xref: /linux/arch/riscv/include/asm/hwcap.h (revision ff19a8dee196d757dbc32a946843260f0b784ca3)
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_c		('c' - 'a')
18 #define RISCV_ISA_EXT_d		('d' - 'a')
19 #define RISCV_ISA_EXT_f		('f' - 'a')
20 #define RISCV_ISA_EXT_h		('h' - 'a')
21 #define RISCV_ISA_EXT_i		('i' - 'a')
22 #define RISCV_ISA_EXT_m		('m' - 'a')
23 #define RISCV_ISA_EXT_s		('s' - 'a')
24 #define RISCV_ISA_EXT_u		('u' - 'a')
25 
26 /*
27  * These macros represent the logical IDs of each multi-letter RISC-V ISA
28  * extension and are used in the ISA bitmap. The logical IDs start from
29  * RISCV_ISA_EXT_BASE, which allows the 0-25 range to be reserved for single
30  * letter extensions. The maximum, RISCV_ISA_EXT_MAX, is defined in order
31  * to allocate the bitmap and may be increased when necessary.
32  *
33  * New extensions should just be added to the bottom, rather than added
34  * alphabetically, in order to avoid unnecessary shuffling.
35  */
36 #define RISCV_ISA_EXT_BASE		26
37 
38 #define RISCV_ISA_EXT_SSCOFPMF		26
39 #define RISCV_ISA_EXT_SSTC		27
40 #define RISCV_ISA_EXT_SVINVAL		28
41 #define RISCV_ISA_EXT_SVPBMT		29
42 #define RISCV_ISA_EXT_ZBB		30
43 #define RISCV_ISA_EXT_ZICBOM		31
44 #define RISCV_ISA_EXT_ZIHINTPAUSE	32
45 
46 #define RISCV_ISA_EXT_MAX		64
47 #define RISCV_ISA_EXT_NAME_LEN_MAX	32
48 
49 #ifndef __ASSEMBLY__
50 
51 #include <linux/jump_label.h>
52 
53 struct riscv_isa_ext_data {
54 	/* Name of the extension displayed to userspace via /proc/cpuinfo */
55 	char uprop[RISCV_ISA_EXT_NAME_LEN_MAX];
56 	/* The logical ISA extension ID */
57 	unsigned int isa_ext_id;
58 };
59 
60 static __always_inline bool
61 riscv_has_extension_likely(const unsigned long ext)
62 {
63 	compiletime_assert(ext < RISCV_ISA_EXT_MAX,
64 			   "ext must be < RISCV_ISA_EXT_MAX");
65 
66 	asm_volatile_goto(
67 	ALTERNATIVE("j	%l[l_no]", "nop", 0, %[ext], 1)
68 	:
69 	: [ext] "i" (ext)
70 	:
71 	: l_no);
72 
73 	return true;
74 l_no:
75 	return false;
76 }
77 
78 static __always_inline bool
79 riscv_has_extension_unlikely(const unsigned long ext)
80 {
81 	compiletime_assert(ext < RISCV_ISA_EXT_MAX,
82 			   "ext must be < RISCV_ISA_EXT_MAX");
83 
84 	asm_volatile_goto(
85 	ALTERNATIVE("nop", "j	%l[l_yes]", 0, %[ext], 1)
86 	:
87 	: [ext] "i" (ext)
88 	:
89 	: l_yes);
90 
91 	return false;
92 l_yes:
93 	return true;
94 }
95 
96 unsigned long riscv_isa_extension_base(const unsigned long *isa_bitmap);
97 
98 #define riscv_isa_extension_mask(ext) BIT_MASK(RISCV_ISA_EXT_##ext)
99 
100 bool __riscv_isa_extension_available(const unsigned long *isa_bitmap, int bit);
101 #define riscv_isa_extension_available(isa_bitmap, ext)	\
102 	__riscv_isa_extension_available(isa_bitmap, RISCV_ISA_EXT_##ext)
103 
104 #endif
105 
106 #endif /* _ASM_RISCV_HWCAP_H */
107