/* * VMware Detection code. * * Copyright (C) 2008, VMware, Inc. * Author : Alok N Kataria <akataria@vmware.com> * * This program is free software; you can redistribute it and/or modify * it under the terms of the GNU General Public License as published by * the Free Software Foundation; either version 2 of the License, or * (at your option) any later version. * * This program is distributed in the hope that it will be useful, but * WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE, GOOD TITLE or * NON INFRINGEMENT. See the GNU General Public License for more * details. * * You should have received a copy of the GNU General Public License * along with this program; if not, write to the Free Software * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. * */ #include <linux/dmi.h> #include <linux/module.h> #include <asm/div64.h> #include <asm/x86_init.h> #include <asm/hypervisor.h> #define CPUID_VMWARE_INFO_LEAF 0x40000000 #define VMWARE_HYPERVISOR_MAGIC 0x564D5868 #define VMWARE_HYPERVISOR_PORT 0x5658 #define VMWARE_PORT_CMD_GETVERSION 10 #define VMWARE_PORT_CMD_GETHZ 45 #define VMWARE_PORT_CMD_GETVCPU_INFO 68 #define VMWARE_PORT_CMD_LEGACY_X2APIC 3 #define VMWARE_PORT_CMD_VCPU_RESERVED 31 #define VMWARE_PORT(cmd, eax, ebx, ecx, edx) \ __asm__("inl (%%dx)" : \ "=a"(eax), "=c"(ecx), "=d"(edx), "=b"(ebx) : \ "0"(VMWARE_HYPERVISOR_MAGIC), \ "1"(VMWARE_PORT_CMD_##cmd), \ "2"(VMWARE_HYPERVISOR_PORT), "3"(UINT_MAX) : \ "memory"); static inline int __vmware_platform(void) { uint32_t eax, ebx, ecx, edx; VMWARE_PORT(GETVERSION, eax, ebx, ecx, edx); return eax != (uint32_t)-1 && ebx == VMWARE_HYPERVISOR_MAGIC; } static unsigned long vmware_get_tsc_khz(void) { uint64_t tsc_hz, lpj; uint32_t eax, ebx, ecx, edx; VMWARE_PORT(GETHZ, eax, ebx, ecx, edx); tsc_hz = eax | (((uint64_t)ebx) << 32); do_div(tsc_hz, 1000); BUG_ON(tsc_hz >> 32); printk(KERN_INFO "TSC freq read from hypervisor : %lu.%03lu MHz\n", (unsigned long) tsc_hz / 1000, (unsigned long) tsc_hz % 1000); if (!preset_lpj) { lpj = ((u64)tsc_hz * 1000); do_div(lpj, HZ); preset_lpj = lpj; } return tsc_hz; } static void __init vmware_platform_setup(void) { uint32_t eax, ebx, ecx, edx; VMWARE_PORT(GETHZ, eax, ebx, ecx, edx); if (ebx != UINT_MAX) x86_platform.calibrate_tsc = vmware_get_tsc_khz; else printk(KERN_WARNING "Failed to get TSC freq from the hypervisor\n"); } /* * While checking the dmi string information, just checking the product * serial key should be enough, as this will always have a VMware * specific string when running under VMware hypervisor. */ static uint32_t __init vmware_platform(void) { if (cpu_has_hypervisor) { unsigned int eax; unsigned int hyper_vendor_id[3]; cpuid(CPUID_VMWARE_INFO_LEAF, &eax, &hyper_vendor_id[0], &hyper_vendor_id[1], &hyper_vendor_id[2]); if (!memcmp(hyper_vendor_id, "VMwareVMware", 12)) return CPUID_VMWARE_INFO_LEAF; } else if (dmi_available && dmi_name_in_serial("VMware") && __vmware_platform()) return 1; return 0; } /* * VMware hypervisor takes care of exporting a reliable TSC to the guest. * Still, due to timing difference when running on virtual cpus, the TSC can * be marked as unstable in some cases. For example, the TSC sync check at * bootup can fail due to a marginal offset between vcpus' TSCs (though the * TSCs do not drift from each other). Also, the ACPI PM timer clocksource * is not suitable as a watchdog when running on a hypervisor because the * kernel may miss a wrap of the counter if the vcpu is descheduled for a * long time. To skip these checks at runtime we set these capability bits, * so that the kernel could just trust the hypervisor with providing a * reliable virtual TSC that is suitable for timekeeping. */ static void vmware_set_cpu_features(struct cpuinfo_x86 *c) { set_cpu_cap(c, X86_FEATURE_CONSTANT_TSC); set_cpu_cap(c, X86_FEATURE_TSC_RELIABLE); } /* Checks if hypervisor supports x2apic without VT-D interrupt remapping. */ static bool __init vmware_legacy_x2apic_available(void) { uint32_t eax, ebx, ecx, edx; VMWARE_PORT(GETVCPU_INFO, eax, ebx, ecx, edx); return (eax & (1 << VMWARE_PORT_CMD_VCPU_RESERVED)) == 0 && (eax & (1 << VMWARE_PORT_CMD_LEGACY_X2APIC)) != 0; } const __refconst struct hypervisor_x86 x86_hyper_vmware = { .name = "VMware", .detect = vmware_platform, .set_cpu_features = vmware_set_cpu_features, .init_platform = vmware_platform_setup, .x2apic_available = vmware_legacy_x2apic_available, }; EXPORT_SYMBOL(x86_hyper_vmware);