drivers/staging/unisys/visorutil/visorkmodutils.c

   1 /* timskmodutils.c
   2  *
   3  * Copyright (C) 2010 - 2013 UNISYS CORPORATION
   4  * All rights reserved.
   5  *
   6  * This program is free software; you can redistribute it and/or modify
   7  * it under the terms of the GNU General Public License as published by
   8  * the Free Software Foundation; either version 2 of the License, or (at
   9  * your option) any later version.
  10  *
  11  * This program is distributed in the hope that it will be useful, but
  12  * WITHOUT ANY WARRANTY; without even the implied warranty of
  13  * MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE, GOOD TITLE or
  14  * NON INFRINGEMENT.  See the GNU General Public License for more
  15  * details.
  16  */
  17
  18 #include "timskmod.h"
  19
  20 #define MYDRVNAME "timskmodutils"
  21
  22 /* s-Par uses the Intel processor's VT-X features to separate groups of
  23  * processors into partitions. The firmware sets the hypervisor bit and
  24  * reports an ID in the HV capabilities leaf so that the partition's OS
  25  * knows s-Par is present and managing the processors.
  26  */
  27
  28 #define UNISYS_SPAR_LEAF_ID 0x40000000
  29
  30 /* The s-Par leaf ID returns "UnisysSpar64" encoded across ebx, ecx, edx */
  31 #define UNISYS_SPAR_ID_EBX 0x73696e55
  32 #define UNISYS_SPAR_ID_ECX 0x70537379
  33 #define UNISYS_SPAR_ID_EDX 0x34367261
  34
  35 int unisys_spar_platform;
  36 EXPORT_SYMBOL_GPL(unisys_spar_platform);
  37
  38 static __init uint32_t visorutil_spar_detect(void)
  39 {
  40         unsigned int eax, ebx, ecx, edx;
  41
  42         if (cpu_has_hypervisor) {
  43                 /* check the ID */
  44                 cpuid(UNISYS_SPAR_LEAF_ID, &eax, &ebx, &ecx, &edx);
  45                 return  (ebx == UNISYS_SPAR_ID_EBX) &&
  46                         (ecx == UNISYS_SPAR_ID_ECX) &&
  47                         (edx == UNISYS_SPAR_ID_EDX);
  48         } else {
  49                 return 0;
  50         }
  51 }
  52
  53 static __init int visorutil_mod_init(void)
  54 {
  55         if (visorutil_spar_detect()) {
  56                 unisys_spar_platform = TRUE;
  57                 return 0;
  58         } else {
  59                 return -ENODEV;
  60         }
  61 }
  62
  63 static __exit void
  64 visorutil_mod_exit(void)
  65 {
  66 }
  67
  68 module_init(visorutil_mod_init);
  69 module_exit(visorutil_mod_exit);
  70
  71 MODULE_LICENSE("GPL");