diff options
Diffstat (limited to 'sysdeps/standalone/i386/i386.h')
| -rw-r--r-- | sysdeps/standalone/i386/i386.h | 327 |
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 */ |