[PATCH v16 04/27] riscv: zicfiss / zicfilp extension csr and bit definitions
From: Deepak Gupta <hidden>
Date: 2025-05-23 05:31:26
Also in:
linux-arch, linux-doc, linux-fsdevel, linux-kselftest, linux-mm, linux-riscv, lkml, rust-for-linux
Subsystem:
risc-v architecture, the rest · Maintainers:
Paul Walmsley, Palmer Dabbelt, Albert Ou, Linus Torvalds
zicfiss and zicfilp extension gets enabled via b3 and b2 in *envcfg CSR. menvcfg controls enabling for S/HS mode. henvcfg control enabling for VS while senvcfg controls enabling for U/VU mode. zicfilp extension extends *status CSR to hold `expected landing pad` bit. A trap or interrupt can occur between an indirect jmp/call and target instr. `expected landing pad` bit from CPU is recorded into xstatus CSR so that when supervisor performs xret, `expected landing pad` state of CPU can be restored. zicfiss adds one new CSR - CSR_SSP: CSR_SSP contains current shadow stack pointer. Signed-off-by: Deepak Gupta <redacted> Reviewed-by: Charlie Jenkins <redacted> --- arch/riscv/include/asm/csr.h | 16 ++++++++++++++++ 1 file changed, 16 insertions(+)
diff --git a/arch/riscv/include/asm/csr.h b/arch/riscv/include/asm/csr.h
index 6fed42e37705..2f49b9663640 100644
--- a/arch/riscv/include/asm/csr.h
+++ b/arch/riscv/include/asm/csr.h@@ -18,6 +18,15 @@ #define SR_MPP _AC(0x00001800, UL) /* Previously Machine */ #define SR_SUM _AC(0x00040000, UL) /* Supervisor User Memory Access */ +/* zicfilp landing pad status bit */ +#define SR_SPELP _AC(0x00800000, UL) +#define SR_MPELP _AC(0x020000000000, UL) +#ifdef CONFIG_RISCV_M_MODE +#define SR_ELP SR_MPELP +#else +#define SR_ELP SR_SPELP +#endif + #define SR_FS _AC(0x00006000, UL) /* Floating-point Status */ #define SR_FS_OFF _AC(0x00000000, UL) #define SR_FS_INITIAL _AC(0x00002000, UL)
@@ -212,6 +221,8 @@ #define ENVCFG_PMM_PMLEN_16 (_AC(0x3, ULL) << 32) #define ENVCFG_CBZE (_AC(1, UL) << 7) #define ENVCFG_CBCFE (_AC(1, UL) << 6) +#define ENVCFG_LPE (_AC(1, UL) << 2) +#define ENVCFG_SSE (_AC(1, UL) << 3) #define ENVCFG_CBIE_SHIFT 4 #define ENVCFG_CBIE (_AC(0x3, UL) << ENVCFG_CBIE_SHIFT) #define ENVCFG_CBIE_ILL _AC(0x0, UL)
@@ -230,6 +241,11 @@ #define SMSTATEEN0_HSENVCFG (_ULL(1) << SMSTATEEN0_HSENVCFG_SHIFT) #define SMSTATEEN0_SSTATEEN0_SHIFT 63 #define SMSTATEEN0_SSTATEEN0 (_ULL(1) << SMSTATEEN0_SSTATEEN0_SHIFT) +/* + * zicfiss user mode csr + * CSR_SSP holds current shadow stack pointer. + */ +#define CSR_SSP 0x011 /* mseccfg bits */ #define MSECCFG_PMM ENVCFG_PMM
--
2.43.0