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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 <linux/init.h>
26#include <linux/export.h>
27#include <linux/clocksource.h>
28#include <asm/div64.h>
29#include <asm/x86_init.h>
30#include <asm/hypervisor.h>
31#include <asm/timer.h>
32#include <asm/apic.h>
33#include <asm/vmware.h>
34
35#undef pr_fmt
36#define pr_fmt(fmt) "vmware: " fmt
37
38#define CPUID_VMWARE_INFO_LEAF 0x40000000
39#define CPUID_VMWARE_FEATURES_LEAF 0x40000010
40#define CPUID_VMWARE_FEATURES_ECX_VMMCALL BIT(0)
41#define CPUID_VMWARE_FEATURES_ECX_VMCALL BIT(1)
42
43#define VMWARE_HYPERVISOR_MAGIC 0x564D5868
44
45#define VMWARE_CMD_GETVERSION 10
46#define VMWARE_CMD_GETHZ 45
47#define VMWARE_CMD_GETVCPU_INFO 68
48#define VMWARE_CMD_LEGACY_X2APIC 3
49#define VMWARE_CMD_VCPU_RESERVED 31
50
51#define VMWARE_PORT(cmd, eax, ebx, ecx, edx) \
52 __asm__("inl (%%dx), %%eax" : \
53 "=a"(eax), "=c"(ecx), "=d"(edx), "=b"(ebx) : \
54 "a"(VMWARE_HYPERVISOR_MAGIC), \
55 "c"(VMWARE_CMD_##cmd), \
56 "d"(VMWARE_HYPERVISOR_PORT), "b"(UINT_MAX) : \
57 "memory")
58
59#define VMWARE_VMCALL(cmd, eax, ebx, ecx, edx) \
60 __asm__("vmcall" : \
61 "=a"(eax), "=c"(ecx), "=d"(edx), "=b"(ebx) : \
62 "a"(VMWARE_HYPERVISOR_MAGIC), \
63 "c"(VMWARE_CMD_##cmd), \
64 "d"(0), "b"(UINT_MAX) : \
65 "memory")
66
67#define VMWARE_VMMCALL(cmd, eax, ebx, ecx, edx) \
68 __asm__("vmmcall" : \
69 "=a"(eax), "=c"(ecx), "=d"(edx), "=b"(ebx) : \
70 "a"(VMWARE_HYPERVISOR_MAGIC), \
71 "c"(VMWARE_CMD_##cmd), \
72 "d"(0), "b"(UINT_MAX) : \
73 "memory")
74
75#define VMWARE_CMD(cmd, eax, ebx, ecx, edx) do { \
76 switch (vmware_hypercall_mode) { \
77 case CPUID_VMWARE_FEATURES_ECX_VMCALL: \
78 VMWARE_VMCALL(cmd, eax, ebx, ecx, edx); \
79 break; \
80 case CPUID_VMWARE_FEATURES_ECX_VMMCALL: \
81 VMWARE_VMMCALL(cmd, eax, ebx, ecx, edx); \
82 break; \
83 default: \
84 VMWARE_PORT(cmd, eax, ebx, ecx, edx); \
85 break; \
86 } \
87 } while (0)
88
89static unsigned long vmware_tsc_khz __ro_after_init;
90static u8 vmware_hypercall_mode __ro_after_init;
91
92static inline int __vmware_platform(void)
93{
94 uint32_t eax, ebx, ecx, edx;
95 VMWARE_CMD(GETVERSION, eax, ebx, ecx, edx);
96 return eax != (uint32_t)-1 && ebx == VMWARE_HYPERVISOR_MAGIC;
97}
98
99static unsigned long vmware_get_tsc_khz(void)
100{
101 return vmware_tsc_khz;
102}
103
104#ifdef CONFIG_PARAVIRT
105static struct cyc2ns_data vmware_cyc2ns __ro_after_init;
106static int vmw_sched_clock __initdata = 1;
107
108static __init int setup_vmw_sched_clock(char *s)
109{
110 vmw_sched_clock = 0;
111 return 0;
112}
113early_param("no-vmw-sched-clock", setup_vmw_sched_clock);
114
115static unsigned long long notrace vmware_sched_clock(void)
116{
117 unsigned long long ns;
118
119 ns = mul_u64_u32_shr(rdtsc(), vmware_cyc2ns.cyc2ns_mul,
120 vmware_cyc2ns.cyc2ns_shift);
