diff options
| author | Evan Green <evan@rivosinc.com> | 2023-04-08 02:10:59 +0300 |
|---|---|---|
| committer | Palmer Dabbelt <palmer@rivosinc.com> | 2023-04-19 01:48:14 +0300 |
| commit | ea3de9ce8aa280c5175c835bd3e94a3a9b814b74 (patch) | |
| tree | 835575d48af67ab432d8e3497d9156538f8e6668 /arch/riscv/include/uapi | |
| parent | ff77cf5b2e033d0bb5e3b7f83ebf65c5adc20d12 (diff) | |
| download | linux-ea3de9ce8aa280c5175c835bd3e94a3a9b814b74.tar.xz | |
RISC-V: Add a syscall for HW probing
We don't have enough space for these all in ELF_HWCAP{,2} and there's no
system call that quite does this, so let's just provide an arch-specific
one to probe for hardware capabilities. This currently just provides
m{arch,imp,vendor}id, but with the key-value pairs we can pass more in
the future.
Co-developed-by: Palmer Dabbelt <palmer@rivosinc.com>
Signed-off-by: Evan Green <evan@rivosinc.com>
Reviewed-by: Conor Dooley <conor.dooley@microchip.com>
Reviewed-by: Heiko Stuebner <heiko.stuebner@vrull.eu>
Tested-by: Heiko Stuebner <heiko.stuebner@vrull.eu>
Reviewed-by: Paul Walmsley <paul.walmsley@sifive.com>
Link: https://lore.kernel.org/r/20230407231103.2622178-3-evan@rivosinc.com
Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
Diffstat (limited to 'arch/riscv/include/uapi')
| -rw-r--r-- | arch/riscv/include/uapi/asm/hwprobe.h | 25 | ||||
| -rw-r--r-- | arch/riscv/include/uapi/asm/unistd.h | 9 |
2 files changed, 34 insertions, 0 deletions
diff --git a/arch/riscv/include/uapi/asm/hwprobe.h b/arch/riscv/include/uapi/asm/hwprobe.h new file mode 100644 index 000000000000..b79be00920db --- /dev/null +++ b/arch/riscv/include/uapi/asm/hwprobe.h @@ -0,0 +1,25 @@ +/* SPDX-License-Identifier: GPL-2.0 WITH Linux-syscall-note */ +/* + * Copyright 2023 Rivos, Inc + */ + +#ifndef _UAPI_ASM_HWPROBE_H +#define _UAPI_ASM_HWPROBE_H + +#include <linux/types.h> + +/* + * Interface for probing hardware capabilities from userspace, see + * Documentation/riscv/hwprobe.rst for more information. + */ +struct riscv_hwprobe { + __s64 key; + __u64 value; +}; + +#define RISCV_HWPROBE_KEY_MVENDORID 0 +#define RISCV_HWPROBE_KEY_MARCHID 1 +#define RISCV_HWPROBE_KEY_MIMPID 2 +/* Increase RISCV_HWPROBE_MAX_KEY when adding items. */ + +#endif diff --git a/arch/riscv/include/uapi/asm/unistd.h b/arch/riscv/include/uapi/asm/unistd.h index 73d7cdd2ec49..950ab3fd4409 100644 --- a/arch/riscv/include/uapi/asm/unistd.h +++ b/arch/riscv/include/uapi/asm/unistd.h @@ -43,3 +43,12 @@ #define __NR_riscv_flush_icache (__NR_arch_specific_syscall + 15) #endif __SYSCALL(__NR_riscv_flush_icache, sys_riscv_flush_icache) + +/* + * Allows userspace to query the kernel for CPU architecture and + * microarchitecture details across a given set of CPUs. + */ +#ifndef __NR_riscv_hwprobe +#define __NR_riscv_hwprobe (__NR_arch_specific_syscall + 14) +#endif +__SYSCALL(__NR_riscv_hwprobe, sys_riscv_hwprobe) |