diff options
Diffstat (limited to 'Documentation')
| -rw-r--r-- | Documentation/arch/riscv/hwprobe.rst | 36 |
1 files changed, 22 insertions, 14 deletions
diff --git a/Documentation/arch/riscv/hwprobe.rst b/Documentation/arch/riscv/hwprobe.rst index 3db60a0911df..85b709257918 100644 --- a/Documentation/arch/riscv/hwprobe.rst +++ b/Documentation/arch/riscv/hwprobe.rst @@ -239,25 +239,33 @@ The following keys are defined: ratified in commit 98918c844281 ("Merge pull request #1217 from riscv/zawrs") of riscv-isa-manual. -* :c:macro:`RISCV_HWPROBE_KEY_CPUPERF_0`: A bitmask that contains performance - information about the selected set of processors. +* :c:macro:`RISCV_HWPROBE_KEY_CPUPERF_0`: Deprecated. Returns similar values to + :c:macro:`RISCV_HWPROBE_KEY_MISALIGNED_SCALAR_PERF`, but the key was + mistakenly classified as a bitmask rather than a value. - * :c:macro:`RISCV_HWPROBE_MISALIGNED_UNKNOWN`: The performance of misaligned - accesses is unknown. +* :c:macro:`RISCV_HWPROBE_KEY_MISALIGNED_SCALAR_PERF`: An enum value describing + the performance of misaligned scalar native word accesses on the selected set + of processors. - * :c:macro:`RISCV_HWPROBE_MISALIGNED_EMULATED`: Misaligned accesses are - emulated via software, either in or below the kernel. These accesses are - always extremely slow. + * :c:macro:`RISCV_HWPROBE_MISALIGNED_SCALAR_UNKNOWN`: The performance of + misaligned scalar accesses is unknown. - * :c:macro:`RISCV_HWPROBE_MISALIGNED_SLOW`: Misaligned accesses are slower - than equivalent byte accesses. Misaligned accesses may be supported - directly in hardware, or trapped and emulated by software. + * :c:macro:`RISCV_HWPROBE_MISALIGNED_SCALAR_EMULATED`: Misaligned scalar + accesses are emulated via software, either in or below the kernel. These + accesses are always extremely slow. - * :c:macro:`RISCV_HWPROBE_MISALIGNED_FAST`: Misaligned accesses are faster - than equivalent byte accesses. + * :c:macro:`RISCV_HWPROBE_MISALIGNED_SCALAR_SLOW`: Misaligned scalar native + word sized accesses are slower than the equivalent quantity of byte + accesses. Misaligned accesses may be supported directly in hardware, or + trapped and emulated by software. - * :c:macro:`RISCV_HWPROBE_MISALIGNED_UNSUPPORTED`: Misaligned accesses are - not supported at all and will generate a misaligned address fault. + * :c:macro:`RISCV_HWPROBE_MISALIGNED_SCALAR_FAST`: Misaligned scalar native + word sized accesses are faster than the equivalent quantity of byte + accesses. + + * :c:macro:`RISCV_HWPROBE_MISALIGNED_SCALAR_UNSUPPORTED`: Misaligned scalar + accesses are not supported at all and will generate a misaligned address + fault. * :c:macro:`RISCV_HWPROBE_KEY_ZICBOZ_BLOCK_SIZE`: An unsigned int which represents the size of the Zicboz block in bytes. |