blob: 8b8bf5afeccfcb4cfd08bbd37d675ed644b969c3 [file] [log] [blame]
/*
* 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 "qemu/error-report.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 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;
/*
* 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) {
warn_report_once("Host physical bits (%u)"
" does not match phys-bits property (%u)",
host_phys_bits, phys_bits);
}
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 (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)
{
X86CPUClass *xcc = X86_CPU_GET_CLASS(cpu);
if (xcc->model) {
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);