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domain.h
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1 /*
2  * arch/arm/include/asm/domain.h
3  *
4  * Copyright (C) 1999 Russell King.
5  *
6  * This program is free software; you can redistribute it and/or modify
7  * it under the terms of the GNU General Public License version 2 as
8  * published by the Free Software Foundation.
9  */
10 #ifndef __ASM_PROC_DOMAIN_H
11 #define __ASM_PROC_DOMAIN_H
12 
13 #ifndef __ASSEMBLY__
14 #include <asm/barrier.h>
15 #endif
16 
17 /*
18  * Domain numbers
19  *
20  * DOMAIN_IO - domain 2 includes all IO only
21  * DOMAIN_USER - domain 1 includes all user memory only
22  * DOMAIN_KERNEL - domain 0 includes all kernel memory only
23  *
24  * The domain numbering depends on whether we support 36 physical
25  * address for I/O or not. Addresses above the 32 bit boundary can
26  * only be mapped using supersections and supersections can only
27  * be set for domain 0. We could just default to DOMAIN_IO as zero,
28  * but there may be systems with supersection support and no 36-bit
29  * addressing. In such cases, we want to map system memory with
30  * supersections to reduce TLB misses and footprint.
31  *
32  * 36-bit addressing and supersections are only available on
33  * CPUs based on ARMv6+ or the Intel XSC3 core.
34  */
35 #ifndef CONFIG_IO_36
36 #define DOMAIN_KERNEL 0
37 #define DOMAIN_TABLE 0
38 #define DOMAIN_USER 1
39 #define DOMAIN_IO 2
40 #else
41 #define DOMAIN_KERNEL 2
42 #define DOMAIN_TABLE 2
43 #define DOMAIN_USER 1
44 #define DOMAIN_IO 0
45 #endif
46 
47 /*
48  * Domain types
49  */
50 #define DOMAIN_NOACCESS 0
51 #define DOMAIN_CLIENT 1
52 #ifdef CONFIG_CPU_USE_DOMAINS
53 #define DOMAIN_MANAGER 3
54 #else
55 #define DOMAIN_MANAGER 1
56 #endif
57 
58 #define domain_val(dom,type) ((type) << (2*(dom)))
59 
60 #ifndef __ASSEMBLY__
61 
62 #ifdef CONFIG_CPU_USE_DOMAINS
63 static inline void set_domain(unsigned val)
64 {
65  asm volatile(
66  "mcr p15, 0, %0, c3, c0 @ set domain"
67  : : "r" (val));
68  isb();
69 }
70 
71 #define modify_domain(dom,type) \
72  do { \
73  struct thread_info *thread = current_thread_info(); \
74  unsigned int domain = thread->cpu_domain; \
75  domain &= ~domain_val(dom, DOMAIN_MANAGER); \
76  thread->cpu_domain = domain | domain_val(dom, type); \
77  set_domain(thread->cpu_domain); \
78  } while (0)
79 
80 #else
81 static inline void set_domain(unsigned val) { }
82 static inline void modify_domain(unsigned dom, unsigned type) { }
83 #endif
84 
85 /*
86  * Generate the T (user) versions of the LDR/STR and related
87  * instructions (inline assembly)
88  */
89 #ifdef CONFIG_CPU_USE_DOMAINS
90 #define TUSER(instr) #instr "t"
91 #else
92 #define TUSER(instr) #instr
93 #endif
94 
95 #else /* __ASSEMBLY__ */
96 
97 /*
98  * Generate the T (user) versions of the LDR/STR and related
99  * instructions
100  */
101 #ifdef CONFIG_CPU_USE_DOMAINS
102 #define TUSER(instr) instr ## t
103 #else
104 #define TUSER(instr) instr
105 #endif
106 
107 #endif /* __ASSEMBLY__ */
108 
109 #endif /* !__ASM_PROC_DOMAIN_H */