[MIPS] Add support for kexec

A tiny userland application loading the kernel and invoking kexec_load for 
mips is available here:

http://chac.le-poulpe.net/~nico/kexec/kexec-2006-10-18.tar.gz

Signed-off-by: Ralf Baechle <ralf@linux-mips.org>

1 files changed, 85 insertions, 0 deletions

diff --git a/arch/mips/kernel/machine_kexec.c b/arch/mips/kernel/machine_kexec.c
new file mode 100644
index 0000000..e0ad754
--- /dev/null
+++ b/arch/mips/kernel/machine_kexec.c
@@ -0,0 +1,85 @@
+/*
+ * machine_kexec.c for kexec
+ * Created by <nschichan@corp.free.fr> on Thu Oct 12 15:15:06 2006
+ *
+ * This source code is licensed under the GNU General Public License,
+ * Version 2.  See the file COPYING for more details.
+ */
+
+#include <linux/kexec.h>
+#include <linux/mm.h>
+#include <linux/delay.h>
+
+#include <asm/cacheflush.h>
+#include <asm/page.h>
+
+const extern unsigned char relocate_new_kernel[];
+const extern unsigned int relocate_new_kernel_size;
+
+extern unsigned long kexec_start_address;
+extern unsigned long kexec_indirection_page;
+
+int
+machine_kexec_prepare(struct kimage *kimage)
+{
+	return 0;
+}
+
+void
+machine_kexec_cleanup(struct kimage *kimage)
+{
+}
+
+void
+machine_shutdown(void)
+{
+}
+
+void
+machine_crash_shutdown(struct pt_regs *regs)
+{
+}
+
+void
+machine_kexec(struct kimage *image)
+{
+	unsigned long reboot_code_buffer;
+	unsigned long entry;
+	unsigned long *ptr;
+
+	reboot_code_buffer =
+	  (unsigned long)page_address(image->control_code_page);
+
+	kexec_start_address = image->start;
+	kexec_indirection_page = phys_to_virt(image->head & PAGE_MASK);
+
+	memcpy((void*)reboot_code_buffer, relocate_new_kernel,
+	       relocate_new_kernel_size);
+
+	/*
+	 * The generic kexec code builds a page list with physical
+	 * addresses. they are directly accessible through KSEG0 (or
+	 * CKSEG0 or XPHYS if on 64bit system), hence the
+	 * pys_to_virt() call.
+	 */
+	for (ptr = &image->head; (entry = *ptr) && !(entry &IND_DONE);
+	     ptr = (entry & IND_INDIRECTION) ?
+	       phys_to_virt(entry & PAGE_MASK) : ptr + 1) {
+		if (*ptr & IND_SOURCE || *ptr & IND_INDIRECTION ||
+		    *ptr & IND_DESTINATION)
+			*ptr = phys_to_virt(*ptr);
+	}
+
+	/*
+	 * we do not want to be bothered.
+	 */
+	local_irq_disable();
+
+	flush_icache_range(reboot_code_buffer,
+			   reboot_code_buffer + KEXEC_CONTROL_CODE_SIZE);
+
+	printk("Will call new kernel at %08x\n", image->start);
+	printk("Bye ...\n");
+	flush_cache_all();
+	((void (*)(void))reboot_code_buffer)();
+}