121 ns -= vmware_cyc2ns.cyc2ns_offset;
122 return ns;
123}
124
125static void __init vmware_sched_clock_setup(void)
126{
127 struct cyc2ns_data *d = &vmware_cyc2ns;
128 unsigned long long tsc_now = rdtsc();
129
130 clocks_calc_mult_shift(&d->cyc2ns_mul, &d->cyc2ns_shift,
131 vmware_tsc_khz, NSEC_PER_MSEC, 0);
132 d->cyc2ns_offset = mul_u64_u32_shr(tsc_now, d->cyc2ns_mul,
133 d->cyc2ns_shift);
134
135 pv_ops.time.sched_clock = vmware_sched_clock;
136 pr_info("using sched offset of %llu ns\n", d->cyc2ns_offset);
137}
138
139static void __init vmware_paravirt_ops_setup(void)
140{
141 pv_info.name = "VMware hypervisor";
142 pv_ops.cpu.io_delay = paravirt_nop;
143
144 if (vmware_tsc_khz && vmw_sched_clock)
145 vmware_sched_clock_setup();
146}
147#else
148#define vmware_paravirt_ops_setup() do {} while (0)
149#endif
150
151/*
152 * VMware hypervisor takes care of exporting a reliable TSC to the guest.
153 * Still, due to timing difference when running on virtual cpus, the TSC can
154 * be marked as unstable in some cases. For example, the TSC sync check at
155 * bootup can fail due to a marginal offset between vcpus' TSCs (though the
156 * TSCs do not drift from each other). Also, the ACPI PM timer clocksource
157 * is not suitable as a watchdog when running on a hypervisor because the
158 * kernel may miss a wrap of the counter if the vcpu is descheduled for a
159 * long time. To skip these checks at runtime we set these capability bits,
160 * so that the kernel could just trust the hypervisor with providing a
161 * reliable virtual TSC that is suitable for timekeeping.
162 */
163static void __init vmware_set_capabilities(void)
164{
165 setup_force_cpu_cap(X86_FEATURE_CONSTANT_TSC);
166 setup_force_cpu_cap(X86_FEATURE_TSC_RELIABLE);
167 if (vmware_hypercall_mode == CPUID_VMWARE_FEATURES_ECX_VMCALL)
168 setup_force_cpu_cap(X86_FEATURE_VMCALL);
169 else if (vmware_hypercall_mode == CPUID_VMWARE_FEATURES_ECX_VMMCALL)
170 setup_force_cpu_cap(X86_FEATURE_VMW_VMMCALL);
171}
172
173static void __init vmware_platform_setup(void)
174{
175 uint32_t eax, ebx, ecx, edx;
176 uint64_t lpj, tsc_khz;
177
178 VMWARE_CMD(GETHZ, eax, ebx, ecx, edx);
179
180 if (ebx != UINT_MAX) {
181 lpj = tsc_khz = eax | (((uint64_t)ebx) << 32);
182 do_div(tsc_khz, 1000);
183 WARN_ON(tsc_khz >> 32);
184 pr_info("TSC freq read from hypervisor : %lu.%03lu MHz\n",
185 (unsigned long) tsc_khz / 1000,
186 (unsigned long) tsc_khz % 1000);
187
188 if (!preset_lpj) {
189 do_div(lpj, HZ);
190 preset_lpj = lpj;
191 }
192
193 vmware_tsc_khz = tsc_khz;
194 x86_platform.calibrate_tsc = vmware_get_tsc_khz;
195 x86_platform.calibrate_cpu = vmware_get_tsc_khz;
196
197#ifdef CONFIG_X86_LOCAL_APIC
198 /* Skip lapic calibration since we know the bus frequency. */
199 lapic_timer_period = ecx / HZ;
200 pr_info("Host bus clock speed read from hypervisor : %u Hz\n",
