From 02d52fbd940af7d7fe0a523e99938113b2addd35 Mon Sep 17 00:00:00 2001 From: Atish Patra Date: Mon, 14 Mar 2022 13:38:43 -0700 Subject: RISC-V: Implement multi-letter ISA extension probing framework Multi-letter extensions can be probed using exising riscv_isa_extension_available API now. It doesn't support versioning right now as there is no use case for it. Individual extension specific implementation will be added during each extension support. Tested-by: Heiko Stuebner Signed-off-by: Atish Patra Reviewed-by: Anup Patel Signed-off-by: Palmer Dabbelt --- arch/riscv/include/asm/hwcap.h | 18 ++++++++++++++++++ 1 file changed, 18 insertions(+) (limited to 'arch/riscv/include') diff --git a/arch/riscv/include/asm/hwcap.h b/arch/riscv/include/asm/hwcap.h index 5ce50468aff1..170bd80da520 100644 --- a/arch/riscv/include/asm/hwcap.h +++ b/arch/riscv/include/asm/hwcap.h @@ -34,7 +34,25 @@ extern unsigned long elf_hwcap; #define RISCV_ISA_EXT_s ('s' - 'a') #define RISCV_ISA_EXT_u ('u' - 'a') +/* + * Increse this to higher value as kernel support more ISA extensions. + */ #define RISCV_ISA_EXT_MAX 64 +#define RISCV_ISA_EXT_NAME_LEN_MAX 32 + +/* The base ID for multi-letter ISA extensions */ +#define RISCV_ISA_EXT_BASE 26 + +/* + * This enum represent the logical ID for each multi-letter RISC-V ISA extension. + * The logical ID should start from RISCV_ISA_EXT_BASE and must not exceed + * RISCV_ISA_EXT_MAX. 0-25 range is reserved for single letter + * extensions while all the multi-letter extensions should define the next + * available logical extension id. + */ +enum riscv_isa_ext_id { + RISCV_ISA_EXT_ID_MAX = RISCV_ISA_EXT_MAX, +}; unsigned long riscv_isa_extension_base(const unsigned long *isa_bitmap); -- cgit