From 2e50142f62c20c437100ac3a1a1a50720a31a9d6 Mon Sep 17 00:00:00 2001
From: Kyösti Mälkki <kyosti.malkki@gmail.com>
Date: Fri, 21 Apr 2017 08:43:09 +0300
Subject: i82801dx/gx/ix/jx: Add low-memory backup for S3 path
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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/southbridge/intel/i82801dx/smi.c | 9 +++++++++
 1 file changed, 9 insertions(+)

(limited to 'src/southbridge/intel/i82801dx')

diff --git a/src/southbridge/intel/i82801dx/smi.c b/src/southbridge/intel/i82801dx/smi.c
index 93e28452e0..945fcf2db8 100644
--- a/src/southbridge/intel/i82801dx/smi.c
+++ b/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.
-- 
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