Unverified Commit 2e6f6ea4 authored by Samuel Holland's avatar Samuel Holland Committed by Palmer Dabbelt
Browse files

riscv: Add ISA extension parsing for pointer masking 



The RISC-V Pointer Masking specification defines three extensions:
Smmpm, Smnpm, and Ssnpm. Add support for parsing each of them. The
specific extension which provides pointer masking support to userspace
(Supm) depends on the kernel's privilege mode, so provide a macro to
abstract this selection.

Smmpm implies the existence of the mseccfg CSR. As it is the only user
of this CSR so far, there is no need for an Xlinuxmseccfg extension.

Reviewed-by: default avatarCharlie Jenkins <charlie@rivosinc.com>
Signed-off-by: default avatarSamuel Holland <samuel.holland@sifive.com>
Link: https://lore.kernel.org/r/20241016202814.4061541-3-samuel.holland@sifive.com


Signed-off-by: default avatarPalmer Dabbelt <palmer@rivosinc.com>
parent 8727163a

arch/riscv/include/asm/hwcap.h

+5 −0
Original line number Diff line number Diff line
@@ -93,6 +93,9 @@ 
#define RISCV_ISA_EXT_ZCMOP		84

#define RISCV_ISA_EXT_ZAWRS		85

#define RISCV_ISA_EXT_SVVPTC		86

#define RISCV_ISA_EXT_SMMPM		87

#define RISCV_ISA_EXT_SMNPM		88

#define RISCV_ISA_EXT_SSNPM		89



#define RISCV_ISA_EXT_XLINUXENVCFG	127
@@ -101,8 +104,10 @@ 


#ifdef CONFIG_RISCV_M_MODE

#define RISCV_ISA_EXT_SxAIA		RISCV_ISA_EXT_SMAIA

#define RISCV_ISA_EXT_SUPM		RISCV_ISA_EXT_SMNPM

#else

#define RISCV_ISA_EXT_SxAIA		RISCV_ISA_EXT_SSAIA

#define RISCV_ISA_EXT_SUPM		RISCV_ISA_EXT_SSNPM

#endif



#endif /* _ASM_RISCV_HWCAP_H */

arch/riscv/kernel/cpufeature.c

+3 −0
Original line number Diff line number Diff line
@@ -377,9 +377,12 @@ const struct riscv_isa_ext_data riscv_isa_ext[] = { 
	__RISCV_ISA_EXT_BUNDLE(zvksg, riscv_zvksg_bundled_exts),

	__RISCV_ISA_EXT_DATA(zvkt, RISCV_ISA_EXT_ZVKT),

	__RISCV_ISA_EXT_DATA(smaia, RISCV_ISA_EXT_SMAIA),

	__RISCV_ISA_EXT_DATA(smmpm, RISCV_ISA_EXT_SMMPM),

	__RISCV_ISA_EXT_SUPERSET(smnpm, RISCV_ISA_EXT_SMNPM, riscv_xlinuxenvcfg_exts),

	__RISCV_ISA_EXT_DATA(smstateen, RISCV_ISA_EXT_SMSTATEEN),

	__RISCV_ISA_EXT_DATA(ssaia, RISCV_ISA_EXT_SSAIA),

	__RISCV_ISA_EXT_DATA(sscofpmf, RISCV_ISA_EXT_SSCOFPMF),

	__RISCV_ISA_EXT_SUPERSET(ssnpm, RISCV_ISA_EXT_SSNPM, riscv_xlinuxenvcfg_exts),

	__RISCV_ISA_EXT_DATA(sstc, RISCV_ISA_EXT_SSTC),

	__RISCV_ISA_EXT_DATA(svinval, RISCV_ISA_EXT_SVINVAL),

	__RISCV_ISA_EXT_DATA(svnapot, RISCV_ISA_EXT_SVNAPOT),