[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/CMakeL... ============================================================================== --- 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/i... ============================================================================== --- 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/r... ============================================================================== --- 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/includ... ============================================================================== --- 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:
-
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