Debugging paging problem on VirtualBox (VT-x)

10 files changed, 176 insertions, 70 deletions

diff --git a/boot/disk_load_16.asm b/boot/disk_load_16.asm
index 4222dd9..e45b89a 100644
--- a/boot/disk_load_16.asm
+++ b/boot/disk_load_16.asm
@@ -7,8 +7,8 @@
 
 [bits 16]
 
-DISK_LOAD_HANG_MSG:
-    db " D",0
+DISK_LOAD:
+    db "D",0
 
 ;disk_load routune (load dh sectors from drive dl to es:bx)
 ;lba mode has 52 sectors hardcoded!
@@ -48,10 +48,8 @@ disk_load_lba:
     lea si,[lba_adr]        
     int 0x13  
     jc skip_print
-
-    mov bx, 0x1000
+    mov bx, DISK_LOAD
     call print_string
-
     skip_print:
 
     popa
diff --git a/boot/mbr.asm b/boot/mbr.asm
index 4ece914..ca851c3 100644
--- a/boot/mbr.asm
+++ b/boot/mbr.asm
@@ -61,7 +61,7 @@ jmp $ ;entry for other processors ;)
 BOOT_DRIVE:
     db 0xff
 STR_VERSION:
-    db "v0.4",0
+    db "v0.5",0
 VESA_CHECK1:
     db "1",0
 VESA_CHECK2:
@@ -145,17 +145,30 @@ boot_32_pm:
 ;    ;http://www.brokenthorn.com/Resources/OSDev9.html
 ;    ;Method 3.1: Enables A20 through keyboard controller
 ;    ;Not all keyboard controllers support this
-;    ;todo: check if this has any effect at all !?!?
-     mov al, 0xdd  ; command 0xdd: enable a20
-;   ;mov al, 0xdf  ; command 0xdf: disable a20
-     out 0x64, al  ; send command to controller
+;    ; does not work in virtual box (with VT-x accerleration?) 
 
-     mov eax,0
-;
+;     mov al, 0xdd  ; command 0xdd: enable a20
+;     mov al, 0xdf  ; command 0xdf: disable a20
+;     out 0x64, al  ; send command to controller
+
+    ;Fast A20 Gate:
+    ;http://wiki.osdev.org/A20_Line
+    
+    in al, 0x92
+    or al, 2
+    out 0x92, al
+
+    ; call kernel!
+    mov eax,0					;booting processor
     call KERNEL_OFFSET			        ;jump into our Kernel!
 ;
 ;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
 ;
+
+;fill partition table (4x16byte) with zeroes. 
+;(otherwise my Acer Aspire will not boot)
+times 64 db 0x0
+
 ;so we get identified as MBR
 times 510-($-$$) db 0x0
 ;dw 0x0
diff --git a/boot/pm.asm b/boot/pm.asm
index 8a4f745..73bb9d3 100644
--- a/boot/pm.asm
+++ b/boot/pm.asm
@@ -11,6 +11,7 @@ switch_to_pm:
 
     cli				;switch off interrupts!
     lgdt [gdt_descriptor]	;load descriptor table!
+    lldt [gdt_descriptor]	;load descriptor table! (local)
 
     ;switch on 32-bit protected mode
     mov eax, cr0
diff --git a/boot/vesa_setup_16.asm b/boot/vesa_setup_16.asm
index 7180252..96e16e2 100644
--- a/boot/vesa_setup_16.asm
+++ b/boot/vesa_setup_16.asm
@@ -33,16 +33,15 @@ VesaSetup:
     jmp vesa_err2
     vesa_ok2:
 
-
     ;VESA: finally switch to the mode of choice!
     mov ax,0x4f02   ;vesa function: Set Mode
     mov bx,VESA_MODE_SELECT 
     int 0x10
-    vesa_err3:
-    mov bx, VESA_CHECK3
-    call print_string
     cmp ax,0x004f
     je vesa_ok3
+    vesa_err3
+    mov bx, VESA_CHECK3
+    call print_string
     jmp vesa_err3
     vesa_ok3:
     popa
diff --git a/kernel/console.c b/kernel/console.c
index 72ad066..16cf04f 100644
--- a/kernel/console.c
+++ b/kernel/console.c
@@ -1,6 +1,6 @@
 #include "console.h"
 
