aboutsummaryrefslogtreecommitdiff
path: root/target/i386/host-cpu.c
diff options
context:
space:
mode:
Diffstat (limited to 'target/i386/host-cpu.c')
-rw-r--r--target/i386/host-cpu.c204
1 files changed, 204 insertions, 0 deletions
diff --git a/target/i386/host-cpu.c b/target/i386/host-cpu.c
new file mode 100644
index 0000000000..4ea9e354ea
--- /dev/null
+++ b/target/i386/host-cpu.c
@@ -0,0 +1,204 @@
+/*
+ * x86 host CPU functions, and "host" cpu type initialization
+ *
+ * Copyright 2021 SUSE LLC
+ *
+ * This work is licensed under the terms of the GNU GPL, version 2 or later.
+ * See the COPYING file in the top-level directory.
+ */
+
+#include "qemu/osdep.h"
+#include "cpu.h"
+#include "host-cpu.h"
+#include "qapi/error.h"
+#include "sysemu/sysemu.h"
+
+/* Note: Only safe for use on x86(-64) hosts */
+static uint32_t host_cpu_phys_bits(void)
+{
+ uint32_t eax;
+ uint32_t host_phys_bits;
+
+ host_cpuid(0x80000000, 0, &eax, NULL, NULL, NULL);
+ if (eax >= 0x80000008) {
+ host_cpuid(0x80000008, 0, &eax, NULL, NULL, NULL);
+ /*
+ * Note: According to AMD doc 25481 rev 2.34 they have a field
+ * at 23:16 that can specify a maximum physical address bits for
+ * the guest that can override this value; but I've not seen
+ * anything with that set.
+ */
+ host_phys_bits = eax & 0xff;
+ } else {
+ /*
+ * It's an odd 64 bit machine that doesn't have the leaf for
+ * physical address bits; fall back to 36 that's most older
+ * Intel.
+ */
+ host_phys_bits = 36;
+ }
+
+ return host_phys_bits;
+}
+
+static void host_cpu_enable_cpu_pm(X86CPU *cpu)
+{
+ CPUX86State *env = &cpu->env;
+
+ host_cpuid(5, 0, &cpu->mwait.eax, &cpu->mwait.ebx,
+ &cpu->mwait.ecx, &cpu->mwait.edx);
+ env->features[FEAT_1_ECX] |= CPUID_EXT_MONITOR;
+}
+
+static uint32_t host_cpu_adjust_phys_bits(X86CPU *cpu)
+{
+ uint32_t host_phys_bits = host_cpu_phys_bits();
+ uint32_t phys_bits = cpu->phys_bits;
+ static bool warned;
+
+ /*
+ * Print a warning if the user set it to a value that's not the
+ * host value.
+ */
+ if (phys_bits != host_phys_bits && phys_bits != 0 &&
+ !warned) {
+ warn_report("Host physical bits (%u)"
+ " does not match phys-bits property (%u)",
+ host_phys_bits, phys_bits);
+ warned = true;
+ }
+
+ if (cpu->host_phys_bits) {
+ /* The user asked for us to use the host physical bits */
+ phys_bits = host_phys_bits;
+ if (cpu->host_phys_bits_limit &&
+ phys_bits > cpu->host_phys_bits_limit) {
+ phys_bits = cpu->host_phys_bits_limit;
+ }
+ }
+
+ return phys_bits;
+}
+
+bool host_cpu_realizefn(CPUState *cs, Error **errp)
+{
+ X86CPU *cpu = X86_CPU(cs);
+ CPUX86State *env = &cpu->env;
+
+ if (cpu->max_features && enable_cpu_pm) {
+ host_cpu_enable_cpu_pm(cpu);
+ }
+ if (env->features[FEAT_8000_0001_EDX] & CPUID_EXT2_LM) {
+ uint32_t phys_bits = host_cpu_adjust_phys_bits(cpu);
+
+ if (phys_bits &&
+ (phys_bits > TARGET_PHYS_ADDR_SPACE_BITS ||
+ phys_bits < 32)) {
+ error_setg(errp, "phys-bits should be between 32 and %u "
+ " (but is %u)",
+ TARGET_PHYS_ADDR_SPACE_BITS, phys_bits);
+ return false;
+ }
+ cpu->phys_bits = phys_bits;
+ }
+ return true;
+}
+
+#define CPUID_MODEL_ID_SZ 48
+/**
+ * cpu_x86_fill_model_id:
+ * Get CPUID model ID string from host CPU.
