i386: split cpu accelerators from cpu.c, using AccelCPUClass

i386 is the first user of AccelCPUClass, allowing to split
cpu.c into:

cpu.c            cpuid and common x86 cpu functionality
host-cpu.c       host x86 cpu functions and "host" cpu type
kvm/kvm-cpu.c    KVM x86 AccelCPUClass
hvf/hvf-cpu.c    HVF x86 AccelCPUClass
tcg/tcg-cpu.c    TCG x86 AccelCPUClass

Signed-off-by: Claudio Fontana <cfontana@suse.de>
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>

[claudio]:
Rebased on commit b8184135 ("target/i386: allow modifying TCG phys-addr-bits")

Signed-off-by: Claudio Fontana <cfontana@suse.de>
Message-Id: <20210322132800.7470-5-cfontana@suse.de>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

1 files changed, 201 insertions, 0 deletions

diff --git a/target/i386/host-cpu.c b/target/i386/host-cpu.c
new file mode 100644
index 0000000..9cfe56c
--- /dev/null
+++ b/target/i386/host-cpu.c
@@ -0,0 +1,201 @@
+/*
+ * 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, Error **errp)
+{
+    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;
+        }
+    }
+
+    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 phys_bits;
+}
+
+void 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) {
+        cpu->phys_bits = host_cpu_adjust_phys_bits(cpu, errp);
+    }
+}
+
+#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);