Warning: That file was not part of the compilation database. It may have many parsing errors.
1 | /* |
---|---|
2 | * Switch an MMU context. |
3 | * |
4 | * This file is subject to the terms and conditions of the GNU General Public |
5 | * License. See the file "COPYING" in the main directory of this archive |
6 | * for more details. |
7 | * |
8 | * Copyright (C) 2001 - 2013 Tensilica Inc. |
9 | */ |
10 | |
11 | #ifndef _XTENSA_MMU_CONTEXT_H |
12 | #define _XTENSA_MMU_CONTEXT_H |
13 | |
14 | #ifndef CONFIG_MMU |
15 | #include <asm/nommu_context.h> |
16 | #else |
17 | |
18 | #include <linux/stringify.h> |
19 | #include <linux/sched.h> |
20 | #include <linux/mm_types.h> |
21 | #include <linux/pgtable.h> |
22 | |
23 | #include <asm/vectors.h> |
24 | |
25 | #include <asm/cacheflush.h> |
26 | #include <asm/tlbflush.h> |
27 | #include <asm-generic/mm_hooks.h> |
28 | #include <asm-generic/percpu.h> |
29 | |
30 | #if (XCHAL_HAVE_TLBS != 1) |
31 | # error "Linux must have an MMU!" |
32 | #endif |
33 | |
34 | DECLARE_PER_CPU(unsigned long, asid_cache); |
35 | #define cpu_asid_cache(cpu) per_cpu(asid_cache, cpu) |
36 | |
37 | /* |
38 | * NO_CONTEXT is the invalid ASID value that we don't ever assign to |
39 | * any user or kernel context. We use the reserved values in the |
40 | * ASID_INSERT macro below. |
41 | * |
42 | * 0 invalid |
43 | * 1 kernel |
44 | * 2 reserved |
45 | * 3 reserved |
46 | * 4...255 available |
47 | */ |
48 | |
49 | #define NO_CONTEXT 0 |
50 | #define ASID_USER_FIRST 4 |
51 | #define ASID_MASK ((1 << XCHAL_MMU_ASID_BITS) - 1) |
52 | #define ASID_INSERT(x) (0x03020001 | (((x) & ASID_MASK) << 8)) |
53 | |
54 | void init_mmu(void); |
55 | void init_kio(void); |
56 | |
57 | static inline void set_rasid_register (unsigned long val) |
58 | { |
59 | __asm__ __volatile__ (" wsr %0, rasid\n\t" |
60 | " isync\n": : "a"(val)); |
61 | } |
62 | |
63 | static inline unsigned long get_rasid_register (void) |
64 | { |
65 | unsigned long tmp; |
66 | __asm__ __volatile__ (" rsr %0, rasid\n\t": "=a"(tmp)); |
67 | return tmp; |
68 | } |
69 | |
70 | static inline void get_new_mmu_context(struct mm_struct *mm, unsigned int cpu) |
71 | { |
72 | unsigned long asid = cpu_asid_cache(cpu); |
73 | if ((++asid & ASID_MASK) == 0) { |
74 | /* |
75 | * Start new asid cycle; continue counting with next |
76 | * incarnation bits; skipping over 0, 1, 2, 3. |
77 | */ |
78 | local_flush_tlb_all(); |
79 | asid += ASID_USER_FIRST; |
80 | } |
81 | cpu_asid_cache(cpu) = asid; |
82 | mm->context.asid[cpu] = asid; |
83 | mm->context.cpu = cpu; |
84 | } |
85 | |
86 | static inline void get_mmu_context(struct mm_struct *mm, unsigned int cpu) |
87 | { |
88 | /* |
89 | * Check if our ASID is of an older version and thus invalid. |
90 | */ |
91 | |
92 | if (mm) { |
93 | unsigned long asid = mm->context.asid[cpu]; |
94 | |
95 | if (asid == NO_CONTEXT || |
96 | ((asid ^ cpu_asid_cache(cpu)) & ~ASID_MASK)) |
97 | get_new_mmu_context(mm, cpu); |
98 | } |
99 | } |
100 | |
101 | static inline void activate_context(struct mm_struct *mm, unsigned int cpu) |
102 | { |
103 | get_mmu_context(mm, cpu); |
104 | set_rasid_register(ASID_INSERT(mm->context.asid[cpu])); |
105 | invalidate_page_directory(); |
106 | } |
107 | |
108 | /* |
109 | * Initialize the context related info for a new mm_struct |
110 | * instance. Valid cpu values are 0..(NR_CPUS-1), so initializing |
111 | * to -1 says the process has never run on any core. |
112 | */ |
113 | |
114 | #define init_new_context init_new_context |
115 | static inline int init_new_context(struct task_struct *tsk, |
116 | struct mm_struct *mm) |
117 | { |
118 | int cpu; |
119 | for_each_possible_cpu(cpu) { |
120 | mm->context.asid[cpu] = NO_CONTEXT; |
121 | } |
122 | mm->context.cpu = -1; |
123 | return 0; |
124 | } |
125 | |
126 | static inline void switch_mm(struct mm_struct *prev, struct mm_struct *next, |
127 | struct task_struct *tsk) |
128 | { |
129 | unsigned int cpu = smp_processor_id(); |
130 | int migrated = next->context.cpu != cpu; |
131 | /* Flush the icache if we migrated to a new core. */ |
132 | if (migrated) { |
133 | __invalidate_icache_all(); |
134 | next->context.cpu = cpu; |
135 | } |
136 | if (migrated || prev != next) |
137 | activate_context(mm: next, cpu); |
138 | } |
139 | |
140 | /* |
141 | * Destroy context related info for an mm_struct that is about |
142 | * to be put to rest. |
143 | */ |
144 | #define destroy_context destroy_context |
145 | static inline void destroy_context(struct mm_struct *mm) |
146 | { |
147 | invalidate_page_directory(); |
148 | } |
149 | |
150 | |
151 | #include <asm-generic/mmu_context.h> |
152 | |
153 | #endif /* CONFIG_MMU */ |
154 | #endif /* _XTENSA_MMU_CONTEXT_H */ |
155 |
Warning: That file was not part of the compilation database. It may have many parsing errors.