From 8963d6224009d7ac0523a05ceb9ea5d04ad5d12d Mon Sep 17 00:00:00 2001 From: Heiko Stuebner Date: Fri, 23 Dec 2022 23:13:29 +0100 Subject: [PATCH] RISC-V: add U-type imm parsing to insn.h header Similar to other existing types, allow extracting the immediate for a U-type instruction. U-type immediates are special in that regard, that the value in the instruction in bits [31:12] already represents the same bits of the immediate, so no shifting is required. U-type immediates are for example used in the auipc instruction, so these constants make it easier to parse such instructions. Reviewed-by: Conor Dooley Reviewed-by: Andrew Jones Reviewed-by: Lad Prabhakar Signed-off-by: Heiko Stuebner Link: https://lore.kernel.org/r/20221223221332.4127602-10-heiko@sntech.de Signed-off-by: Palmer Dabbelt --- arch/riscv/include/asm/insn.h | 13 +++++++++++++ 1 file changed, 13 insertions(+) diff --git a/arch/riscv/include/asm/insn.h b/arch/riscv/include/asm/insn.h index 50c899cf4de5..21ec817abec1 100644 --- a/arch/riscv/include/asm/insn.h +++ b/arch/riscv/include/asm/insn.h @@ -34,6 +34,15 @@ #define RV_J_IMM_11_MASK GENMASK(0, 0) #define RV_J_IMM_19_12_MASK GENMASK(7, 0) +/* + * U-type IMMs contain the upper 20bits [31:20] of an immediate with + * the rest filled in by zeros, so no shifting required. Similarly, + * bit31 contains the signed state, so no sign extension necessary. + */ +#define RV_U_IMM_SIGN_OPOFF 31 +#define RV_U_IMM_31_12_OPOFF 0 +#define RV_U_IMM_31_12_MASK GENMASK(31, 12) + /* The bit field of immediate value in B-type instruction */ #define RV_B_IMM_SIGN_OPOFF 31 #define RV_B_IMM_10_5_OPOFF 25 @@ -235,6 +244,10 @@ static __always_inline bool riscv_insn_is_branch(u32 code) #define RV_X(X, s, mask) (((X) >> (s)) & (mask)) #define RVC_X(X, s, mask) RV_X(X, s, mask) +#define RV_EXTRACT_UTYPE_IMM(x) \ + ({typeof(x) x_ = (x); \ + (RV_X(x_, RV_U_IMM_31_12_OPOFF, RV_U_IMM_31_12_MASK)); }) + #define RV_EXTRACT_JTYPE_IMM(x) \ ({typeof(x) x_ = (x); \ (RV_X(x_, RV_J_IMM_10_1_OPOFF, RV_J_IMM_10_1_MASK) << RV_J_IMM_10_1_OFF) | \ -- 2.20.1