[ros-diffs] [tkreuzer] 52221: [FREELDR] Start moving the 16 bit code into the raw binary chunk. We now switch to protected mode before jumping to the PE entry point

Author: tkreuzer
Date: Mon Jun 13 20:03:55 2011
New Revision: 52221
URL: http://svn.reactos.org/svn/reactos?rev=52221&view=rev
Log:
[FREELDR]
Start moving the 16 bit code into the raw binary chunk.
We now switch to protected mode before jumping to the PE entry point
Added:
    trunk/reactos/boot/freeldr/freeldr/arch/i386/entry.S
      - copied, changed from r52207, trunk/reactos/boot/freeldr/freeldr/arch/i386/arch.S
Modified:
    trunk/reactos/boot/freeldr/freeldr/CMakeLists.txt
    trunk/reactos/boot/freeldr/freeldr/arch/realmode/i386.S
    trunk/reactos/boot/freeldr/freeldr/include/arch/pc/x86common.h
Modified: trunk/reactos/boot/freeldr/freeldr/CMakeLists.txt
URL:
http://svn.reactos.org/svn/reactos/trunk/reactos/boot/freeldr/freeldr/CMake…
==============================================================================
--- trunk/reactos/boot/freeldr/freeldr/CMakeLists.txt [iso-8859-1] (original)
+++ trunk/reactos/boot/freeldr/freeldr/CMakeLists.txt [iso-8859-1] Mon Jun 13 20:03:55
2011
@@ -9,26 +9,9 @@
 endif()
 if(ARCH MATCHES i386)
-    if(MSVC)
-        list(APPEND FREELDR_BASE64K_SOURCE
-            arch/i386/realmode.S)
-    else()
-        list(APPEND FREELDR_STARTUP_SOURCE
-            arch/i386/arch.S)
-    endif()
-elseif(ARCH MATCHES amd64)
-    if(MSVC)
-        list(APPEND FREELDR_BASE64K_SOURCE
-            arch/amd64/stubs.S)
-    else()
-        list(APPEND FREELDR_STARTUP_SOURCE
-            arch/amd64/arch.S)
-    endif()
-endif()
-
-if(ARCH MATCHES i386)
     if(NOT MSVC)
         list(APPEND FREELDR_BASE64K_SOURCE
+            arch/i386/entry.S
             arch/i386/boot.S
             arch/i386/drvmap.S
             arch/i386/i386cpu.S
@@ -40,15 +23,21 @@
             arch/i386/linux.S
             arch/i386/mb.S
             arch/i386/i386bug.c)
+    else()
+        list(APPEND FREELDR_BASE64K_SOURCE
+            arch/i386/realmode.S)
     endif()
 elseif(ARCH MATCHES amd64)
     if(NOT MSVC)
-    list(APPEND FREELDR_BASE64K_SOURCE
-        arch/i386/drvmap.S
-        arch/i386/i386cpu.S
-        arch/i386/i386idt.S
-        arch/i386/i386trap.S
-        arch/amd64/mb.S)
+        list(APPEND FREELDR_BASE64K_SOURCE
+            arch/i386/drvmap.S
+            arch/i386/i386cpu.S
+            arch/i386/i386idt.S
+            arch/i386/i386trap.S
+            arch/amd64/mb.S)
+    else()
+        list(APPEND FREELDR_BASE64K_SOURCE
+            arch/amd64/stubs.S)
     endif()
 endif()
@@ -187,7 +176,6 @@
 list(APPEND FREELDR_SOURCE
     bootmgr.c
-    ${FREELDR_STARTUP_SOURCE}
     ${FREELDR_BASE64K_SOURCE}
     ${FREELDR_BASE_SOURCE}
     )
@@ -242,7 +230,6 @@
 endif()
 list(APPEND SETUPLDR_SOURCE
-    ${FREELDR_STARTUP_SOURCE}
     ${FREELDR_BASE64K_SOURCE}
     ${FREELDR_BASE_SOURCE}
     ${SETUPLDR_MAIN_SOURCE})
Copied: trunk/reactos/boot/freeldr/freeldr/arch/i386/entry.S (from r52207,
trunk/reactos/boot/freeldr/freeldr/arch/i386/arch.S)
URL:
http://svn.reactos.org/svn/reactos/trunk/reactos/boot/freeldr/freeldr/arch/…
==============================================================================
--- trunk/reactos/boot/freeldr/freeldr/arch/i386/arch.S [iso-8859-1] (original)
+++ trunk/reactos/boot/freeldr/freeldr/arch/i386/entry.S [iso-8859-1] Mon Jun 13 20:03:55
2011
@@ -20,52 +20,49 @@
 .intel_syntax noprefix
 #define HEX(y) 0x##y
+#include <asm.inc>
 #include <arch/pc/x86common.h>
 #include <multiboot.h>
-       .code16
-
-EXTERN(_RealEntryPoint)
-
