/* Copyright (C) 2008  Emmanuel Varoquaux

   This file is part of XOS.

   This program is free software: you can redistribute it and/or modify
   it under the terms of the GNU General Public License as published by
   the Free Software Foundation, either version 3 of the License, or
   (at your option) any later version.

   This program 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 General Public License for more details.

   You should have received a copy of the GNU General Public License
   along with this program.  If not, see <http://www.gnu.org/licenses/>. */

#ifndef _ASM_H
#define _ASM_H

/* instructions diverses */

#define nop()           asm volatile ("nop")

/* registres de segment */

#define load_cs(sel) \
asm volatile ("ljmpl %0, $1f\n" \
              "1:" \
              :: "i" (sel))

#define load_ds(sel) \
asm volatile ("movw %w0, %%ds" :: "r" (sel) : "memory")

#define load_es(sel) \
asm volatile ("movw %w0, %%es" :: "r" (sel) : "memory")

#define load_fs(sel) \
asm volatile ("movw %w0, %%fs" :: "r" (sel) : "memory")

#define load_gs(sel) \
asm volatile ("movw %w0, %%gs" :: "r" (sel) : "memory")

#define load_ss(sel) \
asm volatile ("movw %w0, %%ss" :: "r" (sel) : "memory")

#define get_fs(fs) \
asm ("movw %%fs, %0" : "=r" (fs))

/* tables de descripteurs */

#define lldt(sel)       asm volatile ("lldt %w0" :: "r" (sel))
#define lgdt(descr)     asm volatile ("lgdt %0" :: "m" (descr))

/* multitache */

#define ltr(sel)        asm volatile ("ltr %w0" :: "r" (sel))

/* controle des interruptions */

#define cli()           asm volatile ("cli")
#define sti()           asm volatile ("sti")
#define lidt(descr)     asm volatile ("lidt %0" :: "m" (descr))

#define disable_intr(intr) \
asm volatile ("pushfl\n\t" \
              "popl %0\n\t" \
              "andl $0x200, %0\n\t" \
              "cli" \
              : "=r" (intr) \
              :: "memory")

#define restore_intr(intr) \
asm volatile ("testl %0, %0\n\t" \
              "jz 1f\n\t" \
              "sti\n" \
              "1:" \
              :: "r" (intr) \
              : "cc")

/* entrees/sorties */

#define outb(value, port) \
asm volatile ("outb %%al, %%dx" :: "a" (value), "d" (port))

#define outbp(value, port) \
asm volatile ("outb %%al, %%dx\n\t" \
              "jmp 1f\n" \
              "1:" :: "a" (value), "d" (port))

#define inb(port) ({ \
  unsigned char _v; \
  asm volatile ("inb %%dx, %%al" : "=a" (_v) : "d" (port)); \
  _v; \
})

#define inbp(port) ({ \
  unsigned char _v; \
  asm volatile ("inb %%dx, %%al\n\t" \
                "jmp 1f\n" \
                "1:" : "=a" (_v) : "d" (port)); \
  _v; \
})

/* controle du systeme */

#define hlt()           asm volatile ("hlt")

/* registres de controle */

#define save_control_flags(flags) \
asm ("movl %%cr0, %0" : "=r" (flags))

#define restore_control_flags(flags) \
asm volatile ("movl %0, %%cr0" :: "r" (flags))

#define disable_cache() \
asm volatile ("movl %%cr0, %%eax\n\t" \
              "orl $0x40000000, %%eax\n\t" \
              "movl %%eax, %%cr0\n\t" \
              "wbinvd\n\t" \
              "orl $0x20000000, %%eax\n\t" \
              "movl %%eax, %%cr0" \
              ::: "%eax")

#define set_pg() \
asm volatile ("movl %%cr0, %%eax\n\t" \
              "orl $0x80000000, %%eax\n\t" \
              "movl %%eax, %%cr0\n\t" \
              "jmp 1f\n" \
              "1:" \
              ::: "%eax", "memory")

#define get_page_fault_laddr(laddr) \
asm ("movl %%cr2, %0" : "=r" (laddr))

#define get_pdbr(pdbr) \
asm ("movl %%cr3, %0" : "=r" (pdbr))

#define set_pdbr(pdbr) \
asm volatile ("movl %0, %%cr3" :: "r" (pdbr) : "memory")

/* commutation de taches */

#define task_switch(addr) \
asm volatile ("ljmpl *%0" :: "m" (addr) : "memory")

/* instructions speciales */

#define invlpg(laddr) \
asm volatile ("invlpg %0" :: "m" (*(char *)laddr) : "memory");

#endif