linux_dsm_epyc7002/arch/riscv/include/asm/hwcap.h
Anup Patel 6bcff51539
RISC-V: Add bitmap reprensenting ISA features common across CPUs
This patch adds riscv_isa bitmap which represents Host ISA features
common across all Host CPUs. The riscv_isa is not same as elf_hwcap
because elf_hwcap will only have ISA features relevant for user-space
apps whereas riscv_isa will have ISA features relevant to both kernel
and user-space apps.

One of the use-case for riscv_isa bitmap is in KVM hypervisor where
we will use it to do following operations:

1. Check whether hypervisor extension is available
2. Find ISA features that need to be virtualized (e.g. floating
   point support, vector extension, etc.)

Signed-off-by: Anup Patel <anup.patel@wdc.com>
Signed-off-by: Atish Patra <atish.patra@wdc.com>
Reviewed-by: Alexander Graf <graf@amazon.com>
Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com>
2020-05-04 14:08:59 -07:00

50 lines
1.2 KiB
C

/* SPDX-License-Identifier: GPL-2.0-only */
/*
* Copied from arch/arm64/include/asm/hwcap.h
*
* Copyright (C) 2012 ARM Ltd.
* Copyright (C) 2017 SiFive
*/
#ifndef _ASM_RISCV_HWCAP_H
#define _ASM_RISCV_HWCAP_H
#include <linux/bits.h>
#include <uapi/asm/hwcap.h>
#ifndef __ASSEMBLY__
/*
* This yields a mask that user programs can use to figure out what
* instruction set this cpu supports.
*/
#define ELF_HWCAP (elf_hwcap)
enum {
CAP_HWCAP = 1,
};
extern unsigned long elf_hwcap;
#define RISCV_ISA_EXT_a ('a' - 'a')
#define RISCV_ISA_EXT_c ('c' - 'a')
#define RISCV_ISA_EXT_d ('d' - 'a')
#define RISCV_ISA_EXT_f ('f' - 'a')
#define RISCV_ISA_EXT_h ('h' - 'a')
#define RISCV_ISA_EXT_i ('i' - 'a')
#define RISCV_ISA_EXT_m ('m' - 'a')
#define RISCV_ISA_EXT_s ('s' - 'a')
#define RISCV_ISA_EXT_u ('u' - 'a')
#define RISCV_ISA_EXT_MAX 64
unsigned long riscv_isa_extension_base(const unsigned long *isa_bitmap);
#define riscv_isa_extension_mask(ext) BIT_MASK(RISCV_ISA_EXT_##ext)
bool __riscv_isa_extension_available(const unsigned long *isa_bitmap, int bit);
#define riscv_isa_extension_available(isa_bitmap, ext) \
__riscv_isa_extension_available(isa_bitmap, RISCV_ISA_EXT_##ext)
#endif
#endif /* _ASM_RISCV_HWCAP_H */