POST: OCM test added.

Added OCM test to POST layer. This version runs before all other tests
but doesn't yet interrupt post sequence on failure.

Signed-off-by: Ilya Yanok <yanok@emcraft.com>
Signed-off-by: Yuri Tikhonov <yur@emcraft.com>
diff --git a/post/cpu/ppc4xx/Makefile b/post/cpu/ppc4xx/Makefile
index f19dc5d..1cfd3bb 100644
--- a/post/cpu/ppc4xx/Makefile
+++ b/post/cpu/ppc4xx/Makefile
@@ -29,6 +29,7 @@
 COBJS-$(CONFIG_HAS_POST)	+= denali_ecc.o
 COBJS-$(CONFIG_HAS_POST)	+= ether.o
 COBJS-$(CONFIG_HAS_POST)	+= fpu.o
+COBJS-$(CONFIG_HAS_POST)	+= ocm.o
 COBJS-$(CONFIG_HAS_POST)	+= spr.o
 COBJS-$(CONFIG_HAS_POST)	+= uart.o
 COBJS-$(CONFIG_HAS_POST)	+= watchdog.o
diff --git a/post/cpu/ppc4xx/ocm.c b/post/cpu/ppc4xx/ocm.c
new file mode 100644
index 0000000..88aa93e
--- /dev/null
+++ b/post/cpu/ppc4xx/ocm.c
@@ -0,0 +1,89 @@
+/*
+ * (C) Copyright 2008 Ilya Yanok, EmCraft Systems, yanok@emcraft.com
+ *
+ * Developed for DENX Software Engineering GmbH
+ *
+ * See file CREDITS for list of people who contributed to this
+ * project.
+ *
+ * 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; either version 2 of
+ * the License, or (at your option) any later version.
+ *
+ * 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., 59 Temple Place, Suite 330, Boston,
+ * MA 02111-1307 USA
+ */
+#include <common.h>
+
+/*
+ * This test attempts to verify on-chip memory (OCM). Result is written
+ * to the scratch register and if test succeed it won't be run till next
+ * power on.
+ */
+
+#include <post.h>
+
+#include <asm/io.h>
+
+DECLARE_GLOBAL_DATA_PTR;
+
+#define OCM_TEST_PATTERN1	0x55555555
+#define OCM_TEST_PATTERN2	0xAAAAAAAA
+
+#if CONFIG_POST & CFG_POST_OCM
+
+static uint ocm_status_read(void)
+{
+	return in_be32((void *)CFG_OCM_STATUS_ADDR) &
+		CFG_OCM_STATUS_MASK;
+}
+
+static void ocm_status_write(uint value)
+{
+	out_be32((void *)CFG_OCM_STATUS_ADDR, value |
+		(in_be32((void *)CFG_OCM_STATUS_ADDR) &
+			~CFG_OCM_STATUS_MASK));
+}
+
+static inline int ocm_test_word(uint value, uint *address)
+{
+	uint read_value;
+
+	*address = value;
+	sync();
+	read_value = *address;
+
+	return (read_value != value);
+}
+
+int ocm_post_test(int flags)
+{
+	uint   old_value;
+	int    ret = 0;
+	uint  *address = (uint*)CFG_OCM_BASE;
+
+	if (ocm_status_read() == CFG_OCM_STATUS_OK)
+		return 0;
+	for (; address < (uint*)(CFG_OCM_BASE + CFG_OCM_SIZE); address++) {
+		old_value = *address;
+		if (ocm_test_word(OCM_TEST_PATTERN1, address) ||
+				ocm_test_word(OCM_TEST_PATTERN2, address)) {
+			ret = 1;
+			*address = old_value;
+			printf("OCM POST failed at %p!\n", address);
+			break;
+		}
+		*address = old_value;
+	}
+	ocm_status_write(ret ? CFG_OCM_STATUS_FAIL : CFG_OCM_STATUS_OK);
+	return ret;
+}
+#endif /* CONFIG_POST & CFG_POST_OCM */