3 files changed, 58 insertions, 1 deletions

diff --git a/src/cpu/intel/model_106cx/Kconfig b/src/cpu/intel/model_106cx/Kconfig
index 09acfd93f8..a005ba21da 100644
--- a/src/cpu/intel/model_106cx/Kconfig
+++ b/src/cpu/intel/model_106cx/Kconfig
@@ -11,6 +11,7 @@ config CPU_INTEL_MODEL_106CX
 	select AP_IN_SIPI_WAIT
 	select TSC_SYNC_MFENCE
 	select SUPPORT_CPU_UCODE_IN_CBFS
+	select SERIALIZED_SMM_INITIALIZATION
 
 if CPU_INTEL_MODEL_106CX
 
diff --git a/src/cpu/x86/Kconfig b/src/cpu/x86/Kconfig
index 131cbf24bb..94225a3807 100644
--- a/src/cpu/x86/Kconfig
+++ b/src/cpu/x86/Kconfig
@@ -96,6 +96,17 @@ config SMM_LAPIC_REMAP_MITIGATION
 	default y if NORTHBRIDGE_INTEL_NEHALEM
 	default n
 
+config SERIALIZED_SMM_INITIALIZATION
+	bool
+	default n
+	help
+	  On some CPUs, there is a race condition in SMM.
+	  This can occur when both hyperthreads change SMM state
+	  variables in parallel without coordination.
+	  Setting this option serializes the SMM initialization
+	  to avoid an ugly hang in the boot process at the cost
+	  of a slightly longer boot time.
+
 config X86_AMD_FIXED_MTRRS
 	bool
 	default n
diff --git a/src/cpu/x86/lapic/lapic_cpu_init.c b/src/cpu/x86/lapic/lapic_cpu_init.c
index ef150a50d7..bf63517384 100644
--- a/src/cpu/x86/lapic/lapic_cpu_init.c
+++ b/src/cpu/x86/lapic/lapic_cpu_init.c
@@ -458,6 +458,39 @@ static void start_other_cpus(struct bus *cpu_bus, struct device *bsp_cpu)
 
 }
 
+static void smm_other_cpus(struct bus *cpu_bus, device_t bsp_cpu)
+{
+	device_t cpu;
+	int pre_count = atomic_read(&active_cpus);
+
+	/* Loop through the cpus once to let them run through SMM relocator */
+
+	for(cpu = cpu_bus->children; cpu ; cpu = cpu->sibling) {
+		if (cpu->path.type != DEVICE_PATH_APIC) {
+			continue;
+		}
+
+		printk(BIOS_ERR, "considering CPU 0x%02x for SMM init\n",
+			cpu->path.apic.apic_id);
+
+		if (cpu == bsp_cpu)
+			continue;
+
+		if (!cpu->enabled) {
+			continue;
+		}
+
+		if (!start_cpu(cpu)) {
+			/* Record the error in cpu? */
+			printk(BIOS_ERR, "CPU 0x%02x would not start!\n",
+				cpu->path.apic.apic_id);
+		}
+
+		/* FIXME: endless loop */
+		while (atomic_read(&active_cpus) != pre_count) ;
+	}
+}
+
 static void wait_other_cpus_stop(struct bus *cpu_bus)
 {
 	struct device *cpu;
@@ -528,7 +561,8 @@ void initialize_cpus(struct bus *cpu_bus)
 #endif
 
 #if CONFIG_HAVE_SMI_HANDLER
-	smm_init();
+	if (!IS_ENABLED(CONFIG_SERIALIZED_SMM_INITIALIZATION))
+		smm_init();
 #endif
 
 #if CONFIG_SMP && CONFIG_MAX_CPUS > 1
@@ -547,4 +581,15 @@ void initialize_cpus(struct bus *cpu_bus)
 	/* Now wait the rest of the cpus stop*/
 	wait_other_cpus_stop(cpu_bus);
 #endif
+
+	if (IS_ENABLED(CONFIG_SERIALIZED_SMM_INITIALIZATION)) {
+		/* At this point, all APs are sleeping:
+		 * smm_init() will queue a pending SMI on all cpus
+		 * and smm_other_cpus() will start them one by one */
+		smm_init();
+#if CONFIG_SMP && CONFIG_MAX_CPUS > 1
+		last_cpu_index = 0;
+		smm_other_cpus(cpu_bus, info->cpu);
+#endif
+	}
 }