[PATCH] sh: kexec() support

This adds kexec() support for SH.

Signed-off-by: kogiidena <kogiidena@eggplant.ddo.jp>
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
Cc: <fastboot@lists.osdl.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

1 files changed, 112 insertions, 0 deletions

diff --git a/arch/sh/kernel/machine_kexec.c b/arch/sh/kernel/machine_kexec.c
new file mode 100644
index 000000000000..43546525f28f
--- /dev/null
+++ b/arch/sh/kernel/machine_kexec.c
@@ -0,0 +1,112 @@
+/*
+ * machine_kexec.c - handle transition of Linux booting another kernel
+ * Copyright (C) 2002-2003 Eric Biederman  <ebiederm@xmission.com>
+ *
+ * GameCube/ppc32 port Copyright (C) 2004 Albert Herranz
+ * LANDISK/sh4 supported by kogiidena
+ *
+ * This source code is licensed under the GNU General Public License,
+ * Version 2.  See the file COPYING for more details.
+ */
+
+#include <linux/mm.h>
+#include <linux/kexec.h>
+#include <linux/delay.h>
+#include <linux/reboot.h>
+#include <asm/pgtable.h>
+#include <asm/pgalloc.h>
+#include <asm/mmu_context.h>
+#include <asm/io.h>
+#include <asm/cacheflush.h>
+
+typedef NORET_TYPE void (*relocate_new_kernel_t)(
+				unsigned long indirection_page,
+				unsigned long reboot_code_buffer,
+				unsigned long start_address,
+				unsigned long vbr_reg) ATTRIB_NORET;
+
+const extern unsigned char relocate_new_kernel[];
+const extern unsigned int relocate_new_kernel_size;
+extern void *gdb_vbr_vector;
+
+/*
+ * Provide a dummy crash_notes definition while crash dump arrives to ppc.
+ * This prevents breakage of crash_notes attribute in kernel/ksysfs.c.
+ */
+void *crash_notes = NULL;
+
+void machine_shutdown(void)
+{
+}
+
+void machine_crash_shutdown(struct pt_regs *regs)
+{
+}
+
+/*
+ * Do what every setup is needed on image and the
+ * reboot code buffer to allow us to avoid allocations
+ * later.
+ */
+int machine_kexec_prepare(struct kimage *image)
+{
+	return 0;
+}
+
+void machine_kexec_cleanup(struct kimage *image)
+{
+}
+
+static void kexec_info(struct kimage *image)
+{
+        int i;
+	printk("kexec information\n");
+	for (i = 0; i < image->nr_segments; i++) {
+	        printk("  segment[%d]: 0x%08x - 0x%08x (0x%08x)\n",
+		       i,
+		       (unsigned int)image->segment[i].mem,
+		       (unsigned int)image->segment[i].mem + image->segment[i].memsz,
+		       (unsigned int)image->segment[i].memsz);
+ 	}
+	printk("  start     : 0x%08x\n\n", (unsigned int)image->start);
+}
+
+
+/*
+ * Do not allocate memory (or fail in any way) in machine_kexec().
+ * We are past the point of no return, committed to rebooting now.
+ */
+NORET_TYPE void machine_kexec(struct kimage *image)
+{
+
+	unsigned long page_list;
+	unsigned long reboot_code_buffer;
+	unsigned long vbr_reg;
+	relocate_new_kernel_t rnk;
+
+#if defined(CONFIG_SH_STANDARD_BIOS)
+	vbr_reg = ((unsigned long )gdb_vbr_vector) - 0x100;
+#else
+	vbr_reg = 0x80000000;  // dummy
+#endif
+	/* Interrupts aren't acceptable while we reboot */
+	local_irq_disable();
+
+	page_list = image->head;
+
+	/* we need both effective and real address here */
+	reboot_code_buffer =
+			(unsigned long)page_address(image->control_code_page);
+
+	/* copy our kernel relocation code to the control code page */
+	memcpy((void *)reboot_code_buffer, relocate_new_kernel,
+						relocate_new_kernel_size);
+
+        kexec_info(image);
+	flush_cache_all();
+
+	/* now call it */
+	rnk = (relocate_new_kernel_t) reboot_code_buffer;
+       	(*rnk)(page_list, reboot_code_buffer, image->start, vbr_reg);
+}
+