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 */ 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 */ 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