-//#define FOOLOS_CONSOLE
+#define FOOLOS_CONSOLE
 //#undef FOOLOS_CONSOLE
 
 static int posx=0;
@@ -10,11 +10,11 @@ static int posy=0;
 
 void print_char_col(int x, int y, char c, char col)
 {
-#ifdef FOOLOS_CONSOLE
+//#ifdef FOOLOS_CONSOLE
     char* video_mem=(char *)SCR_VIDEOMEM+(x+y*SCR_REAL_WIDTH)*2;
     video_mem[0]=c;
     video_mem[1]=col;
-#endif
+//#endif
 }
 
 void print_char(int x, int y, char c)
diff --git a/kernel/kernel.c b/kernel/kernel.c
index 7bbfcce..429a286 100644
--- a/kernel/kernel.c
+++ b/kernel/kernel.c
@@ -25,22 +25,17 @@ void kernel_main(uint32_t initial_stack, int mp)
 {
 
 
+    volatile static uint32_t cpu1_counter=0;
+
     // catch the APs (Application Processors)
+    /*
     if(mp==1)
     {
-	uint16_t c3=0;
-	while(1)
-	{
-
-
-	    c3++;
-	    asm("cli");
-
-	    PutString("cpu2: %03d", 200,560,0b1111100000000000, c3/100);
-
-	    asm("sti");
-	}
+	//while(1) { static uint16_t c=0; PutString("cpu2: %03d", 200,560,0b1111100000000000, (c++)/100); }
+	while(1) { static uint16_t c=0; PutString("cpu1counter: %d", 200,560,0b1111100000000000, (cpu1_counter)); }
     }
+    */
+
 
     // 
     // We want to get output to the screen as fast as possible!
@@ -62,7 +57,6 @@ void kernel_main(uint32_t initial_stack, int mp)
     //  our video memory 
     //
 
-
     uint32_t vesa_physbase=vesa_init(0x8300,0x8400,0x7200);
 
 
@@ -72,8 +66,6 @@ void kernel_main(uint32_t initial_stack, int mp)
 
     log(FOOLOS_MODULE_NAME,FOOLOS_LOG_INFO,"initial esp: 0x%08X",initial_stack);
 
-    log(FOOLOS_MODULE_NAME,FOOLOS_LOG_INFO,"mp: %d",mp);
-
     //
     // Initialize other processors
     //
@@ -81,10 +73,26 @@ void kernel_main(uint32_t initial_stack, int mp)
     //	Should support APCI in future too.
     //
     
+
     if(!init_mp()) panic(FOOLOS_MODULE_NAME,"Can not Find _MP_");
 
 
     //
+    //	Memory Init
+    //
+
+    // we know that here, the bootloader placed the mamory map!
+    mem_init(0x7c00+0x400,*((uint16_t *)(0x7c00+0x600)));
+
+    
+    // paging  (pass the vesa physbase address for identity mapping)
+    vmem_init(vesa_physbase);
+
+    while(1) { 
+	PutString("cpu1counter: %d", 10,560,0b1111100000000000, (cpu1_counter));
+	cpu1_counter++;
+    }
+    //
     //  Setup PIC
     //
     //  Do we nee this when using APIC?
@@ -103,17 +111,6 @@ void kernel_main(uint32_t initial_stack, int mp)
 
 
     //
-    //	Memory Init
-    //
-
-    // we know that here, the bootloader placed the mamory map!
-    mem_init(0x7c00+0x400,*((uint16_t *)(0x7c00+0x600)));
-    
-    // paging  (pass the vesa physbase address for identity mapping)
-    vmem_init(vesa_physbase);
-
-
-    //
     // Interrupts
     //
 
@@ -136,8 +133,19 @@ void kernel_main(uint32_t initial_stack, int mp)
     int_install_ir(38, 0b10001110, 0x08,&int_floppy_handler);
 
     // now we can enable interrupts back again
-    int_enable();
-
+//    int_enable();
+
+    while(1) { 
+	cpu1_counter++;
+	/*
+	static uint16_t c=0; 
+	PutString("cpu1: A",20,560,0xffffff,0); 
+	for(int c2=0;c2<0xffff;c2++);
+	PutString("cpu1: B",20,560,0xffffff,0); 
+	for(int c2=0;c2<0xffff;c2++);
+	//PutString("cpu1: %03d", 20,560,0b1111100000000000, (c++)/100); 
+	*/
+    }
 
     //
     // Scan the PCI Bus
diff --git a/kernel/vesa.c b/kernel/vesa.c
index b7b4615..a3fc76c 100644
--- a/kernel/vesa.c
+++ b/kernel/vesa.c
@@ -57,6 +57,12 @@ static console_y;
 static console_lines;
 static console_cols;
 