201 ecx);
202#endif
203 } else {
204 pr_warn("Failed to get TSC freq from the hypervisor\n");
205 }
206
207 vmware_paravirt_ops_setup();
208
209#ifdef CONFIG_X86_IO_APIC
210 no_timer_check = 1;
211#endif
212
213 vmware_set_capabilities();
214}
215
216static u8 vmware_select_hypercall(void)
217{
218 int eax, ebx, ecx, edx;
219
220 cpuid(CPUID_VMWARE_FEATURES_LEAF, &eax, &ebx, &ecx, &edx);
221 return (ecx & (CPUID_VMWARE_FEATURES_ECX_VMMCALL |
222 CPUID_VMWARE_FEATURES_ECX_VMCALL));
223}
224
225/*
226 * While checking the dmi string information, just checking the product
227 * serial key should be enough, as this will always have a VMware
228 * specific string when running under VMware hypervisor.
229 * If !boot_cpu_has(X86_FEATURE_HYPERVISOR), vmware_hypercall_mode
230 * intentionally defaults to 0.
231 */
232static uint32_t __init vmware_platform(void)
233{
234 if (boot_cpu_has(X86_FEATURE_HYPERVISOR)) {
235 unsigned int eax;
236 unsigned int hyper_vendor_id[3];
237
238 cpuid(CPUID_VMWARE_INFO_LEAF, &eax, &hyper_vendor_id[0],
239 &hyper_vendor_id[1], &hyper_vendor_id[2]);
240 if (!memcmp(hyper_vendor_id, "VMwareVMware", 12)) {
241 if (eax >= CPUID_VMWARE_FEATURES_LEAF)
242 vmware_hypercall_mode =
243 vmware_select_hypercall();
244
245 pr_info("hypercall mode: 0x%02x\n",
246 (unsigned int) vmware_hypercall_mode);
247
248 return CPUID_VMWARE_INFO_LEAF;
249 }
250 } else if (dmi_available && dmi_name_in_serial("VMware") &&
251 __vmware_platform())
252 return 1;
253
254 return 0;
255}
256
257/* Checks if hypervisor supports x2apic without VT-D interrupt remapping. */
258static bool __init vmware_legacy_x2apic_available(void)
259{
260 uint32_t eax, ebx, ecx, edx;
261 VMWARE_CMD(GETVCPU_INFO, eax, ebx, ecx, edx);
262 return (eax & (1 << VMWARE_CMD_VCPU_RESERVED)) == 0 &&
263 (eax & (1 << VMWARE_CMD_LEGACY_X2APIC)) != 0;
264}
265
266const __initconst struct hypervisor_x86 x86_hyper_vmware = {
267 .name = "VMware",
268 .detect = vmware_platform,
269 .type = X86_HYPER_VMWARE,
270 .init.init_platform = vmware_platform_setup,
271 .init.x2apic_available = vmware_legacy_x2apic_available,
272};
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 <linux/module.h>
26#include <asm/div64.h>
27#include <asm/x86_init.h>
28#include <asm/hypervisor.h>
29
30#define CPUID_VMWARE_INFO_LEAF 0x40000000
31#define VMWARE_HYPERVISOR_MAGIC 0x564D5868
32#define VMWARE_HYPERVISOR_PORT 0x5658
33
34#define VMWARE_PORT_CMD_GETVERSION 10
35#define VMWARE_PORT_CMD_GETHZ 45
36
37#define VMWARE_PORT(cmd, eax, ebx, ecx, edx) \
38 __asm__("inl (%%dx)" : \
39 "=a"(eax), "=c"(ecx), "=d"(edx), "=b"(ebx) : \
40 "0"(VMWARE_HYPERVISOR_MAGIC), \
41 "1"(VMWARE_PORT_CMD_##cmd), \
42 "2"(VMWARE_HYPERVISOR_PORT), "3"(UINT_MAX) : \
43 "memory");
44
45static inline int __vmware_platform(void)
46{
