xref: /openbmc/linux/arch/riscv/include/asm/hwcap.h (revision 94eacb45)
1 /* SPDX-License-Identifier: GPL-2.0-only */
2 /*
3  * Copied from arch/arm64/include/asm/hwcap.h
4  *
5  * Copyright (C) 2012 ARM Ltd.
6  * Copyright (C) 2017 SiFive
7  */
8 #ifndef _ASM_RISCV_HWCAP_H
9 #define _ASM_RISCV_HWCAP_H
10 
11 #include <asm/alternative-macros.h>
12 #include <asm/errno.h>
13 #include <linux/bits.h>
14 #include <uapi/asm/hwcap.h>
15 
16 #define RISCV_ISA_EXT_a		('a' - 'a')
17 #define RISCV_ISA_EXT_b		('b' - 'a')
18 #define RISCV_ISA_EXT_c		('c' - 'a')
19 #define RISCV_ISA_EXT_d		('d' - 'a')
20 #define RISCV_ISA_EXT_f		('f' - 'a')
21 #define RISCV_ISA_EXT_h		('h' - 'a')
22 #define RISCV_ISA_EXT_i		('i' - 'a')
23 #define RISCV_ISA_EXT_j		('j' - 'a')
24 #define RISCV_ISA_EXT_k		('k' - 'a')
25 #define RISCV_ISA_EXT_m		('m' - 'a')
26 #define RISCV_ISA_EXT_p		('p' - 'a')
27 #define RISCV_ISA_EXT_q		('q' - 'a')
28 #define RISCV_ISA_EXT_s		('s' - 'a')
29 #define RISCV_ISA_EXT_u		('u' - 'a')
30 #define RISCV_ISA_EXT_v		('v' - 'a')
31 
32 /*
33  * These macros represent the logical IDs of each multi-letter RISC-V ISA
34  * extension and are used in the ISA bitmap. The logical IDs start from
35  * RISCV_ISA_EXT_BASE, which allows the 0-25 range to be reserved for single
36  * letter extensions. The maximum, RISCV_ISA_EXT_MAX, is defined in order
37  * to allocate the bitmap and may be increased when necessary.
38  *
39  * New extensions should just be added to the bottom, rather than added
40  * alphabetically, in order to avoid unnecessary shuffling.
41  */
42 #define RISCV_ISA_EXT_BASE		26
43 
44 #define RISCV_ISA_EXT_SSCOFPMF		26
45 #define RISCV_ISA_EXT_SSTC		27
46 #define RISCV_ISA_EXT_SVINVAL		28
47 #define RISCV_ISA_EXT_SVPBMT		29
48 #define RISCV_ISA_EXT_ZBB		30
49 #define RISCV_ISA_EXT_ZICBOM		31
50 #define RISCV_ISA_EXT_ZIHINTPAUSE	32
51 #define RISCV_ISA_EXT_SVNAPOT		33
52 #define RISCV_ISA_EXT_ZICBOZ		34
53 #define RISCV_ISA_EXT_SMAIA		35
54 #define RISCV_ISA_EXT_SSAIA		36
55 #define RISCV_ISA_EXT_ZBA		37
56 #define RISCV_ISA_EXT_ZBS		38
57 #define RISCV_ISA_EXT_ZICNTR		39
58 #define RISCV_ISA_EXT_ZICSR		40
59 #define RISCV_ISA_EXT_ZIFENCEI		41
60 #define RISCV_ISA_EXT_ZIHPM		42
61 
62 #define RISCV_ISA_EXT_MAX		64
63 
64 #ifdef CONFIG_RISCV_M_MODE
65 #define RISCV_ISA_EXT_SxAIA		RISCV_ISA_EXT_SMAIA
66 #else
67 #define RISCV_ISA_EXT_SxAIA		RISCV_ISA_EXT_SSAIA
68 #endif
69 
70 #ifndef __ASSEMBLY__
71 
72 #include <linux/jump_label.h>
73 
74 unsigned long riscv_get_elf_hwcap(void);
75 
76 struct riscv_isa_ext_data {
77 	const unsigned int id;
78 	const char *name;
79 	const char *property;
80 };
81 
82 extern const struct riscv_isa_ext_data riscv_isa_ext[];
83 extern const size_t riscv_isa_ext_count;
84 extern bool riscv_isa_fallback;
85 
86 unsigned long riscv_isa_extension_base(const unsigned long *isa_bitmap);
87 
88 #define riscv_isa_extension_mask(ext) BIT_MASK(RISCV_ISA_EXT_##ext)
89 
90 bool __riscv_isa_extension_available(const unsigned long *isa_bitmap, int bit);
91 #define riscv_isa_extension_available(isa_bitmap, ext)	\
92 	__riscv_isa_extension_available(isa_bitmap, RISCV_ISA_EXT_##ext)
93 
94 static __always_inline bool
95 riscv_has_extension_likely(const unsigned long ext)
96 {
97 	compiletime_assert(ext < RISCV_ISA_EXT_MAX,
98 			   "ext must be < RISCV_ISA_EXT_MAX");
99 
100 	if (IS_ENABLED(CONFIG_RISCV_ALTERNATIVE)) {
101 		asm_volatile_goto(
102 		ALTERNATIVE("j	%l[l_no]", "nop", 0, %[ext], 1)
103 		:
104 		: [ext] "i" (ext)
105 		:
106 		: l_no);
107 	} else {
108 		if (!__riscv_isa_extension_available(NULL, ext))
109 			goto l_no;
110 	}
111 
112 	return true;
113 l_no:
114 	return false;
115 }
116 
117 static __always_inline bool
118 riscv_has_extension_unlikely(const unsigned long ext)
119 {
120 	compiletime_assert(ext < RISCV_ISA_EXT_MAX,
121 			   "ext must be < RISCV_ISA_EXT_MAX");
122 
123 	if (IS_ENABLED(CONFIG_RISCV_ALTERNATIVE)) {
124 		asm_volatile_goto(
125 		ALTERNATIVE("nop", "j	%l[l_yes]", 0, %[ext], 1)
126 		:
127 		: [ext] "i" (ext)
128 		:
129 		: l_yes);
130 	} else {
131 		if (__riscv_isa_extension_available(NULL, ext))
132 			goto l_yes;
133 	}
134 
135 	return false;
136 l_yes:
137 	return true;
138 }
139 
140 #endif
141 
142 #endif /* _ASM_RISCV_HWCAP_H */
143