xref: /openbmc/linux/arch/riscv/include/asm/hwcap.h (revision dff03381)
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 <linux/bits.h>
12 #include <uapi/asm/hwcap.h>
13 
14 #ifndef __ASSEMBLY__
15 #include <linux/jump_label.h>
16 /*
17  * This yields a mask that user programs can use to figure out what
18  * instruction set this cpu supports.
19  */
20 #define ELF_HWCAP		(elf_hwcap)
21 
22 enum {
23 	CAP_HWCAP = 1,
24 };
25 
26 extern unsigned long elf_hwcap;
27 
28 #define RISCV_ISA_EXT_a		('a' - 'a')
29 #define RISCV_ISA_EXT_c		('c' - 'a')
30 #define RISCV_ISA_EXT_d		('d' - 'a')
31 #define RISCV_ISA_EXT_f		('f' - 'a')
32 #define RISCV_ISA_EXT_h		('h' - 'a')
33 #define RISCV_ISA_EXT_i		('i' - 'a')
34 #define RISCV_ISA_EXT_m		('m' - 'a')
35 #define RISCV_ISA_EXT_s		('s' - 'a')
36 #define RISCV_ISA_EXT_u		('u' - 'a')
37 
38 /*
39  * Increse this to higher value as kernel support more ISA extensions.
40  */
41 #define RISCV_ISA_EXT_MAX	64
42 #define RISCV_ISA_EXT_NAME_LEN_MAX 32
43 
44 /* The base ID for multi-letter ISA extensions */
45 #define RISCV_ISA_EXT_BASE 26
46 
47 /*
48  * This enum represent the logical ID for each multi-letter RISC-V ISA extension.
49  * The logical ID should start from RISCV_ISA_EXT_BASE and must not exceed
50  * RISCV_ISA_EXT_MAX. 0-25 range is reserved for single letter
51  * extensions while all the multi-letter extensions should define the next
52  * available logical extension id.
53  */
54 enum riscv_isa_ext_id {
55 	RISCV_ISA_EXT_SSCOFPMF = RISCV_ISA_EXT_BASE,
56 	RISCV_ISA_EXT_SVPBMT,
57 	RISCV_ISA_EXT_ID_MAX = RISCV_ISA_EXT_MAX,
58 };
59 
60 /*
61  * This enum represents the logical ID for each RISC-V ISA extension static
62  * keys. We can use static key to optimize code path if some ISA extensions
63  * are available.
64  */
65 enum riscv_isa_ext_key {
66 	RISCV_ISA_EXT_KEY_FPU,		/* For 'F' and 'D' */
67 	RISCV_ISA_EXT_KEY_MAX,
68 };
69 
70 struct riscv_isa_ext_data {
71 	/* Name of the extension displayed to userspace via /proc/cpuinfo */
72 	char uprop[RISCV_ISA_EXT_NAME_LEN_MAX];
73 	/* The logical ISA extension ID */
74 	unsigned int isa_ext_id;
75 };
76 
77 extern struct static_key_false riscv_isa_ext_keys[RISCV_ISA_EXT_KEY_MAX];
78 
79 static __always_inline int riscv_isa_ext2key(int num)
80 {
81 	switch (num) {
82 	case RISCV_ISA_EXT_f:
83 		return RISCV_ISA_EXT_KEY_FPU;
84 	case RISCV_ISA_EXT_d:
85 		return RISCV_ISA_EXT_KEY_FPU;
86 	default:
87 		return -EINVAL;
88 	}
89 }
90 
91 unsigned long riscv_isa_extension_base(const unsigned long *isa_bitmap);
92 
93 #define riscv_isa_extension_mask(ext) BIT_MASK(RISCV_ISA_EXT_##ext)
94 
95 bool __riscv_isa_extension_available(const unsigned long *isa_bitmap, int bit);
96 #define riscv_isa_extension_available(isa_bitmap, ext)	\
97 	__riscv_isa_extension_available(isa_bitmap, RISCV_ISA_EXT_##ext)
98 
99 #endif
100 
101 #endif /* _ASM_RISCV_HWCAP_H */
102