arch/riscv/include/asm/cpufeature-macros.h

   1 /* SPDX-License-Identifier: GPL-2.0-only */
   2 /*
   3  * Copyright 2022-2024 Rivos, Inc
   4  */
   5
   6 #ifndef _ASM_CPUFEATURE_MACROS_H
   7 #define _ASM_CPUFEATURE_MACROS_H
   8
   9 #include <asm/hwcap.h>
  10 #include <asm/alternative-macros.h>
  11
  12 #define STANDARD_EXT            0
  13
  14 bool __riscv_isa_extension_available(const unsigned long *isa_bitmap, unsigned int bit);
  15 #define riscv_isa_extension_available(isa_bitmap, ext)  \
  16         __riscv_isa_extension_available(isa_bitmap, RISCV_ISA_EXT_##ext)
  17
  18 static __always_inline bool __riscv_has_extension_likely(const unsigned long vendor,
  19                                                          const unsigned long ext)
  20 {
  21         asm goto(ALTERNATIVE("j %l[l_no]", "nop", %[vendor], %[ext], 1)
  22         :
  23         : [vendor] "i" (vendor), [ext] "i" (ext)
  24         :
  25         : l_no);
  26
  27         return true;
  28 l_no:
  29         return false;
  30 }
  31
  32 static __always_inline bool __riscv_has_extension_unlikely(const unsigned long vendor,
  33                                                            const unsigned long ext)
  34 {
  35         asm goto(ALTERNATIVE("nop", "j  %l[l_yes]", %[vendor], %[ext], 1)
  36         :
  37         : [vendor] "i" (vendor), [ext] "i" (ext)
  38         :
  39         : l_yes);
  40
  41         return false;
  42 l_yes:
  43         return true;
  44 }
  45
  46 static __always_inline bool riscv_has_extension_unlikely(const unsigned long ext)
  47 {
  48         compiletime_assert(ext < RISCV_ISA_EXT_MAX, "ext must be < RISCV_ISA_EXT_MAX");
  49
  50         if (IS_ENABLED(CONFIG_RISCV_ALTERNATIVE))
  51                 return __riscv_has_extension_unlikely(STANDARD_EXT, ext);
  52
  53         return __riscv_isa_extension_available(NULL, ext);
  54 }
  55
  56 static __always_inline bool riscv_has_extension_likely(const unsigned long ext)
  57 {
  58         compiletime_assert(ext < RISCV_ISA_EXT_MAX, "ext must be < RISCV_ISA_EXT_MAX");
  59
  60         if (IS_ENABLED(CONFIG_RISCV_ALTERNATIVE))
  61                 return __riscv_has_extension_likely(STANDARD_EXT, ext);
  62
  63         return __riscv_isa_extension_available(NULL, ext);
  64 }
  65
  66 #endif /* _ASM_CPUFEATURE_MACROS_H */