arch/x86: Populate more fields in SMBIOS type 4

If CPUID leaf 0x16 is available (Skylake and later) use it to obtain
current and maximum speed. Otherwise call weak function that can be
provided elsewhere (cpu/soc/mainboard). Also, populate "core enabled"
with the same value as "core count".

TEST=tested on OCP Monolake with dmidecode -t processor

Change-Id: Ie5d88dacae6623dfa0ceb3ca1bb5eeff2adda103
Signed-off-by: Andrey Petrov <anpetrov@fb.com>
Reviewed-on: https://review.coreboot.org/c/coreboot/+/36283
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
Reviewed-by: David Hendricks <david.hendricks@gmail.com>

src/arch/x86/smbios.c

@@ -522,6 +522,16 @@ void __weak smbios_system_set_uuid(u8 *uuid)
 	/* leave all zero */
 }
 
+unsigned int __weak smbios_cpu_get_max_speed_mhz(void)
+{
+	return 0; /* Unknown */
+}
+
+unsigned int __weak smbios_cpu_get_current_speed_mhz(void)
+{
+	return 0; /* Unknown */
+}
+
 const char *__weak smbios_system_sku(void)
 {
 	return "";
@@ -648,11 +658,20 @@ static int smbios_write_type4(unsigned long *current, int handle)
 	t->processor_family = (res.eax > 0) ? 0x0c : 0x6;
 	t->processor_type = 3; /* System Processor */
 	t->core_count = (res.ebx >> 16) & 0xff;
+	/* Assume we enable all the cores always, capped only by MAX_CPUS */
+	t->core_enabled = MAX(t->core_count, CONFIG_MAX_CPUS);
 	t->l1_cache_handle = 0xffff;
 	t->l2_cache_handle = 0xffff;
 	t->l3_cache_handle = 0xffff;
 	t->processor_upgrade = get_socket_type();
 	len = t->length + smbios_string_table_len(t->eos);
+	if (cpu_have_cpuid() && cpuid_get_max_func() >= 0x16) {
+		t->max_speed = cpuid_ebx(0x16);
+		t->current_speed = cpuid_eax(0x16); /* base frequency */
+	} else {
+		t->max_speed = smbios_cpu_get_max_speed_mhz();
+		t->current_speed = smbios_cpu_get_current_speed_mhz();
+	}
 	*current += len;
 	return len;
 }

src/include/smbios.h

@@ -53,6 +53,9 @@ const char *smbios_system_version(void);
 void smbios_system_set_uuid(u8 *uuid);
 const char *smbios_system_sku(void);
 
+unsigned int smbios_cpu_get_max_speed_mhz(void);
+unsigned int smbios_cpu_get_current_speed_mhz(void);
+
 const char *smbios_mainboard_manufacturer(void);
 const char *smbios_mainboard_product_name(void);
 const char *smbios_mainboard_serial_number(void);