1 /* SPDX-License-Identifier: GPL-2.0 */
2 // Copyright (C) 2005-2017 Andes Technology Corporation
3 
4 #ifndef __ASM_NDS32_MMU_CONTEXT_H
5 #define __ASM_NDS32_MMU_CONTEXT_H
6 
7 #include <linux/spinlock.h>
8 #include <asm/tlbflush.h>
9 #include <asm/proc-fns.h>
10 #include <asm-generic/mm_hooks.h>
11 
12 #define init_new_context init_new_context
13 static inline int
init_new_context(struct task_struct * tsk,struct mm_struct * mm)14 init_new_context(struct task_struct *tsk, struct mm_struct *mm)
15 {
16 	mm->context.id = 0;
17 	return 0;
18 }
19 
20 #define CID_BITS	9
21 extern spinlock_t cid_lock;
22 extern unsigned int cpu_last_cid;
23 
__new_context(struct mm_struct * mm)24 static inline void __new_context(struct mm_struct *mm)
25 {
26 	unsigned int cid;
27 	unsigned long flags;
28 
29 	spin_lock_irqsave(&cid_lock, flags);
30 	cid = cpu_last_cid;
31 	cpu_last_cid += 1 << TLB_MISC_offCID;
32 	if (cpu_last_cid == 0)
33 		cpu_last_cid = 1 << TLB_MISC_offCID << CID_BITS;
34 
35 	if ((cid & TLB_MISC_mskCID) == 0)
36 		flush_tlb_all();
37 	spin_unlock_irqrestore(&cid_lock, flags);
38 
39 	mm->context.id = cid;
40 }
41 
check_context(struct mm_struct * mm)42 static inline void check_context(struct mm_struct *mm)
43 {
44 	if (unlikely
45 	    ((mm->context.id ^ cpu_last_cid) >> TLB_MISC_offCID >> CID_BITS))
46 		__new_context(mm);
47 }
48 
switch_mm(struct mm_struct * prev,struct mm_struct * next,struct task_struct * tsk)49 static inline void switch_mm(struct mm_struct *prev, struct mm_struct *next,
50 			     struct task_struct *tsk)
51 {
52 	unsigned int cpu = smp_processor_id();
53 
54 	if (!cpumask_test_and_set_cpu(cpu, mm_cpumask(next)) || prev != next) {
55 		check_context(next);
56 		cpu_switch_mm(next);
57 	}
58 }
59 
60 #include <asm-generic/mmu_context.h>
61 
62 #endif
63