blob: ed4160b64e66b03d607cd2cf00b9cdac425a8395 (
plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
|
#include <linux/init.h>
#include <asm/pgalloc.h>
#include <asm/pgtable.h>
#include <asm/memory.h>
#include <asm/suspend.h>
#include <asm/tlbflush.h>
static pgd_t *suspend_pgd;
extern int __cpu_suspend(int, long, unsigned long, int (*)(unsigned long));
extern void cpu_resume_mmu(void);
/*
* Hide the first two arguments to __cpu_suspend - these are an implementation
* detail which platform code shouldn't have to know about.
*/
int cpu_suspend(unsigned long arg, int (*fn)(unsigned long))
{
struct mm_struct *mm = current->active_mm;
int ret;
if (!suspend_pgd)
return -EINVAL;
/*
* Provide a temporary page table with an identity mapping for
* the MMU-enable code, required for resuming. On successful
* resume (indicated by a zero return code), we need to switch
* back to the correct page tables.
*/
ret = __cpu_suspend(virt_to_phys(suspend_pgd),
PHYS_OFFSET - PAGE_OFFSET, arg, fn);
if (ret == 0) {
cpu_switch_mm(mm->pgd, mm);
local_flush_tlb_all();
}
return ret;
}
static int __init cpu_suspend_init(void)
{
suspend_pgd = pgd_alloc(&init_mm);
if (suspend_pgd) {
unsigned long addr = virt_to_phys(cpu_resume_mmu);
identity_mapping_add(suspend_pgd, addr, addr + SECTION_SIZE);
}
return suspend_pgd ? 0 : -ENOMEM;
}
core_initcall(cpu_suspend_init);
|