arch/x86/kernel/cpu/vmware.c - kernel/common.git - Git at Google

 /*
  * 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/init.h>
 #include <linux/export.h>
 #include <linux/clocksource.h>
 #include <asm/div64.h>
 #include <asm/x86_init.h>
 #include <asm/hypervisor.h>
 #include <asm/timer.h>
 #include <asm/apic.h>

 #undef pr_fmt
 #define pr_fmt(fmt)	"vmware: " fmt

 #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), %%eax" :					\
 			"=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 unsigned long vmware_tsc_khz __ro_after_init;

 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)
 {
 	return vmware_tsc_khz;
 }

 #ifdef CONFIG_PARAVIRT
 static struct cyc2ns_data vmware_cyc2ns __ro_after_init;
 static int vmw_sched_clock __initdata = 1;

 static __init int setup_vmw_sched_clock(char *s)
 {
 	vmw_sched_clock = 0;
 	return 0;
 }
 early_param("no-vmw-sched-clock", setup_vmw_sched_clock);

 static unsigned long long notrace vmware_sched_clock(void)
 {
 	unsigned long long ns;

 	ns = mul_u64_u32_shr(rdtsc(), vmware_cyc2ns.cyc2ns_mul,
 			     vmware_cyc2ns.cyc2ns_shift);
 	ns -= vmware_cyc2ns.cyc2ns_offset;
 	return ns;
 }

 static void __init vmware_sched_clock_setup(void)
 {
 	struct cyc2ns_data *d = &vmware_cyc2ns;
 	unsigned long long tsc_now = rdtsc();

 	clocks_calc_mult_shift(&d->cyc2ns_mul, &d->cyc2ns_shift,
 			       vmware_tsc_khz, NSEC_PER_MSEC, 0);
 	d->cyc2ns_offset = mul_u64_u32_shr(tsc_now, d->cyc2ns_mul,
 					   d->cyc2ns_shift);

 	pv_time_ops.sched_clock = vmware_sched_clock;
 	pr_info("using sched offset of %llu ns\n", d->cyc2ns_offset);
 }

 static void __init vmware_paravirt_ops_setup(void)
 {
 	pv_info.name = "VMware hypervisor";
 	pv_cpu_ops.io_delay = paravirt_nop;

 	if (vmware_tsc_khz && vmw_sched_clock)
 		vmware_sched_clock_setup();
 }
 #else
 #define vmware_paravirt_ops_setup() do {} while (0)
 #endif

 /*
  * 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 __init vmware_set_capabilities(void)
 {
 	setup_force_cpu_cap(X86_FEATURE_CONSTANT_TSC);
 	setup_force_cpu_cap(X86_FEATURE_TSC_RELIABLE);
 }

 static void __init vmware_platform_setup(void)
 {
 	uint32_t eax, ebx, ecx, edx;
 	uint64_t lpj, tsc_khz;

 	VMWARE_PORT(GETHZ, eax, ebx, ecx, edx);

 	if (ebx != UINT_MAX) {
 		lpj = tsc_khz = eax | (((uint64_t)ebx) << 32);
 		do_div(tsc_khz, 1000);
 		WARN_ON(tsc_khz >> 32);
 		pr_info("TSC freq read from hypervisor : %lu.%03lu MHz\n",
 			(unsigned long) tsc_khz / 1000,
 			(unsigned long) tsc_khz % 1000);

 		if (!preset_lpj) {
 			do_div(lpj, HZ);
 			preset_lpj = lpj;
 		}

 		vmware_tsc_khz = tsc_khz;
 		x86_platform.calibrate_tsc = vmware_get_tsc_khz;
 		x86_platform.calibrate_cpu = vmware_get_tsc_khz;

 #ifdef CONFIG_X86_LOCAL_APIC
 		/* Skip lapic calibration since we know the bus frequency. */
 		lapic_timer_frequency = ecx / HZ;
 		pr_info("Host bus clock speed read from hypervisor : %u Hz\n",
 			ecx);
 #endif
 	} else {
 		pr_warn("Failed to get TSC freq from the hypervisor\n");
 	}

 	vmware_paravirt_ops_setup();

 #ifdef CONFIG_X86_IO_APIC
 	no_timer_check = 1;
 #endif

 	vmware_set_capabilities();
 }

 /*
  * 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 (boot_cpu_has(X86_FEATURE_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;
 }