+ *
+ * @str should have at least CPUID_MODEL_ID_SZ bytes
+ *
+ * The function does NOT add a null terminator to the string
+ * automatically.
+ */
+static int host_cpu_fill_model_id(char *str)
+{
+ uint32_t eax = 0, ebx = 0, ecx = 0, edx = 0;
+ int i;
+
+ for (i = 0; i < 3; i++) {
+ host_cpuid(0x80000002 + i, 0, &eax, &ebx, &ecx, &edx);
+ memcpy(str + i * 16 + 0, &eax, 4);
+ memcpy(str + i * 16 + 4, &ebx, 4);
+ memcpy(str + i * 16 + 8, &ecx, 4);
+ memcpy(str + i * 16 + 12, &edx, 4);
+ }
+ return 0;
+}
+
+void host_cpu_vendor_fms(char *vendor, int *family, int *model, int *stepping)
+{
+ uint32_t eax, ebx, ecx, edx;
+
+ host_cpuid(0x0, 0, &eax, &ebx, &ecx, &edx);
+ x86_cpu_vendor_words2str(vendor, ebx, edx, ecx);
+
+ host_cpuid(0x1, 0, &eax, &ebx, &ecx, &edx);
+ if (family) {
+ *family = ((eax >> 8) & 0x0F) + ((eax >> 20) & 0xFF);
+ }
+ if (model) {
+ *model = ((eax >> 4) & 0x0F) | ((eax & 0xF0000) >> 12);
+ }
+ if (stepping) {
+ *stepping = eax & 0x0F;
+ }
+}
+
+void host_cpu_instance_init(X86CPU *cpu)
+{
+ uint32_t ebx = 0, ecx = 0, edx = 0;
+ char vendor[CPUID_VENDOR_SZ + 1];
+
+ host_cpuid(0, 0, NULL, &ebx, &ecx, &edx);
+ x86_cpu_vendor_words2str(vendor, ebx, edx, ecx);
+
+ object_property_set_str(OBJECT(cpu), "vendor", vendor, &error_abort);
+}
+
+void host_cpu_max_instance_init(X86CPU *cpu)
+{
+ char vendor[CPUID_VENDOR_SZ + 1] = { 0 };
+ char model_id[CPUID_MODEL_ID_SZ + 1] = { 0 };
+ int family, model, stepping;
+
+ /* Use max host physical address bits if -cpu max option is applied */
+ object_property_set_bool(OBJECT(cpu), "host-phys-bits", true, &error_abort);
+
+ host_cpu_vendor_fms(vendor, &family, &model, &stepping);
+ host_cpu_fill_model_id(model_id);
+
+ object_property_set_str(OBJECT(cpu), "vendor", vendor, &error_abort);
+ object_property_set_int(OBJECT(cpu), "family", family, &error_abort);
+ object_property_set_int(OBJECT(cpu), "model", model, &error_abort);
+ object_property_set_int(OBJECT(cpu), "stepping", stepping,
+ &error_abort);
+ object_property_set_str(OBJECT(cpu), "model-id", model_id,
+ &error_abort);
+}
+
+static void host_cpu_class_init(ObjectClass *oc, void *data)
+{
+ X86CPUClass *xcc = X86_CPU_CLASS(oc);
+
+ xcc->host_cpuid_required = true;
+ xcc->ordering = 8;
+ xcc->model_description =
+ g_strdup_printf("processor with all supported host features ");
+}
+
+static const TypeInfo host_cpu_type_info = {
+ .name = X86_CPU_TYPE_NAME("host"),
+ .parent = X86_CPU_TYPE_NAME("max"),
+ .class_init = host_cpu_class_init,
+};
+
+static void host_cpu_type_init(void)
+{
+ type_register_static(&host_cpu_type_info);
+}
+
+type_init(host_cpu_type_init);