arch/x86/kernel/cpu/vmware.c

   1 /*
   2  * VMware Detection code.
   3  *
   4  * Copyright (C) 2008, VMware, Inc.
   5  * Author : Alok N Kataria <akataria@vmware.com>
   6  *
   7  * This program is free software; you can redistribute it and/or modify
   8  * it under the terms of the GNU General Public License as published by
   9  * the Free Software Foundation; either version 2 of the License, or
  10  * (at your option) any later version.
  11  *
  12  * This program is distributed in the hope that it will be useful, but
  13  * WITHOUT ANY WARRANTY; without even the implied warranty of
  14  * MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE, GOOD TITLE or
  15  * NON INFRINGEMENT.  See the GNU General Public License for more
  16  * details.
  17  *
  18  * You should have received a copy of the GNU General Public License
  19  * along with this program; if not, write to the Free Software
  20  * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
  21  *
  22  */
  23
  24 #include <linux/dmi.h>
  25 #include <asm/div64.h>
  26
  27 #define CPUID_VMWARE_INFO_LEAF  0x40000000
  28 #define VMWARE_HYPERVISOR_MAGIC 0x564D5868
  29 #define VMWARE_HYPERVISOR_PORT  0x5658
  30
  31 #define VMWARE_PORT_CMD_GETVERSION      10
  32 #define VMWARE_PORT_CMD_GETHZ           45
  33
  34 #define VMWARE_PORT(cmd, eax, ebx, ecx, edx)                            \
  35         __asm__("inl (%%dx)" :                                          \
  36                         "=a"(eax), "=c"(ecx), "=d"(edx), "=b"(ebx) :    \
  37                         "0"(VMWARE_HYPERVISOR_MAGIC),                   \
  38                         "1"(VMWARE_PORT_CMD_##cmd),                     \
  39                         "2"(VMWARE_HYPERVISOR_PORT), "3"(0) :           \
  40                         "memory");
  41
  42 static inline int __vmware_platform(void)
  43 {
  44         uint32_t eax, ebx, ecx, edx;
  45         VMWARE_PORT(GETVERSION, eax, ebx, ecx, edx);
  46         return eax != (uint32_t)-1 && ebx == VMWARE_HYPERVISOR_MAGIC;
  47 }
  48
  49 static unsigned long __vmware_get_tsc_khz(void)
  50 {
  51         uint64_t tsc_hz;
  52         uint32_t eax, ebx, ecx, edx;
  53
  54         VMWARE_PORT(GETHZ, eax, ebx, ecx, edx);
  55
  56         if (eax == (uint32_t)-1)
  57                 return 0;
  58         tsc_hz = eax | (((uint64_t)ebx) << 32);
  59         do_div(tsc_hz, 1000);
  60         BUG_ON(tsc_hz >> 32);
  61         return tsc_hz;
  62 }
  63
  64 int vmware_platform(void)
  65 {
  66         if (cpu_has_hypervisor) {
  67                 unsigned int eax, ebx, ecx, edx;
  68                 char hyper_vendor_id[13];
  69
  70                 cpuid(CPUID_VMWARE_INFO_LEAF, &eax, &ebx, &ecx, &edx);
  71                 memcpy(hyper_vendor_id + 0, &ebx, 4);
  72                 memcpy(hyper_vendor_id + 4, &ecx, 4);
  73                 memcpy(hyper_vendor_id + 8, &edx, 4);
  74                 hyper_vendor_id[12] = '\0';
  75                 if (!strcmp(hyper_vendor_id, "VMwareVMware"))
  76                         return 1;
  77         } else if (dmi_available && dmi_name_in_vendors("VMware") &&
  78                    __vmware_platform())
  79                 return 1;
  80
  81         return 0;
  82 }
  83
  84 unsigned long vmware_get_tsc_khz(void)
  85 {
  86         BUG_ON(!vmware_platform());
  87         return __vmware_get_tsc_khz();
  88 }