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authorDaniel Baumann <daniel.baumann@progress-linux.org>2024-05-06 01:02:30 +0000
committerDaniel Baumann <daniel.baumann@progress-linux.org>2024-05-06 01:02:30 +0000
commit76cb841cb886eef6b3bee341a2266c76578724ad (patch)
treef5892e5ba6cc11949952a6ce4ecbe6d516d6ce58 /arch/x86/kernel/cpu/vmware.c
parentInitial commit. (diff)
downloadlinux-76cb841cb886eef6b3bee341a2266c76578724ad.tar.xz
linux-76cb841cb886eef6b3bee341a2266c76578724ad.zip
Adding upstream version 4.19.249.upstream/4.19.249
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'arch/x86/kernel/cpu/vmware.c')
-rw-r--r--arch/x86/kernel/cpu/vmware.c214
1 files changed, 214 insertions, 0 deletions
diff --git a/arch/x86/kernel/cpu/vmware.c b/arch/x86/kernel/cpu/vmware.c
new file mode 100644
index 000000000..d805202c6
--- /dev/null
+++ b/arch/x86/kernel/cpu/vmware.c
@@ -0,0 +1,214 @@
+/*
+ * 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)" : \
+ "=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,
+};