CBMEM: Do not use get_top_of_ram() with DYNAMIC_CBMEM

The name was always obscure and confusing. Instead define cbmem_top()
directly in the chipset code for x86 like on ARMs.

TODO: Check TSEG alignment, it used for MTRR programming.

Change-Id: Ibbe5f05ab9c7d87d09caa673766cd17d192cd045
Signed-off-by: Kyösti Mälkki <kyosti.malkki@gmail.com>
Reviewed-on: http://review.coreboot.org/7888
Tested-by: build bot (Jenkins)
Reviewed-by: Aaron Durbin <adurbin@google.com>

1 files changed, 20 insertions, 2 deletions

diff --git a/src/soc/intel/fsp_baytrail/memmap.c b/src/soc/intel/fsp_baytrail/memmap.c
index 83858b89a8..615916b96d 100644
--- a/src/soc/intel/fsp_baytrail/memmap.c
+++ b/src/soc/intel/fsp_baytrail/memmap.c
@@ -2,6 +2,7 @@
  * This file is part of the coreboot project.
  *
  * Copyright (C) 2013 Google, Inc.
+ * Copyright (C) 2014 Sage Electronic Engineering, LLC.
  *
  * 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
@@ -21,8 +22,25 @@
 #include <cbmem.h>
 #include <baytrail/iosf.h>
 #include <baytrail/smm.h>
+#include <drivers/intel/fsp/fsp_util.h>
 
-void *smm_region_start(void)
+uintptr_t smm_region_start(void)
 {
-	return (void *)(iosf_bunit_read(BUNIT_SMRRL) << 20);
+	return (iosf_bunit_read(BUNIT_SMRRL) << 20);
+}
+
+/*
+ * Calculate the top of usable (low) DRAM.
+ * The FSP's reserved memory sits just below the SMM region,
+ * allowing calculation of the top of usable memory.
+ *
+ * The entire memory map is shown in northcluster.c
+ */
+
+void *cbmem_top(void)
+{
+	uintptr_t tom = smm_region_start();
+	if (!tom)
+		tom = iosf_bunit_read(BUNIT_BMBOUND);
+	return (void *) tom - FSP_RESERVE_MEMORY_SIZE;
 }