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
10 extern int __cpu_suspend(unsigned long, int (*)(unsigned long));
11 extern 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 */
__cpu_suspend_save(u32 * ptr,u32 ptrsz,u32 sp,u32 * save_ptr)18 void __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 */
cpu_suspend(unsigned long arg,int (* fn)(unsigned long))39 int 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 }
61