soc/cavium/cn81xx: Fix minor things

* Move cbmem.c to cn81xx folder
* Store CBMEM below 4 GiB
* Make sure CBMEM doesn't overlap with ATF scratchpad
* Fix ATF scratchpad not marked as reserved due to wrong calculation
* The scratchpad is the last 1 MiB at the end of DRAM.

Tested on Cavium CN81xx EVB:
The ATF scratchpad is now marked reserved and the configuration tables
are located below 4 GiB. Linux still boots.

Change-Id: Ibbc8b586f04bd6867c045f5546b32a77c057ac74
Signed-off-by: Patrick Rudolph <patrick.rudolph@9elements.com>
Reviewed-on: https://review.coreboot.org/27955
Reviewed-by: Philipp Deppenwiese <zaolin.daisuki@gmail.com>
Reviewed-by: Paul Menzel <paulepanter@users.sourceforge.net>
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>

1 files changed, 27 insertions, 0 deletions

diff --git a/src/soc/cavium/cn81xx/cbmem.c b/src/soc/cavium/cn81xx/cbmem.c
new file mode 100644
index 0000000000..397fd263d7
--- /dev/null
+++ b/src/soc/cavium/cn81xx/cbmem.c
@@ -0,0 +1,27 @@
+/*
+ * This file is part of the coreboot project.
+ *
+ * Copyright 2014 Rockchip 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 <cbmem.h>
+#include <soc/addressmap.h>
+#include <soc/sdram.h>
+#include <stdlib.h>
+#include <symbols.h>
+
+void *cbmem_top(void)
+{
+	/* Make sure not to overlap with reserved ATF scratchpad */
+	return (void *)min((uintptr_t)_dram + (sdram_size_mb() - 1) * MiB,
+			   4ULL * GiB);
+}