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-rw-r--r--src/arch/x86/ebda.c52
1 files changed, 52 insertions, 0 deletions
diff --git a/src/arch/x86/ebda.c b/src/arch/x86/ebda.c
new file mode 100644
index 0000000000..47dfbdb1e9
--- /dev/null
+++ b/src/arch/x86/ebda.c
@@ -0,0 +1,52 @@
+/*
+ * This file is part of the coreboot project.
+ *
+ * Copyright (C) 2012 The Chromium OS Authors. All rights reserved.
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License as
+ * published by the Free Software Foundation; version 2 of
+ * the License.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc.
+ */
+
+#include <stdint.h>
+#include <string.h>
+#include <arch/io.h>
+#include <arch/ebda.h>
+#include <arch/acpi.h>
+
+void setup_ebda(u32 low_memory_size, u16 ebda_segment, u16 ebda_size)
+{
+ /* Skip in S3 resume path */
+ if (acpi_is_wakeup_s3())
+ return;
+
+ if (!low_memory_size || !ebda_segment || !ebda_size)
+ return;
+
+ /* clear BIOS DATA AREA */
+ memset((void *)X86_BDA_BASE, 0, X86_BDA_SIZE);
+
+ write16(X86_EBDA_LOWMEM, (low_memory_size >> 10));
+ write16(X86_EBDA_SEGMENT, ebda_segment);
+
+ /* Set up EBDA */
+ memset((void *)((uintptr_t)ebda_segment << 4), 0, ebda_size);
+ write16((void*)((uintptr_t)ebda_segment << 4), (ebda_size >> 10));
+}
+
+void setup_default_ebda(void)
+{
+ setup_ebda(DEFAULT_EBDA_LOWMEM,
+ DEFAULT_EBDA_SEGMENT,
+ DEFAULT_EBDA_SIZE);
+}