Started fleshing out the storage API

kernel/acpi/acpi.cpp

@@ -0,0 +1,35 @@
+#include "acpi.h"
+RSDPDescriptor* ACPI::rsd_ptr;
+RSDT* ACPI::rsd_table;
+
+
+
+void ACPI::initialize(){
+
+    // Find the Root System Description Pointer
+    ACPI::rsd_ptr = FindRSD();
+
+    // is it valid
+    int sum = 0;
+    for (int i =0; i < 20 ; i++) {
+        sum += ((char*)rsd_ptr)[i];
+    }
+
+    printf(" 0x%x sum\n", sum);
+    return;
+
+    //  Get the Root System Description Table
+    RSDT* rootSystemDescriptionTable =  getRSDT((RSDPDescriptor *) rsd_ptr);
+
+    auto tableHeader = &rootSystemDescriptionTable->h;
+
+    // do checksum
+    sum = 0;
+
+    for(int i = 0; i < tableHeader->Length; i ++) {
+        sum += ((char*) tableHeader)[i];
+    }
+
+    if( sum != 0)
+        printf("Table invalid!");
+}

kernel/acpi/acpi.h

@@ -0,0 +1,13 @@
+#pragma once 
+#include "rsdp.h"
+class ACPI {
+    public:
+        static void initialize();
+        
+        // In the future ACPI might start
+        // doing more systems initialization
+        
+    private:
+       static RSDPDescriptor* rsd_ptr;
+       static RSDT* rsd_table;
+};

kernel/acpi/rsdp.cpp

@@ -0,0 +1,40 @@
+#include "rsdp.h"
+#include "../memory/VirtualMemoryManager.h"
+
+
+void printRSD(RSDPDescriptor* rsd){
+    printf("Signature: ");
+    for(int i = 0; i < 8; i++){
+        kterm_put(rsd->signature[i]);
+    }
+    kterm_put('\n');
+
+    printf("OEMID: ");
+    for(int i =0; i < 6 ; i++){
+        kterm_put (rsd->OEMID[i]);
+    }
+    kterm_put('\n');
+
+    printf("Revision: %d\n", rsd->Revision);
+    printf("RSDT Address: 0x%x\n", rsd->RsdtAddress );
+}
+
+RSDPDescriptor* FindRSD(){
+    char* memory_byte = (char*) 0x000f2e14;
+    const void* string = "RSD PTR ";
+
+    for( ; (uint32_t) memory_byte < 0x00100000; memory_byte+=10){
+        if( memcmp(memory_byte , string , 8 ) ==  0 ) {
+        printf("RSD PTR found at 0x%x !\n", memory_byte);
+        break;
+        }
+    }
+    return (RSDPDescriptor*) memory_byte;
+}
+
+
+RSDT* getRSDT(RSDPDescriptor* rsd){
+    printf("rsdt Address: 0x%x\n", rsd->RsdtAddress);
+    return (RSDT*)rsd->RsdtAddress ;
+
+}

kernel/acpi/rsdp.h

@@ -0,0 +1,35 @@
+#pragma once
+#include "../terminal/kterm.h"
+#include <CoreLib/Memory.h>
+#include <stdint-gcc.h>
+
+struct RSDPDescriptor {
+    char signature[8];
+    uint8_t Checksum ;
+    char OEMID [6];
+    uint8_t Revision;
+    uint32_t RsdtAddress;
+}__attribute__((packed));
+
+struct ACPISDTHeader{
+    char Signature[4];
+    uint32_t Length;
+    uint8_t Revision;
+    uint8_t CheckSum;
+    char OEMID[6];
+    char OEMTableID[8];
+    uint32_t OEMRevision;
+    uint32_t CreatorID;
+    uint32_t CreatorRevision;
+};
+
+
+struct RSDT{
+    struct ACPISDTHeader h;
+    uint32_t PointerToSDT[]; // Length of array : (header.Length - sizeof(header))/ 4
+}__attribute__((packed));
+RSDPDescriptor* FindRSD();
+
+void printRSD(RSDPDescriptor* rsd);
+
+RSDT* getRSDT(RSDPDescriptor* rsd);