summary refs log tree commit diff
path: root/sysdeps/standalone/i386/i386.h
diff options
context:
space:
mode:
Diffstat (limited to 'sysdeps/standalone/i386/i386.h')
-rw-r--r--sysdeps/standalone/i386/i386.h327
1 files changed, 327 insertions, 0 deletions
diff --git a/sysdeps/standalone/i386/i386.h b/sysdeps/standalone/i386/i386.h
new file mode 100644
index 0000000000..8302773709
--- /dev/null
+++ b/sysdeps/standalone/i386/i386.h
@@ -0,0 +1,327 @@
+/* Copyright (C) 1994 Free Software Foundation, Inc.
+   Contributed by Joel Sherrill (jsherril@redstone-emh2.army.mil),
+     On-Line Applications Research Corporation.
+ 
+This file is part of the GNU C Library.
+ 
+The GNU C Library is free software; you can redistribute it and/or
+modify it under the terms of the GNU Library General Public License as
+published by the Free Software Foundation; either version 2 of the
+License, or (at your option) any later version.
+ 
+The GNU C Library 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
+Library General Public License for more details.
+ 
+You should have received a copy of the GNU Library General Public
+License along with the GNU C Library; see the file COPYING.LIB.  If
+not, write to the Free Software Foundation, Inc., 675 Mass Ave,
+Cambridge, MA 02139, USA.  */
+
+/*  i386.h
+ *
+ *  This file contains macros which are used to access i80386 
+ *  registers which are not addressable by C.  This file contains
+ *  functions which are useful to those developing target 
+ *  specific support routines.
+ */
+
+#ifndef i386_h__
+#define i386_h__
+
+typedef unsigned char   unsigned8;
+typedef unsigned short  unsigned16;
+typedef unsigned int    unsigned32;
+
+#define disable_intr( isrlevel ) \
+  { (isrlevel) = 0; \
+    asm volatile ( "pushf ; \
+                    pop  %0 ; \
+                    cli   " \
+                    : "=r" ((isrlevel)) : "0" ((isrlevel)) ); \
+  }
+
+
+#define enable_intr( isrlevel ) \
+  { asm volatile ( "push %0 ; \
+                    popf " \
+                    : "=r" ((isrlevel)) : "0" ((isrlevel)) ); \
+  }
+
+#define delay( _microseconds ) \
+  { \
+    unsigned32 _counter; \
+    \
+    _counter = (_microseconds); \
+    \
+    asm volatile ( "0: nop;" \
+                   " mov %0,%0 ;" \
+                   " loop 0" : "=c" (_counter) \
+                                      : "0"  (_counter) \
+                 ); \
+    \
+  }
+
+/* segment access functions */
+
+static inline unsigned16 get_cs()
+{
+  register unsigned16 segment = 0;
+
+  asm volatile ( "movw %%cs,%0" : "=r" (segment) : "0" (segment) ); 
+
+  return segment;
+}
+
+static inline unsigned16 get_ds()
+{
+  register unsigned16 segment = 0;
+
+  asm volatile ( "movw %%ds,%0" : "=r" (segment) : "0" (segment) ); 
+
+  return segment;
+}
+
+static inline unsigned16 get_es()
+{
+  register unsigned16 segment = 0;
+
+  asm volatile ( "movw %%es,%0" : "=r" (segment) : "0" (segment) ); 
+
+  return segment;
+}
+
+static inline unsigned16 get_ss()
+{
+  register unsigned16 segment = 0;
+
+  asm volatile ( "movw %%ss,%0" : "=r" (segment) : "0" (segment) ); 
+
+  return segment;
+}
+
+static inline unsigned16 get_fs()
+{
+  register unsigned16 segment = 0;
+
+  asm volatile ( "movw %%fs,%0" : "=r" (segment) : "0" (segment) ); 
+
+  return segment;
+}
+
+static inline unsigned16 get_gs()
+{
+  register unsigned16 segment = 0;
+
+  asm volatile ( "movw %%gs,%0" : "=r" (segment) : "0" (segment) ); 
+
+  return segment;
+}
+
+/* i80x86 I/O instructions */
+
+#define outport_byte( _port, _value ) \
+   { register unsigned16 __port  = _port; \
+     register unsigned8  __value = _value; \
+     \
+     asm volatile ( "outb %0,%1" : "=a" (__value), "=d" (__port) \
+                                 : "0"   (__value), "1"  (__port) \
+                  ); \
+   }
+
+#define outport_word( _port, _value ) \
+   { register unsigned16 __port  = _port; \
+     register unsigned16 __value = _value; \
+     \
+     asm volatile ( "outw %0,%1" : "=a" (__value), "=d" (__port) \
+                                 : "0"   (__value), "1"  (__port) \
+                  ); \
+   }
+
+#define outport_long( _port, _value ) \
+   { register unsigned16 __port  = _port; \
+     register unsigned32 __value = _value; \
+     \
+     asm volatile ( "outl %0,%1" : "=a" (__value), "=d" (__port) \
+                                 : "0"   (__value), "1"  (__port) \
+                  ); \
+   }
+
+#define inport_byte( _port, _value ) \
+   { register unsigned16 __port  = _port; \
+     register unsigned8  __value = 0; \
+     \
+     asm volatile ( "inb %1,%0" : "=a" (__value), "=d" (__port) \
+                                : "0"   (__value), "1"  (__port) \
+                  ); \
+     _value = __value; \
+   }
+
+#define inport_word( _port, _value ) \
+   { register unsigned16 __port  = _port; \
+     register unsigned16 __value = 0; \
+     \
+     asm volatile ( "inw %1,%0" : "=a" (__value), "=d" (__port) \
+                                : "0"   (__value), "1"  (__port) \
+                  ); \
+     _value = __value; \
+   }
+
+#define inport_long( _port, _value ) \
+   { register unsigned16 __port  = _port; \
+     register unsigned32 __value = 0; \
+     \
+     asm volatile ( "inl %1,%0" : "=a" (__value), "=d" (__port) \
+                                : "0"   (__value), "1"  (__port) \
+                  ); \
+     _value = __value; \
+   }
+
+/* structures */
+
+/* See Chapter 5 - Memory Management in i386 manual */
+
+struct GDT_slot {
+  unsigned16 limit_0_15;
+  unsigned16 base_0_15;
+  unsigned8  base_16_23;
+  unsigned8  type_dt_dpl_p;
+  unsigned8  limit_16_19_granularity;
+  unsigned8  base_24_31;
+};
+
+/* See Chapter 9 - Exceptions and Interrupts in i386 manual 
+ *
+ *  NOTE: This is the IDT entry for interrupt gates ONLY.
