payloads/libpayload/include/x86/arch/msr.h

   1 /*
   2  *
   3  * Copyright (C) 2008 Advanced Micro Devices, Inc.
   4  *
   5  * Redistribution and use in source and binary forms, with or without
   6  * modification, are permitted provided that the following conditions
   7  * are met:
   8  * 1. Redistributions of source code must retain the above copyright
   9  *    notice, this list of conditions and the following disclaimer.
  10  * 2. Redistributions in binary form must reproduce the above copyright
  11  *    notice, this list of conditions and the following disclaimer in the
  12  *    documentation and/or other materials provided with the distribution.
  13  * 3. The name of the author may not be used to endorse or promote products
  14  *    derived from this software without specific prior written permission.
  15  *
  16  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
  17  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  18  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  19  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
  20  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  21  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  22  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  23  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  24  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  25  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  26  * SUCH DAMAGE.
  27  */
  28
  29 #ifndef _ARCH_MSR_H
  30 #define _ARCH_MSR_H
  31
  32 static inline unsigned long long _rdmsr(unsigned int msr)
  33 {
  34         unsigned long long val;
  35         asm volatile("rdmsr" : "=A" (val) : "c" (msr));
  36         return val;
  37 }
  38
  39 static inline void _wrmsr(unsigned int msr, unsigned long long val)
  40 {
  41         asm volatile("wrmsr" : : "c" (msr), "A"(val));
  42 }
  43
  44 #define rdmsr(_m, _l, _h) \
  45         do { \
  46                 unsigned long long _v = _rdmsr((_m)); \
  47                 (_l) = (unsigned int) _v; \
  48                 (_h) = (unsigned int) ((_v >> 32) & 0xFFFFFFFF); \
  49         } while(0)
  50
  51 static inline void wrmsr(unsigned int msr, unsigned int lo, unsigned int hi)
  52 {
  53         unsigned long long val = (((unsigned long long) hi) << 32) | lo;
  54         _wrmsr(msr, val);
  55 }
  56
  57 #endif