arch/arm/kernel/suspend.c

#include <linux/init.h>

#include <asm/idmap.h>
#include <asm/pgalloc.h>
#include <asm/pgtable.h>
#include <asm/memory.h>
#include <asm/suspend.h>
#include <asm/tlbflush.h>

extern int __cpu_suspend(unsigned long, int (*)(unsigned long));
extern void cpu_resume_mmu(void);

void __cpu_suspend_save(u32 *ptr, u32 ptrsz, u32 sp, u32 *save_ptr)
{
	u32 *ctx = ptr;

	*save_ptr = virt_to_phys(ptr);

	
	*ptr++ = virt_to_phys(idmap_pgd);
	*ptr++ = sp;
	*ptr++ = virt_to_phys(cpu_do_resume);

	cpu_do_suspend(ptr);

	flush_cache_louis();

	__cpuc_flush_dcache_area(ctx, ptrsz);
	__cpuc_flush_dcache_area(save_ptr, sizeof(*save_ptr));

	outer_clean_range(*save_ptr, *save_ptr + ptrsz);
	outer_clean_range(virt_to_phys(save_ptr),
			  virt_to_phys(save_ptr) + sizeof(*save_ptr));
}

int cpu_suspend(unsigned long arg, int (*fn)(unsigned long))
{
	struct mm_struct *mm = current->active_mm;
	int ret;

	if (!idmap_pgd)
		return -EINVAL;

	ret = __cpu_suspend(arg, fn);
	if (ret == 0) {
		cpu_switch_mm(mm->pgd, mm);
		local_flush_tlb_all();
	}

	return ret;
}