+ */
+
+struct IDT_slot {
+  unsigned16 offset_0_15;
+  unsigned16 segment_selector;
+  unsigned8  reserved;
+  unsigned8  p_dpl;
+  unsigned16 offset_16_31;
+};
+
+struct DTR_load_save_format {
+  unsigned16 limit;
+  unsigned32 physical_address;
+};
+
+/* variables */
+
+extern struct IDT_slot Interrupt_descriptor_table[ 256 ];
+extern struct GDT_slot Global_descriptor_table[ 8192 ];
+
+/* functions */
+
+#ifdef CPU_INITIALIZE
+#define EXTERN
+#else
+#undef EXTERN
+#define EXTERN extern
+#endif
+
+void *Logical_to_physical(
+  unsigned16  segment,
+  void             *address
+);
+
+void *Physical_to_logical(
+  unsigned16  segment,
+  void             *address
+);
+
+/* complicated static inline functions */
+
+#define get_GDTR( _gdtr_address ) \
+  { \
+    void                        *_gdtr = (_gdtr_address); \
+    \
+    asm volatile( "sgdt   (%0)" : "=r" (_gdtr) : "0" (_gdtr) ); \
+  }
+
+#define get_GDT_slot( _gdtr_base, _segment, _slot_address ) \
+  { \
+    register unsigned32  _gdt_slot  = (_gdtr_base) + (_segment); \
+    register volatile void    *_slot      = (_slot_address); \
+    register unsigned32  _temporary = 0; \
+    \
+    asm volatile( "movl %%gs:(%0),%1 ; \
+                   movl %1,(%2) ; \
+                   movl %%gs:4(%0),%1 ; \
+                   movl %1,4(%2)"  \
+                     : "=r" (_gdt_slot), "=r" (_temporary), "=r" (_slot) \
+                     : "0"  (_gdt_slot), "1"  (_temporary), "2"  (_slot) \
+                );  \
+  }
+
+#define set_GDT_slot( _gdtr_base, _segment, _slot_address ) \
+  { \
+    register unsigned32  _gdt_slot  = (_gdtr_base) + (_segment); \
+    register volatile void    *_slot      = (_slot_address); \
+    register unsigned32  _temporary = 0; \
+    \
+    asm volatile( "movl (%2),%1 ; \
+                   movl %1,%%gs:(%0) ; \
+                   movl 4(%2),%1 ; \
+                   movl %1,%%gs:4(%0) \
+                  " \
+                     : "=r" (_gdt_slot), "=r" (_temporary), "=r" (_slot) \
+                     : "0"  (_gdt_slot), "1"  (_temporary), "2"  (_slot) \
+                );  \
+  }
+
+static inline void set_segment( 
+  unsigned16 segment, 
+  unsigned32 base,
+  unsigned32 limit 
+) 
+{ 
+  struct DTR_load_save_format  gdtr; 
+  volatile struct GDT_slot     Gdt_slot;
+  volatile struct GDT_slot    *gdt_slot = &Gdt_slot;
+  unsigned16             tmp_segment = 0;
+  unsigned32             limit_adjusted;
+ 
+  
+  /* load physical address of the GDT */
+
+  get_GDTR( &gdtr );
+ 
+  gdt_slot->type_dt_dpl_p  = 0x92;             /* present, dpl=0,      */
+                                               /* application=1,       */
+                                               /* type=data read/write */
+  gdt_slot->limit_16_19_granularity = 0x40;    /* 32 bit segment       */
+
+  limit_adjusted = limit;
+  if ( limit > 4095 ) {
+    gdt_slot->limit_16_19_granularity |= 0x80; /* set granularity bit */
+    limit_adjusted /= 4096;
+  } 
+ 
+  gdt_slot->limit_16_19_granularity |= (limit_adjusted >> 16) & 0xff;
+  gdt_slot->limit_0_15               = limit_adjusted & 0xffff;
+ 
+  gdt_slot->base_0_15  = base & 0xffff;
+  gdt_slot->base_16_23 = (base >> 16) & 0xff;
+  gdt_slot->base_24_31 = (base >> 24);
+ 
+  set_GDT_slot( gdtr.physical_address, segment, gdt_slot );
+
+  /* Now, reload all segment registers so the limit takes effect. */
+
+  asm volatile( "movw %%ds,%0 ; movw %0,%%ds
+                 movw %%es,%0 ; movw %0,%%es
+                 movw %%fs,%0 ; movw %0,%%fs
+                 movw %%gs,%0 ; movw %0,%%gs
+                 movw %%ss,%0 ; movw %0,%%ss"
+                   : "=r" (tmp_segment) 
+                   : "0"  (tmp_segment)
+              );
+                 
+}
+
+#endif
+/* end of include file */