projects / linux-block.git / blame
| Commit | Line | Data |
|---|---|---|
| 88b094fb AK |
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), \ | |
| 6bdbfe99 | 39 | "2"(VMWARE_HYPERVISOR_PORT), "3"(UINT_MAX) : \ |
| 88b094fb AK |
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 | ||
| 6bdbfe99 | 56 | if (ebx == UINT_MAX) |
| 88b094fb AK |
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 | } | |
| eca0cd02 AK |
89 | |
| 90 | /* | |
| 91 | * VMware hypervisor takes care of exporting a reliable TSC to the guest. | |
| 92 | * Still, due to timing difference when running on virtual cpus, the TSC can | |
| 93 | * be marked as unstable in some cases. For example, the TSC sync check at | |
| 94 | * bootup can fail due to a marginal offset between vcpus' TSCs (though the | |
| 95 | * TSCs do not drift from each other). Also, the ACPI PM timer clocksource | |
| 96 | * is not suitable as a watchdog when running on a hypervisor because the | |
| 97 | * kernel may miss a wrap of the counter if the vcpu is descheduled for a | |
| 98 | * long time. To skip these checks at runtime we set these capability bits, | |
| 99 | * so that the kernel could just trust the hypervisor with providing a | |
| 100 | * reliable virtual TSC that is suitable for timekeeping. | |
| 101 | */ | |
| 102 | void __cpuinit vmware_set_feature_bits(struct cpuinfo_x86 *c) | |
| 103 | { | |
| 104 | set_cpu_cap(c, X86_FEATURE_CONSTANT_TSC); | |
| 105 | set_cpu_cap(c, X86_FEATURE_TSC_RELIABLE); | |
| 106 | } |