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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 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 | // SPDX-License-Identifier: GPL-2.0 #include <linux/init.h> #include <linux/slab.h> #include <linux/mm_types.h> #include <asm/cacheflush.h> #include <asm/idmap.h> #include <asm/pgalloc.h> #include <asm/pgtable.h> #include <asm/memory.h> #include <asm/smp_plat.h> #include <asm/suspend.h> #include <asm/tlbflush.h> extern int __cpu_suspend(unsigned long, int (*)(unsigned long), u32 cpuid); extern void cpu_resume_mmu(void); #ifdef CONFIG_MMU int cpu_suspend(unsigned long arg, int (*fn)(unsigned long)) { struct mm_struct *mm = current->active_mm; u32 __mpidr = cpu_logical_map(smp_processor_id()); int ret; if (!idmap_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(arg, fn, __mpidr); if (ret == 0) { cpu_switch_mm(mm->pgd, mm); local_flush_bp_all(); local_flush_tlb_all(); } return ret; } #else int cpu_suspend(unsigned long arg, int (*fn)(unsigned long)) { u32 __mpidr = cpu_logical_map(smp_processor_id()); return __cpu_suspend(arg, fn, __mpidr); } #define idmap_pgd NULL #endif /* * This is called by __cpu_suspend() to save the state, and do whatever * flushing is required to ensure that when the CPU goes to sleep we have * the necessary data available when the caches are not searched. */ void __cpu_suspend_save(u32 *ptr, u32 ptrsz, u32 sp, u32 *save_ptr) { u32 *ctx = ptr; *save_ptr = virt_to_phys(ptr); /* This must correspond to the LDM in cpu_resume() assembly */ *ptr++ = virt_to_phys(idmap_pgd); *ptr++ = sp; *ptr++ = virt_to_phys(cpu_do_resume); cpu_do_suspend(ptr); flush_cache_louis(); /* * flush_cache_louis does not guarantee that * save_ptr and ptr are cleaned to main memory, * just up to the Level of Unification Inner Shareable. * Since the context pointer and context itself * are to be retrieved with the MMU off that * data must be cleaned from all cache levels * to main memory using "area" cache primitives. */ __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)); } extern struct sleep_save_sp sleep_save_sp; static int cpu_suspend_alloc_sp(void) { void *ctx_ptr; /* ctx_ptr is an array of physical addresses */ ctx_ptr = kcalloc(mpidr_hash_size(), sizeof(u32), GFP_KERNEL); if (WARN_ON(!ctx_ptr)) return -ENOMEM; sleep_save_sp.save_ptr_stash = ctx_ptr; sleep_save_sp.save_ptr_stash_phys = virt_to_phys(ctx_ptr); sync_cache_w(&sleep_save_sp); return 0; } early_initcall(cpu_suspend_alloc_sp); |