VGA softbootloader for Linux, uses an x86 CPU emulator on non x86 arches.

1 files changed, 135 insertions, 0 deletions

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