From e0fbcfe868b509f256fcdc239178d32f617bb129 Mon Sep 17 00:00:00 2001 From: =?UTF-8?q?Gwenol=C3=A9=20Beauchesne?= Date: Wed, 25 Aug 2004 05:45:29 +0000 Subject: VGA softbootloader for Linux, uses an x86 CPU emulator on non x86 arches. --- tools/ddcprobe/int10/vm86_struct.h | 135 +++++++++++++++++++++++++++++++++++++ 1 file changed, 135 insertions(+) create mode 100644 tools/ddcprobe/int10/vm86_struct.h (limited to 'tools/ddcprobe/int10/vm86_struct.h') diff --git a/tools/ddcprobe/int10/vm86_struct.h b/tools/ddcprobe/int10/vm86_struct.h new file mode 100644 index 000000000..772e6cab2 --- /dev/null +++ b/tools/ddcprobe/int10/vm86_struct.h @@ -0,0 +1,135 @@ +#ifndef _LINUX_VM86_H +#define _LINUX_VM86_H + +/* + * I'm guessing at the VIF/VIP flag usage, but hope that this is how + * the Pentium uses them. Linux will return from vm86 mode when both + * VIF and VIP is set. + * + * On a Pentium, we could probably optimize the virtual flags directly + * in the eflags register instead of doing it "by hand" in vflags... + * + * Linus + */ + +#define TF_MASK 0x00000100 +#define IF_MASK 0x00000200 +#define IOPL_MASK 0x00003000 +#define NT_MASK 0x00004000 +#define VM_MASK 0x00020000 +#define AC_MASK 0x00040000 +#define VIF_MASK 0x00080000 /* virtual interrupt flag */ +#define VIP_MASK 0x00100000 /* virtual interrupt pending */ +#define ID_MASK 0x00200000 + +#define BIOSSEG 0x0f000 + +#define CPU_086 0 +#define CPU_186 1 +#define CPU_286 2 +#define CPU_386 3 +#define CPU_486 4 +#define CPU_586 5 + +/* + * Return values for the 'vm86()' system call + */ +#define VM86_TYPE(retval) ((retval) & 0xff) +#define VM86_ARG(retval) ((retval) >> 8) + +#define VM86_SIGNAL 0 /* return due to signal */ +#define VM86_UNKNOWN 1 /* unhandled GP fault - IO-instruction or similar */ +#define VM86_INTx 2 /* int3/int x instruction (ARG = x) */ +#define VM86_STI 3 /* sti/popf/iret instruction enabled virtual interrupts */ + +/* + * Additional return values when invoking new vm86() + */ +#define VM86_PICRETURN 4 /* return due to pending PIC request */ +#define VM86_TRAP 6 /* return due to DOS-debugger request */ + +/* + * function codes when invoking new vm86() + */ +#define VM86_PLUS_INSTALL_CHECK 0 +#define VM86_ENTER 1 +#define VM86_ENTER_NO_BYPASS 2 +#define VM86_REQUEST_IRQ 3 +#define VM86_FREE_IRQ 4 +#define VM86_GET_IRQ_BITS 5 +#define VM86_GET_AND_RESET_IRQ 6 + +/* + * This is the stack-layout seen by the user space program when we have + * done a translation of "SAVE_ALL" from vm86 mode. The real kernel layout + * is 'kernel_vm86_regs' (see below). + */ + +struct vm86_regs { +/* + * normal regs, with special meaning for the segment descriptors.. + */ + long ebx; + long ecx; + long edx; + long esi; + long edi; + long ebp; + long eax; + long __null_ds; + long __null_es; + long __null_fs; + long __null_gs; + long orig_eax; + long eip; + unsigned short cs, __csh; + long eflags; + long esp; + unsigned short ss, __ssh; +/* + * these are specific to v86 mode: + */ + unsigned short es, __esh; + unsigned short ds, __dsh; + unsigned short fs, __fsh; + unsigned short gs, __gsh; +}; + +struct revectored_struct { + unsigned long __map[8]; /* 256 bits */ +}; + +struct vm86_struct { + struct vm86_regs regs; + unsigned long flags; + unsigned long screen_bitmap; + unsigned long cpu_type; + struct revectored_struct int_revectored; + struct revectored_struct int21_revectored; +}; + +/* + * flags masks + */ +#define VM86_SCREEN_BITMAP 0x0001 + +struct vm86plus_info_struct { + unsigned long force_return_for_pic:1; + unsigned long vm86dbg_active:1; /* for debugger */ + unsigned long vm86dbg_TFpendig:1; /* for debugger */ + unsigned long unused:28; + unsigned long is_vm86pus:1; /* for vm86 internal use */ + unsigned char vm86dbg_intxxtab[32]; /* for debugger */ +}; + +struct vm86plus_struct { + struct vm86_regs regs; + unsigned long flags; + unsigned long screen_bitmap; + unsigned long cpu_type; + struct revectored_struct int_revectored; + struct revectored_struct int21_revectored; + struct vm86plus_info_struct vm86plus; +}; + +#endif -- cgit v1.2.1