| Stefan Reinauer | 095593c | 2012-12-02 04:49:50 +0000 | [diff] [blame] | 1 | /* |
| 2 | * Copyright (c) 2012 The Chromium OS Authors. |
| 3 | * |
| 4 | * (C) Copyright 2008-2011 |
| 5 | * Graeme Russ, <graeme.russ@gmail.com> |
| 6 | * |
| 7 | * (C) Copyright 2002 |
| 8 | * Daniel Engström, Omicron Ceti AB, <daniel@omicron.se> |
| 9 | * |
| 10 | * Portions of this file are derived from the Linux kernel source |
| 11 | * Copyright (C) 1991, 1992 Linus Torvalds |
| 12 | * |
| 13 | * See file CREDITS for list of people who contributed to this |
| 14 | * project. |
| 15 | * |
| 16 | * This program is free software; you can redistribute it and/or |
| 17 | * modify it under the terms of the GNU General Public License as |
| 18 | * published by the Free Software Foundation; either version 2 of |
| 19 | * the License, or (at your option) any later version. |
| 20 | * |
| 21 | * This program is distributed in the hope that it will be useful, |
| 22 | * but WITHOUT ANY WARRANTY; without even the implied warranty of |
| 23 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
| 24 | * GNU General Public License for more details. |
| 25 | * |
| 26 | * You should have received a copy of the GNU General Public License |
| 27 | * along with this program; if not, write to the Free Software |
| 28 | * Foundation, Inc., 59 Temple Place, Suite 330, Boston, |
| 29 | * MA 02111-1307 USA |
| 30 | */ |
| 31 | |
| 32 | #ifndef __X86_CONTROL_REGS_H |
| 33 | #define __X86_CONTROL_REGS_H |
| 34 | |
| 35 | /* |
| 36 | * The memory clobber prevents the GCC from reordering the read/write order |
| 37 | * of CR0 |
| 38 | */ |
| 39 | static inline unsigned long read_cr0(void) |
| 40 | { |
| 41 | unsigned long val; |
| 42 | |
| 43 | asm volatile ("movl %%cr0, %0" : "=r" (val) : : "memory"); |
| 44 | return val; |
| 45 | } |
| 46 | |
| 47 | static inline void write_cr0(unsigned long val) |
| 48 | { |
| 49 | asm volatile ("movl %0, %%cr0" : : "r" (val) : "memory"); |
| 50 | } |
| 51 | |
| 52 | static inline unsigned long read_cr2(void) |
| 53 | { |
| 54 | unsigned long val; |
| 55 | |
| 56 | asm volatile("mov %%cr2,%0\n\t" : "=r" (val) : : "memory"); |
| 57 | return val; |
| 58 | } |
| 59 | |
| 60 | static inline unsigned long read_cr3(void) |
| 61 | { |
| 62 | unsigned long val; |
| 63 | |
| 64 | asm volatile("mov %%cr3,%0\n\t" : "=r" (val) : : "memory"); |
| 65 | return val; |
| 66 | } |
| 67 | |
| 68 | static inline unsigned long read_cr4(void) |
| 69 | { |
| 70 | unsigned long val; |
| 71 | |
| 72 | asm volatile("mov %%cr4,%0\n\t" : "=r" (val) : : "memory"); |
| 73 | return val; |
| 74 | } |
| 75 | |
| 76 | static inline unsigned long get_debugreg(int regno) |
| 77 | { |
| 78 | unsigned long val = 0; /* Damn you, gcc! */ |
| 79 | |
| 80 | switch (regno) { |
| 81 | case 0: |
| 82 | asm("mov %%db0, %0" : "=r" (val)); |
| 83 | break; |
| 84 | case 1: |
| 85 | asm("mov %%db1, %0" : "=r" (val)); |
| 86 | break; |
| 87 | case 2: |
| 88 | asm("mov %%db2, %0" : "=r" (val)); |
| 89 | break; |
| 90 | case 3: |
| 91 | asm("mov %%db3, %0" : "=r" (val)); |
| 92 | break; |
| 93 | case 6: |
| 94 | asm("mov %%db6, %0" : "=r" (val)); |
| 95 | break; |
| 96 | case 7: |
| 97 | asm("mov %%db7, %0" : "=r" (val)); |
| 98 | break; |
| 99 | default: |
| 100 | val = 0; |
| 101 | } |
| 102 | return val; |
| 103 | } |
| 104 | |
| 105 | #endif |