diff options
Diffstat (limited to 'newlib/libc/sys/go32/dosmem.S')
| -rw-r--r-- | newlib/libc/sys/go32/dosmem.S | 120 |
1 files changed, 120 insertions, 0 deletions
diff --git a/newlib/libc/sys/go32/dosmem.S b/newlib/libc/sys/go32/dosmem.S new file mode 100644 index 00000000000..c1956f76781 --- /dev/null +++ b/newlib/libc/sys/go32/dosmem.S @@ -0,0 +1,120 @@ +/* DOSMEM.S */ +/* +** Copyright (C) 1993 C.W. Sandmann +** +** This file may be freely distributed as long as the author's name remains. +** Extender environment independent way to set up Real area 1Mb access. +** Procedure takes a single argument %eax which contains the real area offset. +** After call, access may be made with "%gs:(%eax)" +*/ + .text + .align 2 + .globl dosmemsetup +dosmemsetup: /* no params, expected ASM call only */ + pushl %eax + movzwl __core_select,%eax + testl %eax,%eax + je old_go32 /* Image run with pre-DPMI extender */ + movw %ax,%gs /* Use real area selector */ + popl %eax /* Plus real offset */ + andl $0x0fffffff,%eax /* Clear any linear access bits */ + ret + .align 2,0x90 +old_go32: + push %ds + pop %gs /* Use arena selector */ + popl %eax + orl $0xe0000000,%eax /* Plus linear access area */ + ret + + .align 2 + .globl _dosmemget +_dosmemget: /* long offset, long len, long *buf */ + push %gs + movl 8(%esp),%eax /* offset */ + call dosmemsetup + movl 12(%esp),%ecx /* length */ + movl 16(%esp),%edx /* arena offset */ + pushl %esi + pushl %edi + movl %eax,%esi + movl %edx,%edi + push %ds + push %es + push %ds + pop %es + push %gs + pop %ds + cld + rep + movsb /* move ECX bytes from Real area */ + pop %es + pop %ds + popl %edi + popl %esi + pop %gs + ret + + .align 2 + .globl _dosmemput +_dosmemput: /* long *buf, long len, long offset */ + push %gs + movl 16(%esp),%eax /* offset */ + call dosmemsetup + movl 12(%esp),%ecx /* length */ + movl 8(%esp),%edx /* arena offset */ + pushl %esi + pushl %edi + movl %eax,%edi + movl %edx,%esi + push %es + push %gs + pop %es + cld + rep + movsb /* move ECX bytes to Real area */ + pop %es + popl %edi + popl %esi + pop %gs + ret + + .align 2 /* 8(bp) 12(bp) 16(bp) 20(bp) 24(bp) */ + .globl _movedata /* src_sel, src_ofs, dest_sel, dest_ofs, len */ +_movedata: + pushl %ebp + movl %esp,%ebp + pushw %ds + pushw %es + pushl %esi + pushl %edi + + movl 8(%ebp),%eax + movw %ax,%ds + movl 12(%ebp),%esi + + movl 16(%ebp),%eax + movw %ax,%es + movl 20(%ebp),%edi + + movl 24(%ebp),%ecx + pushl %ecx + shrl $2,%ecx + jcxz no_big_move + rep + movsl +no_big_move: + popl %ecx + andl $3,%ecx + jcxz no_little_move + rep + movsb +no_little_move: + + popl %edi + popl %esi + popw %es + popw %ds + leave + ret + |