These changes are the raw update to qemu-2.6.

[kvmfornfv.git] / qemu / roms / ipxe / src / arch / i386 / prefix / libprefix.S

diff --git a/qemu/roms/ipxe/src/arch/i386/prefix/libprefix.S b/qemu/roms/ipxe/src/arch/i386/prefix/libprefix.S
index 7c1ece7..7d5c1ed 100644 (file)
--- a/qemu/roms/ipxe/src/arch/i386/prefix/libprefix.S
+++ b/qemu/roms/ipxe/src/arch/i386/prefix/libprefix.S
@@ -16,9 +16,13 @@
  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
  * 02110-1301, USA.
  *
+ * You can also choose to distribute this program under the terms of
+ * the Unmodified Binary Distribution Licence (as given in the file
+ * COPYING.UBDL), provided that you have satisfied its requirements.
+ *
  */
 
-FILE_LICENCE ( GPL2_OR_LATER )
+FILE_LICENCE ( GPL2_OR_LATER_OR_UBDL )
 
        .arch i386
 
@@ -296,11 +300,9 @@ copy_bytes:
  * Zero bytes
  *
  * Parameters:
- *   %ds:esi : source address
  *   %es:edi : destination address
  *   %ecx : length
  * Returns:
- *   %ds:esi : next source address
  *   %es:edi : next destination address
  * Corrupts:
  *   None
@@ -396,8 +398,10 @@ process_bytes:
        movw    %ax, %fs
        movw    %ax, %gs
 
+#ifdef NDEBUG
        /* Call memcpy()-like function */
        call    *%bx
+#endif
 
        /* Return to (flat) real mode */
        movl    %cr0, %eax
@@ -411,6 +415,20 @@ process_bytes:
        popw    %fs
        popw    %gs
 
+#ifndef NDEBUG
+       /* Call memcpy()-like function in flat real mode (to allow for
+        * debug output via INT 10).
+        */
+       pushw   %ds
+       pushw   %es
+       xorw    %ax, %ax
+       movw    %ax, %ds
+       movw    %ax, %es
+       call    *%bx
+       popw    %es
+       popw    %ds
+#endif
+
        /* Restore GDT */
        data32 lgdt -8(%bp)
        addw    $( 8 /* saved GDT */ + ( PM_DS + 8 ) /* GDT on stack */ ), %sp
@@ -442,11 +460,11 @@ process_bytes:
 
        /* Convert %ds:esi and %es:edi back to physical addresses */
        xorl    %eax, %eax
-       movw    %ds, %cx
+       movw    %ds, %ax
        shll    $4, %eax
        addl    %eax, %esi
        xorl    %eax, %eax
-       movw    %es, %cx
+       movw    %es, %ax
        shll    $4, %eax
        addl    %eax, %edi
 
@@ -678,12 +696,21 @@ install:
        .globl install_prealloc
 install_prealloc:
        progress "install_prealloc:\n"
-       /* Save registers */
+       /* Save registers on external stack */
        pushal
        pushw   %ds
        pushw   %es
        cld                     /* Sanity: clear the direction flag asap */
 
+       /* Switch to temporary stack in .bss16 */
+       pushw   %ss
+       popw    %ds
+       movl    %esp, %ecx
+       movw    %bx, %ss
+       movl    $_data16_memsz, %esp
+       pushw   %ds
+       pushl   %ecx
+
        /* Set up %ds for (read-only) access to .prefix */
        pushw   %cs
        popw    %ds
@@ -710,6 +737,7 @@ install_prealloc:
        popl    %esi
 
 #ifndef KEEP_IT_REAL
+
        /* Access high memory by enabling the A20 gate.  (We will
         * already have 4GB segment limits as a result of calling
         * install_block.)
@@ -778,7 +806,7 @@ payload_death_message:
        movzwl  %bx, %edi
        shll    $4, %edi
        movl    $_data16_filesz, %ecx
-       movl    $_data16_memsz, %edx
+       movl    $_data16_filesz, %edx   /* do not zero our temporary stack */
        call    install_block           /* .data16 */
 
        /* Set up %ds for access to .data16 */
@@ -787,11 +815,8 @@ payload_death_message:
        /* Restore decompression temporary area physical address */
        popl    %edi
 
-#ifdef KEEP_IT_REAL
-       /* Initialise libkir */
-       movw    %ax, (init_libkir_vector+2)
-       lcall   *init_libkir_vector
-#else
+#ifndef KEEP_IT_REAL
+
        /* Find a suitable decompression temporary area, if none specified */
        pushl   %eax
        testl   %edi, %edi
@@ -823,6 +848,22 @@ payload_death_message:
        call    install_block
        popl    %edi
 
+#endif /* KEEP_IT_REAL */
+
+       /* Switch back to original stack and zero .bss16 */
+       addr32 lss %ss:(%esp), %esp
+       pushl   %edi
+       pushw   %es
+       movw    %bx, %es
+       movl    $_data16_filesz, %edi
+       movl    $_data16_memsz, %ecx
+       subl    %edi, %ecx
+       call    zero_bytes
+       popw    %es
+       popl    %edi
+
+#ifndef KEEP_IT_REAL
+
        /* Initialise librm at current location */
        progress "  init_librm\n"
        movw    %ax, (init_librm_vector+2)
@@ -834,7 +875,6 @@ payload_death_message:
        incb    memmap_post
        decl    %ebp
 1:
-
        /* Call relocate() to determine target address for relocation.
         * relocate() will return with %esi, %edi and %ecx set up
         * ready for the copy to the new location.
@@ -857,7 +897,14 @@ payload_death_message:
        /* Initialise librm at new location */
        progress "  init_librm\n"
        lcall   *init_librm_vector
-#endif
+
+#else /* KEEP_IT_REAL */
+
+       /* Initialise libkir */
+       movw    %ax, (init_libkir_vector+2)
+       lcall   *init_libkir_vector
+
+#endif /* KEEP_IT_REAL */
 
        /* Close access to payload */
        progress "  close_payload\n"