xref: /openbmc/linux/arch/riscv/include/asm/hwcap.h (revision 2a598d0b)
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 #define RISCV_ISA_EXT_v		('v' - 'a')
26 
27 /*
28  * These macros represent the logical IDs of each multi-letter RISC-V ISA
29  * extension and are used in the ISA bitmap. The logical IDs start from
30  * RISCV_ISA_EXT_BASE, which allows the 0-25 range to be reserved for single
31  * letter extensions. The maximum, RISCV_ISA_EXT_MAX, is defined in order
32  * to allocate the bitmap and may be increased when necessary.
33  *
34  * New extensions should just be added to the bottom, rather than added
35  * alphabetically, in order to avoid unnecessary shuffling.
36  */
37 #define RISCV_ISA_EXT_BASE		26
38 
39 #define RISCV_ISA_EXT_SSCOFPMF		26
40 #define RISCV_ISA_EXT_SSTC		27
41 #define RISCV_ISA_EXT_SVINVAL		28
42 #define RISCV_ISA_EXT_SVPBMT		29
43 #define RISCV_ISA_EXT_ZBB		30
44 #define RISCV_ISA_EXT_ZICBOM		31
45 #define RISCV_ISA_EXT_ZIHINTPAUSE	32
46 #define RISCV_ISA_EXT_SVNAPOT		33
47 #define RISCV_ISA_EXT_ZICBOZ		34
48 #define RISCV_ISA_EXT_SMAIA		35
49 #define RISCV_ISA_EXT_SSAIA		36
50 #define RISCV_ISA_EXT_ZBA		37
51 #define RISCV_ISA_EXT_ZBS		38
52 #define RISCV_ISA_EXT_ZICNTR		39
53 #define RISCV_ISA_EXT_ZICSR		40
54 #define RISCV_ISA_EXT_ZIFENCEI		41
55 #define RISCV_ISA_EXT_ZIHPM		42
56 
57 #define RISCV_ISA_EXT_MAX		64
58 #define RISCV_ISA_EXT_NAME_LEN_MAX	32
59 
60 #ifdef CONFIG_RISCV_M_MODE
61 #define RISCV_ISA_EXT_SxAIA		RISCV_ISA_EXT_SMAIA
62 #else
63 #define RISCV_ISA_EXT_SxAIA		RISCV_ISA_EXT_SSAIA
64 #endif
65 
66 #ifndef __ASSEMBLY__
67 
68 #include <linux/jump_label.h>
69 
70 unsigned long riscv_get_elf_hwcap(void);
71 
72 struct riscv_isa_ext_data {
73 	/* Name of the extension displayed to userspace via /proc/cpuinfo */
74 	char uprop[RISCV_ISA_EXT_NAME_LEN_MAX];
75 	/* The logical ISA extension ID */
76 	unsigned int isa_ext_id;
77 };
78 
79 unsigned long riscv_isa_extension_base(const unsigned long *isa_bitmap);
80 
81 #define riscv_isa_extension_mask(ext) BIT_MASK(RISCV_ISA_EXT_##ext)
82 
83 bool __riscv_isa_extension_available(const unsigned long *isa_bitmap, int bit);
84 #define riscv_isa_extension_available(isa_bitmap, ext)	\
85 	__riscv_isa_extension_available(isa_bitmap, RISCV_ISA_EXT_##ext)
86 
87 static __always_inline bool
88 riscv_has_extension_likely(const unsigned long ext)
89 {
90 	compiletime_assert(ext < RISCV_ISA_EXT_MAX,
91 			   "ext must be < RISCV_ISA_EXT_MAX");
92 
93 	if (IS_ENABLED(CONFIG_RISCV_ALTERNATIVE)) {
94 		asm_volatile_goto(
95 		ALTERNATIVE("j	%l[l_no]", "nop", 0, %[ext], 1)
96 		:
97 		: [ext] "i" (ext)
98 		:
99 		: l_no);
100 	} else {
101 		if (!__riscv_isa_extension_available(NULL, ext))
102 			goto l_no;
103 	}
104 
105 	return true;
106 l_no:
107 	return false;
108 }
109 
110 static __always_inline bool
111 riscv_has_extension_unlikely(const unsigned long ext)
112 {
113 	compiletime_assert(ext < RISCV_ISA_EXT_MAX,
114 			   "ext must be < RISCV_ISA_EXT_MAX");
115 
116 	if (IS_ENABLED(CONFIG_RISCV_ALTERNATIVE)) {
117 		asm_volatile_goto(
118 		ALTERNATIVE("nop", "j	%l[l_yes]", 0, %[ext], 1)
119 		:
120 		: [ext] "i" (ext)
121 		:
122 		: l_yes);
123 	} else {
124 		if (__riscv_isa_extension_available(NULL, ext))
125 			goto l_yes;
126 	}
127 
128 	return false;
129 l_yes:
130 	return true;
131 }
132 
133 #endif
134 
135 #endif /* _ASM_RISCV_HWCAP_H */
136