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
12static inline int
13init_new_context(struct task_struct *tsk, struct mm_struct *mm)
14{
15	mm->context.id = 0;
16	return 0;
17}
18
19#define destroy_context(mm)	do { } while(0)
20
21#define CID_BITS	9
22extern spinlock_t cid_lock;
23extern unsigned int cpu_last_cid;
24
25static inline void __new_context(struct mm_struct *mm)
26{
27	unsigned int cid;
28	unsigned long flags;
29
30	spin_lock_irqsave(&cid_lock, flags);
31	cid = cpu_last_cid;
32	cpu_last_cid += 1 << TLB_MISC_offCID;
33	if (cpu_last_cid == 0)
34		cpu_last_cid = 1 << TLB_MISC_offCID << CID_BITS;
35
36	if ((cid & TLB_MISC_mskCID) == 0)
37		flush_tlb_all();
38	spin_unlock_irqrestore(&cid_lock, flags);
39
40	mm->context.id = cid;
41}
42
43static inline void check_context(struct mm_struct *mm)
44{
45	if (unlikely
46	    ((mm->context.id ^ cpu_last_cid) >> TLB_MISC_offCID >> CID_BITS))
47		__new_context(mm);
48}
49
50static inline void enter_lazy_tlb(struct mm_struct *mm, struct task_struct *tsk)
51{
52}
53
54static inline void switch_mm(struct mm_struct *prev, struct mm_struct *next,
55			     struct task_struct *tsk)
56{
57	unsigned int cpu = smp_processor_id();
58
59	if (!cpumask_test_and_set_cpu(cpu, mm_cpumask(next)) || prev != next) {
60		check_context(next);
61		cpu_switch_mm(next);
62	}
63}
64
65#define deactivate_mm(tsk,mm)	do { } while (0)
66#define activate_mm(prev,next)	switch_mm(prev, next, NULL)
67
68#endif
69