xref: /linux/arch/arm/include/asm/domain.h (revision 24168c5e6dfbdd5b414f048f47f75d64533296ca)
1 /* SPDX-License-Identifier: GPL-2.0-only */
2 /*
3  *  arch/arm/include/asm/domain.h
4  *
5  *  Copyright (C) 1999 Russell King.
6  */
7 #ifndef __ASM_PROC_DOMAIN_H
8 #define __ASM_PROC_DOMAIN_H
9 
10 #ifndef __ASSEMBLY__
11 #include <linux/thread_info.h>
12 #include <asm/barrier.h>
13 #endif
14 
15 /*
16  * Domain numbers
17  *
18  *  DOMAIN_IO     - domain 2 includes all IO only
19  *  DOMAIN_USER   - domain 1 includes all user memory only
20  *  DOMAIN_KERNEL - domain 0 includes all kernel memory only
21  *
22  * The domain numbering depends on whether we support 36 physical
23  * address for I/O or not.  Addresses above the 32 bit boundary can
24  * only be mapped using supersections and supersections can only
25  * be set for domain 0.  We could just default to DOMAIN_IO as zero,
26  * but there may be systems with supersection support and no 36-bit
27  * addressing.  In such cases, we want to map system memory with
28  * supersections to reduce TLB misses and footprint.
29  *
30  * 36-bit addressing and supersections are only available on
31  * CPUs based on ARMv6+ or the Intel XSC3 core.
32  */
33 #ifndef CONFIG_IO_36
34 #define DOMAIN_KERNEL	0
35 #define DOMAIN_USER	1
36 #define DOMAIN_IO	2
37 #else
38 #define DOMAIN_KERNEL	2
39 #define DOMAIN_USER	1
40 #define DOMAIN_IO	0
41 #endif
42 #define DOMAIN_VECTORS	3
43 
44 /*
45  * Domain types
46  */
47 #define DOMAIN_NOACCESS	0
48 #define DOMAIN_CLIENT	1
49 #ifdef CONFIG_CPU_USE_DOMAINS
50 #define DOMAIN_MANAGER	3
51 #else
52 #define DOMAIN_MANAGER	1
53 #endif
54 
55 #define domain_mask(dom)	((3) << (2 * (dom)))
56 #define domain_val(dom,type)	((type) << (2 * (dom)))
57 
58 #ifdef CONFIG_CPU_SW_DOMAIN_PAN
59 #define DACR_INIT \
60 	(domain_val(DOMAIN_USER, DOMAIN_NOACCESS) | \
61 	 domain_val(DOMAIN_KERNEL, DOMAIN_MANAGER) | \
62 	 domain_val(DOMAIN_IO, DOMAIN_CLIENT) | \
63 	 domain_val(DOMAIN_VECTORS, DOMAIN_CLIENT))
64 #else
65 #define DACR_INIT \
66 	(domain_val(DOMAIN_USER, DOMAIN_CLIENT) | \
67 	 domain_val(DOMAIN_KERNEL, DOMAIN_MANAGER) | \
68 	 domain_val(DOMAIN_IO, DOMAIN_CLIENT) | \
69 	 domain_val(DOMAIN_VECTORS, DOMAIN_CLIENT))
70 #endif
71 
72 #define __DACR_DEFAULT \
73 	domain_val(DOMAIN_KERNEL, DOMAIN_CLIENT) | \
74 	domain_val(DOMAIN_IO, DOMAIN_CLIENT) | \
75 	domain_val(DOMAIN_VECTORS, DOMAIN_CLIENT)
76 
77 #define DACR_UACCESS_DISABLE	\
78 	(__DACR_DEFAULT | domain_val(DOMAIN_USER, DOMAIN_NOACCESS))
79 #define DACR_UACCESS_ENABLE	\
80 	(__DACR_DEFAULT | domain_val(DOMAIN_USER, DOMAIN_CLIENT))
81 
82 #ifndef __ASSEMBLY__
83 
84 #ifdef CONFIG_CPU_CP15_MMU
85 static __always_inline unsigned int get_domain(void)
86 {
87 	unsigned int domain;
88 
89 	asm(
90 	"mrc	p15, 0, %0, c3, c0	@ get domain"
91 	 : "=r" (domain)
92 	 : "m" (current_thread_info()->cpu_domain));
93 
94 	return domain;
95 }
96 
97 static __always_inline void set_domain(unsigned int val)
98 {
99 	asm volatile(
100 	"mcr	p15, 0, %0, c3, c0	@ set domain"
101 	  : : "r" (val) : "memory");
102 	isb();
103 }
104 #else
105 static __always_inline unsigned int get_domain(void)
106 {
107 	return 0;
108 }
109 
110 static __always_inline void set_domain(unsigned int val)
111 {
112 }
113 #endif
114 
115 /*
116  * Generate the T (user) versions of the LDR/STR and related
117  * instructions (inline assembly)
118  */
119 #ifdef CONFIG_CPU_USE_DOMAINS
120 #define TUSER(instr)		TUSERCOND(instr, )
121 #define TUSERCOND(instr, cond)	#instr "t" #cond
122 #else
123 #define TUSER(instr)		TUSERCOND(instr, )
124 #define TUSERCOND(instr, cond)	#instr #cond
125 #endif
126 
127 #else /* __ASSEMBLY__ */
128 
129 /*
130  * Generate the T (user) versions of the LDR/STR and related
131  * instructions
132  */
133 #ifdef CONFIG_CPU_USE_DOMAINS
134 #define TUSER(instr)	instr ## t
135 #else
136 #define TUSER(instr)	instr
137 #endif
138 
139 #endif /* __ASSEMBLY__ */
140 
141 #endif /* !__ASM_PROC_DOMAIN_H */
142