+void vesa_set_physbase(uint32_t addr)
+{
+    VbeModeInfoBlock->physbase=addr;
+}
+
+
 uint32_t vesa_init(vbeinfo *info,vbemodeinfo *mode,foolfont *rawfont)
 {
     //the only functionallu important init lines! (rest is log)
@@ -180,12 +186,12 @@ void PutConsoleNL()
 {
     console_x=0;
     console_y++;
-    if(console_y>console_lines)console_y=1;
+    if(console_y>=console_lines)console_y=0;
+
     for(int i=0;i<console_cols;i++)
     {
-	PutFont(' ',i*10,(console_y+1)*12,0);
+	PutFont(' ',i*10,(console_y)*12,0);
     }
-
 }
 
 
diff --git a/kernel/vmem.c b/kernel/vmem.c
index 8590579..741a1e8 100644
--- a/kernel/vmem.c
+++ b/kernel/vmem.c
@@ -7,7 +7,8 @@
 
 
 // TODO : why is the frame not 0xfffff??
-enum PAGE_PTE_FLAGS {
+enum PAGE_PTE_FLAGS 
+{
  
     I86_PTE_PRESENT		=	1,		//0000000000000000000000000000001
     I86_PTE_WRITABLE		=	2,		//0000000000000000000000000000010
@@ -22,7 +23,8 @@ enum PAGE_PTE_FLAGS {
     I86_PTE_FRAME		=	0xFFFFF000 	//1111111111111111111000000000000
 };
 
-enum PAGE_PDE_FLAGS {
+enum PAGE_PDE_FLAGS 
+{
  
     I86_PDE_PRESENT		=	1,		//0000000000000000000000000000001
     I86_PDE_WRITABLE		=	2,		//0000000000000000000000000000010
@@ -194,6 +196,17 @@ void vmmngr_map_page (void* phys, void* virt)
 
 }
 
+void show_cr()
+{
+
+    log(FOOLOS_MODULE_NAME,FOOLOS_LOG_INFO,"cr0: 0x%08x",x86_get_cr0());
+    log(FOOLOS_MODULE_NAME,FOOLOS_LOG_INFO,"cr1: 0x%08x",x86_get_cr1());
+    log(FOOLOS_MODULE_NAME,FOOLOS_LOG_INFO,"cr2: 0x%08x",x86_get_cr2());
+    log(FOOLOS_MODULE_NAME,FOOLOS_LOG_INFO,"cr3: 0x%08x",x86_get_cr3());
+    log(FOOLOS_MODULE_NAME,FOOLOS_LOG_INFO,"cr4: 0x%08x",x86_get_cr4());
+
+}
+
 void vmem_init(uint32_t vesa_physbase)
 {
     log(FOOLOS_MODULE_NAME,FOOLOS_LOG_INFO,"init paging (vesa base: 0x%08x)",vesa_physbase);
@@ -213,33 +226,38 @@ void vmem_init(uint32_t vesa_physbase)
     if (!dir)panic(FOOLOS_MODULE_NAME,"unable to alloc pdirectory");
     log(FOOLOS_MODULE_NAME,FOOLOS_LOG_INFO,"pdirectory: 0x%X",dir);
 
-    //! map 1mb to 3gb (where we are at)
-    for (int i=0, frame=vesa_physbase, virt=vesa_physbase; i<1024; i++, frame+=4096, virt+=4096) {
-
+    //! 1st 4mb are idenitity mapped
+    for (int i=0, frame=0x0, virt=0x00000000; i<1024; i++, frame+=4096, virt+=4096) 
+    {
 	//! create a new page
 	pt_entry page=0;
 	pt_entry_add_attrib (&page, I86_PTE_PRESENT);
 	pt_entry_set_frame (&page, frame);
 
 	//! ...and add it to the page table
-	table1->m_entries [PAGE_TABLE_INDEX (virt) ] = page;
+	table2->m_entries [PAGE_TABLE_INDEX (virt) ] = page;
     }
 
-    //! 1st 4mb are idenitity mapped
-    for (int i=0, frame=0x0, virt=0x00000000; i<1024; i++, frame+=4096, virt+=4096) 
+    //! map 1mb to 3gb (where we are at)
+
+    uint32_t vesa_mapped=0x1000*1024;
+
+    for (int i=0, frame=vesa_physbase, virt=vesa_mapped; i<1024; i++, frame+=4096, virt+=4096) 
     {
 
 	//! create a new page
 	pt_entry page=0;
 	pt_entry_add_attrib (&page, I86_PTE_PRESENT);
+//	pt_entry_add_attrib (&page, I86_PTE_WRITABLE);
 	pt_entry_set_frame (&page, frame);
 