47 uint32_t eax, ebx, ecx, edx;
48 VMWARE_PORT(GETVERSION, eax, ebx, ecx, edx);
49 return eax != (uint32_t)-1 && ebx == VMWARE_HYPERVISOR_MAGIC;
50}
51
52static unsigned long vmware_get_tsc_khz(void)
53{
54 uint64_t tsc_hz, lpj;
55 uint32_t eax, ebx, ecx, edx;
56
57 VMWARE_PORT(GETHZ, eax, ebx, ecx, edx);
58
59 tsc_hz = eax | (((uint64_t)ebx) << 32);
60 do_div(tsc_hz, 1000);
61 BUG_ON(tsc_hz >> 32);
62 printk(KERN_INFO "TSC freq read from hypervisor : %lu.%03lu MHz\n",
63 (unsigned long) tsc_hz / 1000,
64 (unsigned long) tsc_hz % 1000);
65
66 if (!preset_lpj) {
67 lpj = ((u64)tsc_hz * 1000);
68 do_div(lpj, HZ);
69 preset_lpj = lpj;
70 }
71
72 return tsc_hz;
73}
74
75static void __init vmware_platform_setup(void)
76{
77 uint32_t eax, ebx, ecx, edx;
78
79 VMWARE_PORT(GETHZ, eax, ebx, ecx, edx);
80
81 if (ebx != UINT_MAX)
82 x86_platform.calibrate_tsc = vmware_get_tsc_khz;
83 else
84 printk(KERN_WARNING
85 "Failed to get TSC freq from the hypervisor\n");
86}
87
88/*
89 * While checking the dmi string information, just checking the product
90 * serial key should be enough, as this will always have a VMware
91 * specific string when running under VMware hypervisor.
92 */
93static bool __init vmware_platform(void)
94{
95 if (cpu_has_hypervisor) {
96 unsigned int eax;
97 unsigned int hyper_vendor_id[3];
98
99 cpuid(CPUID_VMWARE_INFO_LEAF, &eax, &hyper_vendor_id[0],
100 &hyper_vendor_id[1], &hyper_vendor_id[2]);
101 if (!memcmp(hyper_vendor_id, "VMwareVMware", 12))
102 return true;
103 } else if (dmi_available && dmi_name_in_serial("VMware") &&
104 __vmware_platform())
105 return true;
106
107 return false;
108}
109
110/*
111 * VMware hypervisor takes care of exporting a reliable TSC to the guest.
112 * Still, due to timing difference when running on virtual cpus, the TSC can
113 * be marked as unstable in some cases. For example, the TSC sync check at
114 * bootup can fail due to a marginal offset between vcpus' TSCs (though the
115 * TSCs do not drift from each other). Also, the ACPI PM timer clocksource
116 * is not suitable as a watchdog when running on a hypervisor because the
117 * kernel may miss a wrap of the counter if the vcpu is descheduled for a
118 * long time. To skip these checks at runtime we set these capability bits,
119 * so that the kernel could just trust the hypervisor with providing a
120 * reliable virtual TSC that is suitable for timekeeping.
121 */
122static void __cpuinit vmware_set_cpu_features(struct cpuinfo_x86 *c)
123{
124 set_cpu_cap(c, X86_FEATURE_CONSTANT_TSC);
125 set_cpu_cap(c, X86_FEATURE_TSC_RELIABLE);
126}
127
128const __refconst struct hypervisor_x86 x86_hyper_vmware = {
129 .name = "VMware",
130 .detect = vmware_platform,
131 .set_cpu_features = vmware_set_cpu_features,
132 .init_platform = vmware_platform_setup,
133};
134EXPORT_SYMBOL(x86_hyper_vmware);