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Diffstat (limited to 'src/southbridge/amd/cimx/sb900/ramtop.c')
-rw-r--r--src/southbridge/amd/cimx/sb900/ramtop.c43
1 files changed, 43 insertions, 0 deletions
diff --git a/src/southbridge/amd/cimx/sb900/ramtop.c b/src/southbridge/amd/cimx/sb900/ramtop.c
new file mode 100644
index 0000000000..34e8364379
--- /dev/null
+++ b/src/southbridge/amd/cimx/sb900/ramtop.c
@@ -0,0 +1,43 @@
+/*
+ * This file is part of the coreboot project.
+ *
+ * Copyright (C) 2010 Advanced Micro Devices, Inc.
+ *
+ * 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.
+ */
+
+#include <stdint.h>
+#include <arch/io.h>
+#include <cbmem.h>
+#include <southbridge/amd/cimx/cimx_util.h>
+
+void backup_top_of_ram(uint64_t ramtop)
+{
+ u32 dword = ramtop;
+ int nvram_pos = 0xf8, i; /* temp */
+ for (i = 0; i < 4; i++) {
+ outb(nvram_pos, BIOSRAM_INDEX);
+ outb((dword >> (8 * i)) & 0xff, BIOSRAM_DATA);
+ nvram_pos++;
+ }
+}
+
+unsigned long get_top_of_ram(void)
+{
+ u32 xdata = 0;
+ int xnvram_pos = 0xf8, xi;
+ for (xi = 0; xi < 4; xi++) {
+ outb(xnvram_pos, BIOSRAM_INDEX);
+ xdata &= ~(0xff << (xi * 8));
+ xdata |= inb(BIOSRAM_DATA) << (xi *8);
+ xnvram_pos++;
+ }
+ return (unsigned long) xdata;
+}