1#include <linux/init.h>
 2
 3#include <asm/idmap.h>
 4#include <asm/pgalloc.h>
 5#include <asm/pgtable.h>
 6#include <asm/memory.h>
 7#include <asm/suspend.h>
 8#include <asm/tlbflush.h>
 9
10extern int __cpu_suspend(unsigned long, int (*)(unsigned long));
11extern void cpu_resume_mmu(void);
12
13/*
14 * This is called by __cpu_suspend() to save the state, and do whatever
15 * flushing is required to ensure that when the CPU goes to sleep we have
16 * the necessary data available when the caches are not searched.
17 */
18void __cpu_suspend_save(u32 *ptr, u32 ptrsz, u32 sp, u32 *save_ptr)
19{
20	*save_ptr = virt_to_phys(ptr);
21
22	/* This must correspond to the LDM in cpu_resume() assembly */
23	*ptr++ = virt_to_phys(idmap_pgd);
24	*ptr++ = sp;
25	*ptr++ = virt_to_phys(cpu_do_resume);
26
27	cpu_do_suspend(ptr);
28
29	flush_cache_all();
30	outer_clean_range(*save_ptr, *save_ptr + ptrsz);
31	outer_clean_range(virt_to_phys(save_ptr),
32			  virt_to_phys(save_ptr) + sizeof(*save_ptr));
33}
34
35/*
36 * Hide the first two arguments to __cpu_suspend - these are an implementation
37 * detail which platform code shouldn't have to know about.
38 */
39int cpu_suspend(unsigned long arg, int (*fn)(unsigned long))
40{
41	struct mm_struct *mm = current->active_mm;
42	int ret;
43
44	if (!idmap_pgd)
45		return -EINVAL;
46
47	/*
48	 * Provide a temporary page table with an identity mapping for
49	 * the MMU-enable code, required for resuming.  On successful
50	 * resume (indicated by a zero return code), we need to switch
51	 * back to the correct page tables.
52	 */
53	ret = __cpu_suspend(arg, fn);
54	if (ret == 0) {
55		cpu_switch_mm(mm->pgd, mm);
56		local_flush_tlb_all();
57	}
58
59	return ret;
60}