sh: add kexec jump support
Add kexec jump support to the SuperH architecture.
Similar to the x86 implementation, with the following
exceptions:
- Instead of separating the assembly code flow into
two parts for regular kexec and kexec jump we use a
single code path. In the assembly snippet regular
kexec is just kexec jump that never comes back.
- Instead of using a swap page when moving data between
pages the page copy assembly routine has been modified
to exchange the data between the pages using registers.
- We walk the page list twice in machine_kexec() to
do and undo physical to virtual address conversion.
Signed-off-by: Magnus Damm <damm@igel.co.jp>
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
diff --git a/arch/sh/kernel/machine_kexec.c b/arch/sh/kernel/machine_kexec.c
index 25b4748..c44efb7 100644
--- a/arch/sh/kernel/machine_kexec.c
+++ b/arch/sh/kernel/machine_kexec.c
@@ -14,20 +14,21 @@
#include <linux/delay.h>
#include <linux/reboot.h>
#include <linux/numa.h>
+#include <linux/suspend.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) ATTRIB_NORET;
+typedef void (*relocate_new_kernel_t)(unsigned long indirection_page,
+ unsigned long reboot_code_buffer,
+ unsigned long start_address);
extern const unsigned char relocate_new_kernel[];
extern const unsigned int relocate_new_kernel_size;
extern void *gdb_vbr_vector;
+extern void *vbr_base;
void machine_shutdown(void)
{
@@ -72,7 +73,6 @@
*/
void machine_kexec(struct kimage *image)
{
-
unsigned long page_list;
unsigned long reboot_code_buffer;
relocate_new_kernel_t rnk;
@@ -92,6 +92,11 @@
*ptr = (unsigned long) phys_to_virt(*ptr);
}
+#ifdef CONFIG_KEXEC_JUMP
+ if (image->preserve_context)
+ save_processor_state();
+#endif
+
/* Interrupts aren't acceptable while we reboot */
local_irq_disable();
@@ -117,6 +122,23 @@
/* now call it */
rnk = (relocate_new_kernel_t) reboot_code_buffer;
(*rnk)(page_list, reboot_code_buffer, image->start);
+
+#ifdef CONFIG_KEXEC_JUMP
+ asm volatile("ldc %0, vbr" : : "r" (&vbr_base) : "memory");
+ local_irq_disable();
+ clear_bl_bit();
+ if (image->preserve_context)
+ restore_processor_state();
+
+ /* Convert page list back to physical addresses, what a mess. */
+ for (ptr = &image->head; (entry = *ptr) && !(entry & IND_DONE);
+ ptr = (*ptr & IND_INDIRECTION) ?
+ phys_to_virt(*ptr & PAGE_MASK) : ptr + 1) {
+ if (*ptr & IND_SOURCE || *ptr & IND_INDIRECTION ||
+ *ptr & IND_DESTINATION)
+ *ptr = virt_to_phys(*ptr);
+ }
+#endif
}
void arch_crash_save_vmcoreinfo(void)