1 /* SPDX-License-Identifier: GPL-2.0 */
2 // Copyright (C) 2018 Hangzhou C-SKY Microsystems co.,ltd.
3 
4 #ifndef __ASM_CSKY_MMU_CONTEXT_H
5 #define __ASM_CSKY_MMU_CONTEXT_H
6 
7 #include <asm-generic/mm_hooks.h>
8 #include <asm/setup.h>
9 #include <asm/page.h>
10 #include <asm/cacheflush.h>
11 #include <asm/tlbflush.h>
12 
13 #include <linux/errno.h>
14 #include <linux/sched.h>
15 #include <abi/ckmmu.h>
16 
17 #define TLBMISS_HANDLER_SETUP_PGD(pgd) \
18 	setup_pgd(__pa(pgd), false)
19 
20 #define TLBMISS_HANDLER_SETUP_PGD_KERNEL(pgd) \
21 	setup_pgd(__pa(pgd), true)
22 
23 #define ASID_MASK		((1 << CONFIG_CPU_ASID_BITS) - 1)
24 #define cpu_asid(mm)		(atomic64_read(&mm->context.asid) & ASID_MASK)
25 
26 #define init_new_context(tsk,mm)	({ atomic64_set(&(mm)->context.asid, 0); 0; })
27 #define activate_mm(prev,next)		switch_mm(prev, next, current)
28 
29 #define destroy_context(mm)		do {} while (0)
30 #define enter_lazy_tlb(mm, tsk)		do {} while (0)
31 #define deactivate_mm(tsk, mm)		do {} while (0)
32 
33 void check_and_switch_context(struct mm_struct *mm, unsigned int cpu);
34 
35 static inline void
36 switch_mm(struct mm_struct *prev, struct mm_struct *next,
37 	  struct task_struct *tsk)
38 {
39 	unsigned int cpu = smp_processor_id();
40 
41 	if (prev != next)
42 		check_and_switch_context(next, cpu);
43 
44 	TLBMISS_HANDLER_SETUP_PGD(next->pgd);
45 	write_mmu_entryhi(next->context.asid.counter);
46 
47 	flush_icache_deferred(next);
48 }
49 #endif /* __ASM_CSKY_MMU_CONTEXT_H */
50