From 113c47805cedfb89c80fc4cd60fc22a1c83b96ae Mon Sep 17 00:00:00 2001
From: Timo Kreuzer <timo.kreuzer@reactos.org>
Date: Sun, 5 Sep 2010 16:03:08 +0000
Subject: [PATCH] Update the GAS compatible fathelp.S file to reflect the
 latest changes to the original file (freeldr PE conversion). This version is
 tested and works.

svn path=/trunk/; revision=48701
---
 .../boot/freeldr/freeldr/arch/amd64/fathelp.S | 34 ++++++++-----------
 1 file changed, 15 insertions(+), 19 deletions(-)

diff --git a/reactos/boot/freeldr/freeldr/arch/amd64/fathelp.S b/reactos/boot/freeldr/freeldr/arch/amd64/fathelp.S
index f799cb9978a..8aad29bbfe7 100644
--- a/reactos/boot/freeldr/freeldr/arch/amd64/fathelp.S
+++ b/reactos/boot/freeldr/freeldr/arch/amd64/fathelp.S
@@ -4,10 +4,13 @@
 
 .intel_syntax noprefix
 
+//org 8000h
+
 .text
 
 .code16
 
+
 #define BootSectorStackTop		0x7bf2
 #define DataAreaStartHigh		0x2
 #define DataAreaStartLow		0x4
@@ -38,6 +41,8 @@
 #define VolumeLabel				43
 #define FileSystem				54
 
+#define BootPartition			0x7dfd
+
 
 // This code will be stored in the first 512 bytes
 // of freeldr.sys. The first 3 bytes will be a jmp
@@ -46,7 +51,6 @@
 //
 // This code is loaded at 0000:8000 so we have to
 // encode a jmp instruction to jump to 0000:8200
-//.org 0x8000
 
 .global _mainCRTStartup	// For Mingw32 builds where the linker looks for this symbol
 _mainCRTStartup:
@@ -119,14 +123,14 @@ LoadFile5:
         jmp  LoadFile						// Load the next cluster (if any)
 
 LoadFile_Done:
-        mov  dl, [bp+BootDrive]	// Load the boot drive into DL
-		mov  dh, BootPartition				// Load the boot partition into DH
-        push word ptr 0x0000
-        push word ptr 0x8000					// We will do a far return to 0000:8000h
-
-//        retf								// Transfer control to ROSLDR
-	.byte 0xcb // == retf
+        mov  dl,BYTE PTR [bp+BootDrive]		// Load the boot drive into DL
+		mov  dh,[BootPartition]				// Load the boot partition into DH
 
+		push 0						// push segment (0x0000)
+		mov bx, [0x8000 + 0xA8]		// load the RVA of the EntryPoint into eax
+		add bx, 0x8000				// RVA -> VA and skip 3 bytes (jump to fathelper code)
+		push bx						// push offset
+		retf						// Transfer control to FreeLoader
 
 // Reads the entire FAT into memory at 7000:0000
 ReadFatIntoMemory:
@@ -225,15 +229,7 @@ IsFat12_Done:
 
 
 
-msgLoading:
-		.ascii "Loading FreeLoader..."
-		.byte 0x0d,0x0a,0
-
-//			times 510-($-$$) db 0	// Pad to 510 bytes
-.org 0x1fe
-			.word 0x0aa55				// BootSector signature
-
+msgLoading:	.asciz "Loading FreeLoader...\r\n"
 
-// pseudo adresses
-//.org 0x7dfd
-BootPartition:
+            .org 0x1fe				// Pad to 510 bytes
+			.word 0x0aa55			// BootSector signature
-- 
2.17.1