator.h

@@ -1,9 +1,9 @@
 #pragma once
 
-#include "efiMemory.h"
+#include "../efiMemory.h"
 #include <stdint.h>
-#include "Bitmap.h"
+#include "../Bitmap.h"
-#include "memory.h"
+#include "../memory.h"
 
 class PageFrameAllocator {
     public:

kernel/src/paging/PageMapIndexer.cpp

@@ -0,0 +1,12 @@
+#include "PageMapIndexer.h"
+
+PageMapIndexer::PageMapIndexer(uint64_t virtualAddress) {
+	virtualAddress >>= 12; // 4096 aligned
+	P_i = virtualAddress & 0x1FF;
+	virtualAddress >>= 9;
+	PT_i = virtualAddress & 0x1FF;
+	virtualAddress >>= 9;
+	PD_i = virtualAddress & 0x1FF;
+	virtualAddress >>= 9;
+	PDP_i = virtualAddress & 0x1FF;
+}

kernel/src/paging/PageMapIndexer.h

@@ -0,0 +1,11 @@
+#pragma once
+#include <stdint.h>
+
+class PageMapIndexer {
+	public:
+		PageMapIndexer(uint64_t virtualAddress);
+		uint64_t PDP_i;
+		uint64_t PD_i;
+		uint64_t PT_i;
+		uint64_t P_i;
+};

kernel/src/paging/paging.h

@@ -0,0 +1,21 @@
+#pragma once
+#include <stdint.h>
+
+struct PageDirectoryEntry {
+	bool Present : 1; // memory exists and can be accessed
+	bool ReadWrite : 1; // 
+	bool UserSuper : 1; // memory can only be accessed by supervisor or both user and supervisor
+	bool WriteThrough : 1; //
+	bool CacheDisabled : 1; //
+	bool Accessed : 1; // set when cpu accesses page
+	bool ignore0 : 1; //
+	bool LargerPages : 1; //
+	bool ignore1 : 1; //
+	uint8_t Available : 3; //
+	uint64_t Address : 52; // physical address
+
+};
+
+struct PageTable {
+	PageDirectoryEntry entries[512];
+}__attribute__((aligned(0x1000)));