[Qemu-devel] [PATCH v2 4/6] Execute rombios32 code from rom address 0xe0000.

[Gleb Natapov <gleb@redhat.com>]

Signed-off-by: Gleb Natapov <gleb@redhat.com>
---

 bios/Makefile.in      |    1 +
 bios/rombios.c        |   17 +----------------
 bios/rombios32.ld     |    8 +++-----
 bios/rombios32start.S |    9 ++++++++-
 4 files changed, 13 insertions(+), 22 deletions(-)

diff --git a/bios/Makefile.in b/bios/Makefile.in
index b055910..af674b4 100644
--- a/bios/Makefile.in
+++ b/bios/Makefile.in
@@ -106,6 +106,7 @@ rombios32.o: rombios32.c acpi-dsdt.hex
 ifeq ("1", "0")
 acpi-dsdt.hex: acpi-dsdt.dsl
 	iasl -tc -p $@ $<
+	sed -i -e's/^unsigned/const unsigned/' $@
 endif
 
 rombios32start.o: rombios32start.S
diff --git a/bios/rombios.c b/bios/rombios.c
index 03540cb..098543c 100644
--- a/bios/rombios.c
+++ b/bios/rombios.c
@@ -10026,13 +10026,6 @@ rombios32_05:
   mov gs, ax
   cld
 
-  ;; copy rombios32 code to ram (ram offset = 1MB)
-  mov esi, #0xfffe0000
-  mov edi, #0x00040000
-  mov ecx, #0x10000 / 4
-  rep
-    movsd
-
   ;; init the stack pointer
   mov esp, #0x00080000
 
@@ -10041,17 +10034,9 @@ rombios32_05:
   push #0x04b2
 
   ;; call rombios32 code
-  mov eax, #0x00040000
+  mov eax, #0x000e0000
   call eax
 
-  ;; reset the memory (some boot loaders such as syslinux suppose
-  ;; that the memory is set to zero)
-  mov edi, #0x00040000
-  mov ecx, #0x40000 / 4
-  xor eax, eax
-  rep
-    stosd
-
   ;; return to 16 bit protected mode first
   db 0xea
   dd rombios32_10
diff --git a/bios/rombios32.ld b/bios/rombios32.ld
index c7f6066..113a2c0 100644
--- a/bios/rombios32.ld
+++ b/bios/rombios32.ld
@@ -3,14 +3,12 @@ OUTPUT_ARCH(i386)
 ENTRY(_start);
 SECTIONS
 {
-        . = 0x00040000;
+        . = 0x000e0000;
         .text     : { *(.text)    }
         .rodata    : { *(.rodata) }
-        . = ALIGN(4096);
-        .data     : { *(.data)    }
-        __bss_start = . ;
-        .bss      : { *(.bss) *(COMMON) }
         _end = . ;
+        .data 0x700 : AT (_end) { __data_start = .; *(.data); __data_end = .;}
+        .bss      : { __bss_start = .; *(.bss) *(COMMON); __bss_end = .;}
         /DISCARD/ : { *(.stab)
                      *(.stabstr)
                      *(.comment)
diff --git a/bios/rombios32start.S b/bios/rombios32start.S
index 601e2b0..1900261 100644
--- a/bios/rombios32start.S
+++ b/bios/rombios32start.S
@@ -32,10 +32,17 @@ _start:
   /* clear bss section */
   xor %eax, %eax
   mov $__bss_start, %edi
-  mov $_end, %ecx
+  mov $__bss_end, %ecx
   sub %edi, %ecx
   rep stosb
 
+  /* copy data section */
+  mov $_end, %esi
+  mov $__data_start, %edi
+  mov $__data_end, %ecx
+  sub %edi, %ecx
+  rep movsb
+
   jmp rombios32_init
 
   .code16