i82801dx/gx/ix/jx: Add low-memory backup for S3 path

SMM relocation code overwrite low memory owned by OS.

Change-Id: Ifa3d28bed3d3db65b0707bde62ae2b424a231f1a
Signed-off-by: Kyösti Mälkki <kyosti.malkki@gmail.com>
Reviewed-on: https://review.coreboot.org/19405
Reviewed-by: Arthur Heymans <arthur@aheymans.xyz>
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
Reviewed-by: Aaron Durbin <adurbin@chromium.org>

src/arch/x86/include/arch/cpu.h

@@ -163,6 +163,7 @@ int cpu_cpuid_extended_level(void);
 int cpu_have_cpuid(void);
 
 void smm_init(void);
+void smm_init_completion(void);
 void smm_lock(void);
 void smm_setup_structures(void *gnvs, void *tcg, void *smi1);
 

src/cpu/x86/lapic/lapic_cpu_init.c

@@ -587,6 +587,8 @@ void initialize_cpus(struct bus *cpu_bus)
 		}
 	}
 
+	smm_init_completion();
+
 	if (is_smp_boot())
 		recover_lowest_1M();
 }
@@ -595,3 +597,7 @@ void initialize_cpus(struct bus *cpu_bus)
 __attribute__((weak)) void smm_init(void)
 {
 }
+
+__attribute__((weak)) void smm_init_completion(void)
+{
+}

src/southbridge/intel/i82801dx/smi.c

@@ -18,6 +18,7 @@
 #include <device/device.h>
 #include <device/pci.h>
 #include <console/console.h>
+#include <arch/acpi.h>
 #include <arch/io.h>
 #include <cpu/cpu.h>
 #include <cpu/x86/cache.h>
@@ -229,6 +230,7 @@ static void smi_set_eos(void)
 }
 
 extern uint8_t smm_relocation_start, smm_relocation_end;
+static void *default_smm_area = NULL;
 
 static void smm_relocate(void)
 {
@@ -246,6 +248,8 @@ static void smm_relocate(void)
 		return;
 	}
 
+	default_smm_area = backup_default_smm_area();
+
 	/* copy the SMM relocation code */
 	memcpy((void *)0x38000, &smm_relocation_start,
 			&smm_relocation_end - &smm_relocation_start);
@@ -339,6 +343,11 @@ void smm_init(void)
 	smi_set_eos();
 }
 
+void smm_init_completion(void)
+{
+	restore_default_smm_area(default_smm_area);
+}
+
 void smm_lock(void)
 {
 	/* LOCK the SMM memory window and enable normal SMM.

src/southbridge/intel/i82801gx/smi.c

@@ -287,6 +287,7 @@ static void smi_set_eos(void)
 }
 
 extern uint8_t smm_relocation_start, smm_relocation_end;
+static void *default_smm_area = NULL;
 
 static void smm_relocate(void)
 {
@@ -304,6 +305,8 @@ static void smm_relocate(void)
 		return;
 	}
 
+	default_smm_area = backup_default_smm_area();
+
 	/* copy the SMM relocation code */
 	memcpy((void *)0x38000, &smm_relocation_start,
 			&smm_relocation_end - &smm_relocation_start);
@@ -412,6 +415,11 @@ void smm_init(void)
 	smi_set_eos();
 }
 
+void smm_init_completion(void)
+{
+	restore_default_smm_area(default_smm_area);
+}
+
 void smm_lock(void)
 {
 	/* LOCK the SMM memory window and enable normal SMM.

src/southbridge/intel/i82801ix/smi.c

@@ -234,6 +234,7 @@ static void smi_set_eos(void)
 }
 
 extern uint8_t smm_relocation_start, smm_relocation_end;
+static void *default_smm_area = NULL;
 
 static void smm_relocate(void)
 {
@@ -251,6 +252,8 @@ static void smm_relocate(void)
 		return;
 	}
 
+	default_smm_area = backup_default_smm_area();
+
 	/* copy the SMM relocation code */
 	memcpy((void *)0x38000, &smm_relocation_start,
 			&smm_relocation_end - &smm_relocation_start);
@@ -354,6 +357,11 @@ void smm_init(void)
 	smi_set_eos();
 }
 
+void smm_init_completion(void)
+{
+	restore_default_smm_area(default_smm_area);
+}
+
 void smm_lock(void)
 {
 	/* LOCK the SMM memory window and enable normal SMM.

src/southbridge/intel/i82801jx/smi.c

@@ -234,6 +234,7 @@ static void smi_set_eos(void)
 }
 
 extern uint8_t smm_relocation_start, smm_relocation_end;
+static void *default_smm_area = NULL;
 
 static void smm_relocate(void)
 {
@@ -251,6 +252,8 @@ static void smm_relocate(void)
 		return;
 	}
 
+	default_smm_area = backup_default_smm_area();
+
 	/* copy the SMM relocation code */
 	memcpy((void *)0x38000, &smm_relocation_start,
 			&smm_relocation_end - &smm_relocation_start);
@@ -354,6 +357,11 @@ void smm_init(void)
 	smi_set_eos();
 }
 
+void smm_init_completion(void)
+{
+	restore_default_smm_area(default_smm_area);
+}
+
 void smm_lock(void)
 {
 	/* LOCK the SMM memory window and enable normal SMM.