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Diffstat (limited to 'contrib/syslinux-4.02/gpxe/src/arch/i386/interface/syslinux/com32_wrapper.S')
-rw-r--r--contrib/syslinux-4.02/gpxe/src/arch/i386/interface/syslinux/com32_wrapper.S94
1 files changed, 94 insertions, 0 deletions
diff --git a/contrib/syslinux-4.02/gpxe/src/arch/i386/interface/syslinux/com32_wrapper.S b/contrib/syslinux-4.02/gpxe/src/arch/i386/interface/syslinux/com32_wrapper.S
new file mode 100644
index 0000000..5c5bd13
--- /dev/null
+++ b/contrib/syslinux-4.02/gpxe/src/arch/i386/interface/syslinux/com32_wrapper.S
@@ -0,0 +1,94 @@
+/*
+ * Copyright (C) 2008 Daniel Verkamp <daniel@drv.nu>.
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License as
+ * published by the Free Software Foundation; either version 2 of the
+ * License, or any later version.
+ *
+ * This program is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ * General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
+ */
+
+FILE_LICENCE ( GPL2_OR_LATER )
+
+ .text
+ .arch i386
+ .code32
+
+ .globl com32_farcall_wrapper
+com32_farcall_wrapper:
+
+ movl $com32_farcall, %eax
+ jmp com32_wrapper
+
+
+ .globl com32_cfarcall_wrapper
+com32_cfarcall_wrapper:
+
+ movl $com32_cfarcall, %eax
+ jmp com32_wrapper
+
+
+ .globl com32_intcall_wrapper
+com32_intcall_wrapper:
+
+ movl $com32_intcall, %eax
+ /*jmp com32_wrapper*/ /* fall through */
+
+com32_wrapper:
+
+ /* Switch to internal virtual address space */
+ call _phys_to_virt
+
+ mov %eax, (com32_helper_function)
+
+ /* Save external COM32 stack pointer */
+ movl %esp, (com32_external_esp)
+
+ /* Copy arguments to caller-save registers */
+ movl 12(%esp), %eax
+ movl 8(%esp), %ecx
+ movl 4(%esp), %edx
+
+ /* Switch to internal stack */
+ movl (com32_internal_esp), %esp
+
+ /* Copy arguments to internal stack */
+ pushl %eax
+ pushl %ecx
+ pushl %edx
+
+ call *(com32_helper_function)
+
+ /* Clean up stack */
+ addl $12, %esp
+
+ /* Save internal stack pointer and restore external stack pointer */
+ movl %esp, (com32_internal_esp)
+ movl (com32_external_esp), %esp
+
+ /* Switch to external flat physical address space */
+ call _virt_to_phys
+
+ ret
+
+
+ .data
+
+/* Internal gPXE virtual address space %esp */
+.globl com32_internal_esp
+.lcomm com32_internal_esp, 4
+
+/* External flat physical address space %esp */
+.globl com32_external_esp
+.lcomm com32_external_esp, 4
+
+/* Function pointer of helper to call */
+.lcomm com32_helper_function, 4