 /* 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 __initconst struct hypervisor_x86 x86_hyper_vmware = {
 	.name			= "VMware",
 	.detect			= vmware_platform,
 	.type			= X86_HYPER_VMWARE,
 	.init.init_platform	= vmware_platform_setup,
 	.init.x2apic_available	= vmware_legacy_x2apic_available,
 };
	/*
	* 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/init.h>
	#include <linux/export.h>
	#include <linux/clocksource.h>
	#include <asm/div64.h>
	#include <asm/x86_init.h>
	#include <asm/hypervisor.h>
	#include <asm/timer.h>
	#include <asm/apic.h>

	#undef pr_fmt
	#define pr_fmt(fmt) "vmware: " fmt

	#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), %%eax" : \
	"=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 unsigned long vmware_tsc_khz __ro_after_init;

	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)
	{
	return vmware_tsc_khz;
	}

	#ifdef CONFIG_PARAVIRT
	static struct cyc2ns_data vmware_cyc2ns __ro_after_init;
	static int vmw_sched_clock __initdata = 1;

	static __init int setup_vmw_sched_clock(char *s)
	{
	vmw_sched_clock = 0;
	return 0;
	}
	early_param("no-vmw-sched-clock", setup_vmw_sched_clock);

	static unsigned long long notrace vmware_sched_clock(void)
	{
	unsigned long long ns;

	ns = mul_u64_u32_shr(rdtsc(), vmware_cyc2ns.cyc2ns_mul,
	vmware_cyc2ns.cyc2ns_shift);
	ns -= vmware_cyc2ns.cyc2ns_offset;
	return ns;
	}

	static void __init vmware_sched_clock_setup(void)
	{
	struct cyc2ns_data *d = &vmware_cyc2ns;
	unsigned long long tsc_now = rdtsc();

	clocks_calc_mult_shift(&d->cyc2ns_mul, &d->cyc2ns_shift,
	vmware_tsc_khz, NSEC_PER_MSEC, 0);
	d->cyc2ns_offset = mul_u64_u32_shr(tsc_now, d->cyc2ns_mul,
	d->cyc2ns_shift);

	pv_time_ops.sched_clock = vmware_sched_clock;
	pr_info("using sched offset of %llu ns\n", d->cyc2ns_offset);
	}

	static void __init vmware_paravirt_ops_setup(void)
	{
	pv_info.name = "VMware hypervisor";
	pv_cpu_ops.io_delay = paravirt_nop;

	if (vmware_tsc_khz && vmw_sched_clock)
	vmware_sched_clock_setup();
	}
	#else
	#define vmware_paravirt_ops_setup() do {} while (0)
	#endif

	/*
	* 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 __init vmware_set_capabilities(void)
	{
	setup_force_cpu_cap(X86_FEATURE_CONSTANT_TSC);
	setup_force_cpu_cap(X86_FEATURE_TSC_RELIABLE);
	}

	static void __init vmware_platform_setup(void)
	{
	uint32_t eax, ebx, ecx, edx;
	uint64_t lpj, tsc_khz;

	VMWARE_PORT(GETHZ, eax, ebx, ecx, edx);

	if (ebx != UINT_MAX) {
	lpj = tsc_khz = eax \| (((uint64_t)ebx) << 32);
	do_div(tsc_khz, 1000);
	WARN_ON(tsc_khz >> 32);
	pr_info("TSC freq read from hypervisor : %lu.%03lu MHz\n",
	(unsigned long) tsc_khz / 1000,
	(unsigned long) tsc_khz % 1000);

	if (!preset_lpj) {
	do_div(lpj, HZ);
	preset_lpj = lpj;
	}

	vmware_tsc_khz = tsc_khz;
	x86_platform.calibrate_tsc = vmware_get_tsc_khz;
	x86_platform.calibrate_cpu = vmware_get_tsc_khz;

	#ifdef CONFIG_X86_LOCAL_APIC
	/* Skip lapic calibration since we know the bus frequency. */
	lapic_timer_frequency = ecx / HZ;
	pr_info("Host bus clock speed read from hypervisor : %u Hz\n",
	ecx);
	#endif
	} else {
	pr_warn("Failed to get TSC freq from the hypervisor\n");
	}

	vmware_paravirt_ops_setup();

	#ifdef CONFIG_X86_IO_APIC
	no_timer_check = 1;
	#endif

	vmware_set_capabilities();
	}

	/*
	* 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 (boot_cpu_has(X86_FEATURE_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;
	}

	/* 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 __initconst struct hypervisor_x86 x86_hyper_vmware = {
	.name = "VMware",
	.detect = vmware_platform,
	.type = X86_HYPER_VMWARE,
	.init.init_platform = vmware_platform_setup,
	.init.x2apic_available = vmware_legacy_x2apic_available,
	};