ppc64 kdump purgatory backup support

This patch implements the purgatory support to take backup
of the first 32KB of the first kernel
- Modified the v2wrap code to make the secondary cpus spin
directly in the v2wrap after pulling them out of kexec_wait
- Use the elf_rel function support to set the various
symbols used in purgatory
- load device-tree as a separate segment
- other miscellaneous compiler warnings cleanup
- add purgatory code support for backup
- build purgatory as relocatable for ppc64

Signed-off-by: R Sharada <sharada@in.ibm.com>
Signed-off-by: Mohan Kumar M <mohan@in.ibm.com>
Signed-off-by: Maneesh Soni <maneesh@in.ibm.com>

1 files changed, 41 insertions, 0 deletions

diff --git a/purgatory/arch/ppc64/crashdump_backup.c b/purgatory/arch/ppc64/crashdump_backup.c
new file mode 100644
index 0000000..07f7847
--- /dev/null
+++ b/purgatory/arch/ppc64/crashdump_backup.c
@@ -0,0 +1,41 @@
+/*
+ * kexec: Linux boots Linux
+ *
+ * Created by: Mohan Kumar M (mohan@in.ibm.com)
+ *
+ * Copyright (C) IBM Corporation, 2005. 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., 675 Mass Ave, Cambridge, MA 02139, USA.
+ */
+
+#include <stdint.h>
+#include <string.h>
+
+#define BACKUP_REGION_SOURCE 0x0
+#define BACKUP_REGION_SIZE 32*1024
+
+extern unsigned long backup_start;
+
+/* Backup first 32KB of memory to backup region reserved by kexec */
+void crashdump_backup_memory(void)
+{
+	void *dest, *src;
+
+	src = (void *)BACKUP_REGION_SOURCE;
+
+	if (backup_start) {
+		dest = (void *)(backup_start);
+		memcpy(dest, src, BACKUP_REGION_SIZE);
+	}
+}