 	//! ...and add it to the page table
-	table2->m_entries [PAGE_TABLE_INDEX (virt) ] = page;
+	table1->m_entries [PAGE_TABLE_INDEX (virt) ] = page;
     }
 
+    for(int i=0;i<1024;i++)dir->m_entries [i]=0;
    
-    pd_entry* entry = &dir->m_entries [PAGE_DIRECTORY_INDEX (vesa_physbase) ];
+    pd_entry* entry = &dir->m_entries [PAGE_DIRECTORY_INDEX (vesa_mapped) ];
     *entry=0;
     pd_entry_add_attrib (entry, I86_PDE_PRESENT);
     pd_entry_add_attrib (entry, I86_PDE_WRITABLE);
@@ -252,16 +270,23 @@ void vmem_init(uint32_t vesa_physbase)
     pd_entry_add_attrib (entry2, I86_PDE_WRITABLE);
     pd_entry_set_frame (entry2, (physical_addr)table2);
 
-
-
-
     x86_set_pdbr(dir);
 
     log(FOOLOS_MODULE_NAME,FOOLOS_LOG_INFO,"enabling paging...");
+
+    show_cr();
+
+    // while(1);
+    
+    x86_paging_enable();
+    x86_paging_disable();
     x86_paging_enable();
+    vesa_set_physbase(vesa_mapped);
+
+    // x86_flush_tlb(0);
+    // x86_flush_tlb(vesa_physbase);
 
-    x86_flush_tlb(0);
-    x86_flush_tlb(vesa_physbase);
+    show_cr();
 
 }
 
diff --git a/kernel/x86.c b/kernel/x86.c
index 94f4f89..c1113bf 100644
--- a/kernel/x86.c
+++ b/kernel/x86.c
@@ -1,5 +1,45 @@
 #include "x86.h"
 
+// get control registers (cr0-cr4)
+
+uint32_t x86_get_cr0()
+{
+    uint32_t cr;
+    asm volatile("mov %%cr0, %0": "=b"(cr));
+    return cr;
+}
+
+uint32_t x86_get_cr1()
+{
+    uint32_t cr=0;
+    
+    // reading the reserved cr1 register results in crash.
+    // (at least on emulators)
+    // asm volatile("mov %%cr1, %0": "=b"(cr));
+    
+    return cr;
+}
+
+uint32_t x86_get_cr2()
+{
+    uint32_t cr;
+    asm volatile("mov %%cr2, %0": "=b"(cr));
+    return cr;
+}
+
+uint32_t x86_get_cr3()
+{
+    uint32_t cr=0;
+    asm volatile("mov %%cr3, %0": "=b"(cr));
+    return cr;
+}
+
+uint32_t x86_get_cr4()
+{
+    uint32_t cr;
+    asm volatile("mov %%cr4, %0": "=b"(cr));
+    return cr;
+}
 void x86_outb(int port, uint8_t data)
 {
     __asm __volatile("outb %0,%w1" : : "a" (data), "d" (port));
@@ -43,15 +83,31 @@ void x86_set_pdbr(uint32_t addr)
 
 }
 
+// enable PT bit in CR0
 void x86_paging_enable()
 {
-    unsigned int cr0;
-    asm volatile("mov %%cr0, %0": "=b"(cr0));
-    cr0 |= 0x80000000;
+    uint32_t cr0=x86_get_cr0();
+    cr0 |= 0x80000000; // enable paging 
+
+//    cr0 |= 0x40000000; // cahce disable
+//    cr0 |= 0x20000000; // not-write-through
+//    cr0 |= 0x10000; // write to read-only pages
+
+    asm volatile("mov %0, %%cr0":: "b"(cr0));
+}
+
+
+// disable PT bit in CR0
+void x86_paging_disable()
+{
+    uint32_t cr0=x86_get_cr0();
+    cr0 &= ~0x80000000;
     asm volatile("mov %0, %%cr0":: "b"(cr0));
 }
 
-x86_flush_tlb(uint32_t addr)
+void x86_flush_tlb(uint32_t addr)
 {
 	asm volatile("invlpg (%0)" ::"r" (addr) : "memory");
 }
+
+
diff --git a/kernel/x86.h b/kernel/x86.h
index 434c28c..345162f 100644
--- a/kernel/x86.h
+++ b/kernel/x86.h
@@ -18,6 +18,6 @@ void x86_outl(int port, uint32_t data);
 uint32_t x86_inl(int port);
 void x86_set_pdbr(uint32_t addr);
 void x86_paging_enable();
-void x86_flush_tlb(void* m);
+void x86_flush_tlb(uint32_t addr);
 
 #endif