-       cli
-
-       /* Setup segment registers */
-       xor ax, ax
+.code32
+
+PUBLIC _RealEntryPoint
+_RealEntryPoint:
+
+       /* Setup segment selectors */
+       mov ax, PMODE_DS
        mov ds, ax
        mov es, ax
        mov fs, ax
        mov gs, ax
        mov ss, ax
-       /* Setup a stack */
-       mov sp, word ptr ds:stack16
-
-       sti
-
-       /* Init pmode */
-       call    switch_to_prot
-
-       .code32
-
-       /* Zero BootDrive and BootPartition */
+    /* Setup protected mode stack */
+       mov esp, dword ptr [stack32]
+
+       /* Load the IDT */
+       lidt i386idtptr
+
+    /* Continue execution */
+    jmp dword ptr [_ContinueAddress]
+
+_ContinueAddress:
+    .long _FrldrStartup
+
+
+_FrldrStartup:
+
+    /* Store BootDrive and BootPartition */
+    xor eax, eax
+    mov al, dl
+       mov dword ptr [_FrldrBootDrive], eax
+    mov al, dh
+       mov dword ptr [_FrldrBootPartition], eax
+
+       /* GO! */
        xor eax, eax
-       mov dword ptr [_FrldrBootDrive], eax
-       mov dword ptr [_FrldrBootPartition], eax
-
-       /* Store the boot drive */
-       mov byte ptr [_FrldrBootDrive], dl
-
-       /* Store the boot partition */
-       mov byte ptr [_FrldrBootPartition], dh
-
-       /* GO! */
        push eax
-       call    _BootMain
-
-       call    switch_to_real
-       .code16
-
-       int HEX(19)
+       call _BootMain
        /* We should never get here */
 stop:
@@ -399,12 +396,12 @@
        mov eax, [ebx + MB_INFO_BOOT_DEVICE_OFFSET]
        shr eax, 16
        inc al
-       mov byte ptr _FrldrBootPartition, al
-       mov byte ptr _FrldrBootDrive, ah
+       mov byte ptr [_FrldrBootPartition], al
+       mov byte ptr [_FrldrBootDrive], ah
        jmp mb6
 mb5:   /* No boot device known, assume first partition of first harddisk */
-       mov byte ptr _FrldrBootDrive, HEX(80)
-       mov byte ptr _FrldrBootPartition, 1
+       mov byte ptr [_FrldrBootDrive], HEX(80)
+       mov byte ptr [_FrldrBootPartition], 1
 mb6:
        /* Check for command line */
        mov eax, offset cmdline
@@ -495,8 +492,12 @@
 cmdline:
        .fill   CMDLINE_SIZE, 1, 0
-EXTERN(_FrldrBootDrive)
+PUBLIC _FrldrBootDrive
+_FrldrBootDrive:
     .long 0
-EXTERN(_FrldrBootPartition)
+PUBLIC _FrldrBootPartition
+_FrldrBootPartition:
     .long 0
+
+END
Modified: trunk/reactos/boot/freeldr/freeldr/arch/realmode/i386.S
URL:
http://svn.reactos.org/svn/reactos/trunk/reactos/boot/freeldr/freeldr/arch/…
==============================================================================
--- trunk/reactos/boot/freeldr/freeldr/arch/realmode/i386.S [iso-8859-1] (original)
+++ trunk/reactos/boot/freeldr/freeldr/arch/realmode/i386.S [iso-8859-1] Mon Jun 13
20:03:55 2011
@@ -12,17 +12,101 @@
 #include "fathelp.inc"
 .org 512
-RealEntryPoint:
+RealModeEntryPoint:
+
+    cli
+
+    /* Setup segment registers */
+    xor ax, ax
+    mov ds, ax
+    mov es, ax
+    mov fs, ax
+    mov gs, ax
+    mov ss, ax
+
+    /* Setup the stack */
+    mov sp, word ptr ds:stack16
     /* Get address of optional header */
     mov eax, dword ptr ds:[FREELDR_PE_BASE + IMAGE_DOS_HEADER_e_lfanew]
     add eax, FREELDR_PE_BASE + 4 + IMAGE_FILE_HEADER_SIZE
-    /* Jump to address of entry point */
+    /* Get address of entry point */
     mov eax, dword ptr ds:[eax + IMAGE_OPTIONAL_HEADER_AddressOfEntryPoint]
     add eax, FREELDR_PE_BASE
-    jmp ax
+    /* Safe the entry point */
+    mov dword ptr [BSS_EntryPoint], eax
+
+    /* Patch the long jump instruction */
+    mov word ptr [pm_offset], ax
+
+/*
+ * Switches the processor to protected mode
+ * it destroys eax
+ */
+switch_to_prot:
+
+    /* Load the GDT */
+    lgdt    gdtptr
+
+    /* Enable Protected Mode */
+    mov eax, cr0
+    or eax, CR0_PE_SET
+    mov cr0, eax
+
+    /* Clear prefetch queue & correct CS */
+    .byte HEX(0ea) // jmp far PMODE_CS:entry_point
+pm_offset:
+    .word 0 // receives address of PE entry point
+    .word PMODE_CS
+    nop
+
+
+
+    /* 16-bit stack pointer */
+stack16:
+    .word    STACK16ADDR
+
+
+.align 4       /* force 4-byte alignment */
+gdt:
+       /* NULL Descriptor */
+       .word HEX(0000)
+       .word HEX(0000)
+       .word HEX(0000)
+       .word HEX(0000)
+
+       /* 32-bit flat CS */
+       .word HEX(FFFF)
+       .word HEX(0000)
+       .word HEX(9A00)
+       .word HEX(00CF)
+
+       /* 32-bit flat DS */
+       .word HEX(FFFF)
+       .word HEX(0000)
+       .word HEX(9200)
+       .word HEX(00CF)
+
+       /* 16-bit real mode CS */
+       .word HEX(FFFF)
+       .word HEX(0000)
+       .word HEX(9E00)
+       .word HEX(0000)
+
+       /* 16-bit real mode DS */
+       .word HEX(FFFF)
+       .word HEX(0000)
+       .word HEX(9200)
+       .word HEX(0000)
+
+/* GDT table pointer */
+gdtptr:
+       .word HEX(27)           /* Limit */
+       .long gdt                       /* Base Address */
+
+.org 1024
 #include "helpers.inc"
Modified: trunk/reactos/boot/freeldr/freeldr/include/arch/pc/x86common.h
URL:
http://svn.reactos.org/svn/reactos/trunk/reactos/boot/freeldr/freeldr/inclu…
==============================================================================
--- trunk/reactos/boot/freeldr/freeldr/include/arch/pc/x86common.h [iso-8859-1] (original)
+++ trunk/reactos/boot/freeldr/freeldr/include/arch/pc/x86common.h [iso-8859-1] Mon Jun 13
20:03:55 2011
@@ -4,8 +4,8 @@
 #endif
 /* Memory layout */
-#define STACK16ADDR         HEX(7000) /* The 16-bit stack top will be at 0000:7000 */
-#define BSS_START           HEX(7000)
+#define STACK16ADDR         HEX(6F00) /* The 16-bit stack top will be at 0000:6F00 */
+#define BSS_START           HEX(6F00)
 #define FREELDR_BASE        HEX(8000)
 #define FREELDR_PE_BASE     HEX(9000)
 #define STACK32ADDR        HEX(78000) /* The 32-bit stack top will be at 7000:8000, or
0x78000 */
@@ -17,15 +17,12 @@
 #define DISKREADBUFFER_SIZE 512
 /* These addresses specify the realmode "BSS section" layout */
-#define BSS_CallbackAddress BSS_START + 0
-#define BSS_CallbackReturn BSS_START + 8
-#define BSS_BootDrive BSS_START + 16
-#define BSS_BootPartition BSS_START + 20
+#define BSS_EntryPoint      (BSS_START +  0)
+#define BSS_CallbackAddress (BSS_START +  4)
+#define BSS_CallbackReturn  (BSS_START +  8)
+#define BSS_BootDrive       (BSS_START + 12)
+#define BSS_BootPartition   (BSS_START + 16)
-#ifdef _M_AMD64
-#define FrldrBootDrive *((PULONG)BSS_BootDrive)
-#define FrldrBootPartition *((PULONG)BSS_BootPartition)
-#endif
 // Flag Masks
 #define I386FLAG_CF            HEX(0001)  // Carry Flag
@@ -45,13 +42,13 @@
 #define CR0_PE_CLR     HEX(FFFFFFFE)   /* AND this value with CR0 to disable pmode */
 /* Defines needed for switching between real and protected mode */
-#ifdef _M_IX86
+//#ifdef _M_IX86
 #define NULL_DESC      HEX(00) /* NULL descriptor */
 #define PMODE_CS       HEX(08) /* PMode code selector, base 0 limit 4g */
 #define PMODE_DS       HEX(10) /* PMode data selector, base 0 limit 4g */
 #define RMODE_CS       HEX(18) /* RMode code selector, base 0 limit 64k */
 #define RMODE_DS       HEX(20) /* RMode data selector, base 0 limit 64k */
-#endif
+//#endif
 /* Makes "x" a global variable or label */
 #define EXTERN(x)      .global x; x: