m68k: Add kexec support

Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>

1 files changed, 58 insertions, 0 deletions

diff --git a/arch/m68k/kernel/machine_kexec.c b/arch/m68k/kernel/machine_kexec.c
new file mode 100644
index 000000000000..d4affc917d9d
--- /dev/null
+++ b/arch/m68k/kernel/machine_kexec.c
@@ -0,0 +1,58 @@
+/*
+ * machine_kexec.c - handle transition of Linux booting another kernel
+ */
+#include <linux/compiler.h>
+#include <linux/kexec.h>
+#include <linux/mm.h>
+#include <linux/delay.h>
+
+#include <asm/cacheflush.h>
+#include <asm/page.h>
+#include <asm/setup.h>
+
+extern const unsigned char relocate_new_kernel[];
+extern const size_t relocate_new_kernel_size;
+
+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)
+{
+}
+
+typedef void (*relocate_kernel_t)(unsigned long ptr,
+				  unsigned long start,
+				  unsigned long cpu_mmu_flags) __noreturn;
+
+void machine_kexec(struct kimage *image)
+{
+	void *reboot_code_buffer;
+	unsigned long cpu_mmu_flags;
+
+	reboot_code_buffer = page_address(image->control_code_page);
+
+	memcpy(reboot_code_buffer, relocate_new_kernel,
+	       relocate_new_kernel_size);
+
+	/*
+	 * we do not want to be bothered.
+	 */
+	local_irq_disable();
+
+	pr_info("Will call new kernel at 0x%08lx. Bye...\n", image->start);
+	__flush_cache_all();
+	cpu_mmu_flags = m68k_cputype | m68k_mmutype << 8;
+	((relocate_kernel_t) reboot_code_buffer)(image->head & PAGE_MASK,
+						 image->start,
+						 cpu_mmu